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my name is Oh, let me say hello, everybody. Welcome to this lecture. My name is Kate Host Romana Cherry. I'm a consultant, ophthalmic and vitreoretinal surgeon. So I'm a eye surgeon, and my subspecialty is retinas, which is the back of the eye. So I do, General, uh, eye surgery as well as retinal surgery, which is quite specialized. You you You can't do the tree retinal surgery in the UK unless you've been trained in it. So this lecture is about cataract surgery, and you'll see that the lecture it's two or four. I did prepare four lectures last six months for, uh, for Crisis Rescue Foundation. And they told me that I could do the same lectures again. The first lecture was very basic, and it was about basic anatomy of the eye. And I found that most people knew everything I was talking about. So I've gone on to the second, uh, lecture. So if there is any issues about the basic science understanding of things, please let me know, and I can go back to it. So, um, so this is the second lecture of the four. The other ones were in vitreoretinal third and your ophthalmology. Okay, so we just go through the clinical signs and symptoms of cataracts and show you the different types of cataracts that there are, uh, the preoperative preparation of cataract patient. What measurements we need, what things we do before we actually do the cataract surgery. Then I'll go you to go through some slide shows of, uh, the cataract operation And what bits or what? And then we go through some of the options in the in the terms of intraocular lens implants that are available nowadays. So, uh, so that patient's can make informed. This is quite quite specialized stuff. So it's not much of this that you need to know for medical school exams, but it's actually nice to have the knowledge. I would have really loved to have this knowledge when I was coming through medical school. But at our medical school, we had one week of ophthalmology and that was it. So we didn't really know very much. So So the first one about some clinical signs and symptoms of cataracts. So cataracts, the main tracks, early cataracts. I'm talking about because, uh, in the in the Europe and, uh, in the UK in particular, We're doing cataract surgery earlier and earlier. So the main reason why we do cataract surgery in the UK is now because of glare from oncoming headlights or a rapid change in prescription, where patient's have to change there their glasses every few months, and so it becomes quite expensive. And they want to then have cataract surgery to stabilize that, uh, the rapid engine prescription either could be due to an increased stigmatism, and, um, and we'll go through the different types of a stigmatism there are, or a myopic shift because of the because of the nature of the lens itself, changing and bending the light at different rates. And then finally, you end up with constant dizziness or blurring of vision. This constant fuzziness is not intermittent. As the name says, it's constant. So if somebody comes to you, says my vision is all is pretty bad. But if I blink a few times, the vision clears, then that's usually not a cataract. It's something else, Uh, in particular. It's the here film can that can cause that sort of intermittent blurring of the vision. We'll go through that later, and finally you can get monocular double vision. That means that if you close the affected I you don't see double vision. But if you close the non affected I you see double. So it's monocular because it's not with the two eyes open double vision. So you see two. And that's because any opacity in the media of the eye, whether it's the cornea, the lens or the vitreous, can cause a split in the race entering the eye and give rise to a ghosting effect which patient's can destroy describe as double vision. Um, so these symptoms have you come across them are not due to cataracts. Okay, so if a patient says that strain straight lines are appearing crooked or they've got bends in them, then that's a retinal problem. Almost certainly, it's not a cataract problem. Uh, of course, any problem in the I usually leads to blurring of the vision, so any retinal problem can blur the vision. But if they have additional distortion, then it's not just the cataract, so they could have cataract on top of the retinal problem. But it's not just the cataract, so things to watch out for distortion. Uh, and I can go through the causes of distortion at the later time been ocular double vision. So if they close each eye in turn and the double vision goes, but when they were open both eyes together they see double. Then that's been ocular double vision, and that is not due to cat tracks. That's due to a, uh, imbalance in the extraocular muscles of the eye that moved the eyeballs so it could be a neurological problem. Or it could be due to the the muscles that move the eyeball. So you look in, you need to look into that if they have been ocular double vision, uh, intermittent blurring of vision. So if your vision, as I