Comparison of central corneal thickness in normal eyes before and after topical anesthesia with Pentacam scheimpflug system

Objective To compare the difference of central corneal thickness(CCT)in normal eyes between A-ultrasound pachymetry and the Pentacam scheimpflug,discuss the changes of CCT before and after topical anesthesia with Pentacam scheimpflug system and A-ultrasound and provide the reference for the option of refractive surgery.Methods The CCT of 50 healthy eyes form 25 normal subjects were measured with A-ultrasound pachymetry and Pentacam scheimpflug system,the CCT before and after topical anesthesia were also measured by Pentacam scheimpflug system and A-ultrasound.The results were statistically analyzed.Results The CCT values obtained with Pentacam scheimpflug system and A-ultrasound pachymetry before topical anesthesia were(544.50±26.24)μm and(544.84±28.02)μm,respectively,there was no significant difference(P0.05)and a high correlation between them(P0.01).Also,the mean CCT values measured by Pentacam scheimpflug system after topical anesthesia was(549.76±27.09)μm,the difference was significant compared with that before topical anesthesia(P0.01),there was a high correlation between them(P0.001).There was no difference in CCT measured by A-ultrasound pachymetry before and after topical anesthesia(P=0.765).Conclusions Pentacam scheimpflug system can provide accurate,full-scale and convenient method to CCT measurement,which is helpful in clinical application.The CCT values after topical anesthesia are little thicker than the CCT values before topical anesthesia with Pentacam scheimpflug system,although the difference is not significant,when come to the clinical application value,it wouldn't affect the option for refractive surgery.