Manual of

Ocular Pathology
 Manual of
Ocular Pathology
Jyotirmay Biswas MS, SNAMS
Director of Uveitis and Head
The Larsen and Toubro Ocular Pathology Department
Medical and Vision Research Foundation
Sankara Nethralaya, 18, College Road
Chennai 600 006, India
E-mail: drjb@snmail.org

S Krishnakumar MD
Larsen and Toubro Ocular Pathology
Medical and Vision Research Foundations
Sankara Nethralaya, 18, College Road
Chennai 600 006, India
E-mail: histopath@snmail.org

Shweta Ahuja MD
Larsen and Toubro Ocular Pathology
Medical and Vision Research Foundations
Sankara Nethralaya, 18 College Road
Chennai 600 006, India
E-mail: histopath@snmail.org

Foreword
Narsing A Rao
Published by
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Manual of Ocular Pathology

© 2010, Jaypee Brothers Medical Publishers (P) Ltd.

All rights reserved. No part of this publication should be reproduced, stored in a retrieval system,
or transmitted in any form or by any means: electronic, mechanical, photocopying, recording, or
otherwise, without the prior written permission of the authors and the publisher.

This book has been published in good faith that the material provided by authors is original.
Every effort is made to ensure accuracy of material, but the publisher, printer and authors will
not be held responsible for any inadvertent error (s). In case of any dispute, all legal matters
are to be settled under Delhi jurisdiction only.

First Edition: 2010

ISBN 978-81-8448-912-5

Typeset at JPBMP typesetting unit

Printed at Ajanta Offset

 I dedicate this book
to
my wife
Dr Shubhra Biswas and
my daughter
Ms Sumedha Biswas
–Jyotirmay Biswas
 FOREWORD

Biomicroscopy approach to clinical diagnosis of

ophthalmic diseases requires a sound knowledge in
histopathologic changes of ocular disorders. Unlike
many other disciplines in medicine, ophthalmic tissue
diagnosis creates a challenge due to tiny samples, which
are submitted for diagnosis thus requiring special skills
in offering proper diagnosis. Practical expertise of
Drs Biswas and Krishnakumar in the field of diagnostic
ophthalmic pathology, clinical ophthalmology and
general pathology offered a unique approach for them to undertake this book
in providing salient histopathologic diagnostic features and clinicopathologic
correlations.
The Manual of Ocular Pathology covers both the common and rare diseases
affecting the eye and ocular adnexa. Chapters are devoted to describe clinical
features followed by description of histopathologic changes of the lesions
occurring in eyelid, conjunctiva, cornea, lens, uvea, retina, and orbital tissue.
Moreover, this book provides outstanding illustrations on normal histology,
special stains and immunohistochemical findings including a brief outline
on prognosis. Interestingly, the authors have included general principles used
in sectioning of ophthalmic specimens based on anatomy, clinical findings
and macroscopic pathologic changes. Furthermore, the authors added a
chapter on ophthalmic changes seen in Acquired Immune Deficiency
Syndrome (AIDS).
The Manual of Ocular Pathology should prove useful to residents in
ophthalmology and pathology as well as to ophthalmic surgeons, clinicians,
pathologists and oncologists interested in diagnosis and management of ocular
diseases and neoplasia.

Narsing A Rao MD
Professor, Department of Ophthalmology and Pathology
Director of the A Ray Irvine, Jr., MD, Ophthalmic Pathology Laboratory
Doheny Eye Institute, University of Southern California
Los Angeles, California, USA
 PREFACE

I joined Sankara Nethralaya as a vitreoretinal fellow in

1984 when Dr Badrinath gave me a project to study the
cytopathology of vitreous fluids in various vitreoretinal
diseases. I realized that ophthalmic pathology is a
subspecialty that sets itself apart from general pathology
and needed to be addressed separately. So I decided to
dedicate my work to ocular pathology henceforth. In the
process, I was very fortunate to undergo training by
Dr Narsing Rao who taught me not only pathology but emphasized the
clinicopathologic correlation of eye diseases. It has been a 20-year journey
so far since 1989 and I have seen and documented a vast number of cases
due to the referral nature of my practice and the popularity of this institute.
I herewith would like to express my gratitude to my two mentors
Dr SS Badrinath and Dr Narsing Rao, without whose support and
encouragement I would not have become an ocular pathologist.
My thanks also go to Dr Lingam Gopal, Chairman of Sankara Nethralaya,
for his encouragement in writing this book.
I thank my colleague Dr S Krishnakumar who has joined me in 1998 and
has been ably supporting me.
I thank Dr Meghana Varde and Dr Anjali Manavalan for meticulously going
through the manuscript and editing it, giving suggestions and making
corrections.
I am very grateful to Dr Deepak Edward, ophthalmic pathologist and close
friend, for his constructive criticism and support.
I would like to thank Dr Dipankar Das my ex-fellow in ophthalmic
pathology and uveitis for going through the manuscript and helping me to
edit the book.
I would like to thank Mrs Vaijayanthi Pushparaj for rendering her help
in formatting this book and also for her excellent technical support.
I would also like to thank Ms Vanitha for performing good histopathological
preparations.
I thank Ms Abhirami R for writing on “Novel prognostic parameters in
uveal melanoma”.
This book is not a complete treatise but is intended to be a quick reference
guide to ophthalmic pathology for ophthalmologists as well as general
pathologists.

Jyotirmay Biswas
 CONTENTS

PART I

1. Introduction ............................................................................................... 1
2. Pathology of the Eyelid ........................................................................ 13
3. Pathology of the Conjunctiva .............................................................. 25
4. Pathology of the Cornea ....................................................................... 35
5. Pathology of the Lens ........................................................................... 45
6. Pathology of the Uvea ........................................................................... 51
7. Intraocular Tumors ................................................................................. 55

PART II

8. Diseases of the Retina .......................................................................... 69

9. Coats’ Disease ......................................................................................... 75
10. Diseases of the Vitreous ....................................................................... 77
11. Pathology of the Orbit .......................................................................... 81

PART III

12. Cytopathology of the Eye ..................................................................... 95

13. Frozen Section ....................................................................................... 109
14. Ocular Pathology in AIDS ................................................................. 113
15. Telepathology ........................................................................................ 117
References .................................................................................................. 119
Index ......................................................................................................... 129
2 MANUAL OF OCULAR PATHOLOGY

The eye is a unique organ with different histological structures incorporated

in it. This relatively small organ is affected by multitudes of diseases either
alone or as a part of a multisystem disorder. Ophthalmic pathology emerges
as a distinct subspecialty, both in ophthalmology and general pathology,
providing insight into changes occurring in the eye as a response to various
disease processes.
This book of ophthalmic pathology provides a brief review of the study
of ocular tissue and fluid specimens with clinicopathological correlation of
common ocular lesions.
Sir William Osler, Canadian-born famous physician of his time wrote: “As
is our pathology, so is our practice”. This phrase underlines the importance
of the subject in understanding diseases.
Ophthalmic pathology as a subspecialty is a relatively new field. General
pathologists are not usually exposed to ophthalmic slides and ophthalmo-
logists are not commonly exposed to pathology laboratories and specimens.
In India, there are only few ophthalmic pathology laboratories, so that this
brief introduction to ophthalmic pathology will be of great interest and use
to general pathologists as well as clinical ophthalmologists.
Histopathology of the eye includes the pathology of the skin of various
structures of the eye itself, central nervous system pathology as well as a large
number of benign and malignant tumors. The eye can be affected in various
systemic disorders, some of them presenting primarily with ocular symptoms.
Thorough understanding of the eye’s normal structures and pathologic
changes can be important for the diagnosis of potentially serious sight or even
life-threatening diseases. Recent advances, including immunohistochemistry,
chromosome in situ hybridization, real time PCR, proteomics, microarray as
well as micro RNA and electron microscopy add to the numerous aspects
of ocular histopathology. This book gives an overview of the basic concepts
and practices in ocular histopathology, introduces normal histology of the
eye and provides clinicopathological correlations of selected common ocular
lesions often subjected to histopathological analysis in practice.
Part I deals with the descriptions of pathology specimens, fixation, grossing
and sectioning of the globe in a systemic way to help the reader understand
the basic techniques required in ophthalmic pathology. Part II deals with the
most commonly encountered diseases affecting the eye and its adnexa, divided
into pathology of the lid, conjunctiva, cornea, lens, uvea, retina and orbit.
The last part introduces topics such as cytopathology of the eye, AIDS-
associated ocular diseases, frozen section and telepathology. A list of Sankara
Nethralaya publications on ophthalmic pathology and selected references are
included at the end for further reading.
We hope this book will be a great resource for resident trainees in
ophthalmology and pathology, fellows, practicing ophthalmologists, general
pathologists, ophthalmic pathologists and oncologists.
 INTRODUCTION 3
OPHTHALMIC PATHOLOGY SPECIMENS
Types of specimens received in the ophthalmic pathology laboratory are:
1. Eyeballs –removed following enucleation, as part of exenteration specimen
or autopsy.
2. Portion of the eye removed during various surgical procedures, e.g.:
a. Corneal button – following keratoplasty
b. Lens – following cataract surgery
c. Trabeculectomy specimen – following glaucoma surgery
d. Vitreous Specimen following vitrectomy
e. Epiretinal membrane, retinal or retinochoroidal tissue—following retinal
surgery or biopsy for specific conditions
3. Biopsy – from:
a. Lid
b. Conjunctiva
c. Cornea
d. Iris
e. Orbit
f. Retina, choroid or retinochoroidal tissue
g. Any ocular tissue
4. Aspiration material from anterior chamber or vitreous cavity or any cystic
lesion of the eye and orbit.
5. Scraping from superficial structures, e.g. conjunctiva or cornea.

PATHOLOGIC STUDY
Some aspects of pathologic study of ophthalmic specimens are different from
other branches of pathology and are highlighted here.

Processing of Biopsy Specimen

Ophthalmic biopsy specimens are often quite small and require utmost care
in handling and processing. Before processing, the pathologist should review
the patient clinical history with relevant ophthalmic findings and diagnosis.

Processing of Tissues Includes

Fixation
Proper fixation of biopsy tissue is a crucial step in tissue processing. A volume
of fixative about 10-15 times the volume of the biopsy specimen will ensure
proper fixation.
1. Time required for fixation is as follows:
• Corneal button — 6 hours
• Globe or large orbital mass — 24 hours
• Exenteration specimen — 72 hours
4 MANUAL OF OCULAR PATHOLOGY

Various fixatives used are:

a. Routine histopathology
10% Neutral buffered formalin.
b. Cytology studies — 95% ethanol.
c. Electron microscopy— 2-2.5% glutaraldehyde.
d. Flow cytometry— Tissue culture medium.

GROSS EXAMINATION OF THE SPECIMENS

Eyeball Specimens
Steps
a. Identification of the side
b. Measurement
c. Gross inspection
d. Transillumination
e. Sectioning of the globe
f. Internal description.
g. Tumor sample collection for molecular biology studies

a. Identification of the Side of the Globe

The following topographical landmarks are helpful in identification of the
side of the globe:
i. Horizontal meridian: Posterior ciliary vessels emerge from the lateral and
medial aspects of the optic nerve horizontally. These are present as blue
lines on either side of the optic nerve, more prominent on the nasal side.
Posterior ciliary vessels are obliterated on the temporal side due to the
insertion of the inferior oblique muscle (Figure 1.1).
 INTRODUCTION 5

Figure 1.1: Gross photograph of the posterior surface of globe showing posterior ciliary
vein by the side of the optic nerve (arrow)

ii. Vertical meridian: It is determined by the insertion of the inferior oblique

muscle which is on the temporal side of the optic nerve. There are few
more additional points which can be taken into consideration in
identifying the side of the globe
iii. Temporal curve, i.e. distance between limbus and optic nerve edge on
the temporal side is more than its counterpart on the nasal side.
iv. The cornea is normally horizontally oval, i.e. the horizontal diameter is more
than the vertical diameter. It helps in determining the horizontal meridian.

b. Measurement of the Globe

After determining the side, the globe is measured as follows:
1. Globe is measured in millimeters, first anteroposteriorly, then horizontally
and finally vertically
2. Cornea is measured in the horizontal and vertical meridian
3. The optic nerve length is then measured
4. Following which the pupil diameter is measured
This data forms the basis for pathologic reporting

c. Gross Inspection of the Eyeball

Gross inspection of the eyeball is made for superficial abnormality, e.g. site
of rupture of the globe, a scar or any growth, e.g. extrascleral extension of
a tumor. If such pathology is noted, its location and extent is described.

d. Transillumination
The transilluminator is used for transillumination of the globe. The globe is
transilluminated with a bright, point source of light in a dark room
6 MANUAL OF OCULAR PATHOLOGY

(Figure 1.2). The purpose is to identify and locate intraocular pathologic

processes, e.g. hemorrhages and tumors which are demarcated as
transillumination defects. The site and area of the transillumination defect
if found, is marked with a tissue tek pencil to decide the location of intraocular
pathology. Sectioning is done on the basis of these findings to include the
pathology in the calotte processed for study.

Figure 1.2: Transillumination of the globe

e. Sectioning of the Globe

Before sectioning, clinical summary is to be reviewed for the following
information, e.g. history of surgery, intraocular foreign body, suspected
intraocular tumor.
The globe is usually opened horizontally, but in case of previous surgery
which involves the limbal region, e.g. cataract, glaucoma or any other
operation, sectioning is done vertically to incorporate the surgical scar. For
the same reason, it is also cut in a different plane according to the lesion seen
clinically or by site of the transillumination defect.
The globe is opened by a new sharp razor blade for each eye, 2-4 mm on
either side of the optic nerve. During sectioning a right handed individual
holds the eyeball with the left hand with cornea placed down against the
cutting block. The razor blade is held between the thumb and middle finger
of the right hand. With a sawing motion, the eye is opened from behind,
2-4 mm away from the optic nerve moving to the front. The globe is opened
in a way that includes the pupil and optic nerve in the same section. This
is called pupil-optic nerve section (P-O section) of the globe (Figures 1.3A
to D).

f. Internal Description
The section of the globe called a calotte is then examined from anterior to
posterior as follows: (Figure 1.4).
 INTRODUCTION 7

Figures 1.3A and B: A. Showing an eyeball specimen with the forceps holding inferior oblique
muscle which indicates temporal side of the globe; B. Taking section of the globe through the
horizontal meridian cutting the superior calotte

Figures 1.3C and D: C. Taking section of the globe to obtain central calotte;
D. Showing the central calotte containing pupil and optic nerve

Figure 1.4: Normal eyeball

Cornea: Thickness
Anterior chamber: Normal or abnormal depth, any material inside
Vitreous cavity: Contents are examined
Retina: Peripheral cystoid degeneration is seen at the periphery close to ora
serrata in many eyes. Macula appears as a dark area on the temporal side
of the optic disk.
8 MANUAL OF OCULAR PATHOLOGY

Optic disk head: Any obvious pathology, e.g. color, swelling, cupping, etc. is
noted.
Choroid and sclera: Examined for any gross pathology, e.g. thickening, etc.
In case of any interesting findings, gross photography can be taken of the
calotte at this stage (Figure 1.3).
After the interior of the globe is examined, a second plane of section parallel
to the first is made again passing from back to front.
The other two calottes are examined for any gross pathology. The P-O
section is submitted for paraffin processing, the other two calottes are stored
and if needed can be studied later, on the basis of examination of the section
(Figure 1.5).

Figure 1.5: Gross photograph of the cut section of a globe showing thickening of a
choroid (arrow) in a case of sympathetic ophthalmia

Special Procedures
1. Retinoblastoma suspect: Optic nerve cross-section is taken at the end of the
surgical cut section prior to opening of the globe and submitted in a separate
cassette for processing. The patient’s prognosis, average life expectancy
and need for chemotherapy correlates with the extent of the tumor spread
into the optic nerve. Globe with long section of the optic nerve should be
taken during enucleation (Figure 1.6).

Figure 1.6: Showing gross photograph of the eyeball with long optic nerve
 INTRODUCTION 9
2. Malignant melanoma: The vortex vein is identified and a section is made
and submitted for processing to search for possible extrascleral extension
via vortex vein (Figure 1.7).

Figure 1.7: Gross photograph showing vortex vein in an eyeball with suspected malignant
melanoma of the choroid (arrow)

3. Intraocular foreign body: Prior X-ray of the globe should be done and after
sectioning, the foreign body should be looked for in the cut section. If found,
it should be removed, measured and preserved carefully in the file for
medico-legal reference.
4. In suspected calcification: Decalcification is necessary before sectioning.

g. Tumor Sample Collection for Molecular Biological Studies

Tumor samples excised from the patient eye is stored at -80°C for 30-60 minutes.
The tissue is dissected and immediately transferred to -80° C for protein analysis
in future and for RNA studies the tumor is processed for RNA extraction. For
gene expression studies the tissue is stored in liquid nitrogen for indefinite
period. MicroRNA expression studies the dissected tissue less than 0.5 cm is
submerged in RNA later solution are stored at 4°C overnight to allow
permeation of RNA later into cells and later shifted to -80°C for longer storage.

GROSSING OF OTHER SPECIMENS

Following steps are recommended:

Cornea
1. Measure the diameter in any meridian.
2. Examine both surfaces of the cornea under a dissecting microscope.
10 MANUAL OF OCULAR PATHOLOGY

3. Describe the corneal button in the following manner:

- Size in mm.
- Color, e.g. clear, mild and moderate haze or completely opaque.
- Any pathology observed, e.g. any opacity or ulcer, etc. If present, indicate
its size and position.
4. Make a rough diagram indicating the position of the pathology.
5. Cut the cornea into two halves in any meridian keeping the endothelial
surface up to protect the endothelium, as it is easier to rub off the delicate
endothelial surface than the epithelium which is multilayered.
6. Use a wax plated tray for cutting, to minimize damage to the surface.
7. Send one half of the specimen for paraffin processing and store the other
half.

Lens
1. Measurement of diameter
2. Description of the gross characteristics
3. Cut into two halves, one half can be submitted while the other half can
be saved.

IOL
1. Measurement of diameter
2. Make a note of pigmentation, deposits, etc.
3. Stain directly placing it in a concavity slide

Lid, Conjunctiva, Orbital or Uveal Tissue

1. Measurement in both axes
2. Maintain the orientation
3. Description of gross character
4. Bisect in the long axis symmetrically if the specimen is large enough. One
half is submitted to pathology and the other half is stored in the fixative
for future study, if required.

