Yuko Kanayama

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.

P21.04: Usefulness of standard deviation on the histogram of ultrasound as a quantitative value for intra ovarian tumor fluid echo texture; preliminary study

Introduction: The mature cystic teratomas account for about 40–50% of all benign ovarian neoplasias. Over 80% of teratomas occur during the reproductive phase, in which women are usually asymptomatic. Ultrasound examination remains an extremely sensitive method in the diagnosis of mature teratoma. Case Report: SPB, 11 years old, apparently healthy, went to the GP in January 2009 by an increasing abdominal volume for the past six months. No other symptoms. Performed abdominal and pelvic endocavitary ultrasound, which showed: Extensive abdominal mass, right located, with cystic component and multiple regular septa, without papilla and with normal Doppler. Other abdominal and pelvic organs without structural changes. Right ovary not seen. Laboratory showed elevation of the following tumor markers: CEA (73.6 U/ml); CA 125 (73.60 U/ml) and CA 19.9 (4145 U/ ml). Surgery in February 2009 in our hospital: removal of a giant mass (about 3kg), occupying six abdominal quadrants in relation to right ovary. Other abdominal organs without macroscopic changes. Histologically, it was confirmed the presence of a right ovary mature teratoma (benign trigerminoma). Maintains follow-up in surgery consultation: clinically well, without signs of recurrence. Postoperative tumor markers normalized. Final Comment: In this case, the sonographic suspicion of a benign lesion was confirmed histologically, in the context of tumor with markers significantly changed (specifically the CA 19.9) and rapid growth.