Advances in the technology of corneal cross-linking for keratoconus.

Corneal cross-linking (CXL) with ultraviolet-A (UVA) and riboflavin was introduced over 15 years ago and has been widely adopted as a treatment for keratoconus. Several studies have demonstrated the safety and efficacy of the procedure performed according to a standard protocol. Recent scientific and technological advances have highlighted the opportunity for optimization of the CXL procedure through modifications to this protocol. Advances in the technology of CXL include new riboflavin formulations, higher irradiance UVA sources, and programmable UVA illumination patterns. Several laboratory and clinical studies demonstrate that these modifications may provide equivalent treatment effect in shorter total treatment times. Additionally, although the original purpose of CXL was to stabilize the cornea and prevent further visual loss in keratoconus, patient-specific computational modeling and customized CXL with programmable UVA treatment patterns demonstrate the potential for CXL to be used as a means of improving corneal topography to maximize visual rehabilitation in patients with keratoconus. This review aims to provide an overview of these advances in CXL technology designed to optimize the efficiency or efficacy of the clinical CXL procedure.