CT BOARD REVIEW QUESTIONS WITH
100% COMPLETE SOLUTIONS
which is not a synonym for the preliminary image taken at the start of a CT exam?
a. topogram
b. scout
c. scanogram
d. spiral - VERIFIED ANSWER✔✔-d. spiral
the ability of a system to differentiate on the image, objects with similar densities is known as....
a. high contrast resolution
b. low contrast resolution
c. spatial resolution
d. temporal resolution - VERIFIED ANSWER✔✔-b. low contrast resolution
each 2 dimensional square of data that make up the CT image is called a ...
a. pixel
b. voxel
c. matrix
d. fragment - VERIFIED ANSWER✔✔-a. pixel
How many pixels are contained in a 1,024 matrix image?
a. 1,024
b. 2,048
c. 262,144
d. 1,048,576 - VERIFIED ANSWER✔✔-d. 1,048,576
Beam attenuation can be defined as:
A. The phenomenon by which artifacts result when lower energy photons are preferentially absorbed, leaving
only higher-intensity photons to strike the detector array.
B. Xray energy that is produced from bombarding a substance with fast moving electrons.
C. The ability of the detector to capture transmitted photons and change them to electronic signals.
D. The phenomenon by which an xray beam passing through a structure is decreased in intensity or amount
because of absorption and interaction with matter. - VERIFIED ANSWER✔✔-d. the phenomenon by which an x
ray beam passing through a structure is decreased in intensity or amount because of absorption and interaction
with matter
which of the following is a low attenuation structure?
a. iodine filled aorta
b. rib
c. trachea
d. calcified arteries - VERIFIED ANSWER✔✔-c. trachea
An object is slightly less dense than water. What is the expected Hounsfield measurement?
a. -940
b. -10
c. 50
d. 850 - VERIFIED ANSWER✔✔-b. -10
Why does the administration of iodinated contrast media result in an enhanced image?
A. Iodinated contrast material increases the ability of the enhanced structure to attenuate the xray beam.
B. Iodinated contrast material decreases the average photon energy of the xray beam; therefore more photons are
absorbed by the patient.
C. The administration of contrast material results in a smaller pixel, thereby increasing spatial resolution, which
, results in an enhanced image. - VERIFIED ANSWER✔✔-a. iodinated contrast material increases the ability of
the enhanced structure to attenuate the xray beam
the xray beam sources for CT produce xray energy that is polychromatic. this means that:
a. when viewed by the naked eye, the beam exhibits many different colors
b. it produces as a byproduct a substance known as polychlorinated biphenyl
c. photons contained in the beam are all of the same wavelength
d. the beam comprises photons with varying energies - VERIFIED ANSWER✔✔-d. the beam comprises photons
with varying energies
an object that appears on the image but is not present in the object scanned is called an
a. artifact
b. anomaly
c. shadow
d. ghost - VERIFIED ANSWER✔✔-a. artifact
which is an advantage of filtering the xray beam?
a. filtering reduces the anode heat load
b. a filtered beam produces images with substantially less quantum mottle
c. filtering the beam prevents energy from being converted to heat, therefore 100% of the energy is converted to
xrays
d. filtering reduces radiation dose to the patient - VERIFIED ANSWER✔✔-d. filtering reduces radiation dose to
the patient
which is another name for raw data
a. image data
b. scan data
c. reconstructed data
d. displayed data - VERIFIED ANSWER✔✔-b. scan data
which of the following components is NOT housed within the gantry?
a. three phase generator
b. high frequency generator
c. slip rings
d. xenon gas detectors - VERIFIED ANSWER✔✔-a. three phase generator
the power capacity of the generator is listed in
a. miliampers (mA)
b. thousand heat units (KHU)
c. million heat units (MHU)
d. kilowatts (kW) - VERIFIED ANSWER✔✔-d. kilowatts (kW)
which of the following describes a slip ring device?
a. recoiling system cable used to rotate the gantry frame
b. brushlike apparatus that provides continuous electrical power and electronic communication across a rotating
surface
c. device used to shape the xray beam, thereby reducing the radiation dose to the patient and reducing image
artifact
d. device that restricts the xray beam emerging from the gantry to thin ribbons - VERIFIED ANSWER✔✔-b.
brushlike apparatus that provides continuous electrical power and electronic communication across a rotating
surface
which is a DISADVANTAGE of a small focal spot size?
a. reduced spatial resolution
b. reduced detector efficiency
c. increased penumbra
d. reduced heat capacity - VERIFIED ANSWER✔✔-d. reduced heat capactiy
100% COMPLETE SOLUTIONS
which is not a synonym for the preliminary image taken at the start of a CT exam?
