Would you collimate an image retrospectively?

Would you collimate an image retrospectively?

• A. Only in cases of collimation failure. As it is a legal requirement not to cover up exposures to radiation.
• B. Also to reduce the veil glare on images
• C. It is not allowed to collimate after imaging
• D. It should be done routinely for all images

Answer: (A)

Collimation defines the actual exposure field during the radiographic procedure, and the image should truthfully represent that field. Altering the displayed field after the image is acquired would hide part of the exposure, misrepresent the dose delivered, and violate safety and legal standards. Therefore retrospective collimation is not routine. It would only be considered if there was a collimation failure during the original exposure, in which case the proper step is to redo the exam with correct collimation rather than masking or cropping to hide the error.

Collimation defines the actual exposure field during the radiographic procedure, and the image should truthfully represent that field. Altering the displayed field after the image is acquired would hide part of the exposure, misrepresent the dose delivered, and violate safety and legal standards. Therefore retrospective collimation is not routine. It would only be considered if there was a collimation failure during the original exposure, in which case the proper step is to redo the exam with correct collimation rather than masking or cropping to hide the error.