Stains Used in Ocular Pathology Lab (Table 1.1)

a. Routine staining
b. Microbiological staining
c. Special stains.
 INTRODUCTION 11
Table 1.1: Stains used in ocular pathology lab
a. Routine staining Stains used
Nuclei and cytoplasm Hematoxylin and eosin
b. Microbiological staining
Bacteria Brown Hopps method—Gram stain
Mycobacteria Ziehl-Neelsen stain
Fungi Gomori Methanamine Silver Stain (GMS), Periodic Acid
Schiff (PAS), Mucicarmine
c. Special stains
Connective tissue stain Masson trichrome stain, Van-Gieson stain, Reticulin
Mucin stain Mucicarmine, Alcian blue + PAS
Melanin Fontana – Masson, Schmorl’s, Dopa-oxidase
Iron Perl’s Prussian blue, Turn bull’s blue
Fat Oil Red O, Sudan Black
Calcium Von Kossa, Alizarin Red
Amyloid Congo Red
Glycogen Periodic Acid Schiff (PAS)

HANDLING OF SMALL BIOPSY SPECIMENS

Ophthalmic biopsy specimens are often small, and so require special attention
during processing. Dehydrated cucumber has been used effectively for
mounting tiny conjunctival and retinal biopsy specimens for proper
orientation. An agar-albumin tissue mount technique for the sterile recovery
and transport of small pieces of retina from the operating room to the
pathology laboratory has been described. In this technique the retinal biopsy
specimen is gently deposited in a sterile Petri dish filled with sterile balanced
salt solution and the tissue floated onto an agar mount. A drop of sterile liquid
albumin is dropped onto the mounted tissue and the specimen allowed to
stand for a few minutes before it is transferred to the desired fixative.
Tiny pieces of conjunctiva or iris tissue, which must be kept flat for proper
orientation, tend to roll up in formalin fixative. Such tissues are laid on filter
paper or a wooden tongue depressor by the surgeon, who indicates the
orientation of the specimen by a pencil drawing on the paper or on the
pathology requisition slip. In the laboratory the specimen can be pinned to
the paper or tongue depressor and placed in a large container of fixative.
Using this method the specimen stays flat and is easily removed from the
container. If the specimen is exposed to air for about 20s, it adheres to the
filter paper. The filter paper and the specimen then can be studied easily under
the dissecting microscope.
Small biopsy specimens tend to be lost from the cassettes during processing.
Therefore they should be wrapped in tissue paper before they are enclosed
in cassettes. If the specimen is only a maximum of 1-2 mm in size it may
be placed in the center of a circle marked on a paper and wrapped. Other
procedures, such as marking the specimen with blue tissue pencil or staining
it by presoaking in eosin help to identify the tissue during paraffin embedding
and sectioning.
12 MANUAL OF OCULAR PATHOLOGY

HISTOLOGIC SECTIONS
Following fixation the tissue is processed through a series of dehydration and
clearing steps and is embedded in paraffin in the desired direction so that
histological sections can be obtained through a plane that contains all tissue
layers, including the pathologic process. Care should be taken to orient the
block properly to prevent tears, folds and cellular distortion. Sections should
be of adequate thickness. Most ocular biopsy specimens are cut at 5-8 µm but
in suspected lymphoma cases thinner sections (3-4 µm) are preferred to make
the nuclear details clearer. Exenteration specimens or globes are usually
sectioned at 8-10 µm.
Ribbons of serial sections are taken and placed on cleaned glass slides lightly
coated with a tissue adhesive, such as chrome alum gelatin. Two or three
sections should be mounted and placed for staining on each slide. Routinely
two or three slides of hematoxylin and eosin (HE) and one of periodic acid-
Schiff (PAS) stain are prepared. Several histochemical or immunohistochemical
stains may be performed when necessary, but if several unstained slides can
be prepared at the time of sectioning for later special staining (e.g.
immunohistochemistry, fungi or bacteria), the tissue is used most effectively.

IMMUNOHISTOCHEMICAL STAINING
Examination of tissue sections with the conventional hematoxylin and eosin
stain and histochemical characterization with special stains may not be
sufficient to arrive at precise diagnosis. Immunohistochemical methods will
help in some of these instances by providing additional information. For
example, poorly differentiated or undifferentiated tumors can be identified
for the origin of tumor cell type by their specific cytoplasmic or surface
antigens, utilizing monoclonal or polyclonal antibodies directed to these
antigens. The conjugation of the antibody with the tissue antigens is then
detected by a fluorescent secondary antibody, by peroxidase or by other labeled
antibodies.
In the first of these methods, immunofluorescence, a fluorescence
microscope is needed to visualize the complex and the technique usually does
not allow for prolonged storage. Moreover, formalin-fixed tissue may not be
ideal for this technique because such tissue emits autofluorescence. Lens and
retinal pigment epithelium may also emit autofluorescence. The
immunoperoxidase technique is much more convenient for use with
ophthalmic specimens because it can be performed on formalin-fixed and
paraffin embedded tissue. This technique does not require a fluorescence
microscope and the stained sections can be stored for a long time. Modifications
of this method include the peroxidase-antiperoxidase (PAP) method or the
avidin-biotin complex (ABC) method, both of which have higher sensitivity
and specificity than the immunoperoxidase method.
14 MANUAL OF OCULAR PATHOLOGY

Eyelid consists of four main histological layers, from anterior to posterior

(Figure 2.1):
1. Skin
2. Orbicularis oculi muscle
3. Tarsus
4. Palpebral conjunctiva.

Figure 2.1: Normal eyelid histopathology showing skin, orbicularis

oculi muscle and tarsus (Trichrome stain)

Eyelid skin has the following characteristics:

- Absence of rete pegs
- Lanugo hair (without arrector pili)
- Absence of stratification of the dermis into clearly defined zones
- Absence of subcutaneous fat.

Histology
It has two parts:
• Epidermis
• Dermis.

a. Epidermis
Keratinized stratified squamous epithelium, composed of four layers of cells:
1. Keratin layer (stratum corneum)
2. Granular cell layer (stratum granulosum)
3. Squamous or prickle cell (stratum spinosum) layer
4. Basal cell layer (stratum germinativum).

b. Dermis
Important structures:
- Hair
- Glands
 PATHOLOGY OF THE EYELID 15
- Nerves
- Vessels.
Neoplasms may arise from any of these structures.
Pathological changes in lid lesions are as follows:
A. Hyperkeratosis: Thickening of the keratin layer.
B. Parakeratosis: Retention of nuclei within the keratin layer.
C. Dyskeratosis: Abnormal intraepithelial keratinization (Normally
keratinization occurs only at the surface of the epithelium).
D. Acanthosis: Thickening of prickle cell layer—A feature of hyperplasia of
epidermis.
E. Acantholysis: Separation of squamous cells by lysis leading to the formation
of an intraepidermal vesicle like a herpetic bulla.

Lid Lesions
Pathologic classification:
- Nonneoplastic
- Neoplastic

Nonneoplastic Lesions
I. Inflammation:
a. Infectious
– Bacterial—Hordeolum (stye), tuberculosis, syphilis, leprosy
– Viral—Molluscum contagiosum, human papilloma virus
– Fungal—Blastomycosis, coccidioidomycosis, aspergillosis, rhinospori-
diosis.
b. Non Infectious:
– Chalazion.
II. Degeneration:
– Xanthelasma
– Amyloidosis.
III. Cyst:
– Epidermoid inclusion cyst
– Dermoid cyst
– Sebaceous cyst
– Eccrine hidrocystoma
– Apocrine hidrocystoma (cyst of the gland of Moll).

Chalazion
It is a sterile foreign body lipogranulomatous inflammation caused by
extravasations of lipid material from either the meibomian gland of the tarsus
or glands of Zeis. Within the granuloma, clear spaces corresponding to lipid
material are seen along with multinucleated giant cells intermixed with
epithelioid cells, neutrophils and lymphocytes (Figures 2.2A and B).
16 MANUAL OF OCULAR PATHOLOGY

Figures 2.2A and B: A. Showing clinical photograph of chalazion of upper eyelid;

B. Photomicrograph of a chalazion showing giant cell with clear space within it (arrow)
corresponding to lipid material with multiple inflammatory cells

Viral Infections
a. Molluscum Contagiosum
It is caused by molluscum virus of the pox virus group. These are seen as
multiple, small, raised umbilicated pearly nodules along the lid margin (Figure
2.3A). On microscopic examination, the lesion consists of a lobulated collection
of acanthotic epithelial islands opening into a central crater. The squamous
cells contain characteristic eosinophilic cytoplasmic inclusion called
molluscum bodies (Figure 2.3B). Almost the entire cytoplasm is filled with
molluscum bodies and the nucleus is compressed at the periphery.

Figures 2.3A and B: Patient having multiple waxy dome-shaped umbilicated lesions of molluscum
contagiosum on eyelid as well as on face; B. Photomicrograph showing lobulated collection
of acanthotic epithelium opening into a central crater with multiple eosinophilic cytoplasmic
inclusions (Molluscum bodies) within the thickened epidermis (arrow)

b. Verruca Vulgaris
Viral warts are common in children and show acanthosis, papillomatosis,
hyperkeratosis and elongated peripheral rete ridges curve involved towards
the base of the lesion (Figure 2.4A). These lesions characteristically show
 PATHOLOGY OF THE EYELID 17
ground glass intranuclear inclusions, perinuclear vacuolation and
keratohyaline globules (Figure 2.4B).

Figures 2.4A and B: A. Showing hyperkeratosis, acanthosis and papillomatosis

of the epidermis in viral wart; B. High power view show ground glass intranuclear inclusions
and perinuclear vacuolation in verruca vulgaris

1. Xanthelasma—These consist of collections of histiocytes with foamy

cytoplasm, clustered around vessels and adnexal structures within the
dermis. It is seen in hyperlipidemia.
2. Amyloidosis—Amyloid deposits within the eyelid indicate a systemic
disease. It is seen as amorphous, eosinophilic, extracellular deposits usually
within the vessel wall but can also be present in connective tissue around
peripheral nerves and sweat glands. It can be demonstrated by Congo red
stain showing apple green birefringence on examination with polarized
light (Figure 2.5).

Figure 2.5: Showing apple green birefringence in a case of amyloidosis of the lid

Neoplastic Lesions
1. Tumors of the surface epithelium.
2. Tumors of the glands of the eyelid.
3. Vascular tumors
4. Neurogenic tumors
5. Melanotic tumors.
Tumors of the surface epithelium of the lid:
18 MANUAL OF OCULAR PATHOLOGY

Benign
1. Squamous papilloma (Figure 2.6)
2. Pseudoepitheliomatous hyperplasia
3. Inverted follicular keratosis
4. Keratoacanthoma
5. Seborrheic keratosis.

Figure 2.6: Showing squamous papilloma of the lid

Keratoacanthoma
This is a self-involuting lesion simulating squamous cell carcinoma clinically
as well as histopathologically.

Clinical
- Common in middle age or elderly people
- Solitary lesion
- Rapidly progressive lesion
- Involution occurs within a year leaving a depressed scar

Histopathology
It shows a cup-shaped invagination of well-differentiated squamous cells
forming irregular nests and strands inciting lymphocytic host response.
Seborrheic keratosis
- Common in middle age.
- Well circumscribed, oval to dome shaped lesion.
Histopathology: The epidermis show hyperkeratosis, acanthosis and
papillomatosis along with characteristic pseudohorn cysts which are
concentrically laminated collections of surface keratin within the acanthotic
epithelium (Figure 2.7).
 PATHOLOGY OF THE EYELID 19

Figure 2.7: Photomicrograph showing hyperkeratosis and acanthosis of

epidermis along with numerous pseudohorn cysts

Malignant:
1. Basal cell carcinoma
2. Squamous cell carcinoma.
Basal cell carcinoma:
This is the most common eyelid tumor (39 times more common than squamous
cell carcinoma).
Location (according to frequency) — Lower lid, upper lid, medial canthus,
lateral canthus.
Clinical presentations:
- Nodular
- Noduloulcerative (Figure 2.8)
- Cystic
- Sclerotic (morphea form)
- Pigmented (can be confused with melanoma).

Figure 2.8: Clinical photograph of a case of basal cell carcinoma (rodent ulcer)
20 MANUAL OF OCULAR PATHOLOGY

Histopathology:
Nodular—Nests and cords of proliferating epidermal basilar cells (Figures 2.9A
and B).
Noduloulcerative type - Peripheral palisading of tumor cells.
- Collagen deposition in the dermis.
- Separation of nests of tumor and dermal tumor
stroma (retraction space or cracking artefact).
- Central necrosis.
Cystic type - Sometimes cysts are filled with blood or
degenerating blood products such as hemosiderin.
Morphea type - Tumor tends to penetrate in the dermis, diffusely
branching cords of cells.
Spread—Mainly local into periorbital and orbital structures.
Metastasis - Extremely rare.
- Directly invasion of the cranial cavity can lead to
secondary metastasis.

Figures 2.9A and B: A. Showing multiple islands of basaloid cells within the dermis;
B. High power review showing peripheral palisading and cracking arteacts (arrow) in a case
of basal cell carcinoma

Squamous Cell Carcinoma

Common in elderly fair-skinned patients, the lower eyelid being more
frequently involved. The majority of squamous cell carcinoma arise in solar
damaged skin (actinic keratosis).
Clinical appearance is diverse, ranging from ulcers to plaque formation
to fungating or nodular growth (Figure 2.10A).

Pathology
Progress through phases:
i. Intraepithelial squamous dysplasia:
- Partial thickness replacement of epithelium by atypical cells.
ii. Intraepidermal squamous cell carcinoma (carcinoma in situ):
 PATHOLOGY OF THE EYELID 21
- Full thickness replacement of epithelium by malignant epithelial cells
without invasion beyond basement membrane of epithelium (Figure
2.10B).
iii. Invasive squamous cell carcinoma:
- These atypical squamous cells forms nests and strands, break the
epithelial basement membrane, infiltrate into dermis and incite a
desmoplastic fibrous tissue reaction (Figure 2.10C).

Figures 2.10A to C: A. Patient showing cauliflower likes growth from the lower eyelid;
B. Full thickness replacement of epithelium with malignant squamous cells with intact basement
membrane, suggestive of severe conjunctival dysplasia (carcinoma in situ); C. Showing multiple
nest of malignant squamous cells invading into the dermis in a case of squamous cell carcinoma

Pathology of Hair and Glands of Eyelid

Hair:
- Pilar cyst
- Trichoepithelioma
- Trichofolliculoma
- Tricholemmoma
- Pilomatrixoma.
Glands:
- Eccrine glands (sweat glands)
- Sudoriferous cyst
- Syringoma
- Apocrine glands (glands of Moll)
- Apocrine hidrocystoma.
Sebaceous glands (Meibomian glands, glands of Zeis):
- Sebaceous hyperplasia
- Sebaceous adenoma
- Sebaceous gland carcinoma.
Sebaceous gland carcinoma:
Origin:
- Meibomian glands
- Glands of Zeis
- Glands associated with caruncle.
22 MANUAL OF OCULAR PATHOLOGY

Occurrence:
- Elderly (rare before 40 years)
- More common in females
- More in Asians (Chinese).
- Predilection for eyelids (extremely rare elsewhere in the body).

Types of Presentation
1. Solitary nodule – mimics chalazion
2. Diffuse spread to surface skin or conjunctiva.
- Chronic blepharitis or chronic blepharoconjunctivitis.
- Loss of cilia
- Yellow secretions (masquerade syndrome).
Site: Upper eyelid is involved in 2/3rd of cases. It may be multicentric –
involving both lower and upper eyelid.
Microscopic examination:
• Lesion is extensive infiltrative and has lobular pattern (Figure 2.11A)
• Tumor cells have abundant finely vacuolated, foamy cytoplasm showing
sebaceous differentiation (Figure 2.11B).

Figures 2.11A and B: A. Clinical photograph showing case of sebaceous gland carcinoma
presenting as a single yellow nodule from lower eyelid; B. Photomicrograph of the tumor showing
nuclear pleomorphism with cytoplasmic lipid droplets indicating sebaceous differentiation

• This sebaceous differentiation is more conspicuous in the center of lobules

with less differentiation at the periphery.
• Pagetoid spread to adjacent skin, conjunctival and lid epithelium and cornea
is very common (Figure 2.12A)
• Demonstration of the lipid within the cytoplasm of tumor cells is confirmed
by special stains like oil red O on frozen section (Figure 2.12B) or Sudan
black.
Poor prognostic factors include:
- Tumor size > 10 mm
- Multicentricity
- Highly infiltrative growth factor
 PATHOLOGY OF THE EYELID 23
- Pagetoid epithelial infiltration
- Vascular invasion.

Figures 2.12A and B: A. Sebaceous gland carcinoma with pagetoid spread; B. Photomicrograph
of the tumor cells containing lipid droplets in the frozen section stained with Oil Red O

Vascular Tumors of the Eyelid

Angiomatous Lesions
1. Congenital:
i. Port wine stain – nevus flammeus
ii. Strawberry nevus (capillary hemangioma).
2. Lymphangiomatous lesion – lymphangioma
3. Kaposi’s sarcoma
4. Angiosarcoma.

Neurogenic Tumors
1. Neurofibroma
2. Schwannoma.

Melanotic Tumors of the Eyelid

- Nevus
- Malignant melanoma.

Malignant Melanoma
- 1% of all eyelid malignancies.
- Associated with preexisting nevus or may develop de novo.
- Clinically appears as a flat to nodular lesion with a variable degree of
pigmentation.
There are 4 main histopathological subtypes:
1. Superficial spreading
2. Lentigo maligna
3. Nodular
4. Acral lentiginous.
24 MANUAL OF OCULAR PATHOLOGY

1. Superficial spreading: (pagetoid melanoma) – Consists of atypical

melanocytes with pale cytoplasm arranged singly and in nests at all
levels of the epidermis.
2. Lentigo maligna: A linear proliferation of spindle-shaped atypical
melanocytes along the basal layer of the epidermis extending into the
upper epidermis and downward to involve pilosebaceous units.
3. Nodular: Atypical melanocytes always involve the dermis and are
composed of large anaplastic epithelium.
4. Acral lentiginous: In extremities and rarely seen in eyelid.

Cystic Lesions of the Eyelid

- Sweat Gland Cysts
- Epidermal inclusion cyst
- Dermoid cyst
- Cystic basal cell carcinoma.
26 MANUAL OF OCULAR PATHOLOGY

HISTOLOGY
Epithelium
- Stratified columnar—general
- Stratified squamous—limbus, lid margin
- Goblet cells—secrete mucin, an essential component of tear film, stains
positive with PAS stain.

Stroma
- Fibrovascular connective tissue
- Fibroblasts, melanocytes
- Chronic inflammatory cells
- Lymphoid follicles and accessory lacrimal gland.

Pathology
- Congenital
- Inflammation
- Degeneration
- Cysts
- Neoplasm
- Changes in systemic diseases.

Congenital
- Dermoid
- Dermolipoma
- Ataxia telangiectasia.

Dermoid
Choristomatous mound of coarsely thickened collagen fibers covered by skin-
like epithelium, containing epidermal appendages (hair, sebaceous and sweat
glands).
The following types of dermoid are seen in the conjunctiva:
i. Isolated dermoid: Choristoma is seen alone.
ii. In association with Goldenhar syndrome: Epibulbar solid dermoids,
preauricular appendages, aural fistulas.
iii. Dermolipoma: Dermoid choristoma composed primarily of fatty tissue.

Inflammation
i. Acute conjunctivitis
True Membrane
- Inflammatory exudates firmly adherent to epithelium.
- Bleeding occurs when membrane is peeled, e.g. Diphtheria, Gonococcus.
 PATHOLOGY OF THE CONJUNCTIVA 27
- Stevens-Johnson syndrome.
Pseudomembrane
- Less adherent, can be peeled without bleeding.
Causes:
- Viral (HSV, Adenovirus 8, Adenovirus).
- Bacterial (Staphylococcus, Pneumococcus, Meningococcus, Pseudomo-
nas, Coli forms).
- Chemical burns, ocular pemphigoid, foreign body, ligneous
conjunctivitis.
ii. Chronic conjunctivitis:
Ligneous conjunctivitis:
- Bilateral, chronic pseudomembranous conjunctivitis is seen in children.
- Massive, woody accumulation of fibrin with chronic inflammatory cells.
Similar lesions may be seen in the vagina and other mucosal structures.

Pathological Classification
Follicular conjunctivitis Develops insidiously.
The inflammatory response consists of
lymphocytes and plasma cells.
Follicles are composed of aggregates of
lymphocytes and plasma cells. Lymphocytes
may form germinal centers within the follicles.
It is seen in bacterial, viral and chlamydial
infections as well as with toxins.
Papillary conjunctivitis It shows a cobblestone arrangement of flattened
nodules with a central vascular core. It is
commonly associated with allergic or vernal
conjunctivitis and part of a foreign-body
reaction.
iii. Vernal conjunctivitis—Bilateral, recurrent conjunctivitis in adolescents
with history of atopy.

