2Hacettepe Üniversitesi Tıp Fakültesi Göz Hastalıkları A.D., Ankara, Prof. Dr. Purpose: To evaluate the long term reproducibility of ultrasonic pachymetry measurements of central corneal thickness (CCT) in patients with glaucoma and ocular hypertension (OHT).
Materials and Methods: Twenty-nine glaucoma and 10 OHT patients were included in the study. Using ultrasonic pachymetry(Chiron Gauge, France), 10 CCT measurements were performed and the mean of 3 closest minumum values were used in statistical analysis. The measurements were repeated after 6 months. The CCT measurements were compared using paired-sample t test and and p<0.05 was considered as statistically significant. Long term reproducibility was calculated by means of intraclass correlation coefficient (ICC).
Results: The mean CCT measurements of the right (562.72+30.15 μm and 558.67+28.02 μm, respectively) and left eyes (564.54+28.86 μm and 561.10+30.22 μm, respectively) taken 6 months apart were very close to each other, however the difference was statistically significant (p=0.030, p=0.043, respectively). The difference between the 2 measurements were <10 μm in 84.6% of the right eyes and 79.5% of the left eyes. ICC alpha was 0.962 and 0.969 for right and left eyes, respectively (p<0.001).
Conclusion: The CCT measurements by ultrasonic pachymetry are very reliable and reproducible in long term period.
Keywords : Ultrasonic pachymetry, central corneal thickness, glaucoma, reproducibility