Iodine-125 Peripheral Intravascular Brachytherapy System

描述（由申请人提供）：周围血管动脉的再狭窄是常见的、病态的和昂贵的。最初的治疗方法集中在药物制剂，机械设备（斑块切除术或组织去除），物理设备（支架）和基因治疗。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没有被转移到外周血管系统。缓刑一直是PTA的致命弱点。 目前的研究表明，使用后装192-铱源的血管内近距离放射治疗对股动脉和腘动脉的再狭窄具有有益的治疗效果。该技术的缺点是，在导管室中进行血管成形术的患者必须与导管原位一起运送到进行近距离放射治疗的放射肿瘤学设施。本项目的目的是证明使用低能量125-碘源治疗外周动脉的血管内近距离放射治疗系统与使用高能量192-铱源的现有系统一样安全有效，并且适用于在导管室内进行外周血管内近距离放射治疗。 这一目标的实现将通过以下方面来证明：a）设计和制造一种适当的高放射性125-碘源，其形式适合于外周血管内治疗的输送，和B）完成评价原型源的安全性和剂量测定有效性的研究。 该项目的主要受益是开发了一种放射源和屏蔽系统，该系统将允许在不移动患者及其附带风险的情况下进行近距离放射治疗，并在手术期间将患者置于心脏病专家的监督下。我们预计，这一发展将扩大外周血管内近距离放射治疗的使用，以更大数量的医院中心。

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.