Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
167 Cards in this Set
- Front
- Back
|
The radiographic film image is composed of metallic ____ on a polyester base.
|
silver
|
|
|
List the four image quality factors of a radiograph.
|
contrast, density, resolution, distortion
|
|
|
Which specific exposure factor controls the quality or penetrating ability of the x-ray beam?
|
kVp
|
|
|
Exposure time is usually expressed in units of ___.
|
milliseconds
|
|
|
The amount of blackness seen on a processed radiograph is called ____
|
density
|
|
|
The primary controlling factor for the overall blackness on a radiograph is ___
|
mAs
|
|
|
If the distance between the x-ray tube and the IR is increased from 40 to 80 inches, what specific effect will it have on the radiographic density, if other factors are not changed?
|
decrease density to 25 percent
|
|
|
Which term is used to describe a radiograph that has too little density?
|
underexposed
|
|
|
Doubling the mAs will result in _____ the density on the IR image.
|
density
|
|
|
T/F: kV must be altered to change radiographic density on the IR image.
|
false. mAs must change
|
|
|
When IR images, using manual technique settings, are underexposed or overexposed, a minimum change in mAs of ____ is required to make a visible difference in the radiographic density.
|
25-30 percent
|
|
|
According to the anode heel effect, the x-ray beam is less intense on the ___ side of the x-ray tube.
|
anode
|
|
|
To best use the anode heel effect, the thicker part of the anatomic structure should be placed under the ____ end of the x-ray tube.
|
cathode
|
|
|
List three common types of compensating filters.
|
wedge, trough, boomerang
|
|
|
Which type of compensating filter is used commonly for AP projections of the thoracic spine?
|
wedge
|
|
|
Which type of compensating filter permits soft tissue and bony detail of the shoulder to be equally visualized?
|
boomerang
|
|
|
A radiograph of the foot is produced using conventional film-screen cassettes. THe resulting radiograph demonstrates too little density and must be repeated. The orginal exposure was 5 mAs. What mAs is needed to correct the density on the radiograph?
|
10 mAs
|
|
|
The difference in density on adjacent areas of the radiograph defines___.
|
contrast
|
|
|
What is the primary controlling factor for radiographic contrast?
|
kVp
|
|
|
List to two scales of radiographic contrast, and identify which is classified as high contrast and which is low contrast.
|
long scale- low contrast
short scale- high contrast |
|
|
T/F: A 50 kV techinique will produce a high-conrast image.
|
true
|
|
|
T/F: A low-contrast image demonstrates more shades of gray on the radiograph.
|
true
|
|
|
WHich one of the following sets of exposure will result in the least patient exposure and produce long-scale contrast on a PA chest radiographic image?
50 kV, 800 mAs 70 kV, 200 mAs 80 kv, 100 mas 110 kv, 10 mas |
110 kV, 100 mAs
|
|
|
A radiograph of the hand is underexposed and must be repeated. The orginal technique used was 55 kV with 2.5 mAs. The technologist decides to keep the mAs at the same level but change the kV to increase radiographic density. How much of an increase is needed in kV to double the density?
|
8 t0 10 kV increase
|
|
|
If an anatomic part measures great than __ cm, a grid must be used.
|
9
|
|
|
What type of grid cuttoff is created by the situation: The CR and face of grid are not perpendicular.
|
off-level grid cut-off
|
|
|
What type of grid cut-off is created by the situation: The SID is set beyond the focal range of the grid.
|
off-focus grid cut-off
|
|
|
What type of grid cut-off is created by the situation: The back of the grid is facing the x-ray tube.
|
upside down grid cut-off
|
|
|
The recorded sharpness of structures or objects on the radiograph defines _____.
|
resolution
|
|
|
The lack of visible sharpness is called _____.
|
blur or unsharpness
|
|
|
List the three geometric factors that control or influence image resolution.
|
focal spot size, SID, OID
|
|
|
The tern that describes the unsharp edges of the projected image is ____
|
penumbra
|
|
|
T/F: The use of a small focal spot will entirely eliminate penumbra.
|
False
|
|
|
The greatest contributor to image unsharpness as related to positioning is ____.
