Lecture: Introduction to Pediatric Low Vision Rehabilitation

Visual impairment and blindness in children requires a comprehensive functional vision evaluation to assess. An introduction into case history and examination modifications as well as prescription of assistive devices will be discussed, and referrals to rehabilitation professionals to enhance functional outcomes will be reviewed.

Lecturer: Dr. Karen Squier, Associate Professor and Chief of Low Vision Services, Southern College of Optometry, Memphis, TN, USA


DR SQUIER: Okay. Good morning. My name is Karen Squier. I’m the chief of Low Vision Services at Southern College of Optometry. And I am primarily hoping today to spend a little bit of time with you to talk a little bit about kind of getting into pediatric low vision. It’s a topic of clinical care that’s very important to me, and I think important to a lot of us, and I’m hoping to kind of teach you a little bit about some of the things that I do, and maybe kind of give a little bit of idea of some ways to kind of approach your exams. When we’re looking at objectives for today, just for this short course, short time that we have together, the hope is that we’re gonna have a little bit better understanding of the epidemiology of pediatric low vision. Have an idea to implement adaptations to traditional exam techniques for the pediatric population. Understand considerations of prescribing devices for the pediatric population, understanding the implications of pediatric development in developing a pediatric rehabilitation plan. So that’s kind of some of the things that we’re going to go over as we’re working together today. So to kind of get an idea where we’re all at, we’re gonna start with a poll question. So this is the first question of the day. The question is: What experience have you had with managing children with visual impairments or blindness in clinical practice? And we’ll give everybody a few seconds to answer the questions. Okay. So it looks like we have a pretty good range of experience. The majority of people, about 61%, say I see some children with low vision in practice. There’s a few that have never had experience, and there’s kind of some that practice more with adults, and a few that are very familiar with pediatric low vision. So hopefully we’ll be able to kind of get something through this lecture that everybody is gonna be able to take away from today. So the first thing I wanted to talk about was just kind of the epidemiology of pediatric visual impairment. It’s a very important component to go over, because it kind of dictates what services and what’s available for children. The hard part is that the true numbers and the actual epidemiology is difficult to track, because each country uses a different system to track children with disabilities. Some countries use register of children, some are using clinical data, so the actual true number of visual impairment differs kind of how each country submits their information. Also, sometimes how we define visual impairment may differ among different countries. So that can make kind of a little bit of a variation as well. Using just the different level of acuity or different components like visual field issues may make some challenges as well. And then lastly, sometimes we lump the low vision and uncorrected refractive error into the same category, and when we’re talking about low vision, we’re essentially talking about visual impairment that remains after the refractive error is corrected. So if we lump in uncorrected refractive error, it does kind of change the scope of the numbers that we’d be seeing. There are some important trends to kind of take a look at, first off. Cortical vision impairment as a diagnosis is increasing. Medical care is improving dramatically for kids that have brain injuries, so the survival rates are improving, so we’re now having a population of children with this condition that is surviving, and then therefore increasing that need for rehabilitation. Additionally, nutritional causes of visual impairment are improving in some areas. Access to care is improving. Especially we talked a lot about vitamin A deficiency as being a very significant cause of visual impairment, and by getting some treatment and care in that realm and kind of having more nutritional care, that does improve some outcomes. And then lastly what we’re seeing is the prevalence of visual impairment is correlated to socio-economic status. So there are certain countries that may be more apt to report higher levels of visual impairment due to the socio-economic status. That’s helpful to know, because when we start targeting areas that need rehabilitation or need assistance in getting more care, we can kind of at least get an idea of where we need to target some of that effort. We’re looking at the overall prevalence of registered blind individuals. Children kind of come in about 2.2% of registered blind individuals, and about 1.3% of partially sighted individuals. So it sounds like a low number, but these are people that are gonna have a visual impairment throughout their lives, so that visual impairment is cumulative over the course of time. So these are people who are living with a visual impairment for a longer time. And we’re looking at the World Health Organization. They do a lot of great information about kind of statistics and kind of assessing where we need to kind of look to change our strategies, and one of the things that they have noted is that low income countries with a high under 5 mortality rate — the prevalence is 1.5 per 1,000 children. With higher income countries with a lower mortality rate, prevalence is much lower. About 5 times lower. So that’s a significant difference, just kind of looking at two factors: The income of the country, as well as mortality rates of the 5 and under children population. And the estimation is about 1.4 million children that are blind worldwide. So that’s a pretty significant number that we need to kind of work at, to make sure they have low vision services. We’re also looking at the epidemiology of children’s blindness — we kind of can use this study to kind of help out with figuring out what types of conditions we’re more likely to see in practice. And depending on the socio-economic status, kind of right here — the higher end — what we’re gonna see are more conditions like retinopathy conditions, conditions that may affect the optic nerve. For the lower income countries, we may be more apt to see a difference in the shift of prevalence. And one of the things to look at here are corneal conditions. Vitamin A deficiency is one of the leading causes of visual impairment, and it creates a lot of corneal scarring, so we may see higher corneal. Here we go. Corneal causes of visual impairment. I kind of cut it off a little bit here too, but also lenticular or cataracts. Some countries have better access to surgical care and better access to their eyecare provider, so some of those treatments may be initiated where in other countries they’re not quite as available. So access to primary health care, making sure that that child has general overall development in their clinical development. And we’re also looking at the different income levels of different countries. High income countries — the more common causes of visual impairment are retinopathy of prematurity, teratogens or those types of insults to the maternal development that can cause problems with fetal development, cataracts and glaucoma. If we kind of shift down to the other side, where we’re looking at some of the lower income countries, corneal scarring, again, by far outweighs all the other causes of visual impairment. So really looking at the access of care and nutritional status of that child. Just a couple quick graphs here. When we’re looking at the overall number of pediatric blindness, the highest percentage of where those children are are in very poor countries. Almost 40% are in countries that have the very poorest health care services. Access to health care services, I should say. And when we’re looking at trends overall, throughout the world, we’re also looking at retinal causes as being