Understanding Retinal Vascular Occlusions

Imagine one of the veins in your retina—the light-sensitive layer at the back of your eye—gets blocked. When that happens, blood can’t drain properly, so it backs up and causes swelling, bleeding, and fluid leaks. That impacts your vision, especially in the center (the macula).

RVO isn’t rare—especially as we age. About 1 in 200 adults over 40 get it. Most of the time, it’s the smaller branch veins that get blocked (about 84% of cases). The central retinal vein, which is larger, is involved less often (about 16%).

The Different Types

• Branch Retinal Vein Occlusion (BRVO):
  This is the more common one. It usually happens where a small artery crosses over a vein and pinches it off, affecting just part of your retina.
  
  
• Central Retinal Vein Occlusion (CRVO):
  A bit more serious—this is when the main vein gets blocked, near the optic nerve. It affects a wider area and causes more dramatic changes.
  
  
• Hemi-RVO:
  Kind of a halfway point. It blocks one half of the central vein, so it affects about half your retina.
  
  

Who’s More Likely to Get It?

If you have any of these, your risk goes up:

• High blood pressure
  
  
• Diabetes
  
  
• High cholesterol
  
  
• Glaucoma
  
• Being over 50

Retinal artery occlusion is less common but can be more severe because the arteries carry oxygen-rich blood to the retina. RAO typically presents with sudden, painless vision loss, and patients may describe a “black curtain” descending over their field of vision. There are several subtypes, including:

• Central Retinal Artery Occlusion (CRAO): A blockage in the primary artery supplying the retina, which often results in significant vision loss if not treated immediately.
• Branch Retinal Artery Occlusion (BRAO): Involves a blockage in one of the smaller branch arteries, with varying degrees of vision impairment, often with some ability for partial recovery.
• Ophthalmic Artery Occlusion (OAO): A rare occurrence that affects the main artery supplying the eye and can produce severe vision deficits.

Because the retina is highly sensitive to oxygen deprivation, any interruption in its arterial supply is treated as a medical emergency by our retina specialist.

If not managed properly, retinal vascular occlusions can lead to several serious complications. It is important to understand these potential issues so that we can work together to monitor your condition closely.

• Macular Edema: The buildup of fluid in the macula leads to swelling, causing blurred or distorted central vision.
• Neovascularization: This involves the growth of new, abnormal blood vessels, which can bleed or lead to further complications such as increased eye pressure.
• Vitreous Hemorrhage: Bleeding within the gel-like substance of the eye may cloud your vision and complicate the medical picture.
• Neovascular Glaucoma: An increase in eye pressure due to abnormal vascular growth can be painful and further jeopardize vision.
• Retinal Detachment: In severe cases, parts of the retina may separate from the underlying tissue, leading to irreversible vision loss.

Timely intervention, careful monitoring, and adherence to treatment plans can significantly reduce the risk of these complications and help maintain your vision.