Consultant Ophthalmologist,
Cataract & Refractive Surgeon

BMedSci BM BS MRCS MRCSEd MRCOpth FRCOphth MMedLaw PgD Cataract & Refractive Surgery

Cataracts - Frequently Asked Questions

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How does the eye work?

Light rays enter the eye through the cornea (the clear window right at the front of the eye). After they pass through the cornea they are focussed by the lens onto the retina at the back of the eye. The amount of light entering the eye is regulated by the pupil (the dark gap in the coloured iris).

I think I have a cataract what do I do?

You need to arrange to be assessed at your local eye unit. An optometrist is a good first port of call but you can also be referred to us by your GP. There are sadly many causes of poor vision and cataract is only one of them, albeit a common one. Your ophthalmologist will be able to tell you whether it is indeed a cataract which is causing your problem. We will be able to advise you as to the problem with your vision and what we can do for you.

I have been told I have a cataract what do I do?

You really need to decide whether you want to have anything done about your cataract. When you see us we need to discuss the difficulties you are having with your vision and how these affect your daily life and activities. 

I am a firm believer that we should not try and fix something that isn’t broken. If you are perfectly happy with your current vision then you should probably stay as you are. Just because you have a cataract it does not mean that you automatically require surgery. Of course we can discuss this with you face to face and go through the pros and cons of surgery.

If you have any concerns then you should arrange to be referred to an ophthalmologist so we can answer all of your questions. If your poor vision intereferes with your life and we confirm that a cataract is present and that it is the main cause of your poor vision, then we can consider surgery for you.

Do you offer one-stop private cataract surgery?

Yes. If you are insured or you’re paying out your hard earned money you want the best possible service.  If you are seen privately elsewhere you attend for your initial consultation and then you have to still wait for your surgery.  Often you have to return to the Hospital in between to have some more tests and eye scans.  This can be frustrating.

The One-Stop Cataract Service takes away all the to and fro.  You are seen, assessed by Mr Alwitry, and then operated on by him the very same day.  Often your initial appointment is around midday and you are on your way home by 3pm.  No having to book back in for surgery and risk cancellations, diary clashes etc.  A smooth, efficient and professional service.

My vision is blurred, what can I do?

You need to arrange to be assessed at your local eye unit. An optometrist is a good first port of call but you can also be referred to us by your GP. There are sadly many causes of poor vision and cataract is only one of them, albeit a common one. Your ophthalmologist will be able to tell you whether it is indeed a cataract which is causing your problem. We will be able to advise you as to the problem with your vision and what we can do for you.

If your vision went blurry gradually then there is no urgency about being seen. If however your vision went down rapidly (over a single day or so) then your problem may be more urgent – see your GP or optometrist as soon as you can and they can decide what to do.

I am due to have cataract surgery, what sort of pre-operative assessment will I have?

We need to ensure that you are medically fit for the surgery and also need to take certain measurements of the eye to work out what sort of procedure we should do for you and what power lens we should implant. Cataract surgery is mostly done under local anaesthetic and so you do not need to be particularly fit or healthy to have it. We do however need to optimise your medical status before we proceed. For example if we find that your blood pressure is very high then we may need to refer you to your GP to get it lowered before we go ahead with surgery. 

Your health and safety is my primary concern and I will not rush into surgery if it puts you at any avoidable risk. Sometimes however we cannot get you completely fit and healthy and we have to proceed anyway. 

Your lens (the one that has turned into a cataract) was responsible for focussing the light on the back of the eye. If you are short sighted then it focussed the light from close objects accurately on the retina. If you are long sighted then light from distant objects was focussed correctly. If we are taking your lens out and putting a new synthetic one in then we have the opportunity to change the focussing power of the eye. We can decide to keep you long or short sighted or (even better) we can put a lens in which allows you to see in the distance clearly without needing your spectacles. You will however still need reading spectacles in the majority of cases.  

In order to work out what power lens we should put in we need to take several measurements of the size and shape of the eye (one size does not fit all). We use a special machine which uses a non-contact completely pain free way to take these measurements. Sometimes if we cannot get a good scan we will use an ultrasound to take the appropriate measurement.

What will happen on the day of surgery?

