Distal posterior inferior cerebellar artery aneurysm with cerebellar arteriovenous malformation treated by open surgery: a case report

BACKGROUND: The detection of a feeder aneurysm and an arteriovenous malformation (AVM) is relatively rare for the intracranial AVM. The distal posterior inferior cerebellar artery aneurysm (DPICAAn) is reported to coexist or relate with the cerebellar AVM. In previous reports about the treatment of a DPICAAn and a cerebellar AVM, endovascular embolization with the sacrifice of the posterior inferior cerebellar artery (PICA) has often been selected. However, there have been few reports of simultaneous open surgery for coexistent cases of DPICAAn and cerebellar AVM. CASE DESCRIPTION: A 67-year-old male presented with a headache. We detected a right DPICAAn in the telovelotonsillar segment and a cerebellar AVM primarily fed by the left superior cerebellar artery (SCA). In addition, the nidus was located medially in the left upper cerebellar hemisphere. Magnetic resonance imaging raised suspicions of asymptomatic past hemorrhage in the cerebellar AVM. The left PICA was agenesis, and the right PICA perfused the bilateral inferior cerebellar hemispheres; thus, the right PICA could not be sacrificed. We selected open surgery to prevent any hemorrhagic event from the DPICAAn and the cerebellar AVM. The cerebellar AVM was completely removed, and the DPICAAn was successfully clipped in a single-session open surgery. CONCLUSIONS: Open surgery can be considered for DPICAAn and cerebellar AVM. The anatomical location of the DPICAAn and AVM contributed to the success of a single-session open surgery.