Refractive

Accommodative Esotropia
Gina M. Rogers, MD and Susannah Q. Longmuir, MD
January 26, 2011
Chief Complaint: Eye crossing
History of Present Illness: The patient is a 4-year-old boy who originally presented to an outside
ophthalmologist at 2 years of age after his parents noted that his eyes were crossing. The crossing
was first noted a few weeks prior to that visit. He was evaluated and placed in glasses, which
resulted in partial improvement of the crossing. Over the ensuing 2 years his prescription was
updated as needed by the outside provider. His mother seeks a second opinion to ensure that his
condition is being managed appropriately. The mother reports that the patient wears his glasses
well. She sees occasional crossing with the glasses on. He has never been patched. He is otherwise
healthy, growing and developing normally.
Past Medical History:
He was born full term by normal spontaneous vaginal delivery without complications.
Past Surgical History:
None
Family History:
No known strabismus or inherited eye disease
OCULAR EXAMINATION: AGE 2
Visual acuity without correction:
OD: 20/80

OS: 20/80

Pupils: Equally round and briskly reactive. No relative afferent pupillary defect.
Stereopsis testing: Unable to test
Strabismus exam: Alternate Cover Testing

Motility: Full OU

Esotropia (ET): 30 prism diopters in the distance

Esotropia (ET): 25 prism diopters at near

Cycloplegic refraction:
OD: +3.75 D sphere

OS: +3.50 D + 0.50 D x 090

Slit lamp exam: Within normal limits OU

Dilated fundus exam: Within normal limits OU

OCULAR EXAMINATION: AGE 4

Visual acuity with correction: HOTV

OD: 20/20

OS: 20/20

Pupils: Equally round and briskly reactive. No relative afferent pupillary defect.
Stereopsis testing:1

Titmus Fly: stereopsis present

Animals: 2/3 identified

Circles: 2/9 identified

Wearing spectacle prescription:

OD: +4.00 D sphere

OS: +3.25 D + 0.75 D x 100

Cycloplegic over-refraction:

OD: +0.50 D sphere

OS: +0.75 D sphere

Figure 1: Titmus Fly Test

Strabismus exam: Alternate Prism Cover Test

Without correction:
Right Gaze

Motility

Motility

Left Gaze

Upgaze: ET 30

ET 30

Distance: ET 30

ET 30

Downgaze: ET 30

Near: ET 50

With correction:
Right Gaze

Motility

Motility

Left Gaze

Distance:

Orthotropic

Near: Orthotropic

Please see http://webeye.ophth.uiowa.edu/eyeforum/tutorials/Bhola-BinocularVision.htm for a more in depth

discussion about binocular vision.

Figure 2: Gaze photos without correction

Figure 3: Comparison of alignment

without and with correction

General: Normal mood and behavior; no nystagmus or abnormal head position

Slit lamp exam: Normal OU
Dilated fundus exam: Normal macula, vessels and periphery OU. Cup to disc ratio 0.2 OU.
DIAGNOSIS: Refractive Accommodative Esotropia
DISCUSSION:
Accommodative esotropia is defined as the convergent deviation of the eyes associated with
activation of the accommodative reflex. It is classically divided into three categories:
1. Refractive accommodative esotropia (low accommodative convergence/accommodation or
AC/A ratio of less than 5),
2. Nonrefractive accommodative esotropia (high AC/A ratio), and
3. Partially accommodative esotropia.

Accommodative esotropia is the most common cause of childhood esotropia.

These esodeviations share common characteristics. All accommodative esodeviations are acquired
with onset generally between 6 months and 7 years of age, with average onset at 2.5 years of age.
Rare cases have been reported from age 3 months to 11 years old. At the onset, the deviation is
usually intermittent, but usually becomes constant in the following weeks to months. It is not
uncommon to obtain a history of illness, trauma or fatigue as a precipitating factor for the onset of
the deviation. There often is a family history of strabismus. Studies suggest that approximately 77%
of patients with accommodative esotropia have a first- or second-degree relative with the same
condition. Among first-degree relatives alone, the prevalence of accommodative esotropia is 23%;
therefore, it is important to have siblings examined. These esodeviations are frequently associated
with amblyopia (Hutchison 2004).
All children with new-onset esotropia require a thorough history, review of systems, and
comprehensive examination. The examination must include assessment of vision, ocular motility,
strabismus measurements at distance and near and cycloplegic refraction in addition to a general
ocular examination. Distance and near measurements are essential to determine the
accommodative convergence to accommodation (AC/A) ratio. The AC/A ratio should be
investigated if there is good alignment in the distance and greater than 10 prism diopters of
increased esodeviation at near in full correction. The next step is to relax accommodation and
determine the remaining amount of convergence. We typically hold +3.00 diopter lenses over both
eyes and remeasure the esodeviation at near. The esodeviation while looking through +3.00 D
lenses is subtracted from the original esodeviation at near without the +3.00 D lenses and the
difference is divided by +3.00. If the value is greater than 5, then the patient has a high AC/A ratio.
The treatment in this setting may include bifocals if they allow the patient to fuse.
Calculation of Accommodative Convergence/Accommodation (AC/A) ratio by the gradient method
(measurements with and without the additional lens are done at the same distance):
AC/A
ratio

