Management of Residual and Recurrent Arteriovenous Malformations

Incompletely obliterated arteriovenous malformations are encountered in clinical practice due to either failure of the primary treatment strategy, latency in treatment effect for radiosurgery, or lesion recurrence. Partial treatment in most circumstances does not confer a protective benefit and generally increases the rate of hemorrhage over the natural history. These lesions must be evaluated based on grade, angioarchitecture, location, previous treatments, and any existing neurological deficits at presentation. For those lesions that are amenable, surgical resection should be undertaken. Lesions that are deemed unsuitable for surgery should be evaluated for radiosurgery. Embolization is generally only useful as part of a multimodal treatment strategy, but may be beneficial in isolation for those patients with associated aneurysms, vascular steal, or the minority in whom a cure can be obtained. Patients must be counseled regarding the natural history, as well as the risks and benefits of any proposed treatment. High-grade (Spetzler-Martin IV and V) lesions are generally best managed conservatively.