Noninvasive Diagnosis of Hepatic Fibrosis in Patients With Chronic Hepatitis C by Splenic Doppler Impedance Index

Background & Aims: The value of Doppler ultrasonography to evaluate the severity of hepatic fibrosis in patients with chronic hepatitis C (CHC) remains controversial. Methods: Consecutive histologically proven patients with CHC over a 4-year period were divided into training (n = 335) and validation (n = 168) sets. Hepatic Doppler impedance index, splenic Doppler impedance index, and mean portal vein velocity were evaluated for all patients before liver biopsies. Multivariate logistic regression was performed to find the independent factors to predict patients with significant fibrosis (≥F2) and cirrhosis (F4) in the training set. Receiver operating characteristic curves were constructed for these factors to evaluate the diagnostic accuracy of significant hepatic fibrosis and cirrhosis in the training set, and in the validation set to evaluate the reproducibility. Results: Multivariate logistic regression revealed that the splenic arterial pulsatility index (SAPI) and the mean portal vein velocity were predictive of significant fibrosis (≥F2) and cirrhosis (F4). Receiver operating characteristic analysis showed the areas under the curves of regression models and SAPI were comparable in predicting significant fibrosis (0.88 vs 0.87, P = .22) and cirrhosis (0.92 vs 0.90, P = .12) in the training set. Areas under the curves of SAPI were 0.89 and 0.92 in predicting significant hepatic fibrosis and cirrhosis in the validation set. By choosing optimized cut-off levels, 54% and 76% of the patients with significant hepatic fibrosis and cirrhosis could be predicted correctly. Conclusions: SAPI is accurate and reproducible for assessing the severity of hepatic fibrosis in patients with CHC. Applying this simple Doppler index can decrease the need for staging liver biopsy.

Abbreviations used in this paper: AUC, area under receiver operating characteristic, CHC, chronic hepatitis C, CI, confidence interval, DA, diagnostic accuracy, DDU, duplex Doppler ultrasonography, HAPI, hepatic arterial pulsatility index, HARI, hepatic arterial resistive index, OR, odds ratio, PVV, portal vein velocity, ROC, receiver operating characteristic, SAPI, splenic arterial pulsatility index, SARI, splenic arterial resistive index