TEMPERATURE AND ACOUSTIC FEEDBACK/THERAPEUTIC ULTRASOUND

本修订申请中研究的广泛长期目标 是开发完全无创的超声引导相控阵 用于一系列治疗应用的施用器系统，例如， 热疗、快速加热热疗和组织消融。 我们 初步研究结果表明，非侵入性测量 组织温度的变化是可行的，使用标准诊断 超声脉冲回波数据和适当的数字信号处理 (DSP)算法我们已经通过实验证实， 可以精确地估计温度并具有高空间分辨率 通过估计RF脉冲回波数据的频谱中的频移 在特定的位置。 此外，非侵入性声反馈用于 通过组织不均匀性聚焦和目标（肿瘤）跟踪， 也可行。这就需要新的阶段性发展-- 能够发射-接收操作的阵列施加器系统。传送- 接收能力将使相控阵列施加器能够自我 在存在组织不均匀性的情况下聚焦， 成像阵列目前在实践中使用。自聚焦治疗 阵列，虽然在原理上类似于成像阵列的自聚焦， 确实带来了一些新的挑战我们打算发展自我聚焦 最佳治疗阵列的算法。无创测量 温度变化和治疗的自聚焦能力 结合使用实时超声成像的引导的施用器 系统无疑将为透热疗法提供一个有吸引力的系统， 组织消融（手术）。多功能、低成本、低发病率 与非侵入性超声程序相关的将具有积极的 对大量患者的医疗保健服务产生影响 组，例如，乳腺癌、前列腺癌和肝癌。

The broad long-term objective of the research in this revised application is to develop completely noninvasive ultrasound-guided phased-array applicator systems for, a range of therapeutic applications, e.g., hyperthermia, rapid-heating hyperthermia, and tissue ablation. Our preliminary research results indicate that noninvasive measurement of changes in tissue temperature is feasible using standard diagnostic ultrasound pulse-echo data and appropriate digital signal processing (DSP) algorithms. We have experimentally verified that changes in tissue temperatures can be estimated accurately and with high spatial resolution by estimating frequency shifts in the spectrum of the RF pulse-echo data at a specified location. Furthermore, noninvasive acoustic feedback for focusing and target (tumor) tracking through tissue inhomogeneities is also feasible. This, however, requires the development of new phased- array applicator systems capable of transmit-receive operation. Transmit- receive capability will give phased-array applicators the ability to self focus in the presence of tissue inhomogeneity in a similar manner to imaging arrays currently used in practice. Self-focusing of therapeutic arrays, while similar in principle to self-focusing of imaging arrays,, does present some new challenges. We intend to develop self-focusing algorithms for optimal therapeutic arrays. Noninvasive measurement of temperature changes and self-focusing capability of therapeutic applicators coupled with guidance using real-time ultrasound imaging systems will undoubtedly provide an attractive system for diathermy and tissue ablation (surgery). The versatility, low cost, and low morbidity associated with noninvasive ultrasonic procedure will have a positive impact on the health care delivery for a significant number of patient groups, e.g., breast cancer, prostate cancer, and liver cancers.