Wavefront-guided excimer laser ablation using photorefractive keratectomy and sub-Bowman's keratomileusis: a contralateral eye study

PURPOSE: To explain the basic science and clinical evidence that has led to the development of a new technique in corneal refractive surgery--sub-Bowman's keratomileusis (SBK). METHODS: A comprehensive review of the literature and report of a contralateral eye study of 50 patients (100 eyes) enrolled at 2 sites (25 patients per site) and randomized according to the dominant eye was conducted. All eyes underwent a wavefront-guided refractive correction using the Alcon LADARVision4000 System. In one eye, an 8.5-mm, ETOH-assisted photorefractive keratectomy (PRK) was performed. In the second eye, an 8.5-mm, 100-microm flap was attempted using a 60 kHz IntraLase FS femtosecond laser. Pre- and postoperative tests included best spectacle-corrected visual acuity, uncorrected visual acuity, corneal topography, wavefront aberrometry, retinal image quality, contrast sensitivity, and biomechanical response of the cornea. Patients completed subjective questionnaires at each follow-up. RESULTS: Clinical results demonstrate that SBK provides quicker visual recovery, although the data suggest that the 3- and 6-months results are similar in terms of visual outcomes. Reichert Ocular Response Analyzer results demonstrate that its impact on the cornea is similar to PRK. CONCLUSIONS: This study indicates that SBK provides the visual recovery of a LASIK procedure with the Optical Response Analyzer results similar to PRK.