Photorefractive keratectomy followed by same-day corneal collagen crosslinking after intrastromal corneal ring segment implantation for pellucid marginal degeneration

A 28-year-old man with progressive pellucid marginal degeneration (PMD) had photorefractive keratectomy (PRK) followed by same-day corneal collagen crosslinking (CXL) for progressive PMD 12 months after intrastromal corneal ring segment implantation (Intacs). No intraoperative or early postoperative complications occurred. Nine months postoperatively, the uncorrected distance visual acuity improved from finger counting to 20/63 and the corrected distance visual acuity improved from 20/40 to 20/25. Corneal topography revealed a significant improvement in keratometry (from 46.73/38.67 to 44.92/39.01), which remained stable during the 9-month follow-up period. Despite the encouraging results, longer follow-up is necessary to evaluate the outcomes of this approach.