Surgical Management of Spinal Cord AVMs

Surgical management of spinal vascular lesions is challenging owing to the location of the lesion (i.e., intramedullary), blood supply (intrinsic spinal cord vessels, direct aortic tributaries), preoperative diagnostic accuracy, and intraoperative identification of the lesion. The clinical presentation of spinal cord AVMs is characterized by myelopathy due to different pathological mechanisms. Reduced blood supply, increased venous pressure, and hemorrhage have all been described as culprits for neurological manifestations. Second-hit events, such as hemorrhage, are as high as 10% per year with detrimental consequences, so early and definitive treatment of these lesions is paramount for optimal clinical outcomes. Unlike brain AVMs, partial treatment of spinal cord lesions is safe and allows preservation of spinal feeding arteries while reducing the risk of rebleeding and improving long-term outcomes. Surgical resection of spinal AVMs depends on favorable angioarchitecture, allowing a safe resection without risking the spinal cord blood supply. Several classifications have been proposed to aid in the diagnostic and therapeutic management of these lesions. Most recently, the Toronto classification has been proposed with guidance on treatment modality and occlusion success rate. This chapter describes spinal cord vascular lesions’ diagnostic course and surgical management.