Retinal Vein Occlusion

The retinal artery and vein carry blood in and out the eye. Retinal vein occlusion occurs when the retinal vein or a branch of the vein closes. The 2 main types of retinal vein occlusion include CRVO (central retinal vein occlusion) and BRVO (branch retinal vein occlusion).

Closure of a blood vessel in the eye can act as a signpost that you may be at increased risk of cardiovascular and cerebrovascular disease.

Enquire about Retinal Vein Occlusion at one of our London Clinics

Vitreous and Retinal haemorrhage

Vitreous Haemorrhage
This occurs when blood from the closed veins leaks into the vitreous humour inside the eye, usually at the back of the eye. The vitreous humour is a clear jelly-like substance that supports the shape of the eye whilst letting light through. As a result of blood leaking into this section of the eye vision can be lost in varying degrees from mild with floaters, haziness to total vision loss.

Retinal Haemorrhage

This is similar to a vitreous haemorrhage, but the leaking blood fills the retina of the eye. The symptoms for this are:

  • Seeing floaters in the vision
  • Seeing cobwebs in the vision
  • Seeing haze or shadows
  • Distorted vision
  • Rapid flashes of light in peripheral vision
  • Red tint to vision
  • Blurred vison
  • Sudden blindness

The vision created by the haemorrhages from retinal occlusion is often referred to as occlusion vision. If you develop any of these symptoms it is important to see a consultant.

The Eye Can Try To Repair Itself – Growth of new blood vessels

Once the blood vessel closes due to the retinal occlusion, the retina becomes damaged and releases molecules ( Vascular endothelial growth factor or Veg F) to help stimulate the development of new blood vessels. Unfortunately these blood vessels are unstable and weak. They can easily tear and leak causing further hemorrhaging inside the eye causing scarring and retinal detachments in extreme cases as well as raised eye pressure ( glaucoma).

Macular oedema

The macula is an area within the retina responsible for central vision and fine vision.
Retinal vein closure can cause macular damage and fluid to accumulate in the macula potentially resulting in significant sight loss.

Am I at risk of retinal occlusion?

There are a lot of causes of retinal vein occlusion and these include

  • High blood pressure
  • Diabetes
  • Glaucoma
  • Hardening of the arteries
  • Certain inflammatory conditions

To lower your risk for CRVO, you should do the following:

  • Eat a low-fat diet
  • Get regular exercise
  • Maintain an ideal weight
  • Don’t smoke


At Olelo, we can offer sight saving treatment with state of the art intravitreal injections and laser therapy.

Intravitreal Injections

Ocular injections of vision saving medicines directly into the back of the eye not only preserves your vision, but in half the patients, can reverse vision loss significantly.

These are office based procedures and painless, performed under local anaesthetic.
These are taken on a regular basis throughout the first year and then depending upon treatment results, injections are also given in the second year of treatment.

Usually a family of medicines known as Anti Veg F medicines such as Eylea or Lucentis are injected.

At Olelo, treatments with Eylea, Lucentis and Avastin are all available to patients.

In our Olelo clinics, we encourage early detection to our patients and their families and we are committed to providing state-of-the-art total care for retinal occlusion patients with diagnosis, education, prevention and treatment.