Comparison of central corneal thickness measurements by visante anterior segment optical coherence tomography with ultrasound pachymetry.

ABSTRACT

PURPOSE: To compare the measurement of the central corneal thickness (CCT) by Visante (Carl Zeiss Meditec, Dublin, California, USA) anterior segment optical coherence tomography (AS-OCT) with ultrasound pachymetry. DESIGN: Population-based, cross-sectional study. METHODS: Participants were part of a population-based study of 3280 Malay subjects aged 40 to 80 years in Singapore. Ultrasound pachmetry of CCT was performed on all participants and approximately 10% underwent further evaluation with AS-OCT. RESULTS: Two hundred and eighty-five consecutive subjects were included, with a mean age of 57.9 (+/- 10.8) years. CCT as measured by ultrasound pachymetry was highly correlated with the equivalent AS-OCT reading (The Pearson correlation coefficient = 0.93, P < .001). However, Bland-Altman analysis showed that CCT as measured by ultrasound pachymetry was significantly higher by 16.5 +/- 11.7 microm (limits of agreement -6.1 to 39.1, P < .001). CONCLUSIONS: CCT measured by Visante AS-OCT was highly correlated with that from ultrasound pachymetry. However, CCT readings by Visante AS-OCT were consistently less than that of ultrasound pachymetry.