U.S. Food and Drug Administration approved the VisuMax Femtosecond Laser for the small incision lenticule extraction (SMILE) procedure to reduce or eliminate nearsightedness in certain patients 22 years of age or older.
“This approval expands the surgical treatment options available to patients for correcting nearsightedness,” said Malvina Eydelman, M.D., director of Ophthalmic and Ear, Nose and Throat Devices, in FDA’s Center for Devices and Radiological Health.
Nearsightedness, or myopia, is a common vision condition in which close objects are seen clearly, but objects farther away are blurred. It occurs when the eye focuses light in front of the retina. This can be due to the shape of the cornea being too steep and/or the length of the eyeball being too long.
The VisuMax Femtosecond Laser removes a small amount of eye tissue to permanently reshape the cornea. A femtosecond (very fast, short-pulsed) laser makes cuts within the cornea, creating a disc-shaped piece of tissue that is removed by the surgeon through a small incision in the surface of the cornea. This tissue removal causes the shape of the cornea to change, which corrects the nearsightedness.
A clinical study of the safety and effectiveness of the device to correct nearsightedness found the procedure resulted in stable vision correction at six months. Of the 328 participants evaluated at six months, all but one had uncorrected (without glasses or contacts) visual acuity of 20/40 or better, and 88 percent had uncorrected visual acuity of 20/20 or better.
Common complications during surgery included difficulty removing the corneal tissue and loss of suction that keeps the laser aligned with your eye. Common complications after surgery included debris at the site of tissue removal, dry eye, moderate to severe glare and moderate to severe halos.
Not all patients are candidates for SMILE, and individuals should carefully review the patient labeling and discuss their expectations with their eye care professional.
Laser refractive surgery (LASIK and PRK) has been established for 25 years to treat myopia (short-sightedness). Over this time, the technology has been significantly improved to enable safe treatment of myopia up to -15D. Improvements including changing the shape of the lens of corneal tissue removed to better match the natural shape, and increasing the diameter of the applied correction to cover larger pupil sizes, have greatly reduced side-effects such as night vision glare and halos. Similarly, safety has been improved by using a laser (femtosecond laser) to create the corneal flap rather than a blade (known as a microkeratome), meaning that the cornea is reliably left with more than the safe amount of tissue.
In 2006, a new method of laser refractive surgery was introduced, small incision lenticule extraction (SMILE), which provides a minimally invasive keyhole method as it avoids the need to create a flap. In SMILE, a single laser (femtosecond laser) is used to make two curved cuts inside the cornea (without breaching the outside) that separate the lens of tissue that needs removing to focus the vision. This lens of tissue is removed in once piece (rather than evaporated as in LASIK) through a small 2mm wide tunnel to the surface.
SMILE has been used to treat short-sightedness up to -10D for more than 200,000 procedures worldwide and has been shown to achieve similar results to LASIK. However, because no flap is needed, this upper part of the cornea can also contribute strength, meaning that the cornea is stronger after SMILE than after LASIK. It is also expected that the accuracy for higher corrections using SMILE would be better than LASIK because the potential inaccuracies associated with excimer lasers (used in LASIK) are eliminated. This study will investigate the results of SMILE for myopia above -10D.