Some Causes of Red Eye
Cause | Suggestive Findings | Diagnostic Approach |
|---|---|---|
Conjunctival disorders and episcleritis* | ||
Bilateral, prominent itching, possibly conjunctival bulging (chemosis) Known allergies or other features of allergies (eg, seasonal recurrences, rhinorrhea) | History and physical examination, including ophthalmic examination if the diagnosis is unclear or vision loss present‡ | |
Chemical (irritant) conjunctivitis | Exposure to potential irritants (eg, dust, smoke, ammonia, chlorine, phosgene) | History and physical examination, including ophthalmic examination if the diagnosis is unclear or vision loss present‡ |
Unilateral focal redness, mild irritation, minimal lacrimation | History and physical examination, including ophthalmic examination if the diagnosis is unclear or vision loss present‡ | |
Infectious conjunctivitis | Scratchy sensation, photosensitivity Sometimes mucopurulent discharge, eyelid edema, or papillae on tarsal conjunctiva | History and physical examination, including ophthalmic examination if the diagnosis is unclear or vision loss present‡ Ensure fastidious hand hygiene and cleaning of examination equipment to prevent cross-contamination |
Unilateral, asymptomatic focal red patch or confluent redness Possibly prior trauma or Valsalva maneuver | History and physical examination‡ | |
Intense itching, stringy discharge Usually preadolescent or adolescent males Other atopic disorders Waxing in spring and waning in winter | History and physical examination, including ophthalmic examination if the diagnosis is unclear or vision loss present‡ | |
Corneal disorders† | ||
Contact lens keratitis | Prolonged wearing of contact lenses, lacrimation, corneal edema | History and physical examination, including ophthalmic examination if the diagnosis is unclear or vision loss present‡ |
Onset after injury (but this history may be inapparent in infants and young children) Foreign body sensation | History and physical examination, including ophthalmic examination if the diagnosis is unclear or vision loss present‡ | |
Often grayish opacity on the cornea, followed by a visible crater Possibly a history of sleeping with contact lenses | Ophthalmic evaluation‡ Culture of ulcer (scrapings done by an ophthalmologist) | |
Epidemic keratoconjunctivitis (adenoviral conjunctivitis with keratitis), if moderate or severe | Copious watery discharge Often eyelid edema, preauricular lymphadenopathy, chemosis (bulging of the conjunctiva) Occasionally severe temporary loss of vision | History and physical examination, including ophthalmic examination if the diagnosis is unclear or vision loss present‡ |
Onset after conjunctivitis, blisters on eyelid Unilateral | Ophthalmic evaluation‡ Viral culture if diagnosis is unclear | |
Unilateral vesicles and crusts on an erythematous base in a V1 distribution, sometimes affecting the tip of the nose Eyelid edema Red eye May be associated with uveitis Possibly severe pain | Ophthalmic evaluation‡ Viral culture if diagnosis is unclear | |
Other disorders | ||
Severe ocular ache Headache, nausea, vomiting, halos around lights Hazy cornea (caused by edema), marked conjunctival erythema Decreased visual acuity Intraocular pressure usually > 40 mm Hg | Tonometry and gonioscopy by ophthalmologist | |
Ocular ache, photophobia Ciliary flush (redness most concentrated and often confluent around the cornea) Often a risk factor (eg, autoimmune disorder, blunt trauma within previous few days) Possibly decreased visual acuity or pus in anterior chamber (hypopyon) Cells and flare on slit-lamp examination | Ophthalmic evaluation‡ | |
Severe pain, often described as boring Photophobia, lacrimation Red or violaceous patches under bulbar conjunctiva Scleral edema Tenderness of globe when palpated Often history of autoimmune disorder | Ophthalmic evaluation‡ Further testing by or in conjunction with an ophthalmologist | |
* Unless otherwise described, usually characterized by itching or scratchy sensation, lacrimation, diffuse redness, and often photosensitivity, but no change in vision and absence of pain and true photophobia. | ||
† Unless otherwise described, usually characterized by lacrimation, pain, and true photophobia. Vision affected if the lesion involves the visual axis. | ||
NSAIDs = nonsteroidal anti-inflammatory drugs; V1= ophthalmic division of the trigeminal nerve. | ||