Lecture: How to Apply Scleral Lenses in a Pediatric Population

>> Good morning. I am Boris Severinsky from Emory Eye Center. I’m the chief of specialty contact lens service there. Today, we will be speaking about applications of specialty contact lenses and particularly scleral contact lenses in children. What do we know so far about scleras in children? I will go over this briefly, the literature. Basically up to date there are some studies about scleral lenses. Both of them were done on a prosthetic device, a large scale lens used for treatment of surface disease. And most of these reports come from [inaudible] of sight. And looking at the reports of the statistics, they are entirely for disease treatment like keratitis. These studies look — it’s a large group of patients. It’s hard to speak about large groups of patients when you see scleral contacts in children. But of course, to talk about patients under 15 years old. And to break down the studies is similar. So there was majority that were treated for ocular surface indications and about 13 to 15 percent were ocular — vision correction, like keratoconus. In recent publications from the last few year, one from USA and one from Iran, the studies look at smaller scleral lenses. The break down was a little bit different. In these studies, the majority of, almost half of the patients, more than half of the patients were treated for vision rehabilitation for cases like keratoconus or corneal scarring from penetrating injuries and 40 percent were treated for ocular surface disease. This didn’t show any evidence or evidence of keratitis which is good. So, why do we do sclerals in kids. For pediatric keratoconus which can be prevalent in different partings of the worlds. And traumatic eye injuries and support and hydration of the ocular cell surface. It’s also found to be useful in, after congenital cataract surgery and pediatric keratoplasty. In this presentation, I will bounce back and forth between the cases and the literature. And one of the studies, the Emory study on contact lenses in kids, I just wanted to share again, the design of the study was a retrospective chart review that lasted about two years. We did treat 24 eyes of 18 patients and all of them were under the age of 15. And the age break down was from 16 months to 14 years. The mean age of the treated group was about 11 years. So our groups were almost similar. We had 14 eyes are irregular cornea and — surface disease. Here is the age break down that you can see. We had one patient that was 16 months old. That’s the age that we started scleral lens fitting treatment. Now, let’s talk a little about what is available and what are the available types of scleral lenses for children. We will be talking about sealed contacts which is the vast majority now versus fenestrated scleral lenses. We will speak about how to pick up and choose the initial lens. If it’s better to use a base curve selection or sagittal depth selection. Of course, the size of the lens and the peripheral system of the lens, how do you make it stay over the patient’s sclera. And of course, what is the best way to put this lens in. As most of you know who is familiar with scleral lenses, there is a particular way you put it in the patients eye. With kids this can be challenging. Just briefly about what is scleral lenses and again it’s a large diameter, rigid, gas permeable contact that is fully supported by the sclera and doesn’t have any contact with the patient’s cornea. It also clears up the limbus and maintains a liquid reservoir between the lens posterior surface and the surface of the cornea. Lens is divided into three major zones. Optical zone which is the base of the contact lens. It shows refractive correction. The transition zone connects the optical zone with the landing zone. And the landing zone fits over the sclera aligned to the center and supports the lens. Speaking about different types, so looking back maybe 30, 40 years ago, scleral lenses just started. Most of the lenses were fenestrated. I don’t know who is familiar with that design for optical measurement. Basically, it’s a large diameter rigid lens that has a little fenestration hole. And this lens is inserted dry. You don’t need a liquid to place this lens which may be helpful in little babies or in cases where we cannot really keep a consistent face down position to insert the lens. The disadvantage is actually very much complex fitting. You have to do multiple adjustments and modifications. And right now, a very small number of labs that will be able to produce such a lens. And also the cost will be significantly higher. In cases of young children with pediatric aphakia, it may help because insertion of this lens is very easy for parents. Fenestrated lenses have optical fitting which is a corneal fitting of the optical zone or the scleral zone. The same idea for a regular contact lens, a scleral lenses lens to prevent contact with the cornea. To maintain healthy tear reservoir and of course, not allow the bubbles that come through the fenestrated optics to be big enough to block the site and cause desiccation. This lens is dry. It is a flushing of natural tears throughout the fenestration that improves oxygen levels to the cornea. Now, the contemporary scleral lenses are all sealed. You don’t see any fenestration of the lenses. At the moment, the lens is inserted basically