A four-zone reverse geometry lens (Boston XO; Polymer Technology Corp., Wilmington, MA) composed of fluorosilicone acrylate with an oxygen permeability (Dk) of 100 × 10−11 (cm2/sec)(mL O2/mL · mm Hg) was used for all subjects. The lens has a base curve (central optical zone) diameter of 6.0 mm, a reverse curve of 0.6-mm width, an alignment curve of 1.0-mm width, and a peripheral curve of 0.4-mm width. Lenses were fitted according to the instructions recommended by the manufacturer. In brief, for the first lens selection, alignment curve was decided based on the flatter keratometry reading, and base curve was determined as target power plus 0.75 D. For a fit to be deemed acceptable, the contact lens had to be well centered vertically and horizontally on the cornea and to move approximately 1 mm on a blink. The overall fluorescein pattern resembled a bull’s eye, with 3 to 5 mm of central touch surrounded by a narrow and deep annulus of tears trapped in the reverse curve area. Lenses that decentered superiorly were considered loose, and those that decentered inferiorly were considered too tight. Lateral decentration was resolved by increasing the lens diameter to 10.6 mm. After confirmation of fine centration, proper movement, and appropriate fluorescein pattern, each patient underwent a 2-hour trial. Subsequently, corneal topography was performed to evaluate the efficacy of correction. If a central flat area appeared and the center was within 0.5 mm of the pupil center on the map, it was considered that an acceptable fit was achieved. Overrefraction was then performed, and the final lens was ordered. After lenses were dispensed, subjects consistently wore their contact lenses overnight. The lens design was modified in the event of poor topographic changes or inadequate improvement of uncorrected visual acuity. Total diameter of these lenses was 10.0 mm in most cases and 10.6 mm in several cases. Subjects were asked to wear their contact lenses at least 7 hours per night. To verify continuing ocular health and to observe any effects of lens wear, slit lamp biomicroscopy, including fluorescein staining, was performed in detail at each visit.