改井 修¹, 池田 充¹, 佐久間 貞行¹, 小西 辰男²

Osamu KAII¹, Mitsuru IKEDA¹, Sadayuki SAKUMA¹, Tatsuo KONISHI²

¹名古屋大学医学部放射線医学, ²アロカ株式会社開発五課

¹Department of Radiology, Nagoya University School of Medicine, ²Ultrasound division, Aloka Co., Ltd.

キーワード : Attenuation coefficient, Diffuse liver disease, Liver ultrasound

　We measured ultrasonic attenuation coefficients of the liver in 9 control patients and in 28 patients with diffuse liver disease. And we investigated the validity of its parameters for the clinical application. The parameters to be investgated are attenuation coefficient slope (β), frequency which gives the pseudomaximum power spectrum* (f₀), and attenuation coefficient at frequency f₀ (α(f₀)).
　The means of these estimated parameters have statistically different values among diffuse liver diseases, which is significant by one-way analysis of variance. Therefore these parameters are able to be clinically used for the diagnosis of diffuse liver diseases. Especially coefficient slope (β) is useful, which gives the lower than control values in liver cirrhosis, and the higher ones in fatty liver. It is also useful even in a nonlinear case, according to our analysis about the error in the estimation of value.
　And besides, we sought the correlation coefficients between these parameters and liver function tests. These parameters have significant positive correlation to the values, which are concerned with the liver functions of the amino acid and lipid metabolism.
　*It is a median value of the fitting frequency range of least squares used for obtaining β.