said, is not a constant blurring, if it's intermittent, then they may have other problems and often in eyes, unlike everything else, you could have more and one diagnosis so you could have cataract with associated retinol problem or we're tearful Problem or you can have all three problems. So just because you have one diagnosis doesn't mean you can ignore the other diagnosis that might be there. So intermittent blurring of vision if their vision is blurred sometimes, but they blink a few times and the vision improves. That's almost certainly due to there, uh, tear film or what we call I surface disease, which includes black writers, whether it's anterior or posterior, Um, and we always use a slit lamp and the the pick of slit lamp again, I don't know how much you you have seen these things. That's a slit lamp that we use always to examine the eyes of patient's and the slit lamp looks at the front of the eye. It looks into the anterior chamber, the iris, which is the colored part of the eye, the lens of the eye and it goes into the anterior one third of the vitreous. But it can't really that instrument alone cannot see the retina. Therefore, we have this tiny little lens down the bottom. You can see it. It's a In this case, it's a 90 doctor lens that we use in order to visualize the back of the eye. So we hold that to the beam of light coming from the slit lamp, and that gives a image of the, uh, retina that we can see. So there's a picture of a slit shining onto the eye and the first place where it hits. Um, I wish. Oh, yeah, I have a pointer. I can. So the front of this is the front of the cornea or the epithelium. As you know, the cornea has got five layers, the most superficial layer being the epithelium of the cornea. So that layer looks at the epithelio. Underneath that is the Stroma. There's Bowman's layer and SMEs layer, which you can't see because they're too thin. So they all are seen as the stroma, and then inside, if you can see, my arrow is the endothelium, which is the single cell layer whose function is to keep your cornea is clear. It has a sodium potassium pump that pumps away irons and therefore keeps the cornea clear, and therefore you can see through it. If that the endothelium gives up functioning, then your your cornea becomes completely waterlogged than a Pake, and he won't see anything. And that happens sometimes if the cataract surgery has been very traumatic. So we always have to try to put as little power as able to save as many cells of the endothelium as possible, because we know that we're born with center certain number of cells per square millimeter of endothelial cells. And what we're born with is what we're going to have for the last of our life. So, like nerves, they don't regenerate. And as we get older, we all lose our endothelium a little bit. And things like cataracts, surgery or at any other surgery or trauma can reduce the number of endothelium beyond the basic level where they can keep the cornea clear. And so, therefore, some of the times if you are not careful and doing cataract surgery, you can traumatize the cornea and cause corneal opacities because of the reduced number of endothelial cells. Uh, so that's called corneal decompensation. And then you're into the realms of graphs, corneal graphs. If this doesn't clear, okay, so the next bit of the slit that is there is shining on the brown bit of the iris brown bit of the eye that's called the iris. So between the endothelium and the irises, the anterior chamber, that's what we look for cells, inflammatory cells to see if people have got anterior, you be itis uh, with the slit cells or flare. You might have heard that flare is protein released from the eyes. Cells are inflam inflammatory, um, neutrophils that are in the anterior chamber. When the eyes inflamed. Then, uh, this the front bit of, uh, the lenses, the next layer that the slit is hitting so you can see that's anterior capsule then inside it is the actual nucleus of the lens with the cortex and the nucleus of the lens, and you can see this clear cataract that's forming This type of cataract is called a nuclear sclero to sclerotic cataracts. So nuclear scoliosis is the name of the cataract, and then that's the posterior capsule. And as you can see, you can't see very much into the vitreous because it's relatively clear, so you can only see the anterior one third of the vitreous with the slit lamp. So go on. So this type of play track is a cortical Patrick. It looks like the spokes of a bicycle who went to the next one without me wanting to go that causes mainly glare. Vision isn't usually affected very much. It might drop to 69 or something like that, but it doesn't really affect the vision too much, but they get a lot of glare, so that they can't really look into bright lights or oncoming headlights from other cars coming on at nighttime, when the pupils dilated is really so bad that they stopped driving at night. So those are the questions you need to ask when you're looking for early symptoms from cataracts, you start of