Lazy Eye, Strabismus, Amblyopia – PediaCast 231
Join us in the studio as Dr David Rogers and Dr Mike Patrick discuss strabismus and amblyopia. Also known as lazy eye, these conditions are a common concern for parents and the leading vision-robbing disease of childhood. Hear the details and get your questions answered… this week on PediaCast!
- Lazy Eye
Announcer 1: This is PediaCast.
Announcer 2: Welcome to PediaCast, a pediatric podcast for parents. And now, direct from the campus of Nationwide Children’s, here is your host, Dr. Mike!
Dr. Mike Patrick: Hello, everyone and welcome once again to PediaCast, a pediatric podcast for moms and dads. This is Dr. Mike coming to you from the campus of Nationwide Children’s Hospital. It’s PediaCast 231, 2-3-1, for October 31st 2012. So Happy Halloween to everyone out there. We’re calling this one Lazy Eye, Strabismus and Amblyopia.
So I do want to welcome you to the show. This week we are covering another condition that many of you out there will find familiar and that’s because literally millions of Americans and of course millions more around the world are affected. We’re going to define lazy eye for you and tell you why it’s important to identify children who have it and to intervene to possibly prevent blindness.
But before we dissect that topic in detail, I have a few quick housekeeping items for you. As I’ve been mentioning, PediaCast is now on Pinterest and we are providing content there that you won’t find in the podcast. So be sure to head over to pinterest.com\pediacast. You’re going to find two boards over there at this point. Our Episodes board and please repin and share your favorite episodes to help spread the word about the program.
And then this is the one I’m really excited about, we do have a News Parents Can Use board and that one we have links to articles and topics that you might find helpful and these are only on the Pinterest board. So these are topics that we do not cover in the podcast.
And just to give you an example of some of the things we have over there, kids with autism are more likely to wander off compared to other kids. Also another reason to get tonsils and adenoids out for kids with obstructive sleep apnea and this reason has to do with bed wetting.
Irritable babies and the relationship with mental health issue as they grow to teenagers. Also background TV exposure, children are exposed to it for many hours each day. When they aren’t necessarily watching TV but the TV is on in the background, what effect does that have? And also teenage cell phone use, especially after bedtime. What are the consequences of that?
So these stories and many more on the PediaCast News Parents Can Use board that’s over on Pinterest. So be sure to check that out and please follow us there and repin and share the stories that you like and think would be helpful for others moms and dads.
Also Nationwide Children’s has developed a resource guide to help you out. It includes answers to frequently asked questions, not only about seizures and treatment of epilepsy, but also helpful hints and safety tips. You might wonder should a child with epilepsy play sports; should a teenager with a seizure disorder drive. Our experts pooled these questions and many more into a go-to-guide that you don’t want to miss. It’s free and it’s for you. You can easily find that by checking out the Show Notes for this episode, 231, at pediacast.org.
And then one more item for you and you’re going to love this because it’ll bring us around, albeit in a very circuitous fashion to today’s show. A few episodes back, I covered infantile hemangiomas and I did not get a pediatric dermatologist to join me for that discussion. Instead, I forged to head on my own, which I often do when we answer listener questions.
So I didn’t ask a dermatologist, but a dermatology resident did write in with some comments about our hemangioma discussion and I do want to share those with you while hemangiomas are still relatively fresh on everyone’s mind.
Dr. Sarah in Rockville, Maryland says, “Hi, Dr. Mike. I’ve been a long time listener since my pediatric’s clerkship in medical school. I continue to listen for the newest in pediatrics as I have two young boys of my own. In a recent show, you discussed infantile hemangiomas. I was a little disappointed for a few reasons. I’m a dermatology resident now and I see these fairly frequently. First off, I don’t think you can underestimate the impact that hemangioma has on parents and young children even if it is considered just cosmetic. From parents having to deal with questions about what happen to their baby to being singled out by other toddlers and young children, the impact can be quite marked. In addition, you made a statement to the effect that most hemangiomas will resolve while they do involute they tend to do so with remaining fibro-fatty tissue, which can impede function and again can be cosmetically concerning as well as inhibiting function. Another area where I felt your discussion was lacking was treatment. New treatment options exist in the form of oral and topical beta blockers. There are numerous papers on the subject. I included links to two below. I wouldn’t go so far as to say that all hemangiomas need to be treated but I felt the show swayed toward the other end of the spectrum and that it discouraged parents from treating unless the lesion is ulcerating or impairing function. There are other options now and it’s worth talking to a dermatologist experienced in these treatments before making decision on a case-by-case basis. Beta blockers are changing the way we deal with hemangiomas by providing a safe and effective alternative and allowing to treat prior to the onset of the proliferative stage. Keep up the great work. I love your show and use it as a way to stay connected with pediatrics and keeping up with information important to my family. Thanks, Dr. Sarah.”
