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Effect of applanation tonometry on mean corneal curvature
S Beatty1, K K Nischal, H Jones
1Birmingham and Midland Eye Hospital, England.
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.
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