Toward Self-Clearing Ventricular Catheter for Hydrocephalus Application

描述(申请人提供)：脑积水患者最常见的治疗方法是手术植入脑脊液分流术。不幸的是，这种对降低颅内压至关重要的设备有相当高的故障率。失败的一个主要原因是脑室导管的阻塞。基于我们对脑室导管阻塞的研究和我们在磁性MEMS方面的经验，我们寻求通过集成磁性微执行器来实现自我清除的脑室导管，该微执行器能够机械地维持清晰的脑室导管，而不需要在分流管中植入电源。我们建议的工作将主要集中在预防和/或逆转近端脑室导管阻塞上。在大多数情况下，导管被堵塞是由于黏附在导管表面蛋白质上的炎性细胞的聚集。该项目的目标是通过使用微电子机械系统(MEMS)技术设计一种能够抵抗细胞积聚导致的闭塞的脑室导管。我们之前已经演示了MEMS磁性微执行器在生物流体中的操作，而不需要直接连线的电源或控制电子设备。我们还设计并测试了一种体外循环细胞培养装置来模拟细胞闭塞过程。使用我们的体外系统，我们寻求评估我们的MEMS设备在预防和消除细胞堵塞方面的性能。我们的具体目标如下：(1)确定使用传统导管、微孔、非致动装置和完全致动装置的闭塞率；(2)确定维持通过毛孔的血流的最佳激活参数(即角度偏转、激活频率和激活持续时间)；以及(3)将我们的磁性微执行器集成到商用脑室导管中，并测试其清除毛孔的效率。这项研究的成功完成将带来一种先进的医疗设备，通过减少分流阻塞的可能性来改善脑积水患者的生活。此外，我们的远程激活自动清除设备技术可以很容易地转化为其他医疗应用，在这些应用中，管腔或毛孔的阻塞是并发症的来源(即其他长期导管、动脉、静脉)。

DESCRIPTION (provided by applicant): The most common treatment for patients with hydrocephalus is the surgical implantation of a cerebrospinal-fluid (CSF) shunt. Unfortunately, this device, which is critical for lowering intracranial pressure, has a substantial failure rate. A leading cause of failure is the obstruction of the ventricular catheter. Building upon our investigation of ventricular-catheter obstruction and our experience with magnetic MEMS, we seek to realize a self-clearing ventricular catheter through the integration of magnetic microactuators that are capable of mechanically maintaining a clear ventricular catheter without requiring an implanted power supply into the shunt. The work we propose will focus primarily on preventing and/or reversing proximal ventricular-catheter obstruction. In most cases, catheters become obstructed due to the accumulation of inflammatory cells that adhere to the proteins on the surface of the catheter. The goal of this project is to design a ventricular catheter that will resist occlusion due to cellular accumulation through the use of micro-electro-mechanical systems (MEMS) technologies. We previously have demonstrated the operation of MEMS magnetic microactuators in biological fluids without the need for a directly wired power supply or control electronics. We have also designed and tested an in vitro circulating-cell-culture setup to model cellular occlusion process. Using our in vitro system, we seek to evaluate the performance of our MEMS devices in preventing and removing cellular occlusion. Our specific aims are as follows: (1) to determine the rate of occlusion using conventional catheter, microfabricated pores, non-actuated devices, and fully-actuated devices; (2) to determine the optimal parameters of activation (i.e., angular deflection, frequency of activation, and activation duration) for maintaining flow through pores; and (3) to integrate our magnetic microactuators into a commercial ventricular catheter and to test their pore-clearing efficiency. The successful completion of this research will result in an advanced medical device that will improve the lives of hydrocephalic patients by decreasing the probability of shunt obstruction. Moreover, our remote activated self-clearing device technology may easily be translated into other medical applications where obstruction in the lumen or pore is a source of complication (i.e., other long-term catheters, arteries, veins).