very minimal to almost no tear exchange in between the surface of the lens and the tear reservoir and the surface of the eyeball. The advantages, it’s a huge amount of manufacturers and different designs available. Basically, there are all sizes from 13.2 mm up to 20.2 and larger scleral lenses. There is a lot of designs to modify the landing zones and optical zones with different additive things like [inaudible] micro — and there is a number of modifications. You can also, because the lenses have small diameter which is easier to handle by parents or children, kids by themselves. Disadvantages. Again, lens handling. It has to be inserted with saline and both parents and the child have to learn how to do that. The other disadvantages is the suction effect because of the fully sealed lenses. Sometimes if the landing — is fitted too tight to the sclera, it can cause suction and removal can cause emotional distress of both the parent and the child. How do we decide which lens should go in the patient’s eye? You can see the child for a corneal topography. But very often it’s hard to obtain a good measurement. Basically all of the decisions in very small kids are by looking at the profile of the cornea, or the profile of the eyeball which is easier to assess in very, very small kids. So it’s maybe based on external assessment. And we can differentiate between trauma patients and ocular surface disease patients. Usually in surface disease patients, we prefer to go with a larger lens to allow for better coverage and for healthier tears underneath the lens. In regular cornea patients, smaller lens will be good to get started. Remember, basically after the age of 7, the size of the cornea in children will be basically similar to the size of the adult size cornea. So in pediatric keratoconus — the regular size of the adult lens and we can — sagittal and the diameter. So as we said, the most rapid phase of corneal growth is from birth to about age of one and a half years. Cornea still changes and basically we can count the millimeter of change from age of one to age six or seven. Eyelid position and size of the palpebral aperture comes into your decision about the size of the lens. A rule of thumb is maybe starting with lenses up to 14 mm in diameter for ages 1 to 2. And then basically increase the size by 1 mm steps for every 2 years. As the child’s cornea reaches adult size, age 6 or 7, you can go with lenses of 16 mm and even larger. So just an example of 7 years old wearing a 16 mm lens in case of post HSV related corneal scarring. You can see the lens could be handled pretty easily. How do we — the lens. We can differentiate the landing of the lens speaking about tangential type of scleral curves or radial scleral curves. Tangential scleral curves, it’s easier to assess a good fit using the lens outs of the box. It’s basically a straight line with the patient’s sclera. The advantage of tangential landing curves is to reduce suction of pressure over the eye of the patient’s sclera. When we use the radial curves, that is usually [inaudible] depending on the size of the scleral lenses and depends on the design of the lens. But basically, manipulating the curves and as you can see here, this is an example of one of the lenses, you can see the difference in curvature throughout the landing. But the curvature of the sclera, you can create almost elliptical or spherical or optical surface but also following the size of the sclera precisely. What do we do regarding the materials? Of course, we will aim to use the most gas permeable materials. It’s called hyper DK materials. Every manufacturer now using a DK of 7 or higher for that are contacts. It’s common to get optimum [inaudible]. New materials that came recently have a decay if I’m not mistaken of almost 160 which makes it even higher. So the most readily available material I believe now is Boston XO2 but optimum provides slightly better oxygen flow. You may find wettability issues especially in teenagers and young kids that are prone to blepharitis. And lower decay materials might behave better because of the lower silicon percentage inside of the lens material. You can downgrade the material to lower decay going back to more — loss. Trying to solve this problem. Or a special coating may be applied to the lens. We can address the blepharitis in the patients trying to treat the surface first before we do material changes. How do we set it up? What do we use inside of the room and — basically it’s not different from fitting scleral lenses in adults. But there is a little bit of difference I would like to discuss. You need an extended trial set. You don’t want to use a scleral lenses with a power of minus 2 on someone who needs probably plus 16 or plus 20. Also, you should prepare the parent and the patient to what is about to happen because definitely the lens itself — even if you show it to an adult person, the lens itself looks pretty much stressful looking. The size. And especially so for a kid. They’ve probably been through surgery or ocular trauma and it can be very much emotional. So you have to be quick and address it carefully. What we usually do in cases that we cannot use a slit lamp, I very much like the blue pen light that helps to assess the lens immediately. For little kids, older than five I will say, you can do what I call dynamic OCT. They probably won’t be steady enough