RESUMO
OBJECTIVE: To evaluate the diagnostic performance of acoustic radiation force impulse imaging (ARFI) in detecting significant hepatic fibrosis in children. MATERIAL AND METHODS: Our hospital's ethics committee approved the study and all patients or their representatives provided informed written consent. We included 96 children (50 boys, 46 girls; mean age, 8 y). We also studied 16 volunteers without liver disease as controls and 80 patients with diseases that can lead to fibrosis and cirrhosis of the liver. The final sample included 31 patients with biopsies and the 16 controls. All patients underwent abdominal ultrasonography including Doppler imaging and elastography with ARFI. The ARFI value, expressed as velocity (m/s) of shear wave propagation through the tissue, was calculated by averaging 16 measurements in both liver lobes. We used one-way analysis of variance to compare means between groups; we set statistical significance at P<.05. We used Student's t-tests and chi-square tests for categorical data. RESULTS: The ARFI value in children with fibrosis ≥ F2 was higher (1.80±0.45m/s) than in controls and higher than in patients with F0-F1 (1.38±0.22m/s). The difference was significant (P<.001) for detecting F ≥ 2. Steatosis was not related with the ARFI value (Student's t-test, P>.84). Necroinflammatory activity was strongly associated with the ARFI value (Student's t-test, P<.01). Fibrosis and necroinflammatory activity were strongly associated with each other (chi-square test, P<.0001). CONCLUSION: The speed of shear wave propagation is significantly associated with the degree of hepatic fibrosis in children.
