Astigmatism is a refractive defect in which the image is formed in two different focus areas. This is due to the fact that the curvature of the cornea or crystalline is not symmetrical. Many times it is also accompanied by hyperopia or myopia.
Typical symptoms are blurred vision at all distances, fatigue or headache. When astigmatism is low, there is usually no discomfort, but in times of much work or stress, then it can manifest itself in a form of discomfort and fluctuating vision.
Its amount is usually quite invariable during life. It does not usually increase. People wearing glasses usually gradually increase their prescription in order to avoid moving of the floor. In young adolescents who show high increasing astigmatism, they should be suspected of keratoconus (the cornea is pumped in a very marked way). In elderly peopel, when it begins to increase, it is usually related to the appearance of cataracts.
Astigmatism is usually compensated with glasses, contact lenses, ortho-k (they are special contact lenses that flatten the cornea) or surgery.