Risk of radiation exposure during endovascular aortic repair

Abstract

Objective: Exposure to radiation doses above 2 Gray (Gy) can cause skin burns. There is also a lifetime cancer risk of ≈5.5% for every Sievert (Sv) of radiation. We assessed the radiation burden associated with endovascular treatment of the aorta.

Method: Thoracic (TEVAR), Infra-renal (IEVAR) and branched/fenestrated (BEVAR/FEVAR) endovascular aortic repairs were studied. The prospectively recorded dosimetric parameters included: fluoroscopy time and dose area product (DAP). Exposure films, placed underneath 10 patients intra-operatively, recorded skin dose and were used to calculate skin (Gy) and tissue (Sv) doses.

Results: The TEVAR cohort (n = 232) were younger (p < 0.0001) than BEVAR/FEVAR (n = 53) and IEVAR (n = 630). The median DAP was higher (p = 0.004) in the BEVAR/FEVAR group compared with IEVAR and TEVAR: 32,060 cGy cm(2) (17,207-213,322) vs 17,300 cGy cm(2) (10,940-33,4340) vs 19,440 cGy cm2 (11,284-35,101), respectively. The equivalent skin doses were BEVAR/FEVAR: 1.3 Gy (0.71-8.75); IEVR: 0.71 Gy (0.44-13.7); TEVAR: 0.8 Gy (0.46-1.44). The whole body effective doses were BEVAR/FEVAR: 0.096 Sv (0.052-0.64); IEVR: 0.053 Sv (0.033-1.00); TEVAR: 0.058 Sv (0.034-0.11).

Conclusions: The radiation exposure during endovascular aortic surgery is relatively low for the majority but some patients are exposed to very high doses. Efforts to minimise intra-operative exposure and graft surveillance methods that do not use radiation may reduce the cumulative lifetime malignancy risk.