Red eye (medicine)
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2008-07-06T19:29:48Z
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{{otheruses|Red eye}}
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DiseasesDB = 18665 |
ICD10 = {{ICD10|H|57|9|h|55}} |
ICD9 = {{ICD9|379.93}} |
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In [[medicine]], '''''red eye''''' is a non-specific term to describe an [[eye]] that appears [[red]] due to illness, injury, or some other condition. "Conjunctival injection" and "bloodshot eyes" are two forms of red eye.
Since it is a common affliction, it is unsurprising that [[primary care]] [[Physician|doctor]]s often deal with [[patient]]s with red eyes in their practices.
The goal of the primary care doctor when presented with a red eye is to assess whether it is an [[medical emergency|emergency]] in need of referral and immediate action, or instead a benign condition that can be managed easily and effectively.
Red eye usually refers to [[hyperemia]] of the superficial [[blood vessel]]s of the [[conjunctiva]], [[sclera]] or [[episclera]], and may be caused by [[disease]]s or disorders of these structures or adjacent structures that may affect them directly or indirectly.
==Causes==
There are many causes of a red eye including [[conjunctivitis]], [[blepharitis]], acute [[glaucoma]], [[eye injury|injury]], [[subconjunctival hemorrhage]], inflamed [[pterygium]], inflamed [[pinguecula]], [[dry eye syndrome]], and drug use including cannabis.
==Investigation==
Some [[sign (medicine)|sign]]s and [[symptom]]s of red eye represent warnings that the underlying cause is serious and requires immediate attention.
The [[person]] conducting a thorough [[eye examination]] should be attentive to the warning signs and symptoms during the eye exam.
There are six danger signs: conjunctival injection, ciliary flush (circumcorneal injection), corneal edema or opacities, corneal staining, abnormal pupil size, and abnormal intraocular pressure.
===Visual acuity===
''Reduced [[visual acuity]]'' is indicative of serious ocular disease, such as [[cornea]]l inflammation, [[iridocyclitis]], and [[glaucoma]], and never occurs in simple [[conjunctivitis]] without concurrent corneal involvement.
===Ciliary flush===
''[[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 (color)|violet]] around the [[cornea]] of the eye.
===Corneal opacification===
Corneal opacities always indicate that a serious disease process is in progress.
Opacification may be detected using an [[ophthalmoscope]] or, in more obvious cases, with a pen light.
These opacities may be keratic, haze-like (usually from corneal [[edema]]), or they may be localized such as with [[ulcer]]ated corneas or those affected by [[keratitis]].
===Corneal epithelial disruption===
Corneal epithelial disruptions may be detected with [[fluorescein]] staining of the eye, and careful observation with [[cobalt]]-[[blue]] [[light]].
Corneal epithelial disruptions would stain [[green]], which represents some injury of the corneal epithelium.
These types of disruptions may be due to [[corneal inflammation]]s or [[physical trauma]] to the cornea.
===Pupillary abnormalities===
An eye with iridocyclitis would have one [[pupil]] that is smaller than the other, which is caused by a [[reflex]] [[muscle]] [[spasm]] of the [[Iris (anatomy)|iris]] sphincter muscle.
As is the general rule, conjunctivitis does not affect the pupils.
With acute angle-closure glaucoma, the pupil would be partially dilated and oval.
===Shallow anterior chamber depth===
Shallow anterior chamber depth usually indicates some problem.
If the eye is red, anterior chamber depth may indicate acute [[glaucoma]], which requires immediate attention.
===Abnormal intraocular pressure===
Intraocular pressure should be measured as part of the routine [[eye examination]].
It is usually affected only by iridocyclitis or acute-closure glaucoma, but not by relatively benign conditions.
In iritis and traumatic perforating ocular injuries, pressure is usually low.
===Proptosis===
[[Proptosis]], or forward displacement of the globe, may be caused by an [[infection]] of the [[orbit (anatomy)|orbit]], or a cavernous sinus disease.
Most commonly, chronic proptosis is caused by [[thyroid]] diseases such as [[Graves disease]].
==Important warning symptoms==
There are three main danger symptoms in a red eye: reduced visual acuity, severe ocular pain, and photophobia (light sensitivity).
===Blurry vision===
Blurry vision often indicates serious ocular disease.
If the blurriness improves with [[blink]]ing, it suggests ocular surface discharge of some variety.
===Severe pain===
Those suffering from [[conjunctivitis]] may report mild irritation or scratchiness, but never extreme [[pain]].
Severe pain is an indicator of [[keratitis]], corneal ulceration, [[iridocyclitis]], or acute [[glaucoma]].
===Photophobia===
[[Photophobia]] (fear of [[light]]) is most characteristic of [[iritis]], but may also depend on acute [[glaucoma]].
===Coloured halos===
Coloured [[Halo (optical phenomenon)|halo]]s are an indication of [[corneal edema]], and are a warning that acute glaucoma may be present.
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==Other signs==
===Conjunctival hyperemia===
===Discharge===
===Preauricular lymph node enlargement===
==Other symptoms==
===Exudation===
===Itching===
=Management=
=References=
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==See also==
*Physician education on '''The Diagnosis and Treatment of Bacterial Conjunctivitis in Pediatric Patients''' at http://www.medscape.com/viewarticle/575864_6
*[[List of eye diseases and disorders]]
{{Eye pathology}}
[[Category:Ophthalmology]]
[[Category:Emergency medicine]]
[[it:Occhi rossi]]
[[ja:充血]]