Well thank you, Sarah, for chiming in. Of course, we want to give the very best and up to date information into the hands of moms and dads and I’ll include the links Dr. Sarah sent to me in the Show Notes over at pediacast.org, so you can check them out for yourself.
They include a link to medication update for infantile hemangioma. Also topic Timolol for treatment of infantile hemangioma and Propranolol vs. Pregnozone in the treatment of infantile hemangioma. If you’re interested in PubMed links to those articles, again you can find them in the Show Notes.
All right. So how am I going tie in Dr. Sarah’s comments with today’s show? Well check this out. Back in 2006, in the course of PediaCast no. 2, that’s right, our second show, I covered lazy eye, strabismus and amblyopia.
In fact, that’s the last time we covered it. So I figured it was time for an update and this time I did bring an eye expert into the studio with me. But during that show in episode 2, I made a comment about the importance of seeing a pediatric ophthalmologist rather than an optometrist if your child has a lazy eye and of course that set me up for my very first complaint email right after episode 2 (It was a great start, I know), because an optometrist just happened to be one of my earliest listeners and she was quick to let me know that optometrists are perfectly capable of seeing kids with lazy eye and should be trusted to make a referral to a pediatric ophthalmologist should it become necessary.
So there you have it, hemangiomas aren’t my only corrected topic, lazy eye is another one from the early days of the show. And by the ways, I don’t mind being corrected. We want to get the best information in the hands and ears of our listeners, so that’s fine. And of course, sometimes experts have different opinions and they’re certainly in many cases more than one way to approach a specific medical issue.
Speaking of medical issues, let’s get back on track and talk about lazy eye, strabismus and amblyopia. We do have an expert in the studio as I mentioned. Dr. David Rogers, MD, is a Pediatric Ophthalmologist at Nationwide Children’s Hospital. We’re going to introduce you to him right after I remind you that if there’s a topic that you want us to talk about it’s easy to get a hold of me, just go over to pediacast.org, click on the Contact link. You can also email email@example.com or call the voice line at 347-404-KIDS. That’s 347-404-K-I-D-S.
Also, I want to remind you the information presented in every episode of PediaCast is for general educational purposes only. We do not diagnose medical conditions or formulate treatment plans for specific individuals. So if you do have a concern about your child’s health, be sure you call your doctor and arrange a face-to-face interview and hands-on physical examination.
All right. Dr. David Rogers, MD, is a Pediatric Ophthalmologist at Nationwide Children’s Hospital and an Assistant Professor of Pediatric Ophthalmology at the Ohio State University College of Medicine. Dr. Rogers attended medical school at Wright State University and completed his residency and fellowship at Indiana University School of Medicine. His clinical interests include pediatric and adult strabismus, pediatric cataract, glaucoma and low vision.
He’s also a clinical researcher in the areas of telemedicine for retinopathy of prematurity (ROP), pediatric vision screening, pediatric cataract and outcomes in strabismus surgery. He joins us today to talk more about strabismus, one with lazy eye and amblyopia.
So let’s extend a warm PediaCast welcome to Dr. Rogers. Thanks for joining us.
Dr. David Rogers: Well thank you, Dr. Mike. I appreciate the opportunity.
Dr. Mike Patrick: It’s great having you here. Let’s just start with some definitions because we’re throwing lazy eye I guess isn’t an easy enough term, but amblyopia and strabismus these are all kind of big terms. Why don’t we start with strabismus? What exactly is strabismus?
Dr. David Rogers: Well, a strasbismus is a misalignment of the eyes and that’s a basic definition. You might refer to strasbismus or make an analogy of this definition by saying what is vegetable. And if you ask somebody what a vegetable is or to define it, they might tell you many different things. But strabismus is simply a misalignment of the eyes just like there are many types of vegetables, there are many kinds of strabismus.
And the most common types are eyes that drift in towards the nose, that’s called esotropia. There’s the type that drifts apart or away from the nose, that’s called exotropia. And then other types are noted those that drift up or even down. Then we can have oblique misalignments of the eyes.
Dr. Mike Patrick: We were talking about misalignments, so we’re talking about one eye compared to the other when we say one’s kind of drifting in or one’s drifting out or up and down or in an angle.
Dr. David Rogers: That’s exactly right. But an important note to make here is that when we look at something we always do that with at least one eye. If you’re going to look at something you have to align at least one eye with whatever object that you’re identifying.
If you do have misalignment of your eyes, a strabismus problem, then one of your eyes may be drifting. Now, just like we have a dominant hand, we will always pick our dominant eye to look at something with. If you would cover somebody’s dominant eye and force them to use their drifting eye, they will then move that eye into alignment with the object that they are now looking at. And if you could look behind the covered eye you will see that it is now drifting.
