Commercial OCT systems provide pachymetry measurements. Full corneal topographic information of anterior and
posterior corneal surfaces for use in cataract surgery and refractive procedures is a desirable goal and would add to
the usefulness of anterior and posterior segment evaluation. While substantial progress has been made towards
obtaining "average" central corneal power (D Huang), power in different meridians and topography are still missing.
This is usually reported to be due to eye movement. We analyze the role of centration, eye movements and develop
a model that allows for the formulation of criteria for obtaining reliable topographic data within ¼ diopter.