Cataract surgery webinar transcript
Mr Wallace Poon
Good evening, everyone. Welcome and thank you for attending the Benenden webinar tonight I am Wallace Poon, Consultant Eye Surgeon. I’m going to talk about cataract and how we can help you.
A quick introduction about myself, I graduated from King's College Hospital for my medical training, then I did my specialty training at the London and South-East region, and I did a victory retinal fellowship in St Thomas's Hospital, London and I was employed as a Consultant Retinal Surgeon at East Kent Hospitals University Foundation Trust. I specialize at eye trauma retinal detachment, complicated cataract surgeries and cataract surgery complications. Over the years I've done over 12,000 cataract operations and last year I've done over 1,000 cataract surgeries. I’m also an honorary lecturer at the University of Kent, supervising postgraduate students on retinal research and I’m also an UK examiner for the European Board of Ophthalmologists.
Now my dad recently had cataract surgery and we discussed a list of questions; I think it'll be really useful to share this with you. So, this session will cover: what is a cataract? What types of cataracts are there? What causes cataracts? Do I have cataracts? and do I need surgery? What happens in the cataract clinic? What happens before, during and what do I expect after cataract surgery? and what can go wrong with the operation? and where should I go? and which surgeon should be doing my operation?
So, what is a cataract? On the slide you can see two diagrams the right, which I think you can see my cursor here, is the frontal view of the eye. The left here is the cross section of the eyeball, what that means is you cut into half. This is the front part of the eye. This is the back of the eye and the iris which determines the colour of the eye. You can see the pupil right in the middle.
The lens that sits behind the pupil and the retina itself and the optic nerve which takes all the information to the brain.
The eyes as I said works like a camera, the light travels into the eye through the pupil, focused by the lens to the back of the eye - the retina which is also like the film of the camera. The optic nerve then collects all the information sending to the brain. That's what the camera does. What is scatter cataract means the lens losses transparency, the left diagram shows a very sharp image of the eagle you can see here.
With the cataract in the right side of the diagram, the image is compromised. So, what types of cataracts are there? The commonest type is nuclear sclerosis. As you can see in the diagram here, the yellowish colour in the lens which progressively gets denser in the centre, this is more common with the age-related aging changes of the lens.
This is cortical lens opacity, as you can see there there's white spokes on the superficial part of the cataract. This is posterior subcapsular cataract, if I can convince you, you have got the opacity here at the back of the lens. My cursor doesn't work very well. Yes, here we are now you can see the opacity here and corresponds to at the back of the lens here. This is more obvious you can see a dense opacity right at the centre of the back of the lens, this is called posterior polar cataract.
So, what are the communist causes of cataract? The most common is age-related. However, some patients are born with the congenital type which the post polar cataract is one of them. If you get hit very badly with a blunt trauma, you can also suffer from cataract as a result. It's also related to systemic disease, for example if you have diabetes and it can be drug related as well with patients taking steroids either tablets or topical eye drops.
So, do I have cataracts then? Now there are certain symptoms which are common with cataract, for example here the colour becomes faded, things become blurry especially when they're driving at night. Oncoming traffic light causes a lot of glare, or you keep going to the optician thinking the glass is not right or I need stronger and stronger glasses, that's because the cataract is progressing and making you more short-sighted or the patient can have simply ghost vision or double vision and seeing multiple images because of the cataract causing the diffraction when the light entering the eye. So, do I have cataracts then? I think the best thing you do if you have the mentioned symptoms is go to an Optometrist and they will refer you to the Ophthalmologist for further investigations.
Do I need cataract surgery? Well there are clinical reasons which will benefit from cataract operations and is definitely advisable for example the cataract is getting so bad it increase the risk of having a certain type of glaucoma or you're having cataract or you're having surgery on the retina and it will be worthwhile to actually have the cataract done at the same time, or if you're diabetic and because of the diabetes you should have your regular fundal check-up or screening by the local diabetic screening service and they were unable to get a good quality picture. So, yes for those situations it would be advisable to have the cataract operation. Otherwise, only have it done if it's affecting your daily life. So, what do you mean by that? For example, you're not able to see well enough to cope to do your shopping, you are unable now to drive legally or you think it's unsafe and you keep changing your glasses or it stops you from doing your hobbies, you can't play sports anymore, you can't see the golf ball going miles away or in fact you’re painting now.
Talking about painting, there's a story of a very famous painter Claude Monet, a French impressionist, died in 1926. He was diagnosed in 1912, however 100 years ago the technology is not as advanced and there's 50/50 percent chance if you do a cataract operation. You can lose your sight, so he really, really concerned and waited for over 11 years before he had surgery. Now during this period of time he starts describing his garden as more yellowish and more murky and very red and dull and the blue colour becomes darker and very indistinct and you can actually see from his paintings of 1819 of the Japanese foot bridge, you can see the water lily there very beautiful vivid colour but when go to the year 1922, everything is very blurry and there's heavy use of the red tone because he can't distinguish blue anymore. So, should he have cataract surgery? I think he should have it sooner rather than later at Benenden.
