Vitreous hemorrhages have an incidence of 7 cases per 100,000, making them one of the most common causes of acutely decreased vision. The mechanisms related to a vitreous hemorrhage fall into three main categories: 1) abnormal vessels that are prone to bleeding (DIABETES), 2) normal vessels that rupture under stress (POSTERIOR VITREOUS DETACHMENT), or 3) extension of blood from an adjacent source.

During a posterior vitreous detachment, vitreous traction on the retinal vasculature may compromise a blood vessel, especially at the firm attachments. This may happen with or without a retinal tear or detachment. However, a vitreous hemorrhage in the setting of an acute symptomatic posterior vitreous detachment should alert the eye specialist that the risk of a concurrent retinal break is very high (70-95%).