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Understanding cataracts RCOphth

Understanding cataracts · 2019. 12. 13. · Understanding age-related macular degeneration Understanding Charles Bonnet syndrome ... About cataracts Cataracts are a very common eye

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Page 1: Understanding cataracts · 2019. 12. 13. · Understanding age-related macular degeneration Understanding Charles Bonnet syndrome ... About cataracts Cataracts are a very common eye

Understanding

cataracts

RCOphth

Page 2: Understanding cataracts · 2019. 12. 13. · Understanding age-related macular degeneration Understanding Charles Bonnet syndrome ... About cataracts Cataracts are a very common eye

RNIB’s Understanding seriesThe Understanding series is designed to help you, yourfriends and family understand a little bit more about youreye condition.

Other titles in the series include:Understanding age-related macular degenerationUnderstanding Charles Bonnet syndromeUnderstanding dry eyeUnderstanding eye conditions related to diabetesUnderstanding glaucomaUnderstanding nystagmusUnderstanding posterior vitreous detachmentUnderstanding retinal detachmentUnderstanding retinitis pigmentosa

All these leaflets are available in audio, print and brailleformats. To order please contact RNIB’s Helpline on 0303 123 9999 (all calls charged at local rate), [email protected] or visit rnib.org.uk/shop

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Page 3: Understanding cataracts · 2019. 12. 13. · Understanding age-related macular degeneration Understanding Charles Bonnet syndrome ... About cataracts Cataracts are a very common eye

ContentsAbout cataracts . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

How your eye works . . . . . . . . . . . . . . . . . . . . . . . . 5

Causes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Symptoms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Treatment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Complications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

Other eye conditions. . . . . . . . . . . . . . . . . . . . . . . 18

Coping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Useful contacts . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

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About cataractsCataracts are a very common eye condition. As you getolder the lens inside your eye gradually changes andbecomes less transparent (clear). A lens that has turnedmisty, or cloudy, is said to have a cataract. Over time acataract can get worse, gradually making your visionmistier. A straightforward operation can usually removeyour misty lens and replace it with an artificial lens toenable you to see more clearly again.

This guide is about cataracts in adults. Some childrendevelop cataracts, called congenital cataracts, before orjust after birth but these are usually dealt with in adifferent way to cataracts in adults. You can findinformation about congenital cataracts on our website at rnib.org.uk

cornea

pupil

retina

macula

vitreous

iris

to the brain

optic nerve

lens

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How your eye works When you look at something, light passes through thefront of your eye, and is focused by your cornea and yourlens onto the retina. Your lens is normally clear so thatlight can pass directly through to focus on your retina(the lens is clear because of the way the cells in the lensare arranged). Your lens focuses light onto the retina,which converts the light into electrical signals. A networkof nerves delivers these signals from the different partsof your retina to the optic nerve and then onto yourbrain. Your brain interprets these signals to “see” theworld around you.

Your lens can change shape, allowing you to focus onobjects at different distances, called “accommodation ofvision”. As you get older, your lens is unable to changeshape as well as it used to; even people who can seeclearly in the distance without glasses will need readingglasses to see things up close. This process is not causedby a cataract.

Cataracts result from changes in the way the cells of yourlens are arranged and their water content, which causesthe lens to become cloudy instead of clear. When thishappens, light cannot pass directly through your lens andyou may notice problems with your vision. A cataract isnot a growth or a film growing over your eye; it is simplyyour lens becoming misty.

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CausesCataracts can be caused by a number of things, but byfar the most common reason is growing older. Mostpeople over the age of 65 have some changes in theirlens and most of us will develop a cataract in time. Apartfrom getting older, the other common causes of cataractinclude:

diabetes

trauma

medications, such as steroids

eye surgery for other eye conditions

other eye conditions.

In general, the reason why you have developed a cataractwill not affect the way it is removed.

Most cataracts are caused by natural changes in yourlens, which happen as you get older. However, thefollowing factors may be involved in cataractdevelopment (please note that these are only suggestedcauses which are the subject of ongoing research):

tobacco smoking

lifelong exposure to sunlight

having a poor diet lacking antioxidant vitamins.

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SymptomsCataracts usually develop slowly and although symptomsvary there are some symptoms that most peopleexperience. Most people will eventually develop acataract in both eyes, though one eye may be affectedbefore the other. When your cataract starts to develop,you may feel your sight is not quite right. For example, ifyou wear glasses you may feel that your lenses are dirty,even when they are clean. Gradually, you may find yoursight becomes cloudier and more washed out. Edges ofstairs or steps become more difficult to see and you mayfeel you need a lot more light to read smaller print.

