Having cataract surgery

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Information for patients 

What is this information about?

This information is about what happens when you have surgery to remove a cataract from your eye, or eyes. 

It tells you how cataracts develop and how they are treated. It includes details of what happens before, during and after your surgery.  

Why have I been given this information?

You have been given this information to help you prepare for your cataract operation. It is important to read this carefully, so that you know what to expect and what to prepare for.   

You will be asked to give your consent (permission) for this operation. This information explains what you are agreeing to. You can use it to remind you if you have any questions to ask the team of people looking after you. 

It also gives you instructions about looking after yourself once you return home. Keep this information in a safe place, so that you can refer to it when you need to. You can share it with anyone living with you or looking after you.  

What is a cataract?

A cataract is clouding (also called opacity) of the lens inside the eye.  

Inside the eye, behind the coloured part (the iris) with a black hole in the middle (the pupil), is the lens. In a healthy eye, this lens is clear. It helps focus light rays on to the back of the eye (the retina), which sends messages to the brain allowing us to see.  

When a cataract develops, the lens becomes cloudy and prevents the light rays from passing through. Cataract surgery removes the cloudy lens and replaces it with a new clear artificial lens. 

What symptoms do cataracts cause?

Cataracts usually form slowly over years. This slowly causes the vision to become blurred. Over time, even wearing glasses does not help with this.  For some people, their vision can get worse quite quickly.  

A cataract can also cause glare, difficulty with night-time driving, and seeing multiple images in one eye. 

Do cataracts spread from eye to eye?

No. But often they develop in both eyes, either at the same time, or one after the other with a gap in between.

Are there different kinds of cataract?

Yes. Most cataracts are age-related, but other examples include: 

• congenital (you are born with them) 
• drug induced (for example, taking steroids) 
• traumatic (injury to the eye). 

Is there a link between diabetes and cataracts?

Yes. Cataracts are more common in people who have certain diseases such as diabetes.

Are cataracts just a part of getting old?

Most forms of cataract develop in later adult life. This is called an age-related cataract. It can happen at any time after the age of 40. The normal process of ageing causes the lens to gradually become cloudy. Not all people who develop a cataract need treatment. 

Can children have a cataract?

Yes, but this is rare.

I did not know that I had a cataract until my optician told me. Is that normal?

Yes. At first, you might not be aware that a cataract is developing, and it may not cause problems with your vision. Generally, as a cataract develops over time, your vision becomes blurred.  

In most cases, eyes with a cataract look normal. If the cataract is advanced, your pupil may no longer look black and can look cloudy or white.  

You may need to get new prescription glasses more frequently when the cataract is developing. Eventually, when your cataract worsens, stronger glasses may not work anymore. You might have difficulty seeing things even with your glasses on. 

How is my cataract assessed?

You will be asked about your sight problems, any other eye conditions, and your general health. Your vision will be tested and measurements taken with special equipment. This helps us recommend the best treatment for your vision problem. 

You will be looked after by a team of people including optometrists (opticians), nurses, technicians, doctors and surgeons.

When will I have my cataract treated?

In many cases, cataracts are harmless and may be left in your eye. If you feel that you do not have a problem with your vision or do not wish to have an operation, it is usually safe not to have surgery.  

When the cataract gets worse and starts to affect your daily life, even if you use up-to-date glasses, then cataract surgery may be the next step. Modern surgery works well for most people. 

As with all surgery, there are risks. Cataract surgery is done when you have a problem with your vision and you want to do something about it. 

Can anything be done to stop my cataract worsening?

No. There is no known way to prevent cataracts developing.

I have a cataract developing in both eyes. Are both operated on at the same time?

Most people develop cataracts in both eyes. The team in charge of your treatment will be able to advise you if having surgery on both eyes at the same time is right for you, as well as the risks and benefits.

There are two options: 

1. Your cataract surgery can be done on separate days.
2. Some patients choose to have both cataracts operated on the same day. This is called immediate sequential bilateral cataract surgery. Having both eyes operated on the same day means that you only have to come into hospital once, you only have one recovery period, and you only need one review after the operation.  

On the day of surgery, once the first eye cataract surgery is finished, the surgeon will do the surgery on the second eye. You will stay in the operating theatre the whole time, but the two surgeries are separate from each other. They use separate surgical instruments and equipment.  

What should I do before the surgery?

Pre-assessment staff will tell you what you need to prepare for the surgery. 

It is important that you remove all eye makeup, artificial eyelashes/glue
before surgery. This reduces the risk of infections.

Do I need any special tests before the operation?

