Question

When radiographing a cross-table lateral hip or axial shoulder using CR, one method of creating a collimation margin at the bottom of the radiograph is to:

A.
Use a narrow lead strip at the bottom edge of the IP, but out of the anatomy
B.
Only one collimation margin is necessary, so this would not be necessary
C.
Make two exposures with suspended respiration; one for the uppermost anatomy, then a second for the dependent anatomy
D.
Expose the anatomy as is and use the post-processing cropping feature

Answer 1

To create a collimation margin at the bottom of a cross-table lateral hip or axial shoulder radiograph, a narrow lead strip should be placed at the bottom edge of the IP but outside the scanned anatomy. This method helps improve image quality by reducing scatter radiation, which is essential in radiographic imaging.

Step-by-step explanation:

When radiographing a cross-table lateral hip or axial shoulder using Computed Radiography (CR), to create a collimation margin at the bottom of the radiograph, one method is to use a narrow lead strip at the bottom edge of the Image Plate (IP), but out of the way of the anatomy being imaged. This helps define the edge of the radiation field and improves image quality by reducing scatter radiation. It is essential when performing radiographic procedures to ensure proper collimation to avoid unnecessary radiation exposure and improve image quality. Using the post-processing cropping feature is not advisable as it does not prevent scatter radiation from affecting the image and increases patient dose unnecessarily. Proper collimation should be done before exposure. Making two exposures with suspended respiration for different parts of the anatomy, as mentioned in option C, is also not the standard practice for creating a collimation margin.