May 18, 2022 16:00:00

'Smart contact lenses' that release drugs according to the condition of the eyes may save people from blindness

'

Glaucoma ' is a disease that can cause blindness because the optic nerve is compressed due to increased intraocular pressure and the visual field is impaired. A Chinese research team has developed a smart contact lens that contains a drug that is effective against glaucoma and senses and releases intraocular pressure.

Intelligent wireless theranostic contact lens for electrical sensing and regulation of intraocular pressure | Nature Communications
https://doi.org/10.1038/s41467-022-29860-x

'Smart' Contact Lens Could Help Treat a Leading Cause of Blindness, Scientists Say
https://www.sciencealert.com/newly-developed-smart-contact-lens-could-treat-the-second-leading-global-cause-of-blindness

Glaucoma is a general term for a group of ophthalmic diseases that cause irreversible vision loss and blindness due to damage to the optic nerve that conveys visual information to the brain, and is said to affect millions of people around the world. There are various reasons for damage to the optic nerve, but it is thought that glaucoma occurs when the intraocular pressure increases and the optic nerve is compressed for some reason. Laser treatment and surgery are performed.

However, since intraocular pressure fluctuates depending on the activity state and the cycle of sleep / wakefulness, regular monitoring is extremely difficult, and the initial symptoms of glaucoma often appear in the peripheral visual field, making it difficult to detect early.

Therefore, contact lenses that are in close contact with the eyes are attracting attention as a treatment for eye diseases such as glaucoma. However, it can be very difficult to incorporate electrical circuits and sensors into small, flexible and very thin contact lenses.

A research team led by Chen Yang of Zhongshan University has succeeded in producing contact lenses with a design like a snowflake by laser cutting, with multiple sensors embedded so as not to irritate the eyes. This lens is designed for the treatment of acute angle-closure glaucoma .

The developed contact lenses are coated with

brimonidine , an anti-glaucoma drug, and sandwich an ultra-thin air film. This air film is hooked on an electric circuit, and when the air film is compressed by the pressure from the eyeball, the change in intraocular pressure is detected. Brimonidine is prescribed to the eyeball from the back of the lens using a technique called iontophoresis .

At the time of writing, this contact lens has only been tested in pig and rabbit eyes, and it seems that it will take a little longer to conduct clinical trials in humans. However, in tests with pig and rabbit eyes, the research team reported that they succeeded in delivering brimonidine into the eyes as planned and rapidly reducing intraocular pressure.

'This smart contact lens method could be a promising treatment for other ophthalmic disorders, and is compatible with the large, cost-effective manufacturing process of computer circuit boards. , It is relatively easier to manufacture than other smart contact lenses. '