Prime Factors/Tech Chart
Receptor Exposure
Contrast
Spatial Resolution
Distortion
100
kVp
What is the prime factor that controls the speed of the electrons from the cathode to the anode?
100
Quantum Mottle
What is the grainy image caused by underexposure or due to low mAs or kVp?
100
Long scale contrast
What scale of contrast produces many shades of gray?
100
Unit of resolution
What is line pairs/mm
100
Two types of distortion
What are size and shape?
200
mA
What is the amount of electrons flowing between the cathode and anode?
200
Cathode Side
What diode should be placed under the thicker part of the patient to average out the exposure?
200
Two types of contrast
What are receptor contrast and subject contrast?
200
Small pixels and large matrix
What will produce increased resolution?
200
Factors that will decrease size distortion
What are decreased OID and increased SID
300
Inverse Square Law
What is the law that states the intensity of radiation is inversely proportional to the distance?
300
Beam restrictors and grids
What two factors affect scatter reaching the IR?
300
Increased kVp and Increased filtration
What will create a longer scale of contrast?
300
2 types of motion
What are voluntary and involuntary motion?
300
Two types of shape distortion
What are elongation and foreshortening?
400
Relationship between mAs and SID
What is direct?
400
15% Rule
What rule states that if kV is increased 15%, receptor exposure will double?
400
CNR
What is contrast to noise ratio?
400
Highest spatial resolution possible
What is the Nyquist Frequency?
400
Three factors to be aligned to avoid shape distortion
What are CR perpendicular to IR; Tube, part and IR parallel; and CR centered to part and IR?
500
Fixed kVp technique chart
What chart uses optimum kVp to determine kVp levels?
500
Decrease field size and increased grid ratio
What will decrease receptor exposure?
500
Contrast resolution
What is the ability to distinguish between differences in intensity in an image?
500
Number of times spatial frequency should be sampled
What is twice?
500
Distortion that occurs when objects are superimposed causing an object to be magnified
What is spatial distortion?
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