the most common cause, and then corneal scarring comes right in behind it, as well as overall development of the whole globe. So kind of looking at that information, we can kind of get an idea of what type of impairments some of our children might have regionally, and how we might need to change our rehabilitation plan. I have another poll question to get an idea of also where we’re at with this. In your practice, what is the most common cause of pediatric low vision that you encounter? Corneal disorders, cataracts, retinal disorders, hereditary disease, cortical impairment, or the ever-ubiquitous other? So it’s kind of a mix across the board. The most common, 32%, is retinopathy of prematurity, or retinal detachment. Right behind that is cataracts, at 27%. We have corneal disorders at 11%, hereditary disease like albinism and RP at 14%, and cortical vision impairment at 16%. So a pretty widespread of the different conditions that we kind of expect in the pediatric population. For people who had registered for this webinar today, I made a little graph of kind of where we all are coming from. And we have a significant — a little bit over a third are from Asia, a little bit more from Africa, and then kind of throughout the other different countries — excuse me. Not countries. Continents. It’s a little early here in Memphis. For the different continents. You can kind of see where we’re all located. So it doesn’t match up as much as I thought it might with some of the different conditions, but it’s kind of just an interesting correlation to kind of take a look at, while we’re here today. So when we’re looking at why are the numbers important, there’s a few reasons for that. One is: The services that are available for kids in school, in government services, it’s gonna be targeted by how many people are actually registered as having a visual impairment. So we need to make sure that we do have an idea of how many children are visually impaired, so we can make sure they can get access to the care and make sure we have funding to support that care. The other thing is that we need to kind of start changing how we look at children with visual impairment as what they need for the year that we see them or the time that we see them, but more related to how long that child will live with the visual impairment. So a four-year-old who has lost their vision is going to be visually impaired — if they live to 70 — for a much longer time than somebody who loses their vision later in life. The reason that’s important is we need to make sure we have proper assessments and make sure that we have proper support for that child, and to kind of develop throughout their childhood and their adulthood. The other thing is we need to make sure that we have appropriate resources for development and access to technology. That’s a very important thing to consider as we’re working with kids, and especially young adults. We need to make sure that they have everything to keep them up to pace with their normally sighted colleagues. And then lastly, when we’re looking at appropriate interventions, we have to make sure that we’re looking not just at their visual acuity, but also their overall development. Their social skills and how they interact in society, economically we know that people that are visually impaired have a tendency to have a higher unemployment rate and maybe not make as much money as their normally sighted cohort, and also psychological assessment as well. Making sure that mental health is addressed with kids and adults who have visual impairments. So we need to make sure we have an idea of kind of where everybody is coming from. The other thing — I found this article that was way back from 1977, 1978, so it’s a long time ago, but it is kind of an important thing to look at, because it kind of gave at least an idea of where… Let me just move this out of the way… Where kind of the funding goes to, for kids that have a visual impairment, while they’re in school. So this study looked at how much funding and how many resources are kind of available for kids that have visual impairment. So for somebody who just has a handicap, and that would be just visual impairment that affects their ability to do daily activities, it’s a little over two times the cost of what it would be to educate a child with normal vision. If they become functionally blind, it’s 5.68 times more expensive. Functionally blind and having an itinerant special education teacher, so somebody hired specifically to help them be able to kind of succeed in the classroom, much higher. 6.78%. In 1977, the overall cost per child was a little over $11,000, but when we adjust for inflation, the cost goes up to about $50,000, which is a significant amount of money when we have to consider how many kids in the world are visually impaired, and how many resources we need to take a look at with them. So we spent a little bit of time looking at kind of the demographics and the epidemiology. We’re gonna start going into the examination. And the first thing that we want to do is, when we start the examination, kind of see how that child behaves kind of in a new or novel environment. So you want to do some observation of how that child is behaving. The other thing is you want to make sure, in your exam room, that you don’t have too many distractions. Additional distractions that are gonna make it hard for that child to attend to the testing that you’re gonna be doing. So you want to make as little distractions as possible. You want to take time to kind of just observe how that child interacts with the environment. For a child that has nystagmus, they may have a head turn or a head tilt that they use when they’re looking at something of interest. Additionally, as that child moves throughout the room, how do they adapt to visually challenging objects? Do they move closer to it? Do they find a way to get closer to that object of interest? Do they avoid it altogether? Or is there any squinting or closing of an eye to kind of make sure they’re using only their better-seeing eye? You also want to see how that child responds naturally and normally to glare and lighting. Some conditions like albinism and achromatopsia — kids are super sensitive to light. So that might be something that you start to notice, if they kind of put their hand over their eyes or they kind of squint a little bit more. It’s important to kind of make sure you assess that, without kind of — just kind to seeing how they handle that naturally. This is from a clinic that I did. So I broke my own rules. I was between patients, and I had everything that I own, apparently, out on this table. And this little girl, who was at the table, was so fixated on what my stuff was that she wasn’t able to attend to her other exam. So it’s one of those things where I say do as I say, not as I do. But this was a good lesson that I learned. Make sure that you clean up as you go along, because any distractions will distract the child from your exam. Some other observations that you may notice before you start your examination are what we call manneristic behaviors. They used to be known as “blindisms” or kind of just some movements or kind of repetitive behaviors that people with visual impairment — kids with visual impairment might display. Kind of as they’re in their natural environment. It’s not really something like a head turn or a head tilt in response to a nystagmus. It’s more to kind of slow that nystagmus down and kind of improve vision. Blindisms and manneristic behaviors don’t really have a purpose. There’s not anything to kind of improve vision. It’s kind of just a repetitive behavior, more as a coping strategy and an adaptation to vision loss. When people do display these, it can relay into reduction of quality of life. It is something that’s different than other children their age are doing. And it may relate to children being treated differently, bullying, those sorts of things. So it does have an impact on the overall quality of life. Some common manifestations that you may see are body rocking, where the whole body is moving from side to side or front to back, eye poking — children sometimes