The ultrasound phantoms used to educate medical students should not only closely mimic the ultrasound characteristics of human soft tissues but also be inexpensive and easy to manufacture. I have been studying handmade ultrasound phantoms and proposed an ultrasound phantom comprising calcium alginate hydrogel that met these requirements but caused a speckle pattern similar to that observed in ultrasound images of liver. In this study, I show that adding ethanol to the precursors used to fabricate the phantom reduces the speckle pattern. The ultrasound propagation velocity and attenuation coefficient of the phantom were 1561 ± 8 m/s and 0.54 ± 0.18 dB/cm/MHz, respectively (mean ± standard deviation), which are within the ranges of those in human soft tissues (1530-1600 m/s and 0.3-1.0 dB/cm/MHz, respectively). This phantom is easy to fabricate without special equipment, is inexpensive, and is suitable for elementary training on ultrasound diagnosis, operation of ultrasound-guided needles, and blind catheter insertion.

用于教育医学生的超声模体不仅应密切模仿人体软组织的超声特性，而且价格低廉且易于制造。我一直在研究手工制作的超声模型，并提出了一种包含海藻酸钙水凝胶的超声模型，它满足这些要求，但会产生类似于肝脏超声图像中观察到的斑点模式。在这项研究中，我表明在用于制造体模的前体中添加乙醇可以减少斑点图案。体模超声传播速度和衰减系数分别为1561±8m/s和0.54±0.18dB/cm/MHz（平均值±标准差），在人体软组织（1530-1600 m/s 和 0.3-1.0 dB/cm/MHz，分别）。