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Purpose To assess the interchangeability of central corneal thickness (CCT) measurements between combined scanning-slit/Placido disc topography (Orbscan-II) and specular microscopy (Topcon SP-2000P) in patients who underwent laser in situ keratomileusis (LASIK) for myopia. Patients and methods We recruited 118 consecutive patients who underwent LASIK for myopia. The CCT was measured using Orbscan-II and Topcon SP-2000P randomly. Orbscan-II and Topcon SP-2000P CCT data were analysed using the paired-sample t-test and the limits of agreement (LoA) were calculated with the method described by Bland-Altman. Results The average CCT measurements by Orbscan-II and Topcon SP-2000P were 447.55 ± 49.78 lm and 461.38 ± 35.35 lm, respectively (Po0.0001; mean difference, 13.83±22.31 lm; 95% confidence interval, 9.77-17.09 lm). The Bland-Altman plot showed an inverse association between the average and the difference between the devices: TopconOrbscan-II ¼ 174.23 -0.353 Â Average (Po0.01). The widths of the crude and regression-based 95% limits of agreement were 87.45 and 63.72 lm, respectively. Conclusions Orbscan-II measurements of CCT after myopic LASIK were significantly lower than those obtained using Topcon SP-2000P. The limits of agreement between the two devices were too broad and, therefore, both pachymetric values cannot be used interchangeably. Further, the tendency towards comparably Orbscan-II readings in thinner corneas precludes that one technique can directly replace the other. This is important for the adequate medium-and longterm follow-up of the growing LASIK patient population.