poke their eyes to get a response to the phosphene. Head banging, kind of banging their head from side to side, finger waving, and then also light gazing. Kind of staring at bright light. So these are some manifestations that you may notice when your child is in your room. Sometimes a level of vision might relate to the types of behaviors that kids exhibit. Visually impaired kids might poke their eyes or stare a little bit more. Also some body rocking you might see with that. Kids that are totally blind sometimes have a few different mannerisms, and it’s more likely they’re gonna pursue activities that kind of elicit proprioception and vestibular behavior. So more body rocking. More head shaking. That sort of thing. There’s not really a treatment to kind of improve the manneristic behaviors, and typically kids grow out of them. They may not grow completely out of them, but they may reduce their perception over time. The thing is to try to work with parents, because it’s hard for parents sometimes to understand what’s going on. It’s just to kind of find a way to substitute another form of stimulation. And that way, that child finds another outlet to kind of get that stimulation through other purposes. This is not really any recommendation for psychotherapy or aversion therapy, because it’s not found to be successful or effective. And another thing you might want to talk about with your parents and patients is just that the more disabilities a child has, a multidisabled child may have mannerisms much longer and they may persist into adulthood, just due to lack of development. So just some things to keep in mind as you’re working with these children. So we start with the case history. Case history is probably one of the most important parts of the examination. You want to make sure that you can get as much detail to put yourself behind that child’s eyes and kind of see what their environment looks like, so you can kind of predict any difficulties they may have. So your attention needs to be spent more on a child’s daily routine, which is much different from the adults that we may see. Things about the home environment, school, hobbies, and sports — all very important. Those are the big three that we kind of look at with kids. We also want to look at everything in between. Like getting ready in the morning. Sorting clothes. How much independent stuff is that child doing. Additionally, when you’re asking your questions, they should be specific to a child, like visual complaints, level of independence, as well as support for performing tasks. A lot of kids are going to have help with activities that we are hoping for them to be proficient in, but things like getting a meal together or getting their clothes ready — they may have a lot of help from their parents. But as the parents and the child start to work together and the child becomes more independent and older, they’re gonna need a little bit of help on how to transition, how to learn those different tasks. So it’s good to get an idea, as you’re going through, how many different tasks that child is able to do independently. We’re talking about school. Children spend a lot of time in school. So it’s good to get an idea of what problems they may have encountered. One of the big issues is copying information from a blackboard or a whiteboard, information at a distance. It’s good to know what kind of strategy that child uses. A lot of times we suggest walking up to the blackboard, and a lot of kids are allowed to do so, but other strategies that aren’t quite so great are copying from their friends or taking their friends’ notebooks home and making notes from those. So those are some things you kind of want to figure out — how is that kid getting that information that they’re needing to learn in school? Other goals that students may have are reading textbooks like their peers, so using a traditional working distance, rather than bringing things so close. So that may be a goal or issue that your child is reporting during their examination. Are they using any accommodations? Are they using any magnification? Are they using large print? What else are they using to kind of help them read their textbook as a peer? And then handwriting or drawing. Handwriting may be a good indication of how well that child is able to write on a straight line, how they’re able to kind of get their homework done. But it’s also one of those things that we need to kind of take a peek at, to see how that child is doing. Because a lot of handwriting and drawing are parts of especially very young development. It also helps us understand kind of what that child’s spatial awareness is. Because that way we kind of have an idea of — just in their local space, but also in their global space, maybe that child may have some spatial awareness issues that may be addressed with orientation and mobility. So we’re looking at the history of low vision devices and services. It’s important to kind of get an idea of a few different things. One is the services that child is getting in school, and what year did they last get that service. So a lot of times, a child might get orientation and mobility when they move schools, or if a problem is identified. It may have been a while since that child’s gotten mobility issues and they may have had new issues. So it’s good to know kind of how old they were and what services they got. And how they worked out. What were the outcomes and any additional referrals that child may have garnered with their training that they got. Additionally, when we’re looking at low vision devices and accommodations, what are they using currently, and what have they used in the past? And what’s been working well? And what’s been a failure? It’s not uncommon to find a device might work well in a clinic, and then they get to school and find it’s not quite as functional. So it’s good to get that feedback of kind of what worked and what didn’t. Other visual difficulties as well, depending on the patient’s ocular condition, you’re gonna have some predictions of issues. Somebody with albinism, for instance, is gonna have problems in brighter lights. Kind of looking through your observation, your history, you’re gonna have an idea of some other difficulties that may come along with specific conditions. And it’s good to ask questions about glare and light sensitivity, night blindness, color vision issues are very important, especially with young kids, because a lot of their world in kindergarten and younger grades — there’s a lot of colors that teachers use. So it’s good to kind of get an idea of what that child’s development is, so that we can relay to the teacher what colors work and which ones don’t. When we’re looking at visual goals of children, children typically have different goals than adults. And one of the ones that we’ll kind of see in our clinic is that kids have more of a goal of improving their distance vision. And that’s more related to kind of being in the classroom setting, and different types of social goals. If a child goes out on a field trip, and they go to a zoo, it’ll be much harder for that child to see the giraffes and elephants from a farther distance. So that might be something that we kind of talk about with kids. What kind of goals at a distance they might be able to see. As kids get older and their work load changes in school, reading becomes a much more prominent goal. So reading goals typically increase with age. A child in kindergarten is gonna have a shorter task goal, where somebody in 6th or 8th grade may have more prolonged and sustained reading. So it’s important to kind of take a look at how that child’s development changes, how they’re able to achieve their goals, and what their goals may be, as they come in from year to year. So once we have our history, at least an idea of our history and where we’re starting at, the next step that we’re gonna look at is visual acuity testing. And with kids, we have to kind of make some modifications, because there are a lot of different tests that are available, to figure out what the best one is gonna be for that child. When we’re looking at test selection, how we’re gonna test our child, it’s