Yes. You will have some special tests to work out the strength of the lens that will be placed in your eye. These tests are done before the operation day, either at your first clinic visit or during your booked pre-assessment appointment. 

Before your special tests, if you wear contact lenses, you must leave them out for the following time (unless told otherwise): 

• 1 week for soft lenses 
• 2 weeks for any types of rigid lenses, including gas permeable lenses. 

You may also have tests for your general health, such as blood tests and an electrocardiogram (ECG). 

I have had previous laser treatment to my eyes. Does it matter?

Yes. If you have had laser treatment, it is very important that you tell the doctors and nurses during your assessment.  

Some people have laser treatment (also called excimer laser treatment, for example LASIK or PRK) so that they do not have to wear glasses. This is most common in short-sighted younger people.  

Excimer laser treatment can affect how we calculate the strength of the lens placed in your eye. Even though we make an adjustment for the laser treatment, it is more difficult to select the right lens power. This may mean that you are at higher risk of being more, or less, long-sighted or short-sighted than planned after the cataract surgery.  

You may need glasses or contact lenses afterwards. Some people may need more laser surgery or surgery to their eye. Corrective surgery can sometimes be available on the NHS. 

What happens during the cataract operation?

In a cataract operation, the cloudy lens in your eye is removed and replaced with a new clear artificial lens. 

An experienced eye surgeon will carry out your operation or supervise a doctor in training who also performs surgery. Your eye is never removed and replaced during the operation. 

The most common cataract surgery uses a very small cut in the eye. The surgeon then uses a method called “phacoemulsification”, often shortened to “phaco” (pronounced “fay-ko”). This technique uses ultrasound to soften the lens. The lens is then broken up and flushed out using fine instruments and special fluids. 

A clear artificial lens (called an intraocular lens implant or IOL), made of a plastic-like material, is placed inside the eye. The back membrane of the lens (capsule) is left behind, and this holds the artificial lens in place. 

The wound is very small. Most people do not need stitches, although very fine stitches are sometimes needed to close the wound safely. This can occasionally cause some temporary irritation in your eye after the surgery.  

Depending on the type of stitch used, these may need to be removed. This is usually done in the clinic and is a quick and painless procedure.

Are cataracts removed by laser?

Lasers are not in routine use for cataract surgery except as part of research.  

There is new technology available that uses a specially designed laser for part of the procedure. The surgeon still needs to operate to complete the surgery because it is currently not possible to remove a cataract with a laser alone.  

What will I see, hear and feel during the operation?

You will be lying down on your back. Your face is partially covered by a sterile sheet. If you have difficulty lying flat or are claustrophobic, please tell the nurses this during your pre-operative assessment. We will do our best to make sure that you are comfortable before the operation starts. 

During the operation, the surgeon uses a microscope. The bright light from the microscope and the covering sheet means that you do not see the operation or the equipment being used, but you may see moving shapes.  

Usually, you will be awake during the operation and will be aware of a bright light, and often coloured lights and shadows. You may feel the surgeon’s hands resting gently on your cheek or forehead. 

A lot of fluid is used during the operation. Sometimes, fluid may escape under the sheet and run down the side of your face, into your ear or on your neck, which can be uncomfortable. 

You might hear conversations during the operation. These could be about the operation or for teaching or about other subjects. Please do not join in as it is important that you remain still during the procedure. 

What kind of anaesthetic will I have?

Most operations for cataract are performed under local anaesthetic. This means you are awake, but your eye is numb. This is usually given by eyedrops or an injection around your eye.  

A small number of people need sedation or a general anaesthetic, where you are asleep.

Will I have to stay overnight in hospital?

No. Cataract surgery is done as day-care surgery. This means you are admitted to hospital, have your operation and go home all in the same day. You could spend several hours in hospital from arrival to discharge.

Who will do my operation?

Your operation will be carried out by a qualified professional from the surgical team. Depending on the complexity of the procedure, it may be performed by a consultant, a specialist, a resident doctor working under direct supervision, or a senior resident doctor under indirect supervision. Whichever team member leads your surgery, a consultant is always available on-site to provide guidance and support if needed.

What are my choices for vision and glasses after the operation?

Your lens, which helps you focus, is removed during the operation and is replaced with an artificial lens, the intraocular lens implant.  

There is a choice of different strengths (powers) of lenses. These are just like different strengths of glasses lenses that affect how clearly you see when looking into the distance or when looking at near things like a book. 

During your initial assessment, the cataract team will discuss with you whether you want to have better focus for close vision or for distance vision. 

The different options include: 

1. Standard monofocal lenses

Most people choose to aim for good distance vision after the operation. 

