skull/facial

bones/sinuses/mandible/
Question Answer
A) dolichocephalic - 40' angle of
petrous pyramids B) mesocephalic -
name the three classi cations of the skull and describe the 47' angle of petrous pyramids C)
differences.
brachycephalic - 54' angle of petrous
pyramids
CR angles and degrees of rotation are based on _____ (average)
skull, which has an approximate angle of _____ between the mesocephalic 47'
midsagittal plane and the long axis of the petrous bone.
there is a _____ degree difference between the OML and IOML and
____ degrees between the OML and GAL 7-8' 7-8'
What is the positioning term for the lateral junction of the eyelid. Outer canthus
What is the positioning term for the posterior angle of the jaw. gonion
What is the positioning term for the line between the IOM and the
EAM? IOML - infraorbitomeatal line
What is the positioning term for what corresponds to the highest
"nuchal" line of the occipital bone? Inion - occipital protruberance
What is the positioning term for the line between the glabella and
glabelloalveolar line - GAL
the alveolar process of the maxilla?
What is the positioning term for the line between the mental point
MML - mentomeatal line
and the EAM?
What is the positioning term for what is located at the junction of
nasion
the two nasal bones and the frontal bone?
What is the positioning term for the small cartilaginous ap tragus
covering the ear opening?
What is the positioning term for what corresponds to the highest supraorbital groove
level of the facial bone mass?
What is the positioning term for the line between the midlateral OML - orbitomeatal line
orbital margin and the EAM?
What is the positioning term for the center point of the EAM? auricular point
What is the positioning term for the positioning line primarily LML - lips-meatal line
used for the modi ed Waters projection?
What is the positioning term for the line used to ensure skull is in IPL - interpupillary line
true lateral?
What is the positioning term for what corresponds to the level of TEA - top of ear attachment
the petrous ridge?
What is the positioning term for the smooth, slightly depressed glabella
area between the eyebrows?
What are the most common errors made during skull Tilt Rotation excessive exion
radiography? excessive extension incorrect CR angle
which two are the most common errors made during skull TILT and ROTATION
imaging?
Which imaging modality is the most common neuroimaging CT
procedure performed for the cranium?
Which imaging modality is commonly performed on neonates with Ultrasound
a possible intracranial hemorrhage?
Which imaging modality is commonly performed to evaluate nuclear medicine
patients for Alzheimer disease?
Describe a fracture that may produce an air- uid level in the
sphenoid sinus. basal skull fracture
describe a destructive lesion with irregular margins osteolytic neoplasm
Describe a ping-pong fracture. depressed skull fracture
Describe a proliferative bony lesion of increased density. osteoblastic neoplasm
Describe a tumor that may produce erosion of the sella turcica. pituitary adenoma
Describe another term for osteitis deformans. Paget's disease
Describe a bone tumor that originates in the bone marrow. multiple myeloma
Which of the following clinical indications may require an increase
in manual exposure factors? A) advanced Paget's disease B) A) advanced Paget's disease
metastatic neoplasm C) multiple myeloma D) basal skull fracture
Which cranial bone is best demonstrated with an AP Axial (Towne)
projection of the skull? occipital
When using a 30' caudad angle for the AP Axial (Towne)
projection, which positioning line should be perpendicular to the OML
IR?
A properly positioned AP Axial (Towne) projection should place foramen magnum
the dorsum sellae into the middle aspect of _____.
A lack of symmetry of the petrous ridges during an AP axial Rotation
(Towne) indicates what problem?
If the patient cannot ex the head adequately for the AP Axial Place the IOML perpendicular to the
(Towne), what can the tech do? IR and increase the CR angle to 37'
What evidence on an AP Axial (Towne) image indicates whether dorsum sellae and posterior clinoids
are visible centered within the
the correct CR angle and head exion were used? foramen magnum
What CR angle should be used for the PA Axial (Haas)? 25' cephalad
Where is the CR centered for a lateral projection of the skull? 2" superior to the EAM (5cm)
What is the speci c error if the mandibular rami are not ROTATION
superimposed on a lateral skull?
Where will the petrous ridges be projected with a 15' PA Axial in the lower 1/3 of the orbits
(Caldwell) projection of the cranium?
Which speci c positioning error is present if the petrous ridges excessive exion of the head or
are projected higher in the orbits than expected for a 15' PA Axial? insuf cient CR angle
Which projection of the cranium produces an image of the frontal 0' PA - posteroanterior skull
bone with little or no distortion?
