The inside of the eye is filled with a clear, jelly-like substance called VITREOUS. Because it is clear, light rays are able to pass through it to reach the retina. However any change in the consistency, color, or structure of the vitreous can interfere with the transmission of light to the retina and thus can cause visual symptoms.
Vitreous undergoes certain changes which are associated with the normal aging process. In young people, the vitreous fills the entire inner cavity of the eye and has a solid, jelly-like consistency. With age, this consistency becomes less jelly-like and more liquid, and the vitreous begins gradually to pull away from the retina. This pulling away is called POSTERIOR VITREOUS COLLAPSE.
When the vitreous begins this “pulling away”, condensations within the jelly are formed and are called FLOATERS These can be seen as small dots that are “floating” in the field of vision. If these floaters are small and infrequent specks or threads, usually they are of no concern. However, if they are large or web-like and come in showers, they may indicate that a retinal tear has occurred or that there is bleeding within the eye. In this case, an ophthalmologist should be consulted.
Another symptom associated with posterior vitreous collapse is PHOTOPSIA. This term refers to flashes of light which appear in the side vision and which usually can be seen in a darkened room. Infrequent light flashes are associated generally with the normal aging process. A sudden onset of frequent light flashes, however, could indicate that the vitreous is putting traction on the retina, which could result in a retinal tear. How can the vitreous cause a retinal tear
In some areas, the vitreous may adhere stronger to the retina than in others. In these areas of what is called VITREORETINAL TRACTION, the bond between vitreous and retina may be so strong that instead of the vitreous collapsing away from the retina, the retina tears at the point of adherence. Pre-existing retinal problems also could make the retina more susceptible to tears. Some tears caused by vitreoretinal traction do not generate ocular symptoms.
However, the onset of constant floaters and frequent light flashes can be warning signs that a retinal tear has occurred.
Most retinal tears occur within the first three months after, but not necessarily immediately after, the onset of symptoms. As a precautionary measure, during this period of time it is wise to avoid strenuous physical activity, bending over, lifting heavy objects and active sports.
Posterior vitreous collapse occurs in most people between the ages of 50 and 70. It is part of the normal aging process and, in most people, causes no damage to the eye. Whereas 15% of the total population may develop symptoms that are associated with this condition – floaters and light flashes – only 1 % of these people develop retinal tears or holes. Can this condition be treated?
Treatment of retinal tears or holes is successful in most cases. To seal the affected area, the surgeon uses either argon laser photocoagulation or a freezing method called cryopexy. If the retina becomes detached, then a major surgical procedure is required.