Chapter 15 Test Flashcards
In radiographic image intensification, the ratio of the number of light photons at the output phosphor to the number of photons at the input phosphor describes:
a.) brightness gain
b.) flux gain
c.) minification gain
d.) conversion factor
b.) flux gain
mAs controls the ____________ of photons in the xray beam
a.) inertia
b.) penetrating power
c.) quality
d.) quantity
d.) quantity
__________ imaging is used to view the human body in real time, accomplished with fluoroscopy as opposed to radiography.
a.) static
b.) still
c.) dynamic
d.) colorized
c.) dynamic
The purpose of the 5 minute timer in fluoroscopy is to:
a.) inform the radiographer of equipment malfunction
b.) alert the radiographer
c.) open the circuit
d.) terminate exposure once the maximum time has been reached
b.) alert the radiographer
A fluoro system equipped with an ABC mechanism with the tube below the table, moving the I.I away from the patient will:
a.) increase the size of the radiation field at the table top
b.) reduce image size of an anatomic structure
c.) decrease patient dose
d.) increase patient dose
d.) increase patient dose
Magnification fluoroscopy is accomplised by:
1.) moving the image intensifier focal point further from the output phosphor
2.) selecting a smaller portion of the input phosphor
3.) decreasing the voltage to the electrostatic focusing lenses
a.) 1 only
b.) 1 and 2 only
c.) 2 and 3 only
d.) 1, 2 and 3
b.) 1 and 2 only
Which of the following will occur if voltage to the electrostatic focusing lenses is increases?
a.) magnification of the image
b.) inversion of the image
c.) reversal of the image
d.) minification of the image
a.) magnification of the image
How does an increase of 25 mAs to 50 mAs affect xray beam quality?
a.) it depends on the focal spot size
b.) decreases quality
c.) it has no effect
d.) increases quality
c.) it has no effect
Which of the following describes how fluoroscopic images are acquired that study human anatomy and function?
a.) real time acquisition
b.) exposures timed with the patients body position
c.) mobile c arm system
d.) single, static exposure using low mA
a.) real time acquisition
The commercial fluoroscope was developed by:
a.) rutherford
b.) edison
c.) newton
d.) einstein
b.) edison
How do modern fluoroscopic systems record images?
a.) digital capture technologies and processing
b.) television and cathode ray tube (CRT) technology
c.) mirror optics and lenses
d.) light tight film magazines
a.) digital capture technologies and processing
Fluoroscopic frame averaging is:
a.) identical to pulsed fluoro
b.) not impacted by fast moving patient anatomy
c.) designed to calculate absorbed dose
d.) a technique that combines video frames
d.) a technique that combines video frames
The photocathode is made of:
a.) cesium iodide
b.) glass substrate
c.) zinc and cadmium
d.) cesium and antimony
d.) cesium and antimony
Aluminim filtration has its greatest effect on:
a.) low energy xray photons
b.) high energy scattered photons
c.) low energy scattered photons
d.) high energy xray photons
a.) low energy xray photons
A loss of brightness around the edge of the fluoroscopic image caused by the curve of the photocathode is:
a.) noise
b.) pincushion appearance
c.) vignetting
d.) magnification
c.) vignetting
Unwanted IR exposure that creates fog is caused by:
Scatter secondary radiation
This part of the image intensifier absorbs light and produces electrons:
a.) input phosphor
b.) output phosphor
c.) photocathode
d.) electrostatic focusing lenses
c.) photocathode
In an indirect capture DR system, the electronic components that is configured in a network of detector elements is the:
a.) charge coupled device (CCD)
b.) photoconductor
c.) thin film transistor (TFT)
d.) scintillator
c.) thin film transistor (TFT)
Which device converts analogue signal into a digital signal?
a.) CCD
b.) ADC
c.) TFT
d.) CMOS
b.) ADC
The output phosphor is made of:
a.) cesium and antimony
b.) zinc and cadmium
c.) cesium iodide
d.) zinc and antimony
b.) zinc and cadmium
Federal law requires an audible ____________ minute timer in fluoroscopy.
a.) 3
b.) 5
c.) 9
d.) 10
b.) 5
The input phosphor is made of:
a.) cesium and antimony
b.) zinc and cadmium
c.) cesium iodide
d.) zinc and columnar crystals
c.) cesium iodide
An IR that has been exposed with insufficient mAs may exhibit what effect?
