Endovascular abdominal aortic aneurysm repair: methods of radiological risk reduction

The management of abdominal aortic aneurysm with endovascular repair (EVAR) requires extended exposure to ionizing radiation, before, during and after the intervention. The aim of this study was to quantify the radiological risks to patients and operating team, and to develop strategies to assess and reduce them.

EVAR was carried out in 97 patients using either a low-power mobile or a high-power stationary fluoroscopic unit. Empirically determined relationships between the indicated dose area product (DAP) and peak skin dose, obtained by direct in vivo dosimetry in a subgroup of patients, were used to predict the peak skin dose. Individual worker monitoring was used to assess personnel radiological burden.

The probability for radiation induced biological effects due to the repair itself and the preoperative and life-long surveillance, as carried out, was about 2.4 10-3. The peak skin dose of repairs was linearly correlated with the DAP and did not exceed 1.2 Gy. The collective effective dose of the staff that carried out repairs using the mobile unit was 5.5 and 8 μSv per repair using an angiographic and a surgical table, respectively. The use of the high-power fluoroscopic unit resulted in a many fold higher radiation burden to both patient and personnel.

The optimum strategy, including equipment-related factors, procedure-conduct factors and follow-up procedures, has to be studied, justified and optimized in each medical facility.