What is Astigmatism
Eyestrain
One of the most common diagnoses against the astignatismo eyestrain. What is astigmatism? Why produce symptoms such as headaches or burning sensation in your eyes? Then the experts tell us that is astigmatism and what are its main symptoms.
The cornea, lens is in front of the eye that receives and “compresses” the images so that they reach the retina clear, is shaped like a hemisphere and is almost perfect transparency. In fact, usually have a radius of curvature larger and a smaller. To be more specific we could say that football has all the same bend radius while a rugby ball has a radius of curvature than the horizontal vertical. When this happens in the cornea, there is astigmatism. It can range from very mild to quite pronounce.
Two different types of astigmatism
Pronounced astigmatism is easily detected because it produces reduced vision. Once detected the presence of high astigmatism, ie greater than 3 diopters lenses, it is important to complete the studies with the topography, a map of the corneal surface, which can diagnose whether the astigmatism is stable or progressive astigmatism is what is more severe and in this case required special treatment.
However, small astigmatism goes unnoticed by routine examination. That is, despite having astigmatism can see all the letters of the cartel office. This little altered very little astigmatism eyesight and usually causes no problem for life or for the sport. No need to be compensated with the use of glasses. But if a person spends much time using the view, for example, reading or against the computer, appear now to recognize as “visual fatigue.”