New Treatment Algorithm to Reduce Spherical Aberration After LASIK Correction for Myopia

A Prospective Study to Evaluate the Feasibility of a New Treatment Algorithm for Wavefront-Guided Lasik Correction of Myopic Refractive Errors

The purpose of this clinical trial is to demonstrate that treatments generated by an investigational algorithm reduces spherical aberration compared to currently available iDesign treatments.

Post-LASIK induction of spherical aberration is currently among the most prominent challenges for refractive surgery. The presence of significant spherical aberration in the visual system results in reduced contrast sensitivity, visual symptoms such as "glare" and "halos," and "night myopia" or the induction of myopia under low lighting (larger pupil size). A modified Treatment Planning Software (TPS) "VSS-Rx1 OPM software" has been developed that uses a modified algorithm (software that designs the LASIK treatment profile) to limit the induction of postoperative spherical aberration. Commercially available software used to calculate the LASIK treatment profile was used in one eye (active comparator [i.e., control]) and VSS-Rx1 OPM software was used in the fellow eye (experimental). Subjects were masked to the use of either the commercially available or VSS-Rx1 OPM software.

Commercially available iDesign treatment planning software used to calculate the LASIK treatment profile in one eye (active comparator [i.e., control]) and investigational software (includes a modified algorithm designed to reduce the induction of postoperative spherical aberration) in the fellow eye (experimental).

Commercially available iDesign treatment planning software used to calculate the LASIK treatment profile vs VSS-Rx1 OPM (includes a modified algorithm designed to reduce the induction of postoperative spherical aberration).

Primary Efficacy Outcome Measure: mean spherical aberration of eyes treated with the VSS-Rx1 OPM treatment planning software compared to that of eyes treated with the commercial iDesign treatment planning software.

Primary Safety Outcome Measure: percentage of eyes losing more than 2 lines of best-corrected distance visual acuity

Inclusion Criteria: Male or female at least 18 years of age at the time of preoperative exam Best Spectacle Corrected Visual Acuity (BSCVA) of 20/20 or better Demonstration of refractive stability Anticipated postoperative stromal bed thickness of at least 250 microns Willing and able to return for all study examinations Exclusion Criteria: Pregnant, breast-feeding, or intend to become pregnant over the course of the study Concurrent use of topical or systemic medications that may impair healing History of prior intraocular or corneal surgery, active ophthalmic disease, or other ocular abnormality Evidence of keratoconus, corneal irregularity, or abnormal topography in the operative eye(s) Known sensitivity or inappropriate responsiveness to any of the medications used in the postoperative course