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

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.