Pre-operative Simulation of the Appropriate C-arm Position Using Computed Tomography Post-processing Software Reduces Radiation and Contrast Medium Exposure During EVAR Procedures

Abstract

The aim was to evaluate the feasibility and efficacy of a new method for pre-operative calculation of an appropriate C-arm position for iliac bifurcation visualisation during endovascular aortic repair (EVAR) procedures by using three dimensional computed tomography angiography (CTA) post-processing software. Post-processing software was used to simulate C-arm angulations in two dimensions (oblique, cranial/caudal) for appropriate visualisation of distal landing zones at the iliac bifurcation during EVAR. Retrospectively, 27 consecutive EVAR patients (25 men, mean±SD age 73±7 years) were identified; one group of patients (NEW; n=12 [23 iliac bifurcations]) was compared after implementation of the new method with a group of patients who received a historic method (OLD; n=15 [23 iliac bifurcations]), treated with EVAR before the method was applied. In the OLD group, a median of 2.0 (interquartile range [IQR] 1-3) digital subtraction angiography runs were needed per iliac bifurcation versus 1.0 (IQR 1-1) runs in the NEW group (p=.007). The median dose area products per iliac bifurcation were 11951mGy*cm2 (IQR 7308-16663mGy*cm2) for the NEW, and 39394mGy*cm2 (IQR 19066-53702mGy*cm2) for the OLD group, respectively (p=.001). The median volume of contrast per iliac bifurcation was 13.0mL (IQR: 13-13mL) in the NEW and 26mL (IQR 13-39mL) in the OLD group (p=.007). Pre-operative simulation of the appropriate C-arm angulation in two dimensions using dedicated computed tomography angiography post-processing software is feasible and significantly reduces radiation and contrast medium exposure.