Non Invasive Sensor for Continuous Intraocular Pressure Monitoring

Pathological elevated intraocular pressure (IOP) is a primary index for glaucoma.In this paper, we present a biocompatible IOP sensor that operates based on the principle of inductorcapacitor (LC) resonance.The IOP sensor is composed solely of a spiral inductor that can sense deformations of corneal curvature.The inductor is fabricated by embedding gold coils into polydimethylsiloxane (PDMS), a soft, biologically compatible material, via MEMS technology.The resonant frequency of the sensor is designed to vary when the IOP is changed in experiments.The frequency response of the sensor is tested using a model eye, a tube, and a network analyzer.The results show that there is approximately linearity between the frequency response of the sensor and the IOP.The sensitivity of the sensor is 417.29 kHz/mmHg, when the pressure ranges from 7.5 to 36.88 mmHg.Consequently, an unstable IOP could be accurately tracked, using the calibrated relationship between frequency response and the IOP.