Effects of topical carbamylcholine on corneal epithelial resurfacing

Effects of topical carbamylcholine on resurfacing of epithelial defects produced in both eyes of New Zealand albino rabbits with 18 N H2SO4 were evaluated. One eye of each animal received carbamylcholine (50 microliter of a 1.5% solution in HBSS) t.i.d. (10 AM, 1 PM, and 4 PM) for 7 days, with treatment beginning the morning after defect production. The contralateral eye received 50 microliters HBSS and served as control. Resurfacing was monitored by fluorescein staining and photography. Rates of resurfacing were calculated by linear regression analysis of plots of defect surface area versus time. Data represent treated and control eyes of 19 animals in two experimental series. In these experiments, carbamylcholine significantly enhanced epithelial resurfacing, although the effect was not dramatic. Mean resurfacing rates were 11.9 +/- 1.4 mm2/24 hr for carbamylcholine-treated eyes versus 8.5 +/- 1.3 mm2/24 hr for control eyes (p less than .001). On each day after initiation of treatment, the mean percentage of original defect area remaining was significantly lower in treated than in control eyes. At the end of the 7-day treatment regimen, none of the defects were completely resurfaced (mean for treated eyes = 79.9 +/- 2.2%, mean for control eyes = 56.8 +/- 4.3%).