If you choose this option, you will usually need reading glasses. You may still need glasses for fine focusing in the distance. Some people choose to aim for good close vision, especially if they like to read without glasses or do a lot of detailed close work such as embroidery. If you choose this option, you will need glasses for distance. 

2. Monovision 

If you had good vision in both eyes (with or without glasses), before the cataracts developed, monovision may be a good option for you. This means you will have good distance vision in one eye and good near vision in the other.   

Spreading the focus between the eyes in this way does not normally stop them working together or make you feel unbalanced. It helps you to do more activities comfortably without glasses. You will probably still prefer to wear glasses for at least some activities after surgery. It may take you a few weeks to get used to your new vision. 

Monovision may not be suitable for everyone. You should think about it carefully before you decide if it is right for you. 

3. Multifocal lenses 

Multifocal lenses are lenses that aim to correct vision for both near and distance.  

They are not available on the NHS. They cannot be purchased separately and implanted during your NHS operation. However, monofocal and multifocal lenses are made to the same high standards and are both safe for your eye. 

Multifocal lenses do not work for all patients and may cause some problems with your vision. If you are interested in having them, you will have to consult a private eye surgeon. 

3. Toric lenses

If you have a high degree of astigmatism we may offer you toric lenses to correct this. A toric lens is made from the same material as a standard lens. It is designed to correct astigmatism as well as replace the cloudy lens caused by a cataract. 

Astigmatism is an eye condition that many people have that can cause blurry vision. If you have astigmatism, it means your eye is shaped more like a rugby ball than a football, so light is focused at more than one place in the eye. 

The aim of giving you toric lenses is to improve your sight and reduce the need for glasses for seeing in the distance. As with a standard lens, you will still need glasses for reading and other close work. 

You do not need a toric lens if you are happy to wear glasses for distance vision. Toric lenses may not be suitable if you have other eye conditions as well as cataracts and a high level of astigmatism. 

The operation is much the same as standard cataract surgery. After the toric lens is put into the eye, the surgeon turns it into the correct position. This positioning needs to be very exact. A standard lens does not need such exact positioning. 

What possible problems are there with toric lenses?

As with all surgery, there are some risks and limits to the results. 

• A toric lens may not fully correct your astigmatism. You may still need glasses for distance vision. 
• If there are problems during cataract surgery, it may not be possible to put in a toric lens. 
• The lens can move out of position after surgery. If this happens, you may need a second operation to move it back into the correct position. This carries the added risks of further surgery. 
• Some people may need another operation to remove the toric lens and replace it with a standard lens. 

Other options

If you have a high level of astigmatism, other options include:

• glasses 
• contact lenses 

Laser eye treatment can also correct astigmatism, but this is not available on the NHS.

How accurate are the results of cataract surgery?

Your surgeon will have chosen a lens implant which gives the best results for your eyes. But everyone responds differently to surgery so it is impossible to guarantee how accurate the results will be.  

Sometimes people will need moderately strong glasses after surgery even though their vision was carefully measured before, and the surgery went well. 

Please remember that cataract surgery is performed to remove the cataract, not to remove the need to wear glasses.

Will I see colours differently?

A cataract in your eye scatters and absorbs blue light selectively. After surgery, your lens implant is very clear so a change in how you see colour is common. This can be quite a strong change, especially just after surgery. It can make colours look brighter or bluer than usual. 

Most lens implants have ultra violet (UV) blocking built in, but you can use sunglasses when you are outdoors in bright sunlight to block UV light reaching the retina.  

If you have a job where colour vision is critical, you should seek specific advice. 

Do cataract operations have any complications?

There is an extremely small risk of vision loss to the other eye.  

Serious complications are uncommon but, if they occur, they can cause permanent damage to your eye and your vision. These risks include: 

• 1 in 1,000 risk of severe and permanent vision loss in each eye. 
• Approximately 1 in 250,000 risk of severe and permanent vision loss in both eyes with immediate sequential bilateral cataract surgery. 
• About 1 in 100 risk of needing more surgery to correct a problem for each eye. 
• 1 in 20 operations have less serious complications. These may need further treatment, either at the time of surgery or following the operation for each eye. 
• 1 in 10 patients need laser treatment at some time in the future for opacity (clouding) of the capsule behind the implant. 

What should I look out for after the surgery?