Pathology
- Worsens in spring, marked itching–chronic papillary hypertrophy.
- Epithelial hypertrophy, then atrophy.
- Fibrovascular papillary core which contains perivascular and diffuse
infiltration of lymphocytes, plasma cells and numerous eosinophils.

iv. Giant papillary conjunctivitis - Seen in soft contact lens wearers. When
the papillae become large sized, it’s
called giant papillary conjunctivitis.
v. Conjunctival tuberculoma— Very rare. It can be seen in HIV positive
patients as a conjunctival mass lesion
28 MANUAL OF OCULAR PATHOLOGY

(Figure 3.1A). Histopathology shows

caseating granulomatous inflammation
with multiple giant cells (Figure 3.1B).

Figure 3.1A: Showing a lobular conjunctival mass in a case of

conjunctival tuberculosis

Figure 3.1B: Photomicrograph showing multiple granuloma along with a

Langhans type of giant cell (arrow)

vi. Conjunctival rhinosporidiosis— It presents as a conjunctival or scleral

mass. Histopathology shows multiple
sporangia (Figures 3.2A and B).

Figures 3.2A and B: A. Showing scleral staphyloma due to rhinosporidiosis;

B. Rhinosporidiosis of conjunctiva with multiple sporangia (arrow)
 PATHOLOGY OF THE CONJUNCTIVA 29
CONJUNCTIVAL DEGENERATIONS
Pterygium and Pinguecula
Raised yellowish white mound of degenerated subepithelial connective tissue
near the limbus in the interpalpebral space. It is probably related to damage
by environmental exposure to sunlight. Pterygiums are characterized by a
wing like encroachment of the conjunctiva on to the cornea (Figure 3.3A).

Pathology
- Solar elastosis, acellular homogenous deposit, basophilia, thickened
vermiform collagen fibers (Figure 3.3B).
- Stains positive with Verhoeff-Van Gieson elastic stain.

Figures 3.3 Aand B: Clinical photograph showing wing-like configuration of conjunctiva

on cornea in a case of pterygium; B. Histopathologically both pterygium and pinguecula show
elastotic degeneration of stromal collagen (arrow)

Cysts
i. Inclusion cyst: It is an empty or mucus-filled lumen lined by conjunctival
epithelium and caused by trauma or surgical implantation.
ii. Ductal cyst: This is an analogue of sudoriferous cysts in the skin. It is
lined by a dual layer and has a clear lumen. It arises from the accessory
lacrimal glands.

Tumors
There are three basic categories:
i. Squamous lesions—proliferation of epithelium
ii. Lymphoid lesions—proliferation of normal resident population of
lymphocytes
iii. Melanocytic tumors.

Squamous Lesions
Types
i. Squamous papilloma
ii. Conjunctival dysplasia
30 MANUAL OF OCULAR PATHOLOGY

iii. Carcinoma in situ

iv. Invasive squamous cell carcinoma.

i. Squamous papilloma
• Bulbar or palpebral conjunctival swelling (Figure 3.4)
• Can be multiple and recurrent, especially in children
• Many are viral lesions (papilloma virus)
• Vascular ‘Hairpin’ loops are seen clinically.

Figure 3.4: Conjunctival papilloma, multiple red dots correspond to fibrovascular core

Pathology
- Benign proliferation of conjunctival epithelium as multiple fronds with
central fibrovascular cores (Figure 3.5).

Figure 3.5: Photomicrograph showing multiple fronds of acanthotic epithelium with central
fibrovascular core in a case of conjunctival papilloma

Note: Conjunctival dysplasia or squamous cell carcinoma can have

papillomatous configuration.
 PATHOLOGY OF THE CONJUNCTIVA 31
ii. Conjunctival Dysplasia
Disease spectrum characterized by replacement of conjunctival epithelium
by atypical squamous cells.
- Basal germinative layer involved first
- Abrupt transition between normal and acanthotic dysplastic epithelium
frequent.
- Mild dysplasia: <50% of epithelium is replaced by atypical squamous cells.
- Severe dysplasia: >50% of epithelium is replaced by atypical squamous
cells (Figure 3.6).

Figure 3.6: Showing severe conjunctival dysplasia.

Note intact basement membrane (arrow)

iii. Carcinoma in situ

- Total replacement of epithelium by malignant cells
- Epithelial basement membrane is intact
- No invasion into substantia propria
- Spindle and epidermoid variants.

iv. Invasive Squamous Cell Carcinoma

Malignant cells have broken through epithelial basement membrane and have
invaded substantia propria (Figures 3.7A and B).
- May have papillary growth pattern
- Can invade interior of globe, lid and orbit
- Rarely metastasizes.
32 MANUAL OF OCULAR PATHOLOGY

Figures 3.7A and B: A. Conjunctival squamous cell carcinoma; B. Photomicrograph showing

dyskeratotic epithelium and multiple keratin pearls in a case of conjunctival squamous cell
carcinoma

Lymphoid Tumors
- These arise from the conjunctiva’s resident population of lymphocytes
(Figure 3.8).

Figure 3.8: Slit lamp photograph showing diffuse fleshy lesion in a

case of conjunctival lymphoma

Benign Lesions (Reactive lymphoid hyperplasia)

- Lymphoid follicles with germinal centers
- Abundant capillaries with plump endothelial cells
- Polymorphous infiltrate containing a mixture of cells, i.e. mature
lymphocytes, plasma cells and eosinophils (Figure 3.9)
- Polyclonal infiltrate with immunohistochemical markers/DNA ploidy
studies/T cell receptor gene rearrangement studies.

Malignant Lesions (Malignant lymphoma)

- Monomorphic infiltrates
- Atypical lymphoid cells
- Monoclonal on immunohistochemistry with T and B cell markers.
Note: Immunophenotyping of conjunctival lymphoma is important to identify
MALT lymphomas, mantle zone lymphomas, etc.
 PATHOLOGY OF THE CONJUNCTIVA 33

Figure 3.9: Photomicrograph showing monomorphic population of

lymphoid cells in a case of conjunctival lymphoma

Melanocytic Tumors
Nevi: Congenital lesion – may enlarge or become more pigmented during
pregnancy or puberty, these being cosmetic indications for excision (Figs 3.10
A and B).
There are 3 main variants:
- Junctional: Nevus cells confined to epithelial subepithelial junction (can be
impossible to distinguish from acquired melanosis in small biopsy without
good history).
- Subepithelial: Nevoid nests confined to substantia propria.
- Compound: Nevus cells in both epithelium and substantia propria.

Figures 3.10A and B: A. Showing conjunctival nevus; B. Showing cystic

nevus of the conjunctiva

Primary Acquired Melanosis (PAM)

Unilateral flat or patchy of golden brown pigmentation with an irregular
margin seen in the middle-aged or elderly.
a. PAM without atypia shows hyperplasia of melanocytes without atypical
features concerning cytology or cell architecture
b. PAM with atypia—It shows nuclear enlargement and may be spindled,
polygonal or epithelioid. Architectural features of atypia include
34 MANUAL OF OCULAR PATHOLOGY

lentiginous hyperplasia, intraepidermal migration of individual cells or

nests or complete replacement of epithelium mimicking carcinoma in situ.
Approximately 2/3rd of cases of conjunctival melanomas arise from PAM
with atypia.

Malignant Melanoma
- Relatively rare (Uveal: Conjunctival melanoma ratio is 10:1)
- 25% mortality and unpredictable behavior.
- Can arise from:
- Acquired melanosis (most)
- Preexisting nevus
- De novo (nodular melanoma).
- Acquired melanosis found in 75%, Nevi 25%.
- Behave like skin, not uveal melanomas (Calendar classification not
applicable to conjunctival melanomas).
- Malignant tumor cells with melanin pigments in the stroma.
- Lymphatic spread common (preauricular and intraparotid nodes).
36 MANUAL OF OCULAR PATHOLOGY

Host’s corneal button is obtained during keratoplasty procedure and is

subjected to histopathological examination. Other corneal specimens include
corneal biopsy obtained by lamellar keratectomy and corneal scrapings.

HISTOLOGY
Normal cornea is composed of laminated collagenous tissue lined on both
sides by a membrane and a cellular layer. There are five layers of cornea (Figure
4.1).

Figure 4.1: Photomicrograph showing histology of normal cornea comprising of epithelium,

Bowman’s membrane, stroma, Descemet’s membrane and endothelium

1. Epithelium
2. Bowman’s membrane
3. Stroma
4. Descemet’s membrane
5. Endothelium.
Epithelium: It is composed of five cell layers of nonkeratinized stratified
squamous epithelium which is continuous with the conjunctival epithelium.
Beneath the epithelium, a thin basement membrane is present which can be
easily seen by PAS stain.
Bowman’s membrane: It is a homogenous layer of 10 mm thickness. It is not
a true membrane but an acellular condensation of the anterior corneal stroma.

Stroma: It constitutes the major portion of the cornea and is composed of very
regularly arranged lamellae, of collagen fibers. Between the lamellae, spindle-
shaped fibroblast-like cells are seen, known as keratocytes.
Descemet’s membrane: It is a true basement membrane about 10 mm thick, best
seen with PAS stain.

Endothelium: It is a single layer of cuboidal cells derived from the neural crest.
 PATHOLOGY OF THE CORNEA 37
Pathology of cornea can be studied systematically looking from above
downwards as described below:

Epithelium
1. Arrangement:
a. Regular or irregular.
b. Loss of epithelium—partial or total (one should keep in mind that it
could be artifactual during initial cutting or during microtome
sectioning). Partial or full thickness loss with underlying stromal tissue
shrinkage is seen in Dellen.
2. Thickening and epidermadization: Vitamin A deficiency.
3. Exposure keratitis: Intraepithelial cyst formation.
4. Elevation: Epithelium raised from underlying structures, e.g. bullae
formation, seen typically in bullous keratopathy.
5. Pannus: Fibrous or fibrovascular tissue underneath the epithelium can occur
due to chronic inflammation along with concurrent destruction of
Bowman’s membrane or in noninflammatory conditions without
destruction of Bowman’s membrane e.g. advanced bullous keratopathy.
6. Band keratopathy: Deposition of calcium in epithelial basement membrane,
Bowman layer and anterior stroma which is characteristically seen as sub
epithelial basophilic granular degeneration in band-shaped distribution
with hematoxylin and eosin stain (Figure 4.2) and confirmed by the use
of special stains such as Alizarin Red or Von-Kossa satin. It occurs in chronic
inflammation and glaucoma.

Figure 4.2: Band keratopathy showing deposition of calcium in epithelial basement

membrane, Bowman’s layer and anterior stroma

7. Bullous keratopathy: It is characterized by edema of corneal stroma and

epithelium. The epithelium is separated from the underlying Bowman’s
layer creating micro cyst or bullae (Figure 4.3). It is seen in long-standing
stromal edema with loss of active function of endothelium.
38 MANUAL OF OCULAR PATHOLOGY

Figure 4.3: Bullous keratopathy showing swelling of the corneal epithelial cells (epithelial
edema), a large bullae is present between the epithelium and Bowman layer

8. Pigment deposit: Iron is found in the basal epithelial cells and can be
demonstrated by using the Prussian blue stain.

Stroma
Look for staining character, e.g. pale staining is observed in corneal edema.
Normal cornea will show multiple areas of separation of stromal lamellae
due to dehydration during processing. This is a meaningful artifact.
1. Edema: Lack of lamellar separation indicates corneal edema. In advanced
cases, the keratocyte density is diminished. Epithelial edema is accompanied
in most cases.
2. Vascularization: Vascular lakes are seen with RBCs inside. The location of
vessels is noted, e.g. superficial or deep, in the central or peripheral portions.
3. Inflammation:
i. Ulcerative: There is destruction of epithelium and Bowman’s membrane
with invasion of acute and chronic inflammatory cells.
ii. Non-ulcerative: Interstitial keratitis: non-ulcerative keratitis accompanied
by vascularization, e.g. syphilis.

1. Infections
A. Bacterial
Modified Grams stain (Brown-Brenn or Brown-Hopps) can be used for
identification. Gram-negative organisms will stain red and gram-positive
organisms will stain blue. Common bacteria which cause keratitis are
Staphylococcus aureus, Streptococcus pneumoniae, and Pseudomonas aeruginosa.
Atypical mycobacteria may rarely cause keratitis and can be stained by Ziehl-
Neelsen stain.

B. Fungal
Organisms can be identified with Gomori’s methenamine silver stain (Figure
4.4), calcoflour or lectin staining. The most common organisms are Aspergillus,
Candida and Fusarium.
 PATHOLOGY OF THE CORNEA 39

Figure 4.4: Fungal keratitis with multiple septate fungal hyphae

(Gomori’s methenamine silver stain)

C. Viral
Herpes simplex and herpes zoster. Herpes simplex keratitis occurs in three
distinct clinical forms:
i. Dendritic
ii. Disciform
iii. Necrotizing interstitial.
I. Dendritic: Self-limited epithelial disease characterized by linear arborizing
pattern of opacification and swelling of epithelium (dendrite). Corneal
scraping from dendrite reveals the presence of intranucelar viral
inclusion by Giemsa stain.
II. Disciform: It is thought to be caused by cell-mediated immune response
to viral antigens, although sometimes viral particles are seen. It can also
be due to herpes zoster, varicella, vaccinia, etc.
III. Necrotizing interstitial: Sometimes full thickness stromal involvement and
granulomatous reaction in the region of Descemet’s membrane is seen.

D. Protozoal (Acanthamoeba)
A free living, nonparasitic protozoan is found in fresh and salt water, soil
and air. Direct corneal contact with contaminated contact lens solution or
water results in such infection. The organism has trophozoite and cyst forms.
The cyst has a characteristic appearance with a double wall. The outer being
wrinkled and the inner round. The cyst can be seen with the H&E, PAS and
calcoflour stains, KOH preparation and by immunohistochemical methods.
It causes a chronic progressive keratitis, that often mimicks viral, fungal or
bacterial keratitis.
40 MANUAL OF OCULAR PATHOLOGY

2. Dystrophies
Corneal dystrophies are a group of disorders that are primary, bilateral,
symmetrical, avascular and often hereditary. They are classified according
to the principal layers involved.
i. Epithelial (e.g. map dot-finger print): Primary epithelial adhesion, epithelial
reduplication, bullae, folding and excessive sub or intraepithelial
basement membrane production.
ii. Stromal: Stromal dystrophies have characteristic clinical presentation and
specific type of histochemical characteristics as outlined below:

Stromal dystrophies Inheritance Types of Special stain used

degeneration
Lattice (Figures Autosomal Amyloid Congo red (when viewed
4.5A and B) dominant degeneration with polarized light, it
produces apple green
birefringence)
Granular (Figures Autosomal Hyaline Masson’s trichrome (it stains
4.6A and B) dominant degeneration the dystrophic portion
intensely red)
Macular (Figures Autosomal Mucoid Deposits stain blue for
4.7A and B) recessive degeneration acid mucopolysaccharide
with alcian blue and colloidal
iron

Figures 4.5A and B: A. Lattice corneal dystrophy; B. Lattice dystrophy showing apple green
birefringence of stromal deposits in a Congo red stained section viewed with polarized light

Figures 4.6A and B: A. Granular corneal dystrophy; B. Granular deposits (stained red)
are present in the stroma and beneath the epithelium (Masson trichrome stain)
 PATHOLOGY OF THE CORNEA 41

Figures 4.7A and B: A. Macular corneal dystrophy; B. Macular dystrophy showing

superficial deposits staining positive (blue) with alcian blue stain

3. Degeneration
May be actinic keratopathy, spheroidal degeneration or labrador keratopathy.
It is seen as basophilic globules in the superficial stroma (Figure 4.8). It is
due to damage to the corneal collagen.

Figure 4.8: Climatic keratopathy showing multiple lightly stained basophilic

globules (arrow) in superficial stroma

4. Blood Staining of the Cornea

It may follow a hyphema associated with raised intraocular pressure.
Microscopically, the free hemoglobin and its breakdown product appear as
red or orange globules in between corneal lamellae (Figures 4.9A and B).

Figures 4.9A and B: A. Blood staining of cornea; B. Blood staining of the cornea.
Numerous small orange red particles are scattered within the stromal lamellae of the cornea
42 MANUAL OF OCULAR PATHOLOGY

Corneal Graft Rejection

Homograft rejection - Central corneal degeneration, sharply demarcated
zone.
Stromal rejection - Polymorphonuclear leukocytes centrally and surrounded
by lymphocytes and plasma cells peripherally.
Graft failure - Diffuse stromal edema with other changes, e.g. epithelial
thinning or loss, stromal scarring and vascularization and
decrease or loss of endothelial cells.

Descemet’s Membrane
1. Thickening: It is thickened in various diseases, e.g. Bullous keratopathy
and endothelial dystrophy.
2. Pigment deposition, e.g. Kayser-Fleischer ring—The brown ring seen in
the periphery of the cornea in Wilsons disease, which corresponds to copper
deposition in the Descemet’s membrane.

Endothelium
During processing endothelial cells may be lost. Examination of the other
layers of the cornea will help to distinguish artificial from actual endothelial
cell loss. Endothelial cell loss can occur in the following conditions.
1. Intraocular surgical procedure:
a. Cataract extraction – more often with intracapsular than extracapsular.
b. Cataract with IOL implantation – more after anterior chamber lens
implantation.
c. Penetrating keratoplasty.
2. Trauma.
3. Glaucoma.
4. Inflammations involving the anterior chamber, e.g. iridocyclitis.
5. Dystrophy:
i. Fuch’s endothelial dystrophy (Figure 4.10): Abnormal basement
membrane material, secreted on Descemet’s membrane (guttae).

Figure 4.10: Fuch’s endothelial dystrophy. Endothelium is absent. Descemet’s membrane

is thickened with numerous excrescences (guttae)
 PATHOLOGY OF THE CORNEA 43
ii. Congenital hereditary endothelial dystrophy:
- Thickened edematous stroma
- Descemet’s membrane is markedly thickened.

Keratoconus: It is a noninflammatory condition characterized by bilateral central

ectasia of the cornea and histological changes which include, focal disruption
of epithelial basement membrane and Bowman layer with central stromal
thinning and anterior stromal scarring (Figure 4.11). The Descemet’s
membrane can be ruptured sometimes (corneal hydrops). Iron deposits in
the basal epithelial layer can be demonstrated by the Prussian blue stain.

Figure 4.11: Keratoconus: Low magnification showing central stromal thinning and scarring

Structures Adherent to Corneal Surface

1. Retrocorneal membrane—occurs in two ways:
a. After chemical or inflammatory insult to the cornea where Descemet’s
membrane is intact.
b. After surgical or accidental perforating corneal wounds where
Descemet’s membrane is broken.
2. Iris tissue seen in adherent leukoma.
3. Hypopyon—acute inflammatory cells.
4. Keratitic precipitates—lymphocytes, epithelioid cells.
5. Epithelial ingrowth—after cataract or other intraocular surgery and trauma.
6. Pigment deposition—Melanin pigments located within the endothelial cells.
(Krukenberg spindle) as well as on the posterior corneal surface. It is seen
in pigment dispersion syndrome.
46 MANUAL OF OCULAR PATHOLOGY

The crystalline lens is a soft elastic, avascular structure that measures 9-10
mm in diameter and 3.5 mm in anterior posterior thickness.

HISTOLOGY OF LENS
- Unique tissue in the body.
- It is a derivative of a single primitive tissue (surface ectoderm).
- The surface epithelium grows inwards at the equator—so it sheds its
epithelium inwards and forms lens fibers.
- It becomes compact with age—following which yellow pigments are
deposited on it to form cataracts.
- The lens capsule is the thickest basement membrane in the human body.

