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mm). This study also included a questionnaire in which nearly one half of the respondents reported rarely or never wearing their radiation badges. One half of the respondents either had exceeded or did not know whether they had exceeded monthly or quarterly occupational dose limits at some time within the past year. Regarding protection, 30% rarely or never wore a thyroid shield, 73% rarely or never wore lead glasses, 70% rarely or never used a ceiling-mounted lead shield, and 83% rarely or never wore leaded gloves. These results indicate that there can be significant complacency even among the population of physicians who are at the most risk and who have substantial training in radiation safety and physics. In general, the patient is exposed only once. Most of our patients are in an older age range and are therefore less likely to have malignancies. However, because of the long screening times, patients should be evaluated for transient skin erythema, which may present up to several weeks after the procedure, and other skin conditions. Several available devices can help reduce total exposure. A floating table simplifies positional changes and reduces the need for fluoroscopic adjustments. A power injector ensures that an adequate volume of contrast is delivered that maximizes image quality and reduces the need for multiple screening runs. This is especially important when imaging the thoracic or abdominal aorta and its branches. Most important, a power injector allows operators to increase their distance from the source. The same effect can be achieved by adding extension tubing to the catheter injection port during manual injection technique. The tabletop should be maximally radiolucent, and the equipment (stent grafts, guidewires, catheters) should be well marked with radiopaque indicators that are easily visualized. Noninvasive vascular imaging techniques such as duplex Doppler scan and intravascular ultrasound scan do not provide the same anatomic detail as angiography and currently have a limited role in the performance of endovascular procedures. Marking appropriate landmarks on the screen with an erasable pen allows one to work under regular fluoroscopy rather than “road mapping,” which may increase exposure. Summary of results and conclusions Although the exposures measured in our study fall within the ICRP limits established for occupational exposure, they are nonetheless significant, and exposure is cumulative. Factors that increase exposure include increased fluoroscopy time required for the aortounifemoral grafts and the proximity of the surgeon to the operative field of the abdomen and pelvis. Our results indicate that a team of surgeons can perform 386 hours of fluoroscopy per year or 587 EAIA repairs per year and remain within occupational exposure limits. This does not include other endovascular procedures, the performance of which would lower these figures. The maximum allowable occupational and civilian radiation exposure doses have been lowered with time. It is likely that with increasing knowledge about the effects of radiation, this trend will continue. We recommend keeping exposure to within, at most, 10% to 20% of established occupational limits. Those performing these procedures should actively monitor their effective doses and educate personnel on methods for reducing exposure. Discussion Dr Samuel S. Ahn (Los Angeles, Calif). Thank you for the floor. I think Dr Lipsitz and his colleagues at Montefiore deserve many congratulations for bringing this important topic of radiation safety to our attention, and I think the Society program committee also deserves praise for allowing this paper to be presented on the main program. I wish it had been presented in front of a larger audience actually. Without question, this topic
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