For a patient with possible trauma, what must be determined rule out possible cervical fractures or
before performing the SMV skull? subluxation
What positioning error has been committed if the EAMs are not
superimposed with one more superior to the other on a lateral TILT
image?
Which skull positioning line is placed parallel to the plane of the IR
for SMV? IOML - infraorbitomeatal line
Which of the following projections best demonstrates the sella
turcica in pro le? lateral
Which projection best demonstrates the foramen rotundum? 25 - 30' PA Axial
Which of the following projections best demonstrates the clivus in C) Lateral
pro le? A) AP Axial B) 15' PA C) Lateral D) SMV
Where does the CR exit for a PA axial (Haas)? 1.5" superior to the nasion
Which imaging modality is best to differentiate between and CT
epidural and subdural hemorrhage?
An image of an AP Axial (Towne) skull shows the right petrous
ridge is wider than the left. Which speci c positioning error is rotation of the patient's face to the left
present?
An image of a 15' PA Axial (Caldwell) demonstrates the petrous excessive CR angle or excessive
ridges are projected at the inferior orbital margin. Which
positioning error led to this outcome? extension of the head
An image of 15' PA Axial (Caldwell) demonstrates the distance
between right midlateral orbital borders and lateral margin of the rotation of the patient's face to the left
skull cortex is greater than the left side. Which positioning error
led to this outcome?
An image of an SMV Skull shows the mandibular condyles are excessive exion, insuf cient
within the petrous bone. Which speci c positioning error led to extension or CR not perpendicular to
the this problem? IOML/IR
An image of a lateral Skull shows orbital plates are not
superimposed (one is slightly superior). What is the positioning tilt
error?
A lateral skull image demonstrates one mandibular ramus about rotation
.5cm more anterior than the other. What is the positioning error?
An AP axial (Towne) for skull demonstrates the dorsum sellae excessive extension of the skull or CR
projected above the foramen magnum. What is the positioning angle < 30' OML or 37' IOML
error?
A patient comes to XRay with a possible tumor of the pituitary
gland. Which projection would best demonstrate the bony lateral skull with collimation
involvement of the sella turcica?
A patient with possible linear fracture of right parietal bone right lateral skull
comes to ED. Which single x-ray best demonstrates this fracture?
A patient comes for a skull series, but cannot assume best position
for either version of AP Axial (Towne) because of a very short neck should perform the PA version (Haas)
and severe kyphosis. What can tech do to demonstrate the
occipital bone?
A patient with a possible basal skull fracture enters the Dorsal decubitus (think trauma -
emergency room. No CT is available. Which speci c position may supine lateral) will demonstrate the
provide xray evidence of this fracture? air/ uid levels in the sphenoid sinus
A neonate has a clinical history of craniosynostosis. Because of
the age of the patient, Dr doesn't order an xray. What other ultrasound
imaging modality can be performed for this condition?
A patient with a clinical history of acoustic neuroma comes to x- MRI or CT
ray. Which imaging modality can be performed for this pathology?
An image of an AP Axial (Towne) projection shows the posterior
arch of C1 is projected within the foramen magnum. The dorsum excessive exion of the neck or
sellae is projected on the posterior arch as well. What is the overangulation of the CR
positioning error?
Nothing - the image is for the
An image of the AP Axial (Towne) for cranium shows the mid-to CRANIUM and because the mandible
lower mandible is clipped. What should the tech do? is elongated due to the CR angle,
doesn't need to be included.
TRUE/FALSE Facial bone studies should always be performed FALSE - erect preferred
recumbent when possible.
TRUE/FALSE The common basic PA axial projection for the facial
bones requires a 15' caudal angle, which projects the dense TRUE
petrous pyramids into the lower 1/3 of the orbit.
TRUE/FALSE An increase in kV of 25-30% (with manual FALSE - a decrease is required due to
techniques) is often required for the geriatric patient with bone loss
advanced osteoporosis.
TRUE/FALSE CT is ideal for facial bone studies because it allows TRUE
for visualization of bony structures as well as related soft tissue of
facial bones.
TRUE/FALSE Nuclear med is not helpful in diagnosing occult facial FALSE Nuclear med is used for this
bone fractures.
FALSE Patient must be cleared of all
TRUE/FALSE MRI is an excellent imaging modality for detection of metallic foreign bodies before going to
small metal foreign bodies in the eye. MRI
What is the name of the fracture that results from a direct blow to Blow-out fracture
the orbit leading to disruption of the inferior orbital margin?
