Spinal Vascular Malformations

Spinal vascular malformations are rare vascular lesions affecting the spine, spinal cord, and sometimes the surrounding tissues. Various classification systems have been proposed. Dural arteriovenous fistulae are the most common spinal vascular malformations. These lesions are the result of a direct shunt between a radiculomeningeal artery and a radicular vein and typically present with progressive symptoms. They are often successfully treated with occlusion of the shunting zone and proximal draining vein via an endovascular or surgical approach. Arteriovenous malformations are composed of an aberrant nidus of arteries and veins without an intervening capillary bed and are subdivided into intramedullary, extradural-intradural, and conus medullaris subtypes. Treatment may be surgical, endovascular, or a combination of the two approaches. Pial arteriovenous fistulae are typically ventral fistulae deriving their supply from pial arteries, most commonly from the ASA. These are subdivided into types A-C. Surgical treatment is often advocated for types A and B, while endovascular embolization is often used for type C lesions. Spinal cavernous malformations are well-circumscribed lesions composed of tightly packed thin-walled vessels without intervening parenchyma. Management of incidental or minimally symptomatic lesions can be controversial, but published data seems to support the safety of conservative management for incidental lesions. Surgical treatment is the mainstay of therapy for spinal cavernous malformations causing acute, deteriorating symptoms or progressive myelopathy. Spinal aneurysms are extremely rare lesions that may present with compressive symptoms but more commonly present with acute pain due to hematorrhachis. Treatments for these lesions reported in the literature are often surgical.