GUANGZHOU, China — A smart contact lens could end the misery of eye drops for glaucoma patients. Researchers in China say the device measures pressure in the organs – delivering drugs directly on demand.
“The device is flexible, wireless and battery-free,” project leader Professor Xi Xie of Sun Yat-Sen University in Guangzhou, China says, according to a statement by SWNS. “It has a unique, compact cantilever design, and is minimally invasive – making it highly promising for the treatment of glaucoma.”
Glaucoma is the world’s leading cause of blindness. It is triggered by intraocular pressure inside the eye, which damages cells in the optic nerve.
“This pressure can vary with human activities and circadian rhythm, which makes treatment challenging, as it requires the long term and continuous tracking of the eye’s condition,” Prof. Xie explains.
Daily prescription drops are awkward to use, mixing with tears, and running down the face instead of going into the eye. The lens, called a “theranostic”, is a potential gamechanger. It slowly applies the appropriate dose by combining therapeutics and diagnostics.
“Electrical sensing measures intraocular pressure. A drug is then delivered on demand through the curved and limited surface of the lens,” researchers tell SWNS.
Scientists could also add antibiotics, making wearers less vulnerable to bacterial infections than they are with normal lenses. In experiments, the device detected changes in pigs and rabbits, which have similar eyes to humans.
“The drug delivery module has an efficient circuit that provides electrical power without the need of wires,” Prof. Xie says. “When the intraocular pressure reaches a high-risk level, it has the ability to trigger an anti-glaucoma drug into the anterior chamber of the eye across corneal barriers.”
Standard medications often miss the eyes
According to the CDC, over three million Americans have glaucoma. Estimates project that number to rise to over six million by 2050.
The eyeball contains a fluid called aqueous humor which is constantly produced, with any excess drained though tubes. Glaucoma develops when the fluid cannot drain properly, and the intraocular pressure builds up. Studies show one in two patients stop taking eye drops after a year due to forgetfulness or physical limitations like arthritis — leaving them vulnerable to vision loss.
Another problem is about 95 percent of the medication ends up in places where it doesn’t help the eyes — draining into the nasal cavity. If these drugs get into the bloodstream and travel to other organs, they can cause serious side-effects.
Drugs in a contact lens would release slowly enough to stay in the eye, according to the researchers.
“Fabrication of the device is compatible with existing large-scale and cost-effective manufacturing processes,” study authors tell SWNS.
“Engineering wearable devices that can wirelessly track intraocular pressure and offer feedback-medicine administrations are highly desirable for glaucoma treatments,” the team writes in the journal Nature Communications.
Scientists are hopeful that clinical trials will begin after they complete further safety tests.
South West News Service writer Mark Waghorn contributed to this report.