Catholic, So this one now is the cataract. If you can see that's the front of the lens. That's the reflects Zhishan of the slit lamp from the anterior part of the capsule. Then there's the cortex, and then this bright light is reflecting off the posterior capsule or back of the lens. And so this is called the posterior subcapsular. Cataract and this type of cat track are usually second trauma or, uh, steroid used, but they can be due to other causes such as idiopathic. They can just come on without a apparent cause. They do tend to affect vision very quickly and cause a shift in short sightedness. Um, and they can within a few months. Patient's can lose their vision from this, so you may think that something else is going on. But it's actually the cataract that's getting worse and affecting the central vision. So that's called the posterior subcapsular cataract. Okay, so and then there is a whole load of other cataracts, so this is probably a congenital cataract. Uh, sometimes there's Christmas lights. When you shine the light, you can see different reflex from the different proteins inside the lens, and that's called a Christmas tree. Cataract, this is supposed to be. I couldn't get a picture of the proper Christmas tree cataract, but this is the closest to it. So there's all sorts of winter mother fel stuff, and this is a total cataract. Basically, the cataract has got so dense that it's become white and using your 90 doctor lens and the slit lamp, you're unable to look at the back of the eye. Or, if you want, using your direct of time a scope, you won't be able to see the retina at all. In these cases, we have to warn patient's that there could be other pathology on the retina, that we do their cataract and because we can't see the retina, we don't know what the vision would be like. We can do ultrasound scan of the eye if they've got a total cataract and no view, too. Yeah, and the ultrasound can pick out gross pathologies such as a total retinal detachment or vitreous hemorrhage. But it doesn't pick out small problems. You know smaller problems such as epiretinal membranes or small rhythm with attachments or retinal detachment with shallow subretinal fluid. So you even if you do an ultrasound, you still have to give a guarded prognosis to patient's about their vision, saying that because we can't see the retina, we can't tell you for sure that your vision is going to improve. If the if the retina is intact and working properly, then your vision will be back to normal. If it doesn't, then it won't and we have to investigate further. So these are the monofocal intraocular lens implant. As you can see, the implant has two parts. Uh, this is the optic of the implant, this round bit, and that's what the focusing is done through. So if you can see this fine circle at the front, that's the, uh, anterior capsulorrhexis that's done. So you remove the anterior capsule of the lens in a circular fashion. You scoop out the cataract, break it, break it up with the ultrasound called phacoemulsifier vacation. Then you have a folded implant. These days, most implants are folded up in a tube and you inject it into the bag and it unrolls like a carpet inside the eye. And, uh, this has this is the shape of it. So behind this lens, what supporting the lenses? The posterior capsule, which is fully in fact Oh, come back. Uh, and Abdul is health the eyeball with structure called Azzoni ALS which can't see this is behind the iris. Okay, so we've talked about this, that you can have multiple pathologies which give rise to, uh their symptoms and cataracts being only one of the pathologies. And these are some of the other common concurrent pathologies I surface disease or um, or, uh, dry eyes is quite common. About 20% of people over the age of 70 have got it, and it gets worse when the central heating, when winter comes and the central heating is come on because that produces dry heat. And often the patient's become much more symptomatic in winter. And when spring and summer come, they seem to be better because the dry heat stops and the heating goes off and people tend to get better. Also, if you wear glasses, your eye surface disease is better because the glasses ask act as a shield. Stop evaporation of your own natural tear filled, Uh, and if you lift the glasses, you might get dry eyes even more so that's probably why some of the times after cataract surgery I surface disease becomes worse. Uh, because first, the incision that you make to do cataract surgery can affect the the the distribution of the tear film and secondly, uh, so that can last about six months. But eventually that part goes back to normal. But the second thing is a lot of people come out of glasses once they have their cataracts done. And that part, where the glasses stops the evaporation of the tear film, acting almost like a lid in front of the eye that's removed. So then they get predisposed to getting dry eye symptoms more frequently. Uh, epiretinal membranes. This is scar tissue on the retina. That and scar tissue by nature contracts