Real-time ultrasound attenuation imaging of diffuse fatty liver disease.

A method for real-time ultrasound attenuation imaging and quantification is proposed in this paper. We employed a simple algorithm for comparing two signal intensities of different frequencies to extract attenuation quantitatively. The usefulness of this method was verified by numerical simulation of the acoustic field and validated by phantom experiments. The accuracy of the results was reduced by noise in areas with a low signal-to-noise ratio, but we found that the effects of noise could be reduced by applying our noise cancellation technique or simply setting a sufficiently high gain. The estimated attenuation coefficients for clinical liver images showed acceptable correlation with the liver-to-spleen ratio of computed tomography numbers. These findings suggest that real-time attenuation parametric imaging may be able to replace CT for quantifying the degree of fatty infiltration of the liver. However, further development is needed to obtain the local attenuation distribution in cross sections with sufficient reliability.