Microsurgical Clipping of Unruptured Anterior Communicating Artery Aneurysm—A Single-Center Experience

Background/Objectives: Unruptured aneurysms of the anterior communicating artery (AComA) are associated with a higher risk of rupture and present unique anatomical challenges. Although endovascular techniques have advanced considerably, microsurgical clipping continues to represent an essential treatment option, particularly for complex cases. We conducted a retrospective analysis to evaluate outcomes of microsurgical clipping for unruptured AComA aneurysms over an 18-year period at a high-volume tertiary neurosurgical center. Methods: A retrospective analysis was conducted on 106 patients who underwent microsurgical clipping for unruptured AComA aneurysms between 2002 and 2020. Preoperative, intraoperative, and postoperative parameters were assessed. Excluded were previously ruptured or previously surgically treated aneurysms. Logistic regression models were used to identify predictors of postoperative complications with a focus on aneurysm projection. Results: Complete angiographic occlusion was achieved in 92.2% of cases, with a retreatment rate of 0.9%, which is comparable to the recent literature. Permanent neurological deficits occurred in 5.7% of patients. Posterior aneurysm projection was significantly associated with postoperative infarction and permanent neurological deficits. Intraoperative ICG angiography was associated with a reduced risk of ischemic complications. Conclusions: Microsurgical clipping remains a safe and effective treatment for unruptured AComA aneurysms in selected patients, offering durable occlusion and low complication rates. Aneurysm projection is a key predictor of outcome, and intraoperative ICG angiography significantly enhances surgical safety. These findings support the continued role of microsurgery in the interdisciplinary management of AComA aneurysms.