And so strabismus is a misalignment of the eyes. It really affects binocular alignment of the eyes. We only noted in one eye at times and we say that it’s mainly my right or my left eye that’s drifting, but in actuality, the eyes are yoked together, they work together and we may have a preferred eye and we may just let the opposite eye drift, but in can really affect both eyes.
Dr. Mike Patrick: Gotcha! And then what is meant by the term amblyopia? It’s a big word.
Dr. David Rogers: Sure. Amblyopia is simply poor vision in one eye. Now it’s very, very important to understand that amblyopia is not an inherent disease or process or pathology or problem with the eye, itself. It’s really a neurodevelopmental problem in the brain.
Dr. Mike Patrick: Now, when we say lazy eye, so the term lazy eye, there’s really a lot of different things that parents kind of use that term for that sort of encompasses both strabismus and amblyopia. What’s really the correct way to use the term lazy eye?
Dr. David Rogers: Well as you noted, lazy eye is an ambiguous term. It typically refers to three different conditions and the two most common would be strabismus and the amblyopia. And then some parents refer to a droopy eyelid or ptosis as being a lazy eye.
I think that in the medical world we don’t use that term at all. Parents and lay people are free to use the term and I think it’s pretty well understood by most people that it could mean either a poorly seeing eye or a misaligned eye. But in medicine we don’t use the term and we avoid it.
Dr. Mike Patrick: Right. Now, why are we talking about strabismus and amblyopia together? What’s the relationship between the two of those things?
Dr. David Rogers: Well that’s a great question. And the key is that they most often times show up together. Now, you can simply have an eye that doesn’t see well and is perfectly aligned and that can happen when you have a difference in the eye’s ability to focus correctly known as anisometropic amblyopia. But more often than not, when an eye drift or is strabismic, it not only drifts but it also is lazy or has amblyopia. So there are factors that contribute to causing both problems.
Dr. Mike Patrick: Sure. How common is this condition?
Dr. David Rogers: The condition is fairly common. It depends on different reports that you look at but it has been reported to be anywhere to affect 1% to 5% of our population. But I think most people would say it’s closer to 4% or 5%.
Dr. Mike Patrick: Do you see it more in certain ethnic groups or races?
Dr. David Rogers: This is really an equal opportunity disease. We don’t necessarily see it more in one racial or ethnic group or even socio-economic groups. It tends to affect just about everybody.
Dr. Mike Patrick: And what about males versus females?
Dr. David Rogers: That’s also fairly similar.
Dr. Mike Patrick: Pretty equal. Let’s actually start with strabismus, so this misalignment of the eyes, what causes that?
Dr. David Rogers: Well, there are many, many things that cause it. We don’t actually know or have a clear definition of the pathophysiology behind it, but we do know that the brain controls the eye movements. There are centers within the brain that need to be active very, very early in life and there’s a critical period there. And most people would tell you that that critical period is certainly within the first few months of life and probably can extend, in some cases, up to about six months of life. But in that period of time many of us who’ve had children we’ve looked at them and we’ve seen that their eyes may drift out at times, they may even drift in at times.
But usually by six months of age these issues have been resolved. So we typically tell our residents and teach parents that if the eyes continue to drift inward after about two months of age and outward after four months of age, this is something to be concerned about. And we would like to see all of those children before six months of age.
Dr. Mike Patrick: Sure. Are there any particular risk factors where you might see strabismus with other conditions?
Dr. David Rogers: Well, inherent risk factors would be abnormal refractive errors. Refractive errors such as high hyperopia. It’s probably the biggest risk factor for developing strabismus. Hyperopia describes an eye that’s fairly small and it requires a plus lens to focus light to the back. And typically, most children are a hyperopic or far sighted. But when that refractive error is extreme, typically over about four diopters or four lens powers, we will see strabismus or misalignment of the eyes.
Dr. Mike Patrick: Sure.
Dr. David Rogers: That’s the biggest risk factor. Now other risk factors would be disease processes inherently found in the eye that could cause the eye to drift if they cause the vision to be poor in the eye.
Dr. Mike Patrick: What about if a kid has other neurodevelopmental problems like cerebral palsy or Down syndrome, hydrocephalus, do you see it more often in those kinds of kids who have other CNS issues or is it not related to those things really at all?
Dr. David Rogers: I think it is related. We have good evidence that these conditions have a higher association with strabismus and ocular misalignment than other healthier children. It’s also quite commonly seen in chromosomal abnormalities at all times.
Dr. Mike Patrick: Sure. Now this maybe oversimplifying this a little bit, but the way that I understood the relationship between strabismus and amblyopia is that if brain is not getting a clear picture, it wants to get a clear picture and so it starts to ignore one eye and then you can lose vision in that eye in order to maintain. Am I close or is that not the way this is thought of anymore?
