Comparison of central corneal thickness measurements by PachPen ultrasonic pachymetry and the other two optical measuring instruments / 国际眼科杂志(Guoji Yanke Zazhi)

ABSTRACT

·AIM:To compare the similarities and differences of central corneal thickness (CCT) measured by different devices, so as to provide a safe, effective, simple and accurate method for measuring corneal thickness. ·METHODS: Totally 95 eyes of 95 cataract patients enrolled continuously for preoperative examination in ophthalmology department of Putuo Hospital Affiliated to Shanghai University of Traditional Chinese Medicine from September 2016 to December 2016. Handheld automatic PachPen ultrasonic pachymetry (USP), anterior segment optical coherence tomography (AS-OCT) and specular microscopy were respectively used to measure the central corneal thickness,and intraocular pressure was measured at the same time. The similarities and differences of these three different devices to measure the central corneal thickness and their correlations with intraocular pressure were observed. Then the data were analyzed statistically. · RESULTS: The CCT value measured by PachPen ultrasonic pachymetry was 544. 43 ± 36. 61μ m, the CCT value measured by AS-OCT was 527.09 ± 35.54μ m, and the CCT value measured by specular microscopy was 533.20 ± 30. 17μ m. There was significant difference between these three groups(F=6.272,P=0.002),and the CCT value measured by PachPen ultrasonic pachymetry was significantly higher than the other two groups. The correlation coefficients between the CCT values of these three groups and intraocular pressure were 0.290, 0.277 and 0.204 (P<0.05) respectively, of which the correlation between the CCT measured by PachPen ultrasonic pachymetry and the intraocular pressure was the highest. There was statistically significant correlation between the CCT values measured by these three measurements (P<0.001). ·CONCLUSION: The CCT value measured by PachPen ultrasonic pachymetry is the highest. The second CCT value is measured by specular microscopy, and the smallest CCT value is measured by AS-OCT. Obvious correlation and good consistency were found in the CCT values measured by three types of devices, and the CCT values were all correlated with intraocular pressure. Therefore,we should take more attention in clinic.