Change in deviation
Change in lens power

(Esodeviation without additional lens esodeviation with lens)

Additional lens power

This case is an example of refractive accommodative esotropia with normal AC/A ratio (in proper
correction, the patient is orthophoric in the distance and at near). The mechanism of this type of
esodeviation involves 3 factors:
1. Uncorrected hyperopia,
2. Accommodative convergence, and
3. Insufficient fusional divergence
The uncorrected hyperopia forces the patient to exert excessive accommodation to focus images on
the retina, thus evoking increased convergence. If the patients fusional divergence mechanism is
insufficient to compensate the increased convergence, esotropia results. Generally, in refractive
accommodative esotropia, the deviation is between 20 and 30 prism diopters, the deviation is

similar in the distance and at near, and the average amount of hyperopia is +4 diopters (range
+3.00 to +10.00 diopters) (BCSC Pediatrics and Strabismus, 2007).
The goals of treating this condition are to restore normal ocular alignment, maintain good visual
acuity in each eye, and promote good binocular function. Treatment consists of prescribing
spectacle correction with the full amount of hyperopic correction as determined by cycloplegic
retinoscopy. Significant delay in the initial treatment following the onset of esotropia increases the
likelihood that a nonaccommodative component (partially accommodative esotropia) may develop
(Mulvihill et al 2000). Of course, if there is any concurrent amblyopia, treatment should be initiated
to address this issue.
To the ophthalmologist, the clinical diagnosis and treatment seems straightforward, but to the
parent or caretaker the condition may not be as easily understood. Many parents often request
surgery, thinking it will be a quick fix. For the typical refractive accommodative esotropia patient,
the treatment is glasses, not surgery. Strabismus surgery is indicated if optical correction is
ineffective in restoring normal ocular alignment. It is important for the eye care provider to take the
time to discuss the mechanism of the condition so that the childs caretaker can comprehend the
situation and fully cooperate with the treatment. The importance of full-time glasses wear and
amblyopia treatment, if applicable, cannot be over-emphasized. To prevent frustration or
misunderstanding, one should mention that the eyes will cross when the child is not wearing
glasses because glasses control the deviation and do not cure it. It is also important to convey to the
caretaker that this is a long-term condition that requires routine monitoring for amblyopia and that
changes in spectacle prescription may be required not only to maintain vision but also alignment.
Parents are also frequently concerned over their childs long-term prognosis. Although the childs
course cannot be predicted at the initial visit or even within years of initiating treatment, it is often
helpful to mention that some children can be weaned out of their glasses, while others will require
optical correction to maintain alignment throughout adulthood. Contact lenses and refractive
surgical procedures may be options as the child nears adulthood.
Differential diagnosis:
Cranial Nerve 6 palsy
Duanes syndrome
Basic, acute, and cyclic esotropia
Divergence insufficiency
Spasm of the near synkinetic reflex

SUMMARY

Most common type of childhood

strabismus
Prompt recognition and treatment
provides the most successful outcomes
Onset between 6 months and 7 years,
average 2.5 years
Deviation typically measures 20-30
prism diopters
Similar amount of esodeviation at
distance and near (normal AC/A ratio)
Average hyperopia of +4 diopters

SIGNS
Inward deviation of eye
Full motility
Improvement of ocular alignment in
proper glasses correction

SYMPTOMS

TREATMENT

Onset in childhood, crossing noted by

caretaker
Diplopia may occur in older children, but
will usually disappear as a suppression

scotoma develops in the deviating eye

Glasses with full amount of hyperopic

treatment as determined by cycloplegic
refraction

References:
Hutcheson KA. Childhood esotropia. Curr Opin Ophthalmol 2004;15(5):444-8.
"Refractive Accommodative Esotropia" in Chapter 7: Esodeviations. Basic and Clinical Science
Course: Section 6. Pediatric Ophthalmology and Strabismus. San Francisco: American Academy of
Ophthalmology, 2010-2011:93-95.
Mulvihill A, MacCann A, Flitcroft I, O'Keefe M. Outcome in refractive accommodative esotropia. Br J
Ophthalmol 2000;84(7):746-9.


Suggested Citation Format:
Rogers GM, Longmuir SQ. Refractive Accommodative Esotropia. EyeRounds.org. January 26, 2011;
Available from: http://EyeRounds.org/cases/129-accommodative-esotropia.htm