5. Methodology At the Navy Refractive Surgery Center San Diego (NRSC SD), a total of 300 patients will be enrolled and randomly assigned to three cohorts. PRK will be performed in a standard fashion for all treatment groups. In the first two groups, intraoperative MMC 0.01% for a contact time of 15 seconds will be utilized. During the postoperative period, the first cohort will use the short steroid taper and the second cohort will use the rapid steroid taper. The third cohort will not receive any intraoperative MMC and will self-administer postoperative steroids, tapering for two months. All cohorts will be followed at 1 week, 1 month, 3 months, 6 months and 12 months after the procedure. Standard clinical measures of visual performance will be recorded. Since visually significant corneal haze is relatively rare, corneal densitometry will be used as an objective measure to detect subclinical corneal haze in addition to our usual subjective haze evaluation done by the clinical optometrists.