What is a corneal topography?

 

Corneal topography is an eye control that is useful to map the anterior surface of the cornea which is responsible for about 2/3 of the refractive capacity of the organ itself and to know its shape.

 

 

What's that for?

 

Corneal topography allows us to know the curvature of the anterior surface of the cornea. The exam provides a coloured mapping and each color corresponds to a radius of curvature. Cold colours like blue indicate flatter points, that is those which have a greater radius of curvature, while warm colours like red indicate a greater curvature, that is a smaller radius of curvature.

A standard topography shows an imagine with warmer colours in the middle, while in the more peripheral areas colder colours indicate flatter areas.

 

 

Image source: http://eyewiki.aao.org/Corneal_topography

 

 

How to do a corneal topography?

 

 

With the use of a corneal topographer.
This one projects on the cornea several concentric rings and in a second moment reads the reflection on the image on the organ.
At this point a computer elaborates this image reflected on the cornea and calculates the curvature by studying the distorsion that rings have suffered.
The corneal topography execution is not invasive and does not require the use of eye drops.
If you wear contact lenses remember that corneal topography can only be performed at least 24 hours after the use of soft contact lenses or 48 hours for rigid contact lenses.

 

 

When to do a corneal topography?

 

 

It's advisable to do a corneal topography when suffering from keratoconus (eye desease:corneal deformation),before a refractive surgery to understand which points are involved and how to operate with laser and before a corneal transplant, in contactology for an evaluation of the effects of contact lenses on the cornea, etc.

Ottica chiodi performs free corneal topographies as preliminary check-up and always recommends an in-depth visit by the ophthalmologist.