Measuring central corneal thickness and anterior chamber depth in myopia with Pentacam Scheimpflug imaging system

Abstract:

AIM:To assess the accuracy of Pentacam Scheimpflug imaging system in the measurement of central corneal thickness and anterior chamber depth in myopia.METHODS:Pentacam Scheimpflug imaging system and A-scan ultrasonic pachymetry were used to measure the central corneal thickness and anterior chamber depth in 82 patients 164 eyes with myopia.The results of two methods were compared.The results were analyzed with SPSS 16.0.Correlation analysis was performed in intraocular pressure and axial length.RESULTS:The value of central corneal thickness measured by the Pentacam Scheimpflug imaging system was 524±0.037μm,and by A-scan ultrasonic pachymetry was 521±0.036μm.There was significant difference between the results of these two methods(P<0.01).The value of anterior chamber depth measured by the Pentacam Scheimpflug imaging system was 3.26±0.25mm,and by A-scan ultrasonic pachymetry was 3.36±0.53mm.There was significant difference(P<0.05),and significant linear correlation between the two methods(P<0.01).The average central corneal thickness was 3μm by optics;average anterior chamber depth was 0.1mm by ultrasound.The two methods for measuring the central corneal thickness and intraocular pressure and the anterior chamber depth and axial length were positively related(P<0.01).CONCLUSION:There exists certain difference in the central corneal thickness and the anterior chamber depth for ametropia measured by Pentacam,a three-dimensional anterior segment analyzer and A-scan ultrasonic pachymetry.

Key words:anterior segment analyzer;A-scan ultrasound;corneal thickness;anterior chamber depth;myopia