First Author: I.Paladini ITALY
Co Author(s): L. Livi A. Calossi A. Fossetti S. Esente R. Mencucci
Purpose:
Wearing orthokeratology contact lenses (OCL) overnight can change corneal refraction by up to -4.5 dioptre based on corneal adaptation to the double reverse surface of the OCL. This allows a temporary independence on glasses or contact lenses. It is known that the central corneal thickness decreases while the corneal thickness in the periphery probably increases. The aim of this study was to investigate the corneal changes of volunteers wearing OCL with in vivo confocal microscopy.
Setting:
University of Florence, Italy
Methods:
Fifteen young adults with low to moderate myopia were fitted with OCL of reverse-geometry design in both eyes. Lenses were worn in both eyes overnight and were removed immediately in the morning. The volunteers were examined with in vivo confocal microscopy before wearing the OCL and after the 1, 3, 6 months.
Results:
No alterations were found on the endothelium. The central and the mid-peripheral epithelial corneal thickness was altered significantly (p<0.05) at month 1. No significant changes (p>0.05) were found in the central or mid-peripheral total corneal thickness in the later examinations. The central corneal epithelium responds to OCL wear by undergoing significant epithelial cell shape and size alterations with no effects, however, on the cells of the corneal endothelium or the corneal stroma. Peripheral corneal thickness increased with respect to baseline values. These findings suggest that the corneal epithelium is the principal structure affected by the mechanical forces exerted by the OCL lenses.Mild anterior stroma activation was noted in some patients with hypereflective keratocytes.
Conclusions:
Wearing OCL leads to a reduction in the central corneal epithelial thickness. Our inability to find an increase in mid-peripheral total and epithelial corneal thickness may be because the expected increase of the mid-peripheral cornea is limited to a defined area, which makes repeated measurements at a particular point difficult. FINANCIAL DISCLOSURE?: No
Please wait while information is loading.
