CT REGISTRY EVALUATION ACTUAL ALL QUESTIONS AND
ANSWERS SURE A+
✔✔When the scan plane is perpendicular to the subtalar joint and the gantry is tilted
towards the patient at around 25 degrees, what is the directly acquired imaging plane? -
✔✔Oblique coronal plane
✔✔What would the likely diagnosis be on a homogeneous adrenal mass with an
attenuation number on an unenhanced CT of less than 10HU? - ✔✔Adenoma
✔✔Normal GFR levels? - ✔✔Men: 70 +/- 14 mL/min/m
Women: 60 +/- 10 mL/min/m
✔✔Normal BUN levels? - ✔✔8-25mg/100ml
✔✔Blooming - ✔✔Potential overestimation of vessel calcification due to partial volume
artifact. Can be mitigated by increasing spatial resolution
✔✔Out pocketing of the wall of the colon - ✔✔Diverticulosis
✔✔How many detectors does the 2nd Generation Scanner have? - ✔✔Detector Array
(5-30) (fan beam)
✔✔What is the range for Hounsfield units? - ✔✔-1000 air to + 3000 dense bone
Zero represents water
✔✔How do you calculate pitch? - ✔✔Couch movement each 360 degree rotation/ beam
width
✔✔example (pitch) : During a 360 degree x-ray tube rotation, the patient moves 8 mm,
beam width is 5 mm.. whats the pitch? - ✔✔Couch movement / beam width
8mm/5mm = 1.6:1
✔✔What is the slip ring technology? - ✔✔makes spiral or helical movement possible of
a single 360 degree...then a pause while the gantry was wound back to start followed by
another 360 degree
✔✔The slip ring allows - ✔✔the power and electrical signals to be transmitted through
stationary rings within the gantry, thus eliminating cables which make continuous
rotation impossible
✔✔Translate-rotate was used in what generation CT scanners - ✔✔1st and 2nd
generation
,✔✔Each translation of a source detector assembly produces what? - ✔✔a projection
✔✔why is contrast resolution superior in CT rather than conventional radiography? -
✔✔Beam collimation
✔✔What would be the pitch if the couch movement was 24mm and the beam width was
12mm? - ✔✔24/12=2= 2:1
✔✔What would be the pitch if the couch movement was 20 mm and the beam width
was 8mm? - ✔✔20/8=2.5= 2.5:1
✔✔Describe the difference between pre-patient and pre-detector collimation? - ✔✔Pre-
patient: determines dose; pre-detector: slice thickness/ sensitivity
✔✔Slice thickness can also be expressed as - ✔✔sensitivity profile
✔✔When the source-detector assembly makes one sweep across the patient, this is
known as a __________. - ✔✔translation
✔✔The fan beam (in second, third, and fourth) caused an increase in radiation intensity
toward the edges of the beam. What was done to compensate for this? -
✔✔implementation of a bow tie filter
✔✔_____ generation CT imaging systems were the first designed so that the source
and detector arrays rotated around the patient. No translation was required. - ✔✔Third
✔✔_____ generation CT scanners used a curvilinear detector array and a fan beam.
This results in a constant source-to-detector path length, which is an advantage for
good image reconstruction - ✔✔Third
✔✔This artifact was typically caused by malfunction of any one detector or bank of
detectors in a CT imaging system. This lack of signal caused a ring to appear on
reconstruction known as a - ✔✔Ring artifact (prominent in 3rd gen.)
✔✔The ______ generation of CT scanners use a rotate-stationary configuration. The x-
ray source rotates around the patient, but the detectors remain stationary. This is
accomplished through a fixed array of detectors containing as many as 4000 elements -
✔✔Fourth Generation
✔✔What are the components within the gantry? - ✔✔- x-ray tube
- detector array
- high voltage generator
-slip rings
,-DAS (data-acquisition system)
- pt support couch
- mechanical support for each of these components
✔✔Modulation transfer function - ✔✔Most commonly used method of describing spatial
resolution ability. It is often used to graphically represent a systems capability of passing
information to the observer.
