A Fluorescence-based Optomechanical Sensor for Intraocular Pressure Monitoring

描述（由申请人提供）：眼内压（IOP）监测是有效治疗青光眼和其他眼高相关疾病的重要诊断工具。临床试验表明，频繁的IOP监测可以减缓青光眼的进展，并最大限度地减少视神经损伤。目前的IOP监测技术（如眼压计）无创且操作简单，但不准确，不适合终身频繁的IOP监测：由于测量是由训练有素的人员进行的，因此需要前往医院或诊所。我们提出了一种“基于近红外荧光的光学机械”（NiFO）眼压传感技术，用于对中度或重度青光眼患者进行精确的、基于家庭的眼压监测。NiFO技术基于无电子微机电系统（MEMS）植入式传感器（称为“NiFO传感器”），可将IOP变化转换为近红外（NI）状态下的双波长光信号。NiFO传感器被集成到人工晶状体中，或通过手术附着在虹膜上，从而永久植入患者的眼睛。采用外接便携式光学读出系统（ORS）对NiFO传感器进行激励，采集并分析发射的NI光信号。无电源NiFO传感器允许频繁和终身IOP监测，允许患者在家中进行IOP测量，无需维护（例如更换电池），它是准确的，它具有非常小的尺寸（< 0.5 mm3）和占地面积（~0.25 mm2）。我们的研究计划包括以下目标：1)NiFO压力传感器的微加工和体外测试。由硅/PDMS芯片组成的NiFO传感器将使用标准的体和表面硅微加工工艺进行微加工。其规格（动态范围，精度误差等）将在体外通过将NIFO传感器浸入充满房水的浴液中来确定。2)光学读出系统（ORS）的构建。制造一种便携式光学读出系统，包括光学头和激发/检测单元。该系统将集成激发NiFO传感器所需的所有光学器件，收集分析发射的NI荧光信号。提出的技术将有助于有效地管理和治疗青光眼和高血压相关疾病，并将引发其他可用于各种压力监测生物医学应用的植入式、无电源、小型化设备的发展。

DESCRIPTION (provided by applicant): IntraOcular Pressure (IOP) monitoring is an essential diagnostic tool for the efficient treatment of glaucoma and other ocular hypertension-related diseases. Clinical trials have shown that frequent IOP monitoring can decelerate the progress of glaucoma and minimize optical nerve damage Current IOP monitoring technologies (e.g. tonometry) are non-invasive and simple to execute, but they are not accurate and not suitable for life-long and frequent IOP monitoring: they require a visit to the hospital or to a clinic as the measurement is performed by trained personnel. We propose a 'Near Infrared Fluorescent-based Optomechanical' (NiFO) IOP sensing technology for accurate, home-based, IOP monitoring for patients with moderate or severe glaucoma. The NiFO technology is based on an electronic-free MicroElectroMechanical Systems (MEMS) implantable sensor (termed the 'NiFO sensor') that converts IOP changes into a dual-wavelength optical signal in the near infrared (NI) regime. The NiFO sensor is integrated into an intraocular lens or surgically attached on the iris and therefore permanently implanted into the patient's eye. An external, portable optical readout system (ORS) is used to excite the NiFO sensor, collect and analyze the emitted NI optical signal. The power-free NiFO sensor permits frequent and life-long IOP monitoring, allows the patient to perform the IOP measurement at home, requires no maintenance (e.g. battery replacement), it is accurate and it has a very small size (< 0.5 mm3) and footprint (~0.25 mm2). Our research plan consists of the following aims: 1) Microfabrication and in vitro testing of the NiFO pressure sensor. The NiFO sensor, consisting of a silicon/PDMS chip will be microfabricated using standard bulk and surface silicon micromachining processes. Its specifications (dynamic range, precision error, etc) will be established in vitro by immersing the NIFO sensor into a bath filled with aqueous humor. 2) Construction of the Optical Readout System (ORS). A portable optical readout system consisting of an optical head and an excitation/detection unit will be manufactured. The system will integrate all the optics needed to excite the NiFO sensor, collect analyze the emitted NI fluorescence signal. The proposed technology will help in efficiently managing and treating glaucoma and hypertension-related diseases and it will trigger the development of other implantable, power-free, miniaturized devices that can be used in a variety of pressure monitoring biomedical applications.