Use of Scheimpflug Tomography and OCT Tomography to Examine Corneal Dimensional and Anterior Chamber Depth before and after LASIK Surgery

Abstract

Aims: The aim of this study is to compare corneal parameters in: central corneal thickness (CCT), thinnest corneal thickness (TCT), mean radius of curvature (Rm) and anterior chamber depth (ACD) obtained from Pentacam Schiempflug and OCT Tomography imaging which are checked preoperatively and six months postoperatively after LASIK surgery. Methodology: Our sample consisted of 40 eyes. Changes in corneal dimensions were monitored before and after LASIK surgery using scheimpflug tomography (Pentacam HR) and optical coherence tomography (OCT). The parameters measured were CCT, TCT, Rm and the ACD. The results between the two techniques were compared with the Bland-Altman method. Results: During the analysis of the results, a statistically significant difference was observed between the two techniques in terms of the preoperative CCT as well as the TCT both preoperatively and postoperatively. Scheimpflug tomography gives higher values of the CCT than OCT, up to thickness 530nm, while above this it seems that OCT overestimates the thickness of the cornea. Scheimpflug tomography at the TCT seems to give higher values than OCT tomography, up to thickness 520 nm, while above that it seems that OCT tomography overestimates TCT. We have similar results postoperatively for TCT. The two techniques agree on the ACD and the Rm rating. Conclusion: How converging or different the two imaging devices are because it is important for both clinical practice and research may be a point of reference for starting a new research.