A noninvasive method for measuring portal venous/total hepatic blood flow by hepatosplenic radionuclide angiography.

Radionuclide angiography was used to generate first-pass radioactivity vs. time curves for the left heart, right hepatic lobe, right lung, spleen, and both kidneys following rapid intravenous injection of 20 mCi (740 MBq) of 99mTc-pertechnetate. Seven normal subjects were examined as well as 57 cirrhotic patients, who also underwent angiographic grading of portal venous perfusion. For analysis, two time points were identified: (a) t0, when 99mTc first entered the liver (the initial rise of either curve); and (b)tc, when 99mTc was maximal in abdominal organs (the renal peak). Analysis was based on the slopes of the two phases of the hepatic curves t0 + 7 seconds and Tc + 7 seconds; this time selection permitted analysis of all curves. The hepatic perfusion index (HPI) = slope (tc + 7 secs)/slope (t0 + 7 secs) + slope (tc + 7 secs). The mean HPI for the normal subjects was 66% +/- 7; for the cirrhotic patients with angiographic Grades I, II, III, and IV, the HPI was 52% +/- 9, 37% +/- 6, 15% +/- 7, and 3% +/- 4, respectively. Correlation between HPI and angiography was significant (p less than 0.001). This method offers a readily available, rapid, relatively inexpensive, and quantitative method of grading the ratio of portal venous to total hepatic blood flow.