Lecture: Refractive Cataract Surgery: The Essential Steps for Planning & Preparation

>> Hi, everyone. This is Dr. Madhu Uddaraju from India. Today, we have an interesting topic, refractive cataract surgery. I will start sharing my screen. In this particular webinar, I would like to cover the topics of the essential steps for planning and preparation regarding the refractive cataract surgery. I have no financial disclosures. Before we start the webinar, just to test the amount of knowledge that you have regarding this subject, we have designed five questions. So try to answer these questions and we’ll have a post-test after this webinar again. First question is, who would benefit from a refractive cataract surgery? The person you see in photo A, the person you see in photo B, C, both of them or D none of them. You’ll have 30 seconds to answer it. Please go ahead and choose whichever is. Right. I’ll discuss the answers at the end of the webinar. Let’s go to the next question. Ten degrees of rotation in Toric IOL can cause how much percentage of under-correction in astigmatism? A, 10 percent, B, 25 percent, C33 percent or D45 percent. Right. Let’s go to the next question. If I expected post of refraction after doing 0.06D cylinder after your optical biometry and the ocular surface is not optimized. How much can it impact the final outcome? A, B, C, or D? Good. Let’s go to the fourth question. At which value of DLI, DLI means dysfunctional lens index, we will discuss this in detail. Would you consider a cataract surgery in a relatively clear lens with no corneal aberrations? 8 to 10, below 5, 5 to 7.9 or above 10? Good. Let’s go to the last question. In case you have a postoperative refractive surprise, when do you want to go in and exchange the IOL that you have placed inside? 4 to six weeks, wait for 3 months, 1 to 2 weeks, or 8 weeks? Thank you. Thank you all for actively participating in the poll. Let’s go through the webinar and take this poll again and see how much knowledge you have gained through this interesting webinar. If you see the outline of this presentation, we will cover the following headings. How cataract is evolving to refractive needs. How do we differentiate between premium and refractive. And the most important things as suggested in the title. How do you plan and prepare for the surgery. Understanding the patient, understanding the patient needs. Ocular surface optimization, biometry pearls. Managing astigmatism, IOL options, intra-op tips and mono-vision and the relevance today. And how do you manage postop refractive surprises. And key takeaways from this webinar. Let us take this under five headings. First, if you see how cataract is evolving as per the visual needs. If you see here, the classical definition of cataract, it’s an outpatient procedure done where you remove the eye’s natural lens that is clouded and replace it with a clear IOL. I have highlighted the point. Here we’re only restoring the vision clarity. This is what a conventional cataract surgery is. Is this the only thing we’re seeing or does it have a back story. If you see the natural crystal line lens has two main functions. One is focusing capacity and one is clarity. If you see all of us, we lose the focusing capacity at the age of 40. At a later age of 50 or 60 patients develop cataract and lose clarity. The question of cataract surgery is not only the cataract itself, but what happens to the lens in between the time it starts to lose its focus to the time it becomes opaque. What is happening in this time period. Cataract does not develop overnight. If you see there are certain changes that are happening gradually that will finally end up becoming loss of clarity leading to cataract. So this is where we’ll discuss about dysfunctional lens syndrome or dysfunctional lens index where you see a relatively clear lens but still the patient will be complaining of visual complaints. So the dysfunctional lens syndrome and all of us are taught during residency we should wait for the cataract to ripen or mature before doing surgery. But now, DLS reframes the lens as a continuum that fails over decades. Not an event that happens at a single time. Stage one is 40s to 50s where it loses focus. Stage two is 50s to 60s where it starts to become dysfunctional. And 60s is the stage where it turns white and that is when you see your cataract. If you see the vision dysfunction begins long before the lens turns white. This is what we all have to understand about the dysfunctional lens, if you want to know more about the refractive cataract surgery. So the three stage, what we’re looking for as I already told you, loss of accommodation, loss of clarity, and significant cataract. So in loss of clarity, though there is no significant cataract, the patient can still complain of glare, halos, night driving issues, light scatter, and lens opacification. Sometimes the complaints are there with a 6-9 or 6-6 part vision. That is when you have to make a call on whether to operate or not. I will not — do a clear lens extraction where the patient is not having a complaint. Here the patient himself complains of a problem despite the clear lens that you see on slit lamp. Here I will discuss more about the dysfunctional lens index in the