PATHOLOGY
It is of 4 types:
I. Zonular alterations.
II. Capsular alterations.
III. Epithelial changes.
IV. Lens substance alterations.

I. Zonular Alterations
- Subluxation.
- Dislocation.

Marfan’s Syndrome
An autosomal dominant condition, it is disorder of connective tissue in which
there is spontaneous subluxation of lens in a superotemporal direction. Other
phenotypical features include, long slender extremities, musculoskeletal
deformities and cardiovascular changes.

Pathology
- Hypoplasia of dilator muscles.
- Ciliary processes are often elongated and extending from the anterior to
the posterior surface of the iris.

Homocystinuria
Inferonasal displacement of the lens.

Weill-Marchesani Syndrome
Superotemporal or temporal displacement of a spherophakic lens.
 PATHOLOGY OF THE LENS 47
II. Capsular Alterations
Exfoliation can be true or pseudo
True:Steel workers
Glass blowers.
- The most anterior layer of the anterior capsule splits into several layers.
- These split layers are seen as scrolls.

Pseudo Exfoliation Syndrome

- Mucoproteinaceous material
Also seen in:
- Zonules
- Ciliary epithelium
- Iris
- Trabecular meshwork.

Histology
- Amorphous eosinophilic floccular deposits
- Stains with acid mucopolysaccharide stain.
Coronary cataract: Consist of wart-like excrescences on the capsule, which with
time are replaced by clumps of epithelium, resulting in granular debris in
the peripheral cortex.

III. Epithelial Changes

- Degenerations
- Proliferations
a. Subcapsular cataract (Figure 5.1)—local proliferation and metaplasia of
lens epithelium.

Figure 5.1: Subcapsular proliferation of lens epithelial cells in

anterior subcapsular cataract

b. Elschnig’s pearls—numerous small globular structures over the inner

surface of the posterior capsule, resembling fish eggs.
48 MANUAL OF OCULAR PATHOLOGY

Origin: From the remnants of epithelium bearing anterior capsule which

migrate posteriorly and try to form new lens fibers and cover the inner
surface of posterior capsule.
c. Siderotic cataract: Iron deposits are seen in the subcapsular region. It stains
blue with Prussian blue stain (Figure 5.2).

Figure 5.2: Iron deposits are seen in the subcapsular region in siderotic cataract
(Prussian blue stain)

d. Soemmering’s ring cataract (Figure 5.3): Dense opaque lens cortex forms
a ring behind the iris.

Figure 5.3: Sequestrated proliferating lens fibers in the equatorial

region in Soemmering’s ring cataract

IV. Lens Substance Alterations

Nuclear Sclerosis
- Center of the lens collects all degenerated epithelial cells as insoluble
proteins
- Residues of cellular organelles
- Urochrome pigment – filters blue light
- Dark brown – Brunescent cataract
 PATHOLOGY OF THE LENS 49
- Black – Cataract nigra
- Histology – homogenously eosinophilic with a loss of normal artifactious
clefts.

Cortical Cataract
- Fragmentation of lens fibers.
- Morgagnian globules—Small round globules caused by fragmentation of
lens fibers.
- Liquefaction of lens fibers (Figure 5.4).

Figure 5.4: Lens fibers showing extensive cortical degeneration in cortical cataract

Hypermature Cataract
It is of two types:
1. Morgagnian—Lens capsule contained liquefied cortex–nucleus resting on
dependent portion of the lens.
2. Sclerotic—Fluid leaked out.
52 MANUAL OF OCULAR PATHOLOGY

Uveitis is considered to be an endogenous or exogenous inflammation of the

uveal tract, i.e. the middle coat of the eye which comprises of iris, ciliary body
and choroid. The pathological study of uveitis is often not done as most often
the diagnosis is established clinically and by noninvasive investigations, e.g.
laboratory tests. However, in some situations, microscopic study of specimens
from the anterior chamber, vitreous cavity or biopsy of iris, retinochoroidal
tissue is needed for diagnosis and management. Clinicopathological
correlation can be done in cases where eyes of uveitis patients are removed
for some reason or obtained during autopsy (especially in AIDS patients).
Pathologically two types of inflammation are seen:
1. Nongranulomatous, e.g. uveitis in ankylosing spondylitis
2. Granulomatous, e.g. tuberculosis, sarcoidosis.

GRANULOMATOUS
Three pathological types of granulomatous inflammation are encountered
in uveitis and are given below:
Pathologic type Diagnosis
1. Zonal Lens induced uveitis, tuberculosis
2. Diffuse Sympathetic ophthalmia
3. Discrete Sarcoidosis

Sympathetic Ophthalmia and Vogt-Koyanagi-Harada (VKH) Syndrome

Sympathetic ophthalmia is a unique disease, where diffuse granulomatous
panuveitis occurs a few to several years after a penetrating wound or surgical
trauma to the eye. VKH is a bilateral granulomatous uveitis with exudative
retinal detachment. Multiple organs, e.g. ear, skin and central nervous system
are also affected in VKH commonly. Sympathetic ophthalmia and VKH
resemble each other histopathologically. There was also no difference
histologically in the exciting eye (the eye with the injury) and the sympathizing
eye in sympathetic ophthalmia (Figure 6.1).

Figure 6.1: Microphotograph showing Dalen Fuchs nodule with diffuse inflammation of the choroid
in a case of sympathetic ophthalmia (arrow) (Courtesy: Dr Deepak Edward, USA)
 PATHOLOGY OF THE UVEA 53
The following histopathologic characteristics are seen in these two uveitic
entities:
i. Diffuse lymphocytic infiltration of the choroid with epithelioid cells and
occasional giant cells.
ii. Focal chorioretinal scar.
iii. Pigment migration in the disorganized retina.
iv. Pigment phagocytosis of epithelioid cells.
v. Dalen-Fuchs nodule: Focal collections of epithelioid cells, macrophages
and lymphocytes between the retinal pigment epithelium and Bruch’s
membrane.
vi. Neutrophils, plasma cells and eosinophils occasionally.
vii. Sparing of choriocapillaries was earlier thought to be specific for
sympathetic ophthalmia and not for VKH. As eyes with sympathetic
ophthalmia are removed earlier than VKH cases, such a difference can
be seen histopathologically and the finding should not be considered
to be a differentiating feature.
56 MANUAL OF OCULAR PATHOLOGY

Intraocular tumors often pose a diagnostic problem for the general

ophthalmologist due to its rarity. Some of these tumors, e.g. retinoblastoma,
malignant melanoma of the choroid, etc. have the potential to cause death
due to metastasis. The pathologist provides guidelines for further management
and prognosis and improves the understanding of these tumors by
clinicopathologic correlations.

RETINOBLASTOMA
Retinoblastoma is the most common pediatric intraocular malignancy. It is
the third most common intraocular malignancy in any age group.
The tumor is unique as it exists in both familial and nonfamilial forms.
It is also one of the highly malignant tumors of the eye.
- It occurs in 1 in 14,000-34,000 live births. The tumor is seen commonly
below 3 years of age and presents clinically as a white reflex in the pupil,
squint, spontaneous hyphema, pseudohypopyon (tumor seeding of anterior
chamber) and proptosis (advanced stage).
- Complete spontaneous regression is also possible. Enucleation is the
treatment of choice in advanced stages of retinoblastoma.
- Enucleated eyes are subjected to histopathological study for confirmation
of the clinical diagnosis and to rule out tumor cell invasion at the surgical
margin of the optic nerve.

Gross Examination
On sectioning, the retinoblastoma shows several characteristic findings.

Findings
1. Chalky white mass, often friable (Figure 7.5A).
2. Can present with different growth patterns exophytic, endophytic, mixed
and diffuse.
3. Extension to the uvea, epibulbar structures and optic nerve is grossly visible
in advanced cases.
4. Choroidal invasion may also be grossly visible (Figure 7.1).

MICROSCOPIC EXAMINATION
Findings
Low Power
- Basophilic mass (e.g.) with lightly eosinophilic areas (necrosis of tumor).
- Multiple dense basophilic foci (calcification).
- Tumor can be endophytic, exophytic, mixed (endophytic and exophytic)
or diffuse infiltrating (Figures 7.2 to 7.4).
 INTRAOCULAR TUMORS 57

Figure 7.1: Cut section of the globe showing gross choroidal

invasion in a case of retinoblastoma

Figures 7.2: Showing different growth patterns in retinoblastoma; A Endophytic,

B: Exophytic, C: Diffuse infiltrating

Figures 7.3A and B: Showing tumor arising from the inner layer of the retina
58 MANUAL OF OCULAR PATHOLOGY

Figures 7.4A and B: Showing tumor arising from the outer layer of the retina (arrow)

High Power
Tumors show two different types of cellular characteristics (Figures 7.5A
and B):
a. Poorly differentiated
b. Well-differentiated.

Figures 7.5A and B: A. Cut section of the globe in retinoblastoma showing a chalky white
mass filling whole of the vitreous cavity; B. Microphotograph showing basophilic tumor mass
in a case of retinoblastoma

a. Poorly Differentiated
- Small to medium sized round cells with hyperchromatic nuclei and
scanty cytoplasm (Figure 7.6).

Figure 7.6: Showing undifferentiated retinoblastoma cells with hyperchromatic

nuclei and scanty cytoplasm (arrow)
 INTRAOCULAR TUMORS 59
b. Well-differentiated
a. Rosettes
b. Fleurettes.

a. Rosettes
Rosettes are of two types:
i. Homer-Wright
ii. Flexner-Wintersteiner.

i. Homer-Wright Rosettes (Figure 7.7A)

- Not specific for retinoblastoma.
- Can be seen in neuroblastoma and medulloepithelioma.
- Tumor cells are arranged radially around a central core of neural fibers
in contrast to the clear lumen in Flexner-Wintersteiner type.

ii. Flexner-Wintersteiner Rosettes (Figure 7.7B)

- Highly specific for retinoblastoma.
- Cuboidal cells arranged around a clear central lumen.

Figures 7.7A and B: A. Homer-Wright rosettes—Tumor cells are arranged radially around a
central core of neural fibrilin in contrast to the clear lumen in Flexner-Wintersteiner type; B.
Photomicrograph showing Flexner–Wintersteiner rosettes consisting of tumor cells arranged
around a central lumen

b. Fleurettes
- Highly specific for retinoblastoma.
- Flower boquet like aggregates of tumor cells with bulbous eosinophilic
processes projecting through the fenestrated membrane (Figure 7.8).

Other Pathologic Features

- Areas of necrosis and calcification.
- Endothelial hyperplasia around blood vessels within the tumor.
- DNA clumping around blood vessels within the tumor.
- Neovascularization of the iris.
60 MANUAL OF OCULAR PATHOLOGY

Figure 7.8: Showing “Fleurettes” which are flower bouquet like aggregates of tumor cells
with bulbous eosinophilic processes projecting through the fenestrated membrane

- Extension of tumor cells into the anterior chamber, iris, choroid, optic nerve
and orbital tissue (Figs 7.9 A and B).

Figures 7.9A and B: Cross section of the optic nerve showing invasion of retinoblastoma
into the optic nerve

Histopathologic Risk Factors and their Associations with Prognosis

Histopathologic risk factors for prognosis include tumor invasion into the
optic nerve, massive choroidal invasion and orbital involvement.
5 year mortality rate is given below based on extent of tumor spread into
optic nerve, choroid and orbit.
A. Optic nerve Mortality rate
- Not involved 8%
- Upto lamina cribrosa 15%
- Beyond lamina cribrosa 44%
- Surgical end of transection 65%
B. Choroidal invasion 25%
C. Orbital invasion 91%

Malignant Melanoma of the Choroid

- Malignant melanoma of the choroid is the most common primary
intraocular tumor in adults in USA.
 INTRAOCULAR TUMORS 61
- The tumor is relatively uncommon in the pigmented population.
Incidence
- 6 cases/1,000,000 in USA.
- Surveys from countries other than USA, e.g. Finland, Denmark, Norway,
Alberta (Canada) showed a similar rate.
There are only a few series reported in Indian literature. In a series by a
major eye institute in India, 103 patients underwent enucleation for the
diagnosis of malignant melanoma of choroid between 1987 to 2001. (Ind J
Ophthalmol 2004; 52: 41-44).
Age
- The disease is found most often in the sixth decade
- Very rare below 20 years.
- Median age at diagnosis is about 55 years.

Pathology
- The tumor can arise from choroid, ciliary body or both (Figure 7.10C).
- Ciliary body tumors have a poorer prognosis.
Pigmentation
- Variable pigment content (amelanotic to deeply pigmented) and multiple
variably pigmented clones are often seen.

Growth Pattern
This is of two types: (i) Focal, (ii) Diffuse.

i. Focal
- Common.
- Early tumors confined to the uvea.
- Oval in shape.
- As the tumor grows, it can rupture through the Bruch’s membrane and
produce a collar button or mushroom-shaped mass (Figures 7.10A and B).

Figures 7.10A to C: A. Fundus photograph showing a pigmented mass breaking through Bruch’s
membrane in a case of malignant melanoma of the choroid; B. Showing gross photograph of
the malignant melanoma of the choroid with mushroom-shaped pigmented tumor mass; C.
Showing low power photograph showing collar stud appearance of a case of malignant melanoma
of the choroid rupturing through Bruch’s membrane
62 MANUAL OF OCULAR PATHOLOGY

ii. Diffuse
- Rare.
- Involves a larger area of the uvea.
- Known to be more aggressive, resulting frequently in extrascleral extension.
- Associated with secondary retinal detachment commonly.
- Macrophages laden with lipofuscin pigments correspond with the orange
pigmentation seen clinically.
Histologic characteristics of uveal melanoma cells (Tables 7.1 and 7.2):
Five histologic types of uveal melanoma cells are recognized and are used
for the classification of melanomas of the uveal tract (Callender’s cytologic
classification).
Table 7.1: Cell type
Cell Type Approximate no. of choroidal melanomas (%)
Spindle A 5
Spindle B 39
Epithelioid 3
Mixed 45
Necrotic 8

Table 7.2: Characteristic histologic features

Cell type Shape Cytoplasm Nucleus Nucleolus Cohesiveness
Spindle A Spindle Scanty Long and narrow Poorly defined Cohesive
Spindle B Spindle Less Oval and round Well-defined Cohesive
Epithelioid Polygonal Abundant Oval and round > Spindle B Loosely
cohesive

New AFIP Classification

1. Spindle cell nevi (spindle A exclusively).
2. Spindle cell malignant melanoma (mixture of spindle A and spindle B—
Figure 7.11A).
3. Mixed cell melanoma (mixture of spindle and epithelioid cells).
4. Epithelioid cell melanoma (Figure 7.11B).

Figure 7.11A: Spindle cell melanoma

 INTRAOCULAR TUMORS 63

Figure 7.11B: Epithelioid cell melanoma

Different cell types correlate with the mortality of the patient and are given
in Table 7.3:
Table 7.3: Cell type and mortality
Tumor Cell type and mortality 5-year mortality
Spindle A Predominantly spindle A 5
Spindle B Predominantly spindle B 14
Mixed Spindle B and epithelioid 51
Epithelioid Predominantly epithelioid 69
Necrotic Majority of cells are necrosed 51

Other Histologic Features Related to Prognosis

1. Larger size More than 1.0 cm3 – poor prognosis.
2. Invasion of tumor Scleral canal
Scleral tissue
Optic nerve
Vortex vein
Extraocular extension.

Size of the Tumor vs Prognosis

Size 5 year mortality rate
< 11 mm 5-47%
11-15 mm 13-44%
> 15 mm 23-73%
64 MANUAL OF OCULAR PATHOLOGY
Table 7.4: Survival prognostic factors in uveal melanoma
S. Category Expressions Factor Outcome
No.
1 Clinical i. Locations Iris Good
ii. Configuration Choroidal Intermediate
Ciliary Poor
Diffuse Poor
2 Histopathologic i. Cell type Spindle Good
ii. Mitotic activity Mixed Intermediate
iii. Vascular network Epithelioid Poor
iv. TIL Low Good
v. EOE Medium Intermediate
High Poor
Absent Good
Present Poor
Low Good
High Poor
Absent Good
Present Poor
3 Cell proliferation i. AgNOR count Low Good
ii. Aneuploidy DNA index High Poor
iii. Ki-67 expression Low Good
iv. PCNA expression High Poor
Low Good
High Poor
Low Good
High Poor
4 Histocompatibi- HLA – A expression Low Good
lity antigens High Poor
5 Cytogenetic Monosomy 3 and duplication 8q Absent Good
Present Poor
6 Molecular genetic i. c-myc expression High Good
ii. Cyclin D1, p53, MDM2 Low Poor
expression Positivity Poor
iii. MMP 2 and MMP 9 Negativity Good
iv. IGF–IR Positivity Poor
Negativity Good
Low Good
high Poor

Abbreviations: AgNOR, nucleolar organizer regions identified by silver staining

EOE: Extrascleral extension
IGF-IR: Insulin like growth factor-1 receptor
MMP: Matrix metalloproteinase
PCNA: Proliferating cell nuclear antigen
TIL: Tumor infiltrating lymphocytes
(Courtesy: Ophthalmology clinics of North America, March 2005, volume 18, number 1)

Extension of Melanoma
1. Vortex veins
2. Scleral emissary canals
3. Vitreous infiltration
4. Optic nerve and orbital invasion—more in peripapillary melanoma.
5. Melanomalytic glaucoma—macrophages with engulfed melanin pigment
blocking the angle.
 INTRAOCULAR TUMORS 65
Novel Prognostic Parameters in Uveal Melanoma
Uveal melanoma is the most common primary cancer of the eye and the second
most common form of melanoma. Uveal melanoma has a strong predilection
for hematogenous metastasis, particularly to the liver. Several prognostic
factors based on clinical and histological features were identified but none
of these prognostic factors were specific enough for identification of patients
at risk for metastatic disease (Table 7.4). Chromosomal aberrations were
studied by cytogenetic analysis, spectral karyotyping and fluorescent insitu
hybridization.

Chromosome in situ hybridization and microsatellite analysis: Monosomy 3 was

found to be an early and determinant event in tumor progression.
Chromosome in situ hybridization avoids the requirement for fresh tissue
and the potential examination of nonrepresentative tumor populations or
nontumour DNA, and different regions within a tumor, with different cell
types may be analyzed. Intra tumor heterogeneity for monosomy 3 was
observed, hence these limitations paved the way for gene expression studies
where two distinct molecular subgroups were identified—Class I expression
signature had low risk and Class II had high risk for metastasis.
A strong correlation between Class II and monosomy 3 was found.
MicroRNA expression studies based on similar subtypes of gene expression
identified MicroRNAs upregulated in Class II. Identifying specific interaction
between deregulated MicroRNAs and discriminating mRNA expression will
provide better insight into identifying miRNAs in tumor progression and lead
to new avenues in molecular therapy-based research.

Malignant Melanomas of Iris

- Constitutes 5 to 8% of all melanomas of the uveal tract.
- Most common primary neoplasm of the iris.
- It usually arises from the anterior border near the pupillary margin.
- Growth patterns:
• Nodular
• Diffuse
• Tapioca, i.e. multiple nodules project from the surface of iris.

Microscopic Features
- Most iris melanomas are of the spindle cell type.
- Slow growing and relatively benign.
- Better prognosis.
66 MANUAL OF OCULAR PATHOLOGY

Melanomas of Ciliary Body

Accounts for 9% of all uveal melanomas, the histopathological findings,
cytological classification and prognostic factors of ciliary body melanoma is
similar to choroidal melanoma.

Metastatic Tumors
Metastatic tumors are rare intraocular malignancies encountered in
ophthalmic practice. It has been found that 10% of the patients who die of
cancer have intraocular metastasis.

