Benjamin Franklin is credited with developing bifocal glasses in 1760. Of course, one wonders if he wore them while he flew his kite on that dark and stormy night or if he ever had trouble finding them when he wanted to read a book or write a letter!
Most people are smart enough not to fly kites during thunderstorms, yet most people who are over 40 and use reading glasses often lose track of them. Wouldn’t it be nice if there was an alternative to reading glasses other than contact lenses?
Well, there is such an alternative. It is called a corneal inlay. It is a device no bigger than a pencil’s eraser that is implanted in one eye. During surgery, a laser is used to cut a flap in the middle of the cornea and the inlay is inserted into the flap. The inlay improves vision by increasing the depth of focus of the center of the cornea.
There are two types of corneal inlays that are approved by the Food and Drug Administration (FDA):
Small Aperture Inlays
This works like the aperture of a camera by changing how much light is allowed into the eye. The device itself is a doughnut shaped ring, with an opening in the center. The opening focuses light into the eye and narrows the field of vision. This improves sight at close range. This inlay was approved in 2015 for use in the U.S. It takes up to a month for a person to realize the full effect of the inlay. An ophthalmologist who performs the procedure to insert the inlay, Andrew Holzman, MD of TLC Laser Eye Center in Rockville, Maryland states, “We tell the patient to go home, take a nap and then they start using their eye drops,” Holzman said of the recovery process. “And the nicest part about it, if the patient doesn’t like it, it is a reversible procedure.”
Corneal Reshaping Inlays
This procedure reshapes the cornea in order to improve vision. The implant is a small clear disk (primarily made of water). It is inserted closer to the cornea than the small aperture inlay procedure. When the disk is implanted, it makes the center of the cornea steeper. Light that travels through the thinner part of the inlay allows distant items to be seen clearly, while items that are closer to the person can be seen clearly through the central, curved part of the cornea. This too, is reversible.
Of course, after the surgery, patients should use antibiotic and steroid eye drops for a month to prevent infection. Patients who have this procedure may experience problems with glare, halos, and trouble seeing at night. Other problems can occur, such as corneal scarring, swelling, inflammation, thinning, or clouding of the cornea.
Corneal inlays: something to consider the next time you are looking for your reading glasses!