preparation part. But now, before we take up refractive cataract surgery the three most important pillars of happy outcome are choosing the right patient. Choosing the right patient is more important than choosing the right IOL and performing the right kind of surgery, selection itself removing a lot of problems. If you don’t select the right patient, that is where all the problems will start. Next is right IOL, you match the lens to the lifestyle of the patient and not the marketing approach given by the company. And next is the right surgery. Starting from biometry to optimization, doing a capsulotomy, management of astigmatism. All of this comes under the surgery part. If you do these three things right, you’re going to have a very good outcome in the refractive cataract surgery that we’re going to discuss in detail. What is refractive cataract surgery? If you see, it is an evolution from a purely functional rehabilitation. That, we used to only remove pathology before. Now we have evolved into surgery where we give complete visual optimization. We’re trying to eliminate or reduce the refractive error as far as possible. In this model we have to treat cataract in the same expectation of lasix or SMILE. Here we have to compare the outcomes and benchmarking should be done with these kinds of surgeries rather than rehabilitation. The goal is no longer to give a clear lens but deliver a specific customized visual lifestyle resulting in less spectacle dependence if the patient desires. This is the whole aim of refractive cataract surgery. So if you see one I say the word refractive cataract surgery, you are all wondering these are the equipment that are required to do the surgery. No. You don’t require any of the equipment that I show you to do refractive cataract surgery. It is good if you have this equipment, they add value to the surgery but per se, they are not mandatory for you to do a refractive cataract surgery. One more — what happens when we talk about refractive cataract surgery and immediately the minds and the posters circulated by the companies, you see like this elderly people using a mobile phone, driving, playing golf or using screens. Of course we give them refractive cataract surgery, we have been doing that already. But please don’t be notion that refractive cataract surgery is limited to only these kinds of people. Actually, you can extend refractive cataract surgery to the rural population of our country also, they also have a very active lifestyle. If you see all the things they’re doing in the pictures, they’re having a very demanding intermediate and near vision work. They also have very active lifestyle when compared to the — elderly people. Here, if you feel that putting a refractive IOL is a problem or it has an affordability issue, here we can give an optimizing range of continuous vision by doing a mini mono-vision with the mono focus lens. And you can plan in LRIs and incision planning where they can’t afford — these options will be discussed in detail in the coming presentation. So refractive cataract surgery is not put in a single bracket where it’s only affordable by a certain class of patients. But it is something you’re going to offer every cataract patient that comes in the clinic but taking patient needs into consideration. If he is comfortable with glasses you’re not going to force glasses for vision for him. You go for a lens he chooses. But suppose the patient I’m showing you here is reaping the fields, it’s difficult to use glasses in this condition where he will be sweating and the sweat goes onto the glasses or the condition you can see they’re working in areas, it’s difficult to maintain the glasses. Here I think you have to think from the patient point of view and give them the best possible visual outcome after cataract surgery. Cataract surgery is an opportunity to remain the best possible visual outcome for that particular patient so that he has a good quality of vision and if the patient desires, we should try to reduce the dependency on glasses for his day-to-day activities. Now, let us see how you differentiate between premium and refractive cataract surgery. If you see a femto second laser, imported IOLs, optical biometers. Ocular surface analyzers. Intra-operative positive guidance. You can go for a femtosecond laser and if you don’t choose your outcomes are not refractive. Refractive cataract surgery you need not have an optical biometer. [inaudible] is good enough for you to get your IOL powers correct. The ocular surface staining is sufficient instead of the analyzers. The manual toric marking is good. The optimal surgical skill is good enough for you to place a good reck sis and put the IOL in the center. You can use mono-focal and enhanced mono-focal lenses and take the mini mono-vision. And here I would like to appeal to the industry, when we’re giving glasses for patients with astigmatism you don’t give them a choice. You write astigmatism glasses that come with cylinder. But that is not happening in cataract. If you see all of the lenses placed at a premium price that a lot of patients can’t afford. I asked the companies to put them as comfortable as a mono-focal lens to give good quality vision. Next the most important point is the planning and