Symptoms,Vascular anatomy and endovascular treatment of spinal cord arteriovenous malformations.

SUMMARY: The purpose of this study is to evaluate the symptoms, anatomy and efficacy of embolization of spinal cord AVMs (SCAVMs). We performed retrospective analysis of 108 SCAVMs consisting of 38 pediatric and 70 adult cases. They included 81 nidus (26 pediatric) and 27 fistulous (12 pediatric) AVMs. Hemorrhage occurred in 74% of pediatric and 62% of adult cases with multiple hemorrhages in 54% of pediatric and 42% of adult cases. Fistulous AVMs hemorrhaged more frequently in children than adults (75% vs. 13%). 75 cases were treated with embolization alone, 10 with surgery and embolization , 2 with embolization following radiation and 12 with surgery alone. 9 patients received no treatment. In 79 of 87 embolized patients, acrylic was utilized either alone (49) or in combination (30) with other materials. Embolization was attempted 156 times in 93 patients. Complete obliteration by embolization was obtained in 17 cases. If complete obliteration was not possible, partial targeted embolization was performed, aiming at dangerous anatomic structures such as aneurysms. During the follow-up period (mean: 34 months), hemorrhage was observed in only 2 cases. Although technical complications such as dissection or vasospasm occurred on 19 occasions, only 4 resulted in aggravation of neurological symptoms. Of the 21 sessions in which worsening of symptoms occurred after embolization, 10 resulted in permanent deficits and eight of these occurred prior to 1990. SCAVMs have a poor functional prognosis due to frequent hemorrhage if untreated. Embolization with acrylic is feasible as the first choice of treatment. Provocative test and electrophysiological monitoring have improved safety. Partial targeted embolization is effective in preventing hemorrhage.