Researchers continue to explore the utility of a customized corneal crosslinking (CXL) procedure that focuses specifically on the weak area of the keratoconic cornea. Now, a new study in the Journal of Cataract & Refractive Surgery has found that customized CXL using a transepithelial approach with supplemental oxygen resulted in significant improvements in corneal curvature and corrected distance visual acuity without significant adverse events.
The study enrolled 27 eyes of 24 patients with progressive keratoconus who underwent the customized corneal CXL procedure. The procedure included the delivery of ultraviolet-A irradiation of 365nm wavelength in an accelerated (30mW/cm2) pulsed-light exposure in a two-zone elliptical pattern. A total dose of 10J/cm2 was delivered at the keratoconic apex, surrounded by a broad-beam spot of 7.2J/cm2. After 0.25% riboflavin corneal soaking, the UV-A irradiation was initiated in the presence of additional oxygen (90% or less concentration) delivered through special goggles. The investigation’s key outcome measures included corrected distance visual acuity (CDVA), keratometry (AK, K1, K2, K-average), corneal higher-order aberrations, topographic and manifest cylinder, corneal OCT demarcation line and endothelial cell count.
Researchers observed a significant improvement of CDVA at the six-month follow-up visit, from a baseline of 0.19± 0.06 LogMAR to 0.11±0.04 LogMAR. Additionally, the study reported significant flattening of steep keratometry (K2) with a mean change of -1.9D; coma values also improved from 0.47±0.28µm to 0.28±0.16µm.
Additionally, OCT revealed two demarcation lines at mean depths of 218.23±43.32µm and 325.71±39.70µm.
Mazzotta C, Sgheri A, Bagaglia SA, et al. Customized corneal crosslinking for treatment of progressive keratoconus. Clinical and OCT outcomes using a transepithelial approach with supplemental oxygen. Journal of Cataract & Refractive Surgery. August 27, 2020. [Epub ahead of print].