Flashes, floaters and retinal tears
What are flashes and floaters and why are they important?
To help understand this question it is important to first understand the anatomy of the eye. The inside of the eye is filled with the gel-like substance called the vitreous. The vitreous has a jelly like consistency when we are young and is firmly attached to the front of the eye on the inside (called the vitreous base). The retina is the thin photosensitive tissue that lines the inside of the eye cavity like wallpaper. When we look at something, the retina acts like the film in a camera and captures the image. the vitreous is firmly attached to the retina at the vitreous base (anteriorly) and the macular and optic nerve (posterior over the rest of the retina). It is lightly attached. Over time, the vitreous gradually becomes thinner and more liquid. It eventually collapses (like a collapsed spiderweb) and separates itself from the retina. This is a normal age-related process and is called a posterior vitreous detachment (PVD). PVD’s are typically harmless and cause increased floaters in the eye. In some cases, however, the traction on the retina may create a tear. Retinal tears frequently lead to retinal detachment’s as fluid seeps underneath the retina, causing it to separate and detach the outer layers of the eye.
Floaters are insoluble proteins situated within the vitreous cavity. They are usually a normal part of aging. A sudden onset of floaters needs to be reviewed by an eye specialist to rule out other, more rare causes and consequences.
Are all floaters a sign of a problem?
No. Many people experience floaters when they are young and without having a PVD. These floaters are just condensation is of the protein gel in the eye. They float in the cavity of the eye and cast tiny shadows on the retina. Floaters are more likely to develop as we age and more common in people who are nearsighted, have diabetes, or who have had a cataract operation.
There are other more serious causes of floaters, including infection, inflammation (uveitis), haemorrhaging, retinal tears and injury to the eye. In most cases floaters are part of the natural ageing process and simply an annoyance. They can be distracting at first, but eventually tend to “settle” at the bottom of the eye, becoming less bothersome.
They usually settle below the line of sight and do not go away completely. Most people have floaters and learn to ignore them; they are usually not noticed until they become numerous or more prominent. Floaters can become apparent when looking at something bright such as white paper or a blue sky.
I have been diagnosed with a retinal tear. How is this treated?
If you develop a retinal tear it should be treated with laser to create a scar adhesion between the retina and the outer layers of the eye. Laser uses light to create heat at the spot where it is focused. The heat burns the tissue which heals as a scar, adhering the tissues together. The retinal function in the areas of the laser is lost because the tissue is destroyed. Remember that the area of the retinal tear is already not functioning as a result of the tear and that the tiny blind spot caused by the laser is only minimally larger. The laser treatment helps to prevent a subsequent retinal detachment in the vast majority of cases.
What do I watch out for after laser treatment of my retinal tear?
Any sudden increase in floaters could signify another tear and should be assessed. Any loss of peripheral vision (like a shade or curtain being drawn from your peripheral vision towards your central vision) may be a cause of retinal detachment and needs to be assessed promptly.
Will laser treatment for a retina tear treat my floaters?
No. Laser treatment creates a scar around the retinal tear, but does not do anything for floaters. For people who have floaters that are simply annoying, no treatment is recommended. Floaters can rarely be so dense and numerous that they significantly affect vision. Usually with time these will settle down and be acceptable. In very rare cases, a vitrectomy operation may be needed. This operation removes the vitreous gel, along with its floating debris, from the eye. The vitreous is replaced with a balanced salt solution. Surgery is not recommended unless the floaters seriously interfere with vision.
If you have any concerns, please call the practice at 021-671 5154
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