Noise, Quantam Mottle
The original fluoroscopic image was very:
a.) dim
b.) bright
c.) clear
d.) fuzzy
a.) dim
For a mobile fluoroscopic tube, the distance from the source (xray tube) to the tabletop shall be no more than:
a.) 12 inches
b.) 18 inches
c.) 24 inches
d.) 15 inches
a.) 12 inches
The greatest detail sharpness is obtained by using:
1.) a small focal spot
2.) the longest SID
3.) the smallest OID
4.) longer exposure times
a.) 1 only
b.) 1, 2 and 3
c.) 4 only
d.) 1, 2, 3 and 4
b.) 1, 2 and 3
Which of the following devices acts as a switch to release the electric charge collected by a detector element?
a.) TFT
b.) scintillator
c.) CCD
d.) photodiode
a.) TFT
Which of the following is composed of cesium iodide?
a.) intensifier photocathode
b.) conventional fluoroscopic screen
c.) intensifier output phosphor
d.) intensifier input phosphor
d.) intensifier input phosphor
Amorphus selenium is used as the:
a.) photoconductor for indirect capture DR Imaging
b.) photodetector for indirect capture DR imaging
c.) photoconductor for direct capture DR imaging
d.) photodetector for direct capture DR imaging
c.) photoconductor for direct capture DR imaging
The photocathode is where photoemmision happens.
a.) true
b.) false
a.) true
Amorphus silicon is used as the:
a.) photoconductor for indirect capture DR imaging
b.) photodetector for indirect capture DR imaging
c.) photoconductor for direct capture DR imaging
d.) photodetector for direct capture DR imaging
b.) photodetector for indirect capture DR imaging
Part of a DR system with indirect capture, the light sensitive device that is commonly found in digital cameras is the:
a.) CCD
b.) photoconductor
c.) scintillator
d.) TFT
a.) CCD
For a fixed or stationary fluoroscopic tube, the distance from the source (xray tube) to the tabletop shall be no more than
a.) 12 inches
b.) 15 inches
c.) 24 inches
d.) 18 inches
b.) 15 inches
The process of starting and stopping fluoroscopy using a manual control of exposures is commonly known as:
a.) progressive imaging
b.) low frequency fluoroscopy
c.) conventional fluoroscopy
d.) intermittent fluoroscopy
d.) intermittent fluoroscopy
Appropriate scatter radiation control methods include which of the following?
1.) tight collimation
2.) lead masking at the edge of the exposure field
3.) appropriate use of a grid
4.) lower mA settings
5.) using an air gap method
a.) 1, 2 and 4 only
b.) 1, 2, 3, 4 and 5
c.) 1, 2, 3 and 5 only
d.) 2, 3 and 5 only
c.) 1, 2, 3 and 5 only
Which of the following is a key advantage of flat panel fluoro detectors?
a.) round shape
b.) all answers are correct
c.) flat surface input design
d.) heavier weight
c.) flat surface input design
What part of the image intensifier will attract the electrons and increase their kinetic energy?
a.) output phosphor
b.) input phosphor
c.) accelerating anode
d.) electrostatic focusing lenses
c.) accelerating anode
The newest fluoroscopy systems use a flat panel detector
a.) to record the spot images during fluoroscopy
b.) to record the overhead images following fluoroscopy
c.) in place of the image intensifier
d.) in addition to the image intensifier
c.) in place of the image intensifier
A disadvantage of using magnification mode during image intensified fluoroscopy is:
a.) the image has less resolution
b.) the iamge brightness is inconsistent
c.) the patient receives additional dose
d.) none of the above
c.) the patient receives additional dose
The closer the image intensifier is to the patient, the higher the patient dose will be.
a.) true
b.) false
b.) false
The __________ is bonded directly to the input phosphor.
a.) input phosphor
b.) output phosphor
c.) photocathode
d.) accelerating anode
c.) photocathode
Flat panel detectors for fluoroscopic imaging can be the:
a.) cesium iodide amorphus silicon indirect capture detector
b.) amorphus selenium direct capture detector
c.) amorphous silicon direct capture detector
d.) a and b
d.) a and b
Which of the following would increase the scattered radiation to the operator?
a.) increasing patient exposure
b.) increase distance
c.) decreasing field size
d.) increasing collimation
a.) increasing patient exposure
Which of the following will decrease the production of scatter?
