To the Editor:Currently,from a pathological point of view,corneal collagen crosslinking(CXL)with riboflavin is the only new therapy for controlling keratoconus progression.Riboflavin,as a photosensitizer,can be activa...To the Editor:Currently,from a pathological point of view,corneal collagen crosslinking(CXL)with riboflavin is the only new therapy for controlling keratoconus progression.Riboflavin,as a photosensitizer,can be activated after the ultraviolet radiation in the cornea and prevent it from damaging intraocular organizations.Therefore,the concentration of riboflavin in the corneal stroma must be maintained at a sufficient level during the treatment.[1]Riboflavin,a type of water-soluble macromolecule,is resistant to permeating the corneal epithelial barrier.Thus,de-epithelial eye-dripping was adopted conventionally with complications such as inevitable pain,long recovery time,potential risk of infection,and so on;transepithelial corneal CXL is increasingly becoming a research hotspot.It is thus critically important to improve the transepithelial penetration of riboflavin.Although iontophoresis was reported,it had a slightly higher effect with no clear mechanism analysis.[2,3,4]Corneal epithelium is lipophilic and hydrophobic,and hydrophilic drugs enter corneal stroma via intercellular pathways.In this study,permeability effects of riboflavin in different solvents into the cornea via iontophoresis were compared,and the changes of corneal epithelial cell layer organizations were analyzed to examine the solvent components that are most beneficial to iontophoresis and investigate the underlying mechanism of the penetration effect.展开更多
文摘To the Editor:Currently,from a pathological point of view,corneal collagen crosslinking(CXL)with riboflavin is the only new therapy for controlling keratoconus progression.Riboflavin,as a photosensitizer,can be activated after the ultraviolet radiation in the cornea and prevent it from damaging intraocular organizations.Therefore,the concentration of riboflavin in the corneal stroma must be maintained at a sufficient level during the treatment.[1]Riboflavin,a type of water-soluble macromolecule,is resistant to permeating the corneal epithelial barrier.Thus,de-epithelial eye-dripping was adopted conventionally with complications such as inevitable pain,long recovery time,potential risk of infection,and so on;transepithelial corneal CXL is increasingly becoming a research hotspot.It is thus critically important to improve the transepithelial penetration of riboflavin.Although iontophoresis was reported,it had a slightly higher effect with no clear mechanism analysis.[2,3,4]Corneal epithelium is lipophilic and hydrophobic,and hydrophilic drugs enter corneal stroma via intercellular pathways.In this study,permeability effects of riboflavin in different solvents into the cornea via iontophoresis were compared,and the changes of corneal epithelial cell layer organizations were analyzed to examine the solvent components that are most beneficial to iontophoresis and investigate the underlying mechanism of the penetration effect.
