Question 1

All of the following apply to computed tomography (CT) except:

Accepted Answer

A)  a computer is used to reconstruct cross-sectional images of the patient. 
B)  mathematical methods are used to reconstruct images. 
C)  X-ray film is used as the detector. 
D)  special detectors are used to detect X-rays that have passed through the patient at multiple angles. 
A)  a computer is used to reconstruct cross-sectional images of the patient. 
B)  mathematical methods are used to reconstruct images. 
C)  X-ray film is used as the detector. 
D)  special detectors are used to detect X-rays that have passed through the patient at multiple angles. C

Question 2

The attenuation used by Hounsfield in his original experiments was:

Accepted Answer

A)  a heterogeneous beam. 
B)  a monoenergetic beam. 
C)  a polychromatic beam. 
D)  a hardened beam. 
A)  a heterogeneous beam. 
B)  a monoenergetic beam. 
C)  a polychromatic beam. 
D)  a hardened beam. D

Question 3

A CT image of 12 bits per pixel means :

Accepted Answer

A)  each pixel can have a total of 4096 shades of gray. 
B)  the matrix is 4096 * 4096. 
C)  the pixel size is 12 mm. 
D)  the voxel size is 12 mm. 
A)  each pixel can have a total of 4096 shades of gray. 
B)  the matrix is 4096 * 4096. 
C)  the pixel size is 12 mm. 
D)  the voxel size is 12 mm. A

Question 4

A limitation of conventional radiography is that it is qualitative rather than quantitative.

Accepted Answer

A) True 
 B)False

Question 5

In which of the following data acquisition methods is a volume of tissue (rather than a single slice) scanned during a single breath-hold?

Accepted Answer

A)  Spiral/helical CT 
B)  Conventional radiography CT 
C)  Conventional CT 
D)  Slice-by-slice CT 
A)  Spiral/helical CT 
B)  Conventional radiography CT 
C)  Conventional CT 
D)  Slice-by-slice CT

Question 6

The second step of data acquisition is scanning.

Accepted Answer

A) True 
 B)False

Question 7

CT is better at recording very small differences in tissue contrast compared to conventional tomography.

Accepted Answer

A) True 
 B)False

Question 8

A spiral or helical beam is used to scan the patient in slice-by-slice data acquisition.

Accepted Answer

A) True 
 B)False

Question 9

The CT number for water is:

Accepted Answer

A)  (-1000). 
B)  (-100). 
C)  0. 
D)  100. 
A)  (-1000). 
B)  (-100). 
C)  0. 
D)  100.

Question 10

Please match the following concepts for each group. All answer selections will be used just once.

-Superimposition of all structures on film

Accepted Answer

A) Radiography 
B) Heterogeneous beam 
C) WW 
D) Conventional tomography 
E) Homogeneous beam
F)Display device
G)Attenuation
H)Data acquisition
I)CT
J)WL 
A) Radiography 
B) Heterogeneous beam 
C) WW 
D) Conventional tomography 
E) Homogeneous beam
F)Display device
G)Attenuation
H)Data acquisition
I)CT
J)WL

Question 11

The limitations of conventional tomography include all of the following except:

Accepted Answer

A)  superimposition of structures above and below the focal plane. 
B)  image blur from movement of the tube and film. 
C)  contrast degradation from the open beam geometry. 
D)  the presence of ghost images on the film. 
A)  superimposition of structures above and below the focal plane. 
B)  image blur from movement of the tube and film. 
C)  contrast degradation from the open beam geometry. 
D)  the presence of ghost images on the film.

Question 12

The photoelectric effect occurs mainly in tissues with a low atomic number.

Accepted Answer

A) True 
 B)False

Question 13

The display FOV can ________________ the scan FOV (sFOV).

Accepted Answer

A)  be greater than 
B)  be less than 
C)  be replaced by 
D)  be reversed by 
A)  be greater than 
B)  be less than 
C)  be replaced by 
D)  be reversed by

Question 14

Please match the following concepts for each group. All answer selections will be used just once.

-Range of CT numbers

Accepted Answer

A) Radiography 
B) Heterogeneous beam 
C) WW 
D) Conventional tomography 
E) Homogeneous beam
F)Display device
G)Attenuation
H)Data acquisition
I)CT
J)WL 
A) Radiography 
B) Heterogeneous beam 
C) WW 
D) Conventional tomography 
E) Homogeneous beam
F)Display device
G)Attenuation
H)Data acquisition
I)CT
J)WL

Question 15

Which of the following best describes the term "data acquisition geometry" in CT?

Accepted Answer

A)  The size and shape of the X-ray beam 
B)  The arrangement of the X-ray tube and detectors 
C)  The stationary ring of detectors 
D)  The rotation of the X-ray tube 
A)  The size and shape of the X-ray beam 
B)  The arrangement of the X-ray tube and detectors 
C)  The stationary ring of detectors 
D)  The rotation of the X-ray tube

Question 16

Please match the following concepts for each group. All answer selections will be used just once.