important to look at a test that’s gonna be developmentally appropriate for that child when we see them. Because if we choose the wrong chart or choose a chart that’s too difficult, you’re gonna get a lot of false negatives, and so what can happen in those situations is that you’re gonna get wrong answers or a worse acuity, when actually the test just may be too difficult. So it’s good to kind of test your child’s response to optotypes before you even get started. So this chart over here is our Lea symbols. We use this a lot with kids, because it has very crisp and very specific shapes. We have a key card that’s over here, that if a child maybe is a little bit shy, and they’re not happy to tell you what they see, they can at least point. So if you ask them to see what they see up here, they can point to that house, and you know that they can see it and match it properly. One other issue is this little guy here, the heart, some people call it an apple. Some people call it an apple. Some people call it a heart. It kind of goes back and forth. So it’s one of those things to kind of get an idea of what that child would name all of those, before you get into testing. On the right is our Allen optotype size. And when we’re looking at different shapes, these are a little bit old school, but they still work well. But some of the challenges are things like this phone here. A lot of our younger kids may have never seen a phone that looks like that. We use a lot of smartphones or other types of things. So this may not be a phone that is quite as common. So it’s good to just kind of review that, before you get into your testing. So some things that are gonna factor into your visual acuity measurements are the types of procedures that — the procedure itself, your testing distance is very important, typically for younger kids I test at a closer distance. And that way, we minimize distractions in the room and can make sure that child is only attending on that one task. So testing at a closer distance. How quickly and how you present your optotypes is also gonna have an impact. You want to take your time with this, because some kids are very quick with testing. Some of them are a little bit shy and a little bit anxious, so they’re not gonna be able to attend very quickly. So you want to take your time. What we know also too is visual field status and lighting is gonna have an impact on your acuity measurement. So it’s good to kind of consider the pathology when you are doing your testing. So to make sure that if you need to adjust lighting or adjust the presentation of your targets, to make sure that you do so as you’re doing your testing, or you may get some false negatives. And then lastly, your child’s response to patching or occlusion. We’ve all had that situation where you patch a child and they get very anxious or upset. So it’s good to come up with a system that’s gonna reduce anxiety as much as possible. Typically what I do is I test both eyes together, and then that way the child is just using their natural vision, and then if I know which eye is the better eye, I test that eye next. Typically when you patch the better-seeing eye and the child has to work with their worse-seeing eye, they get very apprehensive, and kind of get a little bit anxious. So it’s important to be able to reduce anxiety as much as possible when you’re doing your testing. There’s a few different charts that I’m gonna go over to kind of use, and everybody has their personal preference. I like using Teller acuity cards. It’s a preferential looking test. It has a wide range of acuities that can be tested at several different distances. 38 centimeters, 55 centimeters, 84 centimeters. So you can kind of adjust your working distance and still get pretty good measurements. The nice thing is also that you can correlate it to a Snellen equivalent. So it doesn’t necessarily correlate to a Snellen acuity, but at least a Snellen equivalent, to kind of get an idea where that child’s vision it. Because a lot of people, even though they may not understand what exactly 20/40 acuity means, they at least know whether or not it qualifies that child for services. So I included the calculation for this, how it works. It’s essentially — you have your Snellen denominator of your acuity, and you use this equation over here to calculate your cycles per degree, and that’s gonna give you a measurement of Snellen acuity. So if you have your patient — your patient sees 19 cycles per centimeter, you’re gonna plug that into this calculation here. It’s gonna be 20 times 30/19, and it’s gonna give you a Snellen denominator of about 31.6. So that your child’s acuity with that level of vision is gonna be about 20/32. The reason why I included it is I can find this calculation rarely when I need it, so hopefully just having this available to you would help you in the future times that you use this acuity chart. Additionally, there’s Patti Stripes, so it’s kind of the same concept. It’s just a paddle, rather than those large cars. If you ever have held a box of Teller acuity cards, they’re very heavy, so not very portable. These paddles do exactly the same thing, and you essentially can take these with you wherever you go. It doesn’t have the wide range of acuities, but it does typically work well enough to be able to have a few different options for you, and take them kind of with you wherever you go. Cardiff cards are another type of preferential looking card that you can use. They have these shapes that are over here, and they correlate to different levels of acuity. Their range is a little bit narrow. Where it only goes up to about 20/160 down to about 20/12.5. So these are kids that maybe have higher functional vision and maybe not encompass the entire range of acuity that we may see in our clinics. But it’s at least another test that’s available that a lot of people — it’s becoming more popular to use. I haven’t used it very much. But when I have used it, it’s more for the kids that have a higher level of functional vision. But it’s a personal preference, when you start looking at cards. When you’re looking at kids that maybe have higher visual development, there’s distance vision charts. We can use Lea Acuity charts, and just use the shapes. That sometimes is a little bit better for kids that have — they’re a little bit more aware of shapes that are available. HOTV chart — we’re just using four different letters, and kind of cycling all the way through. This is also another great way to kind of present letters at a distance for a child. And then the Feinbloom chart. It’s not everybody’s favorite chart to use. I did my residency at the Feinbloom Center, so I’m a little bit partial. That being said, the nice thing about the Feinbloom chart is it’s only numbers. So some children maybe are more developed with their numbers than they are with letters, when they see you. So that might be a good chart to be able to use for those as well. For near acuity charts, the same types of things as distance, the single optotype, the shapes and the letters, a lot of the distance charts are now mirrored at near. So when you do look at a near acuity chart, it’s good to kind of get an idea of, if you’re using a distance chart, to kind of mirror that at a near distance as well, because you know the child is gonna be successful and they’ve had some practice with it. Some kids have a little bit of difficulty with crowding. So you may have to kind of block or occlude a letter or a line at a time. So feel free to use something like a Post-It Note, use your hands, or even a line guide to isolate a line or a letter, and that may give you some better results as well. The next card that I’ll talk about for near that’s important to look at is a continuous text card. And this is gonna be a card that essentially has sentences. It has some context. And this is — sometimes we kind of overlook this with kids, because as long as we know we can see the letter, they’ll kind of work well with sentences and paragraphs, if we give the same device at home. It’s not always the case. We need to make sure that our children are reading at an appropriate — we’re gonna talk about