A choroidal neovascular membrane is a severe complication that occurs with several eye diseases. Among the most common conditions to lead to a choroidal neovascular membrane are age-related macular degeneration, Best’s disease, and degenerative myopia.
A choroidal neovascular membrane forms when there is a break in the basement membrane of the retina and new blood vessel growth occurs in this area. These new blood vessels can break or rupture leading to bleeding beneath the retina. The treatment for a choroidal neovascular membrane is using an injection of medication to stop the growth of the new blood vessels.
Where a CNVM Forms
A choroidal neovascular membrane, or CNVM, forms in the basement membrane layer of the retina.
This layer is called the retinal pigmented epithelium and contains Bruch’s membrane at the base.
This layer of the retina is responsible for providing a means for transporting waste out of the retina and has many blood vessels running within it.
If there is a break in Bruch’s membrane, there is a potential to develop new blood vessels within the break and create a choroidal neovascular membrane.
Symptoms of a Choroidal Neovascular Membrane
Symptoms that may be experienced with a choroidal neovascular membrane can include blurry vision, distortion in the center of vision, and a loss of areas within the center of the vision.
A choroidal neovascular membrane typically forms in the center of the retina called the macula.
This area creates both the best vision and the central vision.
Since the center of the vision is impacted, any changes such as hemorrhages or blood vessel growth will create noticeable changes in the vision.
Causes of CNVM
The most common underlying cause of a CNVM is age-related macular degeneration.
With macular degeneration, the retinal pigmented epithelium is weakened over time, and a build-up of calcium deposits called drusen will form in the macula.
As the retinal pigmented epithelium is weakened, the potential for a break in Bruch’s membrane increases greatly.
Another cause of a choroidal neovascular membrane is Best’s disease. This is an inherited retinal dystrophy that creates a buildup of yellow-colored deposits composed of protein and fat in the retina.
Best’s disease usually progresses slowly until the age of fifty, at which point the amount of buildup in the retina is excellent enough to damage the retina and lead to a choroidal neovascular membrane.
A less common, but still prominent, cause of a choroidal neovascular membrane is high myopia.
Myopia, or nearsightedness, is a common refractive condition that is usually corrected with glasses or contact lenses.
However, when the amount of myopia is very large, anatomical changes begin to occur.
The length of the eye is increased and causes stress and stretching on the back of the retina.
This stretching can thin Bruch’s membrane and lead to a higher risk for a choroidal neovascular membrane.
Treatment for CNVM
The only approved treatment for a choroidal neovascular membrane is an injection into the eye of a medication called anti-VEGF.
This class of medications prohibits the growth of new blood vessels within the retina.
By reducing the growth of new blood vessels, the neovascularization will slowly recede and allow the choroidal neovascular membrane to heal.
Our optometrist at Eye Contact in Acworth, GA excels in the prescription of glasses, contact lenses and the diagnosis of various eye diseases. Call our optometrist at (770) 529-1925 or schedule an eye exam appointment online if you would like to learn more about a choroidal neovascular membrane. Our eye doctor, Dr. Wes Mobley provides the highest quality optometry services and eye exams in Acworth, Georgia and its surrounding areas.
