Radiologic Evaluation

how do you view an x-ray?

• as if pt were facing you

  • except chest

• in anatomical position

  • except distal extremities point up

• lateral projection

  • placed so the viewer is seeing the image from the perspective as the x-ray tube

what does INT mean?

limb is internally rotated

what does EXT mean?

limb is externally rotated

what does WTB mean?

pt is standing

what does DECUB?

pt is recombent

what does INSP mean?

pt in state of inspiration

what does EXP mean?

pt in state of expiration

what is regulating the density?

adjusting the amount of blackening

how can you adjust the density?

• current

• exposure time

• current x time = milliamps

• distance

the closer an object is to the ___ ____, the more sharply it is defined.

image recepter

what is elongation?

greater length and larger than the actual structure

what is foreshortening?

shorter than the actual structure and reduced in size (proportionally distorted)

what are the ABCS of radiologic analysis?

A- alignment

B- bone density

C- cartilage spaces

S- soft tissue

what are you looking for when checking alignment?

• size

• shape

• number

what are you looking at when checking bone density?

• general bone density

• textural abnormalities

• local density changes

what is normal findings for bone density?

• contrast between soft tissue and bone shades of gray

• contrast between cortical shell and cancellous center

what are abnormal findings for bone density?

• loss of contrast between bone and soft tissue

• loss of a distinct cortical margin

how do you calculate normal cortical thickness?

a+b = c/2

how do you calculate bone mass index?

a+b/c

what are abnormal findings when looking at bone density?

• thin

• delicate

• coarsened

• lacy

• smudged

• fluffy

what are normal findings when looking at bone density changes?

• normal increases in bone density seen in areas of increased physical stress

• normal increases in bone density as a sign of repair

what are you looking for when looking at cartilage spaces?

• joint space width

• subchondral bone

• epiphyseal plates

what things are we looking for when looking at soft tissues

• muscles

• fat pads and fat lines (not usually seen)

• joint capsules (not usually seen)

• periosteum (not usually seen)

• miscellaneous soft tissue findings

what type of abnormal periosteum is this?

solid

what type of abnormal periosteum is this?

spiculated/sunburst

what type of abnormal periosteum is this?

laminated/onionskin

what type of abnormal periosteum is this?

Codman’s triangle

what miscellaneous things should we look for?

• gas

• calcifications

• foreign bodies