The conjunctiva is a relatively loose structure and any bleeding can easily spread and appear quite alarming. Patients are, however, often asymptomatic and may only become aware of having a red eye when looking in the mirror or having it pointed out to them.
The majority of subconjunctival haemorrhages occur spontaneously without an identifiable cause, the patient occasionally complaining of a sudden “popping” feeling in the eye. It is likely that many of these patients may have had mild trauma eg eye rubbing, which has contributed to the bleed.
Subconjunctival haemorrhage: Post operative nasal subconjunctival haemorrhage in the left eye.
Occasionally subconjunctival haemorrhage, especially if recurrent, can be an indication of more serious ocular or systemic disease:
- Subconjunctival haemorrhage secondary to significant direct blunt or sharp injury may be a sign of globe rupture. If there is any doubt urgent referral is necessary for specialist opinion and the patient may require a conjunctival peritomy and exploration of the injured area.
- Recurrent subconjunctival bleeds can be associated with a transient rise in venous pressure eg coughing, vomiting, Valsalva manoeuvre or may be due to uncontrolled hypertension.
- Recurrent subconjunctival bleeds can also be a feature of a systemic bleeding diathesis (ask about easy bruising and epistaxis) or a sign that an individual is over anticoagulated eg high international normalised ratio (INR) with warfarin.
- Acute haemorrhagic conjunctivitis eg adenoviral conjunctivitis, may often have a degree of subconjunctival haemorrhage but the patient would have other associated ocular symptoms +/- lymphadenopathy.
Unless associated with a serious cause no therapy is required and the patient should simply be reassured. The area of haemorrhage usually changes to a yellow-brown colour before resolving in 10 – 12 days.