Subconjunctival haemorrhage

Subconjunctival haemorrhage

1. SUBCONJUNCTIVAL HAEMORRHAGE Brian Mwaura Njoroge.

2. Definition. A common benign condition of the eye that has characteristic features, such as the painless acute appearance of a sharply circumscribed redness of bleeding underneath the conjunctiva in the absence of discharge, and inflammation in contagious areas. Histologically, SCH can be defined as hemorrhage between the conjunctiva and episclera, and the blood elements are found in the substantia propria of the conjunctiva when a sub conjunctival vessel breaks.

3. Etiology. Typically seen in older individuals, over 50 years due to hypertension, diabetes mellitus, hyperlipidemia and anticoagulant use. More prevalent in young males most likely related to performing heavy work and tendency to do more aggressive activities . Differentiated into two categories: traumatic vs spontaneous . Traumatic SCH is more likely to remain localized around the site of impact compared to diffuse SCH-associated systemic vascular disorders.

4. Traumatic causes include: Foreign body penetration. Eye rubbing. Orbital fracture- typically occur in 12-24hours after fracture. Base of skull fractures such as basilar fracture present with SCH after 24 hrs. or more after injury. Contact lenses use. Ocular surgery- cataract surgery refractive and local anaesthesia like sub Tenon injections can potentiate SCH especially in patients on anticoagulant therapy. Conjunctival tumors. Ocular amyloidosis. Ocular adnexal tumors- Recurrent SCHs have been reported as the initial sign of anaplastic carcinoma of the lacrimal gland.

5. Spontaneous causes include: Traumatic asphyxia syndrome which is caused by prolonged compression of a child's upper abdomen and chest can cause sudden severe venous congestion. Arteriosclerosis. Systemic hypertension. Diabetes. Hematological dyscrasias such as thrombocytopenia and TTP. Anticoagulant and antiplatelet therapy aspirin and warfarin use. Emboli such as fat emboli from long bone fracture may lead to splinter hemorrhage in upper fornix

6. Pathophysiology. Sub conjunctival hemorrhage results from bleeding of the conjunctival or episclera blood vessels and subsequently leaks into the sub conjunctival space. Blood vessels can wear and tear over time. The elastic and connective tissues become fragile with age and underlying comorbidities which can result in the ease of spread of the hemorrhage in the elderly . Traumatic SCH is more localized to the site of impact compared to spontaneous. There is a predilection for SCH to develop on the temporal aspect of the eye since the bulbar conjunctiva of the temporal aspect is larger than the nasal aspect. Other reasons include increased incidence of conjunctivochalasis, protection of the nose on the nasal aspect, and more difficulty detecting projectiles on the temporal aspect . The inferior aspect was noted to have increased incidence of SCH compared to superior likely to blood gravitating downwards after insult.

7. Clinical presentation. Typically present with red eye and patient may not be aware. No visual disturbances. No discharge. Usually asymptomatic but a momentary sharp pain or a snapping or popping sensation is sometimes felt precipitated by cough, sneeze or vomiting.

8. Investigations. Slit lump to check for local causes. Others will be guided by history. Full blood count Clotting studies.- INR, PT APPT Biopsy. Hba1c.

9. Management. Manage the underlying cause. Typically resolve within 1- 2 weeks. Thus reassure patient.  Ice packs and artificial tears can be utilized to minimize tissue swelling and provide some relief of discomfort respectively . Dilute brimonidine and oxymetazoline has been indicated to improve patient comfort and decrease the incidence of SCH after intravitreal injections . Usage for tissue plasminogen activator alongside its use in vitreous, anterior chamber, and glaucoma filter bleb to induce the clearance of fibrin clots . Failure to resolve hemorrhage in persistent or recurrent cases suggests a serious underlying cause.

10. References. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3702240 / https://www.ncbi.nlm.nih.gov/books/NBK551666 / John F. Salmon (2020).   Kanski’s clinical ophthalmology   (9th ed.). Elsevier Limited.