A simple method for evaluating liver fibrosis in NAFLD using quantified hepatic venous waveform

【Background】
There is an urgent need to enclose high-risk NAFLD cases with advanced fibrosis. The hepatic vein (HV) waveform by Doppler ultrasound flattens with liver fibrosis progression and we have previously reported a simple method to diagnose liver fibrosis using quantified HV waveform (Ultrasound Med Biol. 2019). In this study, we investigated the usefulness of HV waveform in evaluating liver fibrosis in NAFLD.
【Methods and Results】
We calculated the coefficient of variation (CV) of the HV flow velocity and created an index “q-HV” (the inverse of CV value) in 124 biopsy-proven NAFLD patients. The CV value was associated with flattening of the waveform, and the q-HV significantly increased with the progression of fibrosis. The AUCs of q-HV for prediction of F2, F3, and F4 were 0.725, 0.776, and 0.801, respectively. We examined the influence of inflammation and fat deposition on the diagnostic ability of q-HV; the AUC for detecting F2 was 0.819 in cases with lobular inflammation score ≥2 (n=71), and 0.733 in cases with steatosis score ≥2 (n=60).
【Conclusion】
The diagnostic performance of q-HV for liver fibrosis in NAFLD is good enough, even in cases with severe inflammation or fat deposition. It may be a versatile method for diagnosing liver fibrosis in NAFLD.