As the number of individuals developing glaucoma is increasing, researchers and ophthalmologists are exploring new approaches to monitor intraocular pressure, which is a critical measurement for glaucoma detection. Current monitoring methods, such as implantable pressure sensors and wearable contact lenses with sensors, are being explored in eye research clinics. However, these systems currently lack in providing 24 hours data through a practical platform for large-scale use. This paper presents a novel method that provides constant measurements of the scleral strain, which is correlated with the change of intraocular pressure, using a nanofabricated discrete resistor array implant sensor. A preliminary bench-top test was performed using the sensor, and it showed that the nanofabricated 1.6 mm by 2.7 mm resistor array exhibits discrete sensing levels at increments of 41 ohms as a fixture needle traversed approximately half of the array. Though the nanosensor is in the prototype developing stage, it promises a new modality for constant, remote, and around the clock glaucoma monitoring.

Application of RFID technology to intraocular instrumentation requires an understanding of the reliability of propagation through optical tissues and fluids. In this study, the working distance for passive RFID operation is measured in a simulated intraocular environment using porcine eyes. Results are obtained in three common RFID ranges: low frequency, high frequency and ultra-high frequency. Several media were tested to assess the possible impact of intraocular materials. Variations in the possible working distance were observed for certain media, but the data suggest that reliable RFID operation for intraocular sensors is possible at a range of 2-4 cm.