so it can contract on the retina and cause wrinkling of the retina. And that's where people see instead of straight lines, distorted lines. Um, but that's a lecturer in itself will talk about that in the Vitreoretinal lecture and then the other common thing in this age group of 70 plus, where most people have their cataracts. Tan is age related macular degeneration. That's where abnormal blood vessels start to glow from underneath the court. The choroid under the retina onto the underneath the retinal pigment, epithelium or the retina itself and can affect vision and again discusses sudden distortion. And there's two types of this. The wet type and then the dry type is just the degeneration of the photo receptors that becomes more and more frequent as time goes on, leading to geographic geographic atrophy. Right? So the operative preparation of patient that's the second part. Um, so the thing that we do always before we can do cataract surgery is doing the measurements of the curvature of the cornea and the the length of, uh, eyeball the, uh, the diameter of the eyeball from the front to the back. Because based on these two measurements, we can predict through certain formula what power of an implant we need in order for the patient to see distance clearly or close up clearly So, uh, the measurements of the, uh, corneal, uh, curvature in two in perpendicular directions to per particular directions and the length of your eye length of patient's I using ultrasound are the two very important measurements that we make. There are other, uh, less important measurements such as anterior depth, uh, anti your chamber death size and the thickness of the cataract. But these are not as important. The main things that go in the formula are the axial length and the curvature of the cornea. Sometimes some formula take into account the axial depth axle, uh, anterior chamber depth. But most formulas don't have that. So this is what, uh, As you can see, there's all sorts of things to make sure that your biometry is as accurate as possible. As you can see on the right hand, there is a tick on the corneal reflexes, but on the left, there's no tick. Um, here it's, uh, exclamation mark of care, because probably this patient suffers with dry eyes, and therefore the reflexes can get. Really, the measurements can get really affected by that. So one of the things you can advise patient's is to do lid hygiene and use lots of artificial tears before they come in for their measurements. And that tends to reduce their errors that we have in measuring patient size. Um and yep, so we'll just go to the next slide. So this is the printout that we get when we go to do the cataract surgery. Once we have done the dye Mitory as the the Biometry. As you can see, there's the A L. It stands for axial length, so the actual length in the right eye of this patient is 24.17 millimeters, and there's the standard air for it. The Keratometry shows that they're 44.353 doctors in one direction and 90 degrees to it. They have a 44.6 doctor, so most corneas have got some a stigmatism, but usually they're less than one doctor, which means they're not significant. So, as you can see, this patient has minus 0.53 up. There's a stigmatism, 100 and 23 degrees. I need to go through the original language if you don't understand what these figures mean. So at the end, you can tell me if that would be beneficial or not. But that's another lecture in itself. So as you can see, there's different formula here. So the S R K T is the one that we I tend to use or most people tend to use. Then there's other formulas, such as haggis. Uh huh for Q Holiday And it used to be that they were okay for certain, um, for certain actual actual length. Some formulas were more accurate than others. But most people in the UK now use the S R k T, and there's a progression on that as well. So as you can see on this, if I put an 18 doctor, uh, lens of a constant 1 19, then I get almost 00. Outcome 00 means they can see distance clearly and then all if they go from monofocal lens, all they have to do then is put a pair of reading glasses or plus 2.5 sor threes in order to see close up. I hope that all makes sense to you, and it's not to technical right. So the we also nowadays do an O CT scan of the retina to make sure that the retina is intact and there's no other pathology that we can see. You can see on examination that you can't see on the examination of the patient, and this is what the oh CT looks like. That's the, uh CT of the Fovea. And as you can see, there's a nice dip and everything is smooth. So this this is a normal macula. There is no epiretinal membranes or sister had macular edema or age related macular degeneration present there. So we can reassure this patient that probably after her cataract surgery, the vision will be pretty good because there's no other pathologies on the on the macula. So the third thing is the cataract operation, and just quickly we went through the anatomy of the eye. But just to refresh your mind. Uh, there's the cornea