A first-in-human pilot study of a novel electrically-passive metamaterial-inspired resonator-based ocular sensor embedded contact lens monitoring intraocular pressure fluctuations  

Glaucoma is a leading cause of blindness with no cure, but early treatment and effective monitoring can often slow the progression of the disease. Monitoring of glaucoma is based on the measurement of intra-ocular pressure (IOP) that is a physiological parameter related to the mechanical state and parameters of the eye. Conventionally, diagnosing and assessing the progression of glaucoma is based on the method of measuring IOP discretely at clinics. Recent studies have demonstrated the importance of continuously monitoring IOP for 24 h to elucidate the effect of circadian rhythm. In this work, a metamaterial-inspired electrically-passive sensor-embedded contact lens is presented to monitor the IOP fluctuations based on a first-in-human pilot study. The sensor inside the contact lens is an electrically passive, metamaterial-based resonator that can be measured using a wearable antenna patch. The system has been tested with six healthy volunteers during an experiment to induce deliberate IOP changes via water-loading and placing the individuals in supine position using a recliner seat. The initial data compared with tonometer measurements suggest that the system can be used to assess the variation of IOP continuously.