Corneal topography is a diagnostic technique that allows the cornea to be fully analyzed. In this way, it is possible to detect corneal alterations, as well as to adjust specific contact lenses. In addition, it is an essential technique for refractive surgeries.
DIAGNOSIS OF CORNEAL PATHOLOGIES
Through corneal topography it is possible to diagnose, efficiently and quickly, some of the most common alterations of the cornea. Irregular astigmatisms, as well as keratoconus are part of these pathologies. In addition, it allows the professional to have a specific monitoring of this type of alterations.
On the other hand, corneal topography is essential in corneal transplants or keratoplasties. This technique is used before and after surgery. It will then be used to monitor patients.
REFRACTIVE SURGERIES
Before submitting a patient to any refractive surgery it is necessary to perform a comprehensive study. One of the most important tests of this preoperative study is undoubtedly the corneal topography because it provides invaluable information to determine whether or not the treatment is appropriate and even the most appropriate type of surgery in each case. After the operation, the surgeon returns to the topographer to examine the cornea.
CONTACT LENSES ADAPTATION
There are many reasons why contact lenses must adapt properly to the surface of the eye. To do this, knowing in detail the surface of the cornea is a very important value. Thanks to this ophthalmological technique, the professional has a lot of information that will allow the lens to adapt properly to the patient's eye.
To perform the test, the use of a corneal topographer is essential. This instrument is connected to a highly accurate computer system. The examination is completely painless for the patient, as well as very fast. You simply have to sit in front of the equipment, which will project a series of concentric colored rings on the cornea and measure the way in which these are reflected on it. The most advanced systems are prepared to detect any type of corneal irregularity in the patient's eye, showing data such as:
Corneal topographers can be classified in two different ways:
Of Elevation or Specular Reflection
- Specular reflection topographers: these are usually found in optics. They are the ones used by the optometrist to be able to adapt the contact lenses to the cornea of each patient. In addition, they provide very valuable information on the most common corneal alterations.
- Elevation: these corneal topographers are much more accurate than the previous ones. They are the ones that are usually found in ophthalmology clinics that perform refractive surgery operations. In addition to the usual information from these devices, they also provide data on the thickness of the cornea.
Wide or Narrow Cone
Wide cone surveyors are able to study a more limited area of the ocular surface, but their handling is much easier. For their part, those surveyors with a narrow cone provide information from a wider area, but handling them requires greater precision.
The corneal topographer consists of a computer connected to an instrument that projects concentric colored rings (Placido disk) on the cornea. The patient is seated and rests the chin on a chin rest while these rings are projected and centered on the cornea.