Approximately 20–30% of patients who have cataract surgery will develop posterior capsule opacification (PCO) within 2–5 years. This happens when cells from the old lens gradually migrate and proliferate on the back of the capsule — the thin membrane that was left in place during cataract surgery to support the new implant. The result is exactly the same as cataract: gradually blurring, glare, and reduced contrast sensitivity. The good news is that treatment is quick, painless, and performed as an outpatient in a single visit.
What is posterior capsule opacification?
During modern cataract surgery (phacoemulsification), the cloudy lens is removed but its capsule — an extremely thin membrane — is left intact. This capsule cradles the new intraocular lens implant in its correct position.
Over the months or years following surgery, residual epithelial cells can multiply on the back surface of this capsule, causing it to become hazy or wrinkled. This is PCO, sometimes called 'secondary cataract' (a slight misnomer, as the original cataract cannot return once the lens has been removed).
Symptoms
- Gradual blurring of vision — may feel like the cataract has come back
- Glare and halos around lights, particularly at night
- Reduced contrast and colour vibrancy
- Difficulty reading or with fine detail work
The YAG laser capsulotomy procedure
Treatment is YAG (yttrium-aluminium-garnet) laser capsulotomy — a quick, painless outpatient procedure performed in the clinic.
- Dilating drops are applied to widen the pupil.
- You sit at a slit lamp; a contact lens is placed on the eye to focus the laser.
- The laser creates a small, precise opening in the central posterior capsule — taking just a few minutes.
- The procedure is completely painless. You may see flashes of light and hear clicking sounds.
- Most patients notice improved vision within 24 hours. Final visual improvement is usually apparent within a few days.
After the procedure
- You will be asked to wait 30–60 minutes post-procedure to have your eye pressure checked (a small IOP rise is the most common side effect and is usually temporary).
- Avoid driving on the day of treatment due to dilating drops.
- Most patients return to normal activities the following day.
- Anti-inflammatory drops are sometimes prescribed for a few days.
How long does the improvement last?
YAG capsulotomy is a one-time, permanent treatment. The opening created in the capsule does not close. Once done, PCO does not recur at the treated site and the procedure does not need to be repeated.
Frequently Asked Questions
Is YAG laser capsulotomy covered by the NHS?
If your original cataract surgery was performed on the NHS, YAG capsulotomy for the resulting PCO should be available on the NHS. If your cataract was performed privately, the YAG procedure is typically covered as part of the surgical aftercare by your surgeon's practice. Standalone private YAG capsulotomy is also available for patients who had their original surgery elsewhere.
How soon after YAG capsulotomy will my vision improve?
Most patients notice improvement within 24 hours. If vision does not improve as expected within a week, follow-up with your surgeon is worthwhile to ensure there are no other contributing factors (such as macular disease or dry eye).
Can YAG capsulotomy cause retinal detachment?
A small increase in lifetime retinal detachment risk following YAG capsulotomy has been documented in the literature — roughly a 0.1–1% additional risk. This risk is higher in patients who are very short-sighted (high myopes). Your surgeon will discuss this with you and advise you to report any new floaters, flashes or visual shadow promptly after the procedure.
Mr Mohamed Mohyudin
MBChB BSc MSc FRCOphth CCT — Consultant Ophthalmic Surgeon, Spire Elland Hospital, Yorkshire. GMC 7039600.
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