^99mTc-GSA SPECT/CT fused images for assessment of hepatic function and hepatectomy planning

To assure safe hepatectomy, accurate estimation of the functional reserve of the future remnant liver is crucial. The combination of indocyanine green retention rate at 15 min and CT volumetry is widely used in deciding on the extent of hepatectomy. On the other hand, there are quantitative indices calculated from ^99mTc- GSA scintigraphy that reflect the number and function of hepatocytes. Therefore, there are many indices calculated from ^99mTc-GSA scintigraphy that have been reported. In recent Annals of Surgical Oncology on Oct. 2014 the Uptake Index (UI) calculated from ^99mTc-GSA scintigraphy was reported to be useful for hepatectomy planning and postoperative liver failure prediction. In this paper, we report on the usefulness and limits of quantitative indices calculated from ^99mTc-GSA SPECT/CT for preoperative simulation.