Question 1

The snapshot of all the transmission measurements at a specific location is the

Accepted Answer

A)  view 
B)  ray 
C)  profile 
D)  all of these 
A)  view 
B)  ray 
C)  profile 
D)  all of these

Question 2

The collimator found between the patient and the detectors is the

Accepted Answer

A)  prepatient collimator 
B)  postpatient collimator 
C)  bowtie filter 
D)  prepatient collimator and postpatient collimator 
A)  prepatient collimator 
B)  postpatient collimator 
C)  bowtie filter 
D)  prepatient collimator and postpatient collimator

Question 3

A pitch of 1 indicates that with each rotation of the tube

Accepted Answer

A)  the table is moving farther than the slice thickness 
B)  the table is moving less than the slice thickness 
C)  the table is moving the same distance as the slice thickness 
D)  none of these 
A)  the table is moving farther than the slice thickness 
B)  the table is moving less than the slice thickness 
C)  the table is moving the same distance as the slice thickness 
D)  none of these

Question 4

For single-slice CT, this collimator controls the slice thickness

Accepted Answer

A)  prepatient collimator 
B)  postpatient collimator 
C)  bowtie filter 
D)  prepatient collimator and postpatient collimator 
A)  prepatient collimator 
B)  postpatient collimator 
C)  bowtie filter 
D)  prepatient collimator and postpatient collimator

Question 5

An image with a WW of 600 and a WL of -300 produces an image that displays pixels with CT numbers ranging from

Accepted Answer

A)  -300 to 600 
B)  -600 to 0 
C)  -300 to 300 
D)  -100 to -300 
A)  -300 to 600 
B)  -600 to 0 
C)  -300 to 300 
D)  -100 to -300

Question 6

The range of CT numbers visible in the CT image is determined by the

Accepted Answer

A)  window level 
B)  window height 
C)  window width 
D)  window clearance 
A)  window level 
B)  window height 
C)  window width 
D)  window clearance

Question 7

The edge enhancement and smoothing filters change the visibility of noise and the spatial resolution.

Accepted Answer

A) True 
 B)False

Question 8

With multislice CT, additional rows of detectors are added along the

Accepted Answer

A)  W-axis 
B)  X-axis 
C)  Y-axis 
D)  Z-axis 
A)  W-axis 
B)  X-axis 
C)  Y-axis 
D)  Z-axis

Question 9

A pitch of 2 indicates that with each rotation of the tube

Accepted Answer

A)  the table is moving farther than the slice thickness 
B)  the table is moving less than the slice thickness 
C)  the table is moving the same distance as the slice thickness 
D)  none of these 
A)  the table is moving farther than the slice thickness 
B)  the table is moving less than the slice thickness 
C)  the table is moving the same distance as the slice thickness 
D)  none of these

Question 10

The grainy appearance of a CT image that is due to the random variations of CT numbers is

Accepted Answer

A)  noise 
B)  spatial resolution 
C)  contrast resolution 
D)  all of these 
A)  noise 
B)  spatial resolution 
C)  contrast resolution 
D)  all of these

Question 11

Based on the Hounsfield scale, the CT number of air is

Accepted Answer

A)  -1000 
B)  0 
C)  1000 
D)  None of these 
A)  -1000 
B)  0 
C)  1000 
D)  None of these

Question 12

This scanner uses a wide fan beam and a fixed array of detectors that encircle the patient.

Accepted Answer

A)  First generation 
B)  Second generation 
C)  Third generation 
D)  Fourth generation 
A)  First generation 
B)  Second generation 
C)  Third generation 
D)  Fourth generation

Question 13

The beam-hardening artifact can be reduced by

Accepted Answer

A)  setting a lower mA 
B)  using a computer algorithm 
C)  increasing the matrix 
D)  increasing the pitch 
A)  setting a lower mA 
B)  using a computer algorithm 
C)  increasing the matrix 
D)  increasing the pitch

Question 14

This CT scanner took approximately 5 minutes to produce a single image.

Accepted Answer

A)  First generation 
B)  Second generation 
C)  Third generation 
D)  Fourth generation 
A)  First generation 
B)  Second generation 
C)  Third generation 
D)  Fourth generation

Question 15

The matrix of CT numbers is the

Accepted Answer

A)  array processor 
B)  algorithm 
C)  filtered back projection 
D)  image data 
A)  array processor 
B)  algorithm 
C)  filtered back projection 
D)  image data

Question 16

To focus on dose optimization, it is important to balance reductions in patient dose with

Accepted Answer

A)  maintaining examination cost 
B)  maintaining image quality 
C)  increasing scan time 
D)  all of these 
A)  maintaining examination cost 
B)  maintaining image quality 
C)  increasing scan time 
D)  all of these

Question 17

How will a pixel with a CT number of 250 appear if the WW is 200 and the WL is 50?