at the front of the eye, which has got the epithelium on front stroma in the middle and the feeling on the back. Then that's the anterior chamber between the cornea and the iris. Iris is the colored part of the eye, Then the whole in the iris is called the pupil. Where the light goes through. The pupil needs to be dilated before you do cataract surgery and then the lens. It's behind the iris, and it's in a capsule, so the front of the capsule is called the anterior capsule. The back of the capsule is called the posterior capsule, and these are these O'Neill's that hold the capsular capsule today. I, uh, and you take out the front of the capsule scoop at the cataract from inside with what's called hydro dissection. Break it all up. It's ultrasound and then put an implanted instead of the lens that focuses the light on the cornea. Both the cornea and the lens contribute to this focusing power of the eye, so it's not just the lens. But if you don't have a lens usually, uh, the cornea would not be enough to bend the light enough or for you to see. That's why you need a plastic lens. Now, if you're very, very shortsighted, I'm talking about minus 18 doctors minus 22 doctors. Some of those patients'. If you don't put a lens in, they can see relatively clear because they're so short sighted. In other words, their their eyeballs are so large that they don't necessarily need lens. but we always put a lens in anyway. It's a good idea, even though the power of the lens maybe zero. Um right, So that's the machine. Well, one of the machines that can break up the cataract is and take it out. It's called fake or multiplication, and that's my It's controlled by a foot pedal that you can use to do the operation Cataract surgery. See what you're doing that the closer up. So it's got an assistant surgeon's viewing point, which has got the handles. And then the assistant can sit to learn. That's normally for people learning to do cataract surgery. And here we are using that knife. It's called the Claritin to make an incision in the cornea, and usually now we go straight through the cornea. We used to before go through the clearer when I was starting an ophthalmology, but now we've moved on to corneal incisions. Almost. You know, everybody uses corneal decisions, and there that's antique, absolutely stained and is being removed. That's called the Capsulorrhexis and tear capsulorrhexis, uh, using those forceps. Then you use a high a little bit of fluid or saline to do what's called the hydro detection. I don't have a picture of that. But you scoop out the lens within the capsule with some fluid injected just under the capsule, and then you use this apron multiplication. The thing is connected to the machine that, uh, causes the tip to vibrate about 2000 times a second and break up the cataract. So that's called fake and modification. And there it is, grooving the cataract and turning it around and then removing it all. And then you have to remove the soft lend matter, uh, with an irrigation aspiration port. So one of these is irrigating the yellow one and the yellow one, and then this one is aspirating. The soft blends matter, and the posture capsule here is completely clear. That circle is the anterior capsulorrhexis that you can see, and that's where you need to put your implant. So there's a fold that, uh, implant that's going in. And it is put inside that capsular bag and it unrolled. And this one is a terrific because it's got these three, uh, dots or four dots on each side to show where the angle of the tourist city is. That means the curvature of This lens is different, uh, in this direction, compared to 90 degree to that direction. And that's to neutralize the corneal astigmatism that's present. So that's been unfolded. And these etchings on the implant are to give diffraction pattern and we can call We can make patient's have pseudo accommodation. In other words, they can see with this lens both distance and close up, so it saves them having to wear their glasses. The only time when multi focal lenses don't work is when there is a low light conditions. Uh, then they have to put on their reading glasses, but in good light. It usually does work to focus the light, so that is another monofocal implant. And that's the size of the implant. Um, and I'm just going to quickly run through What's the time? Quickly run. Oh, we've done done to about 35 minutes, so we'll be finished in 10 minutes. Um, this is the size of the intraocular lens implant. Usually it's 13 doctors long from haptic to haptik, and it's about five and the optic, which is the circular part. So these legs from one end of the leg to the other end of the leg is 13 millimeters, and these optics are usually 5.5 millimeters in diameter. Um, so these are monofocal implants. That means they have one focal length and that can be set for distance or close. And then the patient wears glasses to focus on the other part of the with the other world of their vision. So they have only one focus. They can be set for distance intermediate, or to