Test 3 Review

Question 1

film’s overall darkness

Answer 1

density

Question 2

density is primarily controlled by

Answer 2

mAs. mA X s. increase either factor and increase density

Question 3

50% mAs reciprocal rule

Answer 3

double the mAs to make film darker, cut in half to make lighter.

Question 4

increased density

Answer 4

too dark

Question 5

decreased density

Answer 5

too light

Question 6

factors that affect density

Answer 6

patient size, SID/FFD, kVp, Screens, Developing, Filtration

Question 7

patient size

Answer 7

the larger the patient, the more mAs needed due to the increase of tissue thickness

Question 8

SID/FFD

Answer 8

an increase in distance results in a decrease in density (rule of 3)

Question 9

kVp

Answer 9

increase in kVp results in increase in density (more scatter is produced)

Question 10

how does scatter affect film

Answer 10

scatter shows up as shades of gray and each shade of gray contributes to the level of darkness, directly affecting the amount of darkness on a film

Question 11

kVp 15% rule

Answer 11

increase kVp by 15% (or 10) increases film density. decreasing it decreases density

Question 12

200 speed screen

Answer 12

crystals are smaller thus requiring more mAs to take them.

Question 13

400 speed screen

Answer 13

crystals are larger. dont need as much mAs to take them

Question 14

grids

Answer 14

used to clean up scatter by taking away levels of gray. must increase mAs.

Question 15

developing

Answer 15

too much developer or too much time in developer = increased density.

Question 16

filtration

Answer 16

used to even out radiographic density. used when xraying something that has two different densities to keep the thin part from burning up. if used incorrectly, it will reduce density on the think part and cause the thin part to burn out

Question 17

contrast

Answer 17

varying shades of gray. controlled by kVp.

Question 18

scatter

Answer 18

undesirable grays on the film making it non diagnostic

Question 19

long scale

Answer 19

low contrast. very dull and gray. results in using too much kVp.

Question 20

short scale

Answer 20

high contrast. very black and white film. result of using low kVp.

Question 21

when do you use a grid

Answer 21

more than 10cm or 75kVp. the higher the grid ratio, the better it works. reduces radiographic density.

Question 22

detail

Answer 22

How well represented the anatomy is radiographically. The crispness of the radiograph, the definition of the radiograph

Question 23

SSD/FID

Answer 23

72” = best detail, the closer the tube to the object there will be an increase in magnification thus the image will not be well defined.

Question 24

OFD

Answer 24

If the part is not as close to the film as possible there will be magnification and that destroys detail. The part is not truly demonstrated.

Question 25

factors affecting detail

Answer 25

SID/FFD, OFD, denity, long scale, increased developer, tube tilt

Question 26

tube tilt

Answer 26

Wrong tube tilt results in loss of detail, or no tube tilt when one is required results in loss of detail.