The retina is the curved back layer of the eye and is covered in light sensitive cells. Light enters the eye through the pupil and is focused by the cornea and the lens so that a crisp picture can fall on the retina. Information is then relayed to the brain via the optic nerve.
When a person has a detached retina, it means the retina has separated from the back of the eye. Without treatment, retinal detachment may worsen until the retina is completely detached and unable to send information down the optic nerve to the brain. This results in blindness. Around one in 10,000 people are affected by some degree of retinal detachment. Older people are at increased risk.
The effect on eyesight depends on the location and severity of the detachment – a detachment at the area of central vision (the macula) will have a more significant impact on the vision than a detachment in any other area of the retina.
A range of complications
The outlook is promising
The success rate of treatment for this condition is high, with around nine out of 10 retinas able to be reattached. Sometimes, a second operation may be needed. After treatment, the person’s vision may improve over subsequent months, but often some vision loss is permanent. A change of prescription glasses is usually required.
FLASHES & FLOATERS
Flashes and floaters are very common symptoms that are important because they can be the warning signs of a retinal detachment. It is important to note that the vast majority of patients with flashes and/or floaters do not have a problem that requires treatment.
Flashes are spontaneous flashes of light, which typically occur in the side vision. They are often noticed at night, whilst lying in bed.
Floaters are small spots that appear in front of the vision that can be of varying shapes and sizes. Sometimes they are small, like a fly or mosquito, sometimes they appear as a hair hanging down or as a fine cobweb. They are usually grey and transparent, and follow the vision wherever you look. Floaters in themselves are not dangerous. They do not grow larger or obscure the vision. Most people over the age of 50 have floaters. Most either consciously or subconsciously ignore them. If you are lucky they will float out of the way. There is an operation that can remove them but it is generally accepted that the risks associated with this type of operation do not warrant it being done for a minor symptom like floaters.
Flashes and floaters occur in the vitreous of the eye, which is a clear jelly that occupies most of the space in the back of the eye. As you get older it will start to collapse in places. This will start earlier if you have trauma, shortsightedness or inflammation inside the eye. When the jelly degenerates it leaves floaters in front of the vision. This is called a posterior vitreous detachment. Sometimes as the vitreous collapses it will pull on the retina and cause a flash of light. The flashes are temporary and typically subside over 1 to 3 months, decreasing in intensity and frequency.
Most patients with floaters and/or flashes do not have a problem that requires treatment. However, the eyes do need to be examined thoroughly by an ophthalmologist to exclude any retinal damage. If you are reassured that there is no damage, then typically you will be re-examined in 4 to 8 weeks time to make sure this has not occurred subsequently. Your eye doctor should promptly check any sudden onset of flashes or floaters or additional symptoms such as loss of side vision.
If a retinal hole is identified it usually needs to be dealt with quickly. If it is left unattended it can develop into a retinal detachment and vision loss. If the hole is small then it can usually be repaired with a laser in the rooms.
Symptoms of retinal detachment should be assessed by an eye specialist promptly.