Improvement in Accommodation and Dynamic Range of Focus After Laser Scleral Microporation: A Potential Treatment for Presbyopia.

Abstract

To examine the ocular changes in accommodation, wavefront aberrations, and dynamic range of focus (DROF) after laser scleral microporation (LSM) for treating presbyopia. Four presbyopic aged cynomolgus macaques (>13 years; n = 8 eyes) were included. All eyes received LSM with erbium: yttrium-aluminum-garnet laser. Spherical equivalent, true accommodation, pseudo-accommodation, wavefront aberrations, and extended range of focus (EROF), or collectively known as DROF, were evaluated using a ray tracing aberrometer. True accommodation referred to the difference in spherical equivalent between distance and near vision, whereas EROF (sum of true and pseudo-accommodation) was determined by measuring the difference in diopters (D) between near and distance through-focus curves, at 50% threshold of the visual Strehl ratio of optical transfer function. From before to seven months after surgery, there was a significant increase in true accommodation from 0.6 ± 1.0 D before surgery to 5.9 ± 2.8 D at seven months after surgery (P < 0.001). EROF increased significantly from 3.4 ± 1.0 D before surgery to 11.1 ± 4.6 D at seven months after surgery (P < 0.001). Ocular aberrations did not vary significantly between preoperative and various postoperative timepoints in either disaccommodated or accommodated states (P > 0.05). No adverse event such as scleral perforation or hypotony was noted. This non-human primate study demonstrated that LSM serves as a novel therapy for improving accommodation and DROF function biomechanically, with a positive response observed throughout the seven-month postoperative period. This proof-of-concept study highlights the potential of LSM as a novel treatment for vision recovery in presbyopic eyes.