Corneal metabolism and epithelial barrier function after cataract surgery and intraocular lens implantation: A fluorophotometric study

Purpose: The aim of this study was the assessment of possible changes in corneal metabolism and epithelial barrier function after an extracapsular lens extraction with artificial lens implantation. Methods: Ten patients without any eye medication were selected out of 140 patients attending for extracapsular lens extraction with lens implantation at the university hospital. Corneal metabolism was evaluated by fluorophotometric measurement of corneal autofluorescence. The corneal fluorescence values were corrected for interference by the fluorescence of the ocular lens. Corneal epithelial barrier function was evaluated by determination of corneal epithelial permeability. The permeability was calculated from the fluorescein penetration into the cornea after application of an eye bath containing fluorescein. Operated and fellow eyes were investigated 1 week before and 3-4 weeks after the operation. Results: The corneal autofluorescence of the operated eye decreased significantly after surgery (mean decrease: 14%, Wilcoxon paired-sample test: P = 0.038). The corneal epithelial permeability of both eyes increased after surgery above the normal range of healthy controls (mean increase operated eye: 34%, P = 0.015, fellow eye: 32%, P = 0.15). Both corneal autofluorescence and epithelial permeability returned to normal values after one year. Conclusions: The lower corneal autofluorescence in the operated eye after surgery indicates a lower corneal metabolism which may be due to surgery. The increased epithelial permeability of both eyes implies a temporary impairment of the corneal barrier function. The interaction with the fellow eye indicates a consensual reaction which may attributed to damage to the neural system by the surgery.