2M.D. Professor, Ankara Numune Training and Research Hospital, Eye Clinic, Ankara/TURKEY
3M.D. Professor, Cumhuriyet University Faculty of Medicine, Department of Biostatistics, Sivas/TURKEY
4M.D. Asistant Professor, Cumhuriyet University Faculty of Medicine, Department of Biostatistics, Sivas/TURKEY Purpose: The aim of this study was to compare the results of ultrasonic pachymetry (UP) and optical coherence tomography (OCT) for central corneal thickness measurement in healthy individuals in the general population.
Materials and Methods: We measured the central corneal thicknesses of the right eyes of 60 healthy subjects consecutively with ultrasonic pachymetry (Sonomed 300P PacScan) and optical coherence tomography (SD-Nidek RS-3000 Advance). Ultrasonic pachymetry measurement results were specified as group UP and optical coherence tomography measurement results as group OCT and the compared with each other. The t test and the Bland-Altman plot were used as the statistical methods.
Results: The study was conducted on 60 subjects consisting of 33 (55%) males and 27 (45%) females. The mean age was 36.7±15.8 (10-76) years for all subjects, 37.4±13.9 (16-76) years for the males and 35.9±18.1 (10-68) for the females. Mean UP measurement for all subjects was 544±33.6 μm (467-616) while the mean OCT measurement was 533.9±30 μm (457-600). The difference between the results was statistically significant (p=0.001) with mean OCT measurements 10.1 m lower than mean UP measurements. There was a high degree of agreement between the two methods with the Bland-Altman plot.
Conclusion: Mean central corneal thickness measurements with optical coherence tomography were approximately 10 μm lower than ultrasonic pachymetry measurements. Further studies on larger series are needed.
Keywords : Central corneal thickness, glaucoma, pachymetry