Abstract
Purpose
To investigate the migration and redistribution of rabbit corneal epithelial cells when wearing reverse geometry lens (RGL) or rigid gas permeable lens (RGP).
Methods
In 30 rabbits, the right eyes were fitted with either RGL or RGP and the left eyes were untreated to serve as controls. The rabbits were sacrificed at 1, 3, 7, 10 and 14 days after lens fitting. The central and peripheral corneal thick-nesses were measured by microscope and the ratio of right to left corneal thickness was calculated to evaluate the characteristics of change over time. By using the molecular probe 7-nitrobenz-2-ox-1,3-diazolylphallacidin (NBD phallacidin), the samples were examined with light microscope to determine the migration and redistribution of epithelial cells in the rabbit cornea.
Results
No consistent changes in the thickness of both central and peripheral corneal epithelium were found. The corneal epithelial cells of both eyes with RGL and RGP reacted positively to NBD phallacidin. The fluorescence was most increased at day 3 of sacrifice in RGL cases and at day 7 in RGP cases, and then decreased in both cases. The corneal epithelium of eyes with RGL exhibited marked increase in the intensity of fluorescence compared to the eyes with RGP.
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Table 1.
DK value* | DK/L† | Center thickness (mm) | Water absorption (%) | Diameter (mm) | |
---|---|---|---|---|---|
RGP lens | 64 | 64 | 0.1 | <1.10 | 10.0 |
RGL | 140 | 70 | 0.2 | 4.9 | 10.0 |