平良 淳一, 今井 康晴, 森安 史典

Junichi TAIRA, Yasuharu IMAI, Fuminori MORIYASU

東京医科大学病院消化器内科

Department of Gastroenterology and Hepatology, Tokyo Medical University, Japan

キーワード :

【Aim】
In recent years, there has been sharp increase in the use of Elasticity Imaging ultrasound technique to measure the elasticity of the tissue with many medical diagnostic devices, enabling us to distinguish tissue charaterizations. In our department, we have introduced Shear Wave Elastography （SWE）, which makes it possible to measure and display real-time quantitative tissue elasticity for Elasticity imaging. We conclude that SWE is not only useful in evaluating the degree of liver fibrosis in chronic liver diseases non-invasively, but also in diagnosing liver diseases, including acute hepatitis and hepatocellular carcinoma （HCC）.
【Method】
1）HCC: From July 2010 to August 2012, the study included 36 patients diagnosed with HCC histologically by percutaneous transhepatic needle biopsy, 24 of whom were men, and 12 of whom were women. Mean age was 70.5 8.4 （49〜84） years. Of 36 patients, modulus elasticity for 38 malignant nodules were measured . Mean tumor diameter was 21.8 16.0 （7.0〜90.0） mm. All patients consisted of 21 viral C hepatitis, 2 viral B hepatitis, 8 alcoholic liver diseases, 4 NonBNonC viral hepatitis, and 1 PBC. 2）Acute hepatitis: Modulus of elasticity was measured by SWE sequentially in two cases.
【Results】
1）HCC: The average modulus of elasticity for well-differentiated HCC was 8.2±3.4kPa（n=8）, moderately differentiated HCC 20.0±9.8kPa（n=24）, and poorly differentiated HCC 47.3±18.3kPa（n=6）. The modulus of elasticity of the tumor was significantly greater according to tumor progress （well HCC vs mod HCC; p＜0.05, well HCC vs poorly HCC; p＜0.001, mod HCC vs poorly HCC; p＜0.05）. Regarding the averaged tumor diameter, there were no significant changes, both in tumor diameter of less than 20mm（n=24） 22.3±15.0kPa, and that of 20mm （n=14） 20.9±18.0kPa （p=NS）. 2）Acute hepatitis:Modulus of elasticity of the liver was decreased with the improvement of liver dysfunction in Drug induced liver injury （12.1kPa → 10.5kPa → 8.7kPa → 7.9kPa → 5.5 kPa）, while it was increased with worsening liver dysfunction in fulminant hepatitis （16.3kPa → 25.6kPa → 38.7kPa）.
【Conclusion】
It is considered that the classification of liver fibrosis in chronic hepatitis is possible using SWE.SWE may be also a good technique to estimate severity of acute hepatitis, and grade of malignancy of HCCs.