EX5 - Shape Distortion

the misrepresentation of the true shape of the image as compared to the object

shape distortion

what are the three types of shape distortion

foreshortening, elongation, spatial distortion

what the three reasons for shape distortion

x-ray beam, position of the image receptor, position of the part

what is the ideal relationship that creates the least amount of shape distortion

the set-up of image receptor, CR, and object that creates the least amount of shape distortion

the _____ is cone shaped with the straightest part of the beam (CR) right in the middle

beam

the ______ needs to be placed so the object is parallel and the CR is perpendicular

image receptor

the _____ or area of interest is the body part you are trying to image

object

the ideal relationship requires that the object is _______ to the image receptor

parallel

the ideal relationship requires that the CR is _______ to the image receptor

perpendicular

the ideal relationship requires that the CR is ______ to the object

perpendicular

the ideal relationship requires that the CR is over the ______ of the object

center

________ is created when the object is angled but the CR remains perpendicular to the IR

foreshortening

when foreshortening occurs, it appears

squashed, flatter

a bone fracture is _______ when foreshortening is seen on an image

hidden

foreshortening produces unequal ________ of object parts

magnification

to avoid foreshortening, place the CR ______________ to the object even if the CR is not perpendicular to the IR

perpendicular

when the object is parallel to the IR but the CR is angled, this explains....

elongation

elongation can also be when the object is not parallel to the IR, but the CR is _____ to the object

perpendicular

elongation makes the image appear to be ______

stretched out or thinner

elongation can remove ______ of parts and used for _____ views

superimposition; axial

What are two axial views that can produce superimposition from elongation?

Sigmoid colon and clavicle

With elongation, the CR should be kept _____ the area of interest

under

regarding elongation, placing the CR directly over the area of interest will _____ shape distortion

minimize

what is it called when the CR is at an angle but the object and the IR are parallel to each other

spatial distortion

the appearance of spatial distortion creates ____

distortion of 3D relationship

spatial distortion makes parts on top of each other appear _______

seperate

what produces stretched out or thinner images

spatial distortion

parts appear ______ from one another from spatial distortion

furtheraway

the relocation on an image is

spatial distortion

The further a part is from the IR, the more ________ it will appear

magnified

an object with a large OID will appear to ______ on the image, in the same direction as the ______

move; CR angle

how do you fix foreshortening on an image

place the CR perpendicular to the object

what is superimposition

when parts are overlapping