Distortion

Question 1

what are the 2 factors of size distortion

Answer 1

SID & OID

Question 2

what is the relationship between SID and magnification

Answer 2

inverse relationship
as SID increases MAGNIFICATION decreases (beam diverges less)

Question 3

what is the relationship between OID and MAGNIFICATION

Answer 3

direct relationship
as OID increases MAGNIFICATION increases (beam diverges more)

Question 4

which size SID is used to minimize size distortion

Answer 4

larger SID

Question 5

which OID is used to minimize size distortion

Answer 5

smaller OID

Question 6

what are the 2 types of shape distortion

Answer 6

Elongation
Foreshortening

Question 7

define elongation

Answer 7

image size is longer than object length

stretching the image in 2 directions

Question 8

define foreshortening

Answer 8

image size is shorter than object length

compressing the anatomy in 2 directions

Question 9

off-centering the CR or the part will result in what type of shape distortion

Answer 9

elongates the anatomy

Question 10

what will happen if you off-center the IR

Answer 10

you will clip anatomy not distort the image

Question 11

angling the CR will result in what type of shape distortion

Answer 11

elongates the anatomy

Question 12

Angling the IR results in what shape distortion

Answer 12

elongates the anatomy

Question 13

angling the body part will result in what type of shape distortion

Answer 13

foreshortening the anatomy (AP lordotic chest)

Question 14

is rotating the body part the same as part angling

Answer 14

yes, but its complicated
some anatomy is foreshorten
some anatomy is elongated

Question 15

in most obliques is anatomy elongated or foreshortened

Answer 15

mostly its foreshortened

Question 16

which obliques show no discernible shape distortion

Answer 16

round anatomy structures (knee)

Question 17

define displacement

Answer 17

moving 2 or more anatomical structures away from each other

Question 18

what is the purpose of aligning the CR or rotating/angling the part

Answer 18

to displace anatomical structures

Question 19

what are the 2 ways to create displacement

Answer 19

angling the CR or angling the PART

Question 20

How do you minimize size distortion

Answer 20

Increase SID or Decrease OID

Question 21

how do you minimize shape distortion

Answer 21

part should remain perpendicular to CR and parallel to IR and be properly aligned

Question 22

why must you take separate images on the hip, knee, and ankle

Answer 22

to make sure CR is aligned precisely and to avoid any elongation

Question 23

in a caldwell skull, angling the CR will result in what

Answer 23

elongation and displacement

Question 24

In a caldwell skull, angling the part will result in what

Answer 24

foreshortening and displacement

Question 25

in a caldwell skull, angling the IR will result in what

Answer 25

elongation and no displacement

Question 26

Angling the part and the IR will result in what

Answer 26

elongation and displacement