Acoustic Radiation Force Impulse Elastometry (ARFI Elastometry) in Chronic Viral Hepatitis

Purpose: the aim of this study was to evaluate the reliability
of ARFI elastometry for diagnosis of fibrosis severity stages in patients with chronic viral hepatitis.

Material and methods. ARFI elastometry measurements were  done in 103 patients. Mean age of patients was 39.2 ± 10.8 years.  The study included 11 patients with HBV chronic hepatitis, 87  patients with HCV chronic hepatitis and 5 patients with В+D chronic  hepatitis. Liver stiffness was measured using ARFI elastometry with  following liver biopsy which was made 1–2 after US study and  assessed according to the METAVIR score. Control group included 32  patients (20 (62.5%) volunteers and 12 (37.5%) potential liver  fragment donors). Mean age of patients was 26.9 ± 5.3 years. None  of the healthy subjects had a history of gastrointestinal, pancreatic or hepatic disease; all patients had a normal results of laboratory tests.

Results. Significant correlation (r = 0.74, р < 0.001) was found  between ARFI measurements and liver fibrosis stages. The values of  ARFI elastometry for various stages of fibrosis were: F ≥ 2 – cut-off  > 1.36 m/s (AUROC – 77%, sensitivity – 65.9%, specificity – 79%),  F ≥ 3 – cut-off > 1.36 m/s (AUROC = 95%, sensitivity – 95,5%,  specificity – 81.5%), F = 4 – cut-off > 1.66 m/s (AUROC – 97%, sensitivity – 93.3%, specificity – 100%). Liver stiffness  measurements in stages F0–F2 reliably differ from stages F3–F4 (1.25 ± 0.18 m/s vs 2.0 ± 0.52 m/s, р < 0.05).

Conclusion. ARFI elastometry is reliable diagnostic method for liver  fibrosis detection in stages F ≥ 2. The best performance of this  method was shown for the prediction of severe fibrosis and cirrhosis.

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