CT REGISTRY FINAL EXAM ACTUAL QUESTIONS AND
ANSWERS SURE A+
✔✔The portion of the nephron responsible for filtration of unwanted materials from the
blood plasma is called the - ✔✔Glomerulus
The glomerulus is the portion of the nephron responsible for filtering unwanted
substances from blood plasma. The blood enters into the glomerulus through the
afferent arteriole and exits through the efferent arteriole. The waste fluid leaves the
glomerulus through the proximal tubule
✔✔The ability of an MDCT system to freeze heart motion during a cardiac CT is
described by its - ✔✔The temporal resolution of an MDCT system describes its ability to
freeze the motion of the heart as well as the arterial motion velocity within the coronary
vasculature
✔✔In multislice CT (MSCT), the beam pitch is equal to the table feed per rotation
divided by the - ✔✔Total collimation
The beam pitch, which is unique to multislice CT, is equal to the table feed per rotation
divided by the total collimation. The total collimation is equal to the combined thickness
of all of the sections that are simultaneously acquired with each gantry rotation
✔✔Phantom measurement of the uniformity of a CT system is performed primarily to
assess the negative effects of - ✔✔Beam hardening
✔✔Which of the following components of the CT system is the most common cause of
ring artifacts on the reconstructed CT image? - ✔✔Ring artifacts are typically cause by
faulty detectors. An error in a detecor results in back-projection of an incorrect ring of
density on the reconstructed CT image.
✔✔Cardiac CT images are typically acquired during which phase of the heart's cycle? -
✔✔diastolic (relaxation) phase
The heart optimally imaged with the least artifact from motion during its period of
relaxation, otherwise known as the diastolic phase of the cardiac cycle.
✔✔Each iliac artery bifurcates into the internal and external iliac arteries at about the
level of - ✔✔L5-S1
✔✔The volume of a voxel may be calculated by multiplying the pixel dimension (mm2)
by the _____________? - ✔✔section width
,As a geometric cuboid, the volume of a voxel may be calculated as the product of the
pixel area dimension (mm2) and the section width (mm). The pixel dimension (d) must
be first calculated by dividing the display field of view (DFOV) by the matrix size. The
area of the pixel may then be found by squaring the value of d (mm). The unit of
measurement for voxel of volume is mm3
✔✔Which of the following is the primary interaction between x-ray photons and tissue
during computed tomography? - ✔✔Compton effect
✔✔The technique that provides the detail of the outer portions of the 3D model while
maintaining the typical CT detail of the lungs inside is called - ✔✔Surface rendering
Computer programs are capable of constructing 3D models of anatomy with several
different types of rendering techniques. A surface-rendered 3D model provides excellent
surface anatomy while maintaining the normal cross-sectional anatomy apperance of
the volume inside the model.
✔✔During CT perfusion studies, the quanity of blood (in mL) contained within 100g of
brain tissue is termed the - ✔✔Answer: C. cerebral blood volume (CBV)
✔✔Which of the following is/are included in the signs and symptoms of hypovolemic
shock?
(1) hypertension
(2) oliguria
(3) pallor - ✔✔Answer: C. 2 and 3 only
Hypovolemic shock is caused by an insufficient volume of circulating blood. The
common signs and symptoms of hypocolemic shock are pallor (absence of color in the
skin), hypotension, tachycardia, and oliguria (decrease urine output)
✔✔During a CT examination of the abdomen including intravenous administration of an
iodinated contrast agent, which of the following abnormal findings could appear
hyperdense in comparison with surrounding material? - ✔✔Gallstones
✔✔Which of the following units is used to quantify absorbed dose? - ✔✔grays (Gy)
✔✔Coronal imaging through the paranasal sinuses is typically performed with the plane
of imaging: - ✔✔Perpendicular to the hard palate
,✔✔which of the following manipulations involves the use of image data? - ✔✔window
width and level changes
✔✔Cupping artifacts most commonly occur where? - ✔✔The brain
Cupping artifacts occur when the periphery of the image has a much greater density
than the center
✔✔In patients who are left dominant, the posterior descending artery branches from
the: - ✔✔Left circumflex artery
8% of population is considered left dominant
✔✔A CT system measures the average linear attenuation coefficient of a voxel of tissue
to be 0.189. The linear attenuation coefficient of water for this scanner equals 0.181.
The CT number assigned to the pixel representing this voxel of tissue equals. - ✔✔The
CT number of a pixel may be calculated by subtracting the linear attenuation coefficient
of water from the linear attenuation coefficient of tissue within the voxel. The number is
divided by the linear attenuation coefficient of water. The quotient is multiplied by a
contrast factor of 1000 to yield the value of the pixel in Hounsfield units.
