Innovation:

We have developed a smart contact lens capable of continuously measuring intraocular pressure (IOP) over 24 hours. Technological breakthrough towards this capability is a metamaterial-based sensor that offers unprecedented advantages for wireless strain sensing as it is electrically passive, ultra-sensitive, low-cost and can be fabricated and integrated into contact lenses using simple and cost-effective processing steps. Our sensor is based on the principle of resonant frequency shift of a metallic resonator with metamaterial properties under mechanical stress. This is a novel approach to accurately monitor IOP by measuring changes in the geometry of a sensor placed on the cornea. The electrically passive sensor embedded into a contact lens is operated without any battery or power requirements. The data are collected wirelessly by transmitting a very low power radio frequency (RF) signal generated by a lightweight Holter-monitor-like device comprising an electronic circuit and a custom design wearable antenna.

Feasibility/Manufacturability:

We have demonstrated the operation of the full system in a clinical pilot study, published in Contact Lens and Anterior Eye (https://doi.org/10.1016/j.clae.2023.102102). The sensor has been designed and tested for scalability and low manufacturing costs. The sensor manufacturing currently uses standard and highly scalable screen printing and/or photolithography methods where thousands of sensors can be manufactured simultaneously. Then, the sensors are embedded into contact lenses using conventional moulding processes that can be automated easily. The readout electronics is based on off-the-shelf components and can be manufactured using standard PCB processes. Overall, the system can be manufactured cost-effectively at scale.

Marketability:

Glaucoma has become the second leading cause of preventable blindness after cataracts. Currently, over 70M are affected by this disease worldwide, of which 12M are in the EU. This number is likely to increase to 112M individuals by 2040. The current medical practice for the management of glaucoma is to assess IOP during a clinic’s visit. Due to the circadian cycle of IOP, shorter timescale variations and measurement imprecision, the ‘snapshot’ measurement in clinic does not sufficiently characterise the ‘IOP insult’ to an eye. An ideal IOP measurement strategy is to observe the circadian cycles of IOP variation in a period of 24 hours spanning a single day and repeating this measurement strategy periodically over an extended period of time to more precisely estimate the ‘IOP insult’ to the eye. Our invention offers a revolutionary measurement capabilities to address this unmet clinical need.

The global ophthalmic devices market, expected to reach €63 billion by 2027, will grow at a CAGR of 4.2% during the forecast period (2020-2027). Within the global market, the EU ophthalmic devices market segment was valued at €9.2 billion in 2020, and it is expected to reach > €12.2 billion by 2025. Within this market, we target the diagnostic equipment share, accounting for ~20% of the total EU market (€2.5 billion by 2025). Our invention has the potential to disrupt and contribute to the growth of the market, offering the first non-invasive, cost-effective device for glaucoma continuous monitoring.