Now, what happens in the cataract clinic once you get referred? Now Benenden has a very streamlined dedicated cataract pathway which, first of all, you will see the nurses, you have your detailed medical and social history taken, blood pressure, check your visual acuity, check your intro of the pressure and also we'll do all the investigation necessary, so when you see the consultant he will have everything in front of him to make decision and share the time with you to examine you to discuss the investigation results, he will discuss with you the type of local anaesthetics you will need and decision on the surgery and the risk of operation. Most importantly, he will talk to you about the type of lens implants and what the refractive outcome going to be. You'll get the consent for the surgery and also here at Benenden after the operation you will have 24 hours post-surgery hotline, which if you got any concern, you could always call us.
Now the types of lens implants and reflective outcome is quite a difficult concept to understand because with my own experience at talking to my dad. Roughly, you can think about two type of lenses, one is called the monotonal lenses, what that means is mono is one so it's one point of focus and is either good for distance vision, which is for your driving, watching television or it's only good for near vision, that means when you're doing your reading or you're doing your sewing but not good for both, that means you will still need glasses. Now you might have heard about the concept called astigmatism, which means the surface of the cornea ideally should be like a football nice and round, but a lot of people were born more like rugby balls so it's more curved in one side than the other. This will not be corrected with the monotonal lenses, you will need glasses for both distance and near. This procedure is done by most Ophthalmologists, special lenses is different why it is different is the multifocal lenses is a bit like if you wear varifocal glasses, it internalizes it. That will be able to provide good distance, intermediate and near functional vision. Worked out the use of corrective lenses, which means glasses however special lenses can have problem with glare and reduce contrast sensitivity.
The special lenses will also be able to correct astigmatism and at Benenden here it is only performed by the Ophthalmologist specialized in refractive surgery, which will be the correct people to look after you. Now you can see from the left-hand side of the diagram for the monofocal lenses is nice and clear, but you need glasses for either distance or nearby. On the right-hand side diagram, you can see the concentric rings in the centre, and this is the magic part which allows you to see distance and or near to a certain extent, which will make you more likely to enjoy life without the glasses you're wearing.
Now on the day of surgery, what's going to happen? Once we decide that we're having the operation done, you'll come in and you'll have your pupil dilated, the nurse will check your blood pressure, check your glucose and give you sedation if you need it. Now I would advise to wear comfortable dark-coloured clothing, don't drink alcohol on the day of surgery, I think you might want to numb yourself and separate yourself but don't. Have a light meal or breakfast if you come in the morning.
During the surgery, you'll be sitting in a comfortable operating chair, the chair will automatically lean backwards and will position your head until you are comfortable. We will then put local and static drops and aldine drops to clean the area and then we will drape it, that means a plastic piece of material to keep the operating area clean, now that might be slightly claustrophobic, but we'll be able to lift it away from the face. I will insert a speculum which is a device to keep your eyes open, you'll notice a bit of pressure around the eye, but it should not be painful. Then I will ask you to stare at the operating light, which has got the three bright dots in the middle, you'll have both eyes open blink normally. There will be background music playing, important no singing no dancing, leave that with the nurses. Now the surgery takes around 10 to 15 minutes. Okay we go for a few things, we make a very small incision in the cornea, we peel off the superficial part of the capsule and then you hear some funny noises, that is the ultrasonic needle breaking the cataract into pieces, clearing it out and we will do what we call irrigation aspiration just to clear the rest of the capsule, the back and then we can put a lens implant inside. Once we've done that, we're going to put intra-camera antibiotics, that means a fancy name for putting the antibiotics inside the eyeball, then we'll seal the wound and then we'll be covered with a transparent shield so we can still see through but things will be blurry and this is really important to remind you, you have an operation and don't rub your eye. these are some of the diagrams of the cataract surgery as I mentioned here capsulorhexis is peeling off the very superficial part of the capsule which the cataract sits and that's how we get into it using an ultrasonic needle to break it, once it's all clear we put the lens implant inside the eye.
So, what should expect after surgery? Now you are having an operation so it will be a slight discomfort and might be a bit of pain but should be managed with simple painkillers. If you have severe pain or something you think is not right, do not hesitate to call. You'll be given the eye drops to prevent infection and to control the swelling in the eye, several hours after the surgery the local settings wears off and you can start to feel your eye properly again. Now as I mentioned earlier like this gentleman, he has got a transparent plastic shield to cover the eye, really important don't take it off the first night because you want to make sure you will not rub your eye because that will introduce infection. The whole healing process takes around four to six weeks, you will get better every day, however any surgical intervention things can go wrong during the operation. Around one in a hundred cases when we do the surgery, I can see here the capsule which is holding the cataract can split.
