Posterior Vitreous Detachment (PVD)
As we age, the vitreous changes. It becomes less solid and more liquid-like. It shrinks and pulls away from the back of the eye. The vitreous is attached to the retina by millions of microscopic fibers. When enough of these fibers break, the vitreous separates completely from the retina, causing a PVD.
The retina is composed of nerve tissue at the back of the eye that transmits light signals to your brain. Different parts of the retina are responsible for different parts of vision. The small central part of the retina, or the macula, is responsible for central vision and fine detail. The larger outer areas of the retina are called the peripheral retina, and are responsible for peripheral or side vision. The large cavity of the eyeball between the retina (in the back of the eye) and the lens (in the front of the eye) is filled with the vitreous body, a gel-like fluid that attaches to the retina.
For most people, a PVD is a benign (harmless) event with no symptoms and no vision loss. Others may notice a lot of floaters. Some with PVD will have the following symptoms:
flashes of light in peripheral or side vision
floaters, or tiny specks, moving around in your field of vision
or rarely, decreased vision or a dark curtain or shadow moving across your field of vision
For a small amount of people having a PVD, problems occur when the vitreous detaches from the retina. The vitreous pulls too hard from the back of the eye and takes a piece of the underlying tissue (the retina) with it. This is called a retinal tear. It an lead to a retinal detachment, which can cause permanent loss of vision.
Diagnosis and Testing
Most people don’t know they are having a PVD. But if you notice a lot of floaters or flashes of light suddenly, or have a decrease in vision, see your ophthalmologist as soon as possible. These symptoms can be normal, but they can also mean that you have a retinal tear or retinal detachment. You won’t be able to tell the difference but an ophthalmologist can. If a retinal tear or retinal detachment is treated early enough by an ophthalmologist, you can save your vision.
A dilated examination is necessary to diagnose any signs of posterior vitreous detachment, retinal holes and tears, and retinal detachments. Additional testing helps an ophthalmologist diagnose and monitor these conditions.