Neovascular glaucoma (NVG) occurs when blood vessels grow over the iris and anterior chamber of the eye. This prevents fluid from draining, raising pressure in the eye and potentially affecting vision.

The blood vessels can also bleed, which can cause a significant rise in pressure. This may lead to irreversible damage to the optic nerve.

NVG is a serious condition that can cause blindness if a person does not receive appropriate treatment. It links to conditions such as diabetic retinopathy, central retinal vein occlusion, or carotid artery disease (CAD).

This article provides an overview of NVG, including its causes, symptoms, diagnosis, and treatment options.

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NVG is a condition that damages the optic nerve in the eye. Unlike other forms of glaucoma, it develops when atypical blood vessels grow in parts of the eye.

These new blood vessels prevent fluid from draining from the eye and are often leaky. The result of this is increased pressure in the eye, which can result in vision loss if left untreated.

NVG is not life threatening, but it can cause permanent vision loss. Doctors associate it with a poor outlook for a person’s vision.

With early detection and appropriate treatment, the outlook for those with NVG is better.

NVG is a type of secondary glaucoma. This means it develops because a person has another underlying health condition, such as diabetic retinopathy, ocular ischemic syndrome, or ischemic central retinal vein occlusion.

These conditions can block or damage blood vessels in the eye, meaning the retina does not get enough oxygen. As a result, the retina attempts to fix the problem by releasing a chemical known as vascular endothelial growth factor (VEGF).

This chemical causes new blood vessels to grow, bringing more oxygen to the retina. But these new blood vessels can also block eye fluid drainage and leak.

Less common causes of NVG include:

In the early stages, a person may have no symptoms of NVG. Light sensitivity and blurry vision may be among the first signs. As the condition progresses, a person may experience:

  • pain
  • eye redness
  • decreased vision

Sometimes the intensity of the pain and redness is less pronounced, particularly in younger people.

Diagnosing NVG involves a comprehensive eye examination to assess:

  • pressure inside the eye
  • the health of the optic nerve and anterior chamber
  • the drainage angle of the eye
  • a person’s visual field

The eye doctor, or ophthalmologist, may also perform imaging tests to help diagnose and monitor the progression of the disease.

It is essential that doctors identify the underlying cause of NVG, as it is only by addressing the cause that doctors can effectively treat it.

If the cause is not already clear, a doctor may take a thorough medical history to identify any risk factors for NVG and order additional tests to confirm conditions such as diabetes or CAD.

Treatment for NVG involves treating or managing the underlying cause of the condition and reducing eye pressure to help prevent damage to the optic nerve.

How doctors address the underlying cause will depend on what it is, but in general, the goal is to manage reduced blood flow to the retina and reduce the formation of new blood vessels. Doctors can use various approaches for this, such as:

  • a laser treatment known as pan-retinal photocoagulation, which decreases VEGF production
  • injection of anti-VEGF medications directly into the eye to promote the disappearance of new blood vessels

For lowering pressure in the eye, the first-line approach is often eye drops or oral medications.

If medical and laser therapies are unsuccessful, doctors may recommend inserting a tube shunt into the eye to reduce eye pressure.

However, if a person has low vision, ophthalmologists may recommend a less invasive laser procedure to destroy the ciliary body, which is the part of the eye that produces fluid.

The management of NVG often involves a team of specialists, including glaucoma and retina specialists, ophthalmologists, and primary care physicians. These medical specialists work together to ensure the individual receives optimal care and minimizes the risk of total vision loss.

NVG is a type of secondary glaucoma that occurs as a result of conditions that deprive the retina of blood, such as diabetic retinopathy.

In response to the lack of blood, the eye grows new blood vessels, blocking the drainage of fluid from the eye. These new blood vessels can also leak.

This raises pressure in the eye and can damage the optic nerve, causing vision loss. A person may have no symptoms initially.

Doctors diagnose the condition through a comprehensive eye exam. Treatment may involve a combination of medications, laser therapy, or surgery.