Cataracts

A cataract occurs when the normally transparent lens in your eye gradually becomes cloudy. The lens is responsible for focusing light onto the retina at the back of the eye, which in turn transmits the image to the brain. A cataract blurs the vision as the light is no longer clearly focused on the retina and vision gets worse, particularly for distant objects. It can become difficult to recognize people across the street, see television clearly or drive, particularly at night.

What causes Cataracts?

Most cataracts are slow growing and a natural consequence of the aging progress due to exposure to UV from the sun, smoking and poor nutrition. These risk factors increase the number of free radicals in the body. These free radicals disrupts the linkage of proteins in the lens of the eye. These proteins are arranged in a regular array in the healthy eye, allowing transparency. Cross linkage causes the proteins to clump together causing loss of transparency. This is like the white of an egg that is clear when raw, but once cooked the protein denatures and becomes opaque. About half of patients aged 65 to 75 have some degree of cataract and the incidence increases with age - it has been said that if we live long enough, all of us will get cataract to some degree. Most patients over the age of 80 have cataracts that affect their vision to some extent. Poor nutrition, smoking and UV radiation are all factors that hasten cataract formation because they increase the number of free radicals in the body. Cataracts can occur from other causes for example through head trauma, and certain metabolic illnesses such as diabetes. Rarely, cataracts are present at birth.

What are the symptoms of Cataract?

A cataract causes the vision to deteriorate fairly slowly, often in one eye more than the other although both eyes will almost always be affected eventually. Patients often complain of filmy vision, experience ghosting of their sight and sometimes double vision in the affected eye. The vision can vary day to day and in different lighting; bright sunlight can cause problems with glare, which may need tinted or photochromic lenses to help alleviate the problem. Conversely it is often difficult to read in dull illumination. Sometimes the developing cataract can make the spectacle prescription change as the lens becomes denser. In such cases, called nuclear cataract, the problem can often be managed for a significant time by adjusting the spectacles prescription on a regular basis.

Can I do anything to stop my cataracts getting worse?

There is evidence that UV damage is cumulative and therefore a high annual exposure to sunlight hastens cataract development. We therefore recommend that good sunglasses are worn. If you wear spectacles for distance vision driving or out of doors, prescription sunspectacles are recommended with a good UV blocking lens will help. Recent research has shown that the use of NAC (N-acetyl-carnosine) may help in combination with Pure Focus Lutein spray. Link to NAC How can my cataracts be treated? Early cataract management means ensuring that the spectacle prescription is accurate and increasing the light when reading or using magnifiers may help for a while. Self treatment with NAC (see above) may be beneficial. Cataract surgery should be considered if the reduced vision is affecting day to day life. There is no longer a need for the cataract to be ?ripe? before treatment. The surgical treatment is to remove the cloudy lens and replace it with a clear intraocular lens (IOL). This IOL needs no care and cannot be felt or seen once it is in place. It remains as a permanent part of the eye. Should cataracts occur in both eyes, they will not be treated at the same time, but one eye, usually the worse affected, will be operated on first. The other eye can then be treated a few months later. This is to minimise the chance of a post operative infection spreading from one eye to the other.

How long will I have to stay in hospital?

For most patients cataract removal is done under local anaesthetic as Day Case surgery which means no overnight stay in hospital. Your consultant ophthalmologist will discuss with you the best treatment in your particular case.

How long does the operation take?

Most patients are suitable for small incision (phacoemulsification) surgery which takes 20-30 minutes. For some patients, depending on the complexity of the operation and any other eye disease, it can be longer. What happens after the operation? The eye may be uncomfortable and possibly gritty but there is normally no severe pain. Normal analgesics (pain killers) are usually all that are needed for pain relief. The pupil will be dilated for the first 24hours and so dark spectacles will help with any light sensitivity. Vision may remain slightly blurred. Occasionally patients experience double vision until the local anaesthetic wears off. Normally the cataract is removed with such a small incision that a patient can return to normal day to day activities the next day, including reading, watching TV and light exercise ( walking etc) Strenuous exercise and heavy lifting should be avoided for 2-4 weeks.

When can I go back to work?

A clerical job may be resumed after 2-3 days. Manual work may be resumed after 2-4 weeks - your consultant will advise on specific jobs.

Is cataract surgery safe?

All surgical procedures carry an element of risk. Cataract surgery has a high success rate with over 90% of patients achieving a satisfactory outcome. The vision achieved will, of course depend on any other factors which are affect the health of the eye in a particular individual, for example co-existing age related macular degeneration (AMD) What are the possible complications of surgery? The possible complications of cataract surgery include: * Posterior capsule thickening (see below) * Post-operative infection * Haemorrhage in the eye * Clouding of the cornea * Swelling of the macula (back of the eye) * Retinal detachment Serious problems are uncommon and can mostly be treated successfully.

What is the most common complication of cataract surgery?

When a cataract is removed, the transparent capsular bag which supports the lens is left in place. In 15-20% of eyes, this capsular bag thickens and becomes less transparent and the vision begins to cloud over again. Some patients worry that the cataract is growing back. This cannot happen, and the capsule thickening can be treated by laser in an outpatient procedure. Posterior capsule thickening can occur usually within the first 2 years of surgery, often within 6-12 months. If you have any concerns about you vision in the months or years after surgery, consult the optometrist who referred you and they will be able to examine you for capsule thickening and refer for treatment.

How long after the operation must I wait until I can have my eyes tested and new spectacles prescribed?

After 3-4 weeks, as long as there have been no complications, you will be asked to see the optometrist (optician) who referred you for a follow up appointment. At this time, adjustments to your spectacle prescription can be made. Sometimes the vision has improved so much that only reading spectacles are required. I use bifocal/varifocal spectacles at the moment - will I still be able to do so after the operation? Yes, normally that is not a problem. Occasionally, patients have such a big difference in the prescription between the eyes that this is no longer possible, but the optometrist will tell you if that is likely to be a problem in your case.