That might take a bit longer to finish the surgery so rather than 15 minutes it might take half an hour. One in a hundred cases rather than just splitting the capsule part, the cataract can drop to the back of the eye, in those cases you need further operation to complete the surgery. Postoperatively the most devastating complication is what we call endophamitis, it happened very rarely one in 1200 cases, it happened because when we do the surgery we have to cut the eye open, so there's a chance that bacteria can get inside the eye during the surgery, but most commonly this actually happens following the operation when the patient thinks I’m all right they start rubbing the eye, getting dirty water into the eye before the wound is sealed and they cause infection. If that happens, we can still treat it, but the outcome might not be as favourable and very rarely one in ten thousand patients can go blind, mostly because of the infection when we perform the surgery. Also, there's a chance you can have swelling in the eye. Systemic oedema is a specific term describing the swelling at the back of the retina, it happens around one to two, three percent and the eye drops normally will set away the surface of the either cornea can also be swollen around 100 cases and again it will settle with time, in most cases after the cataract operation five to ten percent of patients the capsule can become vacant that will cause blurriness again, a bit like oh my cataract is coming back but it's actually not the cataract coming back but the capsular become to thicken that can be easily dealt with what we call YAG capsule automate, it will be a machine you sit there five minutes you walk out you see better by the evening.
So, the next question is where should I go and who should be doing my cataract operation? Now at Benenden we've got a dedicated eye department in a brand new 53 million facility, there's plenty of parking space for you which is free. I know this doesn't sound like important but it's actually really important, you want to be in a tranquil environment rather than driving around trying to get a parking space when you stress out to have the operation done. At Benenden we got the latest investigative tools and the surgical equipment and a team of 12 experienced eye consultants, not to mention that we have got dedicated reflective orthotic surgeons if you want to decide to have your special lenses done. Now why is important at Benenden is I personally I stopped doing my practice anywhere else, now this is because the Lead Clinician, the Matron and the Senior Management Team will work together very hard and create a special dedicated cataract pathway which is streamlined for your convenience. So you come here once listed for surgery and the next time you're coming for the operation rather than attending Benenden multiple times, which unfortunately with some other hospitals this is what's going to happen and also we got dedicated ophthalmic nurses and administrative team to look after you and also the 24 hours hotline post-operatively which you will know you'll be looked after.
So, the message you take home with is if you notice any of the symptoms of cataract, see your optometrist or you can speak to our team. You can get fast access to our 12 experienced eye consultants, if you want to special lenses please mention to the team when you ring them up, as I said we've got a streamlined service and most importantly you've got a 24-hour hotline following surgery and we've got consultants cross-covering each other so even if one of us is on holiday who did your operation you'll be always well looked after and importantly ask your Optometrist for a copy of your referral letter.
Thank you everyone for listening. I think I’m going to hand this over to Jane now.
Thank you Mr Poon, so I have got some questions I’m going to ask you so prepare yourself. Okay so your first question, what is the criteria for cataract surgery people talk about ripeness and size, could this please be explained?
Mr Wallace Poon
As I mentioned in the lecture, when do you need operation for example you don't have other clinical indications you have it done when you think it's bothering you, if it's affecting your daily life so have it done I have got patients which got quite advanced cataract but he said no I don't go out much I just want to sit there, I’m not bothered and then don't have your operation, but if you're an active person, you play a lot of sports, you want to see clearly what you're doing, you're driving at night, you can't tolerate the glare that is good enough indication for you to have your surgery. So, you do not need to wait for it to be right it's right when you think it's necessary it's really your choice.
Okay so next question, I’m 62 and I have glaucoma for which I take two different eye drops, how does this affect my cataract operation?
Mr Wallace Poon
With glaucoma you do have a slightly high risk of having cataract surgeries, depends on the type of glaucoma you had as well, it will not stop you from having cataract operation, as a matter of fact if you have your cataract removed your intraocular pressure will normally drop one or two millimetre mercury, so it's actually advisable however we will need to know how advanced your glaucoma is because if you've got very advanced glaucoma and there's a lot of damage to the optic nerve having cataract operations sometimes can worsen your symptoms, so really depends on how bad your glaucoma is, what type of glaucoma you have but certainly if you got glaucoma you cannot have special lenses and I think we will recommend monofocal lenses for you.
Okay so the next question, I need to have cataract surgery, but I've been putting it off for some time as I’m so worried about having it done while I’m awake, can the procedure be done under general anaesthetic?
