Clipping of a giant thrombosed anterior communicating artery aneurysm with A3-A3 bypass: A technical case report with 4K video.

BACKGROUND: Giant thrombosed anterior communicating artery (AComA) aneurysms represent a significant neurosurgical challenge with no consensus regarding their optimal management. It often requires an intraaneurysmal thrombectomy, which necessitates temporary inflow occlusion. This carries a substantial risk of ischemic complications. We report a case of a giant thrombosed AComA aneurysm that was successfully treated with clipping combined with intra-aneurysmal thrombectomy and an A3-A3 bypass. METHODS: A 55-year-old man presented with temporal quadrantanopia of the right eye caused by a giant thrombosed AComA aneurysm compressing the optic nerve. To facilitate safe thrombectomy under temporary A1 occlusion, a side-to-side A3-A3 bypass was constructed in advance to preserve distal anterior cerebral artery (ACA) perfusion and reduce the risk of ischemia. Intra-aneurysmal thrombectomy and definitive clipping were then performed. RESULTS: The aneurysm was successfully obliterated. Postoperatively, the patient showed improved visual function without frontal lobe deterioration or new neurological deficits. CONCLUSION: Prophylactic A3-A3 bypass provides critical distal ACA protection during the surgical management of giant thrombosed AComA aneurysms. This strategy may enhance surgical safety and reduce ischemic complications. A video of the surgical operation is presented, and the safety and reliability of the surgical procedure are discussed.