Primary Site of Choroidal Metastasis in Order of Frequency

Male Female
1. Lungs 1. Breast (Figure 7.12)
2. Unknown primary 2. Lungs
3. Skin melanoma 3. Unknown primary
4. Kidney 4. Gastrointestinal and pancreas
5. Gastrointestinal and pancreas 5. Skin melanoma
6. Prostate 6. Other rare sources
7. Other rare sources

Figure 7.12: Showing metastasis in the choroid from breast carcinoma

Medulloepithelioma
It is also known as “Diktyoma”. They originate from nonpigmented ciliary
epithelium. Most common in children around 5 years of age.

Histopathology
It can be benign or malignant which are further subclassified into teratoid
or nonteratoid medulloepithelioma (Figure 7.13).
 INTRAOCULAR TUMORS 67

Figure 7.13: Photomicrograph showing neuroepithelial elements

in a case of medulloepithelioma

Benign
a. Nonteratoid—Contains multilayered sheets and cords of neuroepithelial cells
similar to that of ciliary epithelium.
b. Teratoid—It also contains heteroplastic tissue-like hyaline cartilage or
rhabdomyoblasts.

Malignant
a. Nonteratoid—Tumor consists of poorly differentiated neuroepithelial cells
with areas resembling retinoblastoma. However, the lumen of the rosettes
is surrounded by more than a single layer of cells.
b. Teratoid—Shows areas of undifferentiated cartilaginous tissue and
rhabdomyoblasts with carcinomatous or sarcomatous change.

Intraocular Lymphoma
Primary lymphoma: Large B-cell Non-Hodgkin’s lymphoma, previously known
as reticulum cell sarcoma, often presenting clinically as an intermediate uveitis
with or without involvement of the retina, retinal pigment epithelium and
choroid. On clinical evaluation, cellular infiltration of the vitreous may suggest
an inflammatory process. In most cases a vitreous biopsy alone is adequate
for diagnosis; sometimes, however, a more aggressive approach, with
choroidal or retinal biopsy, may be required. Vitreous biopsy of this lymphoma
generally reveals large pleomorphic cells wih prominent round or oval nuclei
and scanty cytoplasm. The nuclear membrane may show indentations. Often
one or more prominent nucleoli are present. Necrotic or ‘ghost’ cells often
serve as a marker for this tumor (Figures 7.14A to C)
However, interpretation of the vitreous biopsy may still be difficult due
to the presence of a number of inflammatory cells. The cytologic picture and
the presence of ghost or necrotic cells may help in this differentiation. A
monomorphic population of normal-appearing lymphocytes does not rule
68 MANUAL OF OCULAR PATHOLOGY

out the diagnosis of lymphoma. In such situations, identification of a

monoclonality of the B cells by immunostaining, (kappa and lambda chains)
may further suggest lymphoma.

Figures 7.14A and B: A. Montage photograph showing multifocal creamy yellow subretinal
plaque lesion in a patient; B. Magnetic resonance image showing lesion in the brain in a case
of intraocular lymphoma (arrow)

Figure 7.14C: Microphotograph showing lymphoma cells in a case of intraocular

lymphoma (inset showing higher magnification of typical lymphoma cells)
70 MANUAL OF OCULAR PATHOLOGY

The retina is the neural layer which lines the inner eye and it is composed
of ten layers from outside inwards (Figure 8.1).

Figure 8.1: Normal retina

Layers of Retina
1. Retinal pigment epithelium
2. Photoreceptor layer (layer of rods and cones)
3. External limiting membrane
4. Outer nuclear layer
5. Outer plexiform layer
6. Inner nuclear layer
7. Inner plexiform layer
8. Ganglion cell layer
9. Nerve fiber layer
10. Internal limiting membrane.

Diabetic Retinopathy
- Diabetic retinopathy is one of the major worldwide causes of blindness
in adults.
- Clinically diabetic retinopathy is divided into two stages:
1. Nonproliferative or background diabetic retinopathy.
2. Proliferative diabetic retinopathy.
Pathologically however, changes can be divided into four stages:
1. Preretinopathy
2. Nonproliferative
3. Preproliferative
4. Proliferative.
The following basic pathological changes are seen in diabetic retinopathy:
a. Breakdown of blood-retinal barrier
b. Capillary basement membrane thickening.
 DISEASES OF THE RETINA 71
c. Loss of microvascular intramural pericytes
d. Microaneurysms
e. Capillary acellularity.

Preretinopathy
A. Breakdown of blood-retinal barrier
B. Increase in retinal blood flow
C. Impaired autoregulation of retinal vasculature.

Site of Damage
Intercellular tight junction is the primary site.
Leakage occurs from:
- Retinal vessels.
- Choriocapillaries with malfunctioning RPE.
- Both.

Nonproliferative Retinopathy
I. Vascular changes
II. Exudative changes
III. Hemorrhagic changes.
The earliest histological change is the selective loss of intramural pericytes
in retinal capillaries.

I. Vascular Changes
1. Loss of capillary pericytes.
Pericyte/endothelial cell ratio.
Normal 1:1
Diabetic retinopathy <1:1
2. Capillary microaneurysms: Pathologically, these microaneurysms can be
seen in retinal digest preparations as grape-like or spindle-shaped
dilatations of the retinal capillaries.
3. Thickening of capillary basement membrane: Thickening of the microvascular
basement membrane has been observed in retinal capillaries and
choriocapillaries (diabetic choroidopathy).
4. Capillary acellularity: With the advancement of microvascular lesion in
diabetic retinopathy, there occurs complete loss of all cellular elements
from retinal micorvessels.

II. Exudative Changes

The following exudative changes are seen:
Clinical Histopathology
a. Hard exudates Serum and glial neuronal breakdown products in
outer plexiform layer (Figures 8.2A and B).
72 MANUAL OF OCULAR PATHOLOGY

Figures 8.2A and B: A. Clinical photographs of the patient with hard exudates;
B. Showing serum and glial neuronal breakdown products in outer plexiform layer (arrow)

b. Soft exudates Swollen ends of ruptured axons in nerve-fiber layer

(Cotton wool (Figures 8.3A and B).
spots)

Figures 8.3A and B: A. Clinical photographs of the patient with soft exudates; B. Showing
eosinophilic acellular globular deposits in the nerve fiber layer of the retina in a case of soft
exudates (arrow)

III. Hemorrhagic Changes

Following changes are seen:

Clinical Histopathology
Dot and blot hemorrhages Hemorrhages in inner nuclear layer and
outer plexiform layer.
Flame-shaped hemorrhages Small hemorrhages in nerve fiber layer.
Globular hemorrhages Hemorrhages in middle retinal layers.
Confluent hemorrhages Hemorrhages in all retinal layers.
Preretinal hemorrhages Hemorrhages just below the internal
limiting membrane.

Preproliferative Diabetic Retinopathy

1. Increase in cotton wool spots
2. Venous dilatations
3. Venous beading.
 DISEASES OF THE RETINA 73
Proliferative Diabetic Retinopathy

Clinical Histopathology
1. Retinal neovascularization (NVE) New vessels proliferate in front of the
retina and optic nerve. They usually
emanate from the venous circulation,
after breaking through the internal
limiting membrane of the retina.
2. Optic disk neovascularization New vessels arise from the optic head.
(NVD)

Diabetic Maculopathy
Clinical Histopathology
Edema in the macular region Multiple cystoid spaces in the outer plexiform
and inner layer of retina in the macular region,
probably containing extracellular fluid.
76 MANUAL OF OCULAR PATHOLOGY

Coats’ disease is an idiopathic condition characterized by retinal vascular

exudation, telangiectatic retinal vessels and exudative retinal detachment. The
disease was first described by Coats in 1908. Coats’ disease affects predominantly
male and is usually unilateral. The average age at diagnosis is between 8 to
16 years. Coats’ disease can also be diagnosed in adulthood. Usually children
present with dimness of vision, leukokoria (Figure 9.1A) or strabismus. Severe
juvenile forms of Coats’ disease often mimick retinoblastoma and the eye is
often enucleated with the suspicion of retinoblastoma.
Histopathology of the enucleated globe reveals often exudative retinal
detachment (Figure 9.1B), retinal edema and cystic degeneration of the retina
(Figure 9.2B). Telangiectatic retinal vessels can be seen (Figure 9.3). Lipid-
laden macrophages can be seen beneath and in the outer layers of the retina.
Cholesterol clefts can be seen within the eosinophilic exudates (Figure 9.2A).

Figures 9.1A and B: A. Slit lamp photograph showing leukokoria in a case of Coats’
disease; B. Low power microphotograph showing bullous exudative retinal detachment

Figures 9.2A and B: A. Showing multiple cholesterol clefts in the eosinophilic exudates;
B. Showing extensive retinal edema with cystic spaces within the retinal layers

Figure 9.3: Showing telangiectatic retinal vessel in a case of Coats’ disease

78 MANUAL OF OCULAR PATHOLOGY

The vitreous is a transparent jelly like structure situated behind the lens and
surrounded by the inner surface of the retina, ciliary body and optic nerve
head. It is about 4ml in volume and weighs about 4 gm. Its index of refraction
is equal to that of the aqueous. It transmits light to the retina. It assists in
supporting surrounding structures in maintaining intraocular pressure and
the contour of the eye.
The attachment of the vitreous to adjacent structures varies in firmness.
It is strongest at the vitreous base and at the margin of the optic disk. The
vitreous base straddles the ora serrata as a circular band varying in width
from 2 to 6 mm. The vitreous is loosely attached to the macular region over
a zone of 3 to 4 mm in diameter.
The vitreous gel is composed of a liquid phase and a solid phase. The solid
component of the vitreous constitutes only 1% of its weight. These include
collagen fibrils, hyalocytes and fibroblasts, and minute amount of protein.
The liquid phase is 99% water with some inorganic salts, sugar, ascorbic acid,
soluble proteins and hyaluronic acid.
Light microscopic study of fixed and stained vitreous shows a series of
net-like fibrous membrane extending centrally from the vitreous base and
parallel to the retina. Vitreous collagen is predominantly type II collagen.
Vitreous is intimately attached in the young adults. This attachment
weakens with increasing age. Vitreous may get separated from the retina in
adults (posterior vitreous detachment). The space between the detached
vitreous and the retina is filled up with nonviscous fluid (liquefied vitreous).

ASTEROID HYALOSIS
It is usually found in more elderly patients and is unilateral in 75% of these
cases. This is a benign degenerative process occurring in the vitreous which
is otherwise normal. Clinically, multiple minute, spherical or disk-shaped
opacities are seen in the vitreous. They have a glistening polychromatic
appearance (Figure 10.1A). Microscopically they are spherical, 0.01 to 0.1 mm
in diameter and are weakly basophilic in hematoxylin and eosin stain. They
are stained by lipid stains like oil red O or Sudan black. They stain intensely
positive blue with stains for acid mucopolysaccharide like alcian blue or
colloidal iron (Figure 10.1B). This stain reaction is not affected by
hyaluronidase.

VITREOUS AMYLOIDOSIS
Bilateral amyloid deposition may occur in the retina and vitreous either as
a part of a primary systemic heredofamilial process or in individuals. with
primary systemic nonfamilial amyloidosis. It may also occur without systemic
or familial involvement as reported by us.
 DISEASES OF THE VITREOUS 79

Figures 10.1A and B: A. Showing fundus photograph of a patient with multiple round opacities
in the vitreous of a case of asteroid hyalosis; B. Showing multiple globular bodies stained positive
with alcian blue in a vitrectomy specimen from asteroid hyalosis

Fundus examination shows numerous strand-like opacities in the anterior

vitreous and posterior pole (Figure 10.2A). The vitrectomy specimen on
hematoxylin and eosin stain shows homogenous acellular eosinophilic
material that stain positive with Periodic Acid–Schiff and Congo red stain
(Figure 10.2B). Yellowish green birefringence and dichroism is seen with the
Congo red stain when viewed under polarized light. Electron microscopy
shows fine fibrils of 9 to 12 nm in diameter arranged irregularly
with an intervening space of about 3 nm.

Figures 10.2A and B: A. Showing fundus photograph of a case of vitreous amyloidosis showing
multiple vitreous strands; B. Showing positive Congo red stain in vitrectomy specimen of vitreous
amyloidosis
82 MANUAL OF OCULAR PATHOLOGY

The study of the orbit is a treatise of soft tissue pathology.

DIFFERENT TISSUES WITHIN THE ORBIT

1. Eye and optic nerve
2. Adipose tissue
3. Elastic and fibrous connective tissue
4. Blood vessels and nerves
5. Skeletal and smooth muscles
6. Cartilage, Bone
7. Lacrimal gland.

CLASSIFICATION (TABLE 11.1)

Table 11.1: Classification of space-occupying lesions in the orbit

Cystic lesions 30%

Lacrimal gland lesions 13%
Inflammatory lesions simulating tumors 13%
Secondary orbital tumors 11%
Lymphoid tumors 10%
Vasculogenic lesions 6%
Others 17%
Total 100%

ORBITAL INFLAMMATION
Orbital inflammatory diseases and ‘pseudotumors’ are more common than
neoplasms.

A. Acute
a. Suppurative
b. Non-suppurative.

B. Chronic
a. Granulomatous
b. Nongranulomatous.

Orbital Cellulites
- Usually invades from sinuses
- Orbital inflammation.
 PATHOLOGY OF THE ORBIT 83
Causes
1. Fungi
- Aspergillus
- Mucormycosis
i. Debilitated patients.
ii. Cancer, diabetic ketoacidosis, patient on immunosuppressive
treatment.
iii. Large, nonseptate fungus visible on H&E stain.
2. Bacteria – pyogenic.
3. Tuberculosis – chronic granulomatous inflammation.
4. Parasites – hydatid cyst.
5. Sarcoidosis.
6. Vasculitis.
- Wegener’s granulomatosis.
- Polyarteritis nodosa.
7. Immunogenic – thyroid ophthalmopathy.
8. Idiopathic – pseudotumor.

PSEUDOTUMOR
Microscopic Examination
A. Polymorphs, lymphocytes, plasma cells, lymphoid follicles, eosinophils:
- Infiltration of orbital fat, muscle, tendon.
- Heals by progressive fibrosis.
B. Reactive lymphoid hyperplasia:
- Mature lymphocytic infiltrate.
- Look for lymphoid follicle, plasma cells, etc.
- Immunohistochemistry to differentiate from lymphoma.
- Lymphoma – monoclonal.
- Reactive lymphoid hyperplasia – polyclonal.

THYROID OPHTHALMOPATHY
Microscopic Examination
- Orbital tissue edema.
- Lymphocytic infiltration.
- Increase in mucin.
- Fibrosis, degeneration and inflammation of extraocular muscles.
- Optic atrophy, corneal changes in late stages.

Vasculitis
- Polyarteritis.
- Temporal arteritis.
84 MANUAL OF OCULAR PATHOLOGY

- Wegener’s granulomatosis:
 Generalized
 Limited.

Wegener’s Granulomatosis
- Necrotizing vasculitis of upper respiratory tract, lungs and kidney
- Limited form – no renal involvement
- Ocular involvement (28.5%)
- Proptosis 40%
- Scleritis 25%
- Peripheral corneal ulcer.
Micro: Granulomatous vasculitis with fibrinoid necrosis.

Orbital Tumors
- Primary
- Secondary from adjacent structures
- Metastatic.

Primary Orbital Tumors

1. Choristomas
2. Hamartomas
3. Vasculogenic tumors
4. Neurogenic tumors.
a. Peripheral nerve – schwannoma, neurofibroma
b. Optic nerve – optic nerve glioma.
5. Epithelial tumors of lacrimal gland
6. Lymphoid tumors and leukemias
7. Osseous and fibro-osseous tumors
8. Cartilaginous tumors
9. Rhabdomyoma and rhabdomyosarcoma
10. Lipocytic and mixoid tumors
11. Primary melanocytic tumors.

Congenital Tumors
- Choristoma
- Hamartoma.

Choristoma
Congenital tumors composed of tissues which are not normally found in the
area.
 PATHOLOGY OF THE ORBIT 85
4 types have been described:
- Dermoid
- Epidermoid
- Teratoma
- Ectopic lacrimal gland.

Dermoid
Site—Upper and outer aspect of orbit
Gross—Usually solid, occasionally cystic
Micro—The cyst is lined by keratinized stratified squamous epithelium and
the cyst wall contains epidermal appendages (sweat glands, hair follicles,
sebaceous glands). The lumen contains keratin or hair.

Epidermal Cyst
The cyst wall is lined by keratinized stratified squamous epithelium, but the
cyst wall does not bear adnexal structures.

Hamartoma
It is a congenital benign tumor composed of hypertrophy and hyperplasia
of mature tissue at a normal location.

Types
- Phakomatosis
- Hemangioma
- Lymphangioma
- Hemangiopericytoma.

Vasculogenic Tumors
1. Cavernous hemangioma
2. Capillary hemangioma
3. Hemangiopericytoma
4. Lymphangioma
5. Kaposi’s sarcoma.

Cavernous Hemangioma
- Most common adult vascular tumor
- Common in middle aged females
- Low grade proptosis.
Gross: Round encapsulated vascular lesion (Figure 11.1A).
86 MANUAL OF OCULAR PATHOLOGY

Micro: They are composed of large, dilated blood cells (Figure 11.1B). The
stroma contains fibroblasts, smooth muscle and fat and may show hyaline
or myxoid changes.

Figures 11.1A and B: A. Gross photograph showing an encapsulated hemorrhagic mass in

a case of Cavernous hemangioma; B. Histologic section showing large blood filled spaces
separated by thick septa

Capillary Hemangioma
- Infants
- Smaller in size
- Solitary
- Proptosis within 1-2 weeks of birth.

Micro
- Composed predominantly of capillaries
- Lined by benign plump endothelial cells.

Hemangiopericytoma
- Common in adults
- Manifests with proptosis, pain and diplopia.

Micro
- Densely packed oval to spindle-shaped cells with Staghorn vascular pattern
(branching vascular pattern).
- Reticulin stain is helpful in demonstrating tumor cells.

Lymphangioma
- Common in children.
- Characteristically there is fluctuation in proptosis.

Gross
- Uncapsulated lesion.

Micro
- Lymphatic vascular spaces
- Well-formed lymphoid aggregates in fibrotic interstitium.
 PATHOLOGY OF THE ORBIT 87
Peripheral Nerve Tumors
Neurofibroma
- Solitary
- Plexiform.
Neurilemmoma (Schwannoma)
- Encapsulated round tumor.
- Usually benign but may also be malignant.
- Composed of proliferating Schwannoma cells in a collagen matrix arranged
in two histologic patterns (Figure 11.2).

Figure 11.2: Showing hypocellular and hypercellular areas in a case of Schwannoma

i. Antoni A
ii. Antoni B.

Antoni A pattern: Hypercellular area made up of interlacing spindle-shaped

cells and often contains cellular configurations resembling sensory corpuscles
(Verocay bodies).
Antoni B pattern: Hypocellular area made up of spindle-shaped cells in loose-
mucoid stroma. Vessels are thick-walled and show hyalinization.

Optic Nerve and Meningeal Tumors

- Meningioma
- Juvenile pilocytic astrocytoma (optic nerve glioma).

Optic Nerve Glioma

- 2-6 years
- 90% before the age of 20
- Female > male
- Associated with neurofibromatosis (10-50%).
- Unilateral visual loss and axial proptosis (Figure 11.3A).
88 MANUAL OF OCULAR PATHOLOGY

Micro
- Fusiform swelling of nerve
- Proliferation of benign spindle-shaped pilocytic astrocytes (Figure 11.3B)
- Eosinophilic clump of glial filaments
- Mucinous degeneration.

Optic Nerve Meningioma

- Benign tumor arising from meningothelial cells of meninges
- Severe visual loss with minimal proptosis
- Optociliary shunts are often present.

