CT REGISTRY REVIEW EXAM QUESTIONS
WITH COMPLETE SOLUTIONS
Tungsten is used as the target material on the tube's anode b/c it has a __ atomic number and a __ melting point.
a. low, high
b. high, low
c. low, low
d. high, high - VERIFIED ANSWER✔✔-d
_____ scanner design was the first to acquire four slices in a single rotation.
a. second generation
b. third generation
c. multi-row detector
d. continuous rotation - VERIFIED ANSWER✔✔-c
The enormous heat that builds up in the CT tube is caused by the:
a. intensity of the x-ray emitted from the tube
b. electron beam between the cathode and the anode in the tube
c. x-ray filter in the tube which absorbs the lower energy photons before they can enter the patient.
d. collision of the electron beam with the tungsten target on the tube anode. - VERIFIED ANSWER✔✔-d
The number of electron that flow from the cathode to the anode in the tube is controlled by the .
a. anode target
b. collimator
c. mA
d. kV - VERIFIED ANSWER✔✔-c
The slip ring on continuous rotation CT scanners:
1. prevents the high voltage cable from winding up
2. allows the exam to commence more rapidly
3. eliminates the need for the reversal of the gantry frame rotation.
a. 1 only
b. 2 only
c. 3 only
d. 1, 2 & 3 - VERIFIED ANSWER✔✔-d
Which of the following is NOT a part of the CT tube?
a. tungsten target
b. collimator
c. rotating anode
d. filament - VERIFIED ANSWER✔✔-b
Which of the following are NOT commonly used on today's commercially available CT scanners?
1. xenon detectors
2. fourth generation scanners
3. continuous rotation
a. 1 only
b. 1 & 2
c. 1, 2 & 3 - VERIFIED ANSWER✔✔-b
Which system components converts the projection attenuation data into the proper digital form for the array
processor?
a. detector
b. photodiode
c. analog to digital converter
d. host computer - VERIFIED ANSWER✔✔-c
,x-ray photons are produced by a fast moving electron:
1. colliding with an atomic nucleus
2. passing close to an atomic nucleus
3. colliding with an electron within an atom and ejecting it
a. 1 only
b. 2 only
c. 3 only
d. 1, 2 & 3 - VERIFIED ANSWER✔✔-d
Which of the following is TRUE regarding solid state detectors?
1. x-ray photons cause the detectors to generate a flash of light
2. they are the detector type used on most CT scanners today
3. they can be used in both third and fourth generation CT systems.
a. 1 only
b. 2 only
c. 3 only
d. 1, 2 & 3 - VERIFIED ANSWER✔✔-d
CT is commonly referred to as al of the following names EXCEPT:
a. computerized axial tomography
b. digital subtraction angiography
c. CAT scan
d. computed tomography - VERIFIED ANSWER✔✔-b
What control does the operator have over the x-ray in the CT exam?
a. the temperature and color of the x-ray can be tuned
b. the energy level and the quantity of x-rays can be selected
c. the volume and tone of the x-ray can be adjusted
d. the phase and frequency of the x-ray can be adjusted - VERIFIED ANSWER✔✔-b
Which of the following statements if TRUE?
1. kV is the voltage potential between the tube cathode and anode while mA ultimately controls the filament
current and, thus, the temperature of the cathode filament.
2. kV controls the energy level of the x-ray photons and mA controls the number of x-ray photons emitted from
the tube.
3. although the kV and the mA affect the operation of the CT x-ray tube, the two parameters have no bearing on
the image quality
a. 1 only
b. 2 only
c. 1 & 2
d. 2 & 3 - VERIFIED ANSWER✔✔-c
Which of the following does NOT affect the quantity of
x-rays that completely penetrates the patient?
1. the distance that the x-ray photons must travel on their course through the patient's body
2. the molecular composition of the tissues through which the x-ray photons pass
3. the type of detector material used
a. 1 only
b. 2 only
c. 3 only
d. 1, 2 & 3 - VERIFIED ANSWER✔✔-c
___made helical imaging possible.
a. Multi-row detector scanners
b. The introduction of second generation scanners
c. The introduction of fourth generation scanners
d. Continuous rotation scanners - VERIFIED ANSWER✔✔-d
Which of the following statements is FALSE regarding the collection of CT data?
