Posterior vitreous detachment

Many retinal detachments are associated with posterior vitreous detachment (PVD), a common condition in which the vitreous gel shrinks and separates from the retina.

Posterior vitreous detachment usually results from normal, age-related changes in the vitreous gel, although it can also result from eye injury or inflammation caused by surgery or disease. PVD most commonly is seen in people age 60 and older. But it may begin to occur as early as about age 40, and it becomes increasingly common after age 50.

As you age, the vitreous gel in the middle of your eye begins to change. The gel's normal structure breaks down in a process called syneresis. Parts of the gel shrink and lose fluid. The fluid collects in pockets in the middle of the eye, and thick strands of the gel form and drift through the eye. These strands appear as floaters.

Sometimes these changes cause the vitreous gel to shrink suddenly and separate from the retina. This is called posterior vitreous detachment.

Posterior vitreous detachment usually does not cause any problems, but it can sometimes cause tears in the retina. At points where the vitreous gel is strongly attached to the retina, the gel can pull so hard on the retina-a process called traction-that it tears the retina. The tear then allows fluid to collect under the retina and may lead to a retinal detachment.

The main symptoms of PVD are floaters and flashes of light. It is important to pay attention to these symptoms. A sudden change in these symptoms could be a warning sign of a retinal tear or detachment.