Figures 11.3A and B: A. Patient with optic nerve glioma; B. Showing elongated tumor cells
to resemble hair (Pilocytic) along with degenerative eosinophilic substance (Rosenthal fibers)
(arrow)

Types
• Primary Arises from optic nerve meninges
• Secondary Invades from orbit
• Ectopic From ectopic nests.

Micro
- Clusters and whorls of meningothelial cells.
- Intranuclear vacuoles of herniated cytoplasm.
- Psammoma bodies (Figure 11.4).

Rhabdomyosarcoma
- Most common malignant orbital tumor in childhood
- Average age – 7 years.
- Fulminant and rapidly develops proptosis
- Superior orbit most commonly involved.
 PATHOLOGY OF THE ORBIT 89

Figure 11.4: Optic nerve sheath meningioma: Whorls of meningothelial cells

along with a psammoma body is seen

Micro
It is of 4 types:
- Embryonal
- Botryoid
- Alveolar
- Pleomorphic.

Embryonal
- Most common
- Fasicles of tumor cells
- Loose myxomatous stroma
- Spindle cells and strap cells
- Cross-striations.

Botryoid
Embryonal type present beneath the mucous membrane.

Alveolar
- Worst prognosis
- Large polygonal cells with abundant eosinophilic cytoplasm
- Loosely cohesive cells enclosed by connective tissue trabeculae.

Pleomorphic
- Rarest
- Older patients
- Striated muscle differentiation
90 MANUAL OF OCULAR PATHOLOGY

- Cross-striation.
- Strap cells with abundant eosinophilic cytoplasm.

Treatment
- Radiotherapy and chemotherapy (70% survival)
- Exenteration (40% survival).

Malignant Lymphoma
- Malignant lymphoma of the orbit may be primary or orbital manifestation
of systemic lymphoma. Hodgkin lymphoma is rare in the orbit and the
majority of primary orbital lymphomas are non-Hodgkin’s lymphoma
which are immunophenotypically B cell type.
- Clinical:
• Usually older patients except Burkitt’s lymphoma which is more
common in children.
• Proptosis or upper lid ptosis.
- Microscopic examination:
• Low-grade lymphomas—Revised European American Lymphoma (REAL)
classification includes marginal zone lymphomas, chronic lymphocytic
lymphoma/small lymphocytic lymphoma, follicular lymphomas.
• High-grade lymphomas—Large cell lymphoma, lymphoblastic, Burkitt’s
lymphoma.

Marginal Zone Lymphoma

- Shows poorly formed follicles with heterologous cells comprising of
lymphocytes, plasma cells and eosinophils. These are B cell type and CD
5 and CD 10 – Negative.

Small Lymphocytic Lymphoma

This is composed of a diffuse homogenous sheet of mature appearing
lymphocytes.

Follicular Lymphoma
Follicles are well-formed and dominated by cleaved (centrocytes) and few
non-cleaved cells (centroblasts).

Burkitt’s Lymphoma
- Endemic type—Common in children in equator Africa.
- Sporadic type—Common in young adults and older and is present
worldwide.
 PATHOLOGY OF THE ORBIT 91
Microscopic Examination
A diffuse population of monomorphic lymphoid cells, interspersed with
tingible body macrophages is a characteristic feature (Starry sky pattern).
Large Cell Lymphoma
- Large cells with vesicular nuclei and distinct nucleoli with numerous mitotic
figures.
Tumors of the Lacrimal Gland
A. Epithelial tumors.
B. Non-epithelial tumors.
- Lymphoma
- Lymphoid hyperplasia
- Inflammation
- Inflammatory pseudotumor.
A. Epithelial Tumors
- Benign mixed tumour
- Malignant mixed tumour
- Adenoid cystic carcinoma
- Ductal adenocarcinoma
- Miscellaneous, e.g. mucoepidermoid.
Epithelial Lacrimal Gland Tumors
a. Benign mixed tumor (Pleomorphic adenoma) –50%
Most common epithelial tumor.
Gross: Encapsulated and expansile
Micro:
- Mixture of epithelial and mesenchymal elements (Figure 11.5).
- Double layer of epithelial cells (epithelial ductules)
- Stroma may appear myxoid

Figure 11.5: Pleomorphic adenoma of the lacrimal gland showing epithelial cells as well
as mesenchymal component
92 MANUAL OF OCULAR PATHOLOGY

- Good prognosis.
b. Malignant mixed-13%
- Malignant transformation of benign mixed tumor
- Poor prognosis.
c. Adenoid cystic- 25-30%
- 2nd most common epithelial tumor of the lacrimal gland
- Pain is a common symptom and occurs due to perineural invasion
- Tightly packed, benign appearing basal cells are found arranged in
masses of variable sizes.

There are five types seen on microscopy:

a. Cribriform (Swiss-Cheese pattern)—due to cystic spaces with tumor cell
aggregates (Figures 11.6A and B)
b. Basaloid (Solid)
c. Sclerosing
d. Comedo
e. Tubular.
Presence of basaloid pattern has been associated with a poorer prognosis
than in its absence.

Figures 11.6A and B: A. Adenoid cystic carcinoma of the lacrimal gland showing cystic spaces
within aggregates of basaloid tumor cells giving rise to “Swiss-Cheese” pattern; B. Showing
typical perineural invasion in a case of adenoid cystic carcinoma

Orbital Metastasis
Tumors from distant sites spreading to the orbit by metastasis.

Common Primary Sites

- Female – Breast
- Male – Prostate
- Immunohistochemistry using specific markers, e.g. estrogen receptors for
breast and prostatic acid phosphatase for prostate can indicate the primary
site.
 PATHOLOGY OF THE ORBIT 93
Secondary Orbital Tumors
Primary tumors from the adjacent site extending to the orbit:
a. Globe:
- Melanoma and ciliary epithelium carcinoma
- Retinoblastoma.
b. Conjunctiva:
- Squamous cell carcinoma
- Melanoma
- Mucoepidermoid carcinoma.
c. Lid:
- Squamous cell carcinoma
- Basal cell carcinoma
- Sebaceous gland carcinoma.
d. Others, e.g. sinuses, nasopharynx, intracranial.
96 MANUAL OF OCULAR PATHOLOGY

Cytology is often a reliable and valuable aid in diagnosis of various ocular

diseases. Its noninvasiveness, simplicity and cost-effective nature makes it
an invaluable investigation.
Various methods used to obtain representative sample for cytology of eye
are:
I. Imprint smear (Impression cytology)
II. Conjunctival or corneal scraping
III. Aqueous tap
IV. Vitreous tap
V. Fine needle aspiration biopsy.

I. IMPRESSION CYTOLOGY
It is a noninvasive technique for obtaining a representative sample of
superficial epithelial cells from the ocular surface.

Indications
• Dry eye disorders
• Ocular surface disorders
• Mucopolysaccharides
• Neural chlamydial conjunctivitis
• Herpes simplex keratitis
• Herpes zoster ophthalmicus
• Allergic eye disease
• Alkali burns.

Procedure
The ocular surface is anesthetized with 1 to 2 drops of proparacaine
hydrochloride 0.5%. A 6 mm disk of cellulose acetate filter membrane with
one side cut off obliquely is placed, dull side down on the bulbar
conjunctiva; the cut edge of the disk faces the limbus. Uniform pressure
of 40 to 45 grams is applied for 10-15 seconds. The cellulose acetate filter
membrane is gently peeled from the ocular surface and placed specimen
side up on a glass slide.

Processing
Generally 1-3 layers are obtained on a filter membrane. Alcohol fixed smears
are stained with hematoxylin and eosin whereas air dried smears are stained
with Giemsa (Figure 12.1).
 CYTOPATHOLOGY OF THE EYE 97

Figure 12.1: Photomicrograph showing basophilic inclusion bodies capping the nucleus in
a case of trachoma (Giemsa stain, x 200)

Interpretation
Imprint cytology has utility in ocular surface disorders like ocular surface
squamous neoplasia and dry eye disorders. Dry eye cellular sample shows
increased keratinized cells with pyknotic nuclei (Figures 12.2A and B). In
keratoconjunctivitis sicca, the main feature is squamous metaplasia of
epithelial cells and altered goblet cell density.

Figures 12.2A and B: A. Imprint smear showing a sheet of normal epithelial cells with multiple
goblet cells (hematoxylin and eosin x 100); B. Photomicrograph showing multiple keratinized
epithelial cells and absence of goblet cells (hematoxylin and eosin x 400)

II. CORNEAL AND CONJUNCTIVAL SCRAPING

It is done in various disorders of the conjunctiva and cornea, with infections
forming the bulk of the indications (Fig. 12.3).

Indications
a. Infectious conditions: Trachoma, viral conjunctivitis, bacterial, fungal and
protozoal infections
b. Non-infectious conditions: Vernal conjunctivitis, pemphigoid, Hay fever
c. Degenerative changes: Keratoconjunctivitis sicca, vitamin A deficiency
d. Neoplastic conditions: Epithelial tumors.
98 MANUAL OF OCULAR PATHOLOGY

Procedure
Topical anesthesia (proparacaine hydrochloride 0.5%) is required.
A sterile kimura spatula is used for scarping or a No.15 blade may be used
as an alternative.
a. Corneal scraping: To obtain a corneal sample, the blade is held at an angle
of 30 degrees to the corneal surface and pressure is applied as the blade
is moved across the lesion. Great care has to be taken to avoid perforation.

Figure 12.3: Showing central corneal ulcer with feathery margin

b. Conjunctival scraping: It is performed most commonly from the inferior

fornix. However, the site of maximal involvement should always be scraped.
For example, the upper tarsal conjunctiva in trachoma (Figure 12.4).
Sufficient conjunctival material can be obtained by passing the spatula over
its surface, several times in the same direction with sufficient pressure to
blanch the blood vessels.

Processing
After the scraping, the material is sent to the pathology and microbiology
department. The slide are stained with hematoxylin and eosin as well as with
special stains like Grams, Periodic Acid Schiff and Gomari’s Methanamine
Silver Stain.

Cytopathological correlation

Conjunctiva
Neutrophils Acute infection
Plasma cells, inclusion bodies Trachoma
Eosinophils Allergic response, vernal conjunctivitis, Hay
fever, pemphigoid
Keratinized epithelium Keratoconjunctivitis sicca/vitamin A
deficiency
Atypical epithelial cells Malignancy
 CYTOPATHOLOGY OF THE EYE 99
Cornea
Bacteria, fungi (Figure 12.5) and protozoa (acanthamoeba) (Figure 12.6) can
be demonstrated in the material from the corneal scraping.

Figure 12.4: Showing technique of conjunctival scraping

Figure 12.5: PAS showing septate fungi in corneal scraping (PAS x 200)

Figure 12.6: Corneal scraping showing acanthamoeba (hematoxylin and eosin x 200)
100 MANUAL OF OCULAR PATHOLOGY

III. AQUEOUS TAP

Aqueous chamber paracentesis is a relatively simple outpatient procedure.

Indications
• Endophthalmitis
• Lens-induced uveitis
• Masquerade syndrome
• Parasitic uveitis
• Necrotizing retinitis.

Procedure
Prior instillation of broad spectrum antibiotic drops and local anesthesia is
required. A tuberculin or 2cc syringe with a 27 to 30 gauge needle is used.
In case of fibrin or granulomatous uveitis a large bore 25-26 gauge needle
is used. The needle is passed through the anterior chamber, obliquely through
the stroma, via the lower limbus with the beveled end facing upwards
throughout the procedure. Obtain a 0.1 to 0.3 ml yield of aqueous and on
withdrawal, external pressure is applied to the entrance with a sterile cotton
tipped applicator (Figures 12.7A and B).

Figures 12.7A and B: A. A clinical photograph showing collection of aqueous aspirate sample
by anterior chamber tap; B. Microphotograph showing collection of malignant tumor cells in
the aqueous aspirate sample in a case of metastatic tumor

Processing
As the amount of material is small, it should be handled carefully. In case
of infected uveitis and endophthalmitis, a portion of the material should be
sent to microbiology for direct smear culture and PCR. The remaining fluid
should undergo cytospin to obtain better cell recovery.

Interpretation (Figures 12.11 and 12.12 and Table 12.1)

Table 12.1: Cytopathologic finding of aqueous aspirate
Diagnosis Cytopathologic finding
Lens-induced uveitis Macrophages engulfing lens particles, acute and chronic
inflammatory cells (Figures 12.8A and B)
Contd...
 CYTOPATHOLOGY OF THE EYE 101
Contd...
Diagnosis Cytopathologic finding
Masquerade syndrome Malignant cells, e.g. retinoblastoma cells, leukemic cells (Figure
(retinoblastoma, leukemia) 12.7B)
Parasitic uveitis Eosinophils, polymorphs and sometimes parasites (Figure 12.8B)
Delayed endophthalmitis Propionibacterium acne on gram stain/culture/polymerase
following cataract chain reaction
extraction with IOL
implantation
Infectious endophthalmitis Bacteria, fungi (Figure 12.12B)
Viral uveitis Immunofluorescence study showing viruses (Figures 12.9 and
12.10)

Figures 12.8A and B: A. Uveitic eye with hypopyon; B. Photomicrograph showing a microfilaria
surrounded by polymorphonuclear leukocytes (hematoxylin and eosin x 200) from a case of
hypopyon uveitis

Figure 12.9: Slit lamp photograph of a HIV positive patient with hemorrhagic hypopyon

Figure 12.10: Immunofluorescence showing positive immunofluorescence with monoclonal

antibody against Varicella zoster virus (immunofluorescence x 400)
102 MANUAL OF OCULAR PATHOLOGY

IV. VITREOUS TAP

It is a technique which gives sufficient vitreous sample for cytopathological
analysis.

Figures 12.11A and B: A. Slit lamp photograph showing granulomatous uveitis following finger
nail injury; B. Photomicrograph of the same patient showing multiple macrophages engulfing
lens particles (hematoxylin and eosin x 200)

Figures 12.12A and B: A. Slit lamp photograph showing an exudative mass in anterior chamber
of a patient following cataract extraction; B. Photomicrograph showing multiple septate fungi
in KOH calcoflour preparation (KOH calcoflour x 200) from the same patient

Indications
• Endophthalmitis
• Infective posterior uveitis
• Recalcitrant posterior uveitis
• Suspected large cell lymphoma
• Acute retinal necrosis.

Procedure
The procedure is usually done in the operation theater using a surgical
microscope with a subconjunctival or retrobulbar injection. It can also be
performed in the outpatient department under sterile precautions.
Vitreous sampling is done using 25 to 23 gauge needles. Most eyes with
long-standing intraocular inflammation have liquefied vitreous or fluid pockets
within the vitreous. In such a situation, a fine bored 25-guage needle can be
used. When organization of vitreous is seen, a 23-gauge needle is preferred.
The vitreous sample is obtained with the use of a three-way stopcock. One
 CYTOPATHOLOGY OF THE EYE 103
end is attached to the needle and the other two openings are attached to a
tuberculin syringes. The globe is immobilized with conjunctival forceps and the
needle is inserted in the vitreous cavity under direct visualization with a slit lamp
microscope. The empty syringe withdraws the vitreous and manipulating the
stopcock, a similar quantity of antibiotic is injected into the vitreous cavity. After
the injection, the needle is slowly withdrawn from the eye.

Processing
The volume of sampled vitreous is relatively large compared to the aqueous
specimen. One half of the specimen is sent to microbiology for culture and
PCR and the other half of the sample is centrifuged by cytospin to prepare
a smear and for immunohistochemistry study.

Interpretation (Table 12.2)

Table 12.2: Cytologic findings of vitreous tap
Diagnosis Findings
Phacoanaphylactic Lens fragments surrounded by polymorphs, epithelioid cells and
uveitis/endophthalmitis giant cells
Large cell lymphoma Large pleomorphic cells with prominent round or oval nuclei and
(Reticulum cell sarcoma) scanty cytoplasm. Micronuclei are also present in such cells
Endophthalmitis Acute/chronic inflammatory cells and causative organisms e.g.
fungi, bacteria on appropriate stains
Uveitis Heterogenous lymphocytic infiltrate

V. FINE NEEDLE ASPIRATION BIOPSY (FNAB)

FNAB offers a histological correlation to the clinical diagnosis in cases of
atypical presentation of intraocular lesion. It aids in effective planning and
management and also enables histopathological diagnosis without having
to sacrifice the eye or having to resort to open biopsy method.

Indications
• Epithelial malignancies
• Metastatic tumors
• Infection
• Fibrous tumor
• Pseudotumor of orbit.
The Limbal route is used to approach anterior uveal lesions, e.g. iris lesions
or in aphakic patients for posterior ciliary body lesions.
In the posterior segment lesions, the possible approaches are:

Pars Plana Transvitreal Approach

In this approach, the needle is passed from the pars plana region (3.5 mm
from the limbus) in the quadrant opposite to the lesion, through the vitreous
104 MANUAL OF OCULAR PATHOLOGY

gel. For some of the eyes with tumors located posteriorly; a vitrectomy needs
to be performed before aspiration. The purpose of vitrectomy is as follows:
1. To maintain clear visualization of the lesions and the needle path.
2. To remove the vitreous that could potentially adhere to the needle, hence
reducing unnecessary retinal traction.
3. To eliminate adherence of tumor cells in the needle to the vitreous as the
needle is withdrawn (mitigate potential of tumor cells tracking in the
wound).
4. To control bleeding after aspiration.

Corneolimbal Approach
This approach through the zonules prevents dissemination of the tumor mass
through the needle track. This approach is used in patients with
retinoblastoma, a highly friable tumor, as the chance of needle track
dissemination is extremely high. Through a corneolimbal approach the needle
passes through multiple planes, thus wiping out the tumor cells as the needle
is removed from the eye. In addition the absence of blood vessels theoretically
decreases the chances of dissemination.

Subretinal FNAB
This can be done in cases of subretinal abscesses, tuberculomas and large
cell lymphoma (Figures 12.13A and B and 12.14) considering the site is
approachable.
Most surgeons prefer to use a 25-gauge needle with a flexible connector
to a 2-ml syringe to minimize the movement and surgical trauma during
biopsy. Others prefer a spinal needle with a trochar and cannula, although
the excess movement caused by removing the trochar and attaching the syringe
and flexible connector may lead to increased complications.

Figures 12.13A and B: A. Montage photograph showing multifocal creamy yellow subretinal
plaque lesion in a patient; B. Photomicrograph showing necrotic cellular material within which
large lymphoma cells (hematoxylin and eosin x 200) from the same patient
 CYTOPATHOLOGY OF THE EYE 105

Figure 12.14: Photomicrograph of FNAB material from the orbit showing monomorphic
lymphoid cells suggestive of lymphoma (hematoxylin and eosin x 100)

Complications
1. The most common complication of FNAB is bleeding from the site of the
needle track. Virtually all intraocular FNABs are associated with a small
degree of hemorrhage, which can be subretinal, retinal or in the vitreous
cavity.
2. Orbital dissemination of tumor cells and distant metastatic spread caused
by tumour implantation along the needle track has been reported. These
are greatly reduced with the use of smaller 25-gauge needles. Theoretically
this procedure can also disseminate a subretinal focus of infection.
3. Iatrogenic retinal perforations are unavoidable by the indirect needle
approach to the choroidal lesions and can theoretically cause a retinal
detachment after FNAB. The numbers of cases developing these retinal
detachments following FNAB are few, possibly because the blood clot
usually closes the site of perforation.

Processing
The sample is taken and processed to form smears and a cell block and stained
with hematoxylin and eosin and special stains like Gomori’s methenamine
silver, Warthin starry stain and Acid-Fast stains, as well as
immunohistochemical stains using antibodies.

