CT final exam questions with correct answers
With the preprogrammed protocols (pre-selected kV, mAs, and pitch), the technologist will only have to adjust
the _____________ and ______________ - VERIFIED ANSWER✔✔-scan range, field of view
Most CT scans consist of a minimum of ____ scans - VERIFIED ANSWER✔✔-2
It is important that the operator inputs the proper patient data and patient ______________ on the table so that the
software can properly annotate images - VERIFIED ANSWER✔✔-patient position
Positioning aids for the head include a ____________ or a molded ________________ - VERIFIED
ANSWER✔✔-head holder, molded head sponge
In head CT, slice angle is determined by _________________ or by _______________ the gantry - VERIFIED
ANSWER✔✔-head position (chin up or down), tilting
Some modern systems do not allow ______________ of the gantry - VERIFIED ANSWER✔✔-tilting
the primary modality for imaging the head in emergent situations - VERIFIED ANSWER✔✔-Non-contrast CT
Because of the greater difference in beam attenuation ability of dense bone and brain tissue,
___________________ can appear - VERIFIED ANSWER✔✔-streak artifacts
To decrease the chance of streak artifacts in head CT you can ________________ slice thickness and
________________ kVp - VERIFIED ANSWER✔✔-decrease, increase
Unlike regular soft tissue, the window for the brain is super _____________________ , due to similarities in
density of tissues - VERIFIED ANSWER✔✔-narrow
the two most common windows used when imaging the head - VERIFIED ANSWER✔✔-brain window & bone
window
brain windows are ____________ while bone windows are ______________ - VERIFIED ANSWER✔✔-
narrow, wide
common CTs of the head (5) - VERIFIED ANSWER✔✔-1. routine head (no contrast)
2. head with contrast
3. sinuses
4. facial bones
5. IACs (internal auditory canals)
topogram/scout image in routine head CT - VERIFIED ANSWER✔✔-lateral (entire head)
In routine head CT you use the _______________ line as a reference to scan parallel to, because it reduces
exposure to the eyes - VERIFIED ANSWER✔✔-supra-orbital meatal line (SOML)
scan range of routine head CT: - VERIFIED ANSWER✔✔-base of skull to vertex
the posterior fossa protocol changes _____________ and _______ for acquisition through the base of the skull
What is the slice thickness for the posterior fossa? - VERIFIED ANSWER✔✔-slice thickness, kVp
1.25mm
Enhanced head CT (contrast head CT) is indicated for suspected neoplasms, ________________ , or vascular
,__________________ - VERIFIED ANSWER✔✔-inflammation, abnormalities
contrast enhances the attenuation of _________ matter in the brain - VERIFIED ANSWER✔✔-grey
contrast media permits the differentiation of _____________ from _____________ structures in the brain -
VERIFIED ANSWER✔✔-vascular, nonvascular
scan times for the brain are not as _____________ as other areas of the body; and delays up to _____ minutes
may maximize sensitivity - VERIFIED ANSWER✔✔-critical, 5
_______% to _______% of head CTs require contrast, however, it is not common practice to do so anymore -
VERIFIED ANSWER✔✔-50 to 90%
usually, initial head scans are done without _____________ and if indicated, proceeded by alternate imaging
modalities, such as __________ - VERIFIED ANSWER✔✔-contrast, MRI
IACs and temporal bone scans are indicated for cholesteatoma, fractures, ______________ and
_________________ - VERIFIED ANSWER✔✔-hearing loss, acoustic neuroma
scout/topogram for IACs/temporal bones - VERIFIED ANSWER✔✔-AP and a lateral of entire head
Temporal bones and IACs require _______ resolution imaging - _________ slices, ________ DFOV and high-
resolution reconstruction algorithm - VERIFIED ANSWER✔✔-high, thin, small
For temporal bones and IACs, the scan starts at the bottom of the _____________________ and extends to the top
of the _______________ (below the mastoid process to above the petrous ridge) - VERIFIED ANSWER✔✔-
temporal bones, external ear
temporal bones and IAC scans are always performed _______________________ - VERIFIED ANSWER✔✔-
bi-laterally
because the slice thickness for temporal bones and IAC is so thin, it is very important the patient remain
