Agreement of corneal curvature and central corneal thickness obtained from a swept-source OCT and Pentacam in ectopia lentis patients

AIM:To assess the inter-device consistency of corneal curvature and central corneal thickness between Pentacam and a swept-source Fourier-domain anterior segment optical coherence tomography(AS-OCT)in ectopia lentis patients.METHODS:Totally 72 eyes of ectopia lentis patients were recruited.Central corneal thickness(CCT),corneal curvature values and corneal astigmatism were obtained from both the Pentacam and AS-OCT(CASIA2).Repeatability was evaluated for both devices.The coef ficient of repeatability(COR)and the relative COR was calculated.Bland-Altman plots were conducted to evaluate the interdevice agreement of measurement.Orthogonal linear regression was used to examine any proportional bias.RESULTS:The mean difference of CCT,steep anterior corneal cur vature(anterior K_S),flat anterior corneal curvature(anterior K_f),anterior corneal astigmatism(ACA),steep posterior corneal cur vature(posterior K_S),flat posterior corneal cur vature(posterior K_f),posterior corneal astigmatism(PCA),steep true net power(TNP K_S),flat true net power(TNP K_f)and total corneal astigmatism(TCA)between Pentacam and CASIA2 were 7.03±9.70μm,-0.19±0.41 D,-0.27±0.35 D,0.04±0.47 D,-0.17±0.23 D,-0.11±0.11 D,-0.02±1.02 D-0.41±0.43 D,-0.52±0.46 D,and-0.15±0.96 D,respectively.For measurement of TNP K_f with the Pentacam and CASIA2,a mean difference of 0.52 D and COR of 0.90 with P=0.02 was detected.There was no significant difference in CCT(P=0.393),anterior K_f(P=0.107),anteriorKs(P=0.414),ACA(P=0.131),posterior K_f(P=0.286),posterior Ks(P=0.418),PCA(P=0.105),TNP Ks(P=0.054),and TCA(P=0.977)between Pentacam and CASIA2.CONCLUSION:Our study reveals good agreement of CCT,corneal curvature and corneal astigmatism measured by CASIA2 and Pentacam in ectopia lentis patients.However,there was significant difference for CCT and corneal curvature values obtained by the two devices.