Final Exam Flashcards
These systems all use cassettes:
- CR
- DR
- Film Screen
CR and film screen
The backing material in CR cassettes is made of:
aluminum
In CR, this layer keeps the phosphor safe.
protective
In CR, this layer is commonly called the active layer.
phosphor
This element is used as a scintillator in CCD indirect DR systems.
cesium iodide
This element is used as a photoconducter in direct DR systems.
amorphous selenium
This element is used as a photodetector in TFT indirect DR systems.
amorphous silicon
The central part of PACS, this houses both historic and current data.
archive server
T/F - Web-based PACS allow for greater hardware flexibility.
true
The number of pixels contained in a display refers to__.
resolution
____ define how a set of images will be displayed on a monitor
hanging protocols
Which advanced image manipulation function will allow the technologist to join multiple images together as one?
stitching
T/F - The archive is one of the fastest growing PACS components.
true
T/F - The image storage component controls the receipt, retrieval, and distribution of images.
false
T/F - The image manager controls all DICOM processes running within the archive.
true
This is the component that interfaces with RIS and HIS.
image manager
T/F - Image manager is not capable of populating image information in EMR.
false
This is the most common level of RAID.
RAID 5
This is the least expensive form of long-term storage.
DVD
These are also known as film printers.
imagers
A comprehensive set of activities designed to monitor and maintain systems that produce a product.
quality control
A plan for the systematic observation and assessment of the different aspects of a project, service, or facility to make certain that standards of quality are being met.
quality assurance
This level of QC is done prior to installation or after a major repair is completed.
acceptance testing
This level of QC is done in order to ensure equipment is operating as expected and to catch problems before they become apparent radiographically.
routine maintenance
This level of QC is performed when errors in equipment performance are apparent, this level of QC is typically performed by a service rep.
error maintenance
Reject analysis is a __ QC step.
monthly
T/F - CR imaging plates should only be erased once a day, no matter what.
false
T/F - It is okay to throw an old imaging plate away as general trash when they need to be replaced.
false
What type of radiation is used to create the useful parts of a diagnostic image?
exit radiation and remnant radiation
T/F - Beam interactions are not affected by beam quality and quantity.
false
The image contained within the imaging receptor before it is processed into the final image is called the ____ image.
latent
Image formation is the result of_____ absorption.
differential
What are the three form of attenuation?
absorption, scatter, transmission
T/F - The primary beam is what creates digital images.
false
T/F - Ionization is the process through which an atom ejects a neutron, gaining a net charge.
false
In the diagnostic range, absorption occurs through a process called______.
photoelectric effect
T/F - During a photoelectric event, the x-ray photon loses energy, and is able to exit the body.
false
Higher kVp = Less scatter
Lower kVp = More scatter
false
T/F - The x-ray photon does not lose energy during a coherent scatter event.
true
The primary beam is a ______ beam.
heterogenous
During this form of attenuation, the beam passes through the body with no interaction with atomic structures.
transmission
Scatter causes an effect on the final image that is called _______.
fog
In regards to the patient, which of the following impact beam attenuation
- part thickness
- tissue type
- tissue density
all of the above
T/F - Energy level of the beam impacts attenuation.
true
Beam attenuation increases roughly __% for each 4-5 cm of increased tissue thickness.
50%
Tissues comprised of atoms with low atomic numbers present ____ opportunities for scatter or absorption to occur.
less
This is the amount of matter per unit volume.
density
An x-ray beam’s quality is also referred to as it’s ____
penetrability
Absorption is responsible for the ____ color of an image
white
Transmission is responsible for the ____ color of an image
black
Scatter is responsible for the ____ color of an image
grey
T/F - High contrast means the image has a lot of greyscale.
false
T/F - Low contrast means the image is mostly black and white.
false
Less than __% of the primary beam reaches the image receptor
5%
Film-screen, CR, and DR all use cassette-based technology.
false
In terms of dynamic range, a ____ range is preferred.
wide
____ can occur when an image receptor is over exposed.
saturation
Image brightness can be adjusted by adjusting:
window level and exposure factors
These are numeric values that indicate the amount of radiation an image receptor receives.
EI numbers and S numbers
The exhibited difference in brightness levels within an image.
contrast
The absorption characteristics of the tissues being imaged.
subject contrast
T/F - An abdomen has greater subject contrast than a chest.
false
T/F - The quality of a radiographic beam effects the way it may be attenuated.
true
Pixel size =
FOV/matrix size
The term used to evaluate the accuracy of anatomical structural lines.
spatial resolution
T/F - Pixel size is the primary factor that affects spatial resolution.
true
T/F - Spatial frequency has no impact on spatial resolution.
false
T/F - Larger objects have larger spatial frequency.
false
The measurement of how efficiently an image receptor is in converting x-ray exposure it receives into a quality radiographic image.
DQE
Phosphor layers of the PSP can be of two types.
____ means that the crystals are randomly distributed, ____ means that the crystals are columnar, resembling needles standing on end, that are densely packed together
turbid, structured
T/F - When a PSP is irradiated, electrons get trapped in the conduction band, just outside of the valence.
true
CCD/CMOS are used in direct capture methods.
false
This DR component does what a PSP does in CR systems.
scintillator/photodetector
T/F - TFTs are used in direct capture methods.
true
Sampling frequency must be at least ____ times that of input frequency bandwidth.
2
S numbers are ____ proportional
inversely
EI numbers are ____ proportional
directly
____ is the main controller of contrast in film-screen imaging.
kVp
____ is the main controller of contrast in digital imaging
LUT
Scatter, in the diagnostic range, is mostly due to ____.
compton effect
T/F - Collimation and field size are directly proportional.
false
Increasing collimation ____ scatter production.
decreases
Increasing collimation _____ contrast.
increases
T/F - A tightly collimated primary beam uses the same amount of mAs as a poorly collimated primary beam to achieve the same level of exposure.
false
T/F - When increasing collimation, kVp should be increased.
false
T/F - Focused grids can be used at any SID.
false
When going from no grid to a 10:1 grid, you have to multiply your original mAs by ____.
5
When going from no grid to a 5:1 grid, you have to multiply your original mAs by ___.
2
T/F - Using two grids at the same time can cause Moire effect.
true
Fluoroscopy is used to produce ____ images.
dynamic
____ is a hollow air-filled cell connected to a timer circuit via wire.
ionization chamber
T/F - Phototimers are the most commonly used form of AEC today.
false
T/F - Raising kVp when using AEC increases exposure time.
false
T/F - Increasing mA will increase exposure time.
false
In general, backup time should be set to terminate when the exposure has reached ____% of the desired exposure.
150-200
T/F - Collimation has no effect on AEC.
false
When performing QA measures on an AEC system, the system should be able to provide multiple exposures with mR readings with __% of each other.
5
T/F - Exposure technique charts that are based around variable kVp are the best because they do not alter contrast.
false
Amorphous selenium is used in ____.
direct DR
Amorphous silicon is used in ____.
indirect DR
