[Examination of the means of measuring liver function in the hepatobiliary phase]

In a field of contrast-enhanced magnetic resonance imaging of the liver, attention has been focused on evaluation of liver function using gadolinium ethoxybenzyl diethylenetriaminepentaacetic acid(EOB). In this study, we examined the possibility of obtaining liver function in only one hepatobiliary phase 60 minutes after injection. First, in regard to the difference between the signal intensity of two materials, we examined the effects of slice gap, surface coil intensity correction(SCIC), and others. Secondly, we compared the difference between liver and spleen signal intensity with biochemical laboratory tests, Child-Pugh class, liver damage class, and the two indices(HH(15) and LHL(15))calculated by 99mTc-DTPA-galactosyl-human serum albumin hepatic scintigraphy in patients with chronic liver diseases. Finally, we designated the "Liver EOB uptake index(L-EOB(60))" from those results, compared with HH(15) and LHL(15). The results demonstrated that the difference between the signal intensity of two materials increased in the lack of slice gap explained by cross talk, and decreased with SCIC. The difference between liver and spleen signal intensity decreased with worsened liver and kidney function. In the case of slice gap >20% and direct bilirubin <0.5 mg/dL without SCIC, the correlation coefficient between L-EOB(60) and LHL(15) was 0.97. L-EOB(60) was strongly proportional to LHL(15). We conclude that L-EOB(60) meeting the above conditions can be employed as a useful index to determine liver function.