Comparison of central corneal thickness estimated by an ultrasonic pachymeter and non-contact specular microscopy

Abstract

Purpose: To compare central corneal thickness (CCT) measurements of healthy individuals obtained with ultrasonic pachymetry (UP) and non-contact specular microscopy (NCSM).Method: In total, 148 eyes of 74 subjects with no ocular or systemic diseases were included in the study. Central corneal thickness measurements of all patients performed with UP and NCCM were compared.Results: A total of 74 subjects (38 females) were included in this study. The mean age was 45.2 +/- 18.4 (range 12-85) years. The mean central corneal thickness of all 148 eyes was 546.9 +/- 40 mu m with UP and 510.8 +/- 42 mu m with NCSM. The mean central corneal thickness measured with NCSM was 35 mu m thinner than that measured with UP (p < 0.001). A high degree of agreement was found between the two methods (r = 0.942, p < 0.001).Conclusions: Our results suggest that NCSM measures thinner corneas than UP and that the correction formula we identified should be applied when comparing between these two devices.