A free oating zygomatic bone is the frequent result of a _____ Tripod fracture
fracture.
What is the major disadvantage of performing a straight PA Dense petrous pyramids superimpose
projection for facial bones, with no CR angulation or neck facial bone structures, such as orbits,
extension, as compared with other facial bone projections? obscuring details
Where is the CR centered for a lateral position for the facial Zygoma
bones?
What is the proper name method for the parietoacanthial Waters method
projection of the facial bones?
Which facial bone structures are best seen with a parietoacanthial orbits
nasal
including infraorbital rims, bony
septum, maxillae, zygomatic
projection? bones, and arches
What CR angle must be used to project the petrous pyramids just 30' caudad
below the orbital oor with the PA Axial (Caldwell)?
Which structures speci cally are better visualized on the modi ed a less distorted view of the orbital rims
parietoacanthial (Waters) projection as compared with the basic Orbital rims/ oors
Waters projection?
- (OID) less magni cation/distortion
Give two reasons why projections of the facial bones are because bones are close to IR. -
performed PA rather than AP when possible. (ALARA) reduces patient dose to
thyroid/facial structures (eyes)
- centering (zygoma for FB, 2" superior
What are two differences between the lateral projections of the to EAM for cranium) - IR is placed
cranium and lateral projection for the facial bones? portrait for facial bones, crosswise for
cranium
The PA Waters for facial bones has the _____ line perpendicular to
the IR, which places the OML at _____ angle to tabletop/IR? MML 37'
Where does the CR exit for a parietoacanthial (Waters) facial acanthion
bones?
Where does the CR exit for a 15' PA axial (Caldwell) facial bones? nasion
The modi ed PA (waters) requires the _____ line is perpendicular to
the IR, which places the OML at a _____ angle to tabletop and LML - lips-meatal line 55'
image receptor.
TRUE/FALSE Lateral projections for the nasal bones are generally TRUE
taken bilaterally for comparison.
TRUE/FALSE The oblique inferosuperior (tangential) projections
for the zygomatic arch requires the skull be rotated and tilted 15' FALSE must be TOWARD affected side
away from affected side.
TRUE/FALSE Both oblique inferosuperior (tangential) projections TRUE
for the zygomatic arch are taken for comparison.
For a PA Waters, the petrous ridges should be projected directly
below the _____; and projected into the lower half of the maxillary maxillary sinuses infraorbital rims
sinuses or below the _____ for a modi ed Waters projection.
Which speci c facial bone structures (other than the mandible) zygomatic arches
are best demonstrated with SMV if correct exposure factors are
used (soft tissue technique)
Where is the CR centered for an AP axial for the zygomatic 1" superior to nasion
arches?
List the proper method name and common descriptive name for Rhese three point landing (cheek,
the parieto-orbital oblique projection for the optic foramen. nose, chin)
What is the nal angle of the midsagittal plane and the IR for the 53' in the lower outer quadrant of the
Rhese? Where is the optic foramina visible in the nal image? orbit
Which projection best demonstrates fractures of the orbital oors Modi ed Waters
(blowout fractures)?
Which projection best demonstrates the optic foramen? parieto-orbital oblique (Rhese)
Which projection best demonstrates a view of the single oblique inferosuperior projection
zygomatic arch?
Which projection best demonstrates pro le image of nasal bones
and nasal septum? lateral (nasal bones)
Which projection best demonstrates bilateral zygomatic arches? submentovertical (SMV)
Which projection best demonstrates the inferior orbital rim, parietoacanthial projection
maxillae, nasal septum, nasal spine, zygomatic bone and arches?
TRUE/FALSE The PA Axial of the mandible produces an elongated TRUE
view of the condyloid process.
Which projection of the mandible projects the opposite half of the axiolateral oblique
mandible away from the side of interest?
What must be done to prevent the ramus of the mandible from
being superimposed over the cervical spine with an axiolateral extend the neck/chin slightly
oblique projection of the mandible?
How much skull rotation from lateral toward IR is required with 30'
an axiolateral oblique projection of the body of the mandible?
How much skull rotation from lateral toward IR is required with 45'
an axiolateral oblique projection of the mentum of the mandible?
How much skull rotation from lateral toward IR is required with 0' - true lateral
an axiolateral oblique projection of the ramus of the mandible?
