The Microsurgical Management of a Cerebellar Vermian Arteriovenous Malformations Associated With High-Flow Fistulae: 2-Dimensional Operative Video

Abstract

Arteriovenous malformations (AVM) in the posterior fossa represent 2% to 15% of all brain AVMs, are often smaller, and have a higher risk of hemorrhage. [1][2][3][4] The presence of a single draining vein, venous stenosis, and high-flow fistulae increases hemorrhage risk but also venous congestion. [3][4][5][6] AVM associated with high-flow fistula can be managed surgically, radiosurgically, or endovascularly. 7-10 Embolization of the associated fistula is reported to be safer than embolization of the nidus. 7 Surgery is favored in the symptomatic patient when concerns over the latency from radiosurgery to obliteration and overshooting the shunting zone during embolization predominate. 4,11 For small AVM with high-flow shunts localization of the nidus and fistulous connection is the main challenge. Sinus skeletonization in complex dural arteriovenous fistula is a reported technique. 12 We adapt this technique to delineate and disconnect a subpial posterior fossa AVM with high-flow fistula. We present a video case of an obese male in his 50s with hypertension and end-stage renal disease who presented with a 9-month history of progressive spastic quadriparesis. The patient consented to the procedure. Examination revealed grade 2 power on the left and grade 4 on the right with brisk reflexes. MRI showed T2 signal hyperintensity in the pons, and digital subtraction angiography confirmed an AVM overlying the culmen of the vermis with feeders from the S3 segment of the superior cerebellar artery, draining into the precentral vein. We demonstrated that surgical management of micro-AVMs with associated high-flow fistulae can be safely achieved in experienced hands using technique of vein skeletonization guided by indocyanine green angiography. The patient signed the Institutional Consent Form, which states that he accepts the procedure and allows the use his images and videos for any type of medical publications in conferences and/or scientific articles.