Abstract: Objective The aim of this study was to investigate the influence of age on intrarenal resistance index（RI）in patients with nonalcoholic fatty liver disease（NAFLD）. Methods 178 patients with NAFLD underwent a conventional abdominal ultrasound and color Doppler flower imaging（CDFI）examination. CDFI signals were taken from arcuate arteries of the cortex in the right and left kidneys,respectively. Results Patients with NAFLD had an increased length of left kidney（P<0.01）and a decreased RI in left than right（P<0.05）;The variable age showed a significant positive correlation on both arcuate arteries. Conclusion Patients with NAFLD show age dependency on arcuate arteries RI and have an lower value than in healthy adults.

Key words: Nonalcoholic fatty liver disease, Resistance index, Ultrasound