NEOVASCULARIZATION AND GLAUCOMA

Dr. Carolina Valdivia answers a question about neovascularization (formation of new blood vessels) and how it can impact the progression of glaucoma.

Dear Dr. Valdivia,

I am a glaucoma patient and I take the medications Azopt and Lumigan to control my intraocular pressure. My glaucoma was caused by central retinal vein occlusion, which since has cleared up by about 95%. Will my glaucoma progress the same as if it were caused primarily by high intraocular pressure?



Thank you for your question and for your confidence in glaucoma-eye-info.com.

There are several types of glaucoma. Glaucoma that is caused by other diseases, such as central retinal vein occlusion, are called secondary glaucomas. One example of a secondary glaucoma is neovascular glaucoma that is caused by blockage of the central retinal vein. The most common cause of this blockage is diabetic retinopathy.

The most important message for you to take from the neovascular glaucoma article is that the origin and progression of this type of glaucoma is very different from that described for primary open-angle glaucoma or primary angle-closure glaucoma. Neovascular glaucoma is caused by an abnormal formation of new blood vessels (called neovascularization) in and around the iris of the eye and over the drainage channels in the eye's anterior chamber angle (iridocorneal angle), causing elevations in intraocular pressure. This does not occur on its own and most often is associated with complications from diabetes or elevated cholesterol, causing central retinal vein occlusion or or blockage of the central retinal artery.

In your case, you have two positive factors working for you.

• Your central retinal vein occlusion has resolved significantly (95%).
• Your intraocular pressure appears to be controlled with Azopt and Lumigan.

Although neovascular glaucoma is very difficult to treat, even more so than treatment of primary glaucomas, each case has its own unique characteristics and the treatment plan must take these factors into account. Your ophthalmologist must also consider current damage to the optic nerve, along with the amount of neovascularization present in the retina, the iris, and the anterior chamber angle.

From the above information, we can conclude that your glaucoma will progress in a manner that is different from other types of glaucomas. This is because your case involves neovascularization. As long as your central retinal vein occlusion remains controlled (95%), we can expect that the degree of neovascularization will be relatively low. However, some neovascularization still will occur. For this reason, your ophthalmologist will need to monitor it on a regular basis. If too much neovascularization is occurring, it may require the addition of another medication or use of a surgical procedure called panphotocoagulation to control it.

I recommend that you speak to your ophthalmologist about your concerns and the information that I have presented above. She or he knows your case better than anyone and can give you the best idea about what to expect in the future. It is essential that you follow your medication regimen exactly as prescribed by your ophthalmologist to ensure that your intraocular pressure remains controlled. Additionally, if your central retinal vein occlusion was caused by diabetes or high cholesterol (hypercholesterolemia) it is important that you follow your physician's instructions, including diet and exercise, to control these problems. This, in turn, will help to control the degree of neovascularization in your eyes.

Carolina Valdivia, MD

REFERENCE:

Pavan PR, Burrows BR, and Pavan-Langston D. Retina and Vitreous. In: Pavan-Langston D. Manual of Ocular Diagnosis and Therapy, 6th Ed. Philadelphia, PA: Lippincott, Williams and Wilkins, 2008:179-189.

Return from Neovascularization to Answer My Health Question