Fusion of Micro-Array Flow Sensor Data for Smart Cerebral Spinal Fluid Drainage Shunts

脑脊液(CSF)分流术是脑积水的长期治疗选择，脑积水是一种与脑内脑脊液积聚相关的先天性疾病。如果不治疗，脑积水会导致发育障碍和死亡。植入型脑脊液分流术自20世纪50年代S以来一直在使用；然而，大约39%的分流术在第一年内失败，53%的分流术在前两年失败，大约80%的分流术在植入后的某个时候失败。这项研究项目的目标是开发一个智能的脑脊液流量传感器，能够报告植入后脑脊液的排出量。提出的解决方案是基于超灵敏磁阻传感器、射频识别技术和超顺磁性微结构制造的进展。这项研究有望显著改善脑积水患者的生活质量，因为即将发生的分流失败可以及早发现，以便在不利的健康或认知影响发生之前进行纠正。研究小组还计划将这项研究整合到本科生和研究生的教育活动中，并基于开发低成本医疗传感器的共同目标，开发一个将商业实践整合到设计过程中的本科生设计计划，以提高设计系统成功应用的可能性。这项提议的科学目标是证明使用巨型磁阻传感器检测非常缓慢的流体，如脑脊液的可行性。最新一代的传感器被称为磁隧道连接设备，将用于检测脑室腹膜分流管腔内纤毛状结构的流动诱导运动。要实现这种非接触测量，需要新的传感器架构，使其不受低频噪声(传感器漂移)、环境磁干扰的抑制，并开发一种允许无线操作的超低功率传感器询问方案。目前的工作将研究MTJ传感器中的低频噪声源，以及重新校准传感器的间接方法，并将开发一种能够以1ml/小时分辨率分辨脑脊液流量的感应供电流量传感器。所获得的知识将不仅适用于脑积水分流，而且更广泛地适用于低流量系统的测量。此外，预计关于磁隧穿结器件本身的知识将会有显著的进步。

Cerebral spinal fluid (CSF) shunting is a long-term treatment option for hydrocephalus, a congenital condition associated with accumulation of cerebral-spinal fluid in the brain. If left untreated, hydrocephalus leads to developmental disabilities and death. Implanted cerebrospinal fluid shunts have been in use since the 1950's; however approximately 39% of shunts fail within the first year, 53% fail within the first two years, and about 80% fail at some point after implantation. The goal of this research project is to develop a "smart" CSF flow sensor, capable of reporting the amount of CSF drained from the brain after implantation. The proposed solution is based on the combined use of ultra-sensitive magnetoresistance sensors, radio-frequency identification technology, and advances in the manufacturing of super paramagnetic micro-structures. This research is expected to significantly improve the quality of life of individuals with hydrocephalus, as pending shunt failure can be detected early to allow correction before adverse health or cognitive effects occur. The research team also plans to integrate this research into undergraduate and graduate educational activities and, based on a common goal of developing low cost medical sensors, develop an undergraduate design program that integrates business practices into the design process to improve the likelihood of successful application of the designed systems.The scientific objective of this proposal is to demonstrate the feasibility of using giant magneto-resistance sensors in the detection of very slow-moving fluids, such as cerebral spinal fluid. The latest generation of these sensors, known as magneto tunneling junction devices, will be used to detect flow-induced motion of a cilia-like structure inside the lumen of a ventriculoperitoneal shunt. Realization of such non-contact measurements requires new sensor architectures immune to low-frequency noise (sensor drift), rejection of ambient magnetic interference, and development of an ultra-low power sensor interrogation scheme allowing for wireless operation. The present effort will investigate the low-frequency noise sources in MTJ sensors, indirect methods for re-calibration of the sensor, and will develop an inductively powered flow sensor capable of resolving CSF flow with 1mL/hr resolution. The knowledge gained will be applicable not only to hydrocephalus shunts, but to measurement of low-flow volume systems more generally. In addition, it is expected that there will be a significant advancement in knowledge regarding magneto tunneling junction devices themselves.