P2 aneurysm approached via the temporal horn: technical case report.

Objective And Importance: We report the use of a transcortical transventricular approach to a P2 aneurysm, which was located near the choroidal fissure, protruded into the temporal horn, and was considered to be too difficult to approach by the conventional subtemporal route.

Clinical Presentation: An 81-year-old woman suddenly developed severe headache with vomiting and subsequently lost consciousness. Computed tomographic scans revealed a diffuse intraventricular hemorrhage and subarachnoid hemorrhage. Cerebral angiography disclosed a saccular aneurysm in the right P2 segment.

Intervention: On the 16th day after admission, successful neck clipping was easily performed through the temporal horn via the inferior temporal gyrus. The postoperative course was uneventful.

Conclusion: This special approach may be preferable in such cases, because it protects the brain from the detrimental effects of strong temporal retraction and provides a wider working space.