Retrobulbar bleeding

Retrobulbar bleeding, also known as retrobulbar hemorrhage, is when bleeding occurs behind the eye.^[1] Symptoms may include pain, bruising around the eye, the eye bulging outwards, vomiting, and vision loss.^[1] Bleeding in the enclosed retrobulbar space causes pressure to build up behind the eye. This increased eye pressure leads to damage of the optic nerve and disruption of blood flow in the retinal artery leading to blindness.^[2]

Retrobulbar bleeding can occur as a result of trauma to the eye, surgery to the eye, blood thinners, or an arteriovenous malformation.^[1]

In those with suspected retrobulbar bleeding, lateral canthotomy with cantholysis is indicated. This involves cutting tissue between the globe (eyeball) and the lateral corner of the lower eyelid, to allow pressure (retrobulbar pressure) to escape from the enclosed retrobulbar space behind the eye.^[1] This is recommended to be carried out within two hours.^[1] If a lateral canthotomy does not relief retrobulbar pressure, orbital bone decompression can be done. This is when parts of the bones lining the orbit are removed to allow pressure, and blood to escape.^[3] The condition is rare.^[1]

A 2018 systematic review found that 74% of retrobulbar bleeds occur after trauma and 26% occur after eye surgery.^[2] The review found that symptoms in retrobulbar bleeds typically start after 24 hours of an inciting event.^[2] Older age, eye trauma, delays in treatment, and having more symptoms were associated with worse outcomes with regards to vision loss.^[2] Surgical decompression (manually evacuating blood from behind the eye) was associated with better preservation of vision as compared to non-surgical treatment.^[2] Regarding treatment for retrobulbar bleeds; the 2018 review found that 51% of people had a complete recovery of vision, 27% of people had partial recovery of vision, and 22% were blind. Steroids had no benefit in treatment.^[2]

Retrobulbar bleeding is estimated to complicate 0.45-0.6% of orbital fractures.^[2]