Corneal Topography

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The above pictures are topographical maps of my corneas. The pictures were created using a special digital camera connected to a PC. What makes the camera so special is a set of concentric light rings surrounding the lens. After removing your contact lenses, you place your head into a chin rest connected to the camera. The center of the cameras lens has a small red light to help keep your focus straight ahead. The fun part is trying not to blink as the technician takes the picture.

Earlier models of these cameras did not have a red light at the center of the lens. These earlier models were very frustrating to me. Without the red dot, you were supposed to focus on the lens of the camera. With my contact lens out, I could never really see where the camera lens was. This always resulted in repeated comments from the technician to focus on the camera lens... ugggghhhh. To give you an idea of how frustrating this was, with the new system, they can take a picture of my cornea within a minute. With the old system, this process could take up to ten minutes.

From what I understand, the light from the concentric light rings hits the cornea and then is reflected back into the camera lens. How the light is directed back into the lens creates the topographical map. If the cornea being photographed has an irregular shape, or surface distortions (i.e. Scarring), the light is reflected back at angles that deviate from normal. The more irregularities, the more severe the topographical map. To better understand, a normal person's cornea would produce a map that was predominately black and blue, with some spikes into the yellow and red. As you can see from the images, my topographical maps are predominately red and white.

Oh, and yes, they did murder my name on the maps!