title: Usefulness of Technetium-99 m-2-methoxy-isobutyl-isonitrile liver scintigraphy for evaluating disease activity of non-alcoholic fatty liver disease.
abstract: OBJECTIVE
  Non-alcoholic steatohepatitis (NASH) is a progressive form of non-alcoholic fatty liver disease (NAFLD). Therefore, it is important to evaluate disease activity and distinguish NASH from simple steatosis in NAFLD. Technetium-99 m-2-methoxy-isobutyl-isonitrile ((99m) Tc-MIBI) is a lipophilic cation designed for myocardial perfusion scintigraphy in the diagnosis of ischemic heart diseases, and its retention reflects mitochondrial function. It was reported that hepatic mitochondrial abnormalities would be an important predictive factor for NASH disease progression. The aim of this study was to examine the clinical usefulness of (99m) Tc-MIBI liver scintigraphy for evaluating disease activity of NAFLD and distinguishing NASH from simple steatosis in patients with NAFLD.
  
  
  METHODS
  Twenty-six patients with biopsy-proven NAFLD were enrolled. Clinicolaboratory tests and (99m) Tc-MIBI liver scintigraphy were performed. To evaluate hepatic uptake, regions of interest were set at the liver and heart, and the uptake ratio of the liver to heart (liver/heart ratio) was calculated.
  
  
  RESULTS
  All patients with NAFLD were classified into three groups according to the NAFLD activity score: non-NASH (simple steatosis) (n = 4), borderline NASH (n = 11), and NASH (n = 11). Liver/heart ratios were significantly lower in NASH than in simple steatosis (P < 0.05). Moreover, liver/heart ratios were significantly correlated with NAFLD activity scores among the patients (r = -0.413, P < 0.05).
  
  
  CONCLUSIONS
  The present study indicates that (99m) Tc-MIBI liver scintigraphy would be a useful non-invasive functional imaging method with which to evaluate disease activity of NAFLD and distinguish NASH from simple steatosis.
authors.affiliation: Departments of Gastroenterology and Hepatology             Radiology, Kochi Medical School, Nankoku, Kochi, Japan.
authors.forename: Kosei
authors.initials: K
authors.lastname: Masuda
authors.forename: Masafumi
authors.initials: M
authors.lastname: Ono
authors.forename: Mitsutaka
authors.initials: M
authors.lastname: Fukumoto
authors.forename: Akira
authors.initials: A
authors.lastname: Hirose
authors.forename: Kensuke
authors.initials: K
authors.lastname: Munekage
authors.forename: Tsunehiro
authors.initials: T
authors.lastname: Ochi
authors.forename: Nobuto
authors.initials: N
authors.lastname: Okamoto
authors.forename: Naoki
authors.initials: N
authors.lastname: Akagi
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Ogawa
authors.forename: Toshiji
authors.initials: T
authors.lastname: Saibara