preparation. If you do this, 80 percent of your work is done. Here, before you go to the patient, you should be first convinced that refractive cataract surgery is the future of cataract surgery and you should have this growth mind set to come out of this conventional cataract surgery thing and try to customize cataract for every patient you look at. That’s the growth mind set you should have. And once you’re convinced you should convince the team. Just convincing yourself will not get things done. You should have your entire team aligned to the start this is going to have better outcomes for the patients. And that is when we all start rethinking from the patient’s points of view. Here personality is more important than pathology. Which patient you can comfortably go. The patient is happy with some glasses and trusts the process. He will ask good questions. Hobbies are working and gardening and golf. Good family support. These are the ideal patients. Patients where you want to rethink is higher jobs that require a lot of demanding visual, like engineers, pilots, photographers where they have high contrast. They want zero glasses and zero halos. This is a no-no patient. They have gone to multiple doctors but none are accepted. And family support though it’s not a direct thing it has an indirect role to play. If the man is not happy with himself he will not be happy with the lens. Suppose the patient is monocular, you don’t want to do refractive cataract surgery. So patient engagement. Always try to provide prior education material to these patients while they’re waiting in the waiting room so they undergo this education passively. They already know what questions they have to ask. Always try to look for personality types. Type A personalities try to avoid. Don’t give too many choices. I give two or three choices and ask them to chose which is best. Educate and never emphasize on particular lens. It’s the patient’s decision. Explain the surgery as a journey. It’s not a single stop solution. It may require multiple steps and sometimes there can be some residue that is left and may require a correction later or some power of glasses. Always prepare the patient that it’s a multistep process and it will take some time so they’re mentally prepared for that. 80 percent of them will be happen with the first instance but when you mentally prepare them for the journey, they’re happy the vision has come back. So we did a small survey of our patients where 85 percent of them wanted refractive cataract but only 8 of them could get it done. The main factor here that was avoiding the surgery was cost. So if you are able to get this cost out of the equation, most of them are willing to go for refractive cataract surgery. And also insurance related things will be there where you have to see whether their insurance is covering a toric lens, multifocal lens and all these things. Next, the patient education which I told you. You tell them that implantation of the refractive IOL is not the single step of the surgery. There is something called incisional healing where there is astigmatism and effective lens position variability will be there. Both of them together will, you’ll get something called healing blur. If you see I’m very cautious if I see the patient is reading 6-6 the first week. By the end of three weeks they can deteriorate. That is the healing blur. This is because of astigmatism and effective lens position variability. So usually if it’s very bothersome you can go for a correction after 3 months. Any capsular changes you can do after three months. Ideally go in early, don’t wait. Go in as early as one or two weeks or one month interval and tell them you give this lens 3 months of time for neural adaptation. And depending on the grade of nucleus, you can do in early but tear film optimization is important before you take up these cases. Now, continuing to the DLI I was talking about. There is equipment called — that helps us get this DLI information. I trace. If it’s between 8 and 10 it’s healthy. The lens is not causing whatever the symptoms the patient is telling. Here, the culprit is the cornea or the ocular surface. In these cases, don’t go ahead and implant your premium lenses or refractive lenses because the corneal surface has to be treated first. If you don’t treat that, the patient will never be happy. The most important thing here is dysfunctional lens, if the DLI value is between 5 and 7.9 but the patient has 20/20 or 20/30 vision, this patient is an ideal candidate for the refractive lens. They’re not seeing visual changes in the lens but the problem here, the visual symptoms is telling is not because of the ocular surface. It’s purely because of the lens changes that have happened. DLI below 5 is no brainer, you have to go ahead and do your cataract surgery. That’s the importance of knowing the dysfunctional lens index. If you don’t have access to ITrace, don’t worry, any of the abnormalities you can see. If you don’t have access to that, you look at the ocular surface. How you look at it I will show in the next slides. What are the other conditions where you want to do a surgery where you still feel the lens is relatively clear or lens changes are there. I prefer to do an early cataract surgery in case where is the ocular comorbidities are more. Suppose the patient is having a shallow AC, non-dilating pupil. Compromised corneal clarity, diabetes, hippocampus tension, zonular weakness. You don’t want the cataract to mature to increase or compound this risk factor. This is where I go in for cataract surgery even at the earlier lens changes. And also, patients are willing for ..