|
motion
|
|
|
What is the best mechanism to control involuntary motion during an exposure?
|
shorten exposure time
|
|
|
Which one of the following changes will improve image resolution?
|
decrease OID
|
|
|
The technologist is performing an elbow series on a pediatric patient. Because of the nature of the inquiry, the techonologist has been asked to produce radiographs that have the highest degree of recorded resolution possible. Which one of the following sets of factors will produce that level of detail?
|
.3 mm focal spot and 40 in SID
|
|
|
The misrepresentation of an object size or shape projected onto a radiographic recording medium is called _____.
|
distortion
|
|
|
T/F: Through the careful selection and control of exposure and geometric factors, it is possible to eliminate all image distortion.
|
False
|
|
|
List the four primary controlling factors for distortion.
|
OID, SID, object-image receptor alignment, central ray alignment
|
|
|
T/F: A decrease in SID reduces distortion.
|
False. increases distortion
|
|
|
T/F: An increase in OID reduces distortion.
|
False. increases distortion
|
|
|
T/F: Distortion is reduced when the CR is kept perpendicular to the plane of the IR.
|
True
|
|
|
The SID for general radiographic procedures resulting in maximum recorded resolution is:
|
40 inches
|
|
|
A chest x-ray on a patient with an enlarged heart has been requested. Which SID is recommended for this study?
|
72 inches
|
|
|
T/F: Every radiographic image reflects some degree of penumbra or unsharpness, even if the smallest focal spot is used.
|
True
|
|
|
T/F: Image distortion increases as the angle of divergence increases from the center of the x-ray beam to the outer edges.
|
True
|
|
|
The greater the angle of inclination of the object or the IR, the greater the amount of distortion.
|
True
|
|
|
T/F: Central ray alignment has little impact on image distortion.
|
False
|
|
|
T/F: Digital imageing requires that images be chemically processed.
|
False
|
|
|
T/F: Digital images are numeric representation of the x-ray intensities that are transmitted through the patient.
|
True
|
|
|
T/F: Digital iamges viewwed on a monitor are referred to as hard-copies.
|
False
|
|
|
Digital processing involves the systematic application of highly complex mathematical formulas called
|
algorithms
|
|
|
The range or level of image contrast in the digital image is primarily controlled by:
|
digital processing
|
|
|
Exposure latitude with digital imaging is more ___ when compared with film-screen imaging.
|
wide
|
|
|
List the 6 image quality factors specific to digital images.
|
brightness, contrast, resolution, distortion, exposure index, noise
|
|
|
In digital imaging, the term ____ replaces density as applied in IR-screen imaging.
|
brightness
|
|
|
T/F: Changes in mAs will not have a primary controlling effect on digital image brightness.
|
true
|
|
|
T/F: Brightness cannot be altered in the digital image once it has been processed.
|
False
|
|
|
A digital imaging system's ability to distinguish between similar tissues is termed:
|
contrast resolution
|
|
|
Radiographic contrast in the digital image is primarily affected by:
|
application of processing algorithms
|
|
|
The greater the bit depth of a digital imaging system, the greater the:
|
contrast resolution
|
|
|
List the terms describing the two pixel sizes used in digital imaging.
|
acquisition pixel size, display pixel size
|
|
|
Which one of the two pixel sizes is most critical in maintaining high-resolution digital images?
|
acquisition pixel size
|
|
|
T/F: Focal spot size has no impact on the resolution on the digital image.
|
False
|
|
|
The current range of image resolution for digital general radiographic imaging is between:
|
100 to 200 microns
|
|
|
Resolution in the digital image is primarily dependant on:
|
Display capabilities of the monitor
|
|
|
T/F: The factors that affect image distortion for the digital image are different from those that affect film-screen systems.
|
False
|
|
|
A numeric value that is representative of the exposure the digital image receptor receives is termed the _________.
|
exposure index
|
|
|
List the four factors that affect exposure index in the digital image.
|
mAs, kVp, total detector area irradiated, objects exposed
|
|
|
The complete term for "S number," as used by several manufacturers of CR equipment, is _____.
|
sensitivity number
|
|
|
An "S number" is _____ proportional to the radiation exposing the patient; and an exposure index, as used by other manufacturers, is ____ proportional.
