PCA動脈瘤への手術アプローチの検討

Abstract

To identify safe and appropriate surgical approaches, we analyzed our experience with posterior cerebral artery (PCA) aneurysms (ANs), and reviewed the literature. We encountered 3 patients with PCA ANs. Two had ruptured ANs, and the third case had an unruptured PCA AN associated with a ruptured anterior communicating artery AN. The locations of the 3 PCA ANs were the P1, P2a, and P2p segments, respectively. All patients had saccular ANs and underwent direct surgery. The anterior temporal approach was selected for the P1 and P2a ANs. For the P2p AN, we initially selected a transchoroidal fissure (trans-CF) approach via the left inferior temporal gyrus. With this approach, exposure of the AN was difficult, as it was located well below the anterior choroidal artery. We then switched to a subtemporal approach intraoperatively to expose the AN. Neck clipping was successful for all the PCA ANs, and there were no complications. P1 and P2a ANs are safely accessed by an anterior temporal approach. A subtemporal approach is suitable for a low-positioned P2p AN; however, a high-positioned P2p and the anterior part of a P3 AN are candidates for a trans-CF approach. The choice of an appropriate surgical approach depends on the segment of the PCA; however, these ANs can be safely treated with direct surgery.