How much skull rotation from lateral toward IR is required with
an axiolateral oblique projection of the general survey of the 10-15'
mandible?
What is the maximum angle of the CR for an axiolateral oblique 25' cephalad
projection of the mandible?
What speci c positioning error has been committed if both sides insuf cient cephalic CR angle or skull
of the mandible are superimposed with an axiolateral oblique
projection? tilt
Where should the CR exit for a PA axial projection of the acanthion or lips (PA projection)
mandible?
Which cranial positioning line is placed perpendicular to the IR for
a PA or PA axial projection of the mandible? OML
TRUE/FALSE For a true PA of the mandibular body, the AML TRUE
should be perpendicular to the IR.
TRUE/FALSE the CR should be angled 20-25' caudad for a PA axial FALSE cephalad
of the mandible.
Which aspect of the mandible is best demonstrated with an AP condyloid process
axial projection?
What CR angle is required for AP axial of the mandible if OML is
perpendicular to IR? What angle is required if the IOML is 35' caudad or 42' caudad
perpendicular?
Where is the CR centered for an AP Axial projection of the 1" superior to the glabella
mandible?
Which projection of the mandible demonstrates the entire SMV
mandible, including the coronoid and condyloid processes?
Which imaging system provides a single, frontal perspective of the orthopantomography (panoramic
entire mandible? tomography)
What device provides inherent collimation during an narrow, vertical slit diaphragm
orthopantomographic procedure?
Which cranial line is placed parallel to the oor for the IOML
orthopantomography of the mandible?
What type of image receptor must be used with analog curved, non-grid 9x12 IR
orthopantomography?
TRUE/FALSE The modi ed Law method provides a bilateral and TRUE
functional study of the TMJ.
TRUE/FALSE The mandibular condyles move anteriorly as the TRUE
mouth is opened.
Which projection of the TMJ requires the skull be kept in true Schuller axiolateral projection TMJ
lateral position?
The axiolateral (Schuller) projection for TMJ requires a CR angle 25 - 30' caudad
of _____ and which direction _____?
The axiolateral oblique TMJ is commonly referred to as the _____ modi ed Law 15' (oblique) 15'
method, which requires a _____ degree head rotation from lateral (caudad)
and a _____ degree caudad angle.
If the area of interest is the temporomandibular fossae, angle the
CR _____ to the OML for AP Axial (towne) to reduce 40' caudad
superimposition of the TM fossae and mastoid portions of the
temporal bone.
Aligning the _____ plane perpendicular to the IR prevents rotation GAL/ MSP
of either a PA or an AP axial mandible.
What digital kV should be should used for sinus radiography? 75-85 kV
To demonstrate any possible air or uid levels within the sinuses, perform erect if possible use a
it is important to _____ and _____ horizontal beam
TRUE/FALSE Secondary osteomyelitis is often caused by tumor
invasion. FALSE
TRUE/FALSE Ultrasound exams of the maxillary sinuses to rule TRUE
out sinusitis are possible.
TRUE/FALSE MRI is the preferred modality to study soft tissue TRUE
changes and masses within the sinuses.
List the four most commonly performed routine projections for Parietoacanthial Waters Lateral FB PA
paranasal sinuses. axial Caldwell SMV
Which single projection for a paranasal sinus routine provides and
image of all four sinus groups? Lateral
If the patient cannot stand/sit for the lateral paranasal sinuses horizontal beam
exam, the projection should be taken with _____.
Which paranasal sinuses are best demonstrated with a PA frontal and anterior ethmoid
Caldwell projection?
To avoid angling the CR for erect PA axial Caldwell sinus, the head
should be adjusted so that the OML is _____ degrees from 15'
horizontal.
Which group of paranasal sinuses is best demonstrated with a
parietoacanthial projection? The OML forms a _____ angle with the maxillary 37'
IR.
Which positioning line is placed perpendicular to the IR for a MML
parietoacanthial projection?
Where are the petrous ridges located on a well-positioned just below the maxillary sinuses
parietoacanthial projection?
Which paranasal sinuses are demonstrated with an SMV sphenoid, ethmoid, and maxillary
projection of the paranasal sinuses? sinuses
Where should the CR exit for both the parietoacanthial Waters
and PA transoral (open-mouth Waters)? acanthion
What is the one major difference in positioning between the opening the mouth for the PA axial
parietoacanthial and PA axial transoral projections? transoral
Which sinuses are projected through the oral cavity with the PA sphenoid
axial transoral projection?
