Objective and Methods: To evaluate the effects of portal blood flow on liver function, this pilot study investigated the correlation between changes in portal blood flow as measured by image-directed Doppler ultrasonography and liver function tests in nine patients with cirrhosis who were treated with balloon-occluded retrograde transvenous obliteration, All patients had large gastric varices and prominent gastrorenal shunts, Results: Treatment caused a significant increase (p < 0.01) in portal blood flow; we documented reversion from hepatofugal to hepatopetal portal flow in one patient and increases in hepatopetal flow from 5.4 +/- 1.1 to 7.85 +/- 1.4 cm/s (mean +/- SD) in eight patients. All patients showed decreases in gastric variceal size, However, portal pressure rose significantly in all patients after treatment from 25.4 +/- 7.6 to 30.7 +/- 5.8 mmH(2)O (n = 7, mean +/- SD), and two of nine patients had worsening of esophageal varices, All nine patients showed improvement in the 15-min retention rate of indocyanine green from 31.8 +/- 16.1 to 21.8 +/- 12.4% (mean +/- SD, p < 0.01), whereas seven patients showed increased serum albumin levels after treatment, Conclusions: These results suggest balloon-occluded retrograde transvenous obliteration increases hepatic portal blood flow, which may be accompanied by improvements in liver function.