Floating Spots / Flashing Lights

Seeing small gray “blobs” that float across the vision could be a sign of a posterior vitreous detachment.  

The vitreous is a clear substance within the eye, which has a gel-like consistency. It fills the hollow space between the lens and the retina at the back of the eye. The vitreous helps maintain the shape of the eye, it absorbs shock and it helps keep the retina in contact with the back wall of the eye.

With ageing the vitreous can become liquified and as a result it can pull away or separate from the retina and collapse into the central hollow space of the eye. This is known as a posterior vitreous detachment (PVD) and it is a normal ageing process.

What are the risk factors for posterior vitreous detachment?

  • Ageing
  • Trauma: knock to the head or eye can cause an early onset PVD
  • Nearsightedness (myopia)
  • PVD in the other eye

What are the symptoms of posterior vitreous detachment?

The symptoms can include:

  • Floaters: These may appear as hundreds of small spots or objects (e.g. cobwebs, squiggly lines) “floating” in the field of vision. These floaters may be black, grey or clear in colour.
  • Lightning flashes: These may appear as a “sparkle”, “streak” or “twinkle” across the vision.
  • Decreased vision

The symptoms of a posterior vitreous detachment can often present similar to a retinal tear (or early detachment) or the PVD itself can lead to a retinal tear so it is important to see an ophthalmologist within 24-48 hours of your symptoms presenting to check the health of the retina.

What is the treatment for a posterior vitreous detachment?

If the posterior vitreous detachment has occurred without associated retinal tears, treatment is not required.  While in the early days, floaters and flashes can be very annoying, with time these symptoms will usually become less and less noticeable. Most people do not require treatment. For floaters that persist and continue to interfere with vision, treatment is possible, either with laser or more often, surgically.