99mTc-Mebrofenin Hepatobiliary Scintigraphy with SPECT for the Assessment of Hepatic Function and Liver Functional Volume Before Partial Hepatectomy

Preoperative evaluation of future remnant liver (FRL) function is crucial in the determination of whether a patient can safely undergo liver resection. Although dynamic Tc-99m-mebrofenin hepatobiliary scintigraphy (HBS) is used to measure FRL function, 2-dimensional planar images lack the ability to assess segmental liver function. Modern SPECT/CT cameras combine dynamic Tc-99m-mebrofenin HBS with additional SPECT and the anatomic information of the CT scan. The aim of this study was to evaluate the additional value of Tc-99m-mebrofenin SPECT for the measurement of segmental liver function and liver functional volume. Methods: Preoperative CT volumetry and Tc-99m-mebrofenin HBS with SPECT were performed in 36 patients undergoing liver resection. In 18 patients, postoperative Tc-99m-mebrofenin HBS with SPECT was performed within 3 d after operation. Dual-head dynamic acquisitions were used to calculate FRL function using anterior and geometric mean (Gmean) datasets. Total and FRL functional liver volumes were measured by SPECT. Results: Because of the anatomic position of the liver, the anterior projection resulted in an underestimation of FRL function in patients undergoing left hemihepatectomy. In patients with normal liver parenchyma, total functional liver volume was comparable to total liver volume measured by CT volumetry, indicating that Tc-99m-mebrofenin SPECT is an accurate method to measure hepatic volume. In compromised livers, compared with normal livers, FRL function per cubic centimeter of liver volume was significantly less. In addition, liver function was not distributed homogeneously, with the segments to be resected relatively more affected. FRL function, measured by a combination of SPECT and dynamic HBS, was able to accurately predict actual postoperative remnant liver function. Conclusion: The Gmean dataset is recommended for the assessment of hepatic function by dynamic planar Tc-99m-mebrofenin HBS. The combination of SPECT data with the dynamic uptake function measured by planar HBS provides valuable visible and quantitative information regarding segmental liver function and is an accurate measure for FRL function.