title: Diffuse white matter damage is absent in neuromyelitis optica.
abstract: OBJECTIVE
  Neuromyelitis optica (NMO) is an idiopathic mostly relapsing inflammatory disease with attacks on the optic nerves and spinal cord. Whether NMO is a separate disease or a subtype of classic multiple sclerosis (MS) is unclear. Clinically, CSF and MR imaging parameters and histopathologic data suggest that the normal-appearing white matter (NAWM) may be affected in MS but not in patients with NMO. Therefore, we hypothesized that the NAWM in NMO is normal.
  
  
  METHODS
  We studied prospectively 8 patients with clinically definitive NMO or remitting longitudinal extensive transverse myelitis (LETM) and 8 healthy controls. Ratios of N-acetylaspartate to creatine (Cr) and choline to Cr and the absolute concentrations of the metabolites were measured by chemical shift imaging with a (1)H-MR spectroscopy operating at 3T. All patients with clinically definitive NMO and LETM were found to be positive for NMO-immunoglobin G with a commercially available test.
  
  
  RESULTS
  The metabolic pattern of the NAWM of patients with NMO showed no difference compared with age- and sex-matched healthy controls.
  
  
  CONCLUSIONS
  Diffuse white matter damage is absent in NMO.
authors.affiliation: Department of Neurology, SMZ-Ost Donauspital, Vienna, Austria. fahmy.aboul-enein@chello.at
authors.forename: F
authors.initials: F
authors.lastname: Aboul-Enein
authors.forename: M
authors.initials: M
authors.lastname: Krssák
authors.forename: R
authors.initials: R
authors.lastname: Höftberger
authors.forename: D
authors.initials: D
authors.lastname: Prayer
authors.forename: W
authors.initials: W
authors.lastname: Kristoferitsch
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001921:Brain / Q000033:anatomy & histology; D005260:Female; D006801:Humans; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D008875:Middle Aged; D009471:Neuromyelitis Optica / Q000175:diagnosis*; D011446:Prospective Studies; D055815:Young Adult