reading rates in a little bit. The nice thing about this continuous text card is it has sentences that kids can — we can see how their eyes kind of coordinate looking across the page, how quickly they read, and see if we need to make any modifications with the printing. We also have some information about comprehension. So it’s one thing to be able to read the words, but are they comprehending? That’s an important concept. Sometimes we don’t always spend as much time as we should with children. So we need to kind of take a look at that, making sure we’re using a developmentally appropriate chart when we’re looking at continuous text. So when we’re looking at acuity measures, we may have some kids that just don’t have that level of acuity to kind of participate in other care. So we have fixate and follow. Just following a moving target or a transilluminator. Pupillary responses. Do we have light perception at least? And then OKN responses. So using the OKN drum. By turning that drum, we can see if we can elicit an OKN — a nystagmus type of response, to see if that child’s actually able to see that type of print. The important thing is to move that drum slowly. Because if you move it too fast, it’s just gonna blur. And it won’t create the response you’re looking for. With entrance testing, some of the things that we’re gonna take a look at, when we’re looking at alignment, when we’re doing extraocular muscle movements, we also want to look for null points, for kids who have nystagmus. We want to make sure that we’re not going too fast with this, because if you go too quickly, you’re gonna lose some of the visual attention that that child has. So you want to make sure that you’re moving at an appropriate pace. Sometimes if I have a child who’s not really doing well with the light, I’ll kind of have them move their finger in space, and I’ll kind of show them what I want them to do. It gives kind of the benefit of proprioception, kind of knowing where their finger is in space, and being able to follow the target. And usually they’re a little bit less apprehensive. Sometimes I can put a little puppet on the top of it, and that kind of makes it a little bit fun as well, and just kind of verbally directing the gaze in a different direction. We also want to take a look at alignment. We have a strabismus that we’re dealing with. So we want to do a cover test, or maybe Hirschberg assessment. Cover tests — the important thing to realize is whatever near target you’re using or distance target, making sure the child can see that same target in both eyes. Sometimes we use a target that’s too small, and we’re not gonna be able to pick up fixation. So in that situation, we lose the benefit of that alignment assessment. Pupils are an important part to look at as well. The reason why I included this is — you know, we look for the neurologic response, but you also want to see what the pupils do in response to bright light. If you have somebody who has large pupils that don’t respond well, that’s gonna be somebody who has significant glare issues. So some conditions may cause a slowing of the constriction response with pupils, and so it’s important to make sure that if you do see some sort of condition that may create glare, it’s important to address that as well. Also, when we’re looking at modifications for kids that are a little apprehensive when you have that light kind of flashing toward them, kind of just simulate the movement with a puppet, and then that might help with kind of getting them used to something being closer to their face, and then you just add the pen light in on top, or underneath the puppet, and that will help give you some responses. Color vision is incredibly important to look at as well. Some of the modifications for that, when we’re doing the arrangement test, that’s more for somebody who has a very good visual development and cognitive development. So the arrangement test that sometimes we use, the large D15 test plate, might be a little bit of a challenge, but something to kind of consider for kids as well. Color matching and naming — also an important gross assessment of color vision, as well as color plates. I included this one, because Ishihara is one of those — has a great color plate, where you can see if your child can actually follow the shape on the plate. So somebody who’s non-verbal, or maybe a little bit shy, they may not want to tell you what the number is on the other plates, but they can at least find that snake in the grass, or find that worm, and that might be able to get them to kind of participate a little bit more frequently. Side vision assessment — a lot of our kids do not do well with standardized visual field assessments. So it’s a good thing to make sure that you have different ways to assess visual fields. One is just doing confrontation fields as a standard procedure. Kind of using your fingers off to the side, or giving a high five in different fields of gaze. We sometimes use this device — it’s called a vision disc, and it kind of gives you at least a measurement of kind of… Oops! I pressed that button a little bit early. But it gives you an idea of the degrees of measurement that are off to the side. That’s just a gross assessment there. Other ways is that you can have one of your colleagues stand behind the child and bring objects from the side? And depending on how the level of vision — you can use something that’s a little bit bigger, or something that’s a little bit smaller, depending on their visual ability. Also, someone who has cortical vision impairment, their visual development may be a little bit slower, so using something that maybe has a rattle in it, so you have auditory and visual stimulation, we can kind of show both, and try to get that child to kind of look into that other field of gaze. So you can use a lot of different targets when you use this type of methodology. So we’re looking at visual deficits. There’s a lot of issues that we’re seeing with kids that are in, like, a special education setting. And this study awe that Black and their group did kind of looked at different areas of deficits. And we kind of look at the different percentages of things that we’re seeing. Refractive error is the most common that we’re seeing. We’re also seeing reduced contrast, which is something that we don’t always test for in children, in the primary care setting. So it’s good to kind of get an idea that we need to look for this as well. Reduced acuity, anomalous eye movements, saccadic issues or atropia, visual processing, which is also another thing we don’t always test for in a primary care setting, and also that kids present a lot of times with more than one deficit. So it’s not uncommon to see… I mean, it’s not as uncommon as we thought to see a couple different combinations of issues that patients may have. So we move on to refraction. Since we’re all eyecare providers, we know how important refraction is. It’s probably one of the most crucial parts of the assessment. Because we have to get a good assessment of kind of how much glare is related to just uncorrected refractive error. Important things to keep in mind when you’re doing retinoscopy — I suggest using skiascopy bars. This is helpful, because you can stay outside of the phoropter and see what that child is doing. For fixation, you can use things at a distance like a video that you might be able to play, having parents or staff members sit at a distance, and you may also need to adjust your working distance. You may have to — if somebody has really high corneal scarring or significant cataract, you may need to do dynamic ret and get a little bit closer. Don’t be afraid to do damp retinoscopy. It’s important to get a good reflex. In some kids that overaccommodate, you might overminus them or overplus them, so you want to make sure that you do an appropriate retinoscopy assessment, and damp ret will help you kind of at least get a full picture of what that’s going to be. Some conditions present with certain refractive errors that are pretty you common. Albinism — you’re gonna see a lot of with-the-rule astigmatism. The range of myopia/hyperopia may vary, but astigmatism is