Corneal Topography and Tomography

Corneal topography measures the shape and optical properties of the cornea with different technologies that have evolved through the years: from Placido reflection topographers to elevation Scheimpflug and OCT tomographers. In this chapter, the difference among these instruments is analyzed exposing the features of each method as well as the precision and agreement of the measurements. Definitions and metrics used for shape, curvature, elevation, optical power, and aberrometry are discussed. These instruments provide the surgeon with software-oriented to intraocular lens (IOL) power calculation taking advantage of the anterior and posterior corneal measurements. Corneal analysis also plays an important role in the selection of the most adequate IOL optical design.