a. topogram
b. scout
c. scanogram
d. spiral - VERIFIED ANSWER✔✔-d. spiral
the ability of a system to differentiate on the image, objects with similar densities is known as....
a. high contrast resolution
b. low contrast resolution
c. spatial resolution
d. temporal resolution - VERIFIED ANSWER✔✔-b. low contrast resolution
each 2 dimensional square of data that make up the CT image is called a ...
a. pixel
b. voxel
c. matrix
d. fragment - VERIFIED ANSWER✔✔-a. pixel
How many pixels are contained in a 1,024 matrix image?
a. 1,024
b. 2,048
c. 262,144
d. 1,048,576 - VERIFIED ANSWER✔✔-d. 1,048,576
Beam attenuation can be defined as:
A. The phenomenon by which artifacts result when lower energy photons are preferentially absorbed, leaving
only higher-intensity photons to strike the detector array.
B. Xray energy that is produced from bombarding a substance with fast moving electrons.
C. The ability of the detector to capture transmitted photons and change them to electronic signals.
D. The phenomenon by which an xray beam passing through a structure is decreased in intensity or amount
because of absorption and interaction with matter. - VERIFIED ANSWER✔✔-d. the phenomenon by which an x
ray beam passing through a structure is decreased in intensity or amount because of absorption and interaction
with matter
which of the following is a low attenuation structure?
a. iodine filled aorta
b. rib
c. trachea
d. calcified arteries - VERIFIED ANSWER✔✔-c. trachea
An object is slightly less dense than water. What is the expected Hounsfield measurement?
a. -940
b. -10
c. 50
d. 850 - VERIFIED ANSWER✔✔-b. -10
Why does the administration of iodinated contrast media result in an enhanced image?
A. Iodinated contrast material increases the ability of the enhanced structure to attenuate the xray beam.
B. Iodinated contrast material decreases the average photon energy of the xray beam; therefore more photons are
absorbed by the patient.
C. The administration of contrast material results in a smaller pixel, thereby increasing spatial resolution, which
, results in an enhanced image. - VERIFIED ANSWER✔✔-a. iodinated contrast material increases the ability of
the enhanced structure to attenuate the xray beam
the xray beam sources for CT produce xray energy that is polychromatic. this means that:
a. when viewed by the naked eye, the beam exhibits many different colors
b. it produces as a byproduct a substance known as polychlorinated biphenyl
c. photons contained in the beam are all of the same wavelength
d. the beam comprises photons with varying energies - VERIFIED ANSWER✔✔-d. the beam comprises photons
with varying energies
an object that appears on the image but is not present in the object scanned is called an
a. artifact
b. anomaly
c. shadow
d. ghost - VERIFIED ANSWER✔✔-a. artifact
which is an advantage of filtering the xray beam?
a. filtering reduces the anode heat load
b. a filtered beam produces images with substantially less quantum mottle
c. filtering the beam prevents energy from being converted to heat, therefore 100% of the energy is converted to
xrays
d. filtering reduces radiation dose to the patient - VERIFIED ANSWER✔✔-d. filtering reduces radiation dose to
the patient
which is another name for raw data
a. image data
b. scan data
c. reconstructed data
d. displayed data - VERIFIED ANSWER✔✔-b. scan data
which of the following components is NOT housed within the gantry?
a. three phase generator
b. high frequency generator
c. slip rings
d. xenon gas detectors - VERIFIED ANSWER✔✔-a. three phase generator
the power capacity of the generator is listed in
a. miliampers (mA)
b. thousand heat units (KHU)
c. million heat units (MHU)
d. kilowatts (kW) - VERIFIED ANSWER✔✔-d. kilowatts (kW)
which of the following describes a slip ring device?
a. recoiling system cable used to rotate the gantry frame
b. brushlike apparatus that provides continuous electrical power and electronic communication across a rotating
surface
c. device used to shape the xray beam, thereby reducing the radiation dose to the patient and reducing image
artifact
d. device that restricts the xray beam emerging from the gantry to thin ribbons - VERIFIED ANSWER✔✔-b.
brushlike apparatus that provides continuous electrical power and electronic communication across a rotating
surface
which is a DISADVANTAGE of a small focal spot size?
a. reduced spatial resolution
b. reduced detector efficiency
c. increased penumbra
d. reduced heat capacity - VERIFIED ANSWER✔✔-d. reduced heat capactiy
