Two Indices Affecting the Directions of the Sylvian Fissure Dissection in Middle Cerebral Artery Bifurcation Aneurysms
A 65-year-old woman presented with severe headache due to a ruptured right MCA bifurcation aneurysm. It was easy to expose the M1 vessel for proximal control through distal to proximal sylvian fissure dissection so she is assigned to group II. The M1 slope gap was 6.53 mm and the M1 angles was 51.7° (). We confirmed this in the intraoperative surgical view ().