A precise and thorough methodology is presented for the design and fabrication of bimodal phantoms to be used in medical microwave and ultrasound applications. Dielectric and acoustic properties of human soft tissues were simultaneously mimicked. The phantoms were fabricated using polyvinyl alcohol cryogel (PVA-C) as gelling agent at a 10% concentration. Sucrose was employed to control the dielectric properties in the microwave spectrum, whereas cellulose was used as acoustic scatterer for ultrasound. For the dielectric properties at microwaves, a mathematical model was extracted to calculate the complex permittivity of the desired mimicked tissues in the frequency range from 500 MHz to 20 GHz. This model, dependent on frequency and sucrose concentration, was in good agreement with the reference Cole–Cole model. Regarding the acoustic properties, the speed of sound and attenuation coefficient were employed for validation. In both cases, the experimental data were consistent with the corresponding theoretical values for soft tissues. The characterization of these PVA-C phantoms demonstrated a significant performance for simultaneous microwave and ultrasound operation. In conclusion, PVA-C has been validated as gelling agent for the fabrication of complex multimodal phantoms that mimic soft tissues providing a unique tool to be used in a range of clinical applications.

提出了一种精确而彻底的方法，用于设计和制造用于医疗微波和超声应用的双模体模型。同时模拟人体软组织的介电和声学特性。使用聚乙烯醇冷冻凝胶 (PVA-C) 作为浓度为 10% 的胶凝剂制造模型。蔗糖用于控制微波频谱中的介电特性，而纤维素则用作超声波的声散射体。对于微波的介电特性，提取了一个数学模型来计算所需模拟组织在 500 MHz 至 20 GHz 频率范围内的复介电常数。该模型取决于频率和蔗糖浓度，与参考科尔-科尔模型非常一致。对于声学特性，采用声速和衰减系数进行验证。在这两种情况下，实验数据与软组织的相应理论值一致。这些 PVA-C 模型的表征证明了同步微波和超声操作的显着性能。总之，PVA-C 已被验证为胶凝剂，可用于制造模仿软组织的复杂多模态模型，为一系列临床应用提供了独特的工具。