The FDA has approved AcuFocus’ KAMRA inlay, the first implantable device to help improve vision in patients with presbyopia who have not had cataract surgery.

The implant is intended for patients ages 45 to 60 who don’t need assistance with distance vision but have trouble seeing close objects or small print and need reading glasses with plus-1.00 to plus-2.50 diopters of power.

The ring-shaped device works by blocking unfocused light rays from entering the eye while allowing central light rays to pass through a small aperture, removing blurriness. Results from clinical trials showed that 83.5 percent of 478 patients had vision clarity of 20/40 or better after one year.

The FDA, which announced the approval April 17, stresses that the implant’s safety is unknown in patients who have had LASIK procedures. Use is contraindicated in patients who have had cataract surgery or have severe dry eye.

The KAMRA inlay is already marketed in Europe and 33 other countries. AcuFocus has set up a global registry to monitor and share clinical outcomes with surgeons and advance the surgical procedure, the company said. — Charlotte Astor