YAG Laser Capsulotomy

Yag capsulotomy is a laser treatment used to improve vision after cataract surgery, and is done in the outpatient clinic.

Clouding of the part of the natural lens covering (the capsule) that remains after cataract surgery is the commonest thing to need attention afterwards, and the longer anyone follows a group of patients the more of them have needed the laser. It is not a complication and not a sign anything has gone wrong.

This membrane may become cloudy and cause blurred vision, and sometimes people will see streaks or haloes around lights. This can occur several months or even years after surgery. It tends to worsen with time.

YAG laser treatment can be done without anaesthetic or any cut in the eye. The laser is applied to the clouded posterior capsule and creates an opening that allows light to pass though uninterrupted and create clearer vision.

After the laser treatment, there is no special care required; no patch; no restrictions. Because dilating drops are used before the treatment you probably won’t feel comfortable to drive until the drops have worn off, which may take a few hours.

Benefits

Yag capsulotomy is performed to open the clouded part of the membrane and improve vision.

Risks

Some people may develop new floaters after this procedure.

Sometimes the pressure in the eye can go up in the short term – this is only an issue if you already have damage from glaucoma in which case extra treatment may be advised after the laser. This is the commonest thing to happen after the laser. How often it is reported varies enormously between studies, from under 1 in every 100 to as many as 30 in every 100, which tells you more about how closely different researchers looked than about your own eye. It is usually short-lived and settles with drops, and it is more likely when a larger opening is made or more laser energy is used.

Rarely, the laser treatment needs to be repeated.

Small marks on the lens implant itself are commoner than people expect – something like 1 in every 10 – where the laser touches the lens rather than the capsule behind it. They almost never affect the vision.

Less common risks include:

• Swelling of the centre of the retina (macular oedema) – about 1 in every 100
• Inflammation inside the eye, which is usually brief; it persists in about 1 in every 100
• Displacement of the intraocular lens
• Migration of vitreous gel to a position in front of the intraocular lens

What about retinal detachment?

For a long time this was genuinely unsettled, and older versions of this page said so. It is now reasonably clear, and the answer depends on which cataract operation you had.

The concern came from studies of extracapsular cataract surgery, the larger-incision operation that was standard until the 1990s. In those eyes the laser did carry a real extra risk of retinal detachment – one large population study put it at around three times the background rate.

A review published in 2022 pooled eleven studies covering more than 65,000 eyes. It confirmed the increased risk in eyes that had had the old extracapsular operation – about three times – but found no detectable increase in eyes that had had modern phacoemulsification, which is what essentially everyone has now, and none in European patients.

I would put it like this: the risk was real with the old operation and has not been shown with the current one. That is not quite the same as proving it is zero, and if you are short-sighted, have lattice degeneration, or have had a detachment in the other eye, you already carry a higher background risk that the laser does not remove. Those are the people I am most careful with.

What happens when I come for YAG laser?

You will see the nurse who will check the vision (bring your long distance, driving or TV glasses if you use them); you will have some drops put in the eyes to make the pupil large; after the drops have worked – usually about 30 minutes – we will check you need the treatment and if you do ask you to sign a consent form.

If both eyes need treating we can usually do them at the same visit, and often do. It is common to have obvious clouding in one eye and a moderate amount in the other, and there is nothing to be gained by making you come back a second time.

For the treatment itself: you will put your chin on a slit lamp – similar to the machine we normally use to examine your eye. You will be asked to keep both eyes open and we find a way to keep your eyes steady, usually by getting you to stare at something with the other eye. A light is used so that the surgeon can see the lens capsule. You may hear or even feel 20-40 “pops” or clicks as the laser is used.

That’s it!