Surgical Resection of a Complex Spetzler-Martin Grade IV Medial Sylvian Arteriovenous Malformation: 3-Dimensional...

Sylvian arteriovenous malformations (AVMs) are challenging lesions for surgical management. They are classified according to the Sugita classification based on the location of the nidus in the sylvian fissure: pure, lateral, medial, and deep. Resection of these lesions are fraught with risks, as it requires extensive arachnoid dissection in the sylvian fissure in close proximity to surrounding eloquent tissue, and the presence of en passage arteries can resemble feeding arteries. In this video illustration, the authors describe a complex, Spetzler-Martin Grade IV right sylvian AVM and its surgical resection. By Sugita classification, this was a medial sylvian AVM, with an associated flow related middle cerebral artery (MCA) bifurcation aneurysm. Informed consent was obtained from the patient prior to the procedures. The AVM was embolized preoperatively, and surgical resection was carried out via a pterional approach. The detail of the AVM resection is described in the video clip. Postoperative digital subtraction angiography showed complete excision of the lesion, and the patient was discharged to home on postoperative day 6 without any neurological deficit. In 1-yr follow-up angiogram, beside complete obliteration of the AVM, the flow-related MCA bifurcation aneurysm as well as the M1 and M2 vessels have decreased in size and are much less prominent in comparison to the pretreatment angiography.