Biotechnology: Contact lens measures pressure and delivers glaucoma drug

A contact lens capable of wireless intraocular pressure sensing and on-demand anti-glaucoma drug delivery, is reported in Nature Communications. The device is flexible and battery-free, with a compact design, and may be a promising system for the treatment of glaucoma.

Glaucoma (and its associated diseases) can cause irreversible vision loss, with damage often caused by an increase of intraocular pressure due to the abnormal circulation of fluid within the eye. 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. Theranostic devices — which combine therapeutics and diagnostics — are capable of monitoring a determined condition and applying an appropriate treatment.

Xi Xie, Cheng Yang and colleagues developed a theranostic contact lens, which uses electrical sensing to measure intraocular pressure and can deliver a drug on demand. The device was tested in porcine and rabbit eyes and was able to detect changes in intraocular pressure. When the measured intraocular pressure reaches a high-risk level, the drug delivery module (powered by wireless power transfer) has the ability to trigger delivery of an anti-glaucoma drug into the anterior chamber of the eye across corneal barriers.

The authors suggest that fabrication of the device is compatible with existing large-scale and cost-effective manufacturing processes. However, they indicate that further research is needed before it can move towards clinical tests.