Another common symptom of a cataract is a problemwith bright lights. Lights can seem to glare, or you mayfind that the headlights of a car dazzle you more thanthey used to. You may also notice a slight change in yourcolour vision – things may appear more yellow thanbefore. This often happens if one eye develops a cataractfirst and colours look different when you compare oneeye with the other.

If you notice any of these changes, you should have youreyes examined by an optometrist (optician) who will beable to tell whether you have a cataract or not. Theoptometrist will then discuss how badly the cataract isaffecting your vision and, if you agree, refer you via your

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GP to the eye clinic. You may be told during this eyeexamination that you have early cataract or initial signsof a cataract which does not need referral. If you areunsure about anything during your eye examination thenask to have it explained. Eye examinations are free foreveryone in Scotland and for everyone over sixty yearsold in the UK. Many other people also qualify for freeeye examinations.

If a cataract is not removed, your sight will becomeincreasingly cloudy. Eventually, it will be like trying to seethrough a frosted window or a heavy net curtain or fog.Even if your cataract gets to this stage, it can still beremoved and your sight may be the same or almost thesame as it was before the cataract developed.

TreatmentThe only effective treatment for cataracts is surgery toremove your cloudy lens and replace it with an artificiallens implant. This is done by an ophthalmologist (eyespecialist) at a hospital. Lasers are not used to removecataracts and there is no evidence to suggest thatchanging your diet, taking vitamins or using eye drops

Page 9: Understanding cataracts · 2019. 12. 13. · Understanding age-related macular degeneration Understanding Charles Bonnet syndrome ... About cataracts Cataracts are a very common eye

can cure cataracts. Cataract surgery is available free onthe NHS.

Removing cataracts

The operation to remove your cataracts can be performedat any stage of their development. There is no longer areason to wait until your cataract is “ripe” beforeremoving it. However, because any surgery involves somerisk, it is usually worth waiting until there is some changein your vision before removing the cataract. This issomething to discuss with your optometrist, as a goodtime to have the surgery may vary from person to person.

Most people choose to have their cataracts removedwhen the change in their vision starts to cause themdifficulties in everyday life. The timing of this varies fromperson to person. If you have problems in bright light, oryou find reading or getting out and about, cooking orlooking after yourself increasingly difficult then it may betime to consider having your cataract removed. When yougo to your appointment in the eye clinic you need tomake clear to the specialists any everyday problems youare having.

When you are first referred to the eye clinic you will havean outpatient appointment to examine your eyes and

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then discuss the best options for you. This is the time toask questions and it is useful to write down any you havethought of beforehand.

Many people with cataracts are still legally able to drive.If you have any concerns about whether you should bedriving, your optometrist should be able to tell youwhether your sight is within the legal limits for driving.Sometimes people may be legally able to drive but mightfind driving difficult in bright sunlight or at night. If thisis the case, then you may think it is a good time toconsider having your cataracts removed.

Pre-surgery

Before you have your cataract surgery, your eye healthand general health will be checked carefully in what isoften called a pre-operative assessment. Your vision andyour eye will be measured very carefully. This is usuallydone by a machine which measures the length of youreye ball and the shape of the front of your eye. Thesetests help the ophthalmologist decide which lens toimplant when they perform your operation, to make sureyour vision is as good as possible after the surgery. If youhave had laser surgery to reduce your need for glassesyou need to tell your ophthalmologist as soon as

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possible, as this may affect the power of the lens theyimplant. If you have a cataract in both eyes yourophthalmologist will use these tests to decide whichcataract to remove in the first operation. In most cases,this is the eye with the worst cataract.

Surgery

Cataract surgery usually takes about 30 to 40 minutesand most people go home from hospital a few hourslater. It is usually done with a local anaesthetic, whichmeans you will be awake during the operation but youwill not feel any pain. You can talk to the operating teamif you need any assurance. The local anaesthetic mayinvolve drops and an injection or just drops.

For your surgery, you will be given drops to dilate yourpupil. Your face will be covered by a sheet, which helpsto keep the area around your eye clean during theoperation. The most common way to remove cataracts iscalled phacoemulsification. This technique uses highfrequency sound energy to break up your natural lenswith the cataract. Only really small cuts are used, so youdo not need any stitches, and this helps to speed up yourrecovery from the surgery. Usually, the ophthalmologistuses a machine which acts as a microscope to get thebest view of your eye.

