03:00 Abstract No. 13 Dose reduction using digital fluoroscopy versus digital subtraction angiography (DSA) in endovascular aneurysm repair (EVAR): single-center prospective randomized comparison

Abstract

EVAR can result in high radiation dose to patients and operators. Optimal imaging is required for safe stent graft deployment. While DSA provides high quality images, radiation dose rate is increased compared to digital fluoroscopy (DF). The aim of this prospective randomized study was to assess if radiation dose in EVAR could be reduced by predominantly utilizing DF for implantation compared to the standard DSA-utilized technique. Between 2011 and 2017 patients meeting inclusion criteria for EVAR of infrarenal abdominal aortic aneurysms were prospectively enrolled. Complex repair (i.e., fenestrated EVAR, parallel stent grafts) and thoracic EVAR cases were excluded. Patients were randomized to either a standard technique in which DSA could be used freely or a DF cohort in which DF was used for implantation but ≤ 2 DSA runs were allowed for confirmatory imaging at conclusion of the case. Body mass index (BMI), technical success, dose area product (DAP), cumulative air kerma (CAK), fluoroscopy time (FT), conversion rate to DSA (when fluoroscopy was inadequate for visualization) and number of DSA runs were recorded. 43 patients met inclusion criteria; 26 were randomized to the DF group and 17 to DSA. Technical success was 43/43 (100%). 5/26 (19%) required conversion to DSA. In an intention-to-treat analysis, DAP was reduced by 24% in the DF cohort (DSA=174 Gycm2, DF=132 Gycm2[p=0.04]), with no significant difference in CAK; median DSA acquisitions respectively were 7 and 1 (range 5-10, 0-9). When accounting for 5 conversions and dividing groups by number of DSA runs such that the DF cohort had ≤2 acquisitions and the DSA cohort had ≥3 acquisitions, DAP was reduced by 41% (DSA=185 Gycm2, DF=110 Gycm2 [p<0.01]), and CAK dose was reduced by 40% (DSA=964 mGy, DF=578 mGy [p<0.01]); median DSA acquisitions respectively were 7 and 1 (range 3-10, 0-2). In 21/26 (81%) of patients, digital fluoroscopy was adequate for safe implantation during EVAR. When the number of DSA runs was ≤2, radiation dose was reduced by 41%. If image quality allows, a fluoroscopy-only or limited DSA approach to EVAR can significantly reduce radiation dose.