Purpose: To examine the ocular changes in accommodation, wavefront aberrations, and dynamic range of focus (DROF) after laser scleral microporation (LSM) for treating presbyopia.
Methods: 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.
Results: 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.
Conclusions: 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.
Translational relevance: This proof-of-concept study highlights the potential of LSM as a novel treatment for vision recovery in presbyopic eyes.