Photochemical Crosslinking of Tarsal Collagen as a Treatment for Eyelid Laxity: Evaluation in Ex Vivo Human Tissue.

Purpose: Experimental investigation in human eyelids to confirm that exposing excised tarsal plates to ultraviolet-A radiation can induce a stiffening effect through the riboflavin-photosensitized crosslinking of tarsal collagen.

Methods: Thirteen tarsal plates excised from nonfrozen human cadavers were irradiated with ultraviolet-A rays (365 nm wavelength) at an irradiance of 75 mW/cm 2 for 3 minutes, equivalent to a radiation fluence of 13.5 J/cm 2 , in the presence of a riboflavin derivative as a photosensitizer.