Protection from harmful UV radiation by contact lenses.
Ultraviolet radiation (UVR) has been demonstrated to be harmful to the cornea, the lens and the retina. Recent research has indicated that, in addition to the epithelial trauma found in UVR-induced keratitis, the deeper corneal layers are also involved. Since trauma to keratocytes and endothelial cells can result in permanent damage or cell loss, it is imperative to protect eyes against excessive dosages of UVR. Standard hydrogel contact lenses (Vistamarc normal) and newly developed UV-filtering hydrogel lenses (Vistakon UV-BLOC) were fitted on five rabbits and compared in protection from harmful UVR (300 nm). The eyes that wore the UV-filtering lens maintained normal corneas; however, the eyes that wore the standard hydrogel lens showed pronounced epithelial, stromal and endothelial changes. We concluded that the UV-filtering lens effectively absorbed the hazardous UV radiation while the standard soft lens provided little protection.
Bergmanson
J P
JP
Institute for Contact Lens Research, University of Houston, College of Optometry, TX 77004.
Pitts
D G
DG
Chu
L W
LW
D000818:Animals; D003263:Contact Lenses, Hydrophilic; D003315:Cornea / Q000648:ultrastructure; D005374:Filtration; D006801:Humans; D007634:Keratitis / Q000175:diagnosis / Q000209:etiology* / Q000473:pathology / Q000628:therapy; D011817:Rabbits; D014466:Ultraviolet Rays / Q000009:adverse effects*