Laser vitreolysis explained

An in-clinic laser aimed at breaking up a floater

Laser vitreolysis uses a finely focused laser to break a floater into smaller pieces, or to vaporise it, so that it casts less of a shadow on the retina. It is carried out in the clinic rather than an operating theatre. There is no cut and no injection, and it is done while you sit at a machine much like the one used for a routine eye examination.

It is sometimes offered as a middle path between simply living with a floater and undergoing surgery. It is important, though, to be realistic about which floaters it can help and what it can achieve.

Focused pulses aimed at the floater itself

The laser delivers short, focused pulses of energy to the floater. The aim is either to break it into fragments small enough to drift out of the line of sight, or to reduce it so that it interferes less with vision. The surgeon must be able to see the floater clearly and target it safely, keeping the laser well away from the delicate structures around it.

Best for a single, well-positioned floater

Laser vitreolysis works best for a single, well-defined floater sitting in clear space, comfortably away from both the lens at the front of the eye and the retina at the back. The classic example is a Weiss ring, the ring-shaped floater that can appear after a posterior vitreous detachment. When a floater is discrete and well positioned like this, it can be treated more safely and with a better chance of benefit.

It reduces floaters rather than removing them

The treatment is far less useful for diffuse, cloud-like floaters, or for floaters lying close to the retina, where treating them safely is difficult. It is better thought of as a way of reducing a floater than of reliably removing it. Results vary from person to person, more than one session is sometimes needed, and some people notice little difference. It is not a guaranteed cure, and it does not suit every floater or every eye.

Generally low in experienced hands, but real

In experienced hands the risks are generally low, but they are real and worth understanding. The laser can raise the pressure inside the eye, it can damage the lens and bring on a cataract, and it can injure the retina. Rarely, it can lead to a retinal tear or detachment. These risks are part of why the treatment is chosen carefully and only for suitable floaters.

Not a routine treatment, and the evidence is limited

Laser vitreolysis is not offered routinely in the UK. The evidence for it is limited and mixed, and many specialists remain cautious about how much it helps and in whom. For most people with floaters, the sensible path is to allow time and let the brain adapt, and for the small number who are genuinely disabled, vitrectomy is the more definitive, if more invasive, option. You can see how the choices compare on the floater treatment options page.

Know the symptoms that are separate from ordinary floaters

Whatever you decide about treatment, it is worth knowing the symptoms that need urgent attention. A sudden shower of new floaters, flashes of light, or a shadow or curtain across your vision can be a sign of a retinal tear or detachment, and should be assessed the same day. These are quite separate from the long-standing floaters that laser is sometimes used for.