Computerized corneal tomography with Pentacam uses a special system (Scheimpflug) to take qualitative measures of the structural characteristics in the anterior segment of the eye: the cornea, the chamber angle, the iris, and the lens. Tomography measures keratometry (the curvature of the cornea), topography (a map of the anterior and posterior surface of the cornea), as well as its thickness (pachymetry), thus helping to detect its irregularities and eye disorders. The anterior chamber is defined by the volume, angle evaluation, and depth. The eye pressure is corrected based on the corneal thickness.
The posterior elevation map is especially important as it can show pathological changes in the earliest stage of keratoconus. The map of the corneal thickness indicates the thinnest spot and helps create a plan of refractive surgery as it combines the data of elevation of the anterior and posterior eye surface. This examination is done at the first appointment with the surgeon regarding the plan for further steps and within preparation for the cataract and refractive surgeries.
Tomography is completely painless and there is no direct contact of the instrument with the eye.