1226. Successful treatment of Spetzler-Martin grade 3 arteriovenous malformation (AVM) with Onyx embolisation post Stereotactic radiosurgery

Authors: Neethu Gopal; George Vilanilam; Mohamed S Muneer; Benjamin L Brown; Mohammed Badi (jacksonville, FL)

Introduction: Cerebral arteriovenous malformations (AVMs) are mostly asymptomatic but especially in young adults they can present as acute hemorrhagic stroke, recurrent headaches or seizures. Grade 3 Spetzler-Martin brain AVMs in particular are highly variable in terms of their site of occurrence and angioarchitecture. Previous studies have reported the failure of obliteration of AVMs with Onyx embolization prior to stereotactic radiosurgery (SRS) Here our objective is to define the benefits of Onyx embolization done post stereotactic radiosurgery (SRS) resulting in successful obliteration of AVM. Methods: Case Report Results: A 19-year-old female with a history of Spetzler-Martin grade 3 arteriovenous malformation (AVM) presented with a history of intermittent bifrontal headaches, transient bilateral visual loss, and occasional pulsatile tinnitus, for over two years. Examination revealed moderate bilateral papilledema indicating increased intracranial pressure. Subsequent MR imaging and MR angiogram showed a right posterior temporal arteriovenous malformation measuring approximately 4 cm with surrounding superficial veins. She was started on acetazolamide, which improved her headaches and vision. She was treated withstereotactic radiosurgery for her AVM without pre-operative embolization. Post-procedure she continued to have papilledema and bifrontal headaches and the pulsatile tinnitus improved. In an attempt to decrease arterial flow and venous pressure, she was treated with Onyx embolization of the AVM. Post-embolization MR imaging showed interval decrease in draining vein and AVM nidus. Resultant vasogenic edema surrounding the thrombosed AVM was treated with tapering steroids and hyperbaric oxygen. Two months after embolization, her clinical symptoms have improved and interval MR imaging showed decreased AVM size. Conclusion: Our case demonstrates that AVM can be treated with stereotactic radiosurgery first and subsequent Onyx embolization, for managing AVM and decreasing venous hypertension respectively.