RTE2457 ImagingII

_____ - Misrepresentation of the size of an object being examined

The 2 types of distortion are?
____ - enlargement of an object on an image
____ - misrepresentation of the shape of an object on an image

The 2 controlling factors that affect size distortion are?

SID

Due to the divergent property of x-ray photons, only ____ as a type of size distortion is possible. (_____ not possible!)

The relationship between SID & magnification is ______.

OID

Due to the divergent property of x-ray photons, only _____ as a type of size distortion is possible. (Minimization not possible)

The relationship between OID & magnification is _____.

Although both SID & OID control magnification, ____ has a greater effect on size distortion.

Part Thickness & Magnification

A thicker body part will _____ the OID

Best means of minimizing size distortion: use a far ___ & close ___!

SOD - Source to Object Distance
The distance from source of radiation to object.
SOD + ___ = ___

Calculating Size Distortion 
M = SID/SOD

Types of Shape Distortion
____ - object appears longer than its true size
____ - object appears shorter than its true size

Factors that Affect Shape Distortion

Controlling factors
____ - CR, part, IR
____ - direction & degree

CR Alignment
___ - the theoretical center of the x-ray beam where photons exit the focal spot

—- Because an x-ray beam diverges, only the ___ is truly perpendicular

—- The further away the anatomy is from the CR, the greater the __________.

Anatomical Part Alignment

Any body part not perpendicular to the CR or not parallel to the IR will have a greater degree of ______

As CR, Part, and/or IR alignment increases, shape distortion ____

As CR, Part, and/or IR alignment decreases, shape distortion ____

Angulation (Degree)

As beam angulation increases, shape distortion _____
As beam angulation decreases, shape distortion
_____