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Cataracts are cloudy areas that develop in the lens of the eye. A normal lens should be clear. However with cataracts, there is a gradual change in the structure of the lens in the eye, slowly making it more and more cloudy.

In a normal eye, light is focused by the cornea and the lens to form a sharp image on the retina at the back of the eye. As we get older, the lens can become hazy. This makes the vision rather blurred or hazy even when wearing the correct spectacles.

There are different types of cataracts

Age-related cataract (senile cataract)

This affects older people and is by far the most common form of Cataracts. In the UK about 1 in 3 people over the age of 65 has a cataract with men and women being equally at risk. Often both eyes are affected, though one eye may be worse than the other.

Age-related cataract often form gradually over many years. As the effects are gradual, many people with an early stage cataract do not realise they have it as the initial cloudiness may not be noticeable. In some people, the cataract does not become too severe, but in many cases, vision becomes gradually worse over the years.

Congenital cataracts (present at birth)

These are uncommon but it is important that they are diagnosed early. Vision and seeing has to be learnt very early in infancy. A congenital cataract stops the eye from learning to see and can cause blindness that can may persist even if the cataract is removed later in life. It is vital for a congenital cataract to be removed as early as possible after birth. Doctors examine the eyes of babies as part of routine baby checks.

Other types of cataract

Other uncommon causes of cataracts can stem from an injury to an eye, or as a result of radiation exposure. Cataracts can sometimes develop as a secondary problem for people with conditions such as diabetes or people with other eye conditions.

Causes of age-related cataracts

The cause is of senile cataracts is still not fully understood, though it appears to be a change to the make up of the proteins in the lens. One theory is that there is a disturbance of fluids and nutrients getting into the lens as you get older. This may then result in some of the proteins clotting together within the lens, causing small, cloudy areas to appear. As these deposits build up, light passing through the retina is partially blocked, affecting your vision. The severity of the cataract depends on the number of cloudy areas that develop in the affected lens.

Most affected people develop a cataract for no apparent reason. Some factors may increase the chance of developing cataracts. These include:

  • Smoking
  • Diabetes
  • Having a poor diet
  • Steroid medicines
  • Excessive exposure to UV light from the sun or tanning beds
  • Having a family history of cataracts

Symptoms of age-related cataracts

At first you may notice your vision becomes blurred a little. With time, you may notice some of the following:

  • Spots in your vision
  • Seeing halos around bright lights – e.g. street lights
  • Not being able to see as well in brightly lit rooms or in sunshine
  • Your colour vision may begin to fade
  • Over the years your vision may gradually become worse and is unable to be corrected by glasses

Depending on the severity of the cataract, the effects can range from slightly blurred vision to complete blindness in the affected eye.

Diagnosis Of Age-Related Cataracts

A cataract is normally easily detectable by a doctor or optometrist during an eye examination.

Sometimes an early cataract is detected during a routine eye check, before you have noticed a problem with vision.

Treatment for age-related cataracts

An early cataract may not cause any noticeable problem with your vision, but the rate of decline varies from person to person. It is common for people to have their cataract treated in the early stages if it is affecting their ability to function normally, e.g. reading the paper, driving, cooking etc. Treatment is usually successful.

Cataracts cannot be treated with medicines, eye drops or lasers. The only way to treat cataracts is with an operation. Around 300,000 cataract operations are performed in the UK each year. The operation involves removing the cloudy lens and replacing it with an artificial plastic lens or intraocular implant. This routine operation usually takes 10-20 minutes and can often be performed as a day case.

Cataract operations

Typically one eye is operated on at a time and in most cases it is performed under local anaesthetic. This means that you are awake during the operation but it is not painful because local anaesthetic eye drops are used to numb your eye. The operation is performed with a microscope through a very small opening in the eye. Once the eye is numb, the surgeon makes a tiny hole in the front of the eye at the edge of the cornea. A tiny thin instrument is then pushed into the lens through the front part of the lens capsule. Ultrasound waves are emitted to break up the contents of the lens within the lens capsule.

The content of the lens is then removed by suction. Once removed, a clear plastic lens is inserted in its place through the tiny hole made in the front part of the eye. Usually, the incision is small enough that no stitches are needed. You may have to wear a pad over your eye afterwards.

A standard plastic lens has no focusing capability glasses will still need to be worn if you did before the operation. It is sometimes possible to have an accommodating lens which allows near and distant focusing. Your surgeon will be able to discuss this in more detail if these are suitable for you.

Contact us

Our Appointments Team have a dedicated and caring approach to finding you the earliest appointment possible with the best specialist.

If you do not have a GP, then we have an in-house private GP practice that you can use. Alternatively we can suggest the most appropriate course of action for you to take, given your location and individual circumstance.

If you have medical insurance (e.g. Bupa, Axa PPP, Norwich Union), you will need to contact your insurer to get authorisation for any treatment and, in most cases, you will require a referral letter from your GP.

For the next available cataract appointment you can contact us by emailing londoneyeunit@hje.org.uk or by calling our team on 020 7078 3848

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Patient information

Our Hospital is renowned for providing exemplary levels of care across more than 90 services. From orthopaedics, to urology, ENT, as well as a private GP practice and our urgent care centre, Casualty First, our services are led by some of London’s leading Consultants. For more information, and to find a service suitable for your care, find out more about the services that we offer.

Make an enquiry

If you have any questions relating to treatment options or pricing information then get in touch with us by filling out one of our contact boxes or giving us a call on 020 7078 3848.

Our Appointments Team have a dedicated and caring approach to finding you the earliest appointment possible with the best specialist.

 If you are self-paying you don’t need a referral from your GP for a consultation. You can simply refer yourself* and book an appointment.

If you have medical insurance (e.g. Bupa, Axa PPP, Aviva), you will need to contact your insurer to get authorisation for any treatment and, in most cases, you will require a referral letter from your GP.

If you do not have a GP, then we have an in-house private GP practice that you can use. Alternatively we can suggest the most appropriate course of action for you to take, given your location and individual circumstance.

*Please note – for investigations such as X-rays and MRI’s a referral will be required. However, we may be able to arrange this for you through our on-site private GP.

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