Customized Patterned Myopic, Astigmatic, and Hyperopic Refractive Correction With Transepithelial, Variable-Fluence CXL
Purpose
To report safety and efficacy of a customizable application of high-fluence collagen crosslinking (CXL) through the intact epithelium (transepithelial) with a novel device, aiming in refractive myopic, astigmatic, and hyperopic changes in virgin corneas.
Methods
Twnety cases were treated with a novel device employing very high-fluence CXL, applied in a customized pattern aiming to achieve predictable refractive changes for myopia (10 cases), hyperopia (5 cases), and astigmatism (5 cases). Riboflavin penetration through the intact epithelium was applied with specially formulated solutions in a two-step procedure. A novel CXL device was employed to deliver a maximum of 15 J/cm2, in pre-determined variable fluence pattern. One year postoperatively we evaluated cornea clarity (slit lamp), cornea keratometry, topography (with Placido disc, Scheimpflug imaging), epithelial thickness with anterior-segment Optical Coherence Tomography, and endothelial cell counts (ECC).
Results
Of the 10 myopic cases an average of -1.50D correction was achieved. Mean keratometry change was from 44.90D to 43.46D. Epithelial thickness showed a homogeneous reduction, from 52μm to 44μm on average over the treated area. Of the 5 astigmatic cases treated, a mean astigmatic reduction of -1.8D, and significant cornea surface normalization was achieved, along with modest epithelial thickness normalization. Of the 5 hyperopic cases treated, a mean hyperopic refractive increase of +1.2D was achieved. There was no significant change in ECC, nor was any change in the cornea clarity in any case.
Conclusion
We introduce herein the novel application of very high-fluence CXL with a predictable well-defined myopic refractive (flattening), astigmatic, and hyperopic (steepening) corneal remodeling. This novel technique carries the advantage of essentially no post-operative morbidity, immediate visual rehabilitation and a potential to be tapered until the desired result is reached.