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Ask the Expert: Cataracts

Specialist Interview

Cataracts are a common issue affecting older adults, where cloudy patches form on the eye’s lens, growing to cause blurry vision and – if left untreated – blindness. As a measure of the prevalence of cataracts, it is the most commonly performed operation in the world – and has a very high success rate in improving eyesight. 

Mr Nikolas Koutroumanos is a subspecialty certified Consultant Ophthalmic and Oculoplastic Surgeon at St John & St Elizabeth Hospital. He is a qualified senior trainer in eyelid and cataract surgery and general ophthalmology. Here, he explains the causes, symptoms and effects of cataracts, as well as how they can be treated.

What is a cataract?

A cataract is the clouding of the natural crystalline lens that sits inside everyone’s eye. It takes its name from the Greek word for ‘waterfall’, and that is likely to do with the fact that, like in a waterfall, light no longer passes through a previously transparent structure. We are all born with a crystalline lens that is completely transparent, and as we grow older it very gradually becomes darker and more opaque, and that’s its way of maturing and getting older.

What causes cataracts?

Cataracts are something that will occur in almost everyone, assuming they live long enough. Different people get cataracts at different stages of their lives depending on genetics and certain other factors such as exposure to sunlight, diabetes, medications they are taking and so on.

What we are talking about here is involutional (age-related) cataracts. It’s also possible to get a traumatic cataract if someone injures their eye, regardless of their age. And some people – very uncommonly – are born with cataracts. You call this a congenital cataract.

What are the symptoms of cataracts?

It’s likely that people will have a cataract for some time without realising; it’s usually only when people start having symptoms that they get diagnosed. The symptoms are a very, very gradual deterioration of eyesight that typically manifests as a difficulty with reading small print. Other symptoms might include seeing halos or glare around lights when they’re driving at night, a gradual drop in long-distance vision and colours becoming less crisp.

Because it’s such a slowly progressing condition, people often miss the onset of the symptoms. It’s often only when removing the cataract by eventually having surgery that my patients realise what they have been missing out on – when they see a truly amazing improvement in vision after the operation. For example, people who are artistic, like to paint or do fine work, often find that cataracts become problematic, and they are some of the patients who get most excited when we fix it.

What are the treatments of cataracts?

In the early days of the lens changes that result from cataracts, updating one’s spectacles may help or delay the need for a cataract operation. But the only definitive treatment for a cataract is a cataract extraction operation.

What does a cataract operation entail?

It is not enough to diagnose the presence of a cataract. What is crucial is to receive an honest opinion about whether surgery at your current stage is indicated. Is the cataract at a stage where an operation would improve your eyesight? Once the discussion has been had about the risks and benefits of an operation, you have some lens calculations made using a type of eye camera to establish the sort of lens you can have.

The operation is a 10-15 minute surgery where the tiny lens in your eye is really gently aspirated with a microscopic ultrasound probe. Once this is done, a tiny artificial lens made of clear plastic – which has the same light-bending effect that your natural lens had when you were born – is inserted into position in your eye. The operation is carried out with anaesthetic drops and usually some sedation, and it’s so quick that patients often ask “when are you going to start?”, not realising that the operation has already finished!

Given that it’s the commonest operation performed in the world, it’s an extremely safe operation where the risk of complications are very, very low. Having said that, complications can take place and this is why a balanced and informed discussion needs to take place between every patient and their surgeon.

What is the recovery time from the operation?

Patients can expect to experience a slight dry-eye type sensation or a little discomfort immediately after the operation for a few days, but quickly after that things go back to normal in terms of discomfort. Meanwhile, vision tends to improve either immediately after the operation or within a couple of days.

As the most common surgical procedure in the UK, waiting lists are currently extremely long for cataract operations on the NHS. If you would like to be seen privately make an appointment with us by going to our website, emailing or calling: 020 7806 4000