Internal Carotid Artery Posterior Communicating Artery Aneurysm Accompanied by Oculomotor Palsy: Histopathological Findings

Abstract

There have been few reports about the pathologic features of an intracranial aneurysm accompanied by oculomotor nerve palsy (OMNP). We report the histopathologic features of an internal carotid artery posterior communicating artery aneurysm (Pcom An) with OMNP. A 77-year-old female patient with an acute-onset OMNP received aneurysm neck clipping and additional decompression of the oculomotor nerve through aneurysm sac resection. The histopathological findings demonstrated a pseudo-aneurysm with acute thrombus, elastic lamina disruption, elimination of vascular smooth muscle, and adventitial thinning. The choice between clipping and coiling as a treatment modality is still debated in cases of Pcom An accompanied by OMNP. Coil embolization for psuedoaneurysms may not be curative. In addition, surgery has the advantages of immediate decompression of the oculomotor nerve and the acquisition of unusual aneurysm specimens for pathophysiological investigation. Therefore, clipping may be a suitable treatment for OMNP caused by Pcom An.