You will attend the hospital and book in for your surgery. It is important that if you have had any change in your medical condition or if you notice a problem with the eye we are due to operate upon (for example redness or stickiness) you must let the staff know immediately as this may impact upon whether we may proceed safely with surgery.

The staff will fill in the documentation about you and confirm some of the information you have provided previously. They will check your consent form and make sure that everything is signed and in order.

You will be seen pre-operatively by me (or your chosen surgeon) and you will have an oportunity to ask any questions you want. A mark will be placed on your forehead and you will have a wrist band with your details placed upon your wrist. Depending upon where you have your operation there may be a delay until you have your surgery. We undertake several operations (between 5 and 8) on a morning or afternoon list and you may be the first or you may be the last – pot luck I’m afraid!

You will have numerous drops put into the eye we are due to operate on – they sting unfortunately. These drops will dilate your pupils so that we can do the surgery safely and effectively

You will be taken to theatre when your slot comes up. After a few more checks – to check that we are operating on the correct side and you are who we think you are – we will give you your anaesthetic.

What sort of anaesthetic will I have and do I have a choice?

We tend to use local anaesthetic for all of our cataract procedures. There are two main techniques we use. One is using a blunt ended tube to inject anaesthetic around the eye (called sub-Tenons anaesthesia) and the other is to use just drops (called Topical anaesthesia).

There are benefits and downsides to each.

  1. Sub-Tenons: Your eye is frozen with drops so you cannot feel anything. You then look up and out and we pass the cannula around the side of the eye through a small incision in the conjunctiva (the filmy clear bit at the front of the eye). The anaesthetic will be injected and you may feel a bit of pressure and a bit of stinging. This stinging only lasts a few moments and is a good indicator that it is working. After that the eye is completely numb. An added benefit is that the eye cannot move and, because the anaesthetic affects the optic nerve too, the vision is dimmed so you cannot see anything that is happening.
  2. Topical: You only have drops to numb the eye. During the procedure you will have to look up into a bright light and you will also have to keep your eyes still.
 Good bitsBad bits
Topical No injection, You can see straight away, Often less bruising/redness. You need to stare into a very bright light, Your eye can still move so if you cannot keep it still during the operation you can make the procedure more challenging, The injection of steroid and anitbiotic at the end of the operation can sting a fair bit, You may see some of our instruments as we operate, Sometimes you can feel some funny sensations from the eye (not pain).
Sub-Tenons Eye is completely still so you don’t have to worry about moving inadvertently, You cannot feel anything because all the nerves are numb, The optic nerve is numb so you cannot see anything. It’s a type of injection (but no needle!), Often there is some bruising redness.

Either technique can give excellent results and your surgeon should be fully versed in both techniques.

I am on Warfarin – can I still have surgery?

Absolutely. Being on Warfarin may mean that you are more likely to have a bit of a black eye after the operation but otherwise it should not affect the procedure itself. We will check your INR either a few days before or on the day of surgery to make sure it is not too high. If it is very high and out of your normal desired range then we may have to post-pone you – there is no point in taking chances when we do not have to. If it is high but you need it high then we can still proceed and do everything we can to minimise the risk of problems.

What does the actual procedure involve?

We start by make an incision in the cornea (the clear window right at the front of the eye). The eye is anaesthetised so you do not feel it. After that we inject some jelly-type substance into the eye to keep it filled up and allow us to see what we’re doing. The cataract is surrounded by a clear flexible shell called a capsule. It can be likened to a smartie with the lens being the chocolate inside and the crispy coating the flexible shell (clear of course). We create a circular opening in the front of this capsule and inject some water to free up the cataract.

We now utilise a probe called a phaco-emulsification probe. This instrument has a needle-like tip, which vibrates at an extremely high rate of speed producing high frequency sound waves.This ultrasonic vibration breaks the cataract into fine pieces, which are suctioned out of the eye through the probe. After all the cataract material is removed we are left with the clear bag. We use this clear bag to support the new synthetic lens we place into the eye. Because we utilise very small incisions and design them to be self sealing we do not usually require a stitch in the eye to seal it. Sometimes though the wound may not be completely water tight and a small stitch is needed to hold it closed until it heals.

Once we are happy that the lens is nicely in position and the wound is sound we inject an antibiotic and steroid combination. This last bit can sting a bit I’m afraid.

I cannot lie flat very easily - can I still have the operation?