to stay long to assess a good image. But you can at least look at the screen or take a screen shot of the lens with your cell phone to review it later. Older kids can sit for a corneal OCT later on. I believe this child is about two and it’s easy to take an external photo using your cell phone just utilizing fluorescein and blue light. I just showed a little bit about the lens parameters. Always try to extend the set. Manufacturers will give you this. Some companies, I understand around the world you may be using local manufacturers. So I’m just releasing the ones that are available in the US. But most of the manufacturers today can bring all type of lenses from different places. You can always work with the local labs instructing them what exactly do you need and what diameter you would like to use. So it’s all adjustable. But you see a small diameter material and it can be done as small as 13.2 mm in the case of Essilor. For pediatric keratoconus or teenagers, you can do with an adult size lens. And high plus and high minus lenses are also very much useful. And don’t forget retinoscopy. Sometimes if you do — over a contact lens it will give you misleading information or just will be difficult to access. So retinoscopy in children with contact lenses is a must. How do we apply the first lens? Usually I like the parents to keep the child in their lap. I will show the lens. I will just basically do a short demo trying to apply the lens to a parent’s eye or bring it close enough to a parent’s eye to give them an idea what is going to happen. We do use a type of comfort drops. It’s a diluted version of ocular anesthetics. It’s diluted to 25 or 30 percent of the concentration. It doesn’t sting as much when you apply it but it provides a numbing effect for 5 or 10 minutes so you can insert the lens easier for the first time and prevent refractory tearing. We do use heavier fillers rather than saline. You can use everything preservative free like Celluvisc plus saline. You can tilt the lens but they still will feel it when you put it in. We do a flying baby technique for small children. The parents hold the child with their back up and just trying to move it back and forth and you just have to follow the child who is carried by the parent trying to put the lens in. Be fast and be quick and use the surprise factor. Just speaking to the child or the patient and let the parent know to bend the kid’s head over and down. Just in this example, I show you a video. Of course, she is not happy but that’s all. It’s done. So the quicker you are, the easier it will be going and then you can start your exam. So again, we touched a little on using some anesthetic before you put your first dry lens or diagnostic fitting. It also will help you to assess the prescription better because it eliminates tearing. And you can see the fluorescein pattern better. Use of a phone or tablet to make the child engage. You can put on a video or a cartoon to watch during the insertion. I like to put the tablet on the floor. Just maybe playing a cartoon or video and basically the parent will bend the kid’s head down and I will put the lens in. Be careful when you pick up your first measurement. It’s hard to tell what to use immediately. But maybe just go for it if you don’t see significant distortion to the corneal profile, go with the lower size lens. If you have too much sag, you might have some suction to the eye. And when you take it out, it can be very much emotional for the kid and especially the parents may be under significant distress when they see the practitioner cannot remove the lens. Try not to use too many measurement lenses because the child may not be cooperating for that long. I’m trying to get the fit from the first lens and even if the fit is not ideal, at least you know the prescription because you know the base cup of the lens and the retraction and you can adjust it later. Let’s touch on some cases. Going back to our study, almost 50 percent of our patients are patients with pediatric keratoconus and it can start very early in life. I believe one of the studies I read was 7 and a half years old with a significant case of KC. It’s more prevalent in the Middle East and areas where there is allergy conjunctivitis. You will see more prevalence of keratoconus. The reason probably is eye rubbing. Because the child’s cornea is softer than an adult cornea, because it’s higher turnover of collagen, it also may be responding to deformation of more, more type of it, more response than an adult cornea. Of course, no rubbing — the parent and the children has to be educated about no rubbing. Of course, because the cornea is softer and the progression is faster, you can see more scarring or more prevalent cases of keratoconus. So the sooner the kids are educated about no rubbing, the sooner we do any type of supportive procedures that we’ll discuss in a second, will be greatly appreciated in keeping the child’s vision stable. So it’s a case of 11 years old. No history of eye rubbing and had KCN for 2 years. We did do a trial fitting in the office. Actually the vision was corrected pretty good to 20/30. He is a little borderline I would say for cross linking. So here are the options. Maybe partial corneal transplant or full corneal transplant. Still trying to cross link contact lens assisted or epi off or on. So they fit the scleral lenses and this kid was