Dr. David Rogers: No. I think we still think of it that way and you’re very close. Let me just clarify a few points. Vision is clearly a learned process and it’s just like any other learned task that we have in life. Nobody is born and knows how to get up and walk around. Our bodies need to develop and muscles and bones need to develop enough strength and structural integrity for a child to get up. And centers in the brain also need to be useful in working together for coordination and balance.
Well vision is very similar. So children are actually born blind. They’ve never seen light before. Now the eyes are fully able to focus and the retinas are developed enough to actually see and send a focused image back to the brain. But if that process is at all disrupted in any way, either with one eye or even both eyes, then the centers of the brain that should be receiving that signal do not develop correctly. And that is the root of the problem in amblyopia.
Dr. Mike Patrick: Now, strabismus or misalignment would be one reason that that would happen, but anything really that interrupts the flow of vision in one eye then could result in amblyopia.
Dr. David Rogers: Well absolutely. That could include a droopy eyelid that covered light from entering the pupil. It might also be caused by a scar on the cornea, the front surface of the eye. It could be caused by a cataract in the eye that would cloud the lens. It has been documented in vitreous hemorrhages, hemorrhages that can occur inside the eye, and it can even result from problems affecting the optic nerve.
Dr. Mike Patrick: And just to kind of bring it back around to our introduction, if you had an infantile hemangioma near one eye then that could do it as well.
Dr. David Rogers: Absolutely. Many times that’s because the hemangioma may be causing mechanical force that causes a droopy eyelid or covers or blocks the visual access or even causes pressure on the eye that distorts the vision.
Dr. Mike Patrick: Now you talked about what parents should look for in their young baby if they have an eye that looks like it’s drifting, especially if they’re younger than about six months old or so, that they really ought to be seen by a pediatric ophthalmologist. You know, my optometry friends may complain about me saying that but I’m still going to stick with it. As kids get older, I suppose that some subtle forms of strabismus may be missed. What other kinds of signs and symptoms would you expect in a kid who has this?
Dr. David Rogers: Well, you’re absolutely right. There is a term known as microstrabismus and this will describe misalignment of the eyes that’s too tiny or too small for the average person to identify. And it really takes a comprehensive eye exam to discover or bring it out. And some of the things that you would look for are really subtle and may not be identified or even recognized by parents.
The fact is that most children with a lazy eye don’t know that they have it and they don’t complain. It’s the way they were born. They expect everybody has one eye that doesn’t see as well as the other and they don’t raise their hand and say I have a problem.
Unless the eye is actually misaligning, many of these kids are only picked up through the screening process. And we have great pediatricians out there who would do basic vision screenings at all their well-child visits and they are good at identifying these children and referring them appropriately when needed.
Dr. Mike Patrick: What is pseudostrabismus?
Dr. David Rogers: Oh, pseudostrabismus, that’s a great one and it’s a common thing that we see in the office but this is really a pseudo misalignment of the eyes. Now, pseudo means not real and strabismus as we stated means misalignment of the eyes. And probably the most common type of pseudostrabismus is pseudoesotropia. This is caused by the illusion that’s created that the eyes are crossing in when a child either has a very flat nasal bridge or has medial canthal folds or excessive skin at the inside corners of both eyes.
So if you’re looking straight ahead you should be able to see a little bit of white or the sclera nasally on both eyes. When you look subtly to the left or the right most people will still have white visible when their eyes are turning in towards their nose.
But in these children when they look to the left, their right eyes turning towards the nose and it gets hidden behind the skin or the what fold of extra tissue there and the white disappears. And this causes an uncanny sensation in people that the eyes are misaligning.
If you’re concerned about that, you certainly should bring it up with your pediatrician and see an eye doctor and they can determine if it’s real strabismus or pseudostrabismus. Sometimes they do happen together.
Dr. Mike Patrick: So how do you go about diagnosing this condition?
Dr. David Rogers: Well, strabismus and amblyopia are actually diagnosed through a comprehensive eye exam. And any eye exam would be able to test for both conditions. But the strict medical definition for the diagnosis of amblyopia is typically an imbalance of vision in the two eyes that is more or greater in magnitude than two lines.
So more than two lines of vision difference between the two eyes. And that should be associated with an amblyogenic risk factor. Risk factors such as poor refractive error or strabismus, for example.
And then strabismus is identified by doing a special test called cover testing. There are various techniques that you can use to elucidate strabismus but we do this in the office checking the motility or alignment of the eyes through a motility examination.
Dr. Mike Patrick: So the way that this comes up from a parent’s point of view, either they are going to notice that there’s something wrong with their kid’s vision or something just sparks off that mom radar that something’s not right with their vision. Or they’re going to see that what appears to them to be a misalignment of the eyes, which may or may not be a real misalignment and then they’re going to bring that up with their pediatrician. Or their pediatrician is going to notice it in the course of an exam and that’s both sort of looking at the eyes and examining them and then also doing vision screening in kids, like an eye chart.
