A soft contact lens with a MEMS strain gage embedded for intraocular pressure monitoring

We propose a novel approach to intraocular pressure (IOP) measurement allowing minimal invasive continuous monitoring over prolonged periods, regardless of patient position and activities. The key element of this innovative measurement method is a soft contact lens with a microfabricated strain gage embedded allowing the measurement of the cornea curvature deformation due to IOP changes. Tests on a eye-simulating device have shown that the sensor is capable of monitoring continuously a deformation of cornea radius inferior to 0.0055 mm, which corresponds to a sensitivity of better than 2 mmHg IOP, according to an in vitro and an in vivo studies about the correlation between IOP and corneal curvature in human beings.