match up with the refraction of the other i f. The patient's only having cataract surgery in one eye and doesn't wish to have an operation on the other eye. And they can be used monofocal lenses in what's called mono vision. Wanna vision is where you put the focal length of one eye for distance object to see distance clearly and then the other eye for reading. So with both eyes open, patient's don't need glasses, and one I does the distance bit when I does the reading. If you're not used to mono vision, though, it can be quite off putting, and they can be unbalanced for six months or so, so you have to be very careful. Some people are already used to having mono vision with their contact lenses, which with one eye being corrected for distance and one eye for near. And if that's the case, then they shouldn't have any problem having the same thing when they go for their implants and cataract surgery and implants the most care vision because there's no etchings on it, they have less halo and glare effect than the multi focals. They have normal contrast sensitivity, and that's to do with how much you could see if something's just a little bit of white compared to white. That's contrast. Sensitivity, UH, standard. So they're the standard lenses, so they're cheaper than the other, uh, either toric or multifocal or toric multifocal implants, which are the special lenses. And they can be converted to a multifocal lens by doing another little operation and putting a piggyback implant in front of the original monofocal implant. And the good thing about the piggyback implants. Or they can be put in easily and they can be removed easily, but it's still an operation. Inside. The iron has the risks, but it's much easier than putting it inside the bag and removing an implant from the bag. So, uh, it's advantage of monofocal. So it's got one focus and that set for either distance, intermediate or near. And then you need to wear glasses for the other, for being able to see the other distances. Usually very focal. Vence it right So mono vision. We talked about one eye for distance, one eye for near the distance. I is usually going to be the dominant eye, and the near I is the non dominant eye now with dominant. If you want to all test yourself if you put your hands together like like this, hold it at arm's length and with both eyes open, have a put that Oh, at the center of your hands. And then, if you if I close my left eye, that always still in the middle of my triangle. If I close the right eye, the oh has shifted. So I'm right eye dominant. You can only do that and see which eye is your dominant eye. Does that make sense? I hope it does, right. Okay, so we said advantage of mono vision. It allows relatives spectacle independence, uh, using a monofocal lens, which is relatively tape. But the disadvantage is lots of depth perception because normally most people use both eyes to perceive depth. If you don't have one eye for a long time, your brain eventually adjust to having stereopsis or perceiving depth with only one I. But if you're used to having to eyes, then that's very important in depth reception and things that can happen is you go to pour a cup of tea. If you have loss of stereopsis is you pour the tea outside of the cup because you can't judge distances well. But if you have one eye eventually the brain does need. Learn to, uh, put the tea in the cup. So the second disadvantage is the feeling of lopsided, if one eyes for distance, one avenir. If you're not used to it, it's quite, uh, it can cause quite a bit of imbalance, especially when they're all their patients'. And then also, if there's any pathology affecting division of one eye, then the remaining I, uh, would have to have spectacles for seeing distance or near if that makes sense. Uh, these are historic lendings because they've got those etchings near the haptic. These three dots tell you the steep access of the implant and they have to be put at the correct angle in the eye. So they have to be dialed into the correct angle that you want them. Otherwise, the patient of the after the operate, I think, Mrs um is where the cornea and we're talking about corneal astigmatism now because, uh, the total astigmatism of the eye is there some of corneal astigmatism, the vectors, some of corneal astigmatism and lenticular stigmatism. And because the lens is being removed, you're just left with corneal astigmatism. So if somebody's got a lot of corneal astigmatism, usually more than 1.5 doctors, that it might be worth putting a, uh toric lens or finance stigmatic implanting so that they neutralized the corneal astigmatism and reduce their dependence on glasses. So, uh, total eyes, stigmata. Um, we talked about that, and that's their stigmatise them, where the focus in one direction is in front of the eye and another in at 90 degrees is behind the eye. So, uh, this is a mixed as stigmatism, right? So this is the Uloric implant being in the eye. And as you can see, they're putting. That's the steep axis of the implant um, multifocal implant. In