Variation in hepatic segmental portal venous pulsed wave Doppler flow distribution in patients with NAFLD: A pilot study

Purpose: To evaluate the segmental variations in portal venous pulsed wave colour Doppler flow velocity in patients with moderate to severe non-alcoholic fatty liver disease in comparison with healthy controls Materials and Methods: In this prospective, observational, case-control study, the maximum velocity of all the segmental branches of portal vein were evaluated on colour Doppler in patients with moderate to severe non-alcoholic fatty liver disease, and the values were compared between three groups (1) Healthy controls (n = 30), (2) non-alcoholic fatty liver disease group, that is moderate to severe fatty liver without features of portal hypertension (n = 32) and (3) non-alcoholic steatohepatitis-portal hypertension group, that is those non-alcoholic fatty liver disease patients with features of portal hypertension (n = 13). Results: Compared to controls, non-alcoholic fatty liver disease group showed a lower velocity in all the eight segments of liver. The ratio of segment 2 to segment 7 peak portal vein maximum velocity was significantly higher in non-alcoholic fatty liver disease (1.03 +/- 0.21) compared to controls (0.90 +/- 0.17) and even higher in non-alcoholic steatohepatitis-Portal hypertension group (1.83 +/- 0.40) with p value of 0.003. Conclusion: Our study demonstrates the occurrence of flow redistribution occurring in cases of non-alcoholic fatty liver disease patients with the left lobe receiving higher portal venous flow. This flow redistribution was even more pronounced in a subset of non-alcoholic fatty liver disease patients who developed features of portal hypertension.