title: Comparative brain stem lesions on MRI of acute disseminated encephalomyelitis, neuromyelitis optica, and multiple sclerosis.
abstract: BACKGROUND
  Brain stem lesions are common in patients with acute disseminated encephalomyelitis (ADEM), neuromyelitis optica (NMO), and multiple sclerosis (MS).
  
  
  OBJECTIVE
  To investigate comparative brain stem lesions on magnetic resonance imaging (MRI) among adult patients with ADEM, NMO, and MS.
  
  
  METHODS
  Sixty-five adult patients with ADEM (n = 17), NMO (n = 23), and MS (n = 25) who had brain stem lesions on MRI were enrolled. Morphological features of brain stem lesions among these diseases were assessed.
  
  
  RESULTS
  Patients with ADEM had a higher frequency of midbrain lesions than did patients with NMO (94.1% vs. 17.4%, P<0.001) and MS (94.1% vs. 40.0%, P<0.001); patients with NMO had a lower frequency of pons lesions than did patients with MS (34.8% vs. 84.0%, P<0.001) and ADEM (34.8% vs. 70.6%, P = 0.025); and patients with NMO had a higher frequency of medulla oblongata lesions than did patients with ADEM (91.3% vs. 35.3%, P<0.001) and MS (91.3% vs. 36.0%, P<0.001). On the axial section of the brain stem, the majority (82.4%) of patients with ADEM showed lesions on the ventral part; the brain stem lesions in patients with NMO were typically located in the dorsal part (91.3%); and lesions in patients with MS were found in both the ventral (44.0%) and dorsal (56.0%) parts. The lesions in patients with ADEM (100%) and NMO (91.3%) had poorly defined margins, while lesions of patients with MS (76.0%) had well defined margins. Brain stem lesions in patients with ADEM were usually bilateral and symmetrical (82.4%), while lesions in patients with NMO (87.0%) and MS (92.0%) were asymmetrical or unilateral.
  
  
  CONCLUSIONS
  Brain stem lesions showed various morphological features among adult patients with ADEM, NMO, and MS. The different lesion locations may be helpful in distinguishing these diseases.
authors.affiliation: Department of Neurology, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, China.
authors.forename: Zhengqi
authors.initials: Z
authors.lastname: Lu
authors.forename: Bingjun
authors.initials: B
authors.lastname: Zhang
authors.forename: Wei
authors.initials: W
authors.lastname: Qiu
authors.forename: Zhuang
authors.initials: Z
authors.lastname: Kang
authors.forename: Liping
authors.initials: L
authors.lastname: Shen
authors.forename: Youming
authors.initials: Y
authors.lastname: Long
authors.forename: Junqi
authors.initials: J
authors.lastname: Huang
authors.forename: Xueqiang
authors.initials: X
authors.lastname: Hu
mesh_terms: D000293:Adolescent; D000328:Adult; D001933:Brain Stem / Q000473:pathology*; D003710:Demography; D004673:Encephalomyelitis, Acute Disseminated / Q000473:pathology*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000473:pathology*; D009471:Neuromyelitis Optica / Q000473:pathology*; D013116:Spinal Cord / Q000473:pathology; D055815:Young Adult