Comparison of the corneal thickness measured by anterior segment optical coherence tomography and specular microscope versus ultrasound pachymetry

Abstract

Abstract Purpose To compare measurements of central corneal thickness (CCT) between the noncontact and contact ultrasound pachymetry and to define endothelial cells density in normal eyes. Methods 60 eyes of 30 clinically healthy persons – 20 women and 10 men, whose age ranged from 22 to 26 years, were studied. Measurements were performed by specular microscope, anterior segment optical coherence tomography and ultrasound pachymetry. Results obtained with these devices were compared. For statistical analysis of Pearson correlation coefficient and Bland‐Altman plot was used MedCalc software, version 8.1. Results The mean central corneal thickness (CCT) as measured by CP was 544.9 ± 43.2µm of the right eye and 544.7 ± 41.1µm of the left eye. The mean CCT as measured by OCT was 544.2± 42.1µm of the right eye and 549.50 ± 44.5µm of the left eye. The mean CCT as measured by SM was 558.87± 45.8µm of the right eye and 556.93 ± 45.6µm of the left eye. Pearson correlation coefficient was statistically significant (0.919 ‐ 0.964) for all compared groups. By Bland‐Altman plot method statistically significant deviation was not found for any set of groups. The mean endothelial cell density was 2917.3 ± 532.1 cell/mm² for the right and 2947.6 ± 331.5 cell/mm² for the left eye respectively. Conclusion 1.The results of central corneal thickness measurements obtained using all three methods are in linear dependence. 2. The intrasession variation of central corneal thickness measured by specular microscope was higher than that of contact method and Visante OCT.