|
indirectly, directly
|
|
|
If the recomminded exposure index range for a well-exposed image is between 150 and 250, as "S number" of 350 to 550 would indicate _______ of the image.
|
underexposure
|
|
|
If the recommended exposure index range is between 2.0 and 2.4, an exposure index number of 1.2 would indicated ______ of the image.
|
underexposure
|
|
|
A random disturbance that obscures or reduces clarity is the definition for____
|
noise
|
|
|
SNR is the acronym for the _______.
|
signal-to-noise ratio
|
|
|
When insufficient mAs is applied in the production of a digital image, it will produce a _____ image.
|
low SNR
|
|
|
Another term for image noise is:
|
mottle
|
|
|
Changing or enhancing the electronic image to improve its diagnostic quality is called ______
|
post-processing
|
|
|
Adding text to images
|
annotation
|
|
|
increasing brighness along the edges of structures to increase the visibility of the edges
|
edge enhancement
|
|
|
Reversing the dark and light pixel value of an image- the x-ray image reverses from a negative to a positive
|
image reversal
|
|
|
magnifying all or part of an image
|
magnification
|
|
|
adjusting brightness values of adjacent pixels closer together
|
smoothing
|
|
|
removing background anatomy to allow visualization of contrast media-filled structure
|
subtraction
|
|
|
List the three components of a CR system
|
image plates, IP reader, tech work station
|
|
|
What material on the CR imaging plate captures the latent image?
|
photostimuable phosphors
|
|
|
When using a CR image plate, patient data can be linked to the image by use of a:
|
barcode reader
|
|
|
T/F: Once the CR image plate has had an image recorded on it, it must be discarded.
|
false
|
|
|
T/F: The latent image on a CR image plate is read line by line by a laser within the CR reader.
|
True
|
|
|
It takes approximately 20 seconds to process a CR image and reload the cassette with a clean imaging plate.
|
true
|
|
|
The latent image is erased on the CR image plate by applying:
|
bright light
|
|
|
The process of transferring the CR image to a storage device is termed
|
image archiving.
|
|
|
When using CR, a minimum of __ percent of the IR must be exposed for an accurate exposure index.
|
30
|
|
|
T/F: The use of grids is optional with the CR since the IP is not as sensitive to scatter radiation as film-screen radiography.
|
false
|
|
|
Which of the following imaging components is not required with direct digital radiography?
IP, image reader, grid |
IP or Image reader
|
|
|
T/F: Patient dose may be lower with DR as compared with film-screen radiography and CR.
|
True
|
|
|
T/F: When using DR for most nongrid procedures, one reason the grid is generally not removed is its fragile construction.
|
True
|
|
|
T/F: The 30% collimation rule applies to direct digital radiography.
|
False
|
|
|
24x30 cm
|
10x12 in
|
|
|
18x24 cm
|
8x10 in
|
|
|
35x43 cm
|
14x17 in
|
|
|
30x35 cm
|
11x14 in
|
|
|
24x24 cm
|
9x9 in
|
|
|
35x90 cm
|
14x36 in
|
|
|
T/F: THe size of the IR used is dependant primarily on the size of the body part being examined.
|
True
|
|
|
Define the acronym PACS
|
Picture Archiving Communication System
|
|
|
T/F: A PACS automatically transports conventional x-ray IRs to the chemical processor after they have been exposed.
