When most people think of contact lenses, they typically associate them with vision correction. In some cases, people may even wear contact lenses without a corrective prescription solely for cosmetic purposes, such as changing their eye color. Smart contact lenses are a new take on traditional contacts in that they are generally not designed for the strict purpose of improving eyesight. By utilizing advanced technology, these lenses are primarily meant for the purpose of monitoring or maintaining eye and general health. Although most smart contacts are not yet on the market, their development may potentially change how certain conditions are controlled and monitored.
Smart Contacts and Glaucoma
Glaucoma is a condition in which internal fluid in the eyes builds up and puts pressure on the optic nerves, which are the nerves that connect the eyes to the brain. When this happens, it can eventually cause irreversible loss of sight. Currently, doctors treat this condition with eye drops and by monitoring the patient’s intraocular pressure (IOP) using an instrument called a Goldmann tonometer. While this is effective to some extent, it is limited in that it only provides a reading at the time of day that the patient has an appointment. Because eye pressure fluctuates throughout the day and night, the measurement taken at the eye appointment only gives the doctor a limited idea of what the patients true IOP range is.
Smart contacts are made to monitor a person’s IOP over a 24 hour period. When the lenses are inserted, a strain gauge that is embedded in the lens measures the curvature of the wearer’s eye. As the eye pressure fluctuates, there will be changes in the curvature. By keeping the lens in for 24 hours, doctors are able to see when the pressure peaks, which provides them with more accurate information to correctly administer medication and provide care. In order to gather data from the contact lenses, the information is transmitted via an induction loop to a receiver worn by the patient. These contact lenses are not meant for daily wear and are instead meant to be used approximately every six months for 24 hours. Glaucoma-monitoring smart contacts have been available in certain areas in Europe since 2010, but have not yet been approved for use in the United States.
Diabetes and Smart Contact Lenses
Another type of smart contact lens that is not yet in use, is a contact meant for the management of diabetes. When a person is diabetic, he must check his glucose levels on a regular basis. Typically this is done using a blood glucose monitor that requires a drop of blood from a finger prick. Smart contact lenses can make pricking the finger for blood unnecessary, as glucose levels are also detectable in a person’s tear film. Glucose is measured by tiny electrodes, or probes, on the contacts. These electrodes transmit the results to a receiving device that is worn by the patient.
Dispensing Eye Medication
Smart contact lenses are also being designed as a dispensing method for eye drops. In eye care, eye drops are crucial in the treatment of many conditions. This can be a problem because often people have difficulty when inserting eye drops. As a result drops are not taken, or they are wasted when they are not put in properly. This can happen because of a fear of eye drops, or because of difficulty handling the small bottles that the drops are dispensed from. Smart contact lenses are being developed to administer eye drops without patient involvement beyond the insertion of the lens. The goal of these contacts is to release medicated drops over a certain period, depending on the type of contact lens used. The idea is that the medication is impregnated on a film that is attached to the contact lens. As the film degrades, the medication is gradually released.
Smart Contact Lenses in the Future
There are many potential ideas and when it comes to the future of smart contacts. In terms of general health care, scientists hope to develop lenses that can accurately measure a person’s cholesterol and even blood alcohol levels. In the treatment of eye conditions, some researchers are developing ways to combine contacts that measure a person’s IOP and also administer the necessary glaucoma drops. Outside of health care, smart contacts with heads up displays are being researched. This type of contact would map images directly in the wearer’s field of vision, without the use of glasses, a monitor or a headset.