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Updated: Aug 20, 2026

Harmonic Nanoparticles for Regenerative Research
Published on: May 1, 2014
A new system for in vivo assessment of the degree of nonlinear generation using the second harmonic component in echo
Yasutomo Fujii1, Nobuyuki Taniguchi, Iwaki Akiyama
1Department of Clinical Laboratory Medicine, Jichi Medical School, Tochigi 329-0498, Japan. yfujii@jichi.ac.jp
Abstract:
To assess the feasibility of a new system that uses the finite amplitude method and makes possible the assessment of the degree of nonlinear generation in vivo we adopted a method for agar-gel phantoms, using varying lipid concentrations and human livers in vivo. Instead of calculating the nonlinearity parameter B/A value, we evaluated the h value, which is determined by plotting the measured values of the ratio of the amplitude of the second harmonic component to that of the fundamental component. The agar-gel phantoms of various lipid concentrations and 20 cases of normal and 21 cases of fatty liver were studied in this investigation. There was an almost linear agreement between the h value and the lipid concentration of the phantom. The h value (mean +/- SD) was 0.25 +/- 0.03 in normal liver and 0.35 +/- 0.05 in fatty liver. A statistically significant difference was found between them (p < 0.0001). This new system was considered to be usable for evaluating h in vivo as an indicator of the lipid content of the liver.
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