Comparison of Central Corneal Thickness Measurements by Ultrasound Pachymeter, Optical Coherence Tomography and Corneal Topography
Phanvipha Pholshivin MD*, Wimolwan Tangpagasit MD**
Affiliation : *Department of Ophthalmology, H.M. Queen Sirikit Hospital, Cholburi, Thailand **Department of Ophthalmology, Faculty of Medicine, Thammasat University, Bangkok, Thailand
Objective : To compare central corneal thickness (CCT) measured by standard ultrasound pachymeter with optical coherence
tomography (OCT) and corneal topography.
Material and Method: A cross-sectional study of central corneal thickness measurement by ultrasound pachymeter, OCT
and corneal topography in 30 eyes of 30 healthy volunteers was done by a single examiner at Thammasat University Hospital
between October 2010 and January 2011. The results were compared using ANOVA for repeated measures and Pearson
correlation.
Results : Mean central corneal thickness by ultrasound pachymeter, OCT and corneal topography were 552.1 + 33.6 μm,
554.5 + 33.0 μm and 552.8 + 39.0 μm respectively. There were no statistically significant differences in the measurement
results among the three modalities (p = 0.718). There was a significant linear correlation between OCT and ultrasound
pachymeter (Pearson correlation = 0.985, p < 0.001), corneal topography and ultrasound pachymeter (Pearson correlation
= 0.965, p < 0.001) and corneal topography and OCT (Pearson correlation = 0.965, p < 0.001).
Conclusion : Mean central corneal thickness among ultrasonic pachymeter, OCT and corneal topography were comparable
and had significant linear correlations. In clinical practice, these three modalities could be interchangeable.
Keywords : Central corneal thickness, Ultrasound pachymeter, Optical coherence tomography, Corneal topography
