Posterior Vitreous Detachment

A posterior vitreous detachment (PVD) is a rather dramatic event in the normal aging process of the human eye, usually occurring during the sixth and seventh decade of life.

The vitreous is the jelly like material that fills the large central cavity of the eye. It is 98% water with the remaining portion being fibrous proteins that give it a stiff consistency similar to double strength gelatin or egg white. The vitreous is tightly connected to the retina, which is the light sensitive layer in the back of the eye.

As we age, there is a separation of the watery elements from the fibrous components. In essence, the vitreous is “melting” and shrinks. Vitreous shrinkage continues and results in part of the vitreous actually becoming detached or peeled away from the back of your eye. This is called a posterior vitreous detachment (PVD). Traction on the retina is responsible for the characteristic "flashes" or streaks of light which often accompany PVDs. The "floaters" frequently reported are from the reorganization of the fibrous elements as well as from some fragments of retina which may have been dragged into the vitreous cavity by this separation.

It is important that all eyes with recent onset of flashes and floaters be examined carefully by an optometrist. Most of the time nothing unusual is found, and simple reassurance is all that is needed. The flashes eventually go away, and the floaters diminish and become less bothersome with time. Up to 20% of eyes with a vitreous detachment may develop a tear or hole in the retina. If untreated, retinal tears or holes can continue to worsen and severe vision loss can result due to a retinal detachment. A retinal detachment is a very serious sight threatening condition requiring a major surgical procedure to repair. Even in the best of hands, the result of this procedure can be very unpredictable.

If retinal tears are found, treatment is simple and very effective! Repair is done either by spot welding several circles of burns around the tear with a laser or by sealing it with a freezing unit. Both accomplish the same purpose with good results and low complication rates. The procedure is done as an outpatient under a local anesthetic.

When symptoms appear, it is important to examine the eye with dilation within days of their onset. Changes can occur rapidly, and time can be of the essence if a retinal detachment is present. If all is normal in the first eye, when the second eye is affected, one should not assume that all will be well. The second eye also should be carefully examined and the retina treated if necessary.