Yes you can but it really depends upon how bad the problem is. We need to get you reasonably flat in order to fit you under the operating microscope. Usually the operation only lasts approximately 15 minutes so the great majority of people can manage it. Often we can try you and see how far you can lie down. We should be able to get you comfortable and get around any problem you have.

What can go wrong? What are the risks?

Cataract surgery is one of the most commonly performed types of surgery and it is one of the safest too. Unfortunately no form of surgery is completely risk free and when the risks involve your vision we have to take them very seriously indeed. Modern cataract surgery has advanced dramatically over the years and the odds are very high that you will sail through the procedure. Are you guaranteed a good result – definitely not – there are no guarantees but your ophthalmologist will do everything they can to ensure you are delighted with the result. You need to go into the whole procedure with open eyes however (excuse the pun!).

The most significant risks and complications are:

  • Infection:
    This is sadly one of the worst complications of cataract surgery. Thankfully it is exceedingly rare. Approximately 1 in 3000 to 1 in 5000 patients suffer with this problem. We do everything we possibly can to minimise the risk of this problem and we treat it aggresively if we suspect it is occurring.
  • Retinal Detachment:
    Patients who are very near-sighted are at most risk of this. If you develop this complication you may have to have another operation to repair it.
  • Raised pressure in the eye:
    Sometimes the pressure can go high inside the eye giving you a localised ache. If you are at particular risk of this we can give you medication to prevent it. It is usually self-limiting and will go away without causing any long term difficulties.
  • Dropped lens:
    Rarely when we try and take your cataract out of the front of the eye it falls to the back of the eye either due to a weakness within the capsule of the eye or due to an abnormal adhesion between the lens and the capsule. This would need another operation to take it out.
  • Corneal decompensation:
    The cornea is the clear window through which you see. It is kept clear by the action of the cells lining its inner surface.  These cells die off slowly as we age. By messing around with the eye in the form of surgery we innevitably cause some of those cells to die off. If we tip the eye over the balance and we cause your cornea to lose too many of these cells it can cause the cornea to become cloudy as it fills with fluid.  Unfortunately we cannot predict which patients are going to get this problem. A slightly cloudy cornea on the morning after surgery is not uncommon and usually settles. If the cloudiness does not settle then you may need some other form of surgery to replace the cornea. This is rare.

Do I have to wait until the cataract is ripe?

In a word – no. A cataract is a visually significant lens opacity and so if it is bothering your vision and affecting your quality of life significantly then it is worth removing. Sometimes if the cataract is only very mild we will advise you to leave it alone. In the end however we are there to provide you with all the information and allow you to make a fully informed choice.

Who will do my operation?

A qualified surgeon will undertake your surgery. Your Consultant Ophthalmologist is responsible for your care and he/she will ensure that you are operated upon by someone with the skills and abilities to do the procedure. Sometimes we train surgeons and they will operate under our direct supervision. There are several different grades of surgeon but all are capable and experienced.

Will my vision definitely be better?

I sincerely hope so. We are undetaking this procedure with the specific purpose of making your vision better however sadly there are no guarantees. Things can go wrong and sometimes (thankfully very rarely) you can end off worse after the surgery than before.

What sort of lens do you put into my eye and do I have a choice?

There are several different types of lenses available. They all work in a similar fashion. They are designed to focus incoming light on the retina so you can see clearly. Technology is advancing all the time but currently there are three types of lenses in use:

  • Clear monofocal lenses that have one fixed focus: This type of lens is the most commonly used and focuses all the light for distance onto the retina. Usually we choose a lens which allows you to see in the distance clearly however you will need reading spectacles.
  • Multifocal lenses: These lenses try to focus the light from both near and distant objects onto the retina. This means that theoretically you will be able to see in the distance and also close us without reading spectacles. These lenses will not work in everyone however.
  • "Yellow lenses": These are relatively new lenses which are designed to block out potentially harmful blue light rays. Theoretically these lenses stop damage to the macula (the most important bit for your vision) and prevent age related macular degeneration. The yellow tint to the lens does not affect the natural colour of things or the clarity of your vision.

Not every lens is suitable for every patient. You need to discuss the choice of lens with your surgeon and together you can decide what is best for you.

Will I need spectacles after the operation?

