Lecture: Approach to the Patient with Double Vision

DR GOLNIK: Welcome to an Orbis/Cybersight webinar. This one is on the practical approach to the patient with double vision. I’m a neuro-ophthalmologist at the University of Cincinnati and the Cincinnati Eye Institute, and have been practicing pretty much just neuro-ophthalmology for the last 30-plus years. So we will continue with our objectives. When we’re done with this webinar, and of course, it’s only about an hour, so this is a lot to cover — we’re going to describe the important historical points in the patient who has double vision. We’ll be able to list what I call the fellow travelers of double vision. And then describe the importance of determining the pattern of misalignment. Now, this webinar is really mostly aimed at getting the correct diagnosis, as opposed to managing all of these conditions. That would take a really long time. That said, we are planning another webinar that will sort of add on to this one, where we’ll talk more about the management of some of these conditions. And there will be a Q and A at the end of this. So you can type in questions. I would ask — don’t just start typing in a bunch of questions now. Because I may answer those questions during the talk. And then I won’t know if your question has been answered or not. So go ahead and type them in when you think I’ve covered something, and ask questions in the Q and A, as we proceed, and then we’ll get through as many of those questions as possible at the end. So I think the first thing, when you see a patient who has double vision, and I know in my clinic, oftentimes half the patients are sent to me with double vision. And the first question is always — as I tell my patients — why do you have double vision? And then the second question is: What do you do about it? As I said, in this webinar, we’re going to mostly try to answer the “why do you have it?” Because a lot of times I see patients and nobody asks that question. They go to the — what do you do with double vision? But you have to answer the first question, why do you have double vision. The first question that is very helpful is: Is it monocular or is it binocular? Monocular means it’s there with either eye covered. It might be monocular in one eye or in both eyes. The point is, if the patient has double vision that is present with one eye closed, it is monocular. Usually patients with monocular double vision don’t describe two separated images. They describe a superimposition or ghosting of images. When people tell you it’s monocular, you say — I bet it’s ghosted. And they say yes, that’s exactly right! The important thing about monocular double vision is virtually never neurologic. So it’s caused by simple things. Half a diopter of uncorrected astigmatism can cause monocular double vision. Mild to severe corneal scars, cataracts, subluxed lens or implants. Rarely an epiretinal membrane can pull on the retina and cause monocular double vision. And there is something that’s neurologic, called palinopsia. It’s very, very rare. As a neuro-ophthalmologist with 30 years of experience, I think I’ve seen it once. So you can imagine how often you see it. In palinopsia, if you ask the patient about their double vision, it’s not really what we think about as double vision. It’s when you see something, say a flower, and then later on, you’re looking at something else, and you see the flower superimposed on whatever you’re looking at. So that’s not what we typically think about as double vision. Where you see two of the same images, side by side, or up and down. So once you talk to the patient, you’ll realize — oh, that’s not what we think about as true double vision. And if the person has monocular double vision, there are very simple tools. Usually pinhole vision will get rid of it. The patient who is worried about being in my office, because I’m a neuro-ophthalmologist, and they’re thinking about tumors and multiple sclerosis, the patient can pretty much understand that if you throw up the pinhole and get rid of the double vision, it’s not some bad neurological problem. You can refract them, if the pinhole gets rid of it. Corneal topography may be helpful. The slit lamp exam, of course, and nothing comes up, look for the epiretinal membrane. But the bottom line is: If it’s monocular, it’s not neurologic. We screen all the referrals that I see. Because many patients are referred to me who don’t have neurologic problems, and I try not to see those. Since I’m a neuro-ophthalmologist. My assistants, who schedule my patients, will ask the patient: Does it go away when you cover either eye? And if the answer is no, I cover my left eye and it’s still present in my right eye, then they say: Dr. Golnik will not see you. Have your daughter call him and explain why they’re sending a patient with monocular double vision, which is virtually never neurologic. So the rest of this webinar will concentrate, of course, on binocular double vision. Which may be neurologic. It may not be, but it may be. And you always want to know: Is it constant, or is it not? Is the double vision present morning, noon, and night? Or does it come and go? If it does come and go, if it is intermittent, you want to know about relieving and exacerbating factors. Is there anything that makes is happen? *makes it happen? Is there anything that makes it go away? So you want to know about those factors. We’ll try to talk about those things. The first part of the talk will be on the principles, and the second talk, we’ll talk about patients, individual patients. Show a lot of videos and try to illustrate the points that I’m making here. And then of course the duration