Smart wireless contact lens can deliver drugs when needed in glaucoma

China: A wireless contact lens device could be helpful for treating the eye condition glaucoma by monitoring the pressure build-up inside the eye and automatic delivery of drugs when it rises too high, according to a recent study in Nature Communications. 

According to some estimates, globally, about 80 million people are affected by glaucoma. It is caused by insufficient drainage of fluid from the eye, which increases eye pressure and can damage the optic nerve that transmits visual signals to the brain. Drugs that help drain excess fluid from the eye, administered in the form of eye drops are commonly used for its treatment. But many people are not able to stick to their treatment schedule. 

For this purpose, Xi Xie at Sun Yat-Sen University in Guangzhou, China, and his colleagues designed a prototype contact lens device that can sense eye pressure and release glaucoma drugs when needed. 

The lens outer layer has six tiny copper plates arranged in a ring around the pupil that sense eye deformation caused by an increase in eye pressure. An antenna placed near the eye then transmits data to a nearby computer. The Lens' inner layer -- in contact with the cornea region of the eye – is loaded with a pressure-lowering drug called brimonidine that can be released when the lens receives a signal from the computer via the antenna.

Their lenses have been trialed in rabbits without glaucoma. they first showed that the device could monitor eye pressure in the animals and transmit the data wirelessly to an external computer. Then the computer was used for wireless transmission of a signal to the contact lens that triggered the brimonidine release. 

Then by tracking the rabbits, they found that the eye pressure of the animals had decreased by around a third after 30 minutes and by more than 40 percent after 2 hours, on average.

"The realization of this technology for use at point-of-care settings could revolutionize the lives of millions of patients with glaucoma," says Ali Yetisen at Imperial College London. "It [would be] a wonderful addition to the [tools] of the ophthalmologist."

Reference:

Yang, C., Wu, Q., Liu, J. et al. Intelligent wireless theranostic contact lens for electrical sensing and regulation of intraocular pressure. Nat Commun 13, 2556 (2022). https://doi.org/10.1038/s41467-022-29860-x