Reddish eye

Red eye (medicine)
Subconjunctival hemorrhage causing red coloration as result of ruptured blood vessel in the eye.
Classification and external resources
Specialty	ophthalmology
ICD-10	H57.9
ICD-9-CM	379.93
DiseasesDB	18665
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A red eye is a non-specific term to describe an eye that appears red due to illness or injury. The term usually refers to injection and prominence of the superficial blood vessels of the conjunctiva, or sclera, which may be caused by disorders of these or adjacent structures. Conjunctivitis and subconjunctival hemorrhage are two of the less serious but more common causes.

Management includes assessing whether emergency action (including referral) is needed, or whether treatment can be accomplished without additional resources.

Slit lamp examination is invaluable in diagnosis but initial assessment can be performed using a careful history, testing vision (visual acuity), and carrying out a penlight examination.

Of the many causes, conjunctivitis is the most common. Others include:
Usually nonurgent

Usually urgent

Particular signs and symptoms may indicate that the cause is serious and requires immediate attention.

Six such signs are:

The most useful is a smaller pupil in the red eye than none red eye and sensitivity to bright lights.

A reduction in visual acuity in a 'red eye' is indicative of serious ocular disease, such as keratitis, iridocyclitis, and glaucoma, and never occurs in simple conjunctivitis without accompanying corneal involvement.

Ciliary flush is usually present in eyes with corneal inflammation, iridocyclitis or acute glaucoma, though not simple conjunctivitis. A ciliary flush is a ring of red or violet spreading out from around the cornea of the eye.

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