Intracranial⁃intracranial bypass for the treatment of complex intracranial aneurysms: 9 cases report

Objective To explore the efficacy and advantages of intracranial-intracranial bypass for the treatment of complex intracranial aneurysms. Methods A total of 9 patients with complex intracranial aneurysms who underwent intracranial-intracranial bypass in Xiangya Hospital of Central South University from February 2014 to May 2020 were included, and were treated with grafts bypass or reimplantation of recipient arteries. All cases underwent CTA or DSA to detect the patent of grafts, whether aneurysms were completely clipped or resected and aneurysms recurrence occurred during the follow-up. Modified Rankin Scale (mRS) was used to evaluate the neurological prognosis at discharge and during the follow - up. Results Radial artery (RA) or great saphenous vein (GSV) was used for interposition in 4 cases, and recipient arteries were used for reimplantation in 5 cases. Of 4 cases of interposition, the cavernous sinus seoment of internal carotid artery (ICA)-GSV-ICA bypass was adopted in one case, middle cerebral artery (MCA) M2-RA-M2 bypass in one case, anterior cerebral artery (ACA) A3-GSV-A3 bypass in one case, posterior cerebral artery (PCA) P2 -RA -P2 bypass in one case. Of 5 cases of reimplantation, MCA M2 inferior trunk was reimplanted to M2 superior trunk in one case, ACA A3 was reimplanted to contralateral A3 in 2 cases, the posterior inferior cerebellar artery (PICA) was reimplanted to the anterior inferior cerebellar artery (AICA) in 2 cases. CTA in 3 d postoperatively showed all cases grafts were patent and aneurysms disappeared. After 3 months of discharge, 2 were lost to follow-up. The other 7 cases kept the patency of grafts and no new aneurysms, and were constantly followed up, with an average follow-up time of 30.71 months, and mRS score was 1 or lower. Conclusions Intracranial - intracranial bypass can be applied for complex intracranial aneurysms that are difficult for conventional surgical treatment to solve. Compared with extracranial - intracranial bypass, its grafts are shorter and its hemodynamics features are more in line with physiological conditions.