is important. How long has the double vision been present? And the reason that’s important is that one of the more common causes of double vision that I see as a neuro-ophthalmologist is the microvascular or vasculopathic cranial nerve palsy. III, IV, or VI. And it’s related to hardening of the arteries. And that virtual real always goes away in three months. So if the double vision is there for longer than three months, I start to think about other things in the differential diagnosis. If it’s less than three months, then that microvascular still is potentially on the list of the differential diagnosis. So is it greater than or is it less than three months? I want to know that. And then finally I often ask people: Is this an isolated vision problem? If you just say to the patient: Is there anything else going on? They’ll often say something like: Well, maybe it aches a little bit around my eye. Sometimes my eye… Not your eyes. Not your eyes. Anything else with the rest of you? To try to really get at this, I use — if you look at my video — I use the arm gesture. So I raise my hand from their head to their toe. I say: No, anything else. Oh! You want to know about something else. Well, my right arm has been a little weak lately. Well, that might be relevant. Remember, you are an eye doctor, and patients often think all you care about are their eyes. In neuro-ophthalmology, we care about the rest of them. We want to know what else is going on. And occasionally I have a patient, a resident sees the patient, one of my student doctors, sees the patient. The patient — there’s a wheelchair in the hallway. The resident comes out to tell me about the patient. I ask them: What’s the wheelchair for? They have no idea what the wheelchair… So find out about other problems! They may be related to the double vision. I’m hoping they say no. This is an isolated vision problem. That’s all that’s going on. So then we get to the examination. And what I call the fellow travelers. And the fellow travelers include things other than the eye movements. Of course, you’re going to look at the eye movements and the alignment. And we’ll talk about that. But there are other things that you really want to pay close attention to. The eyelids. So in this case, in this photo you’re seeing, this person has marked upper and lower eyelid retraction. This is almost always going to be thyroid eye disease. You don’t need to look at the eye movements to know what the problem is in this case. There are other eyelid findings that are important to look for. Here’s a patient with some ptosis on the right. And as he looks upward, what happens? He has this very impressive fatigable ptosis. Within myasthenia gravis. Look closely at the lids for this. Here’s a patient with something called Cogan’s lid twitch. And you can look at her left lid. Which is obviously droopy. And once in a while, and I’m gonna isolate that lid, you’re gonna see a little twitch. Right there. You see that little twitch? Keep watching the left lid. There it is again. That little twitch that you’re seeing. It’s a Cogan’s lid twitch. That’s something we might see — not necessarily, but might see — in myasthenia gravis. So look closely at the eyelids. And if you see a patient with ptosis, you can do an ice test. This is a very simple test. Of course, you need ice. But it’s a two minute ice application to the ptotic lid. There has to be at least a couple of millimeters of ptosis. Because you’re trying to judge improvement in the ptosis. More than 1 millimeter of improvement is a very sensitive and specific indicator of myasthenia. This is an article we wrote now, more than 20 years ago, about the utility of the ice test. Here’s an example. Look at the left upper eyelid. Here’s our fancy ice pack. A rubber glove with ice. Two minutes go by. You ask the patient to blink once and look straight ahead. And you see a very positive ice test. Now, this has to be judged. And we’ll show it again. In the matter of seconds. 15 or 20 seconds at most. Because that lid will heat up very quickly, once you’re done with the ice test. So again, significant ptosis prior to the ice test. And then marked improvement. So a very positive ice test. Again, a test for myasthenia gravis other causes of droopy lids do not cause a positive ice test.

We also want to look closely other than eyelids for either ptosis or lid retraction. We want to look closely at orbital signs. Is there exophthalmos which seems apparent? This patient also has lid retraction, which seems important. This is a patient with thyroid eye disease that’s very unilateral. But we can look at other signs, orbital signs, and if you don’t have a Hertel exophthalmometer, obviously the best way to measure exophthalmos. If you don’t have one, you can look down across the corneas. That can make it more apparent. You can see in the photo definite exophthalmos. You can look for chemosis. This patient has marked chemosis which no one is going to miss. But look for subtle chemosis. On the bottom, you see a red conjunctiva. And these are actually very dilated conjunctiva in a patient with cavernous sinus fistula. But look on the lower right. The patient’s left eye has dilated conjunctival vessels. This patient has a low flow or dural cavernous sinus fistula that is less fulminant than the direct cavernous sinus fistula. That was a sign that they had a fistula causing double vision. Don’t forget to try trigeminal nerve and facial nerve function. Trigeminal nerve function is very easy and quick to check. Take a cotton tip or tissue paper. And just touch each side of the face and ask is it about the same. Why? Because the trigeminal nerve starts in the brain stