Inter-observer Variability in Sizing Fenestrated and/or Branched Aortic Stent-grafts

Abstract

Several studies have examined inter-observer variability in measurements for standard EVAR, but little is known about measurements for complex aortic aneurysm. Two independent observers reviewed all preoperative CT scans of 268 patients in a French trial of fenestrated and/or branched aortic stent-grafts (f/b-EVAR). Those data were compared with those obtained (1) by investigators (extent of aneurysm, target vessel stenosis, and aortic diameters), and (2) from manufacturers (proximal landing zone, device diameter, and target vessel position). We assessed the reproducibility using kappa statistics for qualitative data and both Bland-Altman plot and Passing-Bablok regression analysis for quantitative data. Reproducibility was moderate to almost perfect for all factors. However, a few critical discrepancies were found, such as target vessel clock position (≥45 minutes) and location (≥5 mm), level of proximal landing zone, and diameters of the endograft. This is the first large-scale analysis focused on inter-observer variability in sizing for f/b-EVAR. The measurement data showed good agreement, but there were some critical discrepancies between observers that may affect clinical results.