Dr. David Rogers: Yeah. Those vision screenings are actually mandatory in schools and they’re typically done in kindergarten, first, third and fifth grades.
Dr. Mike Patrick: Sure. Is there a way to check kid’s vision before they can read an eye chart?
Dr. David Rogers: Well, yeah. Typically, we’d say the standard of care is having your vision checked, each eye individually, using a Snellen eye chart. But there are different symbols that can be used and even picture symbols that can be used in children that are too young to read or even know the alphabet. And if they can identify pictures or play a matching game we can do that and typically can achieve linear acuity, meaning being able to read either pictures or matching letters and objects in children who are three years in age and up. We don’t always get to do that but usually three or four years of age we can get a pretty good idea and a sign in number value to vision.
Dr. Mike Patrick: And even in kids younger than that who let’s say they maybe have other neurological problems and they’re not able to be interactive or they’re younger than three years old, is there a way to test their vision without necessarily them having to be a responsive part?
Dr. David Rogers: Yeah. Now getting the responses is always the best way. So the best way for me to tell you what your vision is would be is to have you tell me by reading the letter chart. But there are children that are too young and those that are developmentally affected by various conditions who don’t always have the ability to give the information we need.
In these children we have other ways and we can use fixation preference. As I mentioned, all of us have a dominant eye just like we have a dominant hand. And when they’re going to look at something we use that one eye, so that can help us identify ocular misalignments or strabismus.
And we can identify the better seeing eye versus the amblyopic or affected eye simply by seeing which eye they tend to choose. We’ll always choose our better eye.
Dr. Mike Patrick: Right. If you examine the eye and you’re looking through and you see the back of the retina and that lets you know that light is getting in. Do you also have a way to tell like if a baby is near sighted or far sighted without them…
Dr. David Rogers: Without them knowing.
Dr. Mike Patrick: Right.
Dr. David Rogers: Well, yeah. If we’re not going to use fixation preference or there are tests for a fixation preference, a teller acuity testing and things like that are tests we use. But if we just want to know what their refractive error is I can tell just by dilating the eye and looking inside using lenses and retinoscopy as the process that we use, we can measure somebody for glasses even if they’re preverbal and I can do that in a one-day old.
Dr. Mike Patrick: Yeah. That’s fascinating. So let’s say that you do diagnose strabismus and perhaps amblyopia associated with it, how do you go about treating that?
Dr. David Rogers: The treatment is pretty systematic. There’s a systematic way of approaching it and we do it very similarly in every patient. First of all, if there was anything that was obstructing vision, the hemangioma, the droopy eyelid that we talked about or cataracts or hemorrhage inside the eye, those things need to be addressed.
First, light has to be able to get in the eye and be it focused on the retina. So if the light can’t get in we have to clear that up. The next step is getting that light in focus. So if you don’t have any of those problems, the next step is prescribing glasses if they’re needed. And we have prescribing guidelines and not every refractive error does require glasses, but those that are causing amblyopia and if your child does have amblyopia we do a trial of glasses first.
It’s interesting that many studies have been done recently and the results are all very similar. And they document that glasses alone are an excellent first treatment and sometimes these children who wear glasses can avoid other treatment options.
Now, after glasses we will try to do penalization therapy and that can be done by occluding an eye with a patch. It can be done by pharmacologic mechanisms, by defocusing the eye using atropine eye drops, then there are people that have patched with various devices like cloth patches over glasses. They’ve even used occlusive tape and then different filters that will just partially obscure the light entering into the eye.
But all of these treatments are designed at forcing the brain to not ignore and use the weaker eye.
Dr. Mike Patrick: So it’s the dominant eye that you’re patching or disrupting the vision in.
Dr. David Rogers: Yes. Exactly. You always patch what we call the ‘sound eye’ and force the brain to use the affected eye.
Dr. Mike Patrick: What about eye exercises? Can you fix this by exercising the eyes?
Dr. David Rogers: Well, eye exercises are interesting. Many people refer to eye exercises as vision therapy. Vision therapy is clearly defined as any therapy that would help vision. So when you give somebody glasses, for example, you’re prescribing vision therapy. When you give them a patch or use eye drops to improve their vision, you are prescribing vision therapy.
There are people that refer to vision therapy as eye exercises and forget that these other treatments are also vision therapy. They specifically asked about eye exercises to try to improve vision. There are no eye exercises that we’re aware of that strengthen your brain the way that it needs to in this case. But there are certainly activities that you can do while you’re patching that will help improve you vision.
So let me just give you an analogy. If you’re trying to lose weight and you want to go sign up at a gym, you can go to the gym for two hours a day and sit there and watch other people work out and have absolutely no benefit at all. But you went to the gym.