(audio blipped).. that the — we can start doing this refractive cataract surgery. The nonnegotiable cataract surgery is refraction, manifest, try to find out the dominant eye. Optical biometry. You need not have an optical biometer, an ultrasound is good enough. Topo and tomography in cases of astigmatism. Ocular surfaces. Macular OCT. In these patients anything that you diagnose before surgery will be the patient’s problem. Anything that you diagnose after the surgery, the patient will invariably think it’s the surgical complication. And endothelium should be looked at and if you find the endothelium is compromised go in for viscoelastic and take all of the precautions and counsel for future — plasty that may be required. All these things have to be done routinely. Next is the adenexal examination. It has a direct impact on the ocular surface. The simple LLPP is look, lift, pull, push. Look for the base of lashes, blink position, tear meniscus, lifted the upper lid, look at the cornea. Pull for lid floppiness, push the lower lid and try to express the MG. Look for quantity and quality. Coming to assessment, you can see if the patient is symptomatic using some of the questionnaires. You can do the LLPP thing that I told you. Sustain with Lissamine green. If you see more than 5 corneal spots or 9 conjunctiva spots these are cases you have to treat for the ocular surface. Because most of them will be preop is subclinical but post-surgery they will become clinical. These cases usually you have to treat rigorously for 2 or 3 weeks and sometimes a month. Make the ocular surface table and only then take them for surgery. Why I’m stressing so much the ocular surface will be evident in the next slid. Suppose you don’t optimize the ocular surface, what problems will you have. Suppose there is a tear — pooling. It there is a central trispot, it will show falsely flat — apart from this you have [inaudible] specifically, spherical aberrations which will, the patient will be never happy despite the best lens you have output in the capsular — that’s the reason you have to — ocular surface stabilization the mandatory in all of the cases of refractive cataract surgery. After all, it’s the first refractive surface that comes into contact of light. And also this study was published as early as January 2026. They have seen 116 eyes where they look for dry eye and astigmatism. If you see, the dry eye group had .90 diopters of astigmatism and the control group .62. In a similar way, if you have the astigmatism predicted as.06 and don’t correct the ocular surface, it increases not four times or five times but ten times. If we have a.06 diopter that you’re expecting, the ocular surface is unstable, you have a.60 diopters of cylinder. That is how much impact the ocular surface can create if you’re not optimizing it. IOL selection formula. Most of you know this but I will tell you what we have been using. For all the regular cases, the Barrett universal tool is what we use. We have also been using the Kane formula. And hill RBF is also good. Barrett, if you can also have a AS — AT you have a more accurate measurement. Hypertrophs. KANE is preferred. High astigmatism, we go for a specific formula called Barrett toric or Kane toric. Ablufia Koch. You can try these but take your care readings from a topography with a — base projection and take the posterior corneal astigmatism into account. The Kane formula by default takes the astigmatism into consideration. The most difficult are post refractive. Here we have to use the Barrett true K formula if there is no history available. And the ASCRS online calculators which are predictable and formulas like Haigis and Shammas. Do biometry in the morning because it changes throughout the day. We prefer to do it in the morning and take those into consideration. Keratoconus is challenging. We use the Kane keratoconus formula. So coming to post RK planning. We have been using this ARGOS. I’m selecting the post 8 and accept. If you see this particular patient, has 3 diopters of cylinder. I’m not choosing — I’m going for a plain mono-focal lens. And size selector toric lens here. The toric is corrected. The astigmatism is corrected. So I think all the reason to — like the — they all have this so you can rely on their predictability and double check with the online calculators to make sure you’re using the right IOL. Next astigmatism management. Usually when it’s .5 to 1 diopter, we can use calculators and you can also to the femtosecond. .75 is a cut off for me. In these lenses we have to go in for — models. You have to correct to give good quality of vision in these patients. Astigmatism correction should be more democratized and more in an accessible position. How do you know you’re doing your toric in the correct proportion? If you have total cataract volume, ideally you should be doing 25 to 30 percent of them should be toric. 