Orbital FNAB
FNAB has been used successfully for lymphoid lesions of the orbit and for
detecting metastatic tumor. It provides a definite diagnosis whether the lesion
is primary or metastatic. However in cases of hemorrhagic cystic lesions and
desmoplastic tumors, it is not useful as it may not yield cellular material for
cytological studies.
106 MANUAL OF OCULAR PATHOLOGY

Summary
Cytopathology is a very useful diagnostic technique in ophthalmology.
However, it requires a pathologist experienced in ophthalmic pathology. A
portion of the specimen should be submitted to microbiology in cases of
suspected infective etiology.

Applications
1. Anterior segment:
a. Conjunctiva
b. Cornea
c. Anterior chamber aspirate.
2. Posterior segment:
- Vitreous.
- Needle biopsy of intraocular tumors in selective cases.
3. Orbit: Fine needle aspiration biopsy.

Anterior Segment
Conjunctiva
A. Infectious conditions:
- Trachoma
- Viral conjunctivitis
- Bacterial and fungal infection.
B. Non-infectious conditions:
- Vernal conjunctivitis
- Hay fever conjunctivitis
- Pemphigoid.
C. Degenerative changes:
- Keratoconjunctivitis sicca
- Vitamin A deficiency.
D. Neoplastic conditions:
- Epithelial tumor (biopsy to confirm).

Cytopathologic Correlation
Neutrophils Acute infection
? bacteria
? fungal
Plasma cells Trachoma
Eosinophils Allergic response
Vernal conjunctivitis
Hay fever
Pemphigoid
 CYTOPATHOLOGY OF THE EYE 107
Atypical epithelial cells
- ? basal cell carcinoma
- ? squamous cell carcinoma (biopsy to confirm).
Keratinized epithelium
- Keratoconjunctivitis sicca
- Vitamin A deficiency.

Special Techniques
Indirect immunofluorescent staining
- Pemphigoid
- Trachoma.
Imprint smear
- Vitamin A deficiency
- Ocular surface eye disorder.
Imprint smear is taken by pressing Millipore filter paper strips on the surface
of the conjunctiva and is stained with PAS stain. Goblet cells of the conjunctiva
are PAS-positive. The deficiency of these cells, if noted microscopically,
indicates mucin-deficiency and dry eye state.

Diagnostic Possibilities and Technique of Choice

Bacteria—Dry smear-Gram’s stain
Fungus—KOH preparation, PAS stain or GMS
Inflammatory process—Giemsa/H&E
Neoplasm—Papanicolaou
Not sure—H & E and decide.

Cytopathology of Intraocular Fluid/Tissue Specimen

This application is most useful in the following conditions:

Inflammatory Conditions
- Endophthalmitis
- Lens-induced uveitis
- Recalcitrant uveitis.

Neoplasms
- Reticulum cell sarcoma
- Juvenile xanthogranuloma
- Metastatic carcinoma.
108 MANUAL OF OCULAR PATHOLOGY

Secondary Glaucoma
- Phacoanaphylactic
- Blood induced
- Melanomalytic.

Others
- Amyloidosis
- Acute retinal necrosis
Intraocular fluid Specimen was submitted in one piece to pathology.

Collection:
- Sterile technique, mandatory
- Immediately in the operation theatre.

Approach
i. Smear for direct examination
ii. Culture for infective organisms
iii. Freeze if immunological study is anticipated.

Fine Needle Aspiration Biopsy

Orbit
Most helpful:
- Epithelial malignancies
- Metastatic tumors
- Lymphoid tumors (with immunoperoxidase techniques)
- Infections.

Not very helpful:

- Fibrous tumor (schwannoma, neurofibroma)
- Pseudotumor of orbit.

Not helpful at all:

- Rhabdomyosacroma
- Fibrous histiocytoma
- Vascular tumors.
110 MANUAL OF OCULAR PATHOLOGY

Frozen section diagnosis is extensively used in various branches of pathology,

but its application in ophthalmic pathology was recognized only in the 1970s.
Diagnosis by frozen section is commonly employed in all surgical
specialties. In recent years however, there has been a significant increase in
its application in ophthalmic surgery. This technique is used to make a reliable
identification of the pathological nature and extent of lesions within a period
of 15 to 20 minutes. Special stains for fat and certain immunohistochemical
studies, particularly immunofluorescence, can also be performed on frozen
sections.
The instrument used for frozen section is a cryostat. It consists of a rotary
microtome enclosed in mechanically refrigerated cabinet. It has a platform
to freeze tissue rapidly and most have the capacity to self defrost. In the
controlled environment of the cryostat, the microtome blade, cabinet interior
and instruments are all maintained at the same operating temperature
(-19oC to -21oC) (Figures 13.1 and 13.2).

Figure 13.1: Showing cryostat instrument for taking frozen sections

 FROZEN SECTION 111

Figure 13.2: Showing frozen section of squamous cell carcinoma with keratin pearl (arrow)
114 MANUAL OF OCULAR PATHOLOGY

The eye is one of the organs commonly affected by primary or secondary

pathological processes in multisystem involvement of acquired immune
deficiency syndrome (AIDS). Ocular disease is present in approximately 75%
of patients suffering from AIDS.
Anterior segment lesions in AIDS patients are as follows:
Kaposi’s sarcoma is the most common lesion involving the anterior segment
of the eye and it is seen in about 30% of AIDS patients. In the eyelid, Kaposi’s
sarcoma appears similar to other skin lesions as purplish nodules and
discoloration of the skin.
In the conjunctiva, similar lesions may be seen. Approximately 18% of
patients suffering from Kaposi’s sarcoma have conjunctival involvement.
Histopathologically, Kaposi’s sarcoma is comprised of spindle-shaped cells
in a fascicular arrangement with multiple vascular channels and slit-like spaces
containing erythrocytes.
Corneal involvement with cytomegalovirus (CMV), herpes simplex or
herpes zoster keratoconjunctivitis, is observed in 10% of AIDS patients.

POSTERIOR SEGMENT LESIONS IN AIDS

Retina
The retina is commonly involved in AIDS, with about 58% per cent of patients
showing some retinal pathology. These pathologic changes consist of non-
infectious vascular disorders and/or opportunistic infections.

Noninfective Vascular Disorders

Cotton wool spots (cytoid bodies) are the most common lesions, occurring
in approximately 50% of AIDS patients. Clinically, they appear as discrete
fluffy opacities in the superficial retina, usually in the posterior pole adjacent
to the major vascular arcades. They indicate focal ischemia in the nerve fiber
layer, resulting in stasis of axoplasmic outflow. Histologically, the cytoid bodies
involve primarily the inner layer of the retina. The ganglion cell and nerve
fiber layers are greatly thickened by a disciform, sharply circumscribed lesion.
Retinal hemorrhages are seen in 15 to 40% of AIDS patients. Histologic
examination of Roth’s spot located in the posterior pole showed hemorrhages
in the superficial and deep layers of the retina and subtle cytoid bodies in
the nerve fiber layer.

Opportunistic Infections of the Retina

Cytomegalovirus retinopathy is the most common opportunistic infection in
AIDS patients, occurring in 26 to 46% of the cases.
Grossly, globes removed at autopsy show dry, white granular retinal
opacification, adjacent to retinal vessels, from the posterior pole to the
periphery. Histologically, extensive areas of full-thickness retinal and retinal
 OCULAR PATHOLOGY IN AIDS 115
pigment epithelial necrosis have been observed. Sharp demarcation between
involved and uninvolved retina has been noticed by many investigators.
Typical intranuclear and intracytoplasmic inclusion bodies have been observed
in all layers of the involved retina, including the retinal pigment epithelium.

Bacterial Infections of the Retina

1. Syphilis.
2. Mycobacterium avium-intracellulare.

Fungal Infections of the Retina

1. Candida
2. Cryptococcus
3. Histoplasma
4. Sporothrix.

Protozoal Infections of the Retina

1. Toxoplasma gondii.
2. Pneumocystis carinii – Rao et al reported clinical, histopathologic and electron
microscopic study of three cases of pneumocystic carinii choroiditis in AIDS
patients. On gross examination, the globe showed many choroidal
infiltrations. Histopathology of the infiltrates showed eosinophilis, acellular
and frothy masses which on Gomori’s methenamine silver stain
demonstrated many cystic, crescentic organisms. Electron microscopy
revealed thick-walled cystic organisms and a large number of trophozoites
of pneumocystis carinii.

Orbital Involvement
- Burkitt’s lymphoma
- Kaposi’s sarcoma.
118 MANUAL OF OCULAR PATHOLOGY

Sankara Nethralaya established Teleophthalmic pathology one year ago. We

have performed 25 cases of teleophthalmic pathology to date. This involves
the use of telecommunication technology at remote locations by viewing
images on a visual display unit (computer) instead of direct visualization on
bright field light microscope (Figure 15.1). On an average, each case comprises
of 5 images (range 4-6) with a total dimension of 300 kilobytes. The mean
time needed for the acquisition of imaging for each case is on average 3 minutes
and an average of 5 minutes for transmission, resulting in an overall of 8
minutes.
In one case, however, the teleophthalmic pathology consultant required
to see the slide directly before giving the report. We are in the process of
publishing an article on ophthalmic telepathology concepts and practice and
our results in the Indian Journal of Pathology and Microbiology.

Figure 15.1: Showing telepathology set up

120 MANUAL OF OCULAR PATHOLOGY

SANKARA NETHRALAYA PUBLICATIONS IN OPHTHALMIC PATHOLOGY

1. Biswas J, Badrinath SS, Rao NA: ‘Primary non-familial amyloidosis of
the vitreous - A light microscopic and electron microscopic study.’
Retina 1992;12:252-53.
2. Biswas J: ‘Pathology of uveitis’. Afro-Asian J Ophthalmol 1992;9(3):
206-09.
3. Lakshmi SG, Biswas J, Natarajan K, Padmanabhan P, Madhavan HN:
Acanthamoeba keratitis - Clinicopathological study of 6 cases. Afro-Asian
J Ophthalmol 1993;Vol. XII, No. 1.
4. Biswas J, Subramanian N: Frozen section diagnosis in ophthalmic
pathology Ind. J Ophthalmol 1993;41(3):114-16.
5. Biswas J, Gopal L, Sharma T, Badrinath SS: Intraocular Gnasthostoma
Spinigerum—Clinicopathological Study of Two Cases with Review of
Literature’—Retina 1994;14:438-44.
6. Biswas J, Neelakantan A, Rao BS: Adenoma of nonpigmented epithelium
of ciliary body presenting as anterior uveitis and glaucoma. Ind. J
Ophthalmol 1995;43:137-40.
7. Biswas J, Shanmugam MP, Gopal L: Malignant melanoma of the choroid
in association with oculodermal melanocytosis—A case report. Ind J
Ophthalmol, 1995;43:140-41.
8. Biswas J, Madhavan HN, Gopal L, Badrinath SS Intraocular tuberculosis.
Retina 1995;15:461-68.
9. Biswas J, Chandran TC, Natarajan G Periorbital giant congenital
melanocytic nevus with malignant changes—A clinicopathological
study. Orbit 1996;15(1).
10. Biswas J, Shanmugam MP, Parikh S, Patwardhan D, Badrinath SS
Retinoblastoma in adults—Report of two cases with histopathological
correlation. Asia Pacific J Ophthalmol 1996;8:14-18.
11. Biswas J, Fogla R, Srinivasan N, Narayan S, Haranath K, Badrinath V
Clinical and Histopathological findings of ocular malaria—A study of
three cases. Ophthalmology 1996;103:9.
12. Biswas J, Fogla R: Sympathetic Ophthalmia following Cyclocryotherapy
—Report of a case with histopathological correlation. Ophthalmic
Surgery and Laser 1996;27:1035-1308.
13. Biswas J, Dutta M, Subramaniam N: Mucoepidermoid carcinoma of the
conjunctiva of the lower lid. Ind J Ophthalmol 1996;44:231-33.
14. Shanmugam MP, Biswas J Fine needle aspiration biopsy in the diagnosis
of intraocular mass lesions. Ind J Ophthalmol 1997;45:105-08.
15. Biswas J, Madhavan HN, Badrinath SS Demonstration of herpes simplex
virus from lens aspirate in healed acute retinal necrosis (ARN) syndrome.
Bri J Ophthalmol 1997;81(9):802-803.
 REFERENCES 121
16. Biswas J, Lily Therese, Kumarasamy N, Solomon S: Lid abscess with
extensive molluscum contagiosum in a patient with acquired
immunodeficiency syndrome (AIDS). Ind. J Ophthalmol 1997;45;234-36.
17. Biswas J Souza CD, Shanmugam MP: Diffuse melanotic lesion of the
iris as a presenting feature of ciliary body melanocytoma—Report of
a case and reivew of the literature. Survey of Ophthalmol 1998;42:4.
18. Biswas J, Raizada S: Immunopathology of uveitis. Ind J Lepr 1998; 70(1):
11-25.
19. Biswas J, Therese L, Madhavan HN: Use of polymerase chain reaction
(PCR) in the detection of Mycobacterium tuberculosis complex DNA from
aqueous sample of suspected tuberculosis uveitis. Uveitis Today
(Proceedings of the Fourth International Symposium on Uveitis,
Yokohama, Japan, 10-14 October, 1997) 1998;227-30.
20. Biswas J, Gopal L, Sharma T, Parikh S, Madhavan HN, Badrinath SS:
Recurrent cryptococcal choroiditis in a renal transplant patient—
Clinicopathological study. Retina 1998;18(3):273-76.
21. Rajeev B, Biswas J: Molecular biologic techniques in ophthalmic
pathology. Ind J Ophthalmol 1998;46:3-13.
22. Badrinath SS, Gopal L, Sharma T, Parikh S, Shanmugam MP, Bhende
P, Biswas J: Vitreoschisis in Eales’ disease—pathogenic role and
significance in surgery. Retina 1999;19:51-54.
23. Wagle AM, Biswas J, Subramanian N, Mahesh L: Primary liposarcoma
of the orbit—A clinicopathological study. Orbit 1999;18(1):33-36.
24. Biswas J, Therese L, Madhavan HN: Use of polymerase chain reaction
in detection of Mycobacterium tuberculosis complex DNA from vitreous
sample of Eales’ disease. Br J Ophthalmol 1999;83:994.
25. Biswas J, Bhende P, Gopal L, Parikh S, Badrinath SS: Subconjunctival
cyst following silicone oil injection—Clinicopathological study of five
cases. Ind J Ophthalmol 1999 47(3):177-180.
26. Biswas J, Ahuja VK, Shanmugam MP, Kurian R, Fernandez T. Malignant
melanoma of the choroid presented as orbital cellulitis—Report of two
cases with review of literature. Orbit 1999;18(2):123-30.
27. Castelino AM, Rao SK, Biswas J, Gopal L, Madhavan HN, Kumar KS:
Conjunctival rhinosporidosis associated with scleral melting and
staphyloma formation – diagnosis and management. Cornea 2000;19
(1):30-33.
28. Rao SK, Biswas J, Rajagopal R, Sitalakshmi, Padmanabhan P. Ligneous
conjunctivitis: A clinicopathologic study of 3 cases. Int. Ophthalmol 1999;
22:201-06.
29. Fogla R, Rao SK, Biswas J: Avoiding conjunctival necrosis after periocular
depot corticosteroid injection. J Cataract Surg. 2000;26:163-64.
122 MANUAL OF OCULAR PATHOLOGY

30. Fogla R, Biswas J, Parikh S, Madhavan HN: Micrococcal endophthalmitis

following extracapsular cataract extraction with foldable silicone
intraocular lens implantation. Ind J Ophthalmol 2000; 48(1) 50-52.
31. Madhavan HN, Therese KL, Gunisha P, Jayanthi U, Biswas J. Polymerase
chain reaction for detection of Mycobacterium tuberculosis in epiretinal
membrane in Eales’ disease. IOVS 2000;41(3):822-25.
32. Biswas J, Krishnakumar S, Gopal L, Bhende MP: Leiomyoma of the ciliary
body extending to the anterior chamber – clinicopathological and
ultrasound biomicroscopic correlation. Survey of Ophthalmol. 2000;
44:336-42.
33. Biswas J, Mani B, Shanmugam MP, Patwardhan D, Kumar KS, Badrinath
SS. Retinoblastoma in adults—Report of 3 cases and review of literature.
Survey of Ophthalmol 2000; 44(5):409-14.
34. Fogla R, Biswas J, Krishnakumar S, Madhavan HN, Kumarasamy N,
Solomon S. Squamous cell carcinoma of the conjunctiva as initial
presenting sign in a patient with acquired immunodeficiency syndrome
(AIDS) due to human immunodeficiency virus type-2. Eye 2000;14(2):
246-47.
35. Biswas J, Raghavendran SR, Ratra V, Krishnakumar S, Gopal L,
Shanmugam MP: Diffuse malignant melanoma of the choroid simulating
metastatic tumor in the choroid. Ind J Ophthalmol 2000;48:137-40.
36. Ramaswamy AA, Biswas J, Bhaskar V, Gopal L, Rajagopal R, Madhavan
HN. Postoperative Mycobacterium chelonae endophthalmitis following
extracapsular cataract extraction and posterior chamber intraocular lens
implantation. Ophthalmology 2000;107:1283-286.
37. Biswas J, Krishnakumar S, Shanmugam MP, raghavendran SR Clear
cell thyroid carcinoma metastatic to choroid—Clinicopathological study
of a case. Eye 2000;14:394-95.
38. Biswas J, Krishna kumar S, Raghavendran RS, Mahesh L. Lid swelling
and diplopia as presenting features of orbital sarcoidosis—Report of a
case. Ind J Ophthalmol, 2000;48:231-33.
39. Samanta TK, Biswas J, Gopal L, Anand AR, Kumarasamy N, Solomon
S. Panophthalmitis due to Rhizopus in an AIDS patient: A
clinicopathological study, 2001;49:49-51.
40. Mahesh L, Biswas J, Subramanian N: Role of ultrasound and CT scan
in diagnosis of hydatid cyst of the orbit. Orbit 2000; 19(3):179-88.
41. Biswas J, Chowdhury BR, Kumar KS, Therese KL, Madhavan HN.
Detection of Mycobacterium tuberculosis by polymerase chain reaction in
a case of orbital tuberculosis. Orbit 2001;20(1):69-74.
42. Biswas J, Babu K, Krishnakumar S, Vanitha K, Vaijayanthi K. Gross
photography of ophthalmic specimens. Ind J Ophthalmol, 2001;49:273-
76.
 REFERENCES 123
43. Biswas J, Krishna Kumar S, Rupauliha, Misra S, Bharadwaj I, Therese
L. Detection of Mycobacterium tuberculosis by nested polymerase chain
reaction in a case of subconjunctival tuberculosis. Cornea 2002;21(1):123-
25.
44. Biswas J, Krishnakumar S. Cytopathology of explanted IOLs and their
clinical correlation. J of Cataract and Refract Surg 2002;28:538-543.
45. Mohan ER, Biswas J, Kumar KS. Oncocytoma of the caruncle — A case
report. Ind J Ophthalmol 2002;50:60-61.
46. Biswas J, Krishnakumar S, Shanmugam MP. Uveal melanomas in Asian
Indians – A clinicopathological study. Archives of Ophthalmol 2002;
120:522-523.
47. Biswas J, Krishnakumar S, Bhavsar K, Shanmugam MP. Choroidal
metastasis of a gingival squamous cell carcinoma — A case report. Am
J of Ophthalmol 2002; 133(5):713-5.
48. Gangadharsundar JK, Krishnakumar S, Biswas J. Retinoblastoma
presenting as panophthalmitis — Clinicopathological study of a case.
J of Pediatr Ophthalmol and Strabismus 2002;39(3):178-80.
49. Biswas J, Raman R, Age-related changes in the macula —
Histopathological study of fifty Indian donor eyes. Ind J Ophthalmol
2002;50:201-4.
50. Biswas J, Shome D. Choroidal tubercles in disseminated tuberculosis
diagnosed by PCR of aqueous humor—J of Ocular Immunol and
Inflammation Ocul Immunol Inflamm 2002;10(4):293-98.
51. Rambhatla S, Subramanian N, Gangadharsundar JK, Krishnakumar S,
Biswas J. Myxoma of the orbit — A case report. Ind J Ophthalmol 2003;
51:85-87.
52. Biswas J, Krishnakumar S. Choroidal melanoma in a black patient with
oculodermal melanocytosis. Retina; 2003;23:126.
53. Sharma T, Sinha S, Shah N, Gopal L, Shanmugam MP, Bhende P, Bhende
M, Shetty NS, Agarwal R, Deshpande D, Biswas J, Sukumar B. Intraocular
cysticercosis: Clinical characteristics and visual outcome after vitrectomy
surgery. Ophthalmology 2003; 110 (5):996-1004.
54. Krishnakumar S, Babu K, Das D, Biswas J. A clinicopathological study
of a case of sinus histiocytosis with massive lymphadenopathy
mimicking an optic nerve tumor. J of Pediatric Ophthalmol and
Strabismus 2003;40(3):172-75.
55. Gopal L, Rao SK, Biswas J, Madhavan HN, Agarwal S. Tuberculous
granuloma managed by full thickness eye wall resection. Am J
Ophthalmol 2003;135:93-94.
56. Krishnakumar S, Mohan ER, Babu K, Das D, Biswas J. Eccrine duct
carcinoma of the eyelid mimicking meibomian carcinoma —
Clinicopathological study of a case. Surv Ophthalmol 2003;48:439-46.
124 MANUAL OF OCULAR PATHOLOGY

