Exposure of radiologists during special procedures.

During special procedures, radiologists may receive substantial radiation exposure, especially to the unprotected lens of the eye: 92% of a radiologist's exposure at arteriography is due to radiography at the time of contrast medium injection. The mean lens exposure per exam is 5.8 mR for cerebral and 27.1 mR for abdominal arteriograms. Unshielded by the lead apron, a front-collar film badge overestimates lens exposure by 20% for cerebral and underestimates by 20% for abdominal arteriograms. Since most exposure occurs during contrast medium injection, manual injection should be avoided whenever possible.