40 will be cylinders but some are not willing and some you can manage with ALRAs or spectacles. Taking that into consideration, if you have a proportion of 25 to 30 percent of the overall cataract volume, that’s a good thing to have. Coming to LRI and arcuate incision. They are good for smaller astigmatism corrections like .75. When toric IOL is not affordable and you can access this TPAC as well. The pitfall here is don’t overcorrection in low ATR. Patients hate the swing. Cutting too deep will create problems. Always verify the axis. Treat irregular astigmatism with LRI. Irregular astigmatism is very varied. The quality of vision will be bad because of the aberration and remember the nomogram and as per age do it. Astigmatism incision planning. In this particular case, if you see we collected a mono-focal. The patient has.75. Instead of doing LRM, just changing the main incision site from above to below. I came more temporal and the cylinder is .48. I will repeat the video for you in case you missed it. Here is regular incision. I go down, come to 0 and you can see the cylinder came down. You need not do a LRS routinely. Play with your incisions and most astigmatism can be taken care of. Also understand the surgical induced astigmatism. Most of you must have done it. It’s easy do it. But the most important thing to remember is don’t go by the — direction. Take the vector analysis into your calculation and only then you know the [inaudible] correctly. Next, the most important thing. The IOL choice. What is the, when do you implant a mono-focal lens with or without mono vision. Most complicated cases with ocular comorbidities like retinopathy, glaucoma, affordability issue, one-eyed paces. All these I think mono-focal is ideal and we need not do the mono-vision in these cases. And try to avoid these lenses in higher astigmatism cases and try to put toric IOL in such cases. Advanced mono-focals, that’s the default option we give for all patients now. You can also do a mini mono-vision for the second eye. Avoid it for higher astigmatism patients. EDOF lenses, for patients are active lifestyle with night driving. And type A personality because the lens is very forgiving. And we avoid these lenses in case of macular changes and glaucoma. Patients requiring proofreading, a near work person, Goldsmith, you can go ahead and do a trifocal lens where they have good quality of near vision. Here we try to avoid in type A personality and macular changes and glaucoma. All of these come with a toric addition. If there is .75EDOF we do it. In mono-focals the cut off is 1. Toric lenses we avoid in retinitis pigmentosa where you know the weakness is there. And post trauma. All these cases you put the lens in a certain angle but in the future, you don’t know how the zonules are going to behave. If there is going to be a tilt, the patient has a very, very bad visual outcome. In these cases the best thing is put in a mono-focal and give the astigmatism, so if there are any changes in the position of the lens, it will not affect the visual outcome in the long-term. So coming to incisions. I’m not a big fan of 2.2 precisions. So even if I’m doing a 2.2 lens, I usually go for a bigger incision, 2.4 or 2.6 where the ingress and digress become comfortable. The mechanical force causes more damage than the small incision. And you should have this good squarish thing at the limbus. When you do this, it should bleed and when it bleeds it will heal well. Proper hydration should be done. Coming to Rhexsis and toric markings. The size should be 5 to 5.5. If you have — good. Otherwise, you have markers you can mark on the cornea. Good centration is important. Corneal marking and slit lamp is good enough. Intra-op guiders are well and good. Mature cataracts, be careful because they will predict the way you have your lens. IOL implantation, in the back, well centered. Have a back up. The damage part is taken care there. If you don’t have a centration thing on your microscope, look for Purkinje image one and four. Four falls on the cornea and one is on the posterior lens. Try to get both in the center and make sure they’re in the center and correlating to each other. This is a simple thing you can see before closing the eye with the patch. Make sure the IOL is centered with the image Purkinje image one and four. In any case you have planned for refractive IOL and there is a complication, don’t hesitate to put mono-focal. Don’t think I have to place this toric, no. If you’re uncomfortable placing it, go in with the mono-focal IOL and place its. So always have your mono-focal as a backup and make sure counseling is done we will try to put this lens in for you but if that doesn’t happen, there is a regular lens that we will put rather than leaving the eye phakic or cause more complications later. The most important concept is the concept of mono-vision and the relevance in today’s scenarios. If you see mono-vision, it’s called omni vision, blended vision, all these. Cataract surgery has been used as long as 1985. What they do here is simple. They correct one eye for distance and one eye for near. Conventionally the dominant for distance and nondominant for near. Try to select patients willing for relative spectacle