gonna be common. That’s also the same with anybody that has that pendular nystagmus. So congenital nystagmus, achromatopsia, those kinds of conditions will create a with-the-rule astigmatism. Other things — Down syndrome. We might see moderate to high myopia with our kids. Microphthalmos, because the eye is just so short, we’re gonna see a lot of high hyperopia, and ROP we’re gonna see high myopia. So this is a good table to kind of get at least an idea of maybe — if you haven’t worked with these populations of kids, what to maybe look for when you are doing refractions. It helps kind of guide you, if you start to see something that’s a little bit different. When we get to refraction, we have an idea of their best corrected acuity. We have an idea of goals, and we’re kind of starting to look at the low vision rehabilitation portion at that time. I included this study for a couple of reasons. It’s a small sample of kids. It’s only 22. But the age is a range of 2 to 6, and there are some interesting things that I saw in this study. First off is they were able to obtain appropriate measurements with kids this age with visual acuity, visual field, contrast, and color vision. So we can at least get some sort of assessment of those. Sometimes we will wait ’til you get older, or wait ’til they’re more developed, before we try these things, but it’s important to kind of realize that we can get these measurements on young kids. Additionally, when we’re looking at prescribed devices, about half were prescribed near. A little bit over half were prescribed distance devices. 40% were prescribed both. But the other thing we need to keep in mind is almost 30%, just under 30%, were prescribed pre-device instruction. So these parents got information about what devices are, and the kids got a chance to use them. So even though we weren’t prescribing, they at least got the chance to kind of see what devices would be helpful as that child develops. So we may not be prescribing for those really young kids, but we can at least educate the parent and the child of what’s available when they need it, as they go forward. So with low vision, with kids, there’s a few different strategies that we use, that are pretty common. Relative size magnification, where we just make the object itself bigger, we substitute for a larger print, so this is using just regular sized playing cards, and what we can do is just substitute it for something that has something that’s a little bit larger. So how we use this with children is essentially with using large print books. Rather than the regular small print book that the child may be using — substitute for large print. Additionally, we can use larger monitors. So if the child is using a closed circuit TV, just getting a monitor that’s a little bit larger than their typical screen. Computers and iPads with larger screens as well. Also, when we’re making suggestions back to the teacher, we want to talk about large print tests, making sure homework assignments are enlarged, as well as textbooks, again, being large itself. And then also maybe using a thicker pen, versus a pen or a pencil. Just anything where that object that that child is looking at is larger is gonna be really helpful. Another option that we have for improving magnification and visual ability for kids is using relative distance magnification, just by getting closer to that object. We use it for some of our different strategies, but just moving closer to an object itself makes it a lot bigger, a lot easier to see. So this is a water bottle sitting across the room on a table in my office. And just by getting closer to it, the retinal image size becomes much larger and much easier to see. So some things that we can suggest for children. For kids, bringing their reading material closer, or getting that child to get closer to an item of interest. So getting up to go copy something down from the blackboard, getting up and going to see the clock in the room, to see what time it is. When we’re making recommendations for children, we want to talk about preferential seating, where that child can sit closer in the front of the classroom. Going to an assembly, sitting in the front row of the bleachers, making sure that child has a better seating position, so that we can benefit from relative distance magnification. And we also want to encourage, if the child is holding things closer to see, we want to encourage that. Because a lot of parents are afraid that that’s going to be something that hurts the eyes, but we know with normal accommodation that it helps that child see much better. If need be, we can always prescribe reading glasses to be able to kind of alleviate some of that accommodative demand and make things a little bit more comfortable. So when we’re looking at prescribing, there’s a few things that we need to take a look at, when we’re starting to calculate the devices that we’re gonna be looking at. And we are gonna calculate a couple different types of devices that are just helpful to kind of take a look at. One is you want to make sure that you take into consideration the unique characteristics of a child and their environment. So the classroom that they’re in, the homework that they’re doing, and then hobbies and extracurricular activities. All of those things are gonna be very specific to that child, and those are the things you want to keep in mind, when you’re looking at prescribing. You also need to have an idea of where to start when you’re looking at devices. Because kids lose attention quickly, and so you need to be quick. So when we’re looking at a device like a telescope, it’s important to kind of have an idea of what starting point you’re gonna be looking at. So you can kind of do a quick calculation of what the patient’s seeing, kind of what their goal print is, and create a ratio to see what power they’re gonna need to be able to take a look at. So with the magnification, you look at the patient’s current best corrected acuity, and you divide that by their goal acuity, what they can see, divided by what they want to see, and that’s gonna give you a magnification level for that child to be able to see. Or at least a telescope to kind of start with. So when we’re looking at telescope example here, we have our patient’s best corrected acuity is 20/400, and their goal is 20/50, so we do what we did before. Their best corrected acuity, what they can see, 400, divided by what they want to see, 50, and we’re gonna do our quick calculation that’s gonna get us to 8x. So essentially you’re gonna start your telescope evaluation with an 8x to meet their goal. So I have a poll question where we’re gonna try this out. And we’ll see how this works for you to see what you’re able to calculate with that. So let’s give this a shot. Patient’s best corrected visual acuity is 20/200. You want them to be able to see text on a blackboard, which is equivalent to 20/40. What telescope power would you start with, to meet this goal of seeing 20/40? Perfect! 