A smart contact lens that can detect changes in intraocular pressure in glaucoma patients and even deliver treatment has been developed. Made solely of soft polymer material like conventional soft lenses, with no metal sensors or electronic circuits, it offers excellent comfort and does not obstruct vision. If the efficacy proven in animal studies is confirmed in human clinical trials, the lens is expected to open a new path for glaucoma treatment.
A research team led by Professor Yangzhi Zhu at the Terasaki Institute for Biomedical Innovation in the United States said in the journal Science Translational Medicine on the 8th local time that it "developed a smart contact lens that measures intraocular pressure and automatically releases therapeutics, and confirmed its efficacy and safety in animal studies." The team said the lens uses a simple physical phenomenon in which diagnostic reagents and therapeutics move according to changes in intraocular pressure, eliminating the need for metal sensors, electronic circuits, or batteries found in existing smart contact lenses.
Glaucoma is a disease in which fluid does not drain properly from the eye and accumulates, raising intraocular pressure. It causes severe pain and damage to the optic nerve and, in serious cases, can lead to vision loss. Currently, 70 million people worldwide have glaucoma, and with aging accelerating, the number of patients is expected to reach 134 million by 2040. Although glaucoma is difficult to cure, early diagnosis and treatment can slow vision loss and maintain quality of life. Countries around the world are in fierce competition to commercialize smart contact lenses that track intraocular pressure in real time and automatically release drugs.
◇ Equipped with diagnostic reagents and therapeutic drug reservoirs
The Terasaki Institute, a nonprofit research organization in Los Angeles, developed the contact lens as a medical device for diagnosis and treatment. With checkups every 6 to 12 months as is common now, it is difficult to accurately monitor intraocular pressure in glaucoma patients with large fluctuations. Because the contact lens is worn continuously, it can measure pressure in real time. Above all, the team said this smart contact lens is made only of polymer material like conventional soft lenses, offering the same level of comfort.
The smart contact lens has a structure in which pouches containing diagnostic reagents and therapeutics are embedded between the outer and inner protective layers. When intraocular pressure rises, the cornea expands. The reagent pouch is then compressed and moves along a serpentine microchannel. The distance the reagent travels is proportional to the pressure level. When the patient takes a photo of the eye with a smartphone camera, artificial intelligence (AI) provides an accurate pressure reading.
The pouch has a silk-based sponge structure that holds a large amount of drug while supporting the microchannel to prevent collapse, improving measurement accuracy. As pressure rises, the therapeutic pouch is compressed at the same time. When pressure exceeds a threshold, a pathway opens and a pressure-lowering drug is released. The drug is released automatically without signals from an external device.
Two drugs—timolol and brimonidine—are loaded separately to enable stepwise treatment according to pressure. The researchers fitted the contact lens to the eyes of live rabbits, where it stably tracked pressure and automatically released the drug when the threshold was exceeded. Zhu said, "The technology we developed can be applied directly to soft lenses on the market and could be used to diagnose and treat a range of ophthalmic diseases."
Researchers from China, Hong Kong, the United Kingdom, and Canada participated in the study along with Professor Lee Tae-woo of the Department of Materials Science and Engineering at Seoul National University. Lee said, "What is new is that, unlike existing smart contact lenses, we achieved simultaneous pressure measurement and treatment solely through the lens's own mechanical deformation, without relying on batteries, circuits, wireless modules, or actuators," adding, "Because it is compatible with existing soft lenses, commercialization potential looks high, but further validation is needed for long-term wearing safety, mass-production process optimization, and patient-specific pressure threshold calibration."
◇ Korean glaucoma smart lens set for clinical trials this year
Smart contact lenses for diagnosing eye diseases have been under development since the 2010s. Google in the United States worked with Swiss drugmaker Novartis on a contact lens to measure blood glucose in people with diabetes, and a glaucoma contact lens developed by Swiss company Sensimed received U.S. marketing approval in 2016. That lens measures only pressure changes. Going forward, smart contact lenses that deliver drugs as well as diagnose are expected to be commercialized. Korean corporations are at the forefront.
The Korea Medical Device Development Fund selected and announced the "Top 10 flagship projects for 2025" in February last year. One of them is PHI BIOMED's smart contact lens for glaucoma diagnosis and treatment. PHI BIOMED was founded in 2014 by Professor Han Se-kwang of the Department of Materials Science and Engineering at Pohang University of Science and Technology POSTECH. PHI BIOMED used gold nanowires for glaucoma diagnosis.
When pressure rises, the curvature of the cornea changes minutely, altering the shape of the nanowires and thus their electrical resistance. By measuring this resistance wirelessly, changes in pressure can be detected in real time. When pressure rises, the contact lens delivers timolol, a therapeutic, to the eye.
Han said the gold nanowire sensor outperforms the metal ring sensors used in existing smart contact lenses in both sensitivity and transparency. While the metal rings used in older smart lenses are visible to the naked eye, the nanowire sensor is too small to see, making the lens nearly transparent. Han drew global attention by publishing related research in Nature Communications in 2022. Animal testing has been completed, and human clinical trials will begin this year, with commercialization planned as early as 2027.
◇ Japanese team boosts sensor sensitivity 183-fold
Competition to improve sensor sensitivity in smart contact lenses is also intense. A team led by Professor Takeo Miyake at Waseda University in Japan announced in January that it had developed a smart contact lens with pressure measurement sensitivity 183 times higher than prior studies. As with Han Se-kwang's work, the principle is to wirelessly detect changes in the electrical resistance of a metal sensor when the cornea slightly expands as pressure rises.
The lens sensor and the external reader exchange energy via near-field magnetic resonance. The researchers increased sensitivity using a cutting-edge approach called parity-time (PT) symmetry. The Waseda team designed the loss circuit of the lens sensor and the gain circuit of the reader to mirror each other. By perfectly matching the rhythm of energy exchange—like a person on a swing and someone pushing—they greatly amplified tiny changes.
Thanks to this, even minute changes can be detected immediately, the team said. If a conventional sensor is like nudging a ball perched on a very heavy boulder, a PT-symmetric sensor is like a ball teetering on the tip of a sharp pencil. Even a light breeze knocks it over. In other words, it detects minute pressure changes right away. The Waseda team demonstrated performance by fitting the lens to rabbit eyes.
References
Science Translational Medicine (2026), DOI: https://doi.org/10.1126/scitranslmed.ads9541
npj Flexible Electronics (2026), DOI: https://doi.org/10.1038/s41528-025-00507-3
Nature Communication (2022), DOI: https://doi.org/10.1038/s41467-022-34597-8