What are floaters?

Floaters are small pieces of debris that 'float' in the vitreous humour of the eye. They occur behind the lens (the transparent window through which light enters the eye), and in front of the retina (the light sensitive tissue that lines the back of the eye).
Vitreous humour is a clear, jelly-like substance that fills the space in the middle of the eyeball. It is 99% water and 1% substances that help to maintain the shape of the vitreous.

What do floaters look like?
Floaters appear in the front of the eye, and can occur in a number of different shapes and sizes. For example, they may appear as:

• tiny black dots,
• small shadowy dots,
• larger 'cloud-like' spots, or
• long, narrow strands.

Floaters occur in the vitreous jelly of the eye, which is usually clear. Floaters cast shadows on to the retina and it is the shadows that someone who has floaters is able to see.
Floaters most commonly develop as your eyes get older, as part of the natural ageing process.
Will floaters affect my vision?
Floaters are harmless and will not usually interfere with your vision. Sometimes, you may have floaters without noticing them. This is because your brain constantly adapts to changes in your vision, and learns to ignore floaters so that they do not affect your vision.

Symptoms:
If you have floaters, you may not notice them all the time. When your eyes are still, or you are gazing into space, you may see them drift slowly across your vision.
Floaters are usually grey and semi-transparent. They may move when you move your eyes. When you move your eye to look in different directions, the floaters may appear to move quickly.
However, floaters do not tend to follow your eye movement precisely, and they will often seem to dart away as you try to look directly at them.

Floaters occur in a variety of forms
Floaters can occur in a variety of different forms. They may appear as:

• dots,
• circles,
• lines,
• cobwebs, or
• other shapes.

You may notice lots of small floaters in your field of vision, or just one or two larger ones.
Most floaters are small and quickly move out of your field of vision. Larger floaters can be distracting and make activities that involve high levels of concentration, such as reading or driving, difficult.
Floaters are often most noticeable when you are looking at a clear-coloured background, such as a white wall or a clear sky.

Natural debris
The large area in the middle of your eyeball is filled with a clear, jelly-like substance called vitreous humour. As you get older, the vitreous humour can become less firm and strands of a protein called collagen may become visible within it. The collagen strands may appear to swirl as your eye moves.
Normally, light travels through the clear layer of vitreous humour in order to reach the retina. The retina is the light sensitive layer of cells and tissue at the back of your eye which transmits images to your brain via the optic nerve. Any objects, such as floaters, that are in the vitreous humour will cast shadows on to the retina.

Posterior vitreous detachment (PVD)
Posterior vitreous detachment (PVD) can be the result of changes that occur to the vitreous humour of the eye, as the eye gets older. PVD is a common condition that occurs in about 75% of people over 65.
With age, the central part of the vitreous humour becomes more liquid, and the outer part, known as the cortex (which contains more collagen) starts to shrink away from the retina. Floaters develop as a result of the collagen thickening and clumping together.
As well as floaters, flashing can be another symptom of PVD. Flashing may occur when the outer part of the vitreous humour pulls on the light sensitive tissue of the retina. The pulling stimulates the retina, causing your brain to interpret it as a light signal. This creates the sensation of flashing lights.

Floaters and flashes, if you experience them it is important that you seek immediate medical advice from your Optometrist, family Doctor or a local hospital Eye Department.