title: Cerebral diffusion tensor imaging and in vivo proton magnetic resonance spectroscopy in patients with fulminant hepatic failure.
abstract: OBJECTIVE
  Cerebral edema is a major complication in patients with fulminant hepatic failure (FHF). The aim of this study was to evaluate the metabolite alterations and cerebral edema in patients with FHF using in vivo proton magnetic resonance spectroscopy (MRS) and diffusion tensor imaging, and to look for its reversibility in survivors.
  
  
  METHODS
  Ten FHF patients along with 10 controls were studied. Five of the 10 patients who recovered had a repeat imaging after three weeks. N-acetylaspartate, choline (Cho), glutamine (Gln), glutamine/glutamate (Glx), and myoinositol ratios were calculated with respect to creatine (Cr). Mean diffusivity (MD) and fractional anisotropy (FA) were calculated in different brain regions.
  
  
  RESULTS
  Patients exhibited significantly increased Gln/Cr and Glx/Cr, and reduced Cho/Cr ratios, compared to controls. In the follow-up study, all metabolite ratios were normalized except Glx/Cr. Significantly decreased Cho/Cr were observed in deceased patients compared to controls. In patients, significantly decreased MD and FA values were observed in most topographical locations of the brain compared to controls. MD and FA values showed insignificant increase in the follow-up study compared to their first study.
  
  
  CONCLUSIONS
  We conclude that the Cho/Cr ratio appears to be an in vivo marker of prognosis in FHF. Decreased MD values suggest predominant cytotoxic edema may be present. Persistence of imaging and MRS abnormalities at three weeks' clinical recovery suggests that metabolic recovery may take longer than clinical recovery in FHF patients.
authors.affiliation: Department of Radiodiagnosis, Sanjay Gandhi Post Graduate Institute of Medical Sciences, Lucknow, India.
authors.forename: Sona
authors.initials: S
authors.lastname: Saksena
authors.forename: Vijan
authors.initials: V
authors.lastname: Rai
authors.forename: Vivek Anand
authors.initials: VA
authors.lastname: Saraswat
authors.forename: Ramkishore Singh
authors.initials: RS
authors.lastname: Rathore
authors.forename: Ankur
authors.initials: A
authors.lastname: Purwar
authors.forename: Manoj
authors.initials: M
authors.lastname: Kumar
authors.forename: M Albert
authors.initials: MA
authors.lastname: Thomas
authors.forename: Rakesh Kumar
authors.initials: RK
authors.lastname: Gupta
mesh_terms: D000293:Adolescent; D000328:Adult; D016880:Anisotropy; D001224:Aspartic Acid / Q000031:analogs & derivatives / Q000378:metabolism; D015415:Biomarkers / Q000378:metabolism; D016022:Case-Control Studies; D002560:Cerebrovascular Circulation; D002794:Choline / Q000378:metabolism*; D003401:Creatine / Q000378:metabolism*; D038524:Diffusion Magnetic Resonance Imaging; D005260:Female; D018698:Glutamic Acid / Q000378:metabolism; D005973:Glutamine / Q000378:metabolism; D006501:Hepatic Encephalopathy / Q000378:metabolism / Q000401:mortality / Q000473:pathology* / Q000503:physiopathology; D006801:Humans; D007294:Inositol / Q000378:metabolism; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D008875:Middle Aged; D010296:Parietal Lobe / Q000378:metabolism / Q000473:pathology* / Q000503:physiopathology; D011379:Prognosis; D011522:Protons; D013997:Time Factors
chemical_list: D015415:Biomarkers; D011522:Protons; D005973:Glutamine; D001224:Aspartic Acid; D018698:Glutamic Acid; D007294:Inositol; C000179:N-acetylaspartate; D003401:Creatine; D002794:Choline