PROSTATE CANCER AND BPH ABLATION USING HIFU WAVEGUIDE

简介(改编自申请人摘要)：建议的申请人 设计并制作了一种经尿路声导系统。 良性前列腺异常组织的消融治疗 前列腺肥大(BPH)和前列腺癌。一般的方法 就是采用声导和经尿道途径 将高强度聚焦超声(HIFU)应用于前列腺。 申请者提议首先开发一种原型波导器 使用大型外部换能器的系统可产生高电平的声波 能量将被传递到前列腺癌 波导，并在前列腺内形成足够锐利的焦点 以引起热消融。波导型系统有可能是 可使治疗焦点沿3个自由度移动 为了将超声波能量传递到 以可控制的方式切除前列腺。申请者将会 用声场标测技术评估体外波导系统 纹影摄影过程，以及在体模和切除的研究中 组织，并将从以下方面确定最佳治疗方案 对系统施加的电力，最有效 移动波导焦点的技术和最好的方法 用于冷却和保护附近敏感的正常结构 使用循环水洗澡的前列腺。随后对狗进行的评估 将使用被确定为 最优来自体外的工作，以评估能力 在活体内产生受控前列腺消融的设备，并 评估对邻近前列腺周围组织的损害程度。全 将使用新的磁共振热像仪进行幻影和动物研究 用于监测组织加热的标测技术。这些技术将 包括快速T1加权和相敏磁共振成像 这个应用程序。在这项工作完成后，申请人预计 开发和测试了一种声波导管系统，具有 核磁共振热图引导下的超声投射，具有 高效微创治疗良性前列腺增生症的潜力 以及前列腺癌的局部控制。

DESCRIPTION (Adapted from Applicant's Abstract): The applicants proposed to design and fabricate a transurethral acoustic waveguide system for the ablation of abnormal human prostatic tissue involved with benign prostatic hypertrophy (BPH) and prostate cancer. The general approach would be to employ an acoustic waveguide and a transurethral approach to apply high-intensity focused ultrasound (HIFU) to the prostate gland. The applicants proposed to begin by developing a prototype waveguide system using a large external transducer to create high levels of sonic energy which would be transmitted to the prostate gland by the waveguide, and brought to a sufficiently sharp focus within the prostate to cause thermal ablation. The waveguide system would potentially be capable of moving the treating focal spot along 3 degrees of freedom so as to translate the ultrasonic energy through the regions of the prostate to be ablated in a controlled manner. The applicants would evaluate the waveguide system in vitro by acoustic field mapping using a Schlieren photographic process, and in studies of phantoms and excised tissues, and would determine an optimal treatment protocol in terms of the electrical power applied to the system, the most effective techniques for moving the focal spot of the waveguide, and the best way in which to cool and protect sensitive normal structures near the prostate using a circulating water bath. Subsequent evaluations in dogs would be performed with the insonification protocol determined to be most optimal from the in vitro work, in order to evaluate the ability of the device to produce controlled prostatic ablation in vivo, and to assess the degree of damage to adjacent periprostatic tissues. All phantom and animal studies would be performed with new MR thermal mapping techniques for monitoring tissue heating. These techniques would include rapid T1-weighted and phase-sensitive MR imaging optimized for this application. Upon completion of this work, the applicants expect to have developed and tested an acoustic waveguide system, with ultrasonic delivery guided by thermal mapping with MRI, that has the potential for highly effective and minimally invasive treatment of BPH and local control of prostate cancer.