Comparative study of corneal spherical aberration and curvature measured by iTrace and Pentacam

Abstract

AIM: To investigate the difference and consistency between iTrace and Pentacam in measuring corneal spherical aberration(SphA)and curvature.METHODS: The corneal spherical aberration and curvature were measured by iTrace and Pentacam in 63 cases(125 eyes)separately, and the SphA, the minimum corneal curvature(K1), maximum corneal curvature(K2)and corneal astigmatism(CA)were recorded respectively. Paired t-test was used for statistical analysis of econometric data, Bland-Altman analysis was used to evaluate the consistency of measurement results(SphA and curvature)measured by iTrace and Pentacam.RESULTS: The measurement result of SphA, K1, K2 and CA were(0.230±0.086)μm,(43.01±2.38)D,(44.08±2.48)D and(1.03±0.57)D measured by iTrace, and(0.247±0.114)μm,(42.88±1.44)D,(43.86±1.51)D and(1.07±0.62)D measured by Pentacam, there was no significant difference of the measurement result of SphA, K1, K2 and CA between iTrace and Pentacam(P>0.05). The difference of SphA, K1, K2 and CA between iTrace and Pentacam was close to 0, the consistency was good because of the narrow 95% confidence interval.CONCLUSION:There is no significant difference of the measurement result between iTrace and Pentacam, the consistency is good, and both can be used as a mutual reference in clinical.

Keywords

• iTrace
• Pentacam
• corneal spherical aberration
• curvature
• consistency