Proposed New Treatment Approach for Unruptured Cerebral Aneurysms: Based on the Outcome of 240 Consecutive Keyhole Clipping Surgeries

Abstract

Clipping through a keyhole minicraniotomy is a modern option for treating cerebral aneurysms and is less invasive than standard craniotomy. We report the findings of 240 consecutive keyhole clipping surgeries performed in 231 patients aged 34-79 years (mean 63 ± 9 years), resulting in the treatment of 251 unruptured anterior circulating aneurysms. The aneurysms were relatively small (<10 mm). Anterior communicating artery aneurysms (57 cases) and internal carotid artery aneurysms (44 cases) were treated through the supraorbital keyhole (mean size, 29 ± 3 mm) approach (Perneczky method). Middle cerebral artery aneurysms (139 cases) were treated through the pterional keyhole (mean size, 25 ± 2 mm) approach. Each surgery was individualized by using detailed preoperative simulation based on three-dimensional computed tomography angiography.Neck clipping was performed for 244 aneurysms (97%); wrapping was done for 3 aneurysms due to blister or motor-evoked potential abnormality; and neck remnant was identified in 4 aneurysms. Complete stroke occurred in 1 patient and mild dementia in 1 patient. Lacunar infarction developed in 6 patients (2.5%; 2 symptomatic, 4 asymptomatic); however, there were no hemorrhagic complications.Frontalis muscle palsy persisted in 5 patients (2.1%), and chronic subdural hematoma was treated surgically in 13 patients (5.4%). The outcomes at 3 months were score 0 (99.2%), score 1 (0.4%), and score 3 (0.4%) on the modified Rankin scale, and 212 patients (92%) were discharged within 3 days after surgery. The keyhole approach is an effective and minimally invasive treatment option for relatively small unruptured aneurysms.