An IR that is large enough to extend at least 1 inch (2.5 cm) beyond the elbow and wrist joints for a forearm projection is
A) needed to record the elbow and wrist on the image.
B) needed so the beam can be tightly collimated.
C) not a required positioning procedure.
D) needed only when a joint problem is suspected.

Question

Quizplus · Accepted Answer

Using an IR that extends at least 1 inch beyond the elbow and wrist joints is necessary to ensure that the entire forearm, including the elbow and wrist joints, is captured on the image. This is a required positioning procedure for a forearm projection. Using a larger IR may also allow for better collimation, but that is not the primary reason for the larger size. The use of a larger IR is not necessary only when a joint problem is suspected, but for all forearm projections.

An IR That Is Large Enough to Extend at Least