,a. long scan times are more desirable b/c they average out motion artifacts
b. the reconstruction process used to create the image occurs in the array processor
c. to collect the complete set of CT data, x-ray must passed through the body at many different angles
d. the detectors measure x-rays which completely penetrate the patient. - VERIFIED ANSWER✔✔-a
Which of the following is a component NOT normally located in the gantry of modern CT system?
a. pre patient collimators
b. solid state detectors
c. array processor
d. x-ray tube - VERIFIED ANSWER✔✔-c
X-rays are used in CT b/c:
a. they are easily produced by the high frequency generator
b. they are less harmful than the heating effects of microwave radiation
c. they penetrate the body according to specific attenuation characteristics of each tissue
d. the FDA imposes no limit on the dose to the patient - VERIFIED ANSWER✔✔-c
X-rays are produced whenever fast moving electrons collide with any form of matter b/c :
1. the electron splits into two x-ray photons of equal energy upon impact with the matter
2. the electron loses kinetic energy which is converted into the emission of an x-ray photon
3. the electron converts the electron it collides with into an x-ray photon
a. 1 only
b. 2 only
c. 3 only
d. 1, 2 & 3 - VERIFIED ANSWER✔✔-b
Bremsstrahlung radiation does NOT include which type of electron activity?
1. collision between an incoming electron and the nucleus of the target atom
2. collision between an incoming electron and an electron in an inner shell of the target atom
3. slowing down of an incoming electron due to the effect of passing close to the positive charge of the nucleus of
the target atom
a. 1 only
b. 2 only
c. 3 only
d. 1, 2 & 3 - VERIFIED ANSWER✔✔-b
The mA determines the :
a. quantity of x-ray photons
b. coefficient of attenuation
c. slice thickness
d. energy level of the x-ray photons - VERIFIED ANSWER✔✔-a
Increased ___ will increase the likelihood that a given x-ray will penetrate a material.
1. kV
2. mA
3. exposure time
a. 1 only
b. 2 only
c. 3 only
d. 1, 2 & 3 - VERIFIED ANSWER✔✔-a
Collimation:
a. is accomplished by electrically blocking x-ray
b. affects the scan time
c. limits the low energy x-ray photons and passes the high energy photons
d. is accomplished by physically blocking x-rays - VERIFIED ANSWER✔✔-d
Scatter radiation is caused by:
a. miscalibrated detector
b. x-rays generated spontaneously in the ambient atmosphere
, c. deflections from the original trajectory of an x-ray photon through the patient
d. improper patient positioning. - VERIFIED ANSWER✔✔-c
Which technology do multi-row detector scanners employ?
a. second generation
b. third generation
c. fourth generation
d. first generation - VERIFIED ANSWER✔✔-b
Which of the following is NOT a function of a PACS system?
a. reconstruction of the image from the raw data
b. long term data storage
c. digital distribution of images
d. image display for the radiologists - VERIFIED ANSWER✔✔-a
Which of the following is TRUE regarding multi-row detector CT scanners?
1. the size of the detectors array along the z direction may be different
2. the attenuation information from adjacent detector arrays may be added together to generate thicker slices
3. all of the detector array may or may not be used
a. 1 only
b. 2 only
c. 3 only
d. 1, 2 & 3 - VERIFIED ANSWER✔✔-d
Which of the following is FALSE regarding CT systems?
1. they are limited to non oblique transverse scanning
2. they cannot generate a straight coronal or sagittal image
3. they have no moving parts.
a. 1 only
b. 2 only
c. 3 only
d. 1, 2 & 3 - VERIFIED ANSWER✔✔-d
Most of the commands from the technologist are received by the :
a. array processor
b. operator's console
c. host computer
d. amplifier - VERIFIED ANSWER✔✔-b
The operator's console may include:
1. monitor
2. keyboard
3.graphic input device
a. 1 only
b. 2 only
c. 3 only
d. 1, 2 & 3 - VERIFIED ANSWER✔✔-d
Which of the following CT scanners design does NOT use an x-ray tube?
a. first generation
b. PET/CT
c. electron beam CT
d. MDCT - VERIFIED ANSWER✔✔-c
Tube interscan delay time refers to:
a. the time between the end of one scan and the start of the next scan during which the tube will cool
b. a quality assurance test performed daily by the technologist
c. the time required for the tube to make a complete 360 revolution about the gantry
d. the length of time required for the production of photons to begin after applying the voltage to the tube -
VERIFIED ANSWER✔✔-a
WITH COMPLETE SOLUTIONS
Tungsten is used as the target material on the tube's anode b/c it has a __ atomic number and a __ melting point.
