Neovascularization of The Eye

What is neovascularization of the eye?

Neovascularization of the eye refers to new blood vessels forming where and when they shouldn’t form. There may also be too many of them, even if they’re in the right place. New fibrous tissues often form afterward between the new vessels, which can decrease vision.

Neovascularization in your eye can cause inflammation and scarring and may result in loss of vision.

Neovascularization usually happens as a result of injury or disease. In your eye, it can affect your:

• Choroid: The choroid is a layer of tissue in your eye located between your retina and sclera that is filled with blood vessels.
• Retina: The retina is the part of your eye that converts light into electrical signals that travel to your brain.
• Macula: The macula is the part of your eye that processes what you see right in front of you. It’s located near the center of your retina.
• Iris: The iris is the colored part of your eye that contains your pupil (the dark circle in your eye).
• Cornea: The cornea is the clear “window” at the front of your eye.
• Conjunctiva: The conjunctiva is a film that protects your eye.

What is choroidal neovascularization?

Choroidal neovascularization (CNV) refers to new blood vessels in your choroid.

This type of condition most often happens in people who have age-related macular degeneration (AMD). Experts believe high levels of vascular endothelial growth factor (VEGF) made by the retina in someone with AMD cause CNV.

The new blood vessels that grow aren’t normal. They let fluid and sometimes even blood leak into the retina. Fluid and blood may cause a blister in your retina.

The things that cause CNV can cause macular neovascularization (MNV). However, there are MNV cases with an unknown cause. These are called idiopathic.

What is corneal neovascularization?

Corneal neovascularization refers to new blood vessels growing in your cornea, an area of your eye that normally doesn’t have blood vessels. Your cornea is normally clear, but blood vessels cause changes that may interfere with how transparent your cornea is.

Corneal neovascularization is associated with many kinds of eye conditions.

What is retinal neovascularization?

Retinal neovascularization refers to new abnormal blood vessel growth in your retina, the part of your eye that contains light-sensing cells. Diseases and injuries can cause this.

What is neovascularization of the iris?

Iris neovascularization is the term for new and abnormal blood vessel growth on the iris of your eye. Another name for this condition is rubeosis iridis. It’s related to a type of glaucoma called neovascular glaucoma. Glaucoma, which harms your optic nerve, is also a threat to vision.

What are the signs and symptoms of neovascularization of the eye?

Symptoms and signs of ocular neovascularization may vary depending on what area is affected.

Signs and symptoms of choroidal neovascularization and macular neovascularization

• You see distorted or wavy images.
• You have an empty or dark spot in your central vision.

Signs and symptoms of corneal vascularization

You may not have symptoms if you have corneal vascularization, but if you do, you might have:

• Eye pain.
• Redness.
• Watery eyes.
• Sensitivity to light (photophobia).
• An inability to wear contact lenses for longer than a few hours.

What causes neovascularization of the eye?

There are many things that can cause ocular neovascularization.

Causes of choroidal neovascularization and macular neovascularization

• Macular degeneration.
• Extreme nearsightedness.
• Ocular histoplasmosis, a type of fungal infection.
• Eye injury.
• Angioid streaks, which are cracks in one of the layers of your retina.
• Uveitis, a group of eye diseases that can cause inflammation, red eyes and eye pain.

Causes of corneal neovascularization

• Congenital diseases (diseases you’re born with).
• Eye trauma, like chemical burns.
• Infectious keratitis.
• Allergies.
• Immune system and inflammatory disorders.
• Hypoxia (lack of oxygen in tissues) caused by contact lenses.
• Rejection of a corneal graft.

Causes of retinal neovascularization

• Retinitis.
• Retinopathy, including diabetes-related retinopathy, sickle cell retinopathy and retinopathy of prematurity.
• Poor blood flow in your carotid arteries.
• Retinal vein occlusion (a blockage in your retinal vein).

Causes of neovascularization of the iris

• Diabetes-related retinopathy.
• Central retinal vein occlusion.
• Ocular ischemic syndrome.
• Retinal detachment, where the retina pulls away from its supportive tissue.
• Uveitis.

What tests can diagnose neovascularization of the eye?

A provider can detect neovascularization of the eye using a variety of techniques. They may include:

• A dilated slit lamp eye exam.
• Optical coherence tomography.
• Fluorescein or indocyanine green angiography.

How is neovascularization of the eye treated?

Treatment of ocular neovascularization depends on the cause of the neovascularization of the eye. Typically, these treatments include medications and/or ablation (destruction) of the blood vessels. These medications include:

• Bevacizumab (Avastin®), used off-label.
• Brolucizumab (Beovu®).
• Aflibercept (Eylea®).
• Ranibizumab (Lucentis®).
• Gene therapy.
• MMP inhibitors, such as doxycycline (for corneal neovascularization).

A provider may destroy the abnormal tissue using:

• Laser ablation therapy: The method uses lasers to treat the vessels.
• Photodynamic therapy: This method combines light and medications that react to light to destroy tissue.
• Cauterization: This method uses heat to treat abnormal vessels.

These methods may have complications. For instance, both steroids and anti-VEGF medicines can cause side effects throughout your body. Ablation may sometimes affect healthy tissue. Talk to your healthcare provider about the risk and benefits of each treatment.

How can I prevent neovascularization of the eye?

There are things that you can do to protect your eyes, including:

• Make sure your hands are clean when you have to touch your eyes.
• Follow instructions on using and cleaning contact lenses. Don’t wear them longer than you’re supposed to.
• Ask your provider about foods or supplements that may help to keep your eyes healthy. There are supplements called AREDS 2 that may help people who have earlier stages of AMD to slow or stop the progression of the disease.
• Follow healthy lifestyle habits, like eating well and getting regular exercise.

What can I expect if I have neovascularization of the eye?

If neovascularization isn’t treated, you may lose your vision. This can affect your quality of life.

Successful treatment may depend on where the neovascularization is taking place, your age and whether or not you have other health conditions.

When should I see a healthcare provider?

Always see a healthcare provider immediately if you have a sudden loss of vision or eye pain. Contact an eye care provider if you notice vision changes or other symptoms that concern you.

You should see your eye care provider as often as they recommend. If you have certain eye conditions, you may need more frequent visits.

What questions should I ask my healthcare provider?

You may want to ask your provider any of the following questions:

• What type of neovascularization of the eye do I have?
• Am I eligible to participate in clinical trials?
• Can you suggest aids or resources to help me deal with low vision?

What is the difference between neovascularization and angiogenesis?

Angiogenesis refers to blood vessels forming from previously existing blood vessels. Vasculogenesis refers to vessels starting from cells (sort of like starting from scratch). Neovascularization combines both ways of developing new blood vessels.

A note from Cleveland Clinic

It’s normal to be anxious when you face a threat to your eyesight. In addition to following healthy lifestyle habits, it’s good to get regular eye exams. It’s also important to reach out to a healthcare provider whenever you have any change in your vision. In nearly every case, treatment that starts early is better for you than treatment that’s delayed.