The effect of pterygium surgery on corneal topography

OBJECTIVE: The aim of this prospective randomized clinical study was to eva luate the effect of pterygium surgery on the corneal topography using a com puterized corneal topography system. PATIENTS AND METHODS: Computerized corneal topography was performed on 27 p atients with primary pterygium before and after pterygium excision surgery. The topographical changes that occurred following surgery were evaluated u sing paired and unpaired two-tailed t-test and Pearson coefficient of corre lation analyses. Simulated keratometric astigmatism at the central 3 mm and the total mean refractive powers of the whole cornea were measured before and after surgery. Following surgery, fattened or steepened corneal areas w ere determined. RESULTS: Simulated keratometric astigmatism at 3 mm was found to be 2.30 +/ - 2.08 D (0.2 - 7.63) preoperatively and 0.82 +/- 0.74 D (0.06 - 2.79) post operatively. The difference between these two values was statistically sign ificant (t = -3.46, P = 0.002). Total mean refractive power of the whole co rnea was found to be 42.26 +/- 0.63 (40.80 - 43.64) preoperatively and 43.6 9 +/- 0.88 (41.50 - 44.90) postoperatively and the difference was 1.42 +/- 0.87. There was a statistically significant high difference (t = 28.36, P < 0.001). When preoperative and postoperative corneal topographies were comp ared, the whole cornea was found steeper at the postoperative period except a little region in the superior nasal quadrant. CONCLUSION: We believe that corneal topographical changes caused by the pte rygium are almost reversible after surgical treatment, and postoperatively the cornea becomes steeper.