Poets say the eyes are a window to the soul. But biomedical engineers are using the eyes to gain insight into the body.
They’re hard at work on futuristic-sounding technology that uses smart contact lenses and implantable lenses to diagnose, monitor, and treat a wide range of diseases. In 2014, two of the largest multinational companies made an announcement that brought this new technology into sharp focus. Google, through its biology offshoot, now named Verily Life Sciences, and the Swiss pharmaceutical giant Novartis International, through its eye care division Alcon, joined forces to design, develop, and commercialize smart contact lenses for diabetics. If the project reaches its goals, these lenses will spare diabetics from the daily finger pricks typically used to measure blood glucose levels, instead employing embedded microelectronics to measure glucose in the wearer’s tears.
Verily and Alcon aren’t the only ones pushing smart-lens technology forward. In labs around the world, biomedical engineers have been making exciting progress on smart lenses to diagnose diseases and allow unobtrusive and continuous monitoring of patients. In fact, two smart-lens products have already hit the market in Europe to help patients with glaucoma, one of the world’s most common eye diseases.
All of the efforts rely on two basic types of smart lenses: contact lenses similar to those used for vision correction and intraocular lenses that must be surgically implanted in the eye. The former are obviously easier to put into position, as they can be slipped into the eye on a fingertip. They also allow for a broader range of physical and biochemical microsensors, because the lenses can be replaced when the sensors wear out. Intraocular lenses, on the other hand, allow for long-term monitoring without the patient having to take any action.
Both types of lenses may benefit from new kinds of flexible electronics that are microscopic or semitransparent. Advances in materials science have also made it possible to fabricate lenses from materials like hydrogels, which can tolerate the physical stress of eye movements while allowing oxygen to pass through and nourish the eye. Although significant technical challenges remain, we’re already beginning to look into people’s eyes—not for emotional revelations but for medical ones.
By Diego Barrettino | IEEE Spectrum
Image Credit: Sensimed