fact, they can be order refractive multifocal implants or diffraction. I've the refractive ones didn't work very well, so most people are using diffraction. I've implants. Sorry. Excuse me. One moment. I just have to tell my kids to be quiet. Sorry about that. Uh, okay. So I think this is it. Oh, yes, there is a multifocal implant inside. I There's different types of multifocal implants, uh, that do slightly different things. But there's no point going through that. So they have more than one. Focus can be reflective or defective. They can be bifocal, trifocal or extended range. That's the subspecialty. It's, uh yeah. Every company just comes up with something new so they can sell. Their lens is basically but they're not too different from each other. And that's how deflection works. If you remember waves going through a single hole and then going through a sec, two separate holes can make constructive and destructive interference. And then you can have Perkin J images, which are secondary and tertiary images. That's how these lenses work to give you relative glasses free. Okay, so we've talked about the advantages being relatively glasses free, but the disadvantages of multifocal implants are that they can cause halos and glare. They can reduce contrast, sensitivity and increase the chance of a need for fine tune ING operation because of the inaccuracies inherent within the biometry measurements. And they're more difficult to convert back to a monofocal lens as you have to remove the original multifocal implant from the bag, which is a bit more traumatic to the eye than having removing a piggyback implant. Right, so this is a lend in a capital. After a while, the cells that that are sitting on the capsule have thickened and caused by bruises, and this patient has got posterior capsule thickening. That's like another cataract or what's called an after cataract coming on. And they will have laser to their eye and their vision would improve. Okay, uh, and if the lecture, I hope you have enjoyed it. And if there's any questions I'm very happy to take, I think there's 10 questions on the chat. I'm not, um I'm so sorry. I do have a question. Yes. Please carry out. Yes, it's regarding. Uh, it is regarding the all different types of cat tracks. But there is a total cat track. Why can't we use such, uh, laser in that instead of, uh, removing it surgically? Could laser be used in that cat track? No. There you can never remove a cap attract with laser. You have to manually remove. There's at the moment the things that you can do with laser. You can impulse if I the lens with laser, you can call Make the capsular, uh, the anterior capsule. You can cut that with laser, but you can't you you still have to. Then use something to remove the lens. That's been a multi stop by the laser from the eye, so that then involves surgery. So most people, because of the expense of the laser that mulches up the lens, use a fake converse fication, which is a lot easier and a lot cheaper to do, and you get the same outcomes. So with the total cataract, you still can do fake compulsive cation. So just do the operation. So I don't know of anybody doing just laser to remove a full cataract. There's bits of the operation you can do with laser, but not the whole thing. Are there any contraindications of cataract surgery like disadvantages of surgery itself. Yeah, so the everybody has a cataract. But if you got other problems, then you can have. Obviously, you're not solving those problems, such as wet age related macular degeneration. So, uh, sometimes if you haven't controlled the wet, age related macular degeneration that can get worse after cataract surgery. That's why you always do the oh CT scan. Make sure there's nothing else, but usually vision does improve somewhat, even though not as we measure it, but the peripheral. If they have significant cataract, there is an improvement in vision unless the vision of perception of light and they have got optic atrophy, which means they can't see anything because the nerve is not conducting to the brain at all. Uh, could the intermittent blurring of the vision, which is the eye surface disease, could be? It could be misdiagnosed as the cataract bleeding to surgery. That's right, Yeah, that's why you have to be very careful to take a good history and examine Well, yeah, so I surfaces is very common. So if it's intermittent blurring, that's I surface disease. And if you treat them with lots of artificial tears and let hygiene then you have saved them in operation. Thank you. Okay. Any other questions? No. Okay, then that's it. They're finished. No other questions. So I hope that was enjoyable. And if you like it, we can do some more some other time. And if you want any other topics that you're interested in, let me know, because yeah, it'd be good to know what your, um, interested in Thank you very much, Doctor. You're very welcome. Nice to me. See you all. Well, the ones who have got pictures on and, uh, yeah, have a good day and a good week. Thank you. Bye bye bye.