Posterior Vitreous Detachment (PVD)

The eye is filled with a clear jelly-like substance called the vitreous gel, which as we age, becomes waterier, less jelly-like and isn’t able to keep its usual shape. As a result, it begins to move away from the retina at the back of the eye. This natural change is called a PVD. PVD is not a sign of a disease or eye health problem. For most of us a PVD happens naturally as we get older.

Floaters

Floaters can take lots of different forms and shapes and can come in different sizes. You may see them as dots, circles, lines, clouds, or cobwebs. Floaters usually move around in your eye and you may find floaters are more obvious in bright light or on a sunny day.

They often appear when the vitreous in the main part of the eye gets older. A floater is created when the vitreous becomes waterier and smaller, harmless clumps of cells develop and float in the vitreous inside the eye.

The light rays, which normally travel from the front of the eye, meet a clump in the vitreous and it casts a shadow on the retina at the back of the eye. We see this shadow as a floater.

Floaters will become less obvious or go away with time, or your brain will learn to ignore them. Floaters are very common, and many people have floaters even if they do not have PVD or an eye condition.

Symptoms of a PVD

PVD can cause symptoms such as floaters, little flashes of light, or a cobweb effect across your vision. The degree of symptoms varies from person to person.

Small flashes of light can be visible when the vitreous pulls away from the back of the eye. The movement of the vitreous away from the retina at the back of the eye creates a tug on the retina. The retina reacts by sending a small electrical charge to your brain. You see this as short, small, flashes of light. These differ from the visual disturbance which can occur with migraine.

Importantly, these same symptoms can be an indication of a more serious problem, such as a retinal tear, which needs urgent attention.

You will not be able to tell the difference between floaters and flashes caused by PVD or retinal detachment. The only way you can tell is to have your eyes examined by an ophthalmologist or optometrist. If you suddenly experience any of the following symptoms, make sure you have your eyes examined as soon as possible – preferably on the same day or within 24 hours. Please call us for advice if you are concerned:

A sudden appearance of floaters or an increase in their size and number
Flashes of light and/or a change/increase in the flashing lights you experience
Blurring of vision
A dark ‘curtain’ (or lace-curtain effect) moving up, down or across your vision