Glaucoma, a condition that damages the optic nerve due to fluid build-up in the eye, affects approximately 70 million people worldwide. Often, glaucoma is only detected during routine eye tests, by which time irreversible damage may have already occurred.
In a recent development, researchers have created contact lenses equipped with micro-sensors that can monitor changes in intra-ocular pressure (IOP) over several hours. The collected data is then wirelessly transmitted for analysis by an ophthalmologist. The study, conducted by Professor Hamdi Torun from Northumbria University, and Professors Günhan Dündar and Arda D. Yalcinkaya from Boğaziçi University in Istanbul, involved six participants and was published in the journal Contact Lens and Anterior Eye.
Having confirmed the effectiveness of the technology, the researchers plan to conduct a larger study over the next year. Following successful completion of this study, the lenses will be made commercially available through their spin-off company, GlakoLens. One advantage of using these contact lenses is that they allow for easier and more accurate measurements of IOP over an extended period of time.
Professor Torun explained that IOP can vary significantly throughout a 24-hour period, making continuous monitoring crucial for accurate diagnosis. Traditional methods involve single measurements taken at clinics, which can be misleading due to natural IOP variations. If irregularities are detected, further investigation requires hospitalization and repeated measurements using a technique called Goldmann applanation tonometry. This method involves numbing the eye with drops and using a small cone to touch the cornea for pressure measurement. However, studies have shown that waking patients up at night for measurements can lead to less accurate results and discomfort.
The newly developed contact lenses allow patients to go about their daily activities while their IOP measurements are recorded and sent to a doctor for analysis once the 24-hour testing period is complete. The system has been tested on six healthy volunteers who were asked to increase their IOP levels by drinking 1.5 liters of water and lying flat.
Unlike previous products that use an electrically active silicon chip, resulting in thicker and less comfortable lenses, the GlakoLens contact lenses utilize an electrically passive sensor embedded in a disposable soft lens. The data is collected, stored, and processed using a wearable electronic readout system. In addition to diagnosing glaucoma, the researchers believe these lenses have the potential to detect other health conditions by measuring molecules such as glucose and lactic acid in the eye.