Intentional Severing of the Internal Carotid Artery in the Surgical Treatment

Thrombosed brain aneurysm is usually treated by cerebrovascular surgery rather than endovascular surgery. The basilar-superior cerebellar artery (BA-SCA) aneurysm can be accessed via the transsylvian, temporopolar, or anterior temporal approaches. However, a disadvantage of these approaches is that the surgical route is obstructed by the internal carotid artery (ICA). Therefore, we propose that after establishing a high-flow bypass, severing the ICA will enable safe clipping of a BA-SCA aneurysm.

In this case, we sought to clip a large thrombosed BA-SCA aneurysm; however, the operative field was limited by the ICA after using a zygomatic anterior temporal approach with anterior clinoidectomy, including severing of the distal dural ring. Therefore, after establishment of a high-flow bypass, the operative field was widened by intentional severing of the ICA between the ophthalmic artery and posterior communicating artery. Using this procedure, we achieved complete obliteration of the thrombosed BA-SCA aneurysm without additional arterial ischemic complications.

Intentional severing of the ICA after establishing a high-flow bypass will not become the standard technique for treatment of upper basilar artery aneurysms. However, this technique can extend the operative field to allow clipping of an upper basilar artery aneurysm after several skull base techniques.