title: Grey and white matter abnormalities in minimal hepatic encephalopathy: a study combining voxel-based morphometry and tract-based spatial statistics.
abstract: OBJECTIVE
  Low-grade cerebral oedema is considered to be pathognomonic of minimal hepatic encephalopathy (MHE) in cirrhotic patients. The purpose of this study was to investigate both the grey matter (GM) and white matter (WM) changes in a homogeneous cohort of patients with MHE by combining voxel-based morphometry (VBM) and tract-based spatial statistics (TBSS).
  
  
  METHODS
  Twenty-five MHE patients and 25 healthy controls participated in the study with three-dimensional T1 and diffusion-tensor imaging. Group differences in regional GM volume were assessed using VBM analysis while differences in fractional anisotropy (FA), mean diffusivity (MD) of WM were compared using TBSS analysis.
  
  
  RESULTS
  VBM displayed extensively decreased GM volume in MHE, mainly located in the frontal and temporal cortices, paracentral lobule, caudate, putamen and amygdale, and increased GM volume in the thalamus. TBSS showed decreased FA in MHE patients in the corpus callosum, cingulum, internal/external capsule, corticospinal tract, superior longitudinal fasciculus and posterior corona radiata. Areas of increased MD in MHE patients were more extensive and included, in addition to all the areas of decreased FA, the anterior corona radiata, inferior fronto-occipital fasciculus, fornix and the middle cerebellar peduncle.
  
  
  CONCLUSIONS
  The results suggest that cortical atrophy and low-grade brain oedema in WM co-exist in MHE.
authors.affiliation: Department of Medical Imaging, Jinling Hospital, Clinical School of Medical College, Nanjing University, 305 Zhongshan East Road, Xuanwu District, Nanjing, Jiangsu Province, 210002, China.
authors.forename: Rongfeng
authors.initials: R
authors.lastname: Qi
authors.forename: Long Jiang
authors.initials: LJ
authors.lastname: Zhang
authors.forename: Jianhui
authors.initials: J
authors.lastname: Zhong
authors.forename: Tong
authors.initials: T
authors.lastname: Zhu
authors.forename: Zhiqiang
authors.initials: Z
authors.lastname: Zhang
authors.forename: Chuanjian
authors.initials: C
authors.lastname: Xu
authors.forename: Gang
authors.initials: G
authors.lastname: Zheng
authors.forename: Guang Ming
authors.initials: GM
authors.lastname: Lu
mesh_terms: D016880:Anisotropy; D001284:Atrophy / Q000473:pathology; D001921:Brain / Q000473:pathology; D001929:Brain Edema / Q000150:complications / Q000473:pathology*; D002531:Cerebellum / Q000473:pathology; D003337:Corpus Callosum / Q000473:pathology; D056324:Diffusion Tensor Imaging; D005260:Female; D005625:Frontal Lobe / Q000473:pathology; D006501:Hepatic Encephalopathy / Q000150:complications / Q000473:pathology*; D006801:Humans; D008103:Liver Cirrhosis / Q000150:complications; D008297:Male; D008875:Middle Aged; D009413:Nerve Fibers, Myelinated / Q000473:pathology*; D011446:Prospective Studies; D011712:Pyramidal Tracts / Q000473:pathology; D013702:Temporal Lobe / Q000473:pathology