independence. Even your community outreach patients, they need not be denied refractive outcomes just because they cannot afford. So play with the lenses, try to give them a good mix of goodies tans vision, useful intermediate vision and near vision is not mandatory for most of their work. In which case this kind of treatment is not suitable is when the cornea astigmatism is more than 1.5, don’t do mono-vision. The patient has a strong ocular dominance. Large exophoria we will not do. Preop counsel. Have a plan. If possible, do a mono-vision contact lens try to show them how they’re going to see. Thorough post segment examination. Counsel for near vision glasses for fine and near work and dim lighted they have to use glasses. They may require a lateral vision correction. What are the types of mono-vision we are offering. Conventional not offering at all, because it’s too much. We’re no longer doing this anymore. Next is crossed and high myopes. You correct the dominant type for near and recessive for distance with a 2 diopter difference. This works well in high myopes. Hybrid, one lens, mono-focal and diffractive mono-focal. But the most commonly done are the mini or micro or modified mini. The dominant eye is corrected for distance but only.75 to 1.25. The modified mini the difference is 1 diopter. What are the advantages of mono-vision over mono-focal. Multi-focal every four or five years the lens change. They keep getting better and better. If they want quality of vision, put the advanced mono-focal and treat with the mini mono-vision to give them good quality of vision. When affordability is an issue, here this is more predictable. Better adaptation and patient satisfaction. If the patient is not happy, the correction is straightforward. You go ahead and do a laser enhancement. What are the limitations? There is a tradeoff, a decreased contrast, stereopsis. Impact on stereopsis. Sometimes the patients complain of asthenopia symptoms. Whenever you’re doing a.75 to 1. Most of the complaints don’t exist. It’s only when you cross 1.5 the complaints will start to pop in. In our experience we offer to all of the eligible patients and nearly 8 of 10 patients opt for this mini mono-vision. That is part of our surgical customization we give. Here we don’t take the dominant eye into consideration in our experience. Whichever eye is operated first, we go in for full emmetropia and the second mono-vision we customize. If they do close work, we keep it at.75. If it’s reading, 1.25 or 1.5. Second eye, if you’re using an enhanced mono-focal, you can reduce this correction by .5. Already spherical aberration is induced in the lenses. Here a .5 diopter difference will get the job done for you. And most important in the last topic that is relevant is how do you manage the postop refractive surprises despite using the best lens. Here the most important thing is going for a conservative approach. Give it time, give some time for the patient to get used to it. Usually, 50% of the time, the patient will be happy. When he sees binocularly it doesn’t make a difference unless it’s a huge refractive — I personally prefer the corneal based enhancements. I do it on the surface. I don’t want go in and touch the eye again. My preferred thing is a corneal based procedure. But some of them prefer to do lens-based enhancement, the inside fix. They exchange the lens. When you want to exchange the lens, ideally you do it between 4 to 6 weeks. Don’t go early. 1 to 2 weeks is not ideal. Here, the refractive error maybe because of glaucoma or retained visco. At least give it 4 weeks time you know it’s a proper refractive error because of the lens and then you have a lot of techniques. You the IOL and ultrasonic. You can attach the phaco machine and explant the lens and put in a new lens. You can also do the piggyback that is also available. You can put ahead of the lens that is already in the eye. These are different options you can discuss with the patient beforehand. When you tell them about this, they are mentally prepared. They know despite our best efforts, sometimes may have a problem and this has to be addressed at a later stage. The key takeaways from today’s lecture is cataract surgery is evolving. For and more it’s a refractive surgery. Offering good refractive outcomes need not be expensive. You can customize the lenses to the patient need. Proper planning and preparation is key for good outcomes. Mini mono-vision has good relevance especially when affordability is an issue. Post prizes will happen. Be judicious in choosing the corrective measures. I think that finishes the talk. We will go to the post test. Now I think you will be able to answer the questions in a better way after you have gone through the slide. So now you can tell, who would benefit from refractive cataract surgery? Excellent. I think most of you answer correctly. Both of them as we already discussed. Let’s go to the next question. Ten degrees of rotation in toric IOL can cause how much percentage of under-correction in astigmatism? Yes. So again, most of you have answered well. It’s 33 percent. So one degrees, 3.3 percent. 