Toward emmetropia: More advances, more improvements
Refractive, corneal surgery in 2016 saw gains in therapies for keratoconus, presbyopia
Another interesting method is the use of concentric femtosecond laser treatments to achieve multifocality in the cornea. This procedure, INTRACOR (Technolas Perfect Vision GmbH), which is under investigation, is performed intrastromally to reshape the corneal tissue.
A fourth approach uses corneal inlays for presbyopia, which is currently gaining more and more acceptance, and some devices have received FDA approval for presbyopia. These devices have different designs, i.e., an intracorneal aperture, a high index of refraction lenticule in the center of the cornea, and a central lenticule to change the cornea curvature causing multifocality.
The recently approved RainDrop Near Vision Inlay from ReVision Optics received the FDA go-ahead in 2016 and joined the KAMRA inlay (AcuFocus) as another option for patients with presbyopia.
Multifocal IOLs and pseudoaccommodating IOLs are approved and also rapidly gaining acceptance for use during cataract surgery to treat presbyopia. The major issues associated with these are glare and halos. Dr. Azar pointed out that the designs are improving, and he predicts that the popularity will increase when the visual issues are addressed.
“In the future, IOLs will be approved that combine correction of astigmatism and multifocality, that is, astigmatic lenses that are multifocal,” he commented.
Many of these lenses are already approved in Europe.
Accommodating IOLs that change shape in the eye in response to accommodation are not yet approved in the United States. Dr. Azar believes that the Smart Lenses from Alcon Laboratories and Google Verily is the final frontier in this area.
“These lenses can be in the form of a smart contact or IOL with a battery inside the lens, computer chip, means to adjust the lens power, and a sensor to know where the eye is focused,” Dr. Azar said. “At near the lens power increases and at distance the power returns to baseline. Regardless of whether the lens is a contact lens or an IOL, they can provide true accommodation.”
He is optimistic about this technology. The first such contact lens is scheduled for clinical testing soon. Dr. Azar holds multiple patents for this technology. The Smart Lens builds on the technologies developed by Google Verily lens for tear glucose measurements in diabetes.