5x is the correct answer, and just about everybody got it correct, so we are in good shape. So essentially you’re taking that 200 — what they can see — divided by what they want to see, that 40, and that’s gonna give you 5x. So when you’re looking at the types of telescopes that are available, it’s going to be dictated by your child’s goals and what they want to be able to see. I do a lot of handheld devices with kids. Just that they can wear as a lanyard around their neck, and just kind of have it available, kind of as they need to. Binocular — sometimes we’ll kind of prescribe binocular devices for kids, even just using a pair of binoculars that you might get at a sporting goods store is also helpful as well, because it helps keep everything nice and steady, as they’re gonna through. You can custom design a telescope, but usually I like to see how a child responds to the distance magnification first, before going down that road of a prescription device. Oops, sorry. For near assessments, we’re looking at prescribing a near device, we kind of do another quick calculation as well. And essentially we’re using that same type of ratio, what they can see, divided by what they want to see. And you times that by the inverse of their working distance, what they came in seeing. This gives you an equivalent power that’s gonna help them be able to meet their goals of the print that they want to be able to see. So, for instance, you have a 6-year-old who reads 0.4/4M with normal accommodation. He wants to see a comic book print equivalent to 1M. So he can see 4M. He wants to see 1M. You times that by the inverse of that working distance. So 1/0.4 is gonna be 2.5. And that’s gonna give you 10 diopters. So essentially, a 10 diopter equivalent, whatever device that you should happen to use, should get that patient to be able to meet their goal of 1M. So it’s an important kind of quick calculation to be able to do. The telescope in this one are the two primary ones that I use. And then I spend most of the time kind of working with the different devices. Devices available for a kid — there’s a lot that’s out there that we may use. But these are kind of the basic ones that I typically use. Stand magnifiers and dome magnifiers are great, because they just line up on the print. We don’t have to worry about dexterity of a handheld device. Kids that have contrast issues — we could always show them an electronic device, to kind of help out with enhancement of contrast. There’s a lot of options that are available, that may be helpful for your kids. I’m gonna skip over this example, and I’m gonna go straight to this one. So with estimation of print size, a lot of kids are gonna come in things like homework, or maybe a book that they need to read, and that’s gonna be their goal, but it may not match up perfectly with a near card that has a specific acuity notation, like 20/40 or metric notation. So what we can do is we can at least estimate the print size by doing a simple quick calculation. So what we would do is we would look at kind of what our normal metric letter size is, which is typically 1.45, and we use that kind of as a scale to measure what metric notation acuity size our patient needs to see. So we’d measure the height of the letter. We divide that by 1.45, and that’s gonna give us our estimated M notation size. So this example here — what we’re gonna look at is that letter D that’s up on the top. Just gonna zoom in a little bit for you. And we measure from the top to the bottom of that letter D. It’s gonna be about 6 millimeters. So if you divide that by 1.45, it’s gonna give us an equivalent of 4.1M notation, and then that would become our goal, when we’re calculating our near acuity — our near equivalent power devices. So that’s essentially how I would use kind of a simple thing like a ruler, converting it into metric notation, to use it as a goal print calculation. So we’ll do a quick poll question here, kind of measuring that exact same thing. A child is having difficulty reading text in a book. It’s not available in large print or via a tablet. Since this is the goal print, you want to determine the appropriate optotype size to ensure your equivalent power calculations will be accurate. You measure the print size to be 4.35 millimeters in size. What’s the closest M acuity size of this print? 1M, 2M, 3M, or 4M? Okay. So we have a couple — a bit of a range of answers on this one. What we’re gonna do is we’re gonna look at this 4.35 letter size, and then we’re gonna divide that by our 1.45, and that’s gonna give us a 3M size calculation. So that becomes, then, our size calculation for our equivalent power. So my email is at the end of the presentation. If you have any more questions about that, feel free to email me about it. We’re gonna move on to the next thing, but please of course let me know if you have any other issues with that calculation. Uh-oh. Oh, here we go. Okay. So when we’re talking about reading for children, kids, as they go through development, are gonna be reading more and more and more. And so a lot of times, children will compensate for decreased vision by using relative distance magnification, by bringing things closer, and that helps resolve the visual detail. The challenge is that when we do that, there’s no task lighting. There’s no contrast enhancement. Postural problems. Kids kind of hunch over, and their shoulders get sore, and just the cosmesis. It looks different. So that’s why a lot of times we do need to look at some sort of assistive device, like a magnifier, or other type of approach to help kids be able to see up close. There’s a couple of studies that I’ve looked through, and looking through a few different pieces of information that were interesting was that kids with low vision can approach reading rates of normally sighted children with appropriate magnification. So using the appropriate power and appropriate type of device, they can get to be reading almost as quickly as normally sighted children. And in another study, Corn et al. found that using magnification devices or assistive devices have a tendency to improve their reading rates over time, where kids that only use large print have a tendency to plateau. That’s important to realize, because not every book is gonna be available in large print, or not every resource will be available in large print. So it’s important to make sure that as we’re kind of going forward, we’re introducing devices so kids can keep up with their reading rates that they need to, to keep up with their classroom work. With children with reading rates, in kids — reading rates will improve as kids get older. Reading rates typically increase about 10 words per year in visually impaired, and about 14 words per minute in normally sighted. So there is a little bit of a gap, but it’s not very significant. Per year. Cumulatively over time it is pretty significant. So it’s one of those things we want to keep in mind when we’re looking at assessing devices. With a lot of classroom activities, depending on what age that child is, and what year they’re in, in school, different reading rates are gonna be more appropriate. For a younger kid in third grade, 60 words per minute might be okay. But as we get older, that reading rate may not be appropriate, given the volume of reading. So it’s important to kind of make sure that as you kind of are assessing children from year to year, you’re listening for reading rate, so that you can at least get an idea — are they gonna be able to keep up with the volume of work that they’re gonna be able to do? Kind of as they’re going forward. Other options that you have for children are smartphones and tablets. Kids are a lot quicker to pick up technology. So it’s one of those things that is kind of inherent, as their normal development. Kids typically learn by trial and error. So they’re very quick, and they’re very apt to pick things up with technology. Additionally, when we’re looking at smartphones and tablets, there’s a lot of opportunities to enhance the vision. One is contrast enhancement. Large print. Also, it’s a lot cheaper to kind of use one device that can do multiple things. So if you have a smartphone that can be a telescope, use it for reading, it’s gonna reduce the cost and make things a lot easier for parents and school districts that may be providing these devices. Lastly, it also keeps up with the concept of inclusivity, where everybody has that possibility of kind of being included in an activity, because they all have the same device. So it’s one of those things that we’re looking at smartphones and tablets are becoming much more the forefront of available devices. Some things to keep in mind also. A lot of kids — they’re not gonna maybe complain about it, but they’re gonna have issues with glare. So it’s important to look at glare control, as well as UV protection. Other things to look at too are tints, and kind of making sure you’re using filters to kind of block out some additional light. Disability glare is additional glare that reduces visual quality. And we want to reduce disability glare as much as possible, so just using something like a yellow filter for indoors, a gray filter for outdoors, may be helpful. A wrap frame might be helpful, or a fitover. Depends kind of on your child. Other things here are tinted contact lenses. This