✔✔Which of the following phases of IV contrast agent administration provides the best
gastric and intestinal wall enhancement - ✔✔portal venous
✔✔An Agaston Score of 250 on an MDCT cardiac examination for Coronary Artery
calcification is rated as - ✔✔Moderate
The Agaston system quantifies coronary artery calcium as minimal (1-10), mild (11-
100), moderate (101-400), and extensive (>400)
✔✔During a Coronary Artery CTA, single-segment reconstruction of a 400-msec
rotation scan results in a temperal resolution of - ✔✔200 msec
During single-segment, or half-scan reconstruction, data from only half a gantry rotation
is used, resulting in a temperal resolution equal to one-half the gantry rotation time
✔✔The primary indication for a non-contrast cardiac MDCT examination is - ✔✔Answer:
C. Coronary Artery calcium quantification
The primary indication for non-contrast cardiac MDCT is coronary artery calcium (CAC)
quantification for the assessment of atherosclerotic disease
✔✔The branches of the left coronary artery include the - ✔✔left anterior descending
artery
, left circumflex artery
✔✔The approximate inherent filtration of the CT x-ray amounts to an aluminum
equivalent of - ✔✔The tube housing, cooling oil, and so on, consitite the inherent
filtration, which amounts to approximately 3.0 mm of aluminum equivalent filtration.
✔✔Quantitive computed tomography (QCT) is a specialized technique used most often
for the diagnosis of - ✔✔Answer: B. osteoporosis
Quantitive computed tomography (QCT) is used to measure the mineral content of
bone. Density measurements of the patient's bone are compared with density
measurements of reference phantom. The bone mineral density (BMD) values are
compared with normal values to assess osteoporosis
✔✔What indicates a vagal reaction to iodinated intravenous contrast media? - ✔✔A
combination of brachycardia (heart rate below 50 BPM) and hypotension (systolic
pressure below 80 mm hg)
✔✔What is the Lambert-Beer law used to calculate - ✔✔attenuation coefficient of a
volume of material
✔✔The soft center of each intervertebral disk is the - ✔✔nucleus pulposus
✔✔Which of the following would most likely require intravenous contrast injection for
accurate differentiation during a CT of the abdomen? renal stone, diverticulitis, renal
cyst, angiomyolipoma - ✔✔Renal cyst.. all the others can be diagnosed without iv
contrast
✔✔What are the categories of isolation technique? - ✔✔drainage-secretion precautions,
enteric precautions, acid-fast bacillus isolation, respiratory isolation, contact isolation,
and strict isolation
✔✔What are reference detectors used for? - ✔✔Reference detectors are used to
measure the incident radiation intensity. This information is used by the computer during
the calculation of the linear attenuation coefficient. If the patient is placed incorrectly in
the gantry, the reference detectors may be partially blocked, causing an out of field
artifact
✔✔What are the components of the uterine wall? - ✔✔outter layer- perimetrium
middle layer- myometrium
inner layer- endometrium
ANSWERS SURE A+
✔✔The portion of the nephron responsible for filtration of unwanted materials from the
blood plasma is called the - ✔✔Glomerulus
The glomerulus is the portion of the nephron responsible for filtering unwanted
substances from blood plasma. The blood enters into the glomerulus through the
afferent arteriole and exits through the efferent arteriole. The waste fluid leaves the
glomerulus through the proximal tubule
✔✔The ability of an MDCT system to freeze heart motion during a cardiac CT is
described by its - ✔✔The temporal resolution of an MDCT system describes its ability to
freeze the motion of the heart as well as the arterial motion velocity within the coronary
vasculature
✔✔In multislice CT (MSCT), the beam pitch is equal to the table feed per rotation
divided by the - ✔✔Total collimation
The beam pitch, which is unique to multislice CT, is equal to the table feed per rotation
divided by the total collimation. The total collimation is equal to the combined thickness
of all of the sections that are simultaneously acquired with each gantry rotation
✔✔Phantom measurement of the uniformity of a CT system is performed primarily to
assess the negative effects of - ✔✔Beam hardening
✔✔Which of the following components of the CT system is the most common cause of
ring artifacts on the reconstructed CT image? - ✔✔Ring artifacts are typically cause by
faulty detectors. An error in a detecor results in back-projection of an incorrect ring of
density on the reconstructed CT image.
✔✔Cardiac CT images are typically acquired during which phase of the heart's cycle? -
✔✔diastolic (relaxation) phase
The heart optimally imaged with the least artifact from motion during its period of
relaxation, otherwise known as the diastolic phase of the cardiac cycle.
✔✔Each iliac artery bifurcates into the internal and external iliac arteries at about the
level of - ✔✔L5-S1
✔✔The volume of a voxel may be calculated by multiplying the pixel dimension (mm2)
by the _____________? - ✔✔section width
,As a geometric cuboid, the volume of a voxel may be calculated as the product of the
pixel area dimension (mm2) and the section width (mm). The pixel dimension (d) must
be first calculated by dividing the display field of view (DFOV) by the matrix size. The
area of the pixel may then be found by squaring the value of d (mm). The unit of
measurement for voxel of volume is mm3
✔✔Which of the following is the primary interaction between x-ray photons and tissue
during computed tomography? - ✔✔Compton effect
✔✔The technique that provides the detail of the outer portions of the 3D model while
maintaining the typical CT detail of the lungs inside is called - ✔✔Surface rendering
Computer programs are capable of constructing 3D models of anatomy with several
different types of rendering techniques. A surface-rendered 3D model provides excellent
surface anatomy while maintaining the normal cross-sectional anatomy apperance of
the volume inside the model.
