Effect of applanation tonometry on mean corneal curvature

PURPOSE: To evaluate whether applanation tonometry affects corneal curvature and if so, the implications for intraocular lens power calculation. SETTING: Birmingham and Midland Eye Hospital, Birmingham, England. METHODS: Twenty-two patients attending the preoperative assessment clinic were enrolled in the study. Keratometry was performed immediately before, 1 minute after, and 10 minutes after standard Goldmann tonometry. Main outcome measures were mean corneal refractive power and its reproducibility (coefficient of repeatability). RESULTS: No clinically significant difference was noted between preapplanation and postapplanation readings (P = .6), and reproducibility was not significantly affected. CONCLUSION: The results indicate that corneal applanation before keratometry does not compromise the prediction of postoperative refraction.