Six-Month Outcomes of Accelerated Corneal Crosslinking with a Total Dose of 7.2 J/cm² Using Dextran-Free Riboflavin.

Abstract

Purpose: To evaluate the six-month clinical outcomes of accelerated corneal cross-linking (CXL) using a total energy dose of 7.2 J/cm² with a 0.1% dextran-free riboflavin solution containing hydroxypropyl-methylcellulose (HPMC) in patients with progressive keratoconus.

Methods: Forty-two eyes from 35 patients with progressive keratoconus underwent epithelial removal, followed by the application of 0.1% dextran-free riboflavin solution with HPMC every 30 seconds for 10 minutes. Accelerated CXL was performed using UV-A irradiation at 12 mW/cm² for 10 minutes, delivering a total energy dose of 7.2 J/cm². Evaluations included uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), keratometric indices (K1, K2, Kmax), central corneal thickness (CCT), endothelial cell density (ECD), corneal astigmatism, and demarcation line (DL) depth using anterior segment optical coherence tomography (OCT). Each keratometric index was measured three times, and mean values were recorded.

Results: CDVA improved significantly from 0.55 ± 0.29 logMAR to 0.36 ± 0.23 logMAR (p <0.001). Keratometric indices showed significant reductions, with mean Kmax decreasing from 57.06 ± 5.7 D to 55.4 ± 5.5 D (p <0.001). Astigmatism significantly decreased from 4.2 ± 1.1 D preoperatively to 3.8 ± 1.0 D postoperatively (p = 0.02). CCT was significantly reduced from 471.6 ± 32.4 µm to 461.4 ± 31.7 µm (p <0.001), while UDVA remained unchanged (p = 0.07). The mean DL depth was 287.82 ± 39.77 µm. No significant change was observed in ECD (p = 0.09), and no minor postoperative complications were encountered.

Conclusions: Accelerated CXL using a total energy dose of 7.2 J/cm² with 0.1% dextran-free riboflavin effectively stabilizes keratoconus progression, significantly improves visual acuity and corneal astigmatism, and preserves endothelial integrity over a six-month follow-up. Further long-term studies are required to validate these findings.