Astigmatism
Astigmatism is an uneven or irregular curvature of the cornea or lens, which results in blurred or distorted vision. Other symptoms of astigmatism include the need to squint, eye strain from squinting, headaches and eye fatigue.
In reality, most people have some degree of astigmatism, which is usually present at birth and is believed to be hereditary. In minor cases, treatment may not be required but is certainly beneficial. Moderate to severe astigmatism can be treated with corrective eyewear or LASIK surgery.