Vitreous Detachment
The vitreous is the clear gel that fills the central cavity of the eye. At a young age, the vitreous is very thick with a consistency somewhat like uncooked egg white. As a natural process of aging, the vitreous becomes more liquefied. As the vitreous becomes progressively liquefied, it begins to move around inside the eye. Eventually, the vitreous becomes so loose that it "pulls away" from the retina. This is called "vitreous detachment" and is a result of a natural process of aging. Some people have vitreous detachment in their 30's or 40's but usually it occurs after age 50.
The vitreous is the clear gel that fills the central cavity of the eye. At a young age, the vitreous is very thick with a consistency somewhat like uncooked egg white. As a natural process of aging, the vitreous becomes more liquefied. As the vitreous becomes progressively liquefied, it begins to move around inside the eye. Eventually, the vitreous becomes so loose that it "pulls away" from the retina. This is called "vitreous detachment" and is a result of a natural process of aging. Some people have vitreous detachment in their 30's or 40's but usually it occurs after age 50.
Floaters
As the vitreous detaches from the retina and falls away into the centre of the eye, it can cause 'floaters' in your vision. These appear as dots, spots or curly lines that appear suspended in front of you and move with your eye.
Flashes
Flashes of light are also a common symptom of a vitreous detachment. These are due to pulling on the retina as the vitreous separates. If a retinal blood vessel is broken from the pulling, a vitreous haemorrhage can occur. The patient may see a small amount of blood as a shower of spots. Larger haemorrhages can cause large dark blobs in the visual field or an overall decrease in vision.
Retinal Tears
If the vitreous is abnormally adherent to the retina or the retina is weak in a certain area, a retinal tear can occur as the vitreous separates and pulls away from the retina.
As the vitreous detaches from the retina and falls away into the centre of the eye, it can cause 'floaters' in your vision. These appear as dots, spots or curly lines that appear suspended in front of you and move with your eye.
Flashes
Flashes of light are also a common symptom of a vitreous detachment. These are due to pulling on the retina as the vitreous separates. If a retinal blood vessel is broken from the pulling, a vitreous haemorrhage can occur. The patient may see a small amount of blood as a shower of spots. Larger haemorrhages can cause large dark blobs in the visual field or an overall decrease in vision.
Retinal Tears
If the vitreous is abnormally adherent to the retina or the retina is weak in a certain area, a retinal tear can occur as the vitreous separates and pulls away from the retina.
Retinal detachment
This occurs when liquid vitreous passes through the break and goes under the retina. The retina will then start to detach from the underlying tissue. Since most breaks occur in the far peripheral retina, the detachment will first cause loss of a portion of the side vision. This can be seen as a curtain or dark shadow involving the peripheral vision. As the detachment extends towards the macula, the shadow will also enlarge. Central vision will be lost if the macula detaches. Without surgical repair, most detachments will eventually involve the entire retina and all vision will be lost.
When the retina detaches, it separates from the back wall of the eye and is removed from some of its blood supply and source of nutrition. The retina will degenerate and lose its ability to function if it remains detached. Central vision will be lost if the macula remains detached.
This occurs when liquid vitreous passes through the break and goes under the retina. The retina will then start to detach from the underlying tissue. Since most breaks occur in the far peripheral retina, the detachment will first cause loss of a portion of the side vision. This can be seen as a curtain or dark shadow involving the peripheral vision. As the detachment extends towards the macula, the shadow will also enlarge. Central vision will be lost if the macula detaches. Without surgical repair, most detachments will eventually involve the entire retina and all vision will be lost.
When the retina detaches, it separates from the back wall of the eye and is removed from some of its blood supply and source of nutrition. The retina will degenerate and lose its ability to function if it remains detached. Central vision will be lost if the macula remains detached.
Fortunately, the great majority of vitreous detachments do not cause a retinal tear. Sometimes a PVD can occur without any symptoms and sometimes there can be lots of annoying symptoms without any retinal breaks.
Treatment
If a retinal tear is discovered before a detachment occurs, it can be treated to prevent retinal detachment. Usually laser is used to treat a retinal break. The laser creates a series of welds surrounding the break seal the retina to the underlying tissue. This prevents fluid (liquid vitreous) from passing through the break and detaching the retina. Rarely, the laser cannot be used and then a retinal cryoprobe is used to treat the break. The cryoprobe creates a freezing reaction to produce scarring around the break.
Treatment
If a retinal tear is discovered before a detachment occurs, it can be treated to prevent retinal detachment. Usually laser is used to treat a retinal break. The laser creates a series of welds surrounding the break seal the retina to the underlying tissue. This prevents fluid (liquid vitreous) from passing through the break and detaching the retina. Rarely, the laser cannot be used and then a retinal cryoprobe is used to treat the break. The cryoprobe creates a freezing reaction to produce scarring around the break.
Once a detachment occurs, it is almost always too late to use the laser or cryoprobe. This is why it is so important to be examined promptly if you have symptoms (flashes, floaters, shower of spots). The vitreous can continue to separate and pull on the retina for several weeks or longer and the retina can develop a tear during this time. Even if a tear is discovered and treated, follow-up examination is necessary, to be sure the laser reaction is working and that no additional tears have developed. Not all retinal breaks need to be treated. Many people have round or atrophic holes in their retina that are discovered on routine examination and usually, these do not need to be treated. In general, however, if a retinal break is discovered in association with new symptoms of a vitreous detachment or there are other high risk factors for a retinal detachment (family history, very near-sighted, retinal detachment in the other eye, history of eye trauma, prior cataract surgery etc), treatment is indicated. Treatment of retinal breaks with the laser or cryoprobe is very successful and retinal detachment can usually be avoided.
