Flashes and Floaters are very common, but there is no way of knowing if you have a retinal tear without a proper dilated retinal examination.
What is Posterior Vitreous?
As we get older, the gel in the middle of eye, known as the vitreous, starts to degenerate and break down; a process known as posterior vitreous detachment or PVD. As this occurs, opacities can form within the gel, which cast a tiny shadow on the back of the eye or retina. These shadows are what we see as floaters, and they can take many shapes – spots, lines, squiggles etc. As these floaters are sitting in the vitreous gel, when we move our eye the floaters move around the gel, and therefore seem to move around in front of our vision. While these floaters can be annoying, they do tend to become less noticeable over time.
As the vitreous degenerates, it also collapses towards the centre of the eye. In some people, the vitreous has firm attachments to the surrounding retina, and when it collapses, exerts traction on the retina. This traction irritates the retina, producing what is perceived as a flashing light.
Are Flashes and Floaters Dangerous?
In most cases, the attachment between the retina and vitreous will separate, usually over a few weeks, and the flashing lights will stop. In a small percentage of people however, the vitreous does not separate from the retina, and instead pulls on the retina and produces a tear in the retina. This is important as the tear provides an access point for fluid in the vitreous to pass through the tear, and go under the retina, producing what we call a retinal detachment. A retinal detachment is an urgent sight threatening condition, which needs to be treated with surgery relatively quickly.
Fortunately if a tear is detected, a retinal detachment can be prevented by performing laser around the tear. By creating a barrier around the tear, laser prevents fluid from being able to get under the retina.
What should I do if I get Flashes or Floaters?
Flashes and Floaters are very common, but there is no way of knowing if you have a retinal tear without a proper dilated retinal examination. If you have flashes and/or floaters, it is important to see your ophthalmologist as soon as possible for a full retinal check.
What is a Vitreous Detachment?
The inside of the eye is filled with a gel like substance which helps maintain its shape, known as the vitreous. The vitreous attaches onto the surface of the retina through millions of fine fibres. As we age the vitreous begins to shrink and slowly pulls away off the retina. Sometimes the fibres break, allowing the vitreous to detach and shrink from the retina. In most cases a vitreous detachment, also known as a posterior vitreous detachment, is not sight-threatening and requires no treatment.
Vitreous detachments can lead to retinal tears and retinal detachments. If left untreated, these conditions can potentially lead to permanent vision loss in the affected eye. This happens rarely, (approximately 1 in 20 people with Posterior Vitreous Detachment).
You will notice a retinal tear as an increase in flashes, floaters or a curtain. If this occurs, you should return immediately. Otherwise you will usually be rechecked approximately 4-6 weeks later to ensure there are no retinal tears.
Who is at risk of vitreous detachment?
Those more at risk of a vitreous detachment are typically people over the age of 50 and especially those over the age 80. People who are short -sighted also have increased risk of suffering vitreous detachments.
What are the symptoms of a vitreous detachment?
The most common symptom associated with a vitreous detachment is small but sudden increase in floaters. Floaters appear as dark cobwebs or stringy specks that float about in your vision. They are caused by strands in the vitreous that cast tiny shadows on your retina. The increase in floaters may also come with flashes of light in your peripheral or side vision. Most of the time you will not notice a vitreous detachment or you will merely find the increase in floaters a nuisance.
How are vitreous detachments detected?
A comprehensive dilated eye examination is the only way to detect a vitreous detachment. If the vitreous detachment has led to macular hole or detached retina, early treatment can help prevent the loss of vision.
How can a vitreous detachment be treated?
There is no current treatment for a vitreous detachment. Usually the symptoms calm down and people eventually get used to having the floaters.
If I get a tear how is it treated?
Retinal tears are treated to prevent retinal detachment. Laser is used to “seal” around the tear and prevent it spreading. The laser can sting a little and is very bright. It is almost always to the peripheral retina and so has no effect on the central vision.