Now the very similar analogy can be used in patching the eye. I can patch your eye and you can go to sleep or you can just sit there and daydream. But if you patch your eye and get engaged in neuro activities, neuro-visual activities, then you’re actually forcing your eye to be used for or exercising it. And that has been documented and shown to improve patch therapy. So those that patched and actually get engaged in neuro activities have a much better and faster outcome than those that do not.
Dr. Mike Patrick: Now, I would assume that with all of these interventions that we’re talking about that the earlier you get that started the better since we’re talking about the developmental process and we want the brain to keep recognizing the eye.
What about kids who gets diagnosed later? Is it ever too late to treat this?
Dr. David Rogers: Well I think you’re referring to what I mentioned to earlier as the critical periods. There is certainly a profound benefit to diagnosing this early in life or at least identifying the risk factors and mitigating those factors. But the critical periods that we refer to most generally will include an age range up to about eight to ten years of life.
And historically, we used to think that after that time frame if you hadn’t had any treatment or if you hadn’t had an improvement we would stop treatment or maybe not even offer treatment. But recent studies have shown that children up into their teens and even adults can have some improvement in their vision. This improvement may not be dramatic but some studies have shown one, two and even three lines of vision improvement, which may be quite beneficial to the person
Dr. Mike Patrick: Sure. What about surgical treatment for strabismus?
Dr. David Rogers: Well surgical treatment for strabismus sometimes is quite necessary, but we typically try to treat the amblyopia before we engage in any surgery. But when surgery is found to be necessary it’s quite effective in realigning the eyes.
Dr. Mike Patrick: What do you do exactly to get the eyes aligned again?
Dr. David Rogers: You have to understand many parents are under the misconception that we’re doing something to strengthen the weak muscles in the eye. It would be very rare to have a muscle that’s so weak that it’s the root of the problem.
The problem is really in the neuro centers in the brain that control the eyes. Now there are some diseases and one would be Duane syndrome, for example, where the muscle is abnormal. But in most typical and the most common types of strabismus that we see are the esotropias and the exotropias.
These are really not muscular issues. They are neural control issues. What we do is we try to find out what the relax position is of the eyes. Where did the eyes want to be when they’re completely relaxed or dissociated from each other. We measure that angle and we adjust the eye muscles either tightening them or weakening them to allow the eye to now be straight.
Dr. Mike Patrick: And you do that by shortening the muscle?
Dr. David Rogers: Sometimes we shorten it. If we are going to tighten it up we cut a segment out and then sew it back on into its original position.
Dr. Mike Patrick: So whichever side the eye needs to move toward you shorten that muscle to bring it into alignment that way.
Dr. David Rogers: Yeah. Typically though we’d try to do a weakening procedure on a muscle first if we can. The tightening procedure is not as reversible. I can weaken a muscle if it’s pulling in too much and we’ll weaken the inside pulling muscle known as the medial rectus by cutting it off of the eye and moving it back in graded amount and reattaching it to the eye.
Now in that shortened position it can’t pull as hard. If we didn’t like that position, if we had a bad outcome later and we needed to adjust it later in life we have the freedom to move that muscle forward again. The tightening procedure that you mentioned actually cuts a segment of the muscle out. Once it’s gone you can’t really put it back in there.
Dr. Mike Patrick: Yeah. For those of you out there who are driving right now, hopefully your eyes aren’t watering too much. I know my wife is very squeamish with eyes and so I’m sure there are lots of folks out there who hear cutting a muscle off the eye and reattaching it is not the most pleasant thing they hear about.
Dr. David Rogers: I’ve had many residents pass out.
Dr. Mike Patrick: Ophthalmology residents?
Dr. David Rogers: Even ophthalmology residents.
Dr. Mike Patrick: Yes. Yes. But that gets better, right?
Dr. David Rogers: Yes. Mostly medical students.
Dr. Mike Patrick: And we really kind of talk about this, I mean the biggest complication that can arise from an untreated strabismus is going to be amblyopia. Are there other complications that could arise from not treating this?
Dr. David Rogers: Yeah. I think most parents are concerned about depth perception issues and they can occur if you have amblyopia and perfectly aligned eyes or the combination of amblyopia and strabismus. So if you go to a 3D movie and you try to watch that movie and see the image pop out at you, if you cover up one eye it suddenly becomes a flat image and you don’t see it at 3D. It doesn’t matter if you cover your right or your left eye, you lose the 3D effect.
So people who have misalignments of their eyes they don’t see 3D images well. And that is a part of what depth perception can be. Now fortunately, not all depth perception is binocular. I can cover one eye and look at you and you don’t become a flat photograph. You still have structure and shape. So there’s image parallax and motion and perspective and lighting that’ll help us determine that there’s depth in the world.