✔✔The ability to reconstruct an image at any z-axis position is possible because of a
mathematical process called - ✔✔interpolation
✔✔Spiral (helical) CT (made possible by slip rings; continuous) - ✔✔With _____ CT, the
x-ray tube is continuously energized, and data are collected continuously. An image can
be constructed along any desired z-axis position along the pt
✔✔Depolarization - ✔✔Once an electrical cell generates an electrical impulse, this
electrical impulse causes the ions to cross the cell membrane and causes the action
potential. (this is when the muscle cell can squeeze down)
✔✔Repolarization - ✔✔the return of the ions to their pervious resting state, which
corresponds with relaxation of the myocardial muscle
✔✔Cardiac cells at rest are considered ______________, meaning no electrical activity
takes place. - ✔✔polarized
✔✔Veins-- blood moving.. - ✔✔to the heart
✔✔Arteries--- blood moving.. - ✔✔away from the heart
✔✔What are the two Atrioventricular valves? (AV valves) - ✔✔Tricuspid valve---
separates the right atrium and right ventricle
Mitral or bicuspid valve---- separates the left atrium and left ventricle
✔✔What are the two semilunar valves? - ✔✔Pulmonary valve---- separates the Right
ventricle and pulmonary arteries
Aortic valve---- separates the left ventricle and aorta
✔✔Describe LUB (1st heart sound/S1) - ✔✔Blood has entered the right and left
Ventricles and the Tricuspid and Mitral valve snap shut (as to not let any blood go
backwards) creating our first heart sound.. LUB
Also.. at this moment pulmonary and aortic valves just opened up
, ✔✔Describe DUB (2nd heart sound/ S2) - ✔✔Blood has made its way through the
pulmonary and aortic valves and they will now snap shut. Creating out second heart
sound.. DUB
also.. at this moment tricuspid and mitral valves have just opened up
✔✔As the electrical impulse leaves the SA node (in right atrium) it is conducted through
the left atrium by way of the _________________, through the right atria, via the atrial
tracts - ✔✔Bachmanns bundle
✔✔What is the purpose of the AV node? - ✔✔responsible for delaying the impulses the
reach it. Why do we need a delay? if the atria and ventricles were to contract at the
same time .. it wouldn't allow blood to move through and out of the heart and the heart
would be working against itself. this delay is about .1 seconds. It waits for the
completion of atrial emptying and ventricular filling, to allow the cardiac muscle to
stretch to it's fullest for peak cardiac output.
✔✔Just south of the AV node.. it is continued by something called the ___________ -
✔✔Bundle of His
✔✔Describe the Bundle of His - ✔✔resumes rapid conduction of the impulses through
the ventricles. It makes up the distal part of the AV junction and extends into the
ventricles next to the interventriular septum. It then divides into the right and left bundle
branches.
✔✔After the bundle of His the electrical signal will dash out from the bundle branches in
different directions into the endocardium and deep into the myocardial tissue .... this
occurs through the _________________ - ✔✔Purkinje Fibers
✔✔Any cardiac impulse originating outside the SA node is considered abnormal and is
referred to as an ____________ - ✔✔ectopic beat
✔✔Examples of a moderate or intermediate reaction to iodinated contrast -
✔✔dyspnea, severe vomiting, faintness, chest pain, and seizures
✔✔The term appendicolith is applied to which pathological condition concerning the
appendix - ✔✔calcification
✔✔What does CT perfusion evaluates? - ✔✔The initial passing of iodinated contrast
through the brain vasculature
✔✔Orbit CT images are acquired parallel to? - ✔✔IOML
ANSWERS SURE A+
✔✔When the scan plane is perpendicular to the subtalar joint and the gantry is tilted
towards the patient at around 25 degrees, what is the directly acquired imaging plane? -
✔✔Oblique coronal plane
✔✔What would the likely diagnosis be on a homogeneous adrenal mass with an
attenuation number on an unenhanced CT of less than 10HU? - ✔✔Adenoma
✔✔Normal GFR levels? - ✔✔Men: 70 +/- 14 mL/min/m
Women: 60 +/- 10 mL/min/m
✔✔Normal BUN levels? - ✔✔8-25mg/100ml
✔✔Blooming - ✔✔Potential overestimation of vessel calcification due to partial volume
artifact. Can be mitigated by increasing spatial resolution
✔✔Out pocketing of the wall of the colon - ✔✔Diverticulosis
✔✔How many detectors does the 2nd Generation Scanner have? - ✔✔Detector Array
(5-30) (fan beam)
✔✔What is the range for Hounsfield units? - ✔✔-1000 air to + 3000 dense bone
Zero represents water
✔✔How do you calculate pitch? - ✔✔Couch movement each 360 degree rotation/ beam
width
✔✔example (pitch) : During a 360 degree x-ray tube rotation, the patient moves 8 mm,
beam width is 5 mm.. whats the pitch? - ✔✔Couch movement / beam width
8mm/5mm = 1.6:1
✔✔What is the slip ring technology? - ✔✔makes spiral or helical movement possible of
a single 360 degree...then a pause while the gantry was wound back to start followed by
another 360 degree
✔✔The slip ring allows - ✔✔the power and electrical signals to be transmitted through
stationary rings within the gantry, thus eliminating cables which make continuous
rotation impossible
✔✔Translate-rotate was used in what generation CT scanners - ✔✔1st and 2nd
generation
,✔✔Each translation of a source detector assembly produces what? - ✔✔a projection
✔✔why is contrast resolution superior in CT rather than conventional radiography? -
✔✔Beam collimation
✔✔What would be the pitch if the couch movement was 24mm and the beam width was
12mm? - ✔✔24/12=2= 2:1
✔✔What would be the pitch if the couch movement was 20 mm and the beam width
was 8mm? - ✔✔20/8=2.5= 2.5:1
✔✔Describe the difference between pre-patient and pre-detector collimation? - ✔✔Pre-
patient: determines dose; pre-detector: slice thickness/ sensitivity
✔✔Slice thickness can also be expressed as - ✔✔sensitivity profile
✔✔When the source-detector assembly makes one sweep across the patient, this is
known as a __________. - ✔✔translation
✔✔The fan beam (in second, third, and fourth) caused an increase in radiation intensity
toward the edges of the beam. What was done to compensate for this? -
✔✔implementation of a bow tie filter
✔✔_____ generation CT imaging systems were the first designed so that the source
and detector arrays rotated around the patient. No translation was required. - ✔✔Third
✔✔_____ generation CT scanners used a curvilinear detector array and a fan beam.
This results in a constant source-to-detector path length, which is an advantage for
good image reconstruction - ✔✔Third
✔✔This artifact was typically caused by malfunction of any one detector or bank of
detectors in a CT imaging system. This lack of signal caused a ring to appear on
reconstruction known as a - ✔✔Ring artifact (prominent in 3rd gen.)
✔✔The ______ generation of CT scanners use a rotate-stationary configuration. The x-
ray source rotates around the patient, but the detectors remain stationary. This is
accomplished through a fixed array of detectors containing as many as 4000 elements -
✔✔Fourth Generation
✔✔What are the components within the gantry? - ✔✔- x-ray tube
- detector array
- high voltage generator
-slip rings
,-DAS (data-acquisition system)
- pt support couch
- mechanical support for each of these components
✔✔Modulation transfer function - ✔✔Most commonly used method of describing spatial
resolution ability. It is often used to graphically represent a systems capability of passing
information to the observer.
✔✔The ability to reconstruct an image at any z-axis position is possible because of a
mathematical process called - ✔✔interpolation
✔✔Spiral (helical) CT (made possible by slip rings; continuous) - ✔✔With _____ CT, the
x-ray tube is continuously energized, and data are collected continuously. An image can
be constructed along any desired z-axis position along the pt
✔✔Depolarization - ✔✔Once an electrical cell generates an electrical impulse, this
electrical impulse causes the ions to cross the cell membrane and causes the action
potential. (this is when the muscle cell can squeeze down)
✔✔Repolarization - ✔✔the return of the ions to their pervious resting state, which
corresponds with relaxation of the myocardial muscle
✔✔Cardiac cells at rest are considered ______________, meaning no electrical activity
takes place. - ✔✔polarized
✔✔Veins-- blood moving.. - ✔✔to the heart
✔✔Arteries--- blood moving.. - ✔✔away from the heart
✔✔What are the two Atrioventricular valves? (AV valves) - ✔✔Tricuspid valve---
separates the right atrium and right ventricle
Mitral or bicuspid valve---- separates the left atrium and left ventricle
✔✔What are the two semilunar valves? - ✔✔Pulmonary valve---- separates the Right
ventricle and pulmonary arteries
Aortic valve---- separates the left ventricle and aorta
✔✔Describe LUB (1st heart sound/S1) - ✔✔Blood has entered the right and left
Ventricles and the Tricuspid and Mitral valve snap shut (as to not let any blood go
backwards) creating our first heart sound.. LUB
Also.. at this moment pulmonary and aortic valves just opened up
, ✔✔Describe DUB (2nd heart sound/ S2) - ✔✔Blood has made its way through the
pulmonary and aortic valves and they will now snap shut. Creating out second heart
sound.. DUB
also.. at this moment tricuspid and mitral valves have just opened up
✔✔As the electrical impulse leaves the SA node (in right atrium) it is conducted through
the left atrium by way of the _________________, through the right atria, via the atrial
tracts - ✔✔Bachmanns bundle
✔✔What is the purpose of the AV node? - ✔✔responsible for delaying the impulses the
reach it. Why do we need a delay? if the atria and ventricles were to contract at the
same time .. it wouldn't allow blood to move through and out of the heart and the heart
would be working against itself. this delay is about .1 seconds. It waits for the
completion of atrial emptying and ventricular filling, to allow the cardiac muscle to
stretch to it's fullest for peak cardiac output.
✔✔Just south of the AV node.. it is continued by something called the ___________ -
✔✔Bundle of His
✔✔Describe the Bundle of His - ✔✔resumes rapid conduction of the impulses through
the ventricles. It makes up the distal part of the AV junction and extends into the
ventricles next to the interventriular septum. It then divides into the right and left bundle
branches.
✔✔After the bundle of His the electrical signal will dash out from the bundle branches in
different directions into the endocardium and deep into the myocardial tissue .... this
occurs through the _________________ - ✔✔Purkinje Fibers
✔✔Any cardiac impulse originating outside the SA node is considered abnormal and is
referred to as an ____________ - ✔✔ectopic beat
✔✔Examples of a moderate or intermediate reaction to iodinated contrast -
✔✔dyspnea, severe vomiting, faintness, chest pain, and seizures
✔✔The term appendicolith is applied to which pathological condition concerning the
appendix - ✔✔calcification
✔✔What does CT perfusion evaluates? - ✔✔The initial passing of iodinated contrast
through the brain vasculature
✔✔Orbit CT images are acquired parallel to? - ✔✔IOML