cross linked a year later because he still kept progressing. I think this is very important statement by Chatzis and Hafezi ten years ago. They found that progression of keratoconus occurred in majority of the cases. There is no need to wait until the cornea gets worse and they have more scarring. Just a case of corneal follow up and progression follow up. You see in 12 years old female with mono-ocular disease, she did progress every few months. So a year ago it was 51 in the center and now it’s 53.3. And here uncorrected vision also dropped from 20/40 which is functional to 20/200. Again, speak about rubbing. No rub no cone. That’s a famous statement now. Another case of 12 years old from our cohort, my own study. He had allergies and rubs his eyes. The vision is bad since the age of 10. Glasses never fit him. You cannot do anything with the refraction. There is a prescription of 85 depth of the cornea. Not a good candidate for cross linking. Cannot tolerate RGP. He cannot stand his eye because he is so [inaudible] centrally. The next step, you place a PK or try a scleral lens first. The decision was to try scleral lenses, hold off the PK and he did great. His less deeper eye was 20/35 and he continued with the scleral lenses. Going back to our study. The mean keratoconus patient was 64. 7 diopter. Most had severe forms of the disease. They could not wear glasses or regular contacts and they did great with the scleral lenses. Also in four eyes with very advanced disease which K max of 75, the use of scleral lenses is obviated the need for keratoplasty. Keratoplasty can be a risky procedure. And the vision was corrected in 6 of them. Cross fitting and scleral lenses were fitted. The same applies here to pediatric keratoconus. The progression will be faster in pediatric KC. They should go through cross linking first and then scleral contact lenses should be fitted. Okay. Again, just discussing the risk and benefits of scleral PK and all of the studies show that the cross linking and scleral lenses are shown to decrease the rate of PK in keratoconus and same applies to pediatric patients. Another case from our study, he is 13. He had sudden onset of keratoconus and presented with corneal hydrops and DM rupture. He managed with hypertonic saline and steroids and cycloplegics. This is an acute presentation, of course, but it left him with a relatively small or medium sized corneal scar. But despite the scar, his vision was corrected to the initial acuity because of the flattening effect. You will find this especially in kids because the cornea is softer, the scar flattens the cornea and over time the scar also became less dense, like fading of the opacity and then we can achieve good visual acuity with the scleral lenses. Speaking about special population. We can also, special populations may be like down syndrome in kids with autism may have higher rates of keratoconus. This kid, one eye the vision was lost because of dense central scarring and hydrops. In the other eye, the parents were able to apply a small scleral contact lens and using a gel filler instead of regular saline. They were able to put it in without making him bend because they couldn’t make him bend. And again, we use dynamic OCT to assess the imaging throughout the exam without being able to capture it but at least you can take a picture with your phone and see it. Down syndrome, she is not really young but just to emphasize, again, scleral lenses could be easily worn in patients with — delay. If you have good support you can do these. Another example of a different scleral lens, it’s soft scleral lens. It utilizes a scleral support and if you can see it here, this lens is smooth, right. See the fenestration and actually the oxygen can move through the holes. This lens stays over the sclera and has minimal but still tear — this lens can be inserted dry. We can fold the lens and insert the lens folded under the upper eyelid. Here is a patient, again, with Asperger’s syndrome. He was rubbing his eyes from allergies. He was cross linked but should not achieve good vision because he cannot handle scleral lens insertion because of the complexity of the insertion. The fillers and the liquid and all the suction cups. We did try the soft scleral lens which he didn’t need to put liquid inside and he can get, he can wear that contact lens which is great. Speaking of PK. What do we need in PK. We need a good oxygen transmissibility of the oxygen. We need ventilated fit. You’re interested to get liquid underneath the lens and bring more oxygen to the cornea. Just another video. It’s not really sealed lens. They’re trying to go a little larger here but after the lens being in the eye for about an hour, you still can see some oxygen, some tear flow under the lens. So we can increase the oxygen levels. One of our patients with pediatric PK, this is a more complex case I would say. It’s not very typical. Four weeks old and huge dermoid. Underwent multiple surgeries and surface reconstruction and a patch and graft to recorrect the retinal surface. And after he healed he underwent optical PK. And this is how the eye looked after PK. It’s a huge [inaudible] on retinoscopy. Every attempt to place a lens was unsuccessful and it kept popping out. Just before giving up, we tried a small diameter scleral lens and it can stay and we can fully address this astigmatism. There are challenges