57. Ganesh SK, Babu K, Krishnakumar S, Biswas J. Ocular filariasis due

to Wuchereria bancrofti presenting as panuveitis: A case report. Ocul
Immunol Inflamm 2003;11:145-48.
58. Krishnakumar SK, Subramanian N, Mahesh L, Mohan ER, Biswas J.
Primary ductal adenocarcinoma of the lacrimal gland in a patient with
neurofibromatosis. Eye 2003;17(7):843-45.
59. Krishnakumar S, Abhyankar D, Sundaram AL, Pushparaj V,
Shanmugam MP, Biswas J. Major Histocompatibility Antigens and
Antigen-processing Molecules in Uveal Melanoma. Clin Cancer Res 2003;
15;9(11):4159-64.
60. Krishnakumar S, Subramanian N, Mohan ER, Mahesh L, Biswas J, Rao
NA. Solitary fibrous tumor of the orbit: A clinicopathologic study of
six cases with review of the literature. Surv Ophthalmol 2003;48(5):
544-54.
61. Shanmugam MP, Amirtha Lakshmi S, Biswas J, Krishnakumar S.
Prognostic significance of Fas expression in retinoblastoma. Ocul
Immunol Inflamm 2003;11:107-13.
62. Biswas J, Narayana KN, Gupta S, Malathi J, Madhavan HN. Panuveitis
due to acquired rubella and isolation of rubella from the aqueous humor.
J Pediatr Ophthalmol Strabismus 2003;40(4):240-42.
63. Biswas J, Das D, Krishnakumar S, Shanmugam MP. Histopathologic
analysis of 232 eyes with retinoblastoma conducted in an Indian
tertiary — care ophthalmic center. J Pediatr Ophthalmol Strabismus
2003;40:265-67.
64. Abhyankar D, Lakshmi SA, Pushparaj V, Biswas J, Krishnakumar S. HLA
class II antigen expression in conjunctival precancerous lesions and
squamous cell carcinomas. Curr Eye Res 2003;27(3):151-55.
65. Krishnakumar S, Lakshmi SA, Abhyankar D, Biswas J. Expression of
HLA class I, B2 microglobulin and HLA class II antigens in primary
orbital melanoma. Orbit 2003;22:257-64.
66. Krishnakumar S, Lakshmi SA, Abhyankar D, Biswas J. Loss of antigen
processing molecules in primary orbital melanoma. Orbit 2003;22:
265-70,.
67. Bhattacharjee K, Bhattacharjee H, Das D, Babu K, Krishnakumar, Biswas
J. Chloroma of the orbit in a non-leukemia adult: A case report. Orbit
2003;22:293-98.
68. Mahesh L, Krishnakumar S, Subramanian N, Babu K, Biswas J. Malignant
teratoma of the orbit: A clinicopathological study of a case. Orbit 2003;
22:305-10.
69. Krishnakumar S, Lakshmi A, Shanmugam MP, Vanitha K, Biswas J.
Nm23 expression in retinoblastoma. Ocul Immunol Inflamm 2004;
12:127-35.
 REFERENCES 125
70. Krishnakumar S, Sundaram A, Abhyankar D, Krishnamurthy V,
Shanmugam MP, Gopal L, Sharma T, Biswas J. Major histocompatibility
antigens and antigen-processing molecules in retinoblastoma. Cancer
1;100(5):1059-69, 2004.
71. Biswas J, Kabra S, Krishnakumar S, Shanmugam MP. Clinical and
histopathological characteristics of uveal melanoma in Asian Indians.
A study of 103 patients. Ind J Ophthalmol 2004;52:41-44.
72. Memon SV, Shome D, Mahesh L, Subramanian N, Krishnakumar S,
Biswas J, Noronha OV. Thrombosed orbital varix — A correlation
between imaging studies and histopathology. Orbit 2004; 23:13-18.
73. Krishnakumar S, Rambhatla S, Subramanian N, Mahesh L, Biswas J.
Recurrent mucinous carcinoma of the eyelid. Ind J Ophthalmol 2004;
52:156-57.
74. Biswas J, Babu K, Krishnakumar S, Shanmugam MP. Uveal metastasis
from a bronchial carcinoid tumor. Ind J Ophthalmol, 2004; 52:160-62.
75. Subramanian N, Krishnakumar S, Baby K, Mohan ER, Lakshmi KS,
Biswas J. Adult onset Langhan’s cell histiocytes of the orbit — A case
report. Orbit 2004;23:99-103.
76. Agarwal M, Biswas J, Krishnakumar S, Shanmugam MP. Retinoblastoma
presenting as orbital cellulitis report of four cases with a review of the
literature. Orbit 2004;23:93-98.
77. Bhende P, Babu K, Kumari P, Krishnakumar S, Biswas J. Solitary retinal
astrocytoma in an infant. J Pediatr Ophthalmol Strabismus 2004;
41(5):305-75.
78. Krishnakumar S, Kandalam M, Mohan A, Iyer A, Venkatesan N, Biswas
J, Shanmugam MP. Expression of Fas ligand in retinoblastoma. Cancer.
2004; 1;101(7):1672-76.
79. Krishnakumar S, Abhyankar D, Lakshmi SA, Pushparaj V, Shanmugam
MP, Biswas J. HLA expression in choroidal melanomas: Correlation with
clinicopathological features. Curr Eye Res 2004;28(6):409-16.
80. Krishnakumar S, Mohan A, Mallikarjuna K, Venkatesan N, Biswas J,
Shanmugam MP, Ren-Heidenreich L. EpCAM expression in
retinoblastoma: A novel molecular target for therapy. Invest Ophthalmol
Vis Sci 2004; 45(12):4247-50.
81. Gopal L, Babu EK, Gupta S, Krishnakumar S, Biswas J, Rao NA.
Pigmented malignant medulloepithelioma of the ciliary body. J Pediatr
Ophthalmol Strabismus 2004;41(6):364-66.
82. Agarwal S, Shanmugam MP, Gopal L, Krishnakumar S, Biswas J.
Necrotic melanocytoma of the optic disk with central retinal vascular
obstruction. Retina 2005;25(3):364-67.
83. Mahesh G, Giridhar A, Biswas J, Saikumar SJ, Bhat A. A case of periocular
dirofilariasis masquerading as a lid tumour. Indian J Ophthalmol 2005;
53(1):63-64.
126 MANUAL OF OCULAR PATHOLOGY

84. Subramanian N, Rambhatla S, Mahesh L, Menon SV, Krishnakumar S,

Biswas J. Cystic schwannoma of the orbit – A case series – A case report.
Orbit 2005; 24:125-29.
85. Babu RB, Sudharshan S, Kumarasamy N, Therese L, Biswas J. Ocular
tuberculosis in aquired immunodeficiency syndrome. Am J Ophthalmol
2006;142:413-18.
86. Mallikarjuna K, Pushparaj V, Biswas J, Krishnakumar S. Expression of
insulin-like growth factor receptor (IGF-1R), c-Fos, and c-Jun in uveal
melanoma: An immunohistochemical study. Curr Eye Res 2006;
31(10):875-83.
87. Adithi M, Venkatesan N, Kandalam M, Biswas J, Krishnakumar S.
Expressions of Rac1, Tiam1 and Cdc42 in retinoblastoma. Exp Eye Res
2006; 83(6):1446-52, Epub 2006.
88. Biswas J, Ho TC, Bhavsar K. Bilateral metastasis to the retina, choroids
and optic nerve from breast cancer: A clinicopathological case. Indian
J Ophthalmol 2007;55(1):71-72.
89. Agarwal M, Biswas J, Mathur U, Sijwali MS, Singh AK. Aspergillus iris
granuloma in a young male: A case report with review of literature.
Ind J Ophthalmol 2007;55(1):73-74.
90. Mohan A, Nalini V, Mallikarjuna K, Biswas J, Krishnakumar S.
Expression of motility-related protein MRP1/CD9, N-cadherin, E-
cadherin, alpha-catenin and beta-catenin in retinoblastoma. Exp Eye Res
9; 2007, [Epub ahead of print]
91. Mallikarjuna K, Vaijayanthi P, Biswas J, Krishnakumar S. Expession of
Epidermal Growth Factor Receptor, Ezrin, Hepatocyte Growth Factor,
and c-Met in Uveal Melanoma: An immunohistochemical study. Curr
Eye Res 2007;32:1-10.
92. Shankar S, Biswas J, Gopal L, Bagyalakshmi R, Therese L, Borse NJ.
Anterior chamber exudative mass due to Scedosporium apiospermum in
an immunocompetent individual. Ind J Ophthalmol 2007;55(3):226-27.
93. Biswas J, Singh C, Mukherjee B, Rama Kumar G. Panophthalmitis due
to Aspergillus in an acquired immunodeficiency syndrome patient:
Clinicopathological study of a case. Ind J Ophthalmol 2007;55(3):239-40.
94. Mukherjee B, Biswas J, Raman M. Subconjunctival larva migrans caused
by sparganum. Ind J Ophthalmol 2007; 55(3):242-3.
95. Mahendradas P, Biswas J, Khetan V. Fibrinous anterior uveitis due to
cysticercus cellulosae. Ocul Immunol Inflamm 2007; 15(6):451-54.
96. Madhavan J, Ganesh A, Roy J, Biswas J, Kumaramanickavel G. The
relationship between tumor cell differentiation and age at diagnosis in
retinoblastoma. J Pediatr Ophthalmol Strabismus 2008;45:22-25.
97. Mukherjee B, Biswas J. Soliary fibrous tumor of the orbit. Ind J Pathol
Microbiol 2008; 51(3):453-55.
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98. Biswas J, Verma A, Davda MD, Ahuja S, Pushparaj V. Intraocular tissue
migration of silicone oil after silicone oil tamponade: A histopathological
study of enucleated silicone oil-filled eyes. Ind J Ophthalmol 2008;
56(5):425-28.
99. Rishi P, Rishi E, Biswas J, Nandi K.Clinical and histopathological features
of posttraumatic iris cyst. Indian J Ophthalmol. 2008;56(6):518-21.
100. Mohan A, Venkatesan N, Kandalam M, Pasricha G, Acharya P, Khetan
V, Gopal L, Sharma T, Biswas J, Krishnakumar S. Detection of human
papillomavirus DNA in retinoblastoma samples: A preliminary study.
J Pediatr Hematol Oncol 2009;31(1):8-13.
128 MANUAL OF OCULAR PATHOLOGY

FURTHER READING
1. Apple DJ, Naumann GOH. General Anatomy and Development of the
Eye: Techniques of Investigation. Human Pathol 1982;13:1-18.
2. Apple DJ, Rabb MF. 1985. Ocular Pathology: Clinical Applications and
Self-assessment 3rd edn 1985.
3. Biswas J, Subramaniam N. Frozen section diagnosis in ophthalmic
pathology. Ind J Ophthalmol 1993;41:114-16.
4. Green WR Diagnostic cytopathology of ocular fluid specimens:
Ophthalmology 1984;91(6): 726-48.
5. Grossniklans HE, Green WR: Conjunctival lesions in adults — A clinical
and histopathologic review Cornea 1987;6(2):78-116.
6. Mclean IW, Foster WD, Zimmerman LE. Uveal melanoma: Location size,
cell type and enucleation as risk factors in metastasis, Human Pathol
1982; 13:123-32.
7. Naumann GOH, Apple DJ. Pathology of the Eye, 1986.
8. Rao NA, and Biswas J , Ocular pathology in AIDS: Ophthalmology clinics
of North America 1988;1:63-72.
9. Sang DN, Albert Dm. Retinoblastoma: Clinical and histopathologic
features. Human Pathol 1982;13:133-46.
10. Spencer WH (Ed) Ophthalmic Pathology: An Atlas and Textbook rd edn
1985.
11. Yanoff M. Fine BS Ocular Pathology: A Text and Atlas, 2nd edn. 1982.
 INDEX

A Different tissues within orbit 82

Age 61 Diseases of
Angiomatous lesions 23 retina 69
Anterior segment 106 vitreous 77
Applications 106 Dystrophies 40
Approach 108
Aqueous tap 100 E
Asteroid hyalosis 78 Embryonal 89
Endothelium 42
B Epidermal cyst 85
Bacterial infections of retina 115 Epidermis 14
Benign lesions 32 Epithelial changes 47
Blood staining of cornea 41 Epithelial lacrimal gland tumors 91
Botryoid 89 Epithelial tumors 91
Burkitt’s lymphoma 90 Epithelium 26,37
Extension of melanoma 64
C Exudative changes 71
Capillary hemangioma 86 Eyeball specimens 4
Capsular alterations 47
Carcinoma in situ 31 F
Cavernous hemangioma 85
Fine needle aspiration
Chalazion 15
biopsy (FNAB) 103,108
Choristoma 84
Fixation 3
Coats’ disease 75
Fleurettes 59
Common primary sites 92
Flexner-Wintersteiner rosettes 59
Complications 105
Follicular lymphoma 90
Congenital tumors 84
Frozen section 109
Conjunctiva 10,98,106
Fungal 38
Conjunctival degenerations 29
Fungal infections of retina 115
Conjunctival dysplasia 31
Cornea 9,99
Corneal and conjunctival scraping 97 G
Corneal graft rejection 42 Granulomatous 52
Corneolimbal approach 104 Gross examination 4,56
Cortical cataract 49 Gross inspection of eyeball 5
Cystic lesions of eyelid 24 Grossing of other specimens 9
Cysts 29 Growth pattern 61
Cytopathologic correlation 98,106
Cytopathology of intraocular H
fluid/tissue specimen 107 Hamartoma 85
Cytopathology of eye 95 Handling of small biopsy specimens 11
Hemangiopericytoma 86
D Hemorrhagic changes 72
Degeneration 41 High power 58
Dermis 14 Histologic sections 12
Dermoid 26,85 Histology of lens 46
Descemet’s membrane 42 Histopathologic risk factors 60
Diabetic maculopathy 73 Histopathology 18,66
Diabetic retinopathy 70 Homer-Wright rosettes 59
Diagnostic possibilities and technique Homocystinuria 46
of choice 107 Hypermature cataract 49
130 MANUAL OF OCULAR PATHOLOGY

I O
Identification of side of globe 4 Ocular pathology in AIDS 113
Immunohistochemical staining 12 Ophthalmic pathology specimens 3
Impression cytology 96 Opportunistic infections of retina 114
Infections 38 Optic nerve
Inflammation 26 glioma 87
Inflammatory conditions 107 meningeal tumors 87
Internal description 6 meningioma 88
Interpretation 97,100,103 Orbit 108
Intraocular lymphoma 67 Orbital tissue 10
Intraocular tumors 55 Orbital cellulites 82
Invasive squamous cell carcinoma 31 Orbital FNAB 105
Orbital inflammation 82
K Orbital involvement 115
Keratoacanthoma 18 Orbital metastasis 92
Orbital tumors 84
L Other histologic features related to
Large cell lymphoma 91 prognosis 63
Layers of retina 70 Other pathologic features 59
Lens 10
P
Lens substance alterations 48
Pars plana transvitreal approach 103
Lid 10
Pathologic study 3
Lid lesions 15
Pathological classification 27
Low power 56
Pathology of
Lymphangioma 86
conjunctiva 25
Lymphoid tumors 32
cornea 35
eyelid 13
M
hair and glands of eyelid 21
Malignant lesions 32
lens 45
Malignant lymphoma 32,90 orbit 81
Malignant melanoma 23,34, 60,65 uvea 51
Marfan’s syndrome 46 Peripheral nerve tumors 87
Marginal zone lymphoma 90 Pigmentation 61
Measurement of globe 5 Pleomorphic 89
Medulloepithelioma 66 Poorly differentiated 58
Melanocytic tumors 33 Posterior segment lesions in aids 114
Melanomas of ciliary body 66 Preproliferative diabetic retinopathy 72
Melanotic tumors of eyelid 23 Preretinopathy 71
Metastatic tumors 66 Primary acquired melanosis (PAM) 33
Microscopic features 65 Primary orbital tumors 84
Molluscum contagiosum 16 Primary site of choroidal metastasis 66
Processing of biopsy specimen 3
N Processing of tissues includes 3
Neoplasms 107 Proliferative diabetic retinopathy 73
Neoplastic lesions 17 Protozoal (Acanthamoeba) 39
Neurogenic tumors 23 Protozoal infections of retina 115
New AFIP classification 62 Pseudo exfoliation syndrome 47
Noninfective vascular disorders 114 Pseudotumor 83
Nonneoplastic lesions 15 Pterygium and pinguecula 29
Nonproliferative retinopathy 71
Novel prognostic parameters R
in uveal melanoma 65 Reactive lymphoid hyperplasia 32
Nuclear sclerosis 48 Retina 114
 INDEX 131
Retinoblastoma 56 Treatment 90
Rhabdomyosarcoma 88 Tumor sample collection for molecular
Rosettes 59 biological studies 9
Tumors of lacrimal gland 91
S Types of presentation 22
Secondary glaucoma 108
Secondary orbital tumors 93 U
Sectioning of globe 6 Uveal tissue 10
Site of damage 71
Size of tumor vs prognosis 63 V
Small lymphocytic lymphoma 90 Vascular changes 71
Special procedures 8 Vascular tumors of eyelid 23
Special techniques 107 Vasculitis 83
Squamous cell carcinoma 20 Vasculogenic tumors 85
Squamous lesions 29 Verruca vulgaris 16
Squamous papilloma 30 Viral infections 16
Stains used in ocular pathology lab 10 Vitreous amyloidosis 78
Stevens-Johnson syndrome 27 Vitreous tap 102
Stroma 26,38 Vogt-Koyanagi-Harada (VKH)
Structures adherent to corneal surface 43 syndrome 52
Subretinal fnab 104
Sympathetic ophthalmia 52 W
Wegener’s granulomatosis 84
T Weill-Marchesani syndrome 46
Telepathology 117
Thyroid ophthalmopathy 83 Z
Transillumination 5 Zonular alterations 46