Monday, December 13, 2010

Posterior Vitreous Detachment

Posterior vitreous detachment is a common eye condition in which the vitreous humor detaches from the surface of the retina. It occurs in about 75 per cent of people over the age of 65. The eyeball is filled with the vitreous humor, which is a jelly-like substance. There are millions of fine fibers intertwined within the vitreous that are attached to the surface of the retina. As we age, the vitreous slowly shrinks, and these fine fibers pull on the retinal surface. Usually the fibers break, allowing the vitreous to separate and shrink from the retina. This is a vitreous detachment.

The symptoms of vitreous detachment are flashes of light, known as photopsia, a sudden dramatic increase in the number of floaters, and a ring of floaters or hairs just to the temporal side of the central vision. Sudden detachment of the vitreous from the macular area usually causes the person to see flashes and floaters. The flashes may look like lightning or electric sparks, and the floaters may look like threads or specks. Symptoms may last days to weeks.

There is no specific treatment for vitreous detachment. Usually people find that the symptoms calm down after about six months and people do eventually get used to living with the floaters. The brain tends to adapt to the floaters and eventually is able to ignore them, so they only become a problem in very bright light. Posterior vitreous detachment does not in itself cause any permanent loss of vision. The visual acuity should remain the same as it used to be before the posterior vitreous detachment started.