Intra-cranial aneurysm treatment with contour or WEB – a single center comparison of intervention times and learning curves

Treating aneurysms with intra-saccular flow disruption is a feasible alternative to coil-embolization. Besides the established WEB device, the novel Contour Neurovascular System has emerged as a potentially easier alternative regarding sizing and deployment. We report the learning curve experienced at our center from the first 48 patients treated with Contour and compared it with 48 consecutive WEB cases.Both groups were compared concerning intervention time, sizing failures leading to device changes and radiation dose. Additionally, we analyzed potential learning effects by comparing the first 24 Contour cases with our last 24 Contour cases and WEB cases respectively.Patient demographics, acute vs. incidental cases and aneurysm localization were comparable in both groups. The deployment time was faster in our 48 Contour cases (median: 22.0 ± 17.0 min), than in the WEB group (median: 27.5 ± 24.0 min). Total intervention time was similar for Contour (median: 68.0 ± 46.9 min) and WEB cases (median: 69.0 ± 38.0 min). Device implantation times in our WEB cases were slightly shorter in the later cases (median: 25.5 ± 24.1 min) than in the earlier (median: 28.0 ± 24.4 min) cases. In the Contour cohort, deployment times were similar for the first 24 cases (median: 22.0 ± 14.5 min) and the final 24 (median: 22.0 ± 19.4 min). Radiation dose was lower in the Contour group (1469.0 ± 1718 mGy*cm2 vs. 1788.0 ± 1506 mGy*cm2 using the WEB device). Less intra-procedural device changes were performed in the Contour cohort (6 of 48 cases, 12.5%), than in the WEB group (8 of 48 cases, 16.7%).Aneurysm occlusion times and consequently radiation doses, as well as the amount of device changes were lower in the Contour group. Occlusion times did not differ in the first and last 24 Contour cases, leading to the assumption that the handling of Contour does not require extended training. A short training effect in occlusion times was noted, however, between the first and last WEB cases as shorter procedure times were seen in the latter cases.