Non-invasive wireless monitoring of occlusion in biliary stents using arrays of m

描述（由申请人提供）：支架植入已成为治疗因各种狭窄病变而收缩的血管或导管的标准医疗实践。尽管支架通常缓解狭窄的急性症状，但与所有支架相关的主要并发症是进行性闭塞，其是可变的和不可预测的，并且可导致败血症、梗塞或中风。不幸的是，目前用于监测支架闭塞的方法是不确定的、间接的或侵入性的;并且大多数需要昂贵的住院诊断程序。这些缺点往往导致治疗行动的时机不当：先发制人和不必要的支架置换，或症状后支架置换联合紧急抗菌治疗。本提案的目的是证明无线、无创、集成系统的能力，该系统可从支架内部直接测量通畅性。试验将使用胆道支架进行，胆道支架的性能要求对于其他支架应用（如TIPS、冠状动脉和输尿管支架）非常重要。实现这一目标的研究策略有四个组成部分：（1）进一步开发基于与支架集成的磁致弹性共振传感器的传感系统技术，以及相关的无线传感器询问电子设备;（2）使用植入猪标本中的集成胆道支架对传感系统进行体内测试和验证;（3）开发一种可观察、可控和可重复的体外系统，允许细胞（细菌或内皮细胞）在复制植入情况的环境中在传感器上培养;（4）使用体外系统评估传感器的性能。该研究将在考虑完整系统验证的情况下进行，包括：内窥镜输送;传感器生物相容性;亚慢性信号稳定性;传感器分辨率、全量程范围和可重复性;以及系统准确性、无线范围和可用性。本研究的结果将证明该监测方法适用于遭受不同再狭窄病理的各种支架类型。该系统的重要性能目标包括全尺寸范围，包括完全闭塞的支架，小于1 mm的专利直径的分辨率，以及至少7.5 cm的无线范围。 该系统的成功演示将导致一个廉价的，实时的，门诊程序直接监测支架闭塞。这将有助于医生进行及时的干预，并将消除在支架患者植入后护理过程中不必要的侵入性程序。最终，这将导致更低的成本，更少的并发症和更好的结果。此外，无论具体的支架应用，具有该提议所针对的灵敏度和空间分辨率的无线监测系统可以为临床研究人员提供支架闭塞进展的地图。这将提高重要临床研究的效率，并加深他们所获得的知识。

DESCRIPTION (provided by applicant): The implantation of stents has become standard medical practice for treatment of vessels or ducts constricted due to various stenotic pathologies. Although stents often relieve acute symptoms of a constriction, a major complication associated with all stents is progressive occlusion, which is variable and unpredictable, and can lead to sepsis, infarctions, or strokes. Unfortunately, the current methods for monitoring stent occlusion are inconclusive, indirect, or invasive; and most require expensive, in-patient diagnostic procedures. These shortcomings often lead to mistimed therapeutic actions: a preemptive and unnecessary stent replacement, or a post-symptomatic stent replacement combined with emergency anti-sepsis therapy. The objective of this proposal is to demonstrate the capabilities of a wireless, non-invasive, integrated system, which provides direct measurement of patency from inside a stent. Testing will be conducted using biliary stents, an application whose performance requirements are important for other stent applications such as TIPS, and coronary and ureteral stents. The research strategy to achieve this objective has four components: (1) further develop the technology for a sensing system based on a magnetoelastic resonant sensor integrated with the stent, and the associated wireless sensor interrogation electronics; (2) conduct in vivo testing and validation of the sensing system using integrated biliary stents implanted in porcine specimens; (3) develop an observable, controllable, and repeatable in vitro system that allows cells (either bacterial or endothelial) to culture on the sensors in an environment that replicates the implanted situation; (4) use the in vitro system to evaluate the performance of the sensors. The research will be conducted with full system verification in mind, including: endoscopic delivery; sensor biocompatibility; sub-chronic signal stability; sensor resolution, full scale range, and repeatability; and system accuracy, wireless range, and usability. The results of this research will demonstrate the applicability of the monitoring method to a wide range of stent types subjected to different restenotic pathologies. Important performance targets for the system include a full-scale range that includes a fully occluded stent, a resolution of less than 1 mm of patent diameter, and a wireless range of at least 7.5 cm. Successful demonstration of this system will lead to an inexpensive, real-time, outpatient procedure for directly monitoring stent occlusion. This will aid physicians in performing timely intervention, and will eliminate unnecessary invasive procedures in the course of post-implant care of stent patients. Ultimately, this will result in lower costs, fewer complications, and better outcomes. Further, regardless of the specific stent application, a wireless monitoring system with the sensitivity and spatial resolution targeted by this proposal can provide clinical researchers with a map of the progression of stent occlusion. This will result in an improvement in the efficiency of important clinical studies, and in the depth of knowledge gained by them.