Researchers from Northumbria University in the UK and Boğaziçi University in Turkey have developed contact lenses with embedded sensors that can measure the pressure inside the eye. The information gathered by these lenses is sent to an ophthalmologist for evaluation, with the hope that they can lead to early diagnosis of glaucoma, a condition that can cause irreversible vision loss if left untreated.
Glaucoma occurs when the optic nerve, which connects the eye to the brain, is damaged due to increased intraocular pressure (IOP). This pressure is usually caused by a build-up of fluid in the front part of the eye. The problem with glaucoma is that it develops slowly over time, causing irreparable harm before any vision loss occurs. By the time it is detected during routine eye tests, the damage may already be done.
However, the collaboration between researchers from Northumbria University and Boğaziçi University may change this. They have developed contact lenses that can detect fluctuations in IOP and use this information to diagnose glaucoma. These lenses have been trialed in people.
The contact lenses, known as GlakoLens, have an electrically passive sensor embedded in a disposable soft contact lens made of polydimethylsiloxane (PDMS). The data collected by the lenses is wirelessly transmitted to a wearable electronic readout system, which then processes and stores the information. The processed data is later evaluated by an ophthalmologist.
One of the advantages of using GlakoLens is that it allows for easier and more accurate IOP measurements compared to conventional eye exams. IOP can vary greatly over a 24-hour period, so continuous monitoring is crucial for a better understanding of eye health. Traditional methods involve single measurements at a clinic, which can be misleading due to natural variations in IOP. Further investigation often requires hospitalization for repeated measurements using a technique called Goldmann applanation tonometry (GAT), which can be invasive and time-consuming.
With GlakoLens, once the contact lens is placed in the eye, the patient can go about their day as usual while their IOP measurements are recorded. After a 24-hour testing period, the data is sent to a doctor for analysis.
The researchers conducted tests on six healthy volunteers who intentionally increased their IOP by drinking water and lying flat. The contact lenses accurately responded to the effects of water loading, and the measurements from the lens-wearing eye matched those taken by the device in the lens-less eye.
Further experiments will be conducted with larger groups of healthy individuals to assess the accuracy and reliability of the contact lens sensors. The researchers also plan to optimize the comfort and non-invasiveness of the lenses in future iterations.
It’s worth noting that GlakoLens is not the first glaucoma-detecting contact lens to be developed. In previous studies, researchers from South Korea’s Pohang University of Science and Technology (POSTECH) tested a contact lens that monitored glaucoma and released medication to reduce IOP. Another California-based startup trialed miLens, a ring placed in the eye that physically measured IOP. However, the researchers behind GlakoLens believe their technology offers greater comfort and flexibility.
In addition to diagnosing glaucoma, the researchers believe their lenses could be used to detect other health conditions by measuring molecules such as glucose and lactic acid present in the eye.
The study was published in the journal Contact Lens and Anterior Eye, and the lenses are expected to be commercially available through the spin-off company GlakoLens.
Source: Northumbria University