title: Factors that affect the surgical outcomes of spinal dural arteriovenous fistulas.
abstract: BACKGROUND
  Authors disclose the factors that affect the surgical outcome of the spinal dural AVFs from the retrospective analysis of 13 cases.
  
  
  METHODS
  Thirteen patients with spinal dural AVF underwent microsurgical treatments between 1990 and 2004 at the Department of Neurosurgery, Aso Iizuka Hospital. The mean age was 62 years, and the median time to diagnosis was 38 months (range, 4-120 months). There were 12 men and 1 woman. The clinical features were characterized by spastic paraparesis in all 13 patients and micturition problem in 11 patients. All 13 patients showed the longitudinal extension of the high T2 intramedullary signals in magnetic resonance (MR) image. The microsurgical obliterations of the spinal dural AVFs were performed for all 13 patients because the endovascular treatments were difficult or failed to obliterate the lesions.
  
  
  RESULTS
  The durations of the symptoms were not directly correlated to the preoperative neurological conditions and the postoperative outcomes. The patient's age and the preoperative severity of myelopathy affected the postoperative outcomes. The mode of the longitudinal extension of the high T2 intramedullary signals in MR image, rostral or caudal, did not show the statistical significance to the outcome. The poor outcomes were observed in elderly patients and patients with preoperative modified Rankin Scale 4 and 5. A case with multiple spinal dural AVFs is also presented.
  
  
  CONCLUSIONS
  The spinal AVFs are treatable lesions through microsurgery or embolization. The likelihood of favorable outcome was affected by the severity of deficits and the patient's age.
authors.affiliation: Department of Neurosurgery, Kyushu University Graduate School of Medical Sciences, Fukuoka City 812-8582, Japan. snagata@ns.med.kyushu-u.ac.jp
authors.forename: Shinji
authors.initials: S
authors.lastname: Nagata
authors.forename: Takato
authors.initials: T
authors.lastname: Morioka
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Natori
authors.forename: Koichiro
authors.initials: K
authors.lastname: Matsukado
authors.forename: Tomio
authors.initials: T
authors.lastname: Sasaki
authors.forename: Tomomi
authors.initials: T
authors.lastname: Yamada
mesh_terms: D000368:Aged; D000792:Angiography; D020785:Central Nervous System Vascular Malformations / Q000473:pathology / Q000601:surgery*; D005163:Factor Analysis, Statistical; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008866:Microsurgery / Q000379:methods*; D008875:Middle Aged; D019635:Neurosurgical Procedures / Q000379:methods*; D011184:Postoperative Period; D011300:Preoperative Care; D012189:Retrospective Studies; D012720:Severity of Illness Index; D013116:Spinal Cord / Q000098:blood supply* / Q000601:surgery*; D016896:Treatment Outcome