General oto imaging Flashcards
A cervical spine X-ray revealing a greater than 5-
mm widening of the predentate space (between
the anterior surface of the dens and the posterior
surface of the C1 tubercle) is worrisome for what
traumatic injury?
Atlantoaxial dissociation
Conventional radiography of the facial bones and
neck has been largely replaced by computed
tomography (CT). What traditional views were
used to view the following:
● Frontal, maxillary, and sphenoid sinus
● Frontal sinuses, posterior ethmoid air cells,
orbital floors
● Maxillary sinuses, anterior ethmoid air cells,
orbital floors
● Sphenoid sinuses, anterior and posterior walls
of the frontal sinuses
● Soft tissue of the neck
● Lateral view (5 degrees off true lateral)
● Caldwell view (15 degrees off caudal angulation)
● Waters view (neck in 33 degrees of extension)
● Submentovertex view (anteroposterior [AP] projection,
head in 90 degrees of extension)
● AP and lateral views
In a stable pediatric patient with stridor, what
radiography is appropriate?
AP and lateral neck films to evaluate for retropharyngeal
abscess, croup, epiglottitis, and radiopaque foreign body
What are the most common findings on chest radiography in a patient with a witnessed foreign-
body aspiration and clinical signs suggestive of
aspiration?
Mediastinal shift, unilateral hyperinflation, atelectasis, and a
foreign object if radiopaque
Although they have been largely replaced by CT
scan, radiographs of the temporal bone are
occasionally necessary. Name the following views:
● Lateral view of the mastoid with 30 degrees of
cephalocaudad angulation
● View of the petrous apex with patient facing the
film, head slightly flexed and turned 45 degrees
opposite the film
● Comparison of both mastoid bones and petrous
pyramids via AP view with a 30-degree tilt
● Schüller view
● Stenvers view
● Towne view
Why is a CT scan typically a more appropriate
imaging study in evaluating patients with a
potential deep neck space infection instead of
magnetic resonance imaging (MRI)?
Although MRI provides better soft tissue definition, it is
expensive and requires a lengthy scan time compared with
CT and therefore may necessitate sedation of a child or a
distressed patient and increase the likelihood of airway
compromise.
On T1-weighted MRI, contrast-enhancing tumors may be hidden by surrounding fat. What techni-
que can be used to achieve better visualization of the tumor?
Fat suppression
Describe the T1-weighted appearance of water
and fat on MRI.
Low intensity and high intensity, respectively
What are some of the contraindications to MRI
use?
Electromagnetic force can cause serious malfunction to
cardiac pacemakers and cochlear implants (although new
techniques have been developed that allow cochlear
implant recipients the ability to have MRI studies). Some
older vascular clips and ossicular prostheses contain para-
magnetic components, and unless these are known to be
MRI compatible, another modality should be used.
What does SUV stand for in regard to positron emission tomography (PET) imaging?
Standardized uptake value, which provides a semiquantita-
tive index of radio tracer uptake
What does the presence of an echogenic (fatty) hilum typically indicate during ultrasound exami-
nation of the neck?
Benign disease. Normal lymph nodes have an echogenic
hilum, whereas it is reported that there is an absent hilum
in 96 of metastatic lymph nodes.
Can the location of normal parathyroid glands be
identified on ultrasound examination of the
thyroid and neck?
Normal parathyroid glands are not usually visible because of
their small size and similar echo texture to adjacent thyroid
tissue.
What is acoustic shadowing in ultrasound imaging?
Diminished sound or loss of sound posterior to a strongly
reflecting or attenuating structure