is me. This clearly isn’t a child. Clearly not a child. But if you look over here, I’m wearing a tinted contact lens. It’s just a dark blue, and it helps just take a lot of the extra glare in the room. Cosmetically, it is a little bit different, but it was actually pretty visually comfortable, after I wore it for a little bit. And it wasn’t as uncomfortable to wear as I thought it might be, given the history of tinted contact lenses in the past. When we’re looking at our rehabilitation team, we want to make sure that we’re kind of keeping everybody on board, when we’re working with children. So making sure that we’re communicating, making sure that child has orientation and mobility training as needed, as they go through school, having access to a vision teacher who can help coordinate services in the classroom, social work and school psychology are very important with the mental health, as well as the development of the education plan that child may need. And we also want to make sure that we’re communicating with the managing eyecare physician and primary care physician. Make sure that any medical needs are being addressed, and anything that kind of stands out, that might be different, are also being addressed as well. So when we work with a child, there’s always gonna be a team that’s involved, to make sure that we’re taking care of that as well. I added a couple slides about having vision clinics in schools. Sometimes it’s hard for children to come to us, so it’s sometimes appropriate to develop clinics in schools. And it’s something that I did when I lived in Chicago. We’d go to classrooms and be able to see how children interacted, be able to prescribe devices in that natural environment. It’s also a great way that you would have that access to the vision teachers and O and M specialists. So it’s a different clinic than maybe what you might typically do, but it’s a great way to kind of get to that child, and be able to assess them in their normal environment. That’s very important. Rather than kind of in your clinic, which might give you a little bit different results. There was a study that looked at prescribing devices and wearing glasses, and kind of the outcomes of that. A few months after the clinic, what the surveyors found is that not everybody was wearing their glasses. Not everybody was wearing the prescription that they had been prescribed, and some of them had very significant prescriptions. Teachers, though, had a very positive feedback. They thought there was a change in children’s engagement, but in some kids, the behaviors were not significantly changed. Kids were not visually engaged with tasks, or they kind of stayed off-task. So this may be one of those things that maybe the follow-up was too soon after, or maybe it was too far away, that there wasn’t as much intervention kind of going forward as they had hoped. One other thing that we want to take a look at is report writing. You want to do a summary and make sure that you’re communicating to everyone that when you’re working with a child — to make sure that anybody who needs to know the results of your examination have access to it. Also consider, when you’re writing that report, make sure you know who’s reading it, or at least consider it, as you’re writing that report. A lot of things that we do, we translate our findings. So when we talk about a child being 20/200, that’s helpful. But what can be much more helpful to somebody who doesn’t know what 20/200 means — it’s actually measuring the size of that 20/200 letter, or better yet, even making a copy of that, and sending a copy with the report. So that teacher or the vision teacher, whoever is working with that child, can see exactly the size of the letter that child can see, and then let them know what distance. It’s helpful to talk about contrast loss, implications of contrast loss, because a lot of people don’t understand contrast sensitivity. So mobility issues, facial recognition, it’s important to translate what that means. And then prognosis as well as the recommendations that you might have for that child. And whenever you’re going through your terminology, make sure you’re addressing appropriate terminology for the reader. Consider what you might report back to a doctor, versus a parent. So it’s gonna change kind of the scope and also the terminology that you write as well. So I wanted to find of finish up with a few things. Parents and guardians. You need to keep them involved and active in their child’s rehabilitation and their care. So it’s good to kind of get an idea of what do they know about their children’s eyecare and the care that they’re getting. So there was a study that kind of used a very specific questionnaire, just looking at eyecare, and some of the results were kind of a little bit staggering. So where are parents getting their information about their children’s vision and their health? Not quite 70% are reporting that they’re getting their information from their eyecare providers. Other areas that they’re getting are the internet, family and friends, television. But it’s not even 70% — it’s just not even 70% that people are getting information from us, the eyecare providers. That’s an important thing to keep in mind, as we’re doing our education. Impacts on the quality of health literacy are if the parent’s first language is not the language they’re being educated in. That might have an impact. Education level, high school or lower. And I was kind of surprised — income didn’t necessarily surprise me very much, but $70,000 was the benchmark. I thought that was actually pretty high. But $70,000 was found to be kind of that level where health literacy may drop off. When we’re talking about health literacy with patients, parents, and their guardians, we want to make sure they’re included in their rehabilitation care, we want to make sure they know the resources that are available, and how they can help their child at home, and the carryover from home. So sometimes I’ll use something like a vision simulator, to kind of mimic what the child’s impairment is, or kind of — somebody who’s a 10 diopter myope, I’ll give the parents +10 to hold over their glasses, and see what their child is experiencing. Anything to kind of get them — to put them in the vision of their children, so they understand the impact of what we’re doing. It’s always important to talk about what resources are available, even if they’re not maybe necessary at the time you see the child. They may be necessary going forward. And then one last thing about health literacy of parents. One of the issues that we do see, that sometimes when we’re asking parents why they maybe don’t understand, or maybe some issues they may report, is that medical terminology may not be translated. So maybe not understanding the medical terms that we’re using. And sometimes when we get to a situation where we have a lot of patients, we’re moving a little bit quicker, sometimes we forget to translate. Sometimes parents are embarrassed to ask questions. I think we’ve all been in this situation too. We’re embarrassed to raise our hands and say we don’t know something. So we want to make sure that we do provide an environment where parents feel comfortable. Poor recall of relayed information, just forgetting what they’ve been told, and then receiving information verbally versus taking home information. When they received information verbally, 40% of patients — parents. I said patients. It should be parents. Forgot or misunderstood the information from the eyecare provider. So that’s a pretty significant percentage of information that we’re providing that maybe isn’t being digested and kind of reviewed, after we leave. So we feel like sometimes maybe we’re giving a lot of information, but maybe we need to look at different formats, to make sure our parents are involved in that part of the counseling portion. And I think that’s it. I think I ran a little bit over, but I’m happy to answer any questions, if any questions are available.

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November 14, 2019

Last Updated: October 31, 2022

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