Thermoacoustic Range Verification During Delivery of a Clinical Plan by a Synchrocyclotron: transition from research prototype to turnkey clinical device

粒子治疗是一种治疗实体瘤的技术，可能比X射线放射治疗更精确。 带电粒子以相对论速度进入患者体内，当它们在体内静止时， 病人X射线光子束沿着光束路径传递指数衰减的剂量，在照射前和照射后对健康组织进行剂量给药。 肿瘤之后。 质子治疗造成的附带损害更少，并且当患者对准准确时，对健康患者的剂量更少。 近端组织和完全备用的远端组织。今天，病人的定位是通过每天的x光片中匹配的骨骼结构来实现的， X射线图像到计划CT体积采集前几天（或几周）。分次间软组织变化（体重减轻、水肿） 是常见的和组分内变化（消化、呼吸等）是不可避免的。范围错误剂量健康 组织和治疗不足的肿瘤，限制了质子治疗的好处。因此，美国治疗学会（American Society for Therapeutic 放射肿瘤学目前支持质子治疗颈部、脊柱、眼睛和儿科的肿瘤 患者，并且仅在大多数其他肿瘤部位的研究背景下。 热声量程验证依赖于应力约束，适用于紧凑型同步回旋加速器 最近由IBA和Mevion两家制造商推出。一个原型系统已经过验证，可与IBA一起使用 系统和相同的接收链已被验证为Mevion。 热声范围验证（tARV）装置的系统设计将在第三阶段完成并确认 二. tARV由一个无线超声阵列组成，周围装有六个热声接收器。紧凑 (65mm x 55 mm）数据采集（DAQ）板在10-100 ℃的热声频率范围内提供56-59 dB增益 kHz，以500 ksps采样，以最大限度地减少高频噪声的混叠，并将数据存储到板载的安全数据卡。一 紧凑型伽马探测器监测光束强度并为DAQ提供触发。 端到端验证需要与治疗计划系统（TPS）软件集成， 放射治疗诊所此外，还需要QA和临床上真实的测试对象（称为体模）。热声学 是一种结合了超声成像和放射治疗的混合技术。商业幻影设计 尚未通过放射治疗的审查。我们将整合软件，量化材料， CIRS公司已经生产的超声体模，并增加了剂量测定能力， 临床环境

Particle therapy is a technique for treating solid tumors that is potentially more precise than x-ray radiation therapy. Charged particles enter the patient at relativistic speeds, depositing increasingly more dose as they come to rest inside the patient. X-ray photon beams deliver an exponentially decaying dose along the beam path, dosing healthy tissue before and after the tumor. Proton therapy causes less collateral damage, and when patient alignment is accurate, delivers less dose to healthy proximal tissue and spares distal tissue altogether. Today, patients are positioned by matching bony structures in daily x- ray images to planning CT volumes acquired days (or weeks) prior. Inter-fraction changes to soft tissue (weight loss, edema) are common and intra-fraction changes (digestion, respiration, etc.) are unavoidable. Range errors incorrectly dose healthy tissue and undertreat the tumor, limiting benefits of proton therapy. Therefore, the American Society for Therapeutic Radiation Oncology currently supports proton therapy for tumors near the base of the neck, spine, eye and in pediatric patients, and only in the context of research studies for most other tumor sites. Thermoacoustic range verification relies upon stress confinement and is suitable for compact synchrocyclotrons recently introduced by two manufacturers, IBA and Mevion. A prototype system has been validated for use with IBA systems and the same receive chain has been validated for Mevion. System design for a thermoacoustic range verification (tARV) device will be finalized and validated during Phase II. The tARV consists of a wireless ultrasound array around which six thermoacoustic receivers are packed. A compact (65mm x 55mm) data acquisition (DAQ) board provides 56-59 dB gain over the thermoacoustic frequency range of 10-100 kHz, samples at 500 ksps to minimize aliasing of high frequency noise, and stores data to a secure data card onboard. A compact gamma detector monitors beam intensity and provides a trigger to the DAQ. End-to-end validation requires software integration with the treatment planning system (TPS) software used in radiotherapy clinics. Furthermore, QA and clinically realistic test objects, called phantoms, are required. Thermoacoustics is a hybrid technique that combines aspects of ultrasound imaging and radiation therapy. Commercial phantoms designed for ultrasound imaging have not yet been vetted for radiation therapy. We will integrate software, quantify materials in ultrasound phantoms already produced by CIRS, Inc and add dosimetric capability to enable end-to-end validation in a clinical environment.