Red eye is the characteristic sign of ocular inflammation and one of the most common symptoms in ophthalmology. In fact, inflammation of almost any eye structure, including the lacrimal glands, eyelids or altered tear film, can cause red eyes.
In the first instance, eye redness is usually managed by treating physicians, who then refer patients to an ophthalmologist if necessary.
What are the causes of eye redness?
The conjunctivitis is the most common cause of red eyes. Other common causes include blepharitis, corneal abrasion, foreign body, subconjunctival haemorrhage, keratitis, iritis, glaucoma, chemical burn and scleritis.
In general, viral and bacterial conjunctivitis are self-limiting conditions and the occurrence of serious complications is a rare event. To date, there is no diagnostic test that can differentiate viral from bacterial conjunctivitis, although in most cases, conjunctivitis is of viral origin. A bacterial aetiology is, in fact, usually suggested by the presence of purulent discharge.
Diagnosis
The cause of red eyes can be diagnosed through a detailed patient history and a careful examination of the eyes. The history should include questions about eye involvement (unilateral or bilateral), duration of symptoms, visual changes, severity of pain, photophobia, previous treatments, presence of allergies or systemic diseases and contact lens wear.
Diagnostic examinations, on the other hand, include evaluation of the eyelids, tear sac, pupil size, reaction to light and visual acuity.
Recognition by the treating physician of the need for urgent referral to an ophthalmologist is of paramount importance in the management of red-eye treatment: for example in cases of severe pain and/or if eye pain does not subside following topical anaesthetic therapy .
Treatment: advantages of topical steroid-antibiotic combinations
Although conjunctivitis is usually self-limiting, if it does not resolve spontaneously, the use of certain classes of topical antibiotics has been shown to improve symptoms and reduce the duration of the disease. In addition, as active conjunctivitis is best controlled with steroid-containing preparations, topical steroid/antibiotic combinations, such as dexamethasone/netilmincin combinations, are often used. Such combinations have several advantages over the use of single components, including better patient compliance, lower costs and reduced potential wash-out effect.
Bibliography:
- H Cronau et al. Diagnosis and Management of Red Eye in Primary Care. American Family Physician. January 15, 2010; Volume 81, Number 2
- F Faraldi et al. Netilmicin/dexamethasone fixed combinationin the treatment of conjunctival inflammation. Clinical Ophtalmology, 2013:7, 1239-1244
Dr. Carmelo Chines
Direttore responsabile
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