in placing this lens. He had an episode of rejection but still we were able to take care of the optical correction and he is doing great. Another case, he is 11. This is trauma. He has traumatic glaucoma that is under control. And he can handle his lens by himself. He is 11 so it’s an adult size scleral lens. After two years, the graft cleared up which is great. Penetrating eye injuries, it’s very common. It’s very common and mostly affects boys as I may have mentioned. Most of the injuries, perforated injuries of the cornea — in the studies and I want to go briefly through some of the cases in our studies. So this child is 8. Corneal laceration resulting in corneal scarring. Irregular astigmatism. In his case the — is about 54. He also had cataract surgery and corrected visual acuity is 20/100. After scleral lens fitting, even with this huge scar he is 20/25 with the lens which is great. Another case of a ruptured lobe due to fall. He is aphakic. There is retinal detachment resulting in irregular sclera. You can see scarring. We did a fit of a large diameter lens and he is corrected to 20/40. So basically it’s very, you know, being aphakic and seeing the scar is the best way to [inaudible] the contact lens result before doing any combined type of surgery. Another case of corneal laceration from a sharp object. She is aphakic. The lens was expulsed. You see how heavy the scarring is. She didn’t heal well. And the wound was dehisced and it was re-sutured. And she has dry lenses. So we did four but maybe more than 20 training visits with her parents who were fine with getting the lens in and see how bad the cornea looked but the vision acuity is 20/40. In this case, again, it’s hard to tell even [inaudible] goes through PK, how the vision will be. But she is 7. She is 20/40 with contact lens. We do patching of the other eye to prevent anything else. And maybe for the next ten or 20 years the lens will work. Going back to our study, basically in almost all cases of penetrating injury of scleral lenses eliminated the need for PK. Another case, aphakic scleral lens. 4 weeks old. Congenital cataract. Already has megalocornea. Fitted with a RGP after cataract removal. Age of 6 months, the lens pops out from eye rubbing. And refitted with a 15.20 diameter lens and they are doing well. Of course, we need to overcorrect children. Again, just children in these ages, the scleral lens insertion and fitting is [inaudible] Of course, we will keep them slightly overcorrected. Working on the power slowly in keeping with the other eye. And probably the final few cases of pediatric ocular surface disease. We do see young patients with graft versus host disease or Steven Johnson’s syndrome or exposure keratoconjunctivitis due to eyelid surgeries or acoustic neuroma surgeries. We see many cases of blepharokeratoconjunctivitis. There is vision defect. Most of the cases prevent with a corneal opacity or irregularity. And speaking about our study. 8 patients were below the age of 10 which makes contact lens and scleral fitting challenging. We had three patients with NK. Mean visual acuity is 20/60. Again, let’s not forget amblyopia in this age is also a cornea opacification. But we could continue the scleral lens wear. It was a bit shorter because of the inflammatory nature of the condition. So it was shorter in ocular [inaudible]. All of them showed an improvement of the surface. And all of them the vision was improved. And no one showed any cases of microbial keratitis in our study. Probably most interesting case here she is six in 2020. And she had this nasty HSV keratitis of the central cornea. Of course the surface is very dry. There is stromal scarring with irregular astigmatism. That doesn’t change the scar. So she was fitted with a scleral lens that improved the dryness and the surface appearance. The vision is 20/40 and doing patching of the other eye. Look at the picture from 2020 and go to 2021 using scleral lens for a year. The opacity looks lighter and less dense. And then we go to 2022 and look how the cornea looks now. Just going back for a second, 2021, and 2022. There is some pigmentation in the literature also. And of course, the vision improved. There is some adulation in the literature that, I’m just giving this one for a similar appearance. But this is important to talk about. This report from Boston Sight showed improvement of corneal scarring in patients with Needham and Steven Johnson syndrome. Think about the protection affect and constant hydration, probably decreased the inflammation over the cornea. And the use of a lens may help the cornea, probably to have faster keratocytes or collagen exchange of the cornea. The scars in kids usually get better over time. Again, it’s maybe a natural process or a process that happens from the use of a scleral lens. Probably both are true. But we definitely see scarring improvement for patients using a scleral lens. There are a few cases of blepharokeratoconjunctivitis. This is pretty common. When the disease is active, it should be addressed with a steroid and eyelid treatment first. We do start scleral lenses early in these patients. Even if it just shows some signs of improvement for protection and separation of the patient’s cornea from the eyelid. And of course we give them prophylactic antibiotics. The scleral lenses serves as vision correction. In the time I still have, I will