Assessment of hepatic functional reserve for hepatic resection using 99mTc-PMT scintigraphy in comparison with 99mTc-GSA scintigraphy

99mTc-diethylenetriamine-pentaacetic acid-galactosyl human serum albumin(99mTc-GSA) scintigraphy has been reported as a useful study of hepatic functional reserve recently. We have performed 99mTc-N-pyridoxyl-5-methyl-tryptophan(99mTc-PMT) and 99mTc-GSA preoperatively for evaluation of hepatic functional reserve and compared the usefulness of those scintigraphy study. Twenty-four patients who were the candidates of hepatic resection underwent 99mTc-PMT scintigraphy preoperatively. Hepatic blood flow coefficient (K value), the amount of hepatic blood flow (HBF), and the ratio of portal blood flow (PVR) were computed. 99mTc-GSA scintigraphy was also performed within two weeks of the 99mTc-PMT scintigraphy, and the ratio of disappearance (HH15) and the hepatic uptake ratio (LHL15) were computed. The relationship between K value, HBF, PVR, HH15 and LHL15 was analyzed. Their correlation with other liver function tests was also examined. K value and HBF did not show statistically significant correlations with HH15 and LHL15, PVR correlated statistically significantly HH15 and LHL15. K value correlated with the preoperative values of cholinesterase, Fischer ratio, γ-globulin, ICGR15, albumin, and platelet count. There was a statistically significant correlation between LHL15 and the value of cholinesterase, γ-globulin, platelet count, and Fischer ratio. When the liver resection of subsegmentectomy or more was indicated in 10 patients, nine patients had LHL15 value less than 0.9 which delineated possibility of poor prognosis. However, judging from K value and HBF, liver resection was considered feasible and it was all successfully performed, resulting in good prognosis. From this study, it is suspected that 99mTc-GSA scintigraphy reflect the severity of liver fibrosis and the amount of portal blood flows, and 99mTc-PMT scintigraphy reflect the hepatic blood flow and ability of protein synthesis. It was proved that 99mTc-PMT scintigraphy is very useful for the evaluation of hepatic functional reserve. (author)