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The lens in your eye is made up of different layers and theoutside layer is called the lens capsule. During theoperation, the ophthalmologist cuts through the front ofthe lens capsule so they can reach the lens inside. Usingthe same instrument, the ophthalmologist can break upyour lens and the cataract inside your eye, and remove itusing suction. Your lens capsule is kept in place so thatthe artificial lens implant can be placed inside it. The tinyimplant is folded so that it can be put into your eyethrough the same instrument that is used to remove yourcataract. Once it reaches the right position, theophthalmologist unfolds the artificial lens so that it sits inthe right place inside your lens capsule.

As you are awake during the operation it is important thatyou keep as still as you can. You will be able to hear whatis happening in the operating room and can communicatewith the ophthalmologist and the nurses. They are on handto reassure you and offer any help if you needto move.Because the eye is anaesthetised and your pupil is dilated,you may be able to see some lights and movement but notthe details of the instruments used. You should not feelany pain in your eye.

A short time after your operation, your eye will beexamined, to make sure the operation has been a success.

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Your eye will be covered with a dressing which stays inplace when you go home, normally a few hours later.Your eye may begin to feel sore once the localanaesthetic starts to wear off. Usually the pain is not toobad and you can take a painkiller tablet, such asparacetamol, to help. The dressing, which is put on in thehospital, usually needs to stay on your eye overnight, butyou should be able to take it off the following morning.Your eye may look red and you might develop somebruises but these will improve over the next few days.

Immediately after the operation

Some people can tell that their sight has improvedstraight away. If your cataract was quite mild you mightnot notice a big change in your vision but if your cataractwas quite bad you may be able to notice a biggerimprovement. Either way, your sight may not be as goodas you expect for the first week after the operation, asthe eye is still recovering from the surgery and willprobably be a little swollen.

Immediately after the surgery you will be given eyedrops. You will probably have two types of drops – an antibiotic drop to prevent infection and a steroid dropto help reduce any swelling. It is important to take these

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drops as the ophthalmologist recommends and tocomplete the course. Your eye clinic should be able togive you information on how to use your eye drops. If youhave problems using the drops you should let your GPknow as they may be able to arrange some help for you.

Most people have no problems after the surgery and theyare up and about as normal the next day. Some peoplemay find certain lighting too bright, wearing sunglassesor tinted lenses can help with this but usually this is onlyfor a few days after the surgery. If your eye is verypainful or your vision suddenly gets a lot worse, then youshould let the hospital know as soon as possible as thismay mean they need to see you again.

Activities

After surgery, you can usually go back to your everydayactivities as soon as you feel able. Apart from taking eyedrops, you can usually carry on as normal but you mayneed to avoid the following for the first week to ten days:

rubbing your eye. You may have to wear an eye shield(patch) when you are sleeping to avoid rubbing youreye

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swimming (until your ophthalmologist says you can) toavoid contact with dirty water while your eye is healing

strenuous exercise, contact sports and heavy lifting.Everyday lifting like light shopping is usually fine, butheavy lifting like moving furniture is best avoided

wearing eye makeup until the hospital are happy withyour recovery.

You also need to take extra care:

when it is windy or dusty outdoors, in case somethingblows into your eye, but you don’t need to stay indoors

with bright lights for a few days after the surgery. Youmay need a pair of sunglasses or tinted lenses to helpyou for a few days

washing your hair. Avoid soapy water in your eye.

Usually, you will see the ophthalmologist about six weeksafter the operation. At this appointment you can askthem about returning to all your usual activities.

When should I have new glasses?

The lens that is implanted in your eye is usually designedto give you clear distance vision without needing glasses.

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Sometimes this is not quite achieved and you will need apair of distance glasses to fine tune the focus and getthe best possible distance vision. Because the lensimplant cannot provide in-focus near vision, nearlyeveryone needs to wear reading glasses after theoperation and usually this is a different pair than you had before the operation.

In most cases an eye examination, sometimes called arefraction, will be done four to six weeks after theoperation. This may be done by an optometrist in thehospital or you may be asked to see your ownoptometrist, in the high street.

Some lens implants are available which try to provideclear vision in the distance and up close. These are calledmulti-focal lenses. There are different types available, butusually implanted in the same way as the more commonlenses. At the moment, multi-focal lenses are normallyonly available privately.

Between operations

If you have cataracts in both eyes, the period betweenhaving the first and second operation can be difficult.This is because your eyes will not be balanced in termsof glasses and correction for any short or long sight you

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may have. Normally, people are encouraged to wait untilthey have a second operation before getting new glasses.This avoids the need to buy glasses that would only beuseful for the short time between the operations. Somepeople find they can manage with their old readingglasses, but this may not be possible for everyone. Thegap between the two operations is usually about sixweeks to three months so most people can manage.

