Usually developing slowly over time, many cases of glaucoma are only picked up during routine eye tests, by which time lasting damage may already have been caused, the researchers said.
The new contact lens developed by researchers at the Northumbria University, UK, and Bogazici University in Turkey, can detect changes in eye pressure, which signals possible glaucoma.
Glaucoma occurs when the optic nerve, which connects the eye to the brain, becomes damaged, usually by a build-up of fluid in the front part of the eye, which increases pressure inside the eye-known as intra-ocular pressure (IOP).
The new contact lenses contain micro-sensors that monitor changes in IOP over a period of several hours, sending the data collected wirelessly so it can be analyzed by an ophthalmologist and a diagnosis given, the researchers said.
The research, published in the journal Contact Lens and Anterior Eye, sets out the findings from an initial pilot study of six participants. Having determined that the technology works successfully, the researchers now plan to carry out a further study with a larger group of participants, which will take place over the next year. The lenses will then be made commercially available through their spin-off company GlakoLens, they said.
One of the benefits of using the GlakoLens contact lenses to diagnose glaucoma instead of carrying out a traditional examination is that measurements can be taken more easily over a longer period of time, giving a more accurate diagnosis, according to the researchers.
“Intra-ocular pressure, or IOP, can vary greatly over a 24-hour period, so it is important to monitor the patient either at intervals or ideally continuously for a whole day to get the best insight into the health of their eyes,” said Professor Hamdi Torun, of Northumbria University.
“Traditional methods for measuring IOP involve initially going to a clinic for a single measurement in a day, the result of which can be misleading due to the natural variation of IOP,” Torun said.
The benefit of the contact lenses is that once placed in the eye, the patient can then go about their day as normal while their IOP measurements are recorded and sent to a doctor for analysis once the 24-hour period of testing is complete, the researchers said.
The new system has been tested with six healthy volunteers, during which time they were asked to drink 1.5 litres of water and lie flat to intentionally increase their IOP levels, they said.
The GlakoLens contact lenses use an electrically passive sensor embedded in a disposable soft contact lens and a wearable electronic readout system to collect, store, and process the data-making the lens more comfortable and allowing the patient to go about their day as normal, the researchers added.