Long-term study of topographic changes following pulsed accelerated corneal collagen cross-linking in progressive keratoconus

Purpose To evaluate long-term stability following pulsed accelerated cross-linking (CXL) in patients with progressive keratoconus by studying the changes in corneal topography. Patients and methods A retrospective study was conducted on patients with progressive grades 1–3 keratoconus who underwent epithelium-off pulsed-light accelerated corneal CXL (30 mW/cm2 for 8 min) using the KXL system (Avedro Inc.). Follow-up period was 12–36 months. Topographic changes including maximum keratometry (Kmax), minimum keratometry (Kmin), topographic cylinder, central corneal thickness, and thinnest point (TP) were recorded and analyzed. Results A total of 72 eyes of 38 patients were included. The 12-month results showed significant reduction in Kmin (P=0.038), central corneal thickness (P˂0.001), and TP (P˂0.001). At 24 and 36 months, there were no significant changes in corneal topography, except for reduction in TP (P=0.024 and 0.002, respectively). Conclusion Pulsed accelerated CXL is an effective long-term method of arresting keratoconus progression