Clinical and Functional Results of a Combined Surgical Treatment of Pellucid Marginal Degeneration

Abstract

Purpose: To evaluate the clinical results of a combined approach to the treatment of pellucid marginal degeneration, that includes femtolaser-assisted keratotomy, intrastromal lamellar keratoplasty with a use of refractive lenticule and a simultaneous intracorneal ring segment implantation, followed by a local collagen cross-linking.Patients and methods. An analysis of the outcomes of the surgical treatment performed in 20 eyes of 15 patients from 36 to 57 years old who were diagnosed with pellucid marginal degeneration in both of their eyes. During the first stage of the treatment patients underwent a femtolaser-assisted keratotomy in a steep meridian, intrastromal lamellar keratoplasty in the zone of corneal thinning and a simultaneous implantation of intracorneal ring segments with an arc-length of 80 to 160 degrees, followed by a local corneal cross-linking during the second stage. Refractive lenticules obtained during the ReLEx® SMILE procedure were used as a lamellar graft.Results. By the end of the follow-up period of 12 months the UCVA had improved from 0.1 ± 0.07 to 0.33 ± 0.23 and the BCVA from 0.4 ± 0.25 to 0.7 ± 0.28 (p < 0.05). The corneal topography demonstrated a decrease in maximum simulated keratometry values from 49.28 ± 2.57 D to 46.15 ± 1.73 D and an astigmatism reduction from 7.4 ± 3,9 D to 2.1 ± 0,53 D. The corneal thickness increased from 508.0 ± 31.0 μm to 606.0 ± 36.0 μm in the zone of the thinning.Conclusions. The analysis of the clinical outcomes has demonstrated the high efficacy of the combined approach to the treatment of pellucid marginal degeneration. The ICRS implantation allowed for a significant cylinder reduction and an improvement of visual acuity. The lamellar keratoplasty allowed for a reinforcement of the thinned cornea, and the subsequent local collagen cross-linking ensured corneal stability.