Galilei Corneal Tomography for Screening of Refractive Surgery Candidates: A Review of the Literature, Part II.

Corneal topography is the most widely used technology for examining the anterior corneal surface. Scheimpflug imaging is a newer technique that allows for measurement of both the anterior and posterior corneal surface, which allows for three-dimensional reconstruction of the cornea. This is of particular interest and value in the field of cataract and refractive surgery. The Galilei camera is a commercially available dual Scheimpflug system that combines curvature data from Placido disc-based corneal topography with elevation data from Scheimpflug technology. The addition of Placido disc topography makes the Galilei unique from its more popular counterpart, the Pentacam, which was discussed in Part I. Compared to the Pentacam, and however, the Galilei analyzer is a newer system that has emerged as a valuable screening tool given its dual Scheimpflug capability. In the first article of this series, the authors summarized the refractive indices available on the Pentacam system with the purpose of identifying the best diagnostic parameters for keratoconus. Similarly, the purpose of this article is to summarize corneal surface indices available on the Galilei system and evaluate their use in screening of the refractive surgery candidate. Since post-operative keratectasia is still prevalent, this paper aims to identify the most clinically relevant indices that may be used in pre-operative evaluation.