Subconjunctival hemorrhage is defined as blood between the conjunctiva and the sclera, and it is involved in the differential diagnosis of a red eye. Subconjunctival hemorrhage results from bleeding of the conjunctival or the episcleral blood vessels into the subconjunctival space. The hemorrhage can be traumatic, spontaneous, or related to systemic illness. Exact figures are unknown because it is a self-limited disorder. No racial preference for subconjunctival hemorrhage is evident.
Most common appearance is a bright red patch with relatively normal surrounding.
Slit lamp examination shows its precise location under the conjunctiva. View of sclera may be obscured by blood. If thick, it may be dark red. Subconjunctival hemorrhage has been reported as a result of emboli from long bone fractures, chest compression, cardiac angiography, open-heart surgery, and other remote operations. Usually, no laboratory studies are indicated.