title: Venous congestion is a major cause of neurological deterioration in spinal arteriovenous malformations.
abstract: OBJECTIVE
  Although venous congestion is considered to be a major cause of progressive myelopathy in patients with spinal dural arteriovenous fistulae (DAVFs), the neurological deterioration in patients with spinal intradural arteriovenous malformations (AVMs) has been attributed to hemorrhage or to vascular steal. To reexamine this theory, we analyzed our own cases of spinal vascular diseases.
  
  
  METHODS
  In 24 patients with spinal vascular diseases, those who demonstrated progressive myelopathy with T2 hyperintensity in the spinal cord on magnetic resonance imaging (MRI) were diagnosed as patients with congestive myelopathy. We further examined the clinical courses, MRI findings, and reversibility of these cases.
  
  
  RESULTS
  Venous congestion was judged to be a cause of neurological deterioration in 13 patients (7 DAVFs, 6 intradural AVMs). The T2 signals on these patients' MRI scans were located in the center and extended over several levels not corresponding to distribution of ischemia due to arterial steal. Of the patients who were diagnosed with congestive myelopathy, no differences between those with DAVFs and those with intradural AVMs were apparent in terms of clinical manifestations and reversibility. Eight (four DAVFs, four intradural AVMs) of 13 patients experienced neurological improvement after treatment. All patients with poor outcomes had intervals from onset of more than 3 years and showed contrast enhancement of the spinal cord on MRI studies.
  
  
  CONCLUSIONS
  Spinal intradural AVMs as well as spinal DAVFs can be a cause of venous congestive myelopathy. Regardless of its etiology, congestive myelopathy is potentially reversible if properly diagnosed and treated.
authors.affiliation: Department of Neurosurgery, Graduate School of Medicine, Kyoto University, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Kataoka
authors.forename: S
authors.initials: S
authors.lastname: Miyamoto
authors.forename: I
authors.initials: I
authors.lastname: Nagata
authors.forename: T
authors.initials: T
authors.lastname: Ueba
authors.forename: N
authors.initials: N
authors.lastname: Hashimoto
mesh_terms: D000328:Adult; D000368:Aged; D001164:Arteriovenous Fistula / Q000150:complications / Q000503:physiopathology; D001165:Arteriovenous Malformations / Q000150:complications* / Q000175:diagnosis / Q000503:physiopathology*; D004388:Dura Mater / Q000098:blood supply; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D012039:Regional Blood Flow; D013116:Spinal Cord / Q000098:blood supply*; D013118:Spinal Cord Diseases / Q000175:diagnosis / Q000209:etiology*; D014680:Veins / Q000002:abnormalities / Q000503:physiopathology*