Deck 1: Digital Radiography: An Overview

Question 1

If the radiation exposure is too ____, the film is overexposed and the processed image appears too ____ and the radiologist cannot make a diagnosis from such an image.

A) low; dark
B) high; dark
C) light; light
D) dark; dark

Answer 1

high; dark

Question 2

Other than retrospective analysis, why do vast amount of images generated for the wide range of digital radiology examinations need to be stored?

A) medico-legal purposes
B) training purposes
C) billing purposes
D) reference purposes

Answer 2

medico-legal purposes

Question 3

____ is used to describe the degree of film blackening as a result of radiation exposure, and it can be measured by a densitometer.

A) Chemical processing
B) The film characteristic curve
C) Optical density
D) Film speed

Answer 3

Film speed

Question 4

The major components of PACS include image acquisition devices, a PACS computer, devices called interfaces, and display workstations, all of which are connected and linked to the HIS and RIS through digital communication networks.

Question 5

As a radiation detector, film-screen cannot show differences in tissue contrast less than ____.

A) 5%
B) 10%
C) 15%
D) 20%

Question 6

The film gamma refers to the sensitivity of the film to radiation.

Question 7

The term ____, as used in this book, refers to projection radiography, whereby computers process data collected from patients using special electronic detectors that have replaced the X-ray film cassette.

A) filmless imaging
B) digital radiography
C) film-screen radiography
D) digital mammography

Question 8

The output of computer processing, or the ____, must first be converted into an analog signal before it can be displayed on a monitor for viewing by the observer.

A) digital data
B) binary digit
C) digital image
D) digital processor

Question 9

A digital fluoroscopy system consists of very few of the imaging components found in a conventional fluoroscopic imaging system.

Question 10

In order to change a(n)____ (optical range and contrast), an additional set of exposure technique factors must be used, thus increasing the dose to the patient from repeated exposures.

A) display medium
B) film screen
C) spatial resolution
D) image display

Question 11

The ____ refers to the sensitivity of the film to radiation.

A) film speed
B) OD
C) fog density
D) film density

Question 12

Which major technical component of a digital radiography system refers to the collection of X-rays transmitted through the patient?

A) image display
B) post processing
C) image storage
D) data acquisition

Question 13

As a radiation detector, film-screen cannot show differences in tissue contrast less than 30%.

Question 14

For radiography, which of the following is the highest of all the other imaging modalities, and can range from 5 -15 line pairs/mm?

A) spatial resolution
B) film-screen
C) contrast resolution
D) optical range

Question 15

Digital radiography imaging modalities include communication radiography (CR), flat-panel digital radiography (DR), digital mammography (DM), and digital fluorescence (DF)and the laser film digitizer.

Question 16

For digital radiography, special electronic (digital)detectors are used that replace the X-ray film cassette used in film-based radiography.

Question 17

Film-screen radiography has been the workhorse of radiology ever since the discovery of X-ray by W.C.Roentgen in 1895.

Question 18

The purpose of image compression is to increase storage space and decrease the image transmission time.

Question 19

A high-end computer is the heart of the PACS system.

Question 20

The digital detector output signal is linear with the input radiation exposure.

Question 21

Film-based imaging is limited in its ____________________.

Question 22

While DICOM is concerned primarily with images from the digital image acquisition modalities, HL-7 is concerned mainly with textual information from the ____ and ____.

A) HIS; RIS
B) CCD; HIS
C) PACS; RIS
D) CCD; PACS

Question 23

While the RIS and HIS handle essentially textual information, specifically dealing with business operations for the entire hospital, the PACS handle images generated by the various ____________________.

Question 24

The wide exposure latitude of the ____ will produce acceptable images even when the input exposure is low or high.

A) charge-coupled device
B) digital detector
C) digital image
D) light guide

Question 25

One of the major problems with the ____________________ process is poor image quality if the initial radiation exposure has not been accurately determined.

Question 26

As a display medium, the optical range and contrast for film are ____________________ and limited.

Question 27

The detector in digital fluoroscopy is also the ____, since it captures the radiation passing through the patient.

A) TV camera tube
B) digital subtraction tube
C) optic tube
D) image intensifier tube

Question 28

In the production of film-based radiographic images, X-rays pass through the patient and fall upon the film to form a(n)____________________.

Question 29

An important element of image and data communications is that of ____________________.

Question 30

Which of the following is one important objective descriptor of digital image quality?

A) DQE
B) PMT
C) CCD
D) IP

Question 31

Quality assurance and ____ procedures are effective strategies to ensure continuous quality improvement of a product.

A) ALARA
B) CR
C) QC
D) IT

Question 32

The conversion of analog signals into digital data is the function of the ____________________.

Question 33

Image and data communications are concerned with the use of computer communication networks to transmit images from the acquisition phase to the display/viewing and ____________________.

Question 34

Since the PACS contains confidential patient data and information, it is essential that they be secured; hence, ____ is of central importance in a digital hospital as well as in a PACS environment.

A) image security
B) diagnostic
C) interface security
D) data security

Question 35

Which digital radiography modality requires a great deal of special technical considerations in order to detect breast cancer?

A) digital mammography
B) digital fluoroscopy
C) conventional fluoroscopy
D) film-screen mammography

Question 36

Which of the following involves the use of computer technology coupled with communications technology to solve problems in society, including medical imaging and health care?

A) IT
B) MII
C) QC
D) CR

Question 37

Which of the following serve to display images on a monitor for the purpose of image interpretation?

A) PACS
B) IMACS
C) softcopy workstations
D) laser optical disks

Question 38

The film contrast can be described by what is popularly known as the ____________________ or the Hurter-Driffield (H and D)curve.

Question 39

Which of the following makes use of photostimulable or storage phosphors to produce digital images using existing X-ray imaging equipment?

A) DF
B) DM
C) DR
D) CR

Question 40

A major drawback of CR systems is their limited ability to image detail, also known as ____________________.

Question 41

The application of digital image processing to fluoroscopy is referred to as ____________________.

Question 42

The application of information technology to medical imaging is referred to as ____________________.

Question 43

The digital detectors used in CR and flat-panel digital radiography have a characteristic response to radiation exposure that is fundamentally different to the ____________________.

Question 44

While radiography produces static images, fluoroscopy produces dynamic images acquired in real time to allow for the study of motion of organ systems and ____________________.

Question 45

A major feature of workstations is that they allow users to perform digital post processing of images for the purpose of enhancing ____________________.

Question 46

One of the significant differences between CR and film-screen radiography is that the exposure latitude of CR is about 104 times wider than that of the widest range of ____________________.

Question 47

The application of digital fluoroscopy to angiography is referred to as ____________________.

Question 48

Direct conversion digital radiography systems use detectors that convert X-rays directly into ____________________.

Question 49

Two standards that are currently used in a PACS environment are the DICOM and ____________________.

Question 50

To be effective and efficient in ensuring the integrity of the PACS, technologists must not only educate themselves in all aspects of IT but also continue to learn more about the digital world of radiology, including ____________________.