Astigmatism

Astigmatism is a general inability of the eye to focus clearly at any distance because the curvature of the cornea is not symmetrical. Instead of being spherical, the cornea has more curvature in one meridian than the other. In other words, the eye's main focusing element has two curvatures, shaped like a football instead of a basketball.

Nobody has a perfectly symmetrical cornea, but the distortion is so slight in most eyes that it does not significantly affect vision. However, possessing more than a slight degree of astigmatism can be a major refractive problem. Astigmatism is often combined with myopia and hyperopia.

This illustration shows only one of the many possible variations of astigmatism.

Common Eye
Diseases & Disorders:

Astigmatism

Chalazion

Corneal Disease &
Transplants

Eyelid Margin Disease
including Blepharitis

Glaucoma Types &
Testing

Herpes Simplex
Eye Disease

Hyperopia
(Farsightedness)

Macular Degeneration

Posterior Capsulotomy

Tearing in Adults

Bullous Keratopathy

Conjunctivitis

Diabetic Retinopathy

Fuchs' Cornial
Dystrophy

Glaucoma Treatment

Herpes Zoster

Keratoconus

Ocular Nutrition

Presbyopia

Thyroid Eye Disorders

Cataracts

Corneal Abrasion &
Erosion

Dry Eye

Glaucoma Causes &
Symptoms

Glaucoma
Laser Iridotomy

How the Eye Works

Myopia
(Nearsightedness)

Ocular Rosacea

Pterygium &
Pinguecula

Uveitis