Surgical interventions in intracranial arteriovenous malformations: Indications and outcome analysis in a changing scenario

Background : Intracranial arteriovenous malformations (AVM) are being increasingly managed by multimodality approach. This changing scenario encouraged us to study the present state of surgery in intracranial AVMs and the outcomes.
Materials and Methods : Of a total of 868 patients evaluated for suspected or known AVMs between January 2000 and July 2008, 790 had intracranial AVMs. The clinical characteristics and surgical outcomes of the 111 opeated patients were analyzed.
Results : Of the 111 patients, 73 were males. Clinical features included: Headache (70%), loss of consciousness (48%) and seizures (32%). The commonest AVM grade was Spetzler-Martin (SM) grade II (41%), 7% had AVM> 6 cm and 78% had evidence of bleed. In total 143 surgeries were performed and 22% of patients required multiple interventions. The types of surgical interventions included elective excision of AVM in 23%, emergency surgery (either AVM excision or evacuation of hematoma) in 55%, surgery following radiosurgery/embolization in 5% and palliative non-definitive surgeries (e.g. shunt) in 15%. Post-operative angiography was done in 67% of patients. Obliteration rates for elective excision of AVM in Spetzler Martin Grade I, II, IIIa, IIIb and IV were 100%, 71%, 33%, 50% and 67% respectively (mean follow-up:31.6 months). Of 39 patients with residual AVMs, 33 received gamma knife and four underwent embolization. Outcome was modified Rankin scale (mRS) grade 1 in 34% of paitnets and the overall favorable outcome was 83% and there were six deaths.
Conclusion : In our patients′ cohort one in every eight patients required surgery. In intracranial AVMs, surgery still plays an important role. In developing countries like India it may be beneficial to electively excise Grade I and II AVMs if cost is a consideration.

Keywords
Intracranial arteriovenous malformations, surgery, surgical intervention, surgical outcome