Geometric Properties
What are the two components of geometric properties?
Detail and distortion
What are the two components of photographic properties?
Contrast and density
15% of the kVp value is equal to ____ kVp or _______ the mAs.
10 kVp; doubling mAs
What are the types of image receptor technology used in CR and DR?
PSP and TFT
What prime factor is increased to reduce patient dose?
kVp
What is considered "true" distortion?
Shape
What is the first technical factor that should be adjusted if an image exposure level is below the exposure index range and quantum mottle is present?
mAs
What are the new technical factors that would reduce patient dose and maintain density using 65 kVp and 4 mAs?
75 kVp and 2 mAs
What technology uses barium fluorohalide with europium?
Photostimulable phosphor
What are examples of beam restriction devices and which is most common?
Aperture, cone, cylinder, manual collimator (most common)
What prime factor should be maximized to reduce distortion?
SID
Which element of display monitors affects contrast resolution?
What are the new technical factors using 70 kVp and 8 mAs to create a shorter scale of contrast and maintained density?
60 kVp and 16 mAs
How is X-ray energy released in the processor of CR?
Stimulated by red laser and releases light.
What are the two types of filtration used in the tube to reduce patient dose?
Inherent and added filtration
What strategies minimize any shape distortion?
Perpendicular CR to IR and object. Object parallel to IR.
What interaction with matter is responsible for creating contrast in an image?
Photoelectric effect
What are the new technical factors if 55 kVp and 3 mAs are used and the density needs to be doubled without changing the contrast scale?
55 kVp and 6 mAs
Fill in the blanks: _______ capture DR uses a scintillation layer made of ________ and a TFT made of ______.
Indirect; cesium iodide (CsI); amorphous silicon (a-Si)
What are 2 examples of techniques that can increase contrast, but also increase patient dose?
Lower kVp and use a grid
Pixel size must ________ and matrix size must ______ to maximize spatial resolution.
Decrease; increase
If kVp is increased from 70 to 80 kVp, what happens to Compton interactions, contrast, and patient dose?
Increases; decreases; and decreases
What are the new technical factors if 85 kVp and 15 mAs are used and the density must be doubled without increasing the patient dose?
95 kVp and 15 mAs
Describe the steps for an image to be processed using direct capture DR.
Which interaction with matter contributes to fog and which contributes to patient dose?
Compton; Photoelectric