Spinal Arteriovenous Malformation

A 16 year-old female presented with recurrent bleeds into a spinal lesion. Sagittal T2-weighted spin-echo imaging demonstrates a complex arteriovenous malformation involving the upper cervical cord. Adjacent bone and soft tissue are also involved.
Arteriovenous malformations of the spine are classified into: type I (dural AV fistula); type II (intramedullary glomus-type AVM); type III (juvenile-type intra+extramedullary AVM); and type IV (direct extramedullary AV fistula). The type shown above is type III. Type III AVM often have extramedullary and extraspinal involvement, and are typically fed by multiple vessels. Type III are more common in the cervical and thoracic spine. Type III lesions are considered congenital and typically present before age 30.
Reference: Brant-Zawadzki M, et al. Pocket Radiologist: Spine, Top 100 Diagnoses. Amirsys 2002
Credit: Dr Laughlin Dawes
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