Distal Outflow-Related Anterior Inferior Cerebellar Artery Aneurysm in Hemangioblastoma.

Anterior inferior cerebellar artery (AICA) aneurysm is a rare cerebral entity, and its presentation in association with a hypervascularized tumor is even more exceptional. In this study, we describe a patient with rare coexistent pathologic conditions in combination with a cerebellar hypervascularized tumor with an outflow-related AICA aneurysm. A 1-stage procedure to remove both lesions was carried out after meticulous discussion with patient. Postoperative imaging demonstrated no residual aneurysm and total resection of the tumor, which was pathologically diagnosed as hemangioblastoma (HB). She made an excellent neurologic outcome and was discharged in unremarkable condition. At her 3-month follow-up visit, her condition remained stable for vasculopathologic states and neurologic functions. To our knowledge, this is the first published clinical experience regarding cerebellar HB coexistent with an AICA aneurysm that involved the efferent segment of the tumor's feeding vessel. Patients with coexistent vascular pathologic conditions should be aggressively treated, not by the wait-and-see practice, in case of unexpected rupture in the future.