Related Subjects:
|Episcleritis
|Scleritis
|Assessing a Red eye
|Acute Angle Closure Glaucoma
|Allergic and Infective Conjunctivitis
|Anterior and Posterior Uveitis
|Herpes simplex keratitis (HSK)
|Acute Blepharitis
|Corneal Abrasion
๐ Intravitreal injections (for AMD, diabetic macular oedema, retinal vein occlusion) have revolutionised retinal care, preventing blindness in thousands.
โ ๏ธ Rare but devastating complication: endophthalmitis.
๐ Any patient with pain, redness, or vision loss post-injection = same-day urgent ophthalmology review.
๐๏ธ Acute Red Eye โ Introduction
- โRed eyeโ is a symptom, not a diagnosis.
- Causes range from benign (conjunctivitis) โ sight-threatening (acute glaucoma, keratitis, uveitis, endophthalmitis).
- โ ๏ธ Red, painful eye + โ vision = ophthalmic emergency until proven otherwise.
๐ Causes of Acute Red Eye
- ๐๏ธ Conjunctivitis โ bacterial (purulent), viral (watery, contagious), allergic (itchy, chemosis).
- ๐ฆ Corneal disease: abrasion, ulcer, infective keratitis โ pain + photophobia.
- ๐ช Foreign body: irritation, tearing, fluorescein uptake with abrasion.
- ๐ฅ Uveitis (iritis): deep pain, photophobia, ciliary flush, constricted pupil.
- ๐จ Acute angle-closure glaucoma: severe pain, haloes, headache, N/V, mid-dilated fixed pupil, corneal haze.
- ๐ฟ Blepharitis: lid margin inflammation, gritty sensation.
- ๐ง Dry eye syndrome: chronic irritation, worse with screen use.
- โก Endophthalmitis: post-op/injection, severe pain + โ vision. Sight-threatening.
- โข๏ธ Chemical injury: irrigate immediately before full history/exam.
๐งพ Key Symptoms
- ๐๏ธ Redness (sectoral vs diffuse).
- ๐ Pain (mild โ severe boring pain).
- ๐ง Discharge (watery vs mucopurulent vs stringy).
- ๐ Photophobia (suggests corneal/uveal pathology).
- ๐ Blurred vision or vision loss โ red flag.
- ๐ช Foreign body sensation.
๐ฉบ Diagnostic Approach
- History: Onset, discharge, photophobia, vision changes, trauma, CL wear, autoimmune disease.
- Exam: Visual acuity first, pupils, corneal staining (fluorescein), slit-lamp, IOP if glaucoma suspected.
- Phenylephrine blanching: Episcleritis (blanches) vs scleritis (persists).
- Microbiology: Swab in purulent conjunctivitis or corneal ulcer.
๐จ Complications if Untreated
- ๐ฆ Corneal ulceration โ scarring โ blindness.
- ๐ Uveitis sequelae: synechiae, glaucoma, cataract.
- โก Endophthalmitis โ rapid, irreversible sight loss.
๐ Treatment by Condition
- ๐๏ธ Bacterial conjunctivitis: Chloramphenicol drops, hygiene, avoid CL use. Treat high-risk groups.
- ๐ฆ Viral conjunctivitis: Supportive (lubricants, cold compress). Highly contagious โ hygiene + avoid school/work.
- ๐ผ Allergic conjunctivitis: Topical antihistamines/mast-cell stabilisers, cold compress, oral antihistamines if systemic.
- ๐ช Corneal abrasion: Lubricants + prophylactic topical abx. No patch if CL-related (risk of Pseudomonas).
- ๐ช Foreign body: Remove at slit-lamp, topical abx, evert lid, follow up if rust ring/central cornea.
- ๐ฅ Uveitis: Topical steroids + cycloplegics (only under ophthalmology). Screen for systemic cause (HLA-B27, sarcoid, IBD).
- ๐จ Acute angle-closure glaucoma: IV acetazolamide + topical ฮฒ-blocker/pilocarpine. Urgent iridotomy.
- โก Endophthalmitis: Emergency vitreous tap + intravitreal abx. Any post-op/post-injection red eye = same-day referral.
- ๐ฟ Blepharitis: Lid hygiene, warm compress, lubricants. Chronic course, linked with rosacea/seb derm.
- ๐ง Dry eye: Lubricants, punctal plugs if severe. Exacerbated by age, antihistamines, SSRIs, screens.
๐ก Teaching Pearls
- ๐ Visual acuity must always be checked first - even before slit-lamp.
- โฑ๏ธ Time-critical: Angle-closure and endophthalmitis are true emergencies.
- ๐งช Fluorescein staining is invaluable in corneal disease.
- ๐ง Think systemic: Uveitis often linked with autoimmune disease.
- ๐
Never patch a contact-lens abrasion โ risk of Pseudomonas keratitis.