✔✔During CT perfusion studies, the quanity of blood (in mL) contained within 100g of
brain tissue is termed the - ✔✔Answer: C. cerebral blood volume (CBV)
✔✔Which of the following is/are included in the signs and symptoms of hypovolemic
shock?
(1) hypertension
(2) oliguria
(3) pallor - ✔✔Answer: C. 2 and 3 only
Hypovolemic shock is caused by an insufficient volume of circulating blood. The
common signs and symptoms of hypocolemic shock are pallor (absence of color in the
skin), hypotension, tachycardia, and oliguria (decrease urine output)
✔✔During a CT examination of the abdomen including intravenous administration of an
iodinated contrast agent, which of the following abnormal findings could appear
hyperdense in comparison with surrounding material? - ✔✔Gallstones
✔✔Which of the following units is used to quantify absorbed dose? - ✔✔grays (Gy)
✔✔Coronal imaging through the paranasal sinuses is typically performed with the plane
of imaging: - ✔✔Perpendicular to the hard palate
,✔✔which of the following manipulations involves the use of image data? - ✔✔window
width and level changes
✔✔Cupping artifacts most commonly occur where? - ✔✔The brain
Cupping artifacts occur when the periphery of the image has a much greater density
than the center
✔✔In patients who are left dominant, the posterior descending artery branches from
the: - ✔✔Left circumflex artery
8% of population is considered left dominant
✔✔A CT system measures the average linear attenuation coefficient of a voxel of tissue
to be 0.189. The linear attenuation coefficient of water for this scanner equals 0.181.
The CT number assigned to the pixel representing this voxel of tissue equals. - ✔✔The
CT number of a pixel may be calculated by subtracting the linear attenuation coefficient
of water from the linear attenuation coefficient of tissue within the voxel. The number is
divided by the linear attenuation coefficient of water. The quotient is multiplied by a
contrast factor of 1000 to yield the value of the pixel in Hounsfield units.
✔✔Which of the following phases of IV contrast agent administration provides the best
gastric and intestinal wall enhancement - ✔✔portal venous
✔✔An Agaston Score of 250 on an MDCT cardiac examination for Coronary Artery
calcification is rated as - ✔✔Moderate
The Agaston system quantifies coronary artery calcium as minimal (1-10), mild (11-
100), moderate (101-400), and extensive (>400)
✔✔During a Coronary Artery CTA, single-segment reconstruction of a 400-msec
rotation scan results in a temperal resolution of - ✔✔200 msec
During single-segment, or half-scan reconstruction, data from only half a gantry rotation
is used, resulting in a temperal resolution equal to one-half the gantry rotation time
✔✔The primary indication for a non-contrast cardiac MDCT examination is - ✔✔Answer:
C. Coronary Artery calcium quantification
The primary indication for non-contrast cardiac MDCT is coronary artery calcium (CAC)
quantification for the assessment of atherosclerotic disease
✔✔The branches of the left coronary artery include the - ✔✔left anterior descending
artery
, left circumflex artery
✔✔The approximate inherent filtration of the CT x-ray amounts to an aluminum
equivalent of - ✔✔The tube housing, cooling oil, and so on, consitite the inherent
filtration, which amounts to approximately 3.0 mm of aluminum equivalent filtration.
✔✔Quantitive computed tomography (QCT) is a specialized technique used most often
for the diagnosis of - ✔✔Answer: B. osteoporosis
Quantitive computed tomography (QCT) is used to measure the mineral content of
bone. Density measurements of the patient's bone are compared with density
measurements of reference phantom. The bone mineral density (BMD) values are
compared with normal values to assess osteoporosis
✔✔What indicates a vagal reaction to iodinated intravenous contrast media? - ✔✔A
combination of brachycardia (heart rate below 50 BPM) and hypotension (systolic
pressure below 80 mm hg)
✔✔What is the Lambert-Beer law used to calculate - ✔✔attenuation coefficient of a
volume of material
✔✔The soft center of each intervertebral disk is the - ✔✔nucleus pulposus
✔✔Which of the following would most likely require intravenous contrast injection for
accurate differentiation during a CT of the abdomen? renal stone, diverticulitis, renal
cyst, angiomyolipoma - ✔✔Renal cyst.. all the others can be diagnosed without iv
contrast
✔✔What are the categories of isolation technique? - ✔✔drainage-secretion precautions,
enteric precautions, acid-fast bacillus isolation, respiratory isolation, contact isolation,
and strict isolation
✔✔What are reference detectors used for? - ✔✔Reference detectors are used to
measure the incident radiation intensity. This information is used by the computer during
the calculation of the linear attenuation coefficient. If the patient is placed incorrectly in
the gantry, the reference detectors may be partially blocked, causing an out of field
artifact
✔✔What are the components of the uterine wall? - ✔✔outter layer- perimetrium
middle layer- myometrium
inner layer- endometrium