Dr. Mike Patrick: Sure.
Dr. David Rogers: So that’s one issue. One other point. One other major point that’s not often talked about is the real burden that this can be on families. I hear people come and tell me that they’re sick and tired of somebody in the grocery store mentioning that their child’s eyes are not straight.
And I’ve had adults who had not had this condition treated who will just sit there almost tearfully telling me about the woes that they’ve had in their life. People look at them as if they are not smart enough. They’ve been passed up for raises and promotions or they didn’t get the job.
Studies have actually been done to look at this where we know now that the average earning potential of somebody who has strabismus that’s noticeable to others is actually lower than somebody whose eyes are straight.
We also know that if you have an application that’s a great perfectly qualified application for a job and you attached a picture of somebody who has straight eyes to that application and you’d send out the exact same application with a photograph of somebody with strabismus, that person who has straight eyes is the one who will be offered the interview.
So it can have a tremendous social and financial impact throughout somebody’s life. That’s why we like to get that treated early.
Dr. Mike Patrick: I can really understand that. I have glaucoma, personally, and have had a trabeculectomy in one eye and have a bleb and little ptosis in one eye. And I am so self-conscious of it. Some people notice right away and other people don’t notice at all and are surprise when they hear it, but I totally understand what you’re saying there with that.
Dr. David Rogers: Yeah.
Dr. Mike Patrick: What about lazy eye treatment? Are there any complications that can arise from that?
Dr. David Rogers: Well it depends. There’s really no complication of wearing glasses that we know of. Now in certain cases if you were out playing sports and a ball hits you in the glasses, street glasses can break and cause damage to the eye and even the face. So we do recommend that you wear sports glasses or rec specs, for example, appropriate eye protection for what sport you’re playing.
So from glasses alone probably not. But with the patch and the Atropine treatments that we’ve talked about there are complications in both and there are benefits to both. Now probably the most common problem that we see when a child is wearing a patch is the social impact that that has. They don’t want their friends to see it and if they do they get a lot social pressure for it. But that’s something that it can be dealt with.
The adhesive on the patch itself can cause allergic reactions on the face. Now as you know, most of the children that are being treated are young and a child’s skin is much more sensitive than the adult skin and facial skin is even more sensitive than the skin on your arm.
If you’ve ever had a Band-Aid on your arm for more than a few days and peel it off, you’ve seen that redness that can be caused by the adhesive. So if you’re putting a patch on a child’s eye and removing it everyday you can get skin breakdown around the eye and that’s a problem.
Now, Atropine treatment, any medication can cause an allergic reaction. So you have to be aware of those things, but it can also cause blurring of the vision. What we’re actually doing is blurring the vision by dilating the pupil. The pupil is so large then that it can cause photosensitivity or sensitivity to light when they go outside. So sometimes we will prescribe sunglasses or have them wear a brimmed hat. Those issues
Dr. Mike Patrick: Sure. When an eye has to be corrected surgically, is that for good or could the alignment become an issue again down the road?
Dr. David Rogers: Well there’s good date on this that if you have eye muscle surgery you have probably 1/10 to 2/10 chance of needing additional surgery at some point again in your life. And that’s not a risk that you can outlive. It’s really a lifetime risk. This is not an eye muscle problem, remember. It’s a problem with neural control in the brain.
And you can realign the eyes when you’re very young and if you do a lot of growing sometimes those factors can cause misalignment of the eyes. And then if you don’t have binocularity, if your eyes do not work together at all, you have a higher chance of needing additional surgery.
In those patients that have intermittent strabismus, that means eyes that are misaligned sometimes but are straight at others, those people have an ability to control their eye some of the time. And if you can get their eyes more aligned towards the center, straight ahead position, they have the ability to keep them aligned themselves for the long haul.
Dr. Mike Patrick: Sure. What is the long-term outlook for kids with lazy eye? Obviously, there’s the chance that it can become intermittent and you can have more problems down the road, but for the average kid who presents as a baby with strabismus are they expected to have issues down the road?
Dr. David Rogers: I think that parents should be prepared for additional issues. It’s not something that just one surgery that realigned the eyes is going to fix. These people also have other problems. Typically, amblyopia or refractive errors and all these need addressed and this is something that needs to be followed for a lifetime.
Dr. Mike Patrick: Is there a way to prevent this from happening in the first place?
Dr. David Rogers: Well prevention should be focused at identifying those risk factors and then mitigating those risk factors as early as possible. So you could identify a child who had an anisometropic refractive error very young before his eyes started to drift and maybe prescribe glasses and prevent the amplyopia from developing.
We rely on good screening programs to identify these children. So this is your pediatrician and follow up with your pediatrician for your well-child visits, that you allow your children to have their visions screens down at school, those kinds of things. They will identify these issues and then get you referred to the appropriate people.