go through a few cases. So BKC, 9 years old tearing and photophobia from the age of 9. The condition worsened and presented with worsening surface. The vision was significantly decreased. Both sides has central opacity. We started scleral lenses and in 3 months she didn’t show any changes to the appearance of the gross surface and vision improved to 20/40. Another case of 8 years old recurrent chalazion. Going for a long time. She is on Restasis and doing all the surface treatment. On and off steroids and azithromycin for 2 years. Decreased corneal sensation. And central scarring and of course decreased visual acuity. And pretty much distorted topography. We did the scleral lens and the cornea improved and just bouncing back to show you this type of scar density before we started with the scleral lenses. And this is how it looked now. The vision is good. And she is able to handle insertion and removal of the contact lens. And very last one I would like to share, I just want you to see this video of the Steven Johnson’s syndrome patient. I believe he is 10 now. Look how easy he can do this. He has been doing it for at least last two years. Boom. It’s in. Speak about scleral lenses in kids, of course, it’s challenging and of course it requires time. But it is very appreciated. It’s a great treatment for both vision restoration and protection of the corneal surface. As you just saw, improvement of the corneal surface. It just needs time and proper education of both the child and the parent. And this patient will pretty much appreciate it. And let’s go to our Q&A: I have a question about minimum corneal thickness to proceed with the scleral lens. I don’t think there is any limitations for corneal thickness. If the cornea is compact and you don’t see an epithelial defect, you can proceed and have a scleral lens put safely on this eye. No other questions? Disadvantages. I will say it depends probably depends on the country. Some places the cost might be debilitating. Again, I can speak from the US experience, the coast might be debilitating and very often insurance companies won’t cover scleral lenses. Maybe you need to, it may take time to — a learning curve requires some time to learn how to — the lenses. Sometimes it’s more complex especially in the sclera has a pretty significant asymmetry. It can take time to learn how to fit it correctly. But again, comparing scleral lenses with gas permeable contacts, the main advantage is comfort. Also again speaking about the surface disease, it’s protective properties. Sometimes there in the initial cases of keratoconus, scleral lens might not allow visual acuity because of absence of full corneal contact. So sometimes we need a flattening effect from the rigid lens. I see over the last 20 years, especially as the lens fitting moves from rigid gas perm to scleral lenses and patients that are wearing specialty soft, many of them now wear scleral lenses. There is a question about Rose K semi-scleral lens. I believe the diameter is 13 or 13.2. So basically, it’s fitted over the peripheral cornea. [inaudible] minimal limbus and it doesn’t have the full support over the sclera. So it still has liquid reservoir and separation over the — cornea but it has some kind of contact over the [indiscernible] cornea. Limitation of scleral lenses. You cannot use on a surface that is really inflamed or you have a patient with PK with badly functioning endothelial cells. If you do put a contact lens on a PK patient and see edema or any beginning of swelling after maybe 30 or 40 minutes. I usually like to leave, when we do fit a post PK patient in a scleral lens, I tend to leave it longer in the eye to see how the cornea will respond initially. If you see any edema after about an hour, it’s a no-go. Probably a rigid lens would be a safer alternative. Yes, we can use scleral contacts for corneal scars. So basically, if the cornea had healed and again, the — is intact, it’s for vision rehabilitation. It will be a good option because it’s not just vision correction. It’s very often, again, just the presence of the lens and the bandage effect from the liquid behind the lens can help the scar fade away. The question is minimum age. One of the patients in our study was 16 months old. We do have two years old now. The aphakic patient. But basically, again, as long as you have parents that can able to perform insertion, you can definitely fit it. Just a minute. How long can we keep the lens in. For surface disease patients, it may be a bit trickier. So if they can do 8 hours and the eye looks quiet and clean and not making too much mucous. No increase in inflammation. We usually recommend to do it for 8 hours and then take it out if there is an option to take it out. If the child is at home and the parents can do it. Clean the lens and put it back in. If they can do 10 to 12, that is wonderful. Keratoconus patients, less is needed. If they need it for 12 to 14 hours for school, do it. We still need probably 14 or 16 as the max. But you have to work with the patients closely to see how they respond. How long does a scleral lens last? Ideally change it every 2 years or 2 and a half years. Not because of the changes to the lens shape or prescription probably will hold. The oxygen transmissibility, usually it will lose 50 percent of oxygen transmissibility goes down after two years. If you have a patient with corneal