Evaluation of hepatic function using 99mTc-GSA

Liver scintigraphy using technetium-99m-labeled galactosyl human serum albumin has various indices of reserve hepatic function, including LHL15 and HH15. However, these indices are subject inter-operator variation due to subjective determination of regions of interest (ROI) for the heart and liver. Therefore, the method of using an averaged ROI signal instead of an added signal was examined. The imaging data of twenty patients were evaluated by five operators using three methods: LHL15, calculated by using an added signal in ROIs of heart and liver; LHLcm15, calculated using an averaged signal in the ROIs; and LHLcm15, calculated using an averaged signal in the small circle ROI in the heart and the ROI of the liver. Inter-operator variation and the correlation with ICGR15 and with visual evaluation were evaluated for the three methods. The results indicated that the methods using averaged signal (LHLm15, LHLcm15) have little interoperator variation and have a linear correlation with other methods of determining hepatic function like ICGR15 and visual evaluation. (author)