Risk factors:
(1) uncontrolled hypertension
(2) vascular disease (vasculitis, vascular malformation)
(3) coagulation disorder
(3a) coagulopathy with or without thrombocytopenia with or without platelet function defect
(3b) anticoagulants
(3c) antiplatelet drugs (including aspirin, NSAIDS and glycoprotein IIb/IIIa inhibitor, herbal drugs)
(4) Valsalva maneuver (may be associated with severe coughing or vomiting)
(5) dependent head position
(6) vigorous activity
(7) trauma
(7a) orbital fracture
(7b) blunt or penetrating trauma
(7c) associated with local anesthesia with injections in and around the eye
(7d) during or after surgery (blepharoplasty, facial fracture repair, endoscopic sinus surgery, aneurysm repair, other eye surgery, surgery on the orbit, surgery involving the dural sinus, etc)
(7e) during or after dental surgery (third molar extraction)
(7f) associated with endotracheal intubation
Most cases occur following a traumatic event, but occasionally the hemorrhage may occur without preceding event if other factors are present and severe enough.
