Neovascular Glaucoma
Severe glaucoma from abnormal new blood vessels in the eye
Quick Facts
- Type: Severe secondary glaucoma
- Core problem: New vessels block the eye's drainage angle
- Common causes: Diabetic retinopathy, retinal vein occlusion
- Action: Needs urgent eye specialist care
Overview
Glaucoma is a group of eye conditions in which raised pressure inside the eye damages the optic nerve, which carries images to the brain. Neovascular glaucoma (NVG) is a severe form that develops when abnormal new blood vessels grow on the colored part of the eye (the iris) and across the eye's internal drainage system, called the drainage angle.
These new vessels and the scar tissue around them block the normal outflow of fluid from the eye. As fluid builds up, the pressure inside the eye rises sharply, which can damage the optic nerve and cause severe, sometimes permanent, vision loss. NVG almost always develops because another condition has starved the retina of oxygen, most often diabetic retinopathy or a blocked retinal vein. It is a serious, sight-threatening condition that needs prompt specialist care.
Symptoms
Symptoms often appear as eye pressure rises and can be severe:
- Eye pain, sometimes severe
- Redness of the eye
- Blurred or decreasing vision
- Seeing halos around lights
- Sensitivity to light
- Headache, nausea, or vomiting when pressure is very high
Sudden severe eye pain with redness, blurred vision, halos, and nausea is an eye emergency and requires immediate evaluation. Some people with underlying retinal disease may have few symptoms early, which is why those at risk need regular eye exams.
Causes
NVG develops when the retina is deprived of oxygen and releases signals that trigger abnormal vessel growth. Common underlying causes include:
- Diabetic retinopathy: Advanced (proliferative) retinal damage from diabetes is a leading cause.
- Retinal vein occlusion: A blocked vein in the retina starves tissue of oxygen.
- Ocular ischemic syndrome: Reduced blood flow to the eye, often from carotid artery disease.
- Other retinal conditions: Including some retinal artery blockages and inflammatory diseases.
A protein called vascular endothelial growth factor (VEGF), released by the oxygen-starved retina, drives the abnormal vessel growth and is a target of treatment.
Risk Factors
- Long-standing or poorly controlled diabetes with retinopathy
- Retinal vein or artery occlusion
- Carotid artery disease or reduced blood flow to the eye
- Other causes of retinal oxygen shortage
- Delayed treatment of underlying retinal disease
Diagnosis
An eye specialist diagnoses NVG through examination and imaging:
- Eye pressure measurement: Checks for raised intraocular pressure.
- Slit-lamp examination: Reveals new blood vessels on the iris (a sign called rubeosis).
- Gonioscopy: A special lens to view the drainage angle and detect new vessels or blockage there.
- Retinal examination and imaging: A dilated exam, plus tests such as fluorescein angiography or OCT, to find the underlying retinal disease.
Treatment
Treatment has two goals: lowering eye pressure and treating the underlying retinal disease driving the new vessels. Care is led by an eye specialist.
- Lowering eye pressure: Eye drops and other medicines, and procedures or surgery (such as drainage devices) when needed.
- Anti-VEGF injections: Medicine injected into the eye can shrink the abnormal new vessels.
- Laser treatment: Panretinal laser photocoagulation treats the oxygen-starved retina and reduces the signal that drives new vessel growth.
- Treating the cause: Managing diabetes, retinal vein occlusion, or reduced blood flow to the eye.
- Comfort and protection: Care to control pain and preserve as much vision as possible.
Early treatment offers the best chance of saving vision, while advanced cases may aim mainly to control pressure and relieve discomfort.
Prevention
- Keep diabetes well controlled and attend all dilated eye exams
- Get prompt treatment for diabetic retinopathy or a retinal vein occlusion
- Manage blood pressure, cholesterol, and carotid artery disease
- Do not smoke
- Report any eye pain, redness, or vision change without delay
- Follow your eye specialist's schedule for monitoring high-risk eyes
When to See a Doctor
People with diabetic retinopathy or a retinal vein occlusion should have close eye follow-up. Seek urgent eye care if you have:
- Sudden or severe eye pain
- A red eye with blurred or decreasing vision
- Halos around lights
- Headache, nausea, or vomiting with eye pain
- Any sudden change in vision
Rapidly rising eye pressure can permanently damage vision, so do not delay evaluation.
Frequently Asked Questions
What is neovascular glaucoma?
It is a severe form of glaucoma in which abnormal new blood vessels grow on the iris and across the eye's drainage angle, blocking fluid outflow. This raises pressure inside the eye and can damage the optic nerve and threaten vision.
What causes it?
It usually develops when the retina is starved of oxygen and releases signals that trigger new vessel growth. The most common causes are advanced diabetic retinopathy and retinal vein occlusion, along with reduced blood flow to the eye.
What are the warning signs?
Eye pain, redness, blurred or decreasing vision, halos around lights, and sometimes headache, nausea, or vomiting. Sudden severe eye pain with these symptoms is an emergency and needs immediate care.
How is neovascular glaucoma treated?
Treatment lowers eye pressure with medicines and sometimes surgery, while also treating the underlying retinal disease with anti-VEGF injections and laser therapy. Controlling the cause, such as diabetes, is essential.
Can vision be saved?
Vision can often be preserved if the condition is found and treated early, before lasting optic nerve damage occurs. In advanced cases, treatment may focus on controlling pressure and relieving pain. Regular eye exams in high-risk people are key.
References
- American Academy of Ophthalmology. Neovascular glaucoma.
- National Eye Institute (NEI). Glaucoma and diabetic eye disease.
- MedlinePlus, U.S. National Library of Medicine. Glaucoma.
- Centers for Disease Control and Prevention (CDC). Diabetes and vision loss.