Accepted Answer

A)  Black 
B)  White 
C)  Gray 
D)  It is impossible to say 
A)  Black 
B)  White 
C)  Gray 
D)  It is impossible to say

Question 18

The Z axis for CT scanning goes from

Accepted Answer

A)  side to side 
B)  head to foot 
C)  back to front 
D)  none of these 
A)  side to side 
B)  head to foot 
C)  back to front 
D)  none of these

Question 19

What is the relationship between the number of detector rows in MSCT and radiation dose?

Accepted Answer

A)  direct 
B)  direct proportional; 
C)  inverse 
D)  inverse proportional 
A)  direct 
B)  direct proportional; 
C)  inverse 
D)  inverse proportional

Question 20

A change in any factor that has more x-ray photons reaching the detector will result in an image with decreased

Accepted Answer

A)  noise 
B)  spatial resolution 
C)  contrast resolution 
D)  All of these 
A)  noise 
B)  spatial resolution 
C)  contrast resolution 
D)  All of these

The snapshot of all the transmission measurements at a specific location is the

The collimator found between the patient and the detectors is the

A pitch of 1 indicates that with each rotation of the tube

For single-slice CT, this collimator controls the slice thickness

An image with a WW of 600 and a WL of -300 produces an image that displays pixels with CT numbers ranging from

The range of CT numbers visible in the CT image is determined by the

The edge enhancement and smoothing filters change the visibility of noise and the spatial resolution.

With multislice CT, additional rows of detectors are added along the

A pitch of 2 indicates that with each rotation of the tube

The grainy appearance of a CT image that is due to the random variations of CT numbers is

Based on the Hounsfield scale, the CT number of air is

This scanner uses a wide fan beam and a fixed array of detectors that encircle the patient.

The beam-hardening artifact can be reduced by

This CT scanner took approximately 5 minutes to produce a single image.

The matrix of CT numbers is the

To focus on dose optimization, it is important to balance reductions in patient dose with

How will a pixel with a CT number of 250 appear if the WW is 200 and the WL is 50?

The Z axis for CT scanning goes from

What is the relationship between the number of detector rows in MSCT and radiation dose?

A change in any factor that has more x-ray photons reaching the detector will result in an image with decreased

Introduction to the Imaging Sciences

Structure of the Atom

Electromagnetic and Particulate Radiation

The X-Ray Circuit

The X-Ray Tube

X-Ray Production

X-Ray Interactions With Matter

Image Production

Image Quality and Characteristics

Digital Image Receptors

Radiographic Exposure Technique

Scatter Control

Exposure Technique Selection

Film-Screen Imaging

Fluoroscopic Imaging

Additional Equipment

Filters

Exam 17: Computed Tomography

The snapshot of all the transmission measurements at a specific location is the

The collimator found between the patient and the detectors is the

A pitch of 1 indicates that with each rotation of the tube

For single-slice CT, this collimator controls the slice thickness

An image with a WW of 600 and a WL of -300 produces an image that displays pixels with CT numbers ranging from

The range of CT numbers visible in the CT image is determined by the

The edge enhancement and smoothing filters change the visibility of noise and the spatial resolution.

With multislice CT, additional rows of detectors are added along the

A pitch of 2 indicates that with each rotation of the tube

The grainy appearance of a CT image that is due to the random variations of CT numbers is

Based on the Hounsfield scale, the CT number of air is

This scanner uses a wide fan beam and a fixed array of detectors that encircle the patient.

The beam-hardening artifact can be reduced by

This CT scanner took approximately 5 minutes to produce a single image.

The matrix of CT numbers is the

To focus on dose optimization, it is important to balance reductions in patient dose with

How will a pixel with a CT number of 250 appear if the WW is 200 and the WL is 50?

The Z axis for CT scanning goes from

What is the relationship between the number of detector rows in MSCT and radiation dose?

A change in any factor that has more x-ray photons reaching the detector will result in an image with decreased

Introduction to the Imaging Sciences

Structure of the Atom

Electromagnetic and Particulate Radiation

The X-Ray Circuit

The X-Ray Tube

X-Ray Production

X-Ray Interactions With Matter

Image Production

Image Quality and Characteristics

Digital Image Receptors

Radiographic Exposure Technique

Scatter Control

Exposure Technique Selection

Film-Screen Imaging

Fluoroscopic Imaging

Additional Equipment

Filters