A common misconception about astigmatism is that it is a disease. It is just an irregularity in the eye – a cornea or lens that is not symmetrical – and is very easy to treat. A ‘normal’ eye’s cornea is shaped like a basketball. An eye with astigmatism is shaped more like a football. When light enters an eye with astigmatism it is refracted unevenly and blurs vision and causes an inability of the eye to focus parts of an object.
Causes and symptoms
The cause of astigmatism is usually unknown as it is not associated with any external causes. It is sometimes hereditary and present at birth. Sometimes, it can be caused by keratoconus – a condition in which the cornea becomes thin and cone shaped, bulging out and distorting vision. Keratoconus is treatable, and patients can usually avoid a cornea transplant. Some people spontaneously develop astigmatism. Astigmatism can also be caused by abnormalities inside the eye and be easily treated with eyeglasses, contact lenses, or surgery.
You should consult a doctor if you have:
- Blurring of small print, difficulty reading
- Double vision
- Inability to see both near and distant without squinting
Children with vision problems, such as astigmatism may experience:
- Difficulty focusing on printed words and lines
- Eye strain, tired eyes, or headaches
How common is it?
Astigmatism is very common, as most people have some degree of the condition. It is estimated that one in three people may have some form of astigmatism. A slight astigmatism doesn’t affect vision or require treatment.
How is it corrected and am I still a candidate for LASIK?
Astigmatism can be corrected with glasses, contact lenses, or LASIK surgery. LASIK addresses astigmatism by reshaping the cornea to correct the way light hits the eye, shaping it more like a basketball than a football. Glasses and contact lenses will temporarily fix astigmatism while they are being worn, but LASIK will alter the shape of your eye and give you the vision you’ve been missing.