|
False
|
|
|
DICOM
|
Digital Imaging Communications in Medicine
|
|
|
RIS
|
radiology information system
|
|
|
HIS
|
hospital information system
|
|
|
HL7
|
health care level 7
|
|
|
An electronic, comprehensive database of all patient records and data is referred to as
|
PACS
|
|
|
series of "boxes" that gives form to the image
|
pixel
|
|
|
range of exposure factors that will produce an acceptable image
|
exposure latitude
|
|
|
the user adjusting the window level and window width
|
windowing
|
|
|
unsharp edges of the projected image
|
penumbra
|
|
|
numerical value that is representative of the exposure the IR received in digital radiography
|
exposure index
|
|
|
representative of the number of shades of gray that can be demonstrated by each pixel
|
bit depth
|
|
|
misrepresentation of object size or shape as projected onto radiographic recording media
|
distortion
|
|
|
the energy of the x-ray photon
|
kVp
|
|
|
random disturbance that obscures or reduces clarity
|
noise
|
|
|
the delivery of health care services using telecommunications and computer technology
|
telemedicine
|
|
|
changing or enhancing the electronic image to view it from a different perspective or improve its diagnostic quality
|
post-processing
|
|
|
DR
|
direct digital radiography
|
|
|
AEC
|
automatic exposure control
|
|
|
the user adjecting the window level and window width
|
windowing
|
|
|
representative of the number of shades of gray that can be demonstrated by each pixel
|
bit-depth
|
|
|
random disturbance that obscures or reduces clarity
|
noise
|
|
|
range of exposure factors that will produce an acceptable image
|
exposure latitude
|
|
|
controls the brightness of a digital image (within a certain range)
|
level
|
|
|
a term used by some equipment manufacturers to indicate exposure index
|
sensitivity number
|
|
|
series of "boxes" that give form to the image
|
matrix
|
|
|
Which traditional unit is used to measure radiation exposure in air?
|
Roentgen
|
|
|
Which traditional unit of measurement is used to describe patient dose?
|
RAD
|
|
|
What does the acronym ED stand for?
|
effective dose
|
|
|
What is the whole body ED limit per year for a tech?
|
5 rem or 50 mSv
|
|
|
What is the cumulative dose limit for a 35 year old tech?
|
35 rem or 350 mSv
|
|
|
THe SI unit for Roentgen (R) is:
|
Columbs
|
|
|
The SI unit for Rad is:
|
Grays
|
|
|
The SI unit for REM is:
|
Sieverts
|
|
|
3 rad=___Gy
|
.03
|
|
|
448 mrad=____mGy
|
4480
|
|
|
38 rem=____Sv
|
.38
|
|
|
15 rem=____mSv
|
150
|
|
|
What is the max dose for a pregnant tech per month?
|
.05 rem
|
|
|
What is the max dose for a pregnant tech for the entire gestational period?
|
.5 rem
|
|
|
The ED limit for minors under the age of 18 years is ____ rem per year.
|
.1
|
|
|
Personnel monitoring devices must be worn if there is a possibility of acquiring ___% of the annual occupational ED limit.
|
10
|
|
|
Define TLD
|
thermoluminescent dosimetry
|
|
|
Define OSL
|
optically stimulate luminescence
|
|
|
ALARA means
|
As Low As Reasonably Acheivable
|
|
|
A young child comes to the radiology department for a skull series. The child is combative and will not hold still for the procedure. Who should be askd to restrain the patient?
|
a non pregnant family member
|
|
|
T/F: With accurate and close collimation, area shields do not need to be used.
|
False
|
|
|
T/F: Skin entrance exposure (SEE) has the highest numeric value of all patient doses.
|
true
|
|
|
T/F: In radiography, SEE carries the least biologic significance.
|
True
|
|
|
T/F: ED describes gonadal dose levels only for each radiographic procedure.
|
False
|
|
|
Which is the best method of reducing scatter to a worker's eyes and neck during fluoroscopy?
|
keep the image intensifying tower as close to the patient as possible
|
|
|
Which of the following is the best plae for a tech to stand during fluoro to reduce occupational exposure?
|
behind the radiologist
|
|
|
What is the federal set limit for exposure rates intensified fluoro units?
|
10 rad/min
|
|
|
With most modern fluoro equipment, the average exposure rate is:
|
3 to 4 R/min
|
|
|
What is one of the primary causes for repeat radiographs?
|
poor communication between techs and patients
|
|
|
In addition to communication, what two other factors often lead to repeat exposures?
|
improper techniques and positioning
|
|
|
The ____ chest projection provides the greatest ED for females.
|
AP
|
|
|
_____ patients reveive a greater ED for an AP hip, with or without gonadal shielding.
|
Male
|
|
|
Which specfic organ is each gender receives the greatest dose in AP, PA, and lateral upper GI projections?
|
lungs
|
|
|
Which radiographic procedure listen on the patient dose chart provides the least amount of SEE for males and females?
|
PA chest
|