a. low, high
b. high, low
c. low, low
d. high, high - VERIFIED ANSWER✔✔-d
_____ scanner design was the first to acquire four slices in a single rotation.
a. second generation
b. third generation
c. multi-row detector
d. continuous rotation - VERIFIED ANSWER✔✔-c
The enormous heat that builds up in the CT tube is caused by the:
a. intensity of the x-ray emitted from the tube
b. electron beam between the cathode and the anode in the tube
c. x-ray filter in the tube which absorbs the lower energy photons before they can enter the patient.
d. collision of the electron beam with the tungsten target on the tube anode. - VERIFIED ANSWER✔✔-d
The number of electron that flow from the cathode to the anode in the tube is controlled by the .
a. anode target
b. collimator
c. mA
d. kV - VERIFIED ANSWER✔✔-c
The slip ring on continuous rotation CT scanners:
1. prevents the high voltage cable from winding up
2. allows the exam to commence more rapidly
3. eliminates the need for the reversal of the gantry frame rotation.
a. 1 only
b. 2 only
c. 3 only
d. 1, 2 & 3 - VERIFIED ANSWER✔✔-d
Which of the following is NOT a part of the CT tube?
a. tungsten target
b. collimator
c. rotating anode
d. filament - VERIFIED ANSWER✔✔-b
Which of the following are NOT commonly used on today's commercially available CT scanners?
1. xenon detectors
2. fourth generation scanners
3. continuous rotation
a. 1 only
b. 1 & 2
c. 1, 2 & 3 - VERIFIED ANSWER✔✔-b
Which system components converts the projection attenuation data into the proper digital form for the array
processor?
a. detector
b. photodiode
c. analog to digital converter
d. host computer - VERIFIED ANSWER✔✔-c
,x-ray photons are produced by a fast moving electron:
1. colliding with an atomic nucleus
2. passing close to an atomic nucleus
3. colliding with an electron within an atom and ejecting it
a. 1 only
b. 2 only
c. 3 only
d. 1, 2 & 3 - VERIFIED ANSWER✔✔-d
Which of the following is TRUE regarding solid state detectors?
1. x-ray photons cause the detectors to generate a flash of light
2. they are the detector type used on most CT scanners today
3. they can be used in both third and fourth generation CT systems.
a. 1 only
b. 2 only
c. 3 only
d. 1, 2 & 3 - VERIFIED ANSWER✔✔-d
CT is commonly referred to as al of the following names EXCEPT:
a. computerized axial tomography
b. digital subtraction angiography
c. CAT scan
d. computed tomography - VERIFIED ANSWER✔✔-b
What control does the operator have over the x-ray in the CT exam?
a. the temperature and color of the x-ray can be tuned
b. the energy level and the quantity of x-rays can be selected
c. the volume and tone of the x-ray can be adjusted
d. the phase and frequency of the x-ray can be adjusted - VERIFIED ANSWER✔✔-b
Which of the following statements if TRUE?
1. kV is the voltage potential between the tube cathode and anode while mA ultimately controls the filament
current and, thus, the temperature of the cathode filament.
2. kV controls the energy level of the x-ray photons and mA controls the number of x-ray photons emitted from
the tube.
3. although the kV and the mA affect the operation of the CT x-ray tube, the two parameters have no bearing on
the image quality
a. 1 only
b. 2 only
c. 1 & 2
d. 2 & 3 - VERIFIED ANSWER✔✔-c
Which of the following does NOT affect the quantity of
x-rays that completely penetrates the patient?
1. the distance that the x-ray photons must travel on their course through the patient's body
2. the molecular composition of the tissues through which the x-ray photons pass
3. the type of detector material used
a. 1 only
b. 2 only
c. 3 only
d. 1, 2 & 3 - VERIFIED ANSWER✔✔-c
___made helical imaging possible.
a. Multi-row detector scanners
b. The introduction of second generation scanners
c. The introduction of fourth generation scanners
d. Continuous rotation scanners - VERIFIED ANSWER✔✔-d
Which of the following statements is FALSE regarding the collection of CT data?
