Modified Park Bench Position for Superior Vermian Arteriovenous Malformations and Dural Fistulas

Objectives Arteriovenous malformations (AVMs) of the superior cerebellar vermis and dural arteriovenous fistulas (dAVFs) draining into tentorial venous structures are uncommon lesions. Various surgical approaches and positions have been used to gain access. Methods We present our experience with 10 superior vermian AVMs and 3 dAVFs with retrograde transverse sinus or torcular drainage, each resected through a supracerebellar infratentorial approach in the park bench position with modification of the neck and head position (vertex tilt-up instead of down). Results All 13 patients were treated surgically, with 4 receiving adjunctive endovascular embolization. Postoperative digital subtraction angiography confirmed complete resection of lesion in all. One patient experienced superficial wound infection treated by oral antibiotics, and another presented with a cerebrospinal fluid collection due to delayed hydrocephalus requiring insertion of a ventriculoperitoneal shunt. The median modified Rankin Scale score at last follow-up was 1. There were no surgical complications at the time of last follow-up. Conclusions Our series shows that for superior vermian AVMs or dAVFs with retrograde transverse sinus or torcula venous drainage, the supracerebellar infratentorial approach in a modified vertex tilt-up park bench position is a safe and effective surgical approach.