Corneal Topography

What is Corneal Topography?

If you regularly visit your eye doctor for post-surgery check-ups or other eye conditions, you already know what to expect during your visits. Your specialist will ask you to sit down in front of a large machine. You rest your chin and forehead against pads and stare wide-eyed into a bowl-shaped contraption that has layers of bright rings around its interior.

You may be accustomed to the process but do you have an understanding of what is happening on the other end of the machine? Most people do not.

At Global Contact Lens Specialists the procedure is known as corneal topography though some may refer to it as photokeratoscopy or videokeratography. It is a process that has been around for more than a century and is used to provide both qualitative and quantitative evaluations on the outer surface of the cornea.

When using topography, up to 10,000 specific points can be measured across the entire corneal surface within the matter of seconds.

The rings that you see on the interior of the bowl are concentric rings that project onto the cornea to create virtual images that are immediately processed and calculated by the computer. With these digital images, the doctors at Global Contact Lens Specialists are able to print out different types of color-coded, three dimensional maps to assist with diagnostics and treatment.

The maps are easy indicators of issues with the cornea such as keratoconus or Fuch’s dystrophy. Keratoconus is a condition that causes the cornea to bulge outward in the shape of a cone. Fuch’s dystrophy is a condition that causes the thin layer of cells in the back end of the cornea to die off.

There are other reasons we conduct corneal topography at Global Contact Lens Specialists , including finding the perfect fit for contact lenses. Before topography, contact lenses were fitted with a keratometer. This instrument also measures the curvature of the cornea yet was limited in its ability to measure a large area of the surface. Unlike the keratometer, topography can measure the cornea’s curvature, shape and depth for Global Contact Lens Specialists to create the perfect fit for each patient’s contact lenses.

Corneal topography is fast, painless and completely non-invasive. At Global Complex Eye Care, we have been performing corneal topography for many years and have in-depth experience studying, analyzing and drawing accurate conclusions with its results.