Iodine-125 Peripheral Intravascular Brachytherapy System

描述(申请人提供)：周围血管动脉再狭窄是常见的、病态的和昂贵的。最初的治疗方法主要集中在药物、机械设备(动脉粥样硬化切除或组织切除)、物理设备(支架植入)和基因治疗。所有这些都没有成功。最近在冠状动脉血管系统中使用药物洗脱支架的成功也尚未转化为外周血管系统。再狭窄一直是PTA的致命弱点。 目前的研究表明，使用后装192 Ir源的血管内近距离放射治疗对治疗股动脉和月国动脉再狭窄具有良好的效果。这项技术的缺点是，在插管实验室进行血管成形术的患者必须用原位导管运送到进行近距离放射治疗的放射肿瘤学设施。这个项目的目的是证明使用低能量的125-碘的血管内近距离治疗系统将与使用高能量的192-Ir的现有系统一样安全和有效，并将适合于在导管实验室内进行外周血管内近距离治疗。 这一目标的实现将通过a)设计和制造适合用于外周血管内治疗的形式的合适的高活性125-碘来源，以及b)完成评估原型来源的安全性和剂量学效果的研究。 该计划的主要好处将是开发一种源和屏蔽系统，允许在不移动患者及其附带风险的情况下执行近距离放射治疗，并在手术过程中保持患者在心脏病专家的监督下。我们预计，这一发展将把外周血管内近距离放射治疗的使用扩展到更多的医院中心。

DESCRIPTION (provided by applicant): Restenosis of the peripheral vascular arteries is common, morbid and expensive. Initial therapeutic approaches have focused on pharmaceutical agents, mechanical devices (atherectomy or tissue removing), physical devices (stenting) and gene therapy. None of these have been successful. Nor have the recent success surrounding the use of drug-eluting stents in the coronary vascular system yet been translated to the peripheral vascular system. Restenosis has been the Achilles heel of PTA. The current research has shown that intravascular brachytherapy using afterloaded 192-Iridium sources has a beneficial effect of the treatment of restenosis in femoral and popliteal arteries. The drawback to this technique is that patients who have angioplasty performed in the catheterization laboratory must be transported with catheter in situ to the radiation oncology facility where brachytherapy is performed. The aim of this project is to demonstrate that an intravascular brachytherapy system for treatment of peripheral arteries that uses a low-energy source of 125-Iodine will be as safe and effective as the existing system that uses a high-energy source of l92-lridium, and will be suitable to permit the performance of peripheral intravascular brachytherapy within the catheterization laboratory. The accomplishment of this objective will be demonstrated by a) the design and fabrication of a suitable high activity 125-lodine source in the form suitable for delivery for peripheral intravascular treatment, and b) the completion of studies that evaluate the safety and dosimetric efficacy of the prototype source. The principal benefit of this program will be the development of a source and shielding system that will permit the performance of brachytherapy without movement of the patient and its collateral risk, and keep the patient under the supervision of the cardiologist during the procedure. We anticipate that this development will extend the use of peripheral intravascular brachytherapy to a much larger number of hospital centers.