Treatment of medullary aneurysm in the collateral circulation with a flow diverter: A case report.

ABSTRACT

INTRODUCTION AND IMPORTANCE Spinal aneurysms rarely occur in the collateral circulation of the vertebral artery (VA). These aneurysms are difficult to treat. A flow diverter (FD) can be a therapeutic option. CASE PRESENTATION A 62-year-old man suffered subarachnoid hemorrhage. His Hunt-Hess scale classification was grade II. Digital subtraction angiography (DSA) revealed that the bilateral distal VAs were occluded, there were two flow-related aneurysms in the collateral circulation of the first radicular artery of the VA, and there was a dissecting aneurysm at the origin of the posterior inferior cerebellar artery (PICA). The FD covered the PICA dissecting aneurysm, and the first radicular artery originated in the VA. Postoperatively, computed tomography angiography revealed a patent PICA and regression of the aneurysm in the collateral circulation. At the one-month follow-up, he showed good recovery and was therefore allowed to return to work. Follow-up DSA confirmed the regression of the aneurysms. However, the intracranial VA and PICA were unexpectedly occluded. CLINICAL DISCUSSION: It is difficult to catheterize aneurysms in the collateral circulation to perform coiling. It is also dangerous to embolize such aneurysms with a liquid embolic agent. After FD deployment to cover the origin of the parent artery, the hemodynamic stress of the aneurysm decreases, and the aneurysm can regress. CONCLUSION: Aneurysms in the collateral circulation were not accessible. FD deployment in the parent artery to cover the origin of the feeding artery of the collateral circulation is feasible for treating such aneurysms.