Initial Evaluation of Photorefractive Keratectomy in U.S. Army Personnel

Inclusion Criteria: * Informed consent. * Normal, healthy active adults with access to medical care at Walter Reed Health Care System. * Age 21 years or older. * Spherical equivalent of the manifest refractive error between -1.0 to -6.0 diopters (D), inclusive, with no more than 3.0D of cylinder. The absolute value of the cylinder (expressed in minus cylinder) will be limited such that the short axis of the elliptical ablation will be no smaller than 4.9mm. The following specifies the maximum cylinder for a given spherical component of the manifest refraction: Spherical component / Maximum cylinder * 1.0D / -0.5D * 2.0D / -1.0D * 3.0D / -1.5D * 4.0D / -2.0D * 5.0D / -2.5D * 6.0D / -3.0D * Corrected vision of at least 20/20 * Soft contact lens users must havE removed their lenses at least two weeks prior to baseline measurements. * Hard contact lens users (PMMA or rigid gas permeable lenses) must have removed their lenses at least four weeks prior to baseline measurements. At least two weekly manifest refractions and keratometry measurements will be required in this interval. The last two measurements must not vary by more than 0.50D in any meridian. * Patients undergoing orthokeratology must have their lenses removed at least 6 months prior to the baseline examination. At least two monthly manifest refractions and keratometry measurements taken after the third month out of lenses must not vary by more than 0.50D in any meridian. * Refractive stability must be documented by…