ComplicationsCataract surgery is generally very successful. Only aboutthree per cent of people who have cataracts experiencecomplications. The most common complications can bedealt with and usually do not affect sight in the long term.

One of the most common complications is a thickeningof the lens capsule which holds the lens in place. Thismay occur a couple of months or even years after theoriginal operation. If this happens, your sight will becomecloudy again, as though the cataract has come back.Doctors call this complication posterior capsuleopacification or posterior capsule thickening and it isusually easily dealt with by a small laser operation donethrough an outpatient appointment. There is information

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available on posterior capsule opacification if youcontact our Helpline on 0303 123 9999 or check ourwebsite at rnib.org.uk

More serious complications are much rarer and include:

retinal detachment

problems with the lens implant, the wrong lens implantor problems with its position

a break in the lens capsule

infection.

These complications are much rarer and treatments areavailable which will minimise their effects on your vision.Before being offered a cataract operation theophthalmologist will talk you through the potential risksspecific to your situation.

Other eye conditionsPeople with cataracts often have other eye conditions aswell. This is because many eye conditions affect olderpeople. For example, many people with maculardegeneration, glaucoma or diabetic eye problems also

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develop cataracts. Removing cataracts when you haveother eye conditions is possible, but there may be otherthings to consider. Ask your ophthalmologist to explainany extra considerations for a cataract operation in yourparticular circumstances.

CopingBeing diagnosed with an eye condition can be veryupsetting. You may find that you are worried about thefuture and how you will manage with a change in yourvision. All these feelings are natural. RNIB can help youwith our telephone Helpline on 0303 123 9999 and ouremotional support service.

Most people who have cataracts without any other eyeconditions have very good vision following the operation.However, if you have another eye condition that affectsyour sight, or there are complications with the cataractsurgery which affect your sight, then there are lots ofthings you can do to make the most of the vision youhave. This may mean making things bigger, brighter orusing colour to make things easier to see. Ask yourophthalmologist, optician or GP to refer you to your local low vision service.

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Our Helpline can also give you information about low vision clinics and the support available from socialservices and can also offer advice if you have anydifficulties accessing these services. Our websiternib.org.uk offers lots of practical information aboutadapting to changes in your vision and products thatmake everyday tasks easier.

Useful contactsRoyal National Institute of Blind People105 Judd Street, London WC1H 9NE0303 123 [email protected]

Royal College of Ophthalmologists17 Cornwall Terrace, London NW1 4QW020 7935 0702www.rcophth.ac.uk

Driver and Vehicle Licensing Agency (DVLA)Drivers Customer Services (DCS)Correspondence Team DVLASwansea SA6 7JL0300 790 6801www.dvla.gov.uk

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We value your feedbackPlease help us improve the information we supply bysharing your comments on this publication.

Please complete the form and return to:FREEPOST RSCB-GJHJ-HLXGRNIB Publishing105 Judd StreetLondon WC1H 9NE(There is no need to use a stamp.)

Alternatively, you can email [email protected]

1. Where did you receive your copy of this leaflet?

2. Did you find that the information was presented in away that was easy to read and easy to understand?Please give details of anything you feel could beimproved.

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3. Is there any information you would have foundhelpful, or were expecting to find, that was missing?

4. Further comments. Please use the space below for anyother comments you have on the information in thisleaflet or any aspect of your contact with RNIB.

10004/01/13

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Information sourcesWe do all we can to ensure that the information we supplyis accurate, up to date and in line with the latest researchand expertise.

The information used in RNIB’s Understanding series ofleaflets uses:Royal College of Ophthalmologists guidelines fortreatmentclinical research and studies obtained through literaturereviewsinformation published by specific support groups forindividual conditionsinformation from text booksinformation from RNIB publications and research.

For a full list of references and information sources used inthe compilation of this leaflet email [email protected]

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This leaflet has been produced jointly by the RoyalCollege of Ophthalmologists and Royal NationalInstitute of Blind People, with sponsorship from Alcon Laboratories (UK) Ltd (Alcon Eye Care (UK) Ltd).

RNIB and the Royal College of Ophthalmologists havefull editorial control over the content of this leaflet.

© RNIB and RCOphth RNIB reg charity no. 226227RCOphth reg charity no. 299872

Printed January 2013. Review date January 2014.

ISBN: 978 1 85878 711 4 PR10004

If you, or someone you know,is living with sight loss, we’rehere to help.

RNIB Helpline

[email protected]

0303 123 9999