Actinic Health Dictionary

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Actinic: From 1 Different Sources

Pertaining to changes caused by the ultraviolet rays in sunlight, as in actinic dermatitis (inflammation of the skin) and actinic keratosis (roughness and thickening of the skin).
Health Source: BMA Medical Dictionary
Author: The British Medical Association

Keratosis

Also known as actinic keratosis; a rough, scaly area on exposed skin caused by chronic solar damage from exposure to sun. The face and backs of the hands are most commonly affected. (See also MELANOMA; PHOTODERMATOSES.) CRYOTHERAPY is e?ective, but prevention by appropriate clothing and sun-blocking creams is a better strategy.... keratosis

Lentigo

Lentigines (freckles) are brown MACULES varying in diameter from 1–10 mm or more. Simple lentigines arise in childhood, not necessarily on exposed areas. They may also occur on the lips and are harmless and usually very small. Solar or actinic lentigines are common on the face, neck and backs of the hands in older people and re?ect the total cumulative lifetime’s exposure to sunlight.... lentigo

Cornea

The transparent thin-walled dome that forms the front of the eyeball. The cornea is joined at its circumference to the sclera (white of the eye); the black pupil and the coloured iris are visible beneath it. The main functions of the cornea are to help focus light-rays on to the retina at the back of the eye and to protect the front of the eye. It is kept moist by tears produced by the lacrimal gland and the mucus- and fluid-secreting cells in the eyelids and conjunctiva. cornea, disorders of Injuries or diseases affecting the cornea, the outer shell of the eyeball. Injuries include corneal abrasions, which sometimes become infected and progress to a corneal ulcer. Penetrating corneal injuries can cause scarring, which may lead to impairment of vision. Chemical injuries can result from contact with a corrosive substance and require immediate flushing of the eye with water.

In actinic keratopathy, the outer layer of the cornea is damaged by ultraviolet light. In exposure keratopathy, damage is due to reduced protection by the tear film and blink reflex. The cornea can also be infected by viruses, bacteria, and fungi, the herpes simplex virus being especially dangerous. True inflammation of the cornea (called keratitis) is uncommon as the cornea contains no blood vessels.

Other disorders include: keratomalacia as a result of vitamin A deficiency; keratoconjunctivitis sicca (dry eye); corneal dystrophies such as keratoconus; and oedema, in which fluid builds up in the cornea and impairs vision.

Rare congenital defects include microcornea (smaller cornea than normal) or megalocornea (bigger than normal) and buphthalmos, or “ox-eye’’, in which the entire eyeball is distended as a result of glaucoma.

Degenerative conditions of the cornea such as calcium deposition, thinning, and spontaneous ulceration occur mainly in the elderly, and are more common in previously damaged eyes.... cornea

Keratopathy

A general term used to describe a variety of disorders of the cornea.

Actinic keratopathy is a painful condition in which the outer layer of the cornea is damaged by ultraviolet light.

Exposure keratopathy is corneal damage due to loss of the protection afforded by the tear film and blink reflex.

It may occur in conditions in which the eyelids inadequately cover the cornea, including severe exophthalmos, facial palsy, and ectropion.... keratopathy

Snow-blindness

A common name for actinic keratopathy.... snow-blindness

Sunlight, Adverse Effects Of

Problems resulting from overexposure to sunlight. Fair-skinned people are more susceptible. Short-term overexposure causes sunburn and, in intense heat, can result in heat exhaustion or heatstroke. Repeated overexposure over a long period can cause premature aging of the skin and solar keratoses. It increases the risk of skin cancer. Protection of the skin with sunscreens helps to prevent sun damage. Photosensitivity is an abnormal sensitivity to sunlight, resulting in a rash.

Exposure to sunlight can affect the eyes, causing irritation of the conjunctiva, actinic keratopathy, or pterygium.

Good sunglasses help to prevent eye problems.... sunlight, adverse effects of

Diclofenac

n. an anti-inflammatory drug (see NSAID) used to relieve joint pain in osteoarthritis, rheumatoid arthritis, ankylosing spondylitis, acute gout, and actinic *keratosis, and also for pain relief after surgery. Possible side-effects include abdominal pain, nausea, and diarrhoea; gastric ulceration can be prevented by administering diclofenac in combination with *misoprostol.... diclofenac

Imiquimod

n. a drug used for treating anogenital warts, superficial basal cell carcinoma, and actinic *keratosis.... imiquimod

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