Retinal Vein Occlusion (RVO)

Retinal vein occlusion occurs when one of the veins draining the retina becomes blocked. RVO is the second most common retinal vascular disease. RVO may occur in the central retinal vein (CRVO) or a branch retinal vein (BRVO), although the occurrence of BRVO is more common. Both conditions are thought to be the result of a combination of factors involving degenerative changes to the vessel walls and hypercoagulability.

Risk Factors for RVO

  • Increasing age
  • Hypertension
  • Hyperlipidemia
  • Retinal arteriolar abnormalities
  • Increased intraocular pressure

In addition, CRVO and BRVO also have unique risk factors.


  • Diabetes Mellitus
  • Smoking
  • Use of oral contraceptive pill


  • Increased BMI

Symptoms of RVO

RVO is a painless disease that leads is characterized by visual deficits. People may experience floater or flashes of light.

The onset of CRVO is often acute causing a sudden loss of vision in one eye if there is decreased perfusion from the blockage. In those with non-ischemic CRVO, the visual changes are milder and usually improve as the day progresses.

BRVO is often asymptomatic. In those with visual changes, the symptoms are related to the location of the obstruction. BRVO of the nasal retinal quadrants presents with blurred vision, while occlusions associated with macular edema often present with central field defect. 

What is the treatment of RVO? 

Treatment options for RVO target the sequelae of RVO, including macular edema and neovascularization. There are several treatment modalities available:

  • Laser photocoagulation
  • Surgical decompression
  • Intravitreal corticosteroids
  • Intravitreal anti-VEGF agents

Source: REHAK, M., & WIEDEMANN, P. (2010). Retinal vein thrombosis: pathogenesis and management. Journal of Thrombosis and Haemostasis, 8(9), 1886–1894.