Q4 10/7 Mon.

Question 0

High kVp

Answer 0

• low contrast
• long gray scale
• many shades of gray
• high scatter

Question 1

kVp

Answer 1

• beam penetrability
• quality of radiation
• primary control of image contrast

Question 2

Low kVp

Answer 2

• high contrast

* short gray scale

Question 3

If skin tissue has a high attenuation coefficient does it appear light or dark on film?

Answer 3

• It would appear light
• it’s more dense
• however it is considered less dense radiographically

Question 4

What is the primary control for density

Answer 4

•mAs

Question 5

Primary control for contrast

Answer 5

•kVp

Question 6

mAs

Answer 6

• controls optical density
• # of X-rays in the primary beam
• quantity
• patient dose
• mA X time= mAs

Question 7

What rule comes in to play with kVp & density

Answer 7

•15 % rule

Question 8

15% rule

Answer 8

• 15% increase in kVp is equal to doubling mAs

* 15% decrease in kVp is equal to half the mAs

Question 9

T/F increasing kVp shortens wavelength, increases penetrability, decreases contrast, increases density

Answer 9

•True

Question 10

Maintaining OD

Answer 10

• when adjusting mAs & kVp you must adjust both to maintain optical density
• what u do yo one side do the opposite to the other side

Question 11

Changing OD

Answer 11

•leave one side alone and change the other side

Question 12

If optical density is the only thing that needs to be changed adjust

Answer 12

•mAs

Question 13

If you need to change optical density & contrast

Answer 13

•Adjust kVp

Question 14

If I had a wiggly patient & my density was good but I want to shorten my time what do I do?

Answer 14

•increase mA only cuz I want to maintain my mAs because I liked my density

Question 15

Reciprocity law

Answer 15

• the OD will be the same if the mAs value is constant

* no matter the time & mA the same mAs will produce the same optical density

Question 16

Decrease in field size

Answer 16

• increases contrast
• decrease in OD
• increase patient dose cuz technique must be increased
• decreases scatter

Question 17

If you change from a small focal spot to a large what happens

Answer 17

• increase in blur

* decrease detail

Question 18

Par speed to high speed system what happens to density/resolution

Answer 18

• density increases
• resolution decreases
• blur increases

Question 19

A change from 40”SID TO 72”SID (density, magnification,blur)

Answer 19

• density decreases
• magnification decreases
• blur decreases

Question 20

Body habitus

Answer 20

• sthenic-strong active
• hyposthenic-thin but healthy
• hypersthenic-usually overweight
• asthenic-small old frail

Question 21

Soft tissue technique

Answer 21

•low kVp & high mAs

Question 22

Increase in mAs will increase ____

& no change in ______

Answer 22

• quantity

* quality

Question 23

Increase in kVp will increase quantity & quality?

Answer 23

•true

Question 24

Distance & mAs do not affect

Answer 24

•quality

Question 25

Effects on X-ray quantity & quality on an increased distance

Answer 25

* quality-none | * quantity-reduced

Question 26

Fast screens & high kVp produces

Answer 26

•Image noise thus reduces contrast