๐๏ธ Chemosis (Conjunctival oedema) โ Causes & Management
๐ง Chemosis = swelling/oedema of the conjunctiva (often looks like โjellyโ or ballooning around the cornea).
Pathophysiology is usually either โ vascular permeability (allergy/inflammation/infection) or venous/lymphatic congestion
(orbital pressure, thyroid eye disease, impaired venous drainage). The key clinical skill is spotting the few dangerous causes
where chemosis is a marker of orbital pathology rather than simple conjunctivitis.
โ
First assessment (always)
- ๐ Check vision (acuity), pupils (RAPD), and pain level.
- ๐ Look for proptosis, reduced eye movements, diplopia, corneal exposure, photophobia.
- ๐ก๏ธ Ask about fever, sinus symptoms, trauma/surgery, contact lenses, anaphylaxis symptoms.
- ๐งช If discharge: watery vs mucopurulent; consider fluorescein if pain/photophobia/contact lenses (corneal involvement).
๐จ Red flags (same-day urgent ophthalmology / ED)
- ๐ป Reduced visual acuity or RAPD
- ๐ Severe pain, marked photophobia, or headache
- ๐๏ธโ๐จ๏ธ Proptosis, restricted eye movements, diplopia
- ๐ก๏ธ Fever/toxicity, sinusitis + eye signs (think orbital cellulitis)
- ๐ฉธ Recent facial/orbital trauma or eye surgery (think retrobulbar haemorrhage)
- ๐งช Chemical splash / alkali injury
- ๐ฆ Copious purulent discharge + rapid swelling (think gonococcal infection)
๐งฉ Causes of chemosis
- ๐ผ Allergic conjunctivitis (itching, watery discharge, lid swelling; often bilateral)
- ๐ฆ Viral conjunctivitis (gritty, watery, contagious; pre-auricular nodes)
- ๐งซ Bacterial conjunctivitis (mucopurulent discharge, lids stuck; usually mild)
- ๐ฆ Chlamydial conjunctivitis (chronic redness/discharge; follicular changes)
- โฃ๏ธ Severe hyperacute conjunctivitis (e.g., gonococcal) โ can cause dramatic chemosis
- ๐ง Orbital cellulitis / post-septal infection (chemosis + proptosis + painful/restricted EOM)
- ๐ฉธ Trauma / post-op swelling; retrobulbar haemorrhage (time-critical vision threat)
- ๐ฆ Thyroid eye disease (exposure, lid retraction, proptosis; chemosis from congestion)
- ๐ง Venous outflow obstruction (e.g., cavernous sinus thrombosis, carotidโcavernous fistula, SVC obstruction)
- ๐ฎโ๐จ Angioedema/anaphylaxis (rapid onset lid/conjunctival swelling + systemic features)
- ๐ Exposure/lagophthalmos (dryness + conjunctival oedema, especially overnight)
๐ Management (practical approach)
1) If red flags โ urgent escalation
- ๐ Same-day ophthalmology/ED if any red flags (vision threat/orbital disease).
- ๐ง Suspected orbital cellulitis/CST: treat as emergency (IV antibiotics + imaging per local pathway).
- ๐ฉธ Suspected retrobulbar haemorrhage: emergency decompression pathway (do not delay).
- ๐งช Chemical injury: immediate irrigation + urgent ophthalmology.
2) If uncomplicated (no red flags) โ treat the common causes
๐ผ Allergic chemosis
- ๐ง Cold compresses; avoid rubbing (rubbing worsens mast-cell mediator release).
- ๐ง Lubricants (preservative-free artificial tears) regularly.
- ๐งช Topical antihistamine/mast-cell stabiliser drops (e.g., olopatadine/cromoglicate depending on local formulary).
- ๐ Oral non-sedating antihistamine if systemic allergy symptoms.
- ๐งโโ๏ธ If severe/persistent: consider short supervised course topical steroid only with ophthalmology input (risk of HSV/glaucoma).
๐ฆ Viral conjunctivitis
- ๐ง Lubricants + cold compresses; hygiene advice (handwashing, avoid sharing towels).
- ๐ซ Avoid routine antibiotics (usually self-limiting).
- ๐ฉ If significant photophobia/pain or reduced vision: consider keratitis โ urgent eye review.
๐งซ Mild bacterial conjunctivitis
- ๐งผ Lid hygiene, warm compress if crusting.
- ๐ Consider topical antibiotic if marked purulence, contact-lens wearer, or not improving (local formulary e.g., chloramphenicol).
- ๐งด Stop contact lenses until fully resolved; replace lenses/case to prevent reinfection.
๐ฆ Chlamydial / hyperacute (gonococcal) suspicion
- ๐ Same-day sexual health/ophthalmology advice.
- ๐ Gonococcal eye infection is an emergency (systemic therapy + urgent ophthalmology; corneal perforation risk).
๐ฆ Thyroid eye disease / exposure-related chemosis
- ๐ง Aggressive lubrication (drops by day, ointment at night), consider taping lids closed overnight if exposure.
- ๐ญ Smoking cessation (major modifiable risk factor for TED severity).
- ๐งโโ๏ธ Refer to ophthalmology/TED service if proptosis, diplopia, pain, or corneal exposure.
๐ Patient advice
- โ
Seek urgent help if vision worsens, pain increases, new diplopia, or swelling rapidly progresses.
- ๐งผ Avoid rubbing; wash hands; donโt share towels/makeup.
- ๐ Avoid contact lenses until symptoms fully settle.
๐ Clinical pearl: chemosis is a sign, not a diagnosis. The โbig dividerโ is whether there are features of
orbital disease or vision compromise. If the eye is painful, proptosed, movement-limited, febrile, or vision is reduced,
treat it as urgent until proven otherwise.