Dr. Mike Patrick: Speak a little bit to the controversy that I mentioned at the beginning when the optometrist wrote in and said, “No, this is something that we can see.” And I think her point really was don’t avoid the optometrist because if we see that this is going on we are going to refer to a pediatric ophthalmologist.
So I think really she wasn’t disagreeing with what I was saying. But this obviously if this truly is what you have, a pediatric ophthalmologist is who you need to see. Is that reasonable?
Dr. David Rogers: Well you’re asking somebody who’s obviously going to be biased. And so without that bias in mind, I will have to agree with your optometrist to the extent that I know that optometrists are fully capable of performing this comprehensive eye exam.
I personally believe that a pediatric ophthalmologist is the best suited professional to provide treatment and long-term care for these children. But there are exceptional optometrists out there who do a great job. And I sometimes can work very effectively hand in hand with these people.
Let me give you an example. I’ll have a patient that will come to me for three hours away. It’s quite a burden on that family to come and see me. There are very few of us as pediatric ophthalmologists out there.
And if I can prescribe a treatment regimen and all they need to do is follow up with me in two or three months to check the vision that can be done locally. And I can work hand in hand with a local optometrist if we can find one who’s willing to see children. That tends to be a problem in some of these outlying areas. But if we can, it can really assist that family and be a benefit to that child.
Dr. Mike Patrick: Sure. We really appreciate you stopping by to talk about these items. I do have a lot of links available over in the Show Notes for PediaCast 231 at pediacast.org. We’re going to have a link to the pediatric ophthalmology program here at Nationwide Children’s Hospital. Also strabismus information from the Nationwide Children’s Health Library.
The American Association for Pediatric Ophthalmology and Strabismus has tons of wonderful information for parents out there, including information on strabismus, amblyopia, patching tips for parents, how you do strabismus measurements, information about the surgery, adult strabismus, pseudostrabismus. So if you’re really interested in knowing more about these things I definitely encourage you to check out the American Association for Pediatric Ophthalmology and Strabismus website and we’ll have links to all that in the Show Notes for you.
Also a plethora of other links as well. PediaCast on Pinterest. I have talked about the seizure and epilepsy guide for parents and the medication update for infantile hemangioma, all those things will have links in the Show Notes. So there’s going to be a bunch of links for this particular episode.
Now before you go, one more thing I wanted to ask you and with the holiday season approaching here before we know it, one of the questions that we ask every guest on PediaCast is it’s a passion of mine that families do things together that don’t always involve television screens and video games.
So just thinking back to your childhood or even now, what’s your favorite board game or game to play if parents don’t have that they may want to think about as a Christmas gift?
Dr. David Rogers: Oh my! Well, we always sat around and played Monopoly and sometimes those games could last for days and we had a lot of fun.
Dr. Mike Patrick: Yeah.
Dr. David Rogers: You did mention Halloween, might I just make a shout-out to all the parents out there who will be looking at costumes and just to warn you against cosmetic contact lenses. You can pick these up at grocery stores and local cosmetic stores but they should only be prescribed by an eye doctor. And they can cause more harm than you can imagine.
So they have to be prescribed and fitted appropriately. So please don’t allow your children to get a hold of cosmetic contact lenses.
Dr. Mike Patrick: Yeah. So if your kids are going out in the street tonight or going to a party, nothing in the eyes.
Dr. David Rogers: That’s right.
Dr. Mike Patrick: All right. We really appreciate you stopping by and talking to us about strabismus and amblyopia and lazy eye. I want to remind you that iTunes reviews are helpful and so are links on your webpages and mentions in your blogs, on Facebook, in your Tweets and on Google+.
Be sure to join our community by liking PediaCast on Facebook, following us on Twitter, hanging out with us on Google+ and of course stopping by our new Pinterest boards and repining your favorite episodes and news stories.
You can also swing by the Show Notes at pediacast.org to add your comments on today’s show. We also appreciate you telling your family, friends and neighbors about the program. And don’t forget to talk us up with your child’s doctor at your next well check-up or sick office visit.
We also have posters you can download and hang up wherever moms and dads hang-out. And you can find them under the Resources tab at pediacast.org. One more time, if you want to get a hold of me it’s easy to do, just head over to pediacast.org and click on the Contact link. You can ask your question or suggest a show topic.
You can also email firstname.lastname@example.org or call the voice line at 347-404-KIDS. That’s 347-404- K-I-D-S. If you do email or use the Skype line to call us, make sure you’d let us know who you are and where you’re from.
All right. Well that wraps up today’s show. Until next time, this is Dr. Mike saying stay safe, stay healthy and stay involved with your kids. So long everybody!
Announcer 2: This program is a production of Nationwide Children’s. Thanks for listening. We’ll see you next time on PediaCast.