A Fluorescence-based Optomechanical Sensor for Intraocular Pressure Monitoring

描述(申请人提供)：眼压(IOP)监测是有效治疗青光眼和其他高眼压相关疾病的基本诊断工具。临床试验表明，频繁的眼压监测可以减缓青光眼的进展，将视神经损害降至最低。目前的眼压监测技术(如眼压计)是非侵入性的，操作简单，但它们不准确，不适合终身频繁的眼压监测：它们需要去医院或诊所，因为测量是由训练有素的人员进行的。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、重度青光眼患者进行准确的家庭眼压监测。NiFO技术基于一种无电子的微型机电系统(MEMS)植入式传感器(称为“NiFO传感器”)，可在近红外(NI)区域将眼压变化转换为双波长光学信号。NiFO传感器被集成到人工晶状体中或通过手术固定在虹膜上，因此永久植入患者的眼睛。使用外部便携式光学读出系统(ORS)来激励NiFO传感器，采集和分析发射的NI光信号。无电源的NiFO传感器允许频繁和终身的眼压监测，允许患者在家中进行眼压测量，无需维护(例如更换电池)，它准确，并且体积非常小(&lt；0.5mm3)和占地面积(~0.25mm2)。我们的研究包括以下几个方面：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硅和表面硅微机械加工工艺进行微制造。它的规格(动态范围、精度误差等)将在体外通过将NIFO传感器浸入充满水的浴缸中来建立。2)光学读出系统(ORS)的建设。将制造一种由光学头和激励/检测单元组成的便携式光学读出系统。该系统将集成激发NiFO传感器所需的所有光学元件，采集和分析发射的NiI荧光信号。这项拟议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，并将推动可用于各种压力监测生物医学应用的其他植入式、无电源、微型设备的开发。 公共卫生相关性：眼压(IOP)监测是评估慢性青光眼患者病理状态的重要诊断工具。这项工作旨在开发一种新型的医疗点，植入式眼压监测传感器，将为此类患者提供更好的管理和有效的治疗。

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. PUBLIC HEALTH RELEVANCE: Intraocular pressure (IOP) monitoring is an important diagnostic tool for accessing the pathological condition of patients with chronic glaucoma. This work aims to develop a new class of point-of-care, implantable IOP monitoring sensors that will provide better management and efficient treatment for such patients.