Microsurgical clipping of previously endovascularly treated intracranial aneurysms: A single centre case series

With increasing numbers of cerebral aneurysms being treated endovascularly, an increasing number of intracranial aneurysm (IA) recurrences/residuums post-endovascular treatment (EVT) are being encountered. This single centre study aims to assess the surgical technique, outcomes and complications of patients undergoing microsurgical clipping of IA following previous EVT.

All patients undergoing microsurgical clipping of IAs post-ETV over the last 3 years were identified and included. Ruptured and unruptured IAs were included. Patient demographics, EVT techniques, surgical technique and time to clipping were examined. The following outcomes were recorded; intra-operative complications, post-operative complications, 30-day and 12-month survival.

In total, 23 cases were included in this study. Median age at microsurgical clipping was 57 years (range: 22 - 75 years). Median time to clipping from primary EVT was 37 months (range: 7 months - 18 years). Three cases (13 %) presented due to subarachnoid haemorrhage (SAH). The most commonly employed primary endovascular technique was simple coiling alone (n = 14, 61 %). Median time from primary treatment to surgery was 35 months (range: 7 months - 18 years). Multiple clips were required in 48 % (n=11). Five (22 %) cases required EVT device removal. Intra-operative complication rate was 4 %, with one case of intra-operative rupture. 30-day survival was 100 %. 12-month survival was 96 %.

Microsurgical clipping of previously endovascularly treated IAs is a challenging but feasible treatment with high obliteration rates. EVT device removal was not required in the majority of cases. Surgical adjuncts such as the endoscope can be particularly useful in optimising clip placement.