Effect of lens wear on corneal stroma: preliminary findings

Purpose: The aim of the study was to measure the effects of long-term exten ded 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 mic roscopy, stromal keratocyte cell densities were measured, Results: Anterior stromal keratocyte density was reduced in the lens-wearin g group (544 +/- 206 cells/mm(2)) compared to the non-lens-wearing group (8 04 +/- 145 cells/mm(2)) (P < 0.01). Posterior stromal keratocyte density wa s lower in the lens-wearing group (514 +/- 111 cells/mm(2)) than in the con trol group (628 +/- 101 cells/mm(2)) (P < 0.05). Conclusions: These preliminary findings indicate that extended wear of hydr ogel lenses reduces stromal keratocyte density. The mechanisms for this alt eration may include hypoxic, cytokine-mediated or mechanical effects.