THE ESP

Profilometry Maps

All ESP Profilometry maps are based on height data, measured directly with no extrapolation. The measured data is directly translated into height maps:

Height Map

Sagittal height, often referred to as SAG, is a crucial measurement in the field of specialty contact lens fitting. The height map displays the SAG of the complete cornea and sclera relative to an imaginary plane that is perpendicular to the line of sight and passes through the apex of the cornea, conveying the true ocular shape:

While other Placido disc systems use complicated algorithms to calculate the corneal elevation, itis important to note that the Eye Surface Profiler measures sagittal height directly, giving more accurate data of the cornea and the sclera.

Bi-sphere Elevation Map

This map represents the deviation of each corneal and scleral pint relative to two calculated best-fit spheres (BFS), one for the cornea, and one for the sclera. It displays areas of relative elevation or depression in micron precision:

This is the primary map when first determining the best lens design e.g. deciding between a corneal or scleral gas permeable (GP) lens. The data will also help select the diameter, geometry, initial SAG, the need for toric, spherical, or quadrant specific curves, and any areas that will need local accommodations.