Relationship Between CT Volumetry and Functional Liver Volume Using Technetium-99m Galactosyl Serum Albumin Scintigraphy in Patients Undergoing Preoperative Portal Vein Embolization Before Major Hepatectomy: A Preliminary Study

To clarify the relationship between morphological measurements of hepatic volume by computed tomography (CT-vol) and functional volume (RI-vol) by technetium-99m galactosyl human serum albumin (99mTc-GSA) scintigraphy, and its clinical significance, we examined 16 patients with a background liver status of either normal liver function (n = 4), chronic hepatitis or cirrhosis (n = 7), or obstructive jaundice (n = 5). In five patients who underwent preoperative portal vein embolization (PVE), volumetric measurement was performed 2 weeks after PVE. The mean values of CT-vol and RI-vol of the right lobe were 692± 147 cm3 (66.1 ± 10.7%) and 668 ± 159 cm3 (67.8 ± 13.2%), respectively, and those of the left lobe were 329 ± 138 cm3 (33.9 ± 10.6%) and 328± 170 cm3 (32.2 ± 13.2%), respectively. There were no significant differences in the volume measurements between the two volumetric techniques. Correlations between CT-vol and RI-vol in the right and left lobes were positive and significant (r = 0.912 and 0.903, respectively; both P′s < 0.001). The mean values of post-PVE CT-vol and RI-vol of the right lobe in five patients were significantly different (628 ± 149 and 456± 211 cm3, respectively; P = 0.033). However, the mean values of post-PVE CT-vol and RI-vol of the left lobe were not different (496 ± 124 and 483± 129 cm3, respectively). We propose that volumetric measurement by 99mTc-GSA scintigraphy is useful for detecting changes in functional volume of individual lobes of the liver and is a more dynamic method compared with detection of morphological changes by CT scan.