If you have noticed cloudy, hazy, or “misty” vision after cataract surgery or lens replacement surgery, it is natural to look for explanations. Two causes that are commonly discussed are:
Posterior capsule opacification (PCO) — sometimes called a “secondary cataract”
Intraocular lens (IOL) opacification — clouding of the implanted artificial lens itself
This article explains the difference in plain English and suggests practical questions you can ask at a review appointment.
Important: This page provides general information only and is not medical advice. Seek urgent medical care if you experience severe pain, sudden vision loss, flashes, floaters, or a red, painful eye.
After cataract or lens replacement surgery, most patients expect clearer vision. When vision becomes cloudy again, it can be worrying and confusing. Several conditions can cause similar symptoms, which is why careful examination and accurate diagnosis are important.
Two of the most commonly discussed causes are PCO and IOL opacification.
During cataract or lens replacement surgery, the natural lens is removed, but a thin transparent membrane called the posterior capsule is usually left in place. This capsule helps support the implanted lens.
Over time, this capsule can become cloudy. This is known as posterior capsule opacification (PCO).
PCO may cause:
blurred or cloudy vision,
glare or halos around lights,
reduced contrast or faded colours.
PCO is sometimes referred to as a “secondary cataract,” but this can be misleading. The original cataract has not returned; instead, the supporting capsule has become cloudy. PCO is common and can develop months or years after surgery.
PCO is often treated with a short outpatient procedure called a YAG laser capsulotomy.
The laser creates a small opening in the cloudy capsule, allowing light to pass through more clearly and improving vision. The procedure is usually quick and painless.
Whether YAG laser treatment is appropriate depends on examination findings and individual circumstances. Not all causes of cloudy vision after surgery will improve with YAG treatment.
IOL opacification refers to clouding of the implanted artificial lens itself. This is different from PCO, although the symptoms can overlap.
Patients may describe:
a gradual reduction in visual acuity,
persistent haze not improved by glasses,
glare or halos, particularly at night,
difficulty reading or driving in different lighting conditions.
Other eye conditions can cause similar symptoms, which is why careful assessment is essential. Accurate diagnosis helps ensure that the most appropriate management plan is considered.
Although PCO and IOL opacification can produce similar symptoms, they are different conditions and may require different management approaches.
In general terms:
PCO may be treated with YAG laser capsulotomy.
Lens-related issues or other causes may require monitoring, further investigation, referral, or, in some situations, discussion of lens exchange.
You may find it helpful to prepare questions in advance.
Is my reduced vision due to PCO, IOL opacification, or another cause?
What findings support that conclusion?
If you are unsure about your diagnosis or options, it is reasonable to request copies of your medical records.
You may ask for:
implant details (lens model and serial or batch information, if recorded),
follow-up notes and test results (visual acuity, refraction, imaging),
copies of correspondence about advice and treatment plans.
Requesting records is not a criticism of any clinician. It is a sensible step to help you understand your care and make informed decisions.
Legal advice may be appropriate if, after appropriate assessment and record review, you remain concerned about your care.
These may include:
whether you were properly informed of risks and alternatives,
whether follow-up and investigation were appropriate,
how ongoing symptoms or complaints were managed.
Any potential claim is fact-specific and depends on medical evidence and independent expert opinion.
If you are experiencing cloudy vision or reduced acuity after cataract or lens replacement surgery and would like advice on practical next steps, NJS Law can review your circumstances and advise accordingly.
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