Wang Shutao, Frenkel Victor, Zderic Vesna
Department of Electrical and Computer Engineering, The George Washington University, Washington, DC 20052, USA.
Annu Int Conf IEEE Eng Med Biol Soc. 2009;2009:3055-9. doi: 10.1109/IEMBS.2009.5333582.
Due to its high degree of accuracy and non-invasive implementation, pulsed-high intensity focused ultrasound (HIFU) is a promising modality for hyperthermia applications as adjuvant therapy for cancer treatment. However, the relatively small focal region of the HIFU beam could result in prohibitively long treatment times for large targets requiring multiple exposures. In this work, finite element analysis modeling was used to simulate focused ultrasound propagation and the consequent induction of hyperthermia. The accuracy of the simulations was first validated with thermocouple measurements in hydrogel phantoms. More advanced simulations of in vivo applications using single HIFU exposures were then done incorporating complex, multi-layered tissue composition and variable perfusion for an in vivo murine xenograft tumor model. The results of this study describe the development of a preliminary methodology for optimizing spatial application of hyperthermia, through the evaluation of different HIFU exposures. These types of simulations, and their validations in vivo, may help minimize treatment durations for pulsed-HIFU induced hyperthermia and facilitate the translation of these exposures into the clinic.
由于其高度的准确性和非侵入性实施方式，脉冲高强度聚焦超声（HIFU）作为癌症治疗辅助疗法的热疗应用是一种很有前景的方式。然而，HIFU束相对较小的聚焦区域可能导致对于需要多次照射的大目标而言治疗时间长得令人望而却步。在这项工作中，使用有限元分析模型来模拟聚焦超声传播以及由此引发的热疗。首先通过在水凝胶体模中的热电偶测量来验证模拟的准确性。然后针对体内小鼠异种移植肿瘤模型，结合复杂的多层组织成分和可变灌注，对使用单次HIFU照射的体内应用进行了更先进的模拟。本研究结果描述了一种初步方法的开发，该方法通过评估不同的HIFU照射来优化热疗的空间应用。这类模拟及其在体内的验证可能有助于将脉冲HIFU诱导热疗的治疗时间减至最短，并促进将这些照射方法转化到临床应用中。
