Surgery for a medullary arteriovenous malformation

An arteriovenous malformation (AVM) is a vascular lesion causing an artery to communicate pathologically with a vein, therefore creating an arteriovenous (AV) shunt: - either through an abnormal vascular network interposed between artery and vein and called "nidus », - or directly at full canal: arteriovenous« fistula ». Medullary AVMs can be found at all levels: cervical, thoracic, lumbar or sacral. Peri- or intramedullary arteriovenous malformations can cause spinal compression, ischemia, parenchymal hemorrhage, subarachnoid hemorrhage, or a combination of these lesions. Surgery is indicated if bone marrow function is at risk, but expertise in specialized microsurgical techniques is required. Stereotaxic radiosurgery is useful if the arteriovenous malformation is small and localized in a surgically inaccessible area. Perangiographic embolization occludes the nourishing arteries and often precedes surgical excision or stereotaxic radio surgery.