An implantable corneal inlay recently approved by the FDA gives ophthalmologists a new choice in treating presbyopia. The inlay (Raindrop Near Vision Inlay, ReVision Optics) increases the prolate shape of the cornea to increase central keratometry by about 4 D while mean keratometry increases by about 1.7 D. These topographic changes translate into a 5-line improvement in near vision without compromising binocular distance vision.
“The [inlay] itself has no refractive power,” said Ralph Chu, MD, Chu Vision Institute, Bloomington, MN, and clinical investigator, ReVision Optics. “It is refractively neutral and improves near vision by altering the prolate shape of the cornea and increasing the central power of the cornea. The change in shape is very gradual and very smooth, which gives the marked improvement in near vision with very little change to distance vision.”
He evaluated visual outcomes and topographic changes in a cohort of 23 patients who were part of a multicenter trial with 373 patients that led to the approval of the device. The inlay has been used clinically in Europe and Asia for several years.
The inlay was approved for implantation in the nondominant eye in patients 41 to 65 years of age who have not had cataract surgery and need near vision correction of +1.50 to +2.50 D, but no distance correction.
The clear, lens-shaped hydrogel device is about 2 mm in diameter and 30 μm thick — about half the diameter of a human hair. The inlay is completely invisible after implantation. It is placed beneath a standard 8 to 9 mm LASIK flap cut to a depth of about 30% of the total corneal thickness.