I-Corps: Sensing device to prevent and control glaucoma

青光眼是一组会损害眼睛视神经并导致失明和失明的疾病。一半患有青光眼的美国人没有意识到自己的情况。这是因为青光眼患者在发生不可修复的损害之前通常不会经历任何症状。增加这一问题的是专业诊断的难度。参加所有推荐的眼睛健康检查的患者将每隔1-2年去看一次眼科医生，届时他们将接受眼压计检查以检查青光眼。眼压计测试只需测量一次眼压，但如果患者在每年的就诊期间眼压波动到低端，青光眼可能仍未被发现。此外，在两次访问之间的长时间间隔期间，可能会发生不可逆转的损害和失明。为视力受损和失明的美国人提供护理服务的成本负担来自政府机构(特别是联邦医疗保险，特别是医疗补助)132亿美元，另外还有来自私营保险公司的13亿美元，以及老年人及其家人的57亿美元自付费用。该项目旨在开发一种解决方案，通过升级目前植入的白内障晶状体，为患青光眼风险较高的患者提供移动和持续监测。监测是通过患者将外部读出单元放置在眼睛附近来执行的。这种对现有产品和程序的简单补充将减少青光眼患者的失明发生率和失明程度，并将降低与青光眼造成的不可逆眼损伤相关的成本。正在开发的产品是一种系统，由眼压传感器和相关的实时报告眼压的阅读器系统组成。该产品实际上是由压力传感器和读取器组成的两个组件系统。这种植入式压力传感器完全由生物兼容材料制成，这种材料形成了一种共振结构，随着眼睛内压力的变化，共振频率也会发生变化。该传感器嵌入或层叠在目前用于白内障手术的假体上。该传感器不含电源或内部电路，因此不易出现故障或过期。此外，眼睛中不会引入任何有害物质。相关读取器通过发射低功率射频(RF)信号来远程询问(Ping)谐振传感器，并监视来自传感器的反射信号。压力的变化会导致阅读器读取不同的响应频率。阅读器系统将频繁跟踪压力变化以提供趋势，并在压力增加到可能永久损害视神经的水平时向患者和/或医生发出警报。其目的是创造一款简单的阅读器，既可以是独立设备，也可以是使用智能手机的附加硬件，或者是可穿戴式健康监测系统的附加子系统。这项提案的范围是完成可批量生产的压力传感器的开发、阅读器原型的开发和系统的稳定性测试，最显著的是确定射频链路的限制、传感器植入的可靠性以及潜在的传感器漂移或校准问题。该产品是使用无源射频传感器和外部读取器远程监测身体状况的许多潜在系统中的第一个。

Glaucoma is a group of diseases that can damage the eye's optic nerve and result in vision loss and blindness. Half of Americans living with glaucoma are unaware of their condition. This is because glaucoma sufferers often do not experience any symptoms until irreparable damage has occurred. Adding to this problem is the difficulty of professional diagnosis. Patients who attend all recommended eye wellness exams will see an ophthalmologist every 1-2 years, at which time they will receive a tonometry exam to check for glaucoma. A tonometry test takes a single measurement of the eye pressure, but glaucoma may remain undetected if the patient's pressure happened to fluctuate to the low end during the annual visit. In addition, irreversible damage and blindness could occur during the long time span between visits. The cost burden associated with nursing care for visually impaired and blind Americans amounts to $13.2 billion from government agencies (Medicare, Medicaid specifically), as well as an additional $1.3 billion from private insurance companies, and $5.7 billion in out-of-pocket expenses for seniors and their families. This project aims to develop a solution that offers mobile and continuous monitoring for patients at higher risk of developing glaucoma by upgrading currently implanted lenses for cataracts. Monitoring is performed by the patient placing an external readout unit in proximity to the eye. This simple add-on to an existing product and procedure will reduce the incidence and extent of blindness in glaucoma patients, and will decrease the costs associated with irreversible eye damage caused by glaucoma.The product being developed is a system that is comprised of an intraocular pressure sensor and an associated reader system that reports intraocular pressure in real-time. The product is really a two-component system formed of the pressure sensor and reader. The implantable pressure sensor is solely fabricated of biocompatible materials that form a resonating structure that changes in resonant frequency as the pressure in the eye varies. The sensor is embedded or laminated on current prosthetic lenses used in cataract surgeries. The sensor contains no power supply or internal circuit, hence it does not easily fail or get out of date. In addition, no hazardous materials are introduced in the eye. The associated reader remotely interrogates (pings) the resonant sensors by emitting a low power radio frequency (RF) signal and monitors the reflected signal from the sensor. Changes in pressure will cause the reader to read different response frequencies. The reader system will track pressure variation frequently to provide trends and will alert the patient and/or physician if the pressure increases to levels that can permanently damage the optic nerve. The intent is to create a simple reader that can be a standalone device, an add-on piece of hardware using smart phones, or a sub-system addition to wearable health monitoring systems. The scope of this proposal is to complete the development of mass producible pressure sensors, development of a reader prototype, and robustness testing of the system, most notably identifying limitations on the RF link, sensor implant reliability, and potential sensor drift or calibration issues. This product is the first of many potential systems for remotely monitoring conditions in the body using the passive RF sensors and with external readers.