Developing high-frequency ultrasound tomography for testicular tumor imaging in rats: An in vitro study

作者：Huang Chih Chung^*; Chen Wei Tsen

来源：Medical Physics, 2014, 41(1): 012902.

DOI：10.1118/1.4852915

• ultrasound computed tomography
• attenuation coefficient
• sound speed
• testicle
• small-animal imaging

Purpose: This paper describes a feasibility study for developing a 35-MHz high-frequency ultrasound computed-tomography (HFUCT) system for imaging rat testicles. %26lt;br%26gt;Methods: The performances of two kinds of HFUCT-attenuation and sound-speed UCT-based on transmission and pulse-echo modes were investigated in this study. Experiments were carried out using phantoms and actual rat testicles in vitro. HFUCT images were reconstructed using a filtered backprojection algorithm. %26lt;br%26gt;Results: The phantom experimental results indicated that all types of HFUCT can determine the dimensions of a plastic cylinder with a diameter of 500 mu m. Compared to sound-speed HFUCT, attenuation HFUCT exhibited a better performance in recognizing a tiny sclerosed region in a gelatin phantom. Therefore, the in vitro testicular experiments were performed using attenuation HFUCT based on transmission and pulse-echo modes. The experimentally measured attenuation coefficient and sound speed for healthy rat testicles were 2.92 +/- 0.25 dB/mm and 1537 +/- 25 m/s, respectively. %26lt;br%26gt;Conclusions: A homogeneous texture was evident for healthy testicles using both modes. An artificial sclerosed tumor could also be clearly observed using two-and three-dimensional attenuation HFUCT in both modes. However, an object artifact was apparent in pulse-echo mode because of ultrasound beam refraction. All of the obtained experimental results indicate the potential of using HFUCT as a novel tool for monitoring the preclinical responses of testicular tumors in small animals.

• 出版日期2014-1