Astigmatism

This condition occurs when the cornea is slightly irregular in shape and prevents light from focusing properly on the retina. Astigmatism makes vision blurred at all distances. Most people have a certain degree of astigmatism but it is usually very mild and does not cause any problems. In other cases it can cause eyestrain and headaches. In the more severe cases the vision will be blurred.

As with most vision conditions, astigmatism can be corrected using glasses or contact lenses. Another method to cure this condition is Corneal Modification.

A*stig"ma*tism (#), n. [Gr. priv. + , , a prick of a pointed instrument, a spot, fr. to prick: cf. F. astigmatisme.] Med. & Opt.

A defect of the eye or of a lens, in consequence of which the rays derived from one point are not brought to a single focal point, thus causing imperfect images or indistictness of vision.

⇒ The term is applied especially to the defect causing images of lines having a certain direction to be indistinct, or imperfectly seen, while those of lines transverse to the former are distinct, or clearly seen.

 

© Webster 1913.