10 degrees is 33 percent. So let’s go to the next question. .06 cylinder. If you don’t optimize the ocular surface how much it can turn into? Excellent. Again most of you answered right. A lot of you have learned quite well in this webinar and 90 percent of you are answering in a correct way. Next the fourth question. At which value of DLI would you consider a cataract surgery in a relatively clear lens with no corneal aberrations? We discussed this and I think you can get it right. Actually 5 to 5.79. Below five you can do a cataract surgery but the lens has a cataract. So 5 to 7.9 is the critical gap where the lens is clear but the patient has symptoms. If it’s 8 to 10, it’s a different story. The lens is clear, the aberrations are not from the lens. Let’s go to the last question. In case you have a postoperative refractive surprise, when do you want go in for IOL exchange? Excellent. Most of you have answered correctly. It’s 4 to 6 weeks. I think that finishes the post test. Thank you so much. I think almost nearly 600 people who have attended this webinar live. I thank Cybersight, Orbis and Andy for making this possible. And I thank each and every participant for taking their valuable time out on this weekday. I hope the presentation was useful to you. ..(audio blipped).. questions so that we answer. Does every client who undergone cataract surgery remains with the IOL? Yes. How to determine IOL power in post lasix. That’s the true K Barrett formula that you use and the online calculator for post refractive cases. And like I showed you ..(audio blipped).. 700 — they have a thing you can use. What factors influence the choice of IOL? Patient’s lifestyle. The patient has an active lifestyle and happy with the intermediate vision. If the patient is near work, demanding near work, proofreading, go for a trifactor lens. Next, how do you define DLI? Dysfunctional lens index. Nothing but, you have (froze) relatively clear but the problem is because of the dysfunctional lens or the cornea or the ocular surface. In your experience, what is the most overlooked factor that can improve outcomes and procedures. That’s a good question. The most overlooked factor is the ocular surface. We tend to overlook it. If you do the ocular surface optimization well, most patients will be happy. Sometimes vision is 6-6 but they can say I have this irritation and I’m not happy. Those are all ocular surface problems. That is when you to do it. Next is Lisamine green. Yes, its will give you a wonderful thing. You need to put it in the conjunctiva and on the cornea. More than 9 spots in the conjunctiva, that’s how you have to look. I didn’t understand when to choose mini mono-vision. The patient wants to have a refractive outcome but not willing to go for a trifocal lens. For the first eye you go for — correct for distance. The second eye, you counsel him depending on the need, suppose he wants intermediate vision, you make him myopic .75. If there is more demanding near work, you make myopic of.75 or 1 or 1.5. You can decide depending upon the need. In place of mono-focal if you’re using advanced mono-focal, you can reduce this difference to .5. I hope I have answered the question. Regarding DLI, if you don’t — yes, that’s a valid question. It’s not available everywhere. You can do a simple topography. You can do with the slit lamp. IOL choice in higher astigmatism. You can choose any of the mono-focal IOL. I try to keep it mono-focal because already in these cases the aberrations are more. You don’t want to create more aberrations by choosing a — lens or trirefractive. Why avoid lens in macular pathology? That is something that is not going to be stable. In the future this is going to progress, the patient, because of EDOF lenses, there is compromised eye. In these cases I want to give the best possible quality. That is why I choose a mono-focal. 100% of light inside the eye and the macula is compromised so here we don’t want do it. Then we have how to manage post cataract refraction in children under the age of 8 and how to calculate. I don’t think I can answer this question. It’s best answered by pediatric ophthalmologist. I don’t do pediatric cases so I will leave that question but I hope you find an answer in Cybersight somewhere. Do you think angle of kappa will affect? Yes, that is one point I probably have — yes, it’s important. I feel your effective lens position, you can’t predict it quite well. That is the reason I don’t give much importance to kappa in my practice. Just a minute. Just before phaco what IOL power? IOL can be done with phaco. You do the phaco and do the IOL you can usually manage with the calculators. How do you calculate DLI. Which parts of refractive surgery planning is most important. The slit lamp, ocular surface, biometry. How do you manage mono-vision surprises. I wait for some time, I correct the second eye. As long as the (inaudible) the patient might prefer doing it on the surface. Otherwise, if it is, you want to go inside the eye, you have to go in as early as 4 to 6 weeks. Keratoconus. I think the formula Kane is good for this. What is the software you’re using to incision site? It’s built in the ARGOS that comes from the Alcon. You put in the incision size and positioning that software is in-built and it’s a planning system. You can take it on your desktop and plan it individually for every patient. Reduce cylindrical