_________________ - VERIFIED ANSWER✔✔-motion free
temporal/IAC scans are usually (enhanced/unenhanced) but if they are, they use the same volume as head CT and
are scanned in ____________________ phase - VERIFIED ANSWER✔✔-unenhanced, venous
TMJs are scanned in both __________ and ___________ planes, bilaterally - VERIFIED ANSWER✔✔-axial
and coronal
when scanning temporal/IACs it is important that the head is not _____________ or ______________ (must be
symmetric for comparison) - VERIFIED ANSWER✔✔-tilted, rotated
scout image for orbits: - VERIFIED ANSWER✔✔-lateral of entire head
in axial images of the orbits are scanned ___________ to the IOML - VERIFIED ANSWER✔✔-parallel
orbits: scan starts at the bottom of the __________ and ends above the ____________ - VERIFIED
ANSWER✔✔-orbit, orbit
orbit images are usually reconstructed into _____________ and _______________ images - VERIFIED
ANSWER✔✔-coronal, sagittal
when assessing the orbits, a bone window will identify _________________ , while a soft tissue window will
identify ____________ or _____________ - VERIFIED ANSWER✔✔-fractures, tumors or infection
the scan range for the orbits does not need to include the entire ____________ - VERIFIED ANSWER✔✔-skull
, topogram/scout for facial bones: - VERIFIED ANSWER✔✔-lateral
how should the head be positioned for a scout of the facial bones? what line should be perpendicular to the floor?
- VERIFIED ANSWER✔✔-tilting chin down (tucking chin) so that the IOML perpendicular to floor
usually both __________ and ______________ windows are used for facial bones - VERIFIED ANSWER✔✔-
bone, soft tissue
non-contrast CT (unenhanced) imaging of facial bones is used to characterize _____________ and
_______________ tissue injury - VERIFIED ANSWER✔✔-fractures, soft tissue
contrast CT (enhanced) imaging of facial bones is used for suspected _____________ and ________________ -
VERIFIED ANSWER✔✔-neoplasms, infection
scout of sinuses: - VERIFIED ANSWER✔✔-lateral of entire head
patient positioning for sinus scout image (hint: same as facial bones) - VERIFIED ANSWER✔✔-chin tucked
with IOML perpendicular to the floor
for sinuses, axial/helical images are scanned _____________ to the hard palate - VERIFIED ANSWER✔✔-
parallel
sinuses are scanned from the superior border of the ____________ sinuses, through the hard palate, and
posteriorly to include the _____________ sinuses - VERIFIED ANSWER✔✔-frontal, sphenoid
for sinuses, _____________ and _____________ windows are used - VERIFIED ANSWER✔✔-bone, soft tissue
unenhanced CT imaging is used when imaging the sinuses for recurrent or __________ sinusitis - VERIFIED
ANSWER✔✔-chronic
Enhanced CT is used in sinus imaging for suspected ______________ - VERIFIED ANSWER✔✔-neoplasms
the scan field for sinuses is the same as facial bones, without the ________ - VERIFIED ANSWER✔✔-chin/jaw
_________________ are the most common type of CT for the neck - VERIFIED ANSWER✔✔-soft tissue necks
for soft tissue neck images are taken to include the entire oro- and nasopharynx, mouth, throat, to the
________________ - VERIFIED ANSWER✔✔-top of lungs
Dentures, appliances, earrings, chains and hearing aids must be removed to prevent _____________________ -
VERIFIED ANSWER✔✔-streak artifacts
for soft tissue neck imaging, the patient is positioned ______________ , and arms relaxed ________________ at
the patients side to prevent artifact from shoulders - VERIFIED ANSWER✔✔-supine, caudally
performing soft tissue neck exams without contrast is __________ - VERIFIED ANSWER✔✔-rare
soft tissue neck exams without contrast are usually only done when the patient cant tolerate contrast media, or if
they are looking at a _____________ injury - VERIFIED ANSWER✔✔-bone injury (c-spine)
axial soft tissue neck scans include from the ___________ orbit to include the entire maxillary sinus, to the lung
__________ (~sternal notch or lower) - VERIFIED ANSWER✔✔-mid (sometimes superior), apex
scout for soft tissue neck: - VERIFIED ANSWER✔✔-lateral (sometimes AP as well)
the lateral soft tissue neck scout image must include from the ______________ to the _________________ heads