-Cathode ray tube

Accepted Answer

A) Radiography 
B) Heterogeneous beam 
C) WW 
D) Conventional tomography 
E) Homogeneous beam
F)Display device
G)Attenuation
H)Data acquisition
I)CT
J)WL 
A) Radiography 
B) Heterogeneous beam 
C) WW 
D) Conventional tomography 
E) Homogeneous beam
F)Display device
G)Attenuation
H)Data acquisition
I)CT
J)WL

Question 17

All of the following changes occur in the attenuation of a heterogeneous beam of radiation except:

Accepted Answer

A)  the beam quality. 
B)  the beam quantity. 
C)  the beam intensity. 
D)  the beam direction. 
A)  the beam quality. 
B)  the beam quantity. 
C)  the beam intensity. 
D)  the beam direction.

Question 18

Conversion of the attenuation readings into a CT image is accomplished by reconstruction algorithms.

Accepted Answer

A) True 
 B)False

Question 19

The total number of X-ray transmission measurements is equal to the:

Accepted Answer

A)  total number of detectors. 
B)  number of views in each scan. 
C)  product of the number of views and the number of rays in each view. 
D)  the number of views divided by the number of rays in each view. 
A)  total number of detectors. 
B)  number of views in each scan. 
C)  product of the number of views and the number of rays in each view. 
D)  the number of views divided by the number of rays in each view.

Question 20

The WW controls the image contrast and the WL controls the image brightness.

Accepted Answer

A) True 
 B)False

All of the following apply to computed tomography (CT) except:

The attenuation used by Hounsfield in his original experiments was:

A CT image of 12 bits per pixel means :

A limitation of conventional radiography is that it is qualitative rather than quantitative.

In which of the following data acquisition methods is a volume of tissue (rather than a single slice) scanned during a single breath-hold?

The second step of data acquisition is scanning.

CT is better at recording very small differences in tissue contrast compared to conventional tomography.

A spiral or helical beam is used to scan the patient in slice-by-slice data acquisition.

The CT number for water is:

Please match the following concepts for each group. All answer selections will be used just once. -Superimposition of all structures on film

The limitations of conventional tomography include all of the following except:

The photoelectric effect occurs mainly in tissues with a low atomic number.

The display FOV can ________________ the scan FOV (sFOV).

Please match the following concepts for each group. All answer selections will be used just once. -Range of CT numbers

Which of the following best describes the term "data acquisition geometry" in CT?

Please match the following concepts for each group. All answer selections will be used just once. -Cathode ray tube

All of the following changes occur in the attenuation of a heterogeneous beam of radiation except:

Conversion of the attenuation readings into a CT image is accomplished by reconstruction algorithms.

The total number of X-ray transmission measurements is equal to the:

The WW controls the image contrast and the WL controls the image brightness.

Computed Tomography: an Overview

Digital Image Processing

Data Acquisition Concepts

Image Reconstruction

Iterative Reconstruction Basics

Basic Instrumentation

Image Postprocessing and Visualization Tools

Image Quality

Radiation Dose in Computed Tomography

Multislice Computed Tomography: Physical Principles and Instrumentation

Other Technical Applications of Computed Tomography Imaging: Basic Principles

Three-Dimensional Computed Tomography: Basic Concepts

Positron Emission Tomographyct Petct and Single-Photon Emission Computed Tomographyct Spectct Hybrid Scanners

Computed Tomography of the Head, Cerebral Vessels, Neck, and Spine

Computed Tomography of the Body

Pediatric Computed Tomography

Quality Control for Computed Tomography Scanners

Filters

Exam 3: Physical Principles of Computed Tomography

All of the following apply to computed tomography (CT) except:

The attenuation used by Hounsfield in his original experiments was:

A CT image of 12 bits per pixel means :

A limitation of conventional radiography is that it is qualitative rather than quantitative.

In which of the following data acquisition methods is a volume of tissue (rather than a single slice) scanned during a single breath-hold?

The second step of data acquisition is scanning.

CT is better at recording very small differences in tissue contrast compared to conventional tomography.

A spiral or helical beam is used to scan the patient in slice-by-slice data acquisition.

The CT number for water is:

Please match the following concepts for each group. All answer selections will be used just once. -Superimposition of all structures on film

The limitations of conventional tomography include all of the following except:

The photoelectric effect occurs mainly in tissues with a low atomic number.

The display FOV can ________________ the scan FOV (sFOV).

Please match the following concepts for each group. All answer selections will be used just once. -Range of CT numbers

Which of the following best describes the term "data acquisition geometry" in CT?

Please match the following concepts for each group. All answer selections will be used just once. -Cathode ray tube

All of the following changes occur in the attenuation of a heterogeneous beam of radiation except:

Conversion of the attenuation readings into a CT image is accomplished by reconstruction algorithms.

The total number of X-ray transmission measurements is equal to the:

The WW controls the image contrast and the WL controls the image brightness.

Computed Tomography: an Overview

Digital Image Processing

Data Acquisition Concepts

Image Reconstruction

Iterative Reconstruction Basics

Basic Instrumentation

Image Postprocessing and Visualization Tools

Image Quality

Radiation Dose in Computed Tomography

Multislice Computed Tomography: Physical Principles and Instrumentation

Other Technical Applications of Computed Tomography Imaging: Basic Principles

Three-Dimensional Computed Tomography: Basic Concepts

Positron Emission Tomographyct Petct and Single-Photon Emission Computed Tomographyct Spectct Hybrid Scanners

Computed Tomography of the Head, Cerebral Vessels, Neck, and Spine

Computed Tomography of the Body

Pediatric Computed Tomography

Quality Control for Computed Tomography Scanners

Filters