SPINAL ARTERIOVENOUS-MALFORMATIONS - CLINICAL AND NEUROPHYSIOLOGICAL FINDINGS

Eighteen patients with dural arteriovenous fistulas or intradural arte riovenous malformations underwent clinical and neurophysiological exam ination. Bladder disturbances, pain, sensory abnormalities and involve ment of both upper and lower motor neurons were commonly observed. Abn ormal findings were obtained both in electromyography (11/18) and soma tosensory evoked potentials (16/18). The motor evoked potentials were abnormal in all but one patient and showed a prolonged central (n = 14 ) or peripheral motor conduction time (n = 6). In three cases both val ues were prolonged. The results of nerve conduction studies in the pat ients with prolonged peripheral motor conduction times were normal. Th ese neurophysiological findings may indicate root involvement in some patients, probably due to venous congestion and consequent hypoxia, as there were no signs of root compression on neuroradiological evaluati on in any of these six patients. Motor evoked potentials may provide a n additional clue to the diagnosis, although patients with spinal sten osis or motor neuron disease may present with similar findings.