- VERIFIED ANSWER✔✔-orbits, clavicular
With the preprogrammed protocols (pre-selected kV, mAs, and pitch), the technologist will only have to adjust
the _____________ and ______________ - VERIFIED ANSWER✔✔-scan range, field of view
Most CT scans consist of a minimum of ____ scans - VERIFIED ANSWER✔✔-2
It is important that the operator inputs the proper patient data and patient ______________ on the table so that the
software can properly annotate images - VERIFIED ANSWER✔✔-patient position
Positioning aids for the head include a ____________ or a molded ________________ - VERIFIED
ANSWER✔✔-head holder, molded head sponge
In head CT, slice angle is determined by _________________ or by _______________ the gantry - VERIFIED
ANSWER✔✔-head position (chin up or down), tilting
Some modern systems do not allow ______________ of the gantry - VERIFIED ANSWER✔✔-tilting
the primary modality for imaging the head in emergent situations - VERIFIED ANSWER✔✔-Non-contrast CT
Because of the greater difference in beam attenuation ability of dense bone and brain tissue,
___________________ can appear - VERIFIED ANSWER✔✔-streak artifacts
To decrease the chance of streak artifacts in head CT you can ________________ slice thickness and
________________ kVp - VERIFIED ANSWER✔✔-decrease, increase
Unlike regular soft tissue, the window for the brain is super _____________________ , due to similarities in
density of tissues - VERIFIED ANSWER✔✔-narrow
the two most common windows used when imaging the head - VERIFIED ANSWER✔✔-brain window & bone
window
brain windows are ____________ while bone windows are ______________ - VERIFIED ANSWER✔✔-
narrow, wide
common CTs of the head (5) - VERIFIED ANSWER✔✔-1. routine head (no contrast)
2. head with contrast
3. sinuses
4. facial bones
5. IACs (internal auditory canals)
topogram/scout image in routine head CT - VERIFIED ANSWER✔✔-lateral (entire head)
In routine head CT you use the _______________ line as a reference to scan parallel to, because it reduces
exposure to the eyes - VERIFIED ANSWER✔✔-supra-orbital meatal line (SOML)
scan range of routine head CT: - VERIFIED ANSWER✔✔-base of skull to vertex
the posterior fossa protocol changes _____________ and _______ for acquisition through the base of the skull
What is the slice thickness for the posterior fossa? - VERIFIED ANSWER✔✔-slice thickness, kVp
1.25mm
Enhanced head CT (contrast head CT) is indicated for suspected neoplasms, ________________ , or vascular
,__________________ - VERIFIED ANSWER✔✔-inflammation, abnormalities
contrast enhances the attenuation of _________ matter in the brain - VERIFIED ANSWER✔✔-grey
contrast media permits the differentiation of _____________ from _____________ structures in the brain -
VERIFIED ANSWER✔✔-vascular, nonvascular
scan times for the brain are not as _____________ as other areas of the body; and delays up to _____ minutes
may maximize sensitivity - VERIFIED ANSWER✔✔-critical, 5
_______% to _______% of head CTs require contrast, however, it is not common practice to do so anymore -
VERIFIED ANSWER✔✔-50 to 90%
usually, initial head scans are done without _____________ and if indicated, proceeded by alternate imaging
modalities, such as __________ - VERIFIED ANSWER✔✔-contrast, MRI
IACs and temporal bone scans are indicated for cholesteatoma, fractures, ______________ and
_________________ - VERIFIED ANSWER✔✔-hearing loss, acoustic neuroma
scout/topogram for IACs/temporal bones - VERIFIED ANSWER✔✔-AP and a lateral of entire head
Temporal bones and IACs require _______ resolution imaging - _________ slices, ________ DFOV and high-
resolution reconstruction algorithm - VERIFIED ANSWER✔✔-high, thin, small
For temporal bones and IACs, the scan starts at the bottom of the _____________________ and extends to the top
of the _______________ (below the mastoid process to above the petrous ridge) - VERIFIED ANSWER✔✔-
temporal bones, external ear
temporal bones and IAC scans are always performed _______________________ - VERIFIED ANSWER✔✔-
bi-laterally
because the slice thickness for temporal bones and IAC is so thin, it is very important the patient remain