,a. long scan times are more desirable b/c they average out motion artifacts
b. the reconstruction process used to create the image occurs in the array processor
c. to collect the complete set of CT data, x-ray must passed through the body at many different angles
d. the detectors measure x-rays which completely penetrate the patient. - VERIFIED ANSWER✔✔-a
Which of the following is a component NOT normally located in the gantry of modern CT system?
a. pre patient collimators
b. solid state detectors
c. array processor
d. x-ray tube - VERIFIED ANSWER✔✔-c
X-rays are used in CT b/c:
a. they are easily produced by the high frequency generator
b. they are less harmful than the heating effects of microwave radiation
c. they penetrate the body according to specific attenuation characteristics of each tissue
d. the FDA imposes no limit on the dose to the patient - VERIFIED ANSWER✔✔-c
X-rays are produced whenever fast moving electrons collide with any form of matter b/c :
1. the electron splits into two x-ray photons of equal energy upon impact with the matter
2. the electron loses kinetic energy which is converted into the emission of an x-ray photon
3. the electron converts the electron it collides with into an x-ray photon
a. 1 only
b. 2 only
c. 3 only
d. 1, 2 & 3 - VERIFIED ANSWER✔✔-b
Bremsstrahlung radiation does NOT include which type of electron activity?
1. collision between an incoming electron and the nucleus of the target atom
2. collision between an incoming electron and an electron in an inner shell of the target atom
3. slowing down of an incoming electron due to the effect of passing close to the positive charge of the nucleus of
the target atom
a. 1 only
b. 2 only
c. 3 only
d. 1, 2 & 3 - VERIFIED ANSWER✔✔-b
The mA determines the :
a. quantity of x-ray photons
b. coefficient of attenuation
c. slice thickness
d. energy level of the x-ray photons - VERIFIED ANSWER✔✔-a
Increased ___ will increase the likelihood that a given x-ray will penetrate a material.
1. kV
2. mA
3. exposure time
a. 1 only
b. 2 only
c. 3 only
d. 1, 2 & 3 - VERIFIED ANSWER✔✔-a
Collimation:
a. is accomplished by electrically blocking x-ray
b. affects the scan time
c. limits the low energy x-ray photons and passes the high energy photons
d. is accomplished by physically blocking x-rays - VERIFIED ANSWER✔✔-d
Scatter radiation is caused by:
a. miscalibrated detector
b. x-rays generated spontaneously in the ambient atmosphere
, c. deflections from the original trajectory of an x-ray photon through the patient
d. improper patient positioning. - VERIFIED ANSWER✔✔-c
Which technology do multi-row detector scanners employ?
a. second generation
b. third generation
c. fourth generation
d. first generation - VERIFIED ANSWER✔✔-b
Which of the following is NOT a function of a PACS system?
a. reconstruction of the image from the raw data
b. long term data storage
c. digital distribution of images
d. image display for the radiologists - VERIFIED ANSWER✔✔-a
Which of the following is TRUE regarding multi-row detector CT scanners?
1. the size of the detectors array along the z direction may be different
2. the attenuation information from adjacent detector arrays may be added together to generate thicker slices
3. all of the detector array may or may not be used
a. 1 only
b. 2 only
c. 3 only
d. 1, 2 & 3 - VERIFIED ANSWER✔✔-d
Which of the following is FALSE regarding CT systems?
1. they are limited to non oblique transverse scanning
2. they cannot generate a straight coronal or sagittal image
3. they have no moving parts.
a. 1 only
b. 2 only
c. 3 only
d. 1, 2 & 3 - VERIFIED ANSWER✔✔-d
Most of the commands from the technologist are received by the :
a. array processor
b. operator's console
c. host computer
d. amplifier - VERIFIED ANSWER✔✔-b
The operator's console may include:
1. monitor
2. keyboard
3.graphic input device
a. 1 only
b. 2 only
c. 3 only
d. 1, 2 & 3 - VERIFIED ANSWER✔✔-d
Which of the following CT scanners design does NOT use an x-ray tube?
a. first generation
b. PET/CT
c. electron beam CT
d. MDCT - VERIFIED ANSWER✔✔-c
Tube interscan delay time refers to:
a. the time between the end of one scan and the start of the next scan during which the tube will cool
b. a quality assurance test performed daily by the technologist
c. the time required for the tube to make a complete 360 revolution about the gantry
d. the length of time required for the production of photons to begin after applying the voltage to the tube -
VERIFIED ANSWER✔✔-a
