Causes of red eye

Question 1

Acute glaucoma

Question 2

Anterior uveitis

Answer 2

Anterior uveitis is inflammation of the iris and ciliary body and occurs most commonly in young, white males and is idiopathic

Inflammation of the uveal tract ± inflammation of neighbouring structures e.g. retina/ vitreous

Accounts for 10% visual impairment

Anterior AKA iritis

Uveal tract = pigmented middle layer of the eye (lies between the sclera and retina

Consists of the iris, ciliary body and choroid

Classification:

Anatomical: unilateral (acute and infectious), bilateral (chronic and systemic)

Anterior uveitis (iris inflammation), intermediate uveitis (vitreous and posterior part of ciliary body), posterior uveitis (choroid inflammation), panuveitis (inflammation throughout uveal tract)

Causes:

• Inflammatory: autoimmune disease
• Infectious: esp. if immunosuppressed
• Infiltrative: neoplastic
• Trauma: common cause of anterior uveitis
• Iatrogenic
• Ischaemic
• Idiopathic

**Sarcoidosis is most common systemic disease that presents as chronic uveitis**

Presentation

• Acute: usually one eye, pain redness and photophobia, eye pain when reading, blurred vision, lacrimation, headache common
• Chronic: blurred vision and mild redness, no pain or photophobia, one symptom may predominate usually blurred vision

Examination

• Fully dilated eye examination is needed to look for posterior disease, check visual acuity, extraocular movement normal, miosis is common, aqeous looks cloudy

Investigations

• Diagnosed by hx if mild unless bilateral or granulomatous in which case futher hx needed to look for cause

Associated conditions

• Ankylosing spondylitis
• Reactive arthritis
• Ulcerative colitis, Crohn’s disease
• Behcet’s disease
• Sarcoidosis: bilateral disease may be seen

Management

• Urgent review by ophthalmology
• Cycloplegics (dilates the pupil which helps to relieve pain and photophobia) e.g. Atropine, cyclopentolate
• Steroid eye drops

Question 3

Episcleritis

Answer 3

Relatively common and benign condition involving inflammation of the superficial episcleral layer of the eye

Clasically a non-painful red eye, lacrimation and photophobia, vessels move when eye is pressed (contrast to scleritis where vessels are deep so don’t move)

50% bilateral

Simple: vascular congestion

Nodular: discrete elevated area of inflamted episclera

Investigations

Clinical diagnosis

Management

• Conservative, artificial tears, topical NSAIDs, oral NSAIDs for nodular

Lasts 7-10 days before resolving (simples), nodular is more severe and takes longer to resolve

Complications

• Involvement of ocular structures rare, complications occur due to steroid use

Associated conditions

• Crohn’s most common
• RA, polyarteritis nodosa, SLE, granulomatosis with polyangiitis

Episcleritis vs scleritis

• Episcleritis: vessels can be moved with a cotton bud and when phenylephrine applied the vessels blanch// slceritis vessels are deep so don’t move and don’t blanch
• Episcleritis is mild with no occular symtpoms// slceritis is painful
• Episcleritis may present late as usually mild// scleritis presents early as symptoms severe
• Episcleritis rarely associated with systemic symptoms// scleritis commonly associated with systemic disease

Question 4

Scleritis

Answer 4

Severe inflammation that occurs throughout entire thickness of slcera

Rare, mor common in women and older age group than episcleritis (mean age = 52yrs)

Clasically painful red eye (in comparison to episleritis which is painless)

Clinical features

• Eye pain - worse with movement
• Radiates to head, boring pain
• Wakes them at night
• Red eye
• +/- nodules or necrotic patch
• Sclera tender to palpate
• Epiphora (flow of tears not due to crying)
• Photophobia
• Gradual decrease in vision

Management

Urgent same day referral

• Necrotising can result in permanent scleral damage & visual loss
• Oral NSAIDS or oral prednisolone
• Necrotising: steroids and immunosuppression
• Scleritis tends to follow the disease course of the underlying problem

Associated conditions

Often presents with other inflammatory diseases e.g. RA most common, granulomatosis, slceritis may be the first symptom of connective tissue disease

Question 5

Conjunctivitis

Answer 5

Infectious

Conjunctivitis is the most common eye problem presenting to primary care. It is characterised by sore, red eyes associated with a sticky discharge, gritty feeling

No photophobia and visual acuity unaltered

Bacterial: purulent discharge, eyes may be stuck together in morning

Viral: serous discharge, recurrent URTI, preauricular LNs

Management:

• Normally self limiting, settles in 1-2 weeks
• Chloramphenicol is offered as drops
• Topical fusidic acid for pregnant women
• Do not wear lenses
• Do not share towels
• No need for school exclusion

Allergic

• May occur alone but often occurs with hayfever
• Features: bilateral red eye, conjunctival swelling, itch is prominent, eyelids may be swollen, hx of atopy, may be seasonal or perennial

Management: first line = topical or systemic antihistamines, second line = topical mast cell stabilisers e.g. sodium cormoglicate

Question 6

Keratitis

Answer 6

Inflammation of the cornea

Moderate to intense pain, impaired eyesight, photophobia, gritty sensation

Causes

• Viral: herpes simplex keratitis = viral infection of the cornea, leaves a classical dendritic ulcer on the eye. Herpes zoster keratitis
• Bacterial: bacterial infection of the cornea due to wearing lenses, mainly staph aureus
• Amoebic: acanthamoebic keratitis ⚠️ serious infection that affects lense wearers

Management

• Depends on cause, often needs anti-bacterial/ viral/ fungal therapy

Question 7

Corneal abrasion

Answer 7

Small scartch on cornea, usually due to trauma e.g. fingernail, grit in eye, lenses getting stuck when you sleep in them…

Most heal in 24-72hrs

Causes pain, redness, light sensitivity, feels like foreign body in eye, tear production, squinting

Can predispose to keratitis

Management: topical antibiotics to prevent concomitant infections

Question 8

Corneal ulcer vs corneal abrasion

Answer 8

A corneal abrasion is a scrape of the top layer, the epithelium, but does not go through Bowman’s layer underneath this. A corneal ulcer is an open sore/erosion (from inflammation or infection) that goes through Bowman’s layer into the deeper layers of the cornea

Question 9

Subconjunctival haemorrhage

Answer 9

The conjunctiva is like a thin ‘skin’ on the front of the eyeball. It covers the white part of the eye (the sclera) but does not cover the central part of the eye (the cornea)

• Blood under conjunctiva
• Commonly due to use of anti-platelets/anti-coagulants
• May have hx of trauma, coughing bouts or uncontrolled hypertension

Clinical features

• Usually uni-lateral, localised & sharply circumscribed=with no visible sclera
• Vision not affected, normally asymptomatic

Management

• Check BP, INR, COAG
• Reassure

Question 10

Endopthalmitis

Answer 10

Severe inflammation of the anterior and posterior chambers of the eye - penetrating trauma or surgery allows bacteria in

Usually bacterial or fungal with infection involving the vitreous and or aqeous humours

Most cases occur after eye surgery or penetrating ocular trauma

Presentation: acute painful eye with decreased vision, eyelid swelling, hypopyon (pus in the anterior chamber), eye may be hazy

Management

Medical emergency, emergency admission

Systemic antibiotics if bacterial

Acute bacterial endopthalmitis is a medical emergency because delay in treatment may result in vision loss

Poor prognosis