PURPOSE: To determine whether or not cerebral myo-inositol/creatine-phosphocreatine (MI/Cr) leval can beused as a criterion of hopatic encephalopathy(HE). METHODS: Single voxel stimulated echo sequence with short echotime (30 ms) was applied to parietal white matter of 14 healthy control subjects, 11 patients with chronic viral hepatitis, 29 cirrhotic patients without HE, and 33 cirrhotic patients with HE. The metabolite ratios of N-acetylaspartate (NAA), choline containing compounds (Cho), and myo-Inositol (MI) were calculated using creatine/phosphocreatine (Cr) as an internal reference. Clinical data including modified Child-pugh score, estimated serum osmolarity, and grade of HE, were obtained at the day of MR spectroscopy. RESULTS: MI/Cr was 34% lower in cirrhotic patients with HE than in control subjects. It was reduced below two standard deviation from normal in 17 of 33 cirrhotic patients with HE(52%). MI/Cr did not correlate with grade of HE(r=0.15, p=0.45) but correlate with modified Child-Pugh score(r=-0.55, p=0.00). In the analysis of Child class C patients, there was no significant difference of MI/Cr between cirrhotic patients with HE and those without HE(0.38 ±0.11, n=29 vs.0.39±0.11, n=15, p=0.59, respectively). CONCLUSION: A reduction of cerebral MI/Cr cannot be used as a diagnostic criterion of HE.