_________________ - VERIFIED ANSWER✔✔-motion free
temporal/IAC scans are usually (enhanced/unenhanced) but if they are, they use the same volume as head CT and
are scanned in ____________________ phase - VERIFIED ANSWER✔✔-unenhanced, venous
TMJs are scanned in both __________ and ___________ planes, bilaterally - VERIFIED ANSWER✔✔-axial
and coronal
when scanning temporal/IACs it is important that the head is not _____________ or ______________ (must be
symmetric for comparison) - VERIFIED ANSWER✔✔-tilted, rotated
scout image for orbits: - VERIFIED ANSWER✔✔-lateral of entire head
in axial images of the orbits are scanned ___________ to the IOML - VERIFIED ANSWER✔✔-parallel
orbits: scan starts at the bottom of the __________ and ends above the ____________ - VERIFIED
ANSWER✔✔-orbit, orbit
orbit images are usually reconstructed into _____________ and _______________ images - VERIFIED
ANSWER✔✔-coronal, sagittal
when assessing the orbits, a bone window will identify _________________ , while a soft tissue window will
identify ____________ or _____________ - VERIFIED ANSWER✔✔-fractures, tumors or infection
the scan range for the orbits does not need to include the entire ____________ - VERIFIED ANSWER✔✔-skull
, topogram/scout for facial bones: - VERIFIED ANSWER✔✔-lateral
how should the head be positioned for a scout of the facial bones? what line should be perpendicular to the floor?
- VERIFIED ANSWER✔✔-tilting chin down (tucking chin) so that the IOML perpendicular to floor
usually both __________ and ______________ windows are used for facial bones - VERIFIED ANSWER✔✔-
bone, soft tissue
non-contrast CT (unenhanced) imaging of facial bones is used to characterize _____________ and
_______________ tissue injury - VERIFIED ANSWER✔✔-fractures, soft tissue
contrast CT (enhanced) imaging of facial bones is used for suspected _____________ and ________________ -
VERIFIED ANSWER✔✔-neoplasms, infection
scout of sinuses: - VERIFIED ANSWER✔✔-lateral of entire head
patient positioning for sinus scout image (hint: same as facial bones) - VERIFIED ANSWER✔✔-chin tucked
with IOML perpendicular to the floor
for sinuses, axial/helical images are scanned _____________ to the hard palate - VERIFIED ANSWER✔✔-
parallel
sinuses are scanned from the superior border of the ____________ sinuses, through the hard palate, and
posteriorly to include the _____________ sinuses - VERIFIED ANSWER✔✔-frontal, sphenoid
for sinuses, _____________ and _____________ windows are used - VERIFIED ANSWER✔✔-bone, soft tissue
unenhanced CT imaging is used when imaging the sinuses for recurrent or __________ sinusitis - VERIFIED
ANSWER✔✔-chronic
Enhanced CT is used in sinus imaging for suspected ______________ - VERIFIED ANSWER✔✔-neoplasms
the scan field for sinuses is the same as facial bones, without the ________ - VERIFIED ANSWER✔✔-chin/jaw
_________________ are the most common type of CT for the neck - VERIFIED ANSWER✔✔-soft tissue necks
for soft tissue neck images are taken to include the entire oro- and nasopharynx, mouth, throat, to the
________________ - VERIFIED ANSWER✔✔-top of lungs
Dentures, appliances, earrings, chains and hearing aids must be removed to prevent _____________________ -
VERIFIED ANSWER✔✔-streak artifacts
for soft tissue neck imaging, the patient is positioned ______________ , and arms relaxed ________________ at
the patients side to prevent artifact from shoulders - VERIFIED ANSWER✔✔-supine, caudally
performing soft tissue neck exams without contrast is __________ - VERIFIED ANSWER✔✔-rare
soft tissue neck exams without contrast are usually only done when the patient cant tolerate contrast media, or if
they are looking at a _____________ injury - VERIFIED ANSWER✔✔-bone injury (c-spine)
axial soft tissue neck scans include from the ___________ orbit to include the entire maxillary sinus, to the lung
__________ (~sternal notch or lower) - VERIFIED ANSWER✔✔-mid (sometimes superior), apex
scout for soft tissue neck: - VERIFIED ANSWER✔✔-lateral (sometimes AP as well)
the lateral soft tissue neck scout image must include from the ______________ to the _________________ heads
- VERIFIED ANSWER✔✔-orbits, clavicular