a.) increasing FOV
b.) increasing grid ratio
c.) decreasing mAs
d.) decreasing FOV
d.) decreasing FOV
The input phosphor and photocathode form a flat surface.
a.) true
b.) false
b.) false
As mAs increases, quality:
a.) increases
b.) increases by a factor of 4
c.) is unaffected
d.) decreases
c.) is unaffected
An image demonstrating many brightness levels, or shades of gray, with only slight differences between the levels/shades is said to posses:
1.) long scale contrast
2.) low contrast
3.) short scale contrast
a.) 2 and 3 only
b.) 1 only
c.) 2 only
d.) 1 and 2 only
d.) 1 and 2 only
In mobile fluoroscopy, the closer the image intensifier is to the patient, the higher the patient dose.
a.) true
b.) false
b.) false
The device that receives the remnant beam, converts it into light, and then increases the brightness of that light is the:
a.) charge coupled device (CCD)
b.) spot image device
c.) image intensifier
d.) television monitor
c.) image intensifier
Which of the following matrices would produce the greatest spatial resolution?
a.) 1024 x 1024
b.) 2048 x 2048
c.) 3076 x 3076
d.) 248 x 248
c.) 3076 x 3076
A common site for mobile fluoroscopy is:
a.) in the patients name
b.) in the radiology department
c.) in the nursing home
d.) in the OR
d.) in the OR
Using mag mode with flat panel, digital fluroscopy will do which of the following:
1.) increase patient dose
2.) do nothing or very little to patient dose
3.) increase spatial resolution
4.) do nothing to spatial resolution
a.) 1 and 3 only
b.) 3 only
c.) 1 only
d.) 2 and 4 only
d.) 2 and 4 only
Which of the following is/are associated with magnification fluoroscopy?
1.) increased mA
2.) smaller portion of the input phosphor is used
3.) image intensifier focal point moves closer to the output phosphor
a.) 1, 2 and 3
b.) 2 and 3 only
c.) 1 only
d.) 1 and 2 only
d.) 1 and 2 only
Which of the following is accurate regarding flat panel digital fluoroscopy?
a.) there is no light creation from xray stimulation
b.) fluoroscopic images have less resolution
c.) a digital monitor is required for viewing
d.) the photocathode is less important
c.) a digital monitor is required for viewing
Conventional fluoroscopic millamperage uses what type of milliamperage for continuous fluoroscopy?
a.) low range from 5 to 10 mA
b.) high range from 50 to 1200 mA
c.) low range from 0.5 to 5 mA
d.) high range from 25 to 250 mA
c.) low range from 0.5 to 5 mA
Distortion of the fluoroscopic image that appears as unequal magnification is:
a.) noise
b.) pincushion appearance
c.) vignetting
d.) magnification
b.) pincushion appearance
Converts xrays to light
a.) input phosphor
b.) output phosphor
c.) photocathode
d.) rotating anodes
a.) input phosphor
accelerates electrons toward the output phosphor
a.) input phosphor
b.) output phosphor
c.) photocathode
d.) rotating anodes
d.) rotating anode
converts light to electrons
a.) input phosphor
b.) output phosphor
c.) photocathode
d.) rotating anodes
c.) photocathode
converts electrons to light
a.) input phosphor
b.) output phosphor
c.) photocathode
d.) rotating anodes
b.) output phosphor
uses a psp plate
a.) computed radiography
b.) direct capture
c.) indirect capture
d.) scintillator
e.) photoconductor
f.) photodiode
a.) computed radiography
Absorbs emitted light and creates an electrical charge
a.) computed radiography
b.) direct capture
c.) indirect capture
d.) scintillator
e.) photoconductor
f.) photodiode
f.) photodiode
photoconductor
a.) computed radiography
b.) direct capture
c.) indirect capture
d.) scintillator
e.) photoconductor
f.) photodiode
b.) direct capture
Absorbs xray photons and creates an electrical charge
a.) computed radiography
b.) direct capture
c.) indirect capture
d.) scintillator
e.) photoconductor
f.) photodiode
e.) photoconductor
absorbs xrays photons and emits light
a.) computed radiography
b.) direct capture
c.) indirect capture
d.) scintillator
e.) photoconductor
f.) photodiode
d.) scintillator
CCD
a.) computed radiography
b.) direct capture
c.) indirect capture
d.) scintillator
e.) photoconductor
f.) photodiode
c.) indirect capture