What anatomy does the lateral sinus projection best
demonstrate? all four paranasal sinuses
What anatomy does the parietoacanthial sinus projection best
demonstrate? best view of maxillary sinuses
What anatomy does the PA axial Caldwell sinus projection best frontal and anterior ethmoid
demonstrate?
What anatomy does the PA transoral sinus projection best sphenoid sinus in oral cavity
demonstrate?
inferosuperior view of sphenoid and
What anatomy does the SMV sinus projection best demonstrate? ethmoid sinus
An image of a lateral facial bones shows the mandibular rami are
not superimposed. What positioning error led to this error? rotation

An image of a parietoacanthial Waters shows the petrous ridges NO, not acceptable ensure the MML is
are projected within the maxillary sinuses. Is this acceptable? If perpendicular to the IR (insuf cient
not, what must be done to correct? extension) and that CR is
perpendicular to exit at acanthion
An image of a PA Waters shows the distance between the lateral
margins of the orbits and the lateral aspect of the cranial cortex is rotation
not equal. What type of positioning error is this?
An image of a 30' PA axial projection facial bones shows the
petrous ridges are projected at the level of the infraorbital
Yes, this is acceptable
margins. Is this acceptable? If not, what must be done to improve
the next image?
An image of a superoinferior projection of the nasal bones shows
the glabella is superimposed over the nasal bones. What excessive exion incorrect CR
positioning error led to this outcome? How does the tech correct angulation
it?
A lateral image of the facial bones demonstrates the bodies of the
mandibles are not superimposed. One is about 1cm superior to Tilt ensure the GAL is parallel to the IR.
the other. How to correct?
A parieto-orbital oblique (Rhese) shows the optic foramen is NO, not acceptable increase extension
located in the upper outer quadrant of the orbit. Is this of head/neck
acceptable? how to x?
An image of an axiolateral oblique mandible shows the body of the insuf cient rotation of the skull
mandible is severely foreshortened, although it is the area of
interest. What positioning error led to this outcome? towards the IR
A patient with a possible fracture of the nasal bones enters the ER.
Dr is concerned about deviation of the bony nasal septum along R and L Lateral Nasal bones
with possible fractures. What routine would be best? parietoacanthial Waters
A possible blowout fracture of the right orbit enters the ER. In parietoacanthial axial (modi ed
addition to the normal FB routine, what single projection would Waters)
best demonstrate this type of injury?
A patient w/possible fracture of left zygomatic arch comes in. Oblique inferosuperior (tangential);
Neither the AP axial nor the SMV demonstrates left side well. bilateral projections for comparison
Radiologist is indecisive as to whether arch is fractured. What
other projections can the tech provide to better de ne this area?
Tech attempts to perform an SMV for zygomatic arches but
place CR perpendicular to IOML, then
because of the size of the patient's shoulders, the patient cannot angle IR to be perpendicular to CR and
ex his neck enough to place IOML parallel to IR. What can tech IOML
do to work around this?
PA Caldwell sinus image shows petrous pyramids are projected
into lower half of orbits, obscuring the ethmoid sinuses. Tech uses extend head/neck more to move the
a horizontal beam for these projections. Skull was positioned petrous pyramids down
placing OML 15' angle from horizontal plane. How x?
an image of a parietoacanthial projection shows the distance
between the MSP and outer orbital margin is not equal. What rotation
positioning error?
an image of an SMV sinus shows the distance between the
mandibular condyles and lateral border of the skull is not equal. tilt
What positioning error?
A PA transoral image shows the sphenoid sinus is superimposed increase extension of head/neck (MML
over the upper teeth and nasal cavity. How adjust position to x? must be perpendicular)
In a PA Waters, the petrous ridges are projected below the
maxillary sinuses. What positioning error (if any) is present? nothing is wrong
A patient with a clinical history of sinusitis comes for a sinus study.
The patient is quadriplegic and cannot be placed erect. Which horizontal beam lateral
single projection demonstrates any possible air uid levels in the
sinuses?
Need to rule out a possible polyp in the sphenoid sinus. What Lateral PA Caldwell parietoacanthial
routine or special projection provides the best assessment for this
patient? SMV PA transoral
patient with clinical history of deviated bony nasal septum. Which
facial bone projections best demonstrate the degree of deviation? PA PA axial parietoacanthial Waters