errors in SICS. Look at the steep axis and put a smile or a frown incision. Can you do mono-vision in irregular pupils? Yes. Of course. I think that is best preferred: You can go in after you finish the cataract surgery and do the single throw four-probe pupilloplasty to avoid photophobia. Why wait for 4 to 6 weeks in you don’t want to go in early also. Because sometimes the refractive change can be just because of the increased — or sometimes the corneal edema can be causing it. In these cases you want to make sure it’s because of the IOL. After two weeks you can go ahead and do it. After 6 weeks it becomes difficult because the capsule will start to become fibrosed to the lens. Can you elaborate what is the risk of capsular. I will — when you go inside, there is always a risk, your optic will come easily but the haptic, it’s designed in such a way it attaches to the posterior capsule. So in these cases I usually cut the haptics and leave them where they are. Remove the IOL and place a new IOL avoiding the area where the old haptics. I don’t pull out the adherent haptics but sometimes you can still have a — be prepared with a good three-piece eye ware where you place it in the sulcus. Lens exchange beyond 6 weeks would be difficult. Ideally you can do it any time after 2 weeks before 6 weeks. That’s the ideal time to do the lens exchange. Beyond 6 weeks we don’t advise. You go in and put piggyback IOL or a surface correction. DLI correction I have mentioned. How do you calculate IOL. Next pediatric patients. That is out of scope for this presentation. One eye mono-focal, best option for the next yes. You can do a trifocal if the patient is keen. There is nothing that both the patients — trifocal. We have done some cases and if the patients are keen and eligible for it you can do it. What should be the plan for correcting — I think this is one point I forget. Whatever angle changes happen, the toric IOL it’s important to make them stay for one or two hours and open the patch and look at the slit lamp and angle. If they’re stable for the first two hours they are less likely to get rotated later. If you feel they’re rotated in one week, you can go anymore. It’s not like the IOL exchange. You’re not removing the IOL. So you can go the third day or fourth day. If it’s more than ten degrees you can go ahead and put in your visco and gently dilate and make sure the visco wash is complete and that is how you can do it. Thank you for raising this important question. I am 50, male, 50 years of age is a good age where you can see early lens changes. DLI will also tell you. The only thing in high microns is you have to counsel for the problems of retinal pathologies. Now,n with the newer phaco machines where you call the myopy, the high myopes we do 25 to 30. Because of this, the chances of retina detachment come down. Still, you have to tell them the chances are there. In these cases, you can go ahead and do your regular mono-focals and manage, always keep the myopes at .5, .75 only. So they will be happy for the near vision also. Pediatric patients, we have answered that. Once already patient has IPCL, that’s a good question. I think an IPCL or any phakic, there is no change. Most of the biometers take this into account. So your IOL power is not going to change because of the phakic IOL. You can calculate it like a routine case. Common causes of refractive surprise. I showed a slide how to calculate the SIA. Depending on that you can fine tune. Any significant different outcomes — I told you, optical biometry is superior. But if you’re doing a good ultrasound, scan with immersion you get good readings. I think maybe the error percentage would reduce farther if you’re using a good optical biometer. But where the media is not clear, the gold standard is A scan with [inaudible]. Albinism, in the cases where you have comorbidities it’s better to go for a regular mono-focal in both eyes. Then give them glasses over that. Implanted nystagmus. I would not do that. In the case of comorbidities don’t compromise on the lens design. Go for the mono-focal which still today is the highest form of thing that goes in. Dominant type concept is a bit outgrown today. In our practice we don’t see for the dominant type. Whichever eye we’re operating first we go for the ametropia. The second eye, we try to keep it myopic. I have seen cases where I have gone to U.S. conferences and I think they’re doing well. Three chances for you to correctly power the lens with the help of a laser. The patient has to avoid sunlight and all. I think that’s a definite thing you can do. ICL for myopia. Yes, ICL for younger patients is a good option. Once they cross the age of 45, 50, no point putting in an ICL. You go and counsel the patients for refractive lens exchange. Especially if you have the [inaudible] lattice. In cases of IOL for lens exchange which formula is better. Capsular phimosis has happened. The previous IOL, if you see and the refraction is good. No need to change. But it will be difficult for you to go in and put it in the back. Here you have to calculate the lenses for your sulcus. Maybe a.5 difference you’re able to do it. For sulcus it should be good. Incisions can have a good impact and you can have less astigmatism. Thank you.