The Bicêtre occlusion scale is well suited to assess the efficacy of the Contour embolization device

The Contour Embolization Device (CED) is typically assessed using coiling angiographic outcomes. However, these scales do not address device-specific problematics. We evaluated the usability of the Bicêtre occlusion scale (BOS) with the CED. BOS scores can be analyzed as BOSS 0 = no residual flow, BOSS 1 = residual flow inside the CED but with complete neck-sealing, BOSS 2 = neck-remnant, BOSS 3 = aneurysm-remnant, BOSS 1 + 3 = contrast filling inside the device and aneurysmal sac without complete neck-sealing. BOS usage should be encouraged as it provides a more comprehensive assessment of the mechanism of CED occlusion, especially considering the potential prognostic value of the neck sealing assessment.