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Two-week rule not working

Red Eye


Case history

I agree. He has obvious red flags ­ only one eye affected, blurred vision and a job that makes him prone to foreign bodies. Most patients appreciate a clear explanation and will be happy to come to the surgery to be examined, no matter how busy their work.


·Watery ­ viral conjunctivitis

·Purulent ­ bacterial conjunctivitis

·Excessive lacrimation ­ allergic conjunctivitis, foreign body and corneal abrasions

·Itchy or gritty ­ allergic conjunctivitis

·Burning ­ bacterial or viral conjunctivitis

·Pain ­ anterior uveitis (moderate), glaucoma (severe pain often with nausea, vomiting and headache)

·Vision ­ a unilateral painful red eye accompanied by even mild visual loss must be treated with suspicion; corneal abrasions, keratitis, glaucoma and uveitis can all cause problems.

·Mild ­ infective conjunctivitis

·Severe ­ keratitis (eg arc eye, corneal ulcer)

Arc eye typically develops some hours

after exposure. Discomfort is usually described as 'sand in the eye' and usually lasts 12-24 hours. Problems occur in welders and users of sunbeds who use inadequate eye protection. Symptoms are bilateral.

Anterior uveitis tends to affect the young and middle-aged. In almost half of people who present it is associated with systemic conditions such as Reiter's syndrome, ankylosing spondylitis, Still's disease, TB, sarcoid, Crohn's, syphilis and carcinomatosis. Family history may also be relevant ­ look for atopy and eye conditions such as glaucoma.

Soft contact lenses are more likely to produce serious corneal infections than hard or gas permeable lenses. Typical infecting organisms include pseudomonas and acanthamoeba.

Some drugs ­ anticholinergics or sympthomimetics ­ can precipitate acute glaucoma.

Look for the following:

·Purulent discharge. If it is obvious and bilateral examination is usually over unless other red flags are present. Give antibiotics and send patient home.

If not present or not bilateral ­ examine the eye more closely.

·Bilateral eyelid oedema ­ allergic conditions such as hay fever or pet allergies.

·Herpes zoster lesions on the eyelid usually means the eye is also involved.

·Pattern of redness ­ a localised area (often triangular) usually indicates episcleritis. Redness is circumcorneal in acute glaucoma and anterior uveitis. In scleritis the whole eyeball looks purplish-red with accompanying visual loss and pain.

·Talbot's signs ­ positive in anterior uveitis. Pain worsens as eyes converge and pupils constrict.

·A fixed, dilated, occasionally ovoid pupil means glaucoma. Miosis ( a small pupil) may indicate anterior uveitis.

·Look under the eyelids to exclude foreign bodies. Removal will give instant relief.

·The cornea and iris should then be examined. A hazy cornea indicates acute glaucoma. Instilling a drop of fluorescein will reveal corneal lesions when inspected under a blue light. Lesions appear green, abrasions as streaks, herpetic ulcers as dendritic and UV exposure as multiple punctuate lesions. Fungal lesions (candida, aspergillus) may show up as grey indolent ulcers.

·If you suspect glaucoma, a shallow anterior chamber may be noticed in the other eye. Shine a torch from the side ­ half the iris lies in shadow. Raised intra-ocular pressure may also make the eyeball feel hard to digital pressure.

·Use an ophthalmoscope to detect corneal foreign bodies. A hypopyon (a fluid level of exudates) may also be seen in the anterior chamber due to leakage of proteins into the aqueous during an attack of anterior uveitis.

·If the patient complains of visual impairment measure acuity with a Snellen chart.

·In acute glaucoma intraocular pressures (IOPs) can rise from normal (15-21mmHg) to 60-80mmHg. These must be monitored closely to ensure treatment is working. Family members should also have their IOPs checked.

·Any patient with a first presentation of anterior uveitis should be thoroughly investigated to exclude systemic illness.

·CT scan may be required if you have a good history of a high-velocity foreign body entering the eye.

Remember to refer corneal metallic foreign bodies as they can leave a 'rust ring.' All fungal infections and herpes zoster should be referred. The latter is usually treated with long-term steroids and topical aciclovir.

Acute closed-angle glaucoma is an ophthalmic emergency and inpatient treatment involves 2-4% pilocarpine to induce miosis (which opens up the closed angle) and acetazolamide. Once stable the patient undergoes a peripheral iridectomy (at the 12 o'clock position) in both eyes to allow free aqueous flow.

Episcleritis is usually self-limiting. Treatment, if required, is usually with oral NSAIDs and steroid eye drops. Scleritis is a medical emergency and immediate referral is warranted for IV steroids.

Almost never ­ 750 eyes per year suffer significant visual handicap from inappropriate use of steroids. The one exception is patients with a past history of anterior uveitis who present with a unilateral red eye and ask you for their usual steroids. Prolonged anterior uveitis can lead to a disruption of aqueous flow and eventually glaucoma. Therapy involves steroid eye drops and cyclopegic medication. Patients need regular slit-lamp assessment and are therefore best followed by an ophthalmologist.

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