transplant, change its more often. If you have a stable keratoconus patient, the cornea looks good, the lens looks good, you can do 3 to 4 years. It may help to repolish the lenses. Many of them with keratoconus will have any type of allergic response with mucous. So if you can do some lens polishing, it may help to expand the durability of the contact lens. But again, I would say after 3 years it’s better off to change it. I’m just trying to go through these. No, the same question about corneal scarring. Yes, we also see the same in adults. That’s what makes — [inaudible] in adults the collagen turnover is slower than in children: But we still see fading of the corneal scars. Question about scleral lens for keratoconus. I believe Cybersight can address this question. Scleral lenses now, I believe it’s globally available. I’m hearing reports and looking at the literature and the reports now are coming from everywhere about using scleral lenses. So very good question about IOP and scleral contacts. It’s never been really proven with a large-scale study that the IOP goes significantly up. Most of the studies done on healthy subjects. The lens is placed and most of them, even the studies that show increased IOP, it’s very insignificant. About one point. So I will say it’s more about fitting of the scleral lens and not just the presence. If you do have a contact lens, it’s so tight around the limbus and you really see how does it make all the — all the limbal scleral and limbus cornea to come up because of the lens suction effect. So you can do some changes to the trabecular meshwork, at least temporarily because of the pressure effects. It’s more about not the modality but how the lens is fitted. What should we take for fitting — curvature. You don’t need the corneal curvature. It’s mostly about the elevation. You can base the lens fitting on the — it’s basically observation. And again, taking measurements may be challenging. That is why your external observation of the corneal profile will be much helpful. Again, use of fluorescein, use a pen light just to have an idea on how bright is the fluorescence so you can decide if you need to go closer. Some children of 3 or 4 years old can sit for a slit lamp exam. Antibiotics. It depends, if it’s just a surface disease with a punctate staining and we use a scleral lens, we do prophylactically one of the fluoroquinolones like Ciprofloxacin. One of the advantages of moxifloxacin, it’s preservative free. You can put a drop of Moxi inside of the scleral lens bulb. Steps in starting the scleral lens service. It depends where you practice. Different countries have different labs. But it’s ready everywhere. I believe you just have to talk to your regional scleral lens manufacturer to see what is available and many companies import products from Europe or the US. Over glasses, what is the advantage of scleral lenses over glasses. Sometimes you cannot just correct vision in glasses because the cornea is so distorted from corneal scarring or keratoconus. It will just improve, visual acuity more significantly. Okay. Advantages of scleral lenses over night. Yes, if there is a significant or non-healing defect or in patients mostly adult patients with pemphigoid disease or bad cases of Steven Johnson, we do use the modality of wearing the lenses day and night. Any type of exposure where you cannot really protect the cornea during the bedtime. We do use two lenses. The same lens, they wear one lens throughout the day. Take it out. Put it but the cleaning process. And they use the second lens that has already been cleaned to do it for bedtime and then vice versa. Of course they do prophylactic antibiotics in those cases. So we do not — we do pro-vied ortho keratology in our clinic but we don’t do it on kids because of safety. All right. I think we are good with everything. Maybe if you have maybe a minute or two, I just wanted to show you, I just put it inside of the presentation but how you can actually improve, I’m going back to sharing my screen. Oops. I just wanted to show you a little bit — a small tool what we can do for your patients. Especially kids trying to improve it. Improve the comfort of the contact lens. So I believe you do some modification in the office. We do roll and polish edges on all contacts. But this is just an example of a scleral lens and it’s important for everyone, adults, but definitely for kids to get the best initial comfort. Very often when they come from the lab, the lenses, they will have inter-displaced or knife-edge looking apex. It might be a bit too much for a child, the emotional distress and comfort levels to feel good about this type of edge. If you just roll this edge through a regular polisher, see how round it is now. This can remove a lot of discomfort on the patient’s eye. And again, speaking for both adults and children. So just maybe a little tip. And again, we did speak about the challenges so I will stop my share here. Maybe the last question, age, not really so it depends on the condition. If you need to use it for a case of aphakia or somebody with corneal transplant at very young age and the child cannot hold glasses or the surface of the egg is so much you can’t do glasses, in some cases there is no other option. I think we can stop here. Right. And thank you so much for your attention. I apologize for my voice. But I hope it was helpful. Thank you.