Changes in Keratometric Values and Higher-Order Aberrations in Hydrogel Corneal Inlay Implantation
The purpose of this study is analyzing surgically induced refractive change (SIRC) and the change of the high-order aberration after Raindrop corneal inlay insertion and finding the principle that Raindrop corrects presbyopia.
The Raindrop corneal inlay (ReVision Optics, Inc.) was implanted on the corneal stromal bed beneath a keratotomy flap in 11 nondominant eyes of 11 patients. Simulated K, true net power (TNP), equivalent K-reading (EKR) were provided by Pentacam (Oculus) Scheimpflug rotating camera and the change of keratometric values were compared with surgically induced refractive change (SIRC) measured by subjective refraction. Corneal high-order aberrations were also measured.
The change of spherical equivalent refraction was a 1.03 diopter(D) myopic shift. The changes of TNP and EKR at central cornea (3 mm) produced more dioptric power than SIRC. (1.61D, p<0.01 / 2.17D, p<0.01) The EKR changes at 4.5 mm zone and 5.0 mm zone did not produce statistically significant difference with SIRC. (1.22 D,p=0.05 / 1.01 D,p=0.73) Only spherical aberration showed statistically significant difference in analysis in changes of high-order aberrations and the amount of SA change was -0.43 ± 0.12 microns.
Both the keratometry in the peripheral cornea and the refractive spherical equivalent show a myopic refractive shift in response to the inlay effect. The Raindrop corneal inlay corrects presbyopia via increasing negative spherical aberration.