Membership information 0800 225 677
Medicolegal advice 0800 982 766

The red eye?

01 November 2005

Mrs O, a 54-year-old secretary with a history of migraine, developed a severe frontal headache, noticing flashing lights and cloudiness in her field of vision. These symptoms came on over about 24 hours. She was visited at home by Dr R, who was working for an out-of-hours GP co-operative. Dr R noted the symptoms of headache, ‘misty’ vision and red eye. Dr R diagnosed conjunctivitis, prescribing topical fusidic acid ointment.

By the next day Mrs O was much worse; she had an excruciating headache, photophobia and vomiting. Her vision was worsening and she requested a further home visit. Dr M attended and noted that there was inflammation of the right conjunctiva.

Both corneas appeared normal and the pupils were equally reactive. She diagnosed migraine and gave Mrs O an intramuscular injection of diclofenac. Dr M advised Mrs O to attend the emergency department of her local hospital if things didn’t settle within 48 hours.


  • severe pain
  • photophobia
  • reduced vision
  • coloured halos around point of light in the patient's vision
  • ciliary flush
  • high intraocular pressure
  • corneal epithelial disruption
  • corneal opacity
  • proptosis
  • a smaller pupil in the problem eye
  • shallow anterior chamber depth

Mrs O went to hospital two days later where acute angle-closure glaucoma was diagnosed. After pharmaceutical treatment she underwent a right-sided trabeculectomy a few days later. Mrs O’s vision was seriously and permanently impaired in both eyes. She was registered partially sighted and her ophthalmologist anticipated that she would be registered blind within five years.

Mrs O made a claim naming Drs R and M, alleging a failure to suspect or diagnose acute glaucoma as the cause of her symptoms.

Expert opinion

A GP expert discussed the case with Dr M, who reported that Mrs O had not mentioned any problems with her vision; this, combined with the absence of corneal or pupillary signs, had led her to reject a diagnosis of acute glaucoma.

Despite this, the expert felt that Dr M’s actions would be difficult to defend; even if this symptom was not volunteered, it should have formed part of Dr M’s routine assessment, been directly asked about and documented in the notes.

Mrs O had given a clear history of visual cloudiness to Dr R on the preceding day. The expert felt that the combination of severe pain, visual impairment and red eye should have prompted Dr R to seek an emergency ophthalmological opinion after Mrs O’s first presentation.

An ophthalmology expert concluded that the 48-hour delay in Mrs O’s ophthalmological assessment had led to severe and irreversible damage to both eyes with no prospect of recovery.

The claim was settled out-of-court, and liability shared equally between the two GPs. 

Learning points

Assessing the ‘red'

Whilst this symptom/sign is extremely common it indicates serious ocular pathology until proven otherwise. Concurrent symptoms, which should amplify the warning a red eye gives, are severe pain, headache, visual disturbance, the presence of visual ‘halos’ and nausea.

A systematic approach with adequate documentation gives the best protection to patient and doctor alike. Make sure that you have considered possible alternative diagnoses to conjunctivitis before reaching for the chloramphenicol drops.

A recommended text for those wishing to improve their ophthalmological knowledge is: Khaw PT, Shah P, Elkington AR, ABC of Eyes, 4th Edition, BMJ Publishing Group (2004). It has a handy problem-based chapter on assessment of the red eye in primary care, and would be a useful reference text to keep at hand in any GP surgery or emergency department. For an online tutorial on this subject see

Sticking with a diagnosis

If all the symptoms do not fit together with a particular diagnosis, it is time to go back to the drawing board. This is particularly true if, as in the case for ‘red eye’ the alternative diagnoses can include time-critical conditions with potentially serious outcomes.