Astigmatism is a common condition, which is very mild in nature. It is an imperfection of the curvature of the eyes which may cause blurred and imperfect vision. In astigmatism, the eye structure is a bit deformed, preventing the eyes from generating normal images.
The cornea or the surface of the eyes is curved and possesses a certain curvature. Normally, the lens inside the eye also has the same curvature. However in case the cornea and the lens have different curvatures, even to the slightest of degrees from one another, the eye develops impaired vision. Sometimes, instead of having different curvatures, either the cornea or the lens may develop flat or steep areas on the surface and this causes the person to experience impaired vision or astigmatism.
Astigmatism may blur your vision completely or only affect them at specific distances, depending on the impairment of the cornea or lens surface. In most cases, astigmatism occurs due to birth defects. It is also usually found in combination with nearsightedness or farsightedness. The condition is usually completely treatable using corrective lenses or surgery. However, if the case is mild, no treatment may be necessary.