Effect of lens wear on corneal stroma: preliminary findings

Purpose: The aim of the study was to measure the effects of long-term extended wear of hydrogel lenses. Methods: Nine subjects wearing disposable hydrogel lenses and age- and sex-matched non-lens-wearing control subjects were enrolled. Using confocal microscopy, stromal keratocyte cell densities were measured, Results: Anterior stromal keratocyte density was reduced in the lens-wearing group (544 +/- 206 cells/mm(2)) compared to the non-lens-wearing group (804 +/- 145 cells/mm(2)) (P < 0.01). Posterior stromal keratocyte density was lower in the lens-wearing group (514 +/- 111 cells/mm(2)) than in the control group (628 +/- 101 cells/mm(2)) (P < 0.05). Conclusions: These preliminary findings indicate that extended wear of hydrogel lenses reduces stromal keratocyte density. The mechanisms for this alteration may include hypoxic, cytokine-mediated or mechanical effects.