Spinal arterio-venous malformations simulating multiple sclerosis: importance of early diagnosis

Two cases of spinal arteriovenous malformation (AVM) in young patients are presented. Symptoms were compatible with the spinal form of multiple sclerosis in both cases. The lesions were not diagnosed on initial evaluation. Subsequently they were found by myelography and arteriography, the one eight months and the other nine years after the first symptoms. The contrasting clinical courses of the two patients suggest that: (a) the diagnosis of multiple sclerosis where symptoms and signs are restricted to the spinal cord should be made only after a thorough investigation which includes myelography, to rule out the presence of a surgically correctible lesion such as an AVM; (b) myelography should be carried out in both the supine and prone positions as an AVM may be completely missed by routine prone myelography views; (c) early surgery of the resectable AVM may prevent a progressive deterioration of neurological function, making early diagnosis particularly important.