Mr Wallace Poon
To be honest though nowadays with cataract operation it is such a mature and well-planned procedure now 99 percent of the operation are done under local anaesthetics and the majority is only happy with eye drops, some patients we will if they're very nervous they cannot keep their eye open. We'll give them a local anaesthetic to numb the eye normally, there's enough there are certain patients we will do it under general anaesthetics number one if you're very worried, you think you cannot keep still, yes by all means have you done under general settings or with the patient's got Parkinson’s, got head trauma and can't keep still, they need general aesthetics, however at Benenden Hospital we do not provide general anaesthetic service so only local anaesthetics at Benenden. If you do think yourself will need general anaesthetics, it will be worthwhile for your Optician to refer you to further to facilities like the NHS which they do a general anaesthetic.
Thank you, okay I have a retinal vein occlusion in my right eye, am I still able to have the operation on both eyes?
Mr Wallace Poon
The answer is yes because patients have residual vein occlusion can still have very good outcome, now that will again depend on the severity of your vein occlusion. I have got patients with vein occlusion which the vein occlusion caused swelling at the back of the eye and they're having active injection, I think you might have it about this intravenous intravitreal injections which stem down the swelling, when the cataract got worse we do the cataract and with the same time they still carrying on with the intravitreal injection to control their swelling and they've got a fantastic outcome. Now without knowing how bad your vein occlusion is, it's very difficult to tell but generally speaking vein occlusion does not stop you from having cataract operation if anything the cataract surgery should be able to maximize what you're able to see with that eye.
Okay so the next person would like to know, I would like to have special corrective lenses during my cataract surgery, would I feel these lenses like I feel contact lenses?
Mr Wallace Poon
No you will not feel it because rather than the contact lenses it sits on the surface of the cornea so every time you blink or you get a grain of sand you will feel the discomfort, intraocular lens implant is inside the eye you do not feel it the most important thing is you do not need to renew it either, once it's inside the eye you stay there forever.
Okay and this is the final question I think, so hi I’m thinking of booking an appointment, I am nervous about surgery and the risks that you mention, what is the success rate of cataract surgery at the hospital?
Mr Wallace Poon
Generally speaking with cataract operation they are very well monitored because all the surgeons have to submit their complication rate to the Royal College of Ophthalmology, at Benenden we have got the electronic patient record I think this is the only one in the country which hasn't got which has got the electronic patient record, they will automatically collect the information and send it through directly to the Royal Colleges for comparison. Now I mean I’m the clinical lead there the success rate or our complication rate which is recognized by the role quality Ophthalmology is one percent I think all my colleagues complication rate is definitely less than one percent for posterior capsular rupture which is one of the benchmark I mean myself my the last one I had was 250 cataracts ago so that is what we look at and my complication rate is around 0.05 percent.
We have got a couple more questions, so what happens if the surgery doesn't work very effectively?
Mr Wallace Poon
Now that will depends on what cause it not working effectively with cataract operation statistically not just at Benenden and any cataract surgery 99 people will see better, with that one percent doesn't see better either there is coexisting pathology, for example the patient already got glaucoma or degeneration no matter what we do with the cataract, their vision will not improve that much or the patients suffer from a complication. If there's a complication, the outcome might not be as good but think about the bright side not a lot of operation can guarantee 99 percent improvement so majority of patients will see better with the cataract operation.
Okay and I have got another question here, so I know I have cataracts growing but they are only affecting my vision very slightly, I’m 70 and I don't want to wait until I’m much older to have this surgery done with multifocal lenses, would you still be able to do the operation?
Mr Wallace Poon
Yes we'll be able to but I think this is the most important thing is the patient need to understand the risk and benefit, okay when you come to see the consultant we'll go through the likely complications again so you can actually decide on yourself the risk and benefit, this is most important from the patient's point of view you know what you're getting yourself into, but what we're saying is you've got 90 percent chance you are going to see better. Now special lens is different category because the consultant needs to choose with you what type of lenses best suited your needs and I think it's that interaction is most valuable to making sure you will get the best out of the question. Operation you don't need to wait until you're well, the oldest patient I've operated on is 102, you do not need to wait that long you have the operation done when you think you need it.
Lovely, thank you. Well, I think that is all the questions, I’m sorry if there are any questions that we didn't answer, but if you provided your name we will do so after the event. So if you would like to book your consultation, please contact the number on the screen before 8pm tonight or contact us between 8 to 6 Monday to Friday, we are offering attendees 50 off an initial appointment with the terms on the screen, you'll receive a short survey and I'd be grateful if you could spare a few minutes to let me have your feedback on today's webinar. Our next webinar is on the 2nd of August with Consultant Orthopaedic Surgeons, Mr William Dunnett and Mr Matthew Oliver discussing hip and knee replacement surgery. So, on behalf of Mr Poon, myself and the team at Benenden Hospital, I'd like to thank you very much for joining us today and we look forward to you joining us again for another webinar very soon. Thank you very much, thanks.