Frequency and risk factors for postoperative aneurysm residual after microsurgical clipping

Abstract

Objective Aneurysm residuals after clipping are a well-known problem, but the course of aneurysm remnants in follow-up is not well studied. No standards or follow-up guidelines exist for treatment of aneurysm remnants. The aim of this study was to evaluate the risk factors for postoperative aneurysm remnants and their changes during follow-up. Methods We performed a retrospective analysis of 666 aneurysms treated via clipping in our hospital from 2006 to 2016. Postoperative and follow-up angiographic data were analyzed for aneurysm remnants and regrowth. Clinical parameters and aneurysm-specific characteristics were correlated with radiological results. Results The frequency of aneurysm residuals was 12% (78/666). Aneurysms located in the middle cerebral artery (p = 0.02) showed a significantly lower risk for incomplete aneurysm occlusion. Larger aneurysms with a diameter of 11–25 mm (p = 0.005) showed a significantly higher risk for incomplete aneurysm occlusion. Five patients underwent re-clipping during the same hospital stay. Remnants were stratified based on morphological characteristics into “dog ears” (n = 60) and “broad based” (n = 13). The majority of the “dog ears” stayed stable, decreased in size, or vanished during follow-up. Broad-based remnants showed a higher risk of regrowth. Conclusions A middle cerebral artery location seems to lower the risk for the incomplete clip occlusion of an aneurysm. Greater aneurysm size (11–25 mm) is associated with a postoperative aneurysm remnant. The majority of “dog-ear” remnants appear to remain stable during follow-up. In these cases, unnecessarily frequent angiographic checks could be avoided. By contrast, broad-based residuals show a higher risk of regrowth that requires close imaging controls if retreatment cannot be performed immediately.

Navigating Complexity: A Comprehensive Approach to Middle Cerebral Artery Aneurysms

“…Among them, fusiform shape was the one that mainly drew us towards choosing bypass as a rescue strategy in cases of unfeasible clipping reconstruction. Indeed if distal flow could not be preserved with the clipping strategy, trapping and bypass were required [ 17 , 32 , 33 ].…”

Insufficient Closing Forces of Yasargil Titanium Clips in Two Small Aneurysms Detected with Intraoperative Indocyanine Green Videoangiography

“…12 Clip ligation is associated with high efficacy and low recurrence rates ranging between 0.26 and 0.53%. 13 Known risk factors for aneurysmal remnants or incomplete clipping are larger aneurysms (11–25 mm), 14 aneurysms other than MCA aneurysms, 14 and atherosclerotic walls of the neck. 15…”

“…12 Clip ligation is associated with high efficacy and low recurrence rates ranging between 0.26 and 0.53%. 13 Known risk factors for aneurysmal remnants or incomplete clipping are larger aneurysms (11-25 mm), 14 aneurysms other than MCA aneurysms, 14 and atherosclerotic walls of the neck. 15 A long-term study of 758 aneurysms showed a regrowth risk of 1.83% per year in the case of aneurysmal remnants after incomplete clip ligation.…”

Partial Clipping Occlusion Including Rupture Point Is an Effective Strategy for Ruptured Giant Fusiform Basilar Artery Aneurysm: A Technical Case Report

“…Achieving complete occlusion in brain aneurysm clipping is crucial from the perspective of rupture and recurrence prevention. Obermueller et al ( 20 ) reported post clipping broad-based remnants are at a higher risk of regrowth. And postoperative regrowth is at a higher risk of rupture of the aneurysm ( 21 ).…”