Usefulness of evaluating hepatic elasticity using artificial acoustic radiation force ultrasonography before hepatectomy

AIM: To evaluate hepatic fibrosis and tumor diagnosis preoperatively, we investigated the elasticity calculated by the new parameter of ultrasonography, acoustic radiation force impulse (ARFI). METHODS: We examined ARFI of the non-tumorous right and left lateral liver and in the tumor by push pulse of probe in 95 patients with hepatic malignancies undergoing hepatectomy. Measurement of ARFI as hepatic stiffness was indicated as the Vs (m/s). RESULTS: Measuring the Vs in the non-tumor region was achieved in the right liver in 99% and at the left lateral liver in 94%. The Vs in the right liver was significantly lower than in the left lateral liver, and the Vs of the liver tumor was significantly higher than in the non-tumorous liver. The Vs in the right and left lateral liver was correlated with the platelet count, aspartate aminotransferase, fibrotic indices and indocyanine green test. The Vs in the right liver was significantly correlated with the fibrotic marker or index. The Vs of liver cirrhosis and histological stage 4 in the right and left liver was significantly the highest compared to the others. The Vs in the right liver showed a high area under the receiver-operator curve value predicting histological fibrosis. The Vs in the right was significantly correlated with blood loss and postoperative complications, particularly uncontrolled ascites. CONCLUSION: Non-invasive ARFI imaging elastography is useful in evaluating impaired liver function or in the differential diagnosis of liver malignancies, highly hepatic fibrosis and in predicting posthepatectomy morbidity.