דימום תת-לחמית

What is a subconjunctival haemorrhage?

Subconjunctival haemorrhage results from bleeding of the conjunctival or episcleral blood vessels into the subconjunctival space. Causes may be traumatic or non-traumatic. Non-traumatic causes may be idiopathic or associated with other medical conditions.

Subconjunctival haemorrhage epidemiology¹

• It is a common presentation.

• The incidence of non-traumatic versus traumatic subconjunctival haemorrhage depends on the characteristics of the population.

• One Taiwanese study reported a mean annual incidence of non-traumatic subconjunctival haemorrhage to be about 0.6%.²

• It can occur at all ages but is more common with increasing age, probably as a result of increasing frequency of risk factors.³

• There is little robust evidence about gender differences. One study reported that non-traumatic subconjunctival haemorrhage is more common in women than men.² Another study reported that traumatic subconjunctival haemorrhage is more common in young men.⁴

• It is common in the newborn.

Subconjunctival haemorrhage causes (aetiology)¹

The cause of a subconjunctival haemorrhage is usually idiopathic.

גורמים נוספים כוללים:

• Valsalva manoeuvre (eg, coughing, sneezing, vomiting or straining; weight lifting; it has also been reported as a complication of bronchoscopy and endoscopy.⁵ )

• Trauma - surgical or accidental (isolated or associated with retrobulbar haemorrhage or ruptured globe). This can include minor trauma, such as rubbing the eye, which the patient may not recall.

• Contact lenses.⁶

• יתר לחץ דם.

• Bleeding disorders.

• סוכרת.

• היפרליפידמיה.

• Coronary heart disease.

• Drugs - eg, warfarin, aspirin and other non-steroidal anti-inflammatory drugs (NSAIDs), steroids.

• Normal sequelae of ocular surgery even if there is no conjunctival incision.

• Febrile systemic infections.

Diseases which can present with subconjunctival haemorrhage include:⁷

• Stevens-Johnson syndrome.

• Haemochromatosis.

• Pyogenic granuloma.

• Telangiectasias.

• Haemangiomas.

Subconjunctival haemorrhage symptoms

• Red eye, usually unilateral.

• It is usually asymptomatic, but there may be mild irritation of the eye.

• The patient may not be aware of its presence but it has been reported to them by family or friends, who can find its appearance quite alarming.

סימנים

• The most common appearance is a flat, bright red patch anywhere in the conjunctiva with sharply defined edges and relatively normal conjunctiva surrounding it.

• Overall, subconjunctival haemorrhages are most commonly found in the inferior conjunctiva, but traumatic subconjunctival haemorrhages are more common in the temporal area and tend to be more localised.⁸

• The haemorrhage may spread and become green or yellow, like a bruise. Usually it disappears within two weeks.

• Examination of the eye, including pupil responses and visual acuity, is otherwise normal.

It is worth noting that a haemorrhage without a posterior margin (ie extends posteriorly so that the whole extent of the haemorrhage cannot be seen) may be associated with an intracranial bleed or an orbital roof fracture (associated with a black eye) - the history should guide you as to whether to consider this or not.

Subconjunctival haemorrhage: "Red eye"

© Standardissue at en.wikipedia,CC BY-SA 3.0, via Wikimedia Commons

הצגה בגודל גדול יותר

אבחנה מבדלת

גורמים אחרים ל acute red eye, including:

• Conjunctivitis.

• Episcleritis.

• Uveitis.
  

• Acute angle-closure glaucoma.

• קרטיטיס.

If it is a persistent haemorrhage (as opposed to the conjunctival injection seen in a red eye), consider rarer causes such as:

• Kaposi's sarcoma.

• Other conjunctival neoplasms.

חקירות

• Check blood pressure.

• No laboratory studies are indicated if it is an isolated problem.

• If there is history of trauma, the patient may need referral to rule out more extensive eye injury.

• In recurrent cases, investigation for an underlying bleeding disorder may be indicated.⁹

Subconjunctival haemorrhage treatment

• Medical care is not required, unless there is an underlying disorder.

• Artificial tears can be used four times per day for mild eye irritation.

• Discourage elective use of aspirin products or NSAIDs.

• Simultaneous bilateral haemorrhages, and persistent or unexplained recurrence, warrant a referral to the ophthalmologist.

• Consider non-accidental injury in infants with bilateral isolated subconjunctival haemorrhages, especially if associated with facial petechiae.

תחזית

• Subconjunctival haemorrhage is a benign, self-limiting condition when not associated with systemic illness.

• The prognosis is excellent.

• There may be a small increased risk of stroke in the three years following a subconjunctival haemorrhage.¹⁰