Grade III Arteriovenous Malformations: Postoperative Clinical Outcome

Background: Arteriovenous malformations (AVMs) are complex intra-axial vascular lesions consisting of tangles of abnormal arteriovenous connections without intervening capillary beds. Grade III lesions are heterogeneous group and require the most care in selecting microsurgery or radiosurgery as the treatment option. Objective: In this study, we retrospectively analyzed the post operative clinical outcome of thirteen patients operated upon for intracranial Grade III arteriovenous malformations. Patients and Methods: Thirteen patients with Grade III AVMs were operated, followed up clinically for 6 months and radiologically for one month. after microsurgical excision of the arteriovenous malformations. Results: There were eight patients with Grade III- AVMs (S1V1E1), two patients with Grade III + AVMs (S2V0E1) and three patients with Grade III AVMs (S2V1E0). Eight patients presented with hemorrhage while seizure was the presentation in five patients. Ten AVMs were located in eloquent area and eleven AVMs had central drainage. The clinical outcome at six months interval postoperatively was excellent modified rankin scale (mRS 0-1)in 69.2% and good (mRS 2-3) in 30.8% . No mortality was encountered in our study. The obliteration rate was 92.3%. The clinical outcome was better in (Grade III –) than (Grade III+ and Grade III ). Conclusion: Surgical resection of Grade III intracranial arteriovenous malformations requires careful preoperative evaluation, meticulous surgical technique and proper postoperative care to avoid complications such as rebleeding or stroke.