• A grossly visible collection of blood in the anterior chamber of the eye
  • Microhyphema refers to red blood cells in the anterior chamber which do not layer out and are not grossly visible.
  • Traumatic hyphema is a common complication of blunt or penetrating trauma to the eye that can result in permanent vision loss.


Annual incidence of 20 cases per 100,000 population (1)


  • Up to 70% occur in children with a peak incidence at 10 to 20 years of age.
  • Males are affected 3 to 5 times more often than females (1).

Etiology and Pathophysiology

  • Blunt trauma is the most common cause, and assault is the most common mechanism.
  • Penetrating trauma
  • Postoperatively following intraocular surgery
  • Neoplasm (retinoblastoma or iris melanoma)
  • Clotting disorders (von Willebrand disease or juvenile xanthogranuloma)
    • Pathophysiology: Posterior displacement of tissue stretches the limbal vessels resulting in a tear and lead to bleeding; red blood cells obstruct outflow of aqueous humor and remain in the anterior chamber.

Risk Factors

  • Trauma
  • Congenital bleeding disorders (sickle cell trait or disease)
  • Anticoagulation
  • Intraocular surgery

Commonly Associated Conditions

Blood dyscrasias such as sickle cell disease

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