Brief Article
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World J Gastroenterol. Jan 7, 2013; 19(1): 92-96
Published online Jan 7, 2013. doi: 10.3748/wjg.v19.i1.92
Index of convexity: A novel liver function index using Tc-GSA scintigraphy
Kenji Miki, Yuichi Matsui, Masanori Teruya, Michio Kaminishi, Norihiro Kokudo
Kenji Miki, Yuichi Matsui, Masanori Teruya, Michio Kaminishi, Department of Gastrointestinal Surgery, Showa General Hospital, Tokyo187-8510, Japan
Norihiro Kokudo, Hepato-Biliary-Pancreatic Surgery Division, Artificial Organ and Transplantation Division, Department of Surgery, Graduate School of Medicine, University of Tokyo, Tokyo 113-8655, Japan
Author contributions: Miki K designed the study, analyzed and interpreted the data, and wrote the manuscript; Matui Y collected the data; Teruya M, Kaminishi M, and Kokudo N revised the manuscript for important intellectual content pertaining to the study concept, and analysis and interpretation of data.
Correspondence to: Kenji Miki, MD, Department of Gastrointestinal Surgery, Showa General Hospital, 8-1-1 Hanakoganei, Kodaira, Tokyo 187-8510, Japan. miki-kenji@umin.ac.jp
Telephone: +81-42-4610052 Fax: +81-42-4647912
Received: August 19, 2012
Revised: October 20, 2012
Accepted: November 14, 2012
Published online: January 7, 2013
Abstract

AIM: To investigate the clinical usefulness of a newly developed index, the “index of convexity (IOC)”, for evaluating liver functional reserve using technetium-99m-diethylenetriaminepentaacetic acid-galactosyl-human serum albumin (Tc-GSA scintigraphy).

METHODS: In total, 349 patients underwent Tc-GSA scintigraphy. Dynamic planner images were obtained, and time activity curves of the liver and heart were generated and analyzed. Our focus was on the convex shape of the liver accumulation curve. We developed a method for evaluating the extent of convexity and calculated an index that we named the IOC. Clearance index and receptor index were also calculated. The correlations between each GSA index with other liver function tests and liver histopathology were evaluated.

RESULTS: Among the 3 indices generated by Tc-GSA, the IOC had the highest correlation with all other liver function tests (indocyanine green R15, albumin, prothrombin time, cholinesterase level, platelet count, and total bilirubin level). IOC can also differentiate between normal liver, chronic hepatitis, and liver cirrhosis with highest F ratio among GSA indices as determined by one-way analysis of variance. Receiver operating characteristic analysis demonstrated high diagnostic performance of IOC in the diagnosis of cirrhosis.

CONCLUSION: IOC is a very simple and reliable index for assessing liver functional reserve, which may prove to be useful in combination with the indocyanine green test for preoperative assessment of hepatic resection.

Keywords: Liver functional reserve, Preoperative assessment, Technetium-99m-diethylenetriaminepentaacetic acid-galactosyl-human serum albumin, Liver cirrhosis, Hepatectomy