Corneal Apical Scar After Hyperopic Excimer Laser Refractive Surgery: Long-term Follow-up of Treatment With Sequential Customized Therapeutic Keratectomy

PURPOSE: To evaluate long-term results of sequential customized therapeutic keratectomy (SCTK) in highly aberrated corneas with apical scars consequent to hyperopic excimer laser refractive surgery. METHODS: Fifteen eyes of 12 patients treated with SCTK for a corneal apical scar after hyperopic excimer laser refractive surgery were retrospectively evaluated. SCTK is a sequence of custom therapeutic excimer laser keratectomies where the results are monitored step-by-step by intraoperative corneal topography. In the pre-operative and postoperative course, corrected distance visual acuity (CDVA), corneal topography and aberrometry, Scheimpflug tomography, and anterior segment optical coherence tomography were compared before and after SCTK. RESULTS: The postoperative follow-up comprised 7 patients with 1 year and 8 patients with more than 2 years of follow-up. Functional results showed a significant increase of CDVA from 0.36 +/- 0.31 to 0.14 +/- 0.25 logMAR at the last available follow-up. Mean sphere did not change significantly from the baseline, demonstrating that SCTK does not induce hyperopic shift. Higher order aberrations decreased significantly from 2.57 +/- 1.92 to 0.80 +/- 0.42 mu m at the last follow-up. Topographic indexes (irregular astigmatism index, surface asymmetry index, and surface regularity index) showed a significant improvement after SCTK. Pachymetry 3 months postoperatively showed no significant reduction during the entire follow-up in either minimum or central thickness. CONCLUSIONS: Long-term results demonstrate that SCTK can treat this sight-threatening complication of hyperopic excimer laser refractive surgery, achieving significant improvements in visual acuity and in many corneal morphological parameters.