NOVEL ULTRASONIC IMAGING OF BRACHYTHERAPY SEEDS

描述：（申请人的描述） 前列腺近距离放射治疗放射性粒子植入方法的现状 癌症依赖于B型成像来规划剂量和监测 在手术室里植入。然而，植入种子 针头导致前列腺出血、水肿和其他组织变化; 这些变化产生干扰实际种子可视化的混乱 地点由于各种原因，种子的实际位置往往 与计划的位置不同;这些差异可能导致 在实际输送的辐射剂量低于 处方剂量。然而，由于电流的能力有限， 在手术室中可视化种子的成像方法，在线校正 因为在手术过程中剂量不足。我们建议 开发新的超声成像方法， 近距离放射治疗期间，手术室中的放射性粒子， 目前的剂量计划软件，以便纠正错位的种子， 在植入过程中进行。在 在可行性评估阶段，我们将评估和 选择用于在存在下可视化种子的方法的最佳组合， 组织造成的混乱这些方法包括光谱分析， 射频超声回波信号，弹性成像分析，以及 谐波信号分析;所有这些都可以提供可以显示在 描绘种子的图像。在我们研究的发展阶段，我们 将所选方法或方法组合纳入 实时成像原型的基础上，超声波扫描仪现在使用的 纽约长老会医院放射肿瘤科（DRO） 近距离放射治疗计划与粒子植入指导中心。DRO 肿瘤学家将使用原型产生的种子图像来检测 导致剂量不足的种子错位。然后肿瘤学家会加上 以确保输送的剂量达到 处方水平，同时不超过其他地区的限制，例如 尿道，这是要保留。这些研究将由 滨江研究所（一家私营非营利研究组织）; 哥伦比亚大学（一所主要的医学研究机构）;和Spectrasonics imaging公司（一家小型商业技术公司）。

DESCRIPTION: (Applicant's Description) Current methods of implanting radioactive seeds for brachytherapy of prostate cancer rely upon B-mode imaging for planning the dose and monitoring implantation in the operating room. However, insertion of seed-implanting needles causes hemorrhage, edema, and other tissue changes in the prostate; these changes create clutter that interferes with visualization of actual seed locations. For a variety of reasons, the actual locations of seeds often differ from the planned locations; these differences may result in a considerable local reduction in the actually delivered radiation dose below the prescribed dose. However, because of the limited ability of current imaging methods to visualize seeds in the operating room, on-line correction for inadequate dosage cannot be made during the procedure. We propose to develop novel methods of ultrasonic imaging that can more effectively image seeds in the operating room during brachytherapy in a manner compatible with current dose-planning software so that corrections for misplaced seeds can be made while the implantation procedure is in progress. In the feasibility-assessment phase of our proposed study, we will evaluate and select an optimal combination of methods for visualizing seeds in the presence of tissue-caused clutter. These methods include spectrum analysis of radio-frequency ultrasonic echo signals, elastographic analysis, and harmonic-signal analysis; all can provide results that can be displayed in seed-depicting images. In the developmental phase of our proposed study, we will incorporate the selected method or combination of methods into a real-time imaging prototype based upon the ultrasonic scanner now used in the Department of Radiation Oncology (DRO) at the New York Presbyterian Medical Center for brachytherapy planning and guidance of seed implantation. DRO oncologists will use the seed images generated by the prototype to detect misplacements of seeds that cause underdosing. The oncologist then will add seeds to the seed-deprived region to assure that the delivered dose reaches the prescription level while not exceeding limits for other regions, such as the urethra, that are to be spared. These studies will be undertaken by Riverside Research Institute (a private not-for-profit research organization); Columbia University (a major medical research institution); and Spectrasonics Imaging, Inc. (a small, commercial technology corporation).