title: Abnormal baseline brain activity in patients with neuromyelitis optica: a resting-state fMRI study.
abstract: OBJECTIVE
  Recent immunopathologic and MRI findings suggest that tissue damage in neuromyelitis optica (NMO) is not limited to spinal cord and optic nerve, but also in brain. Baseline brain activity can reveal the brain functional changes to the tissue damages and give clues to the pathophysiology of NMO, however, it has never been explored by resting-state functional MRI (fMRI). We used regional amplitude of low frequency fluctuation (ALFF) as an index in resting-state fMRI to investigate how baseline brain activity changes in patients with NMO.
  
  
  METHODS
  Resting-state fMRIs collected from seventeen NMO patients and seventeen age- and sex-matched normal controls were compared to investigate the ALFF difference between the two groups. The relationships between ALFF in regions with significant group differences and the EDSS (Expanded Disability Status Scale), disease duration were further explored.
  
  
  RESULTS
  Our results showed that NMO patients had significantly decreased ALFF in precuneus, posterior cingulate cortex (PCC) and lingual gyrus; and increased ALFF in middle frontal gyrus, caudate nucleus and thalamus, compared to normal controls. Moderate negative correlations were found between the EDSS and ALFF in the left middle frontal gyrus (r=-0.436, p=0.040) and the left caudate (r=-0.542, p=0.012).
  
  
  CONCLUSIONS
  The abnormal baseline brain activity shown by resting-state fMRI in NMO is relevant to cognition, visual and motor systems. It implicates a complex baseline brain status of both functional impairments and adaptations caused by tissue damages in these systems, which gives clues to the pathophysiology of NMO.
authors.affiliation: Department of Radiology, Xuanwu Hospital, Capital Medical University, Beijing 100053, PR China.
authors.forename: Yaou
authors.initials: Y
authors.lastname: Liu
authors.forename: Peipeng
authors.initials: P
authors.lastname: Liang
authors.forename: Yunyun
authors.initials: Y
authors.lastname: Duan
authors.forename: Xiuqin
authors.initials: X
authors.lastname: Jia
authors.forename: Fei
authors.initials: F
authors.lastname: Wang
authors.forename: Chunshui
authors.initials: C
authors.lastname: Yu
authors.forename: Wen
authors.initials: W
authors.lastname: Qin
authors.forename: Huiqing
authors.initials: H
authors.lastname: Dong
authors.forename: Jing
authors.initials: J
authors.lastname: Ye
authors.forename: Kuncheng
authors.initials: K
authors.lastname: Li
mesh_terms: D000328:Adult; D001931:Brain Mapping / Q000379:methods; D016022:Case-Control Studies; D004185:Disability Evaluation; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009471:Neuromyelitis Optica / Q000503:physiopathology*