A cloudy cornea is a loss of transparency of the cornea.

Corneal opacification; Corneal edema

The cornea is normally a nearly invisible, clear structure covering the iris of the eye. Its two purposes are to transmit and focus the light entering the eye.

Causes of cloudy cornea include:

• Chemical burns to the cornea
• Herpetic keratoconjunctivitis (a form of conjunctivitis caused by herpes simplex)
• Infectious diseases
• Poor nutrition
• River blindness (onchocerciasis -- an infection common in parts of Africa)
• Several rare inherited diseases involving abnormal metabolism
• Sjogren syndrome
• Trachoma
• Trauma
• Vitamin A deficiency

Clouding leads to varying degrees of vision loss.

Consult your health care provider. There is no appropriate home care.

Contact your health care provider if:

• The outer surface of the eye appears cloudy
• You have trouble with your vision

Note: It is appropriate to see an ophthalmologist for vision or eye problems. However, your primary health care provider may also be involved if a whole-body (systemic) disease is suspected.

The health care provider will examine your eyes and ask questions about your medical history.

Questions may include:

• Did the cornea become cloudy quickly, or did it develop slowly?
• When did you first notice this?
• Does it affect both eyes?
• Is there any history of injury to the eye?
• What other symptoms do you have?
• Do you have any trouble with your vision?
• If so, what type (blurring, reduced vision, or other) and how much?

Tests may include:

• Biopsy of lid tissue
• Ophthalmoscopy
• Special photographs to measure the cells of the cornea
• Standard eye exam
• Ultrasound to measure corneal thickness

Crouch ER Jr, Crouch ER, Grant T. Ophthalmology. In: Rakel RE. Textbook of Family Medicine. 7th ed. Philadelphia, Pa: Saunders Elsevier; 2007:chap 53.

Sharma R, Brunette DD. Ophthalmology. In: Marx JA, ed. Rosen’s Emergency Medicine: Concepts and Clinical Practice. 7th ed. Philadelphia, Pa: Mosby Elsevier; 2009:chap 69.

Newlin AC, Wadia H, Sugar J. Corneal and external eye manifestations of systemic disease. In: Yanoff M, Duker JS, eds. Ophthalmology. 3rd ed. St. Louis, Mo: Mosby Elsevier; 2008:chap 4.25.