Subconjunctival haemorrhage. This is due to a bleed into the subconjunctival space. There may or may not be a history of a contributory factor, such as straining with coughing or constipation. It may be associated with hypertension. On examination, there is an area of localised, well-demarcated haemorrhage in one eye, in the absence of pain, no reduction of visual acuity, normal pupil reactions, and no corneal staining.