Symptoms which mean you should contact us include: 

• Increasing redness, pain, blurred vision or yellow or green discharge. These can be signs of a serious infection or inflammation. 
• Blurred central vision. This may mean that you have something called macular oedema (water logging of the central part of the retina). 
• Red sore eye after stopping drops. This can happen if inflammation of the eye returns after surgery.  
• Distorted vision: the implanted lens can move from its original position. This causes distorted vision, though this is unusual. If this happens, you might need further surgery to reposition the lens. 
• A shadow, lights or floaters in your field of vision: It is quite common to see a shadow or flickering lights in your side (peripheral) vision after surgery. This is because light is being focused slightly differently on the back of the eye (the retina) by your new lens implant. 

You may become aware of a shadow to the side of your vision, often described as a ‘half-moon’ or ‘crescent’. This is called negative dysphotopsia. It is usually temporary as your eye adapts to the new lens. 

Will my eye be covered after the operation?

Your operated eye will be covered with a protective clear plastic eye shield. Some patients may additionally have an eye pad. If you leave hospital with a pad you will be told when to remove it yourself and when to start to put in your eye drops. Most patients are advised to wear the protective plastic eye shield when sleeping for around 1 week.  

If we do cataract surgery on both eyes on the same day, we will put a clear plastic shield in front of each eye, but you may choose to remove one shield.  

How soon after the operation do I go home?

After the operation, you will have a chance to have a drink and a snack before the nurse or doctor checks with you that you are ready to leave.  

The nurses will check that you have your aftercare instructions and eye drops and then discharge you from the hospital. This usually takes 30 to 60 minutes. 

How will my eye feel after the operation?

As the anaesthetic wears off, there can be a dull ache or a sharp pain like something in the eye, felt in and around your eye. Your eye will also be red, watery and your vision may be very blurred.  

You can ask the nurse for tablets for pain relief. You may want to use your usual painkillers when you get home and during the first 24 hours. Your eye usually settles over two to four weeks after the operation although for some people this can take slightly longer. 

A slight feeling of grittiness or as if there is something in your eye can last several months after the operation, as the small wound gradually flattens. 

You should contact us if the pain, redness or blurred vision is getting worse rather than better. 

How do I put in the eye drops?

A nurse will teach you how to look after your eye. You will be shown how to clean your eye and put in the eye drops correctly. Follow the instructions below.

1. Tilt your head back. 
2. Gently pull down your lower lid of your eye with one hand. 
3. Look up and allow the drops to fall inside lower lid. 
4. Do not let the tip of the bottle touch your eye. 

In some circumstances, family and friends will be taught how to do this so they can help you. The eye drops help reduce the risk of inflammation after surgery. They may be necessary for one to two months.

Is there anything else I have to do to care for my eye?

Do not rub or touch your eye. This is extremely important in the first week or two after the operation. 

Do not wear eye makeup for at least one week after your surgery. 

You might find you are sensitive to light, so it is useful to have a pair of plain dark glasses in case you need them. You can buy these at any chemist or supermarket. The medical and nursing staff will advise you if there are any activities you should avoid. 

Most people can start normal physical activity again within a day or two. You should be able to return to work the day after your operation, depending on your job.  

If you perform manual work, or a job which requires a lot of use of the eyes, you might need longer. The doctors and nurses in clinic will advise you. Your eye will take a few weeks to settle. 

When can I wash my face and hair after the operation?

For one week after surgery: 

• Be careful when washing. Do not directly splash water into your face in the shower. 
• Do not put your head under the water in the bath. 
• Use a clean face cloth.  

When can I see my optician for an update to my glasses?

You can usually have your eyes checked for new glasses by your own optician about four to six weeks after the operation. 

You will be advised about tests for glasses to improve vision (refraction) at your clinic appointment after the operation. 

While you are waiting for your new glasses, or between your first and second eye operations, you may notice some vision problems. This is more likely if there is a large difference in prescription between your two eyes. 

During this time, you can choose whether to wear your old glasses. You may also ask your optician to remove one lens from your glasses until your final pair is ready or until both eye operations are completed. 

Can the cataract return?

No. But you can develop a thickening or clouding of the membrane behind your new lens implant in the months or years following your surgery. This happens in about one in 10 cataract surgery patients. This is called posterior capsular opacification. It causes your vision to blur.  

This can be treated with a simple laser procedure carried out during an outpatient visit. This is called a YAG laser capsulotomy. The treatment is usually quick, painless, and very effective. It can occasionally cause complications such as retinal detachment or waterlogging in the central part of the retina.  

The risks of YAG laser treatment are smaller than the risks of the original cataract surgery. This will be explained at your consultation. 

Who can I contact if I would like any further information or have any concerns after I have read this information?

This information is based on information about cataract surgery produced by Moorfields Hospital and used with their kind permission.