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Beam Restriction
Beam Restriction Study Sheet
Question | Answer |
---|---|
What is the best way(s) to reduce the amount of scatter reaching the film? | By restricting the x-ray beam and by using a grid. |
What 2 factors affect the amount of scatter radiation produced? | kVp and irradiated material (patient thickness) |
Name the 4 types of beam restrictors. | Aperture diaphragm, cones, cylinders, and collimators (ACCC) |
What is another name for automatic collimators? | Positive beam limitation devices (PBL) |
X-ray beam and light should coincide within ___ of SID. | 2% |
The principal factors that affect the amount of scatter produced are? | Kilovotage and the irradiated material |
As kilovotage increase, the percentage of x-rays that undergo a Compton interaction __________ and the percentage of photons that undergo photoelectric absorption _________. | Increases, decreases |
The total number of photons that undergo interaction __________ with increased kVp. | Decreases |
When the beam is restricted, _______ scatter radiation will reach the IR, and as a result, technical factors may need to be ________. | Less, increased |
Cones and cylinders are most commonly employed in radiography of the ________, _______, ___________, and ____________. | Skull, spine, gallbladder, breast |
_________ _________ ____________ devices are automatic collimators that use sensing devices to activate collimator shutters into proper position. | Positive beam limitation |
Higher atomic number materials attenuate a ________ percentage of the beam than low atomic number materials. | Greater |
__________ is the quantity of matter per unit of volume measured in kilograms per cubic meter. | Density |
________ __________ is the degree of differential absorption resulting from the differing absorption characteristics of the tissues in the body. | Subject contrast |