Not everyones eyes are the same size and shape so there is not one power of lens which will be suitable for all. We take several measurements and undertake calculations to work out what strength of lens is appropriate for your individual eye. In most people we aim to leave you so that you do not require spectacles for distance but sadly the calculations are not always spot on. You may need some slight spectacle correction to give you the clearest vision in the distance. Unless you have a multifocal lens you will almost certainly need glasses for reading.

Can I be knocked out/asleep for the operation?

You can but we strongly recommend that you are not. However fit you are a general anaesthetic is not completely risk free. Local anaesthetic is by far the safest and best way to do your cataract surgery. However nervous you are about the whole thing I can guarantee that I/we have operated upon people much more nervous than you without any problems. In the end you are the boss however and if you are adamant that you want a general anaesthetic then we cannot go against that. We can strongly and repeatedly try and talk you out of it however.

What treatment do I need post-operatively?

After the operation you will have a pad and shield on overnight. In the morning you will take off the pad and sheild and then start off the drops. Different surgeons use different regimen however you will probably use a steroid drop and an antibiotic drop usually four to six times a day. My post-operative regimen is Maxidex (a steroid) four times per day for around three to four weeks and Chloramphenicol (an antibiotic) four times per day for the first two weeks. You should wear your shield overnight for the first 2 weeks. This is to stop you waking overnight half-asleep and rubbing the eye.

Can I drive after my surgery?

Not immediately. Different surgeons have different recommendations however legally you are OK to drive as long as you have the required vision (able to read a number plate at 20.5m) and that you are adapted to your new vision. I usually recommend waiting approximately two weeks after your surgery before restarting driving. You must be confident that you can reach the legal requirement for vision and that you are comfortable with the new state of your eyes. If in doubt I suggest you avoid driving until you are seen by your surgeon.

What sort of aftercare do I require?

You should wear your shield overnight for the first 2 weeks. This is to stop you waking overnight half-asleep and rubbing the eye.

Be sensible about lifting heavy things – don’t strain.

Your eye can be a little light sensitive so you can wear normal sunglasses.

Avoid swimming for the first month.

Showering is fine but avoid getting water or soap into the operated eye. Wait about a week before washing your hair and then be very careful.

Avoid bending down in the first few weeks. Bend from the knees not the waist if you can. Again be sensible.

Can cataracts come back?

No, once we remove the cataract it cannot recur. However, the back capsule of the old lens which we use to support the new lens can cloud over months, years or even decades later. It is called Posterior Capsular Opacification, occurs in about one third of patients and is easily remediable by laser treatment.

Can you do both eyes at the same time?

We can but we won't unless there is a very good reason to. If something was wrong with our fluids or equipment (almost unheard of but a theoretical possibility) we would jeopardise both eyes by operating on them at the same sitting. Certain patients who have specific disabilities or definitely require general anaesthetics may be eligible.

I have had cataract surgery and I’m getting problems, what do I do?

  • My eye is red
    Often a blood vessel is ruptured at the time of surgery giving a confluent blood red appearance. This looks dramatic but is of no concern. It will subside gradually probably going yellow before it disappears. Some redness in the form of dilated blood vessels is normal after surgery. It too will gradually abate. If the eye is becoming redder rather than settling or if the eye is still very angry after a week then there may be a problem. It is worth contacting your surgeon or his/her team to ask for advice. If the eye is getting redder and this is associated with pain and reducing vision you need to seek attention immediately.
  • My vision has gone down
    If your vision started off good on the day after your surgery and then deteriorates within the next week then you should contact your surgeon or his/her team for advice. If this reduced vision is associated with redness and pain you need to seek attention immediately.
  • My vision is not as good as I expected it to be
    We do the surgery to improve your vision however sometimes other things such as age related wear and tear at the back of the eye can make the result less perfect than we’d hope.  Sometimes the cornea (the clear window a the front of the eye) can be a little bit cloudy on the first few days after surgery. Your vision should gradually improve. If your vision is not improving or you feel the vision is worse than before the operation then contact your surgeon or his/her team to ask for advice.
  • My eye feels like there is something in there
    This is almost innevitable as you will feel the incision in the cornea. This will pass over time but it may take a couple of weeks.
  • I have run out of my drops
    If you have run out just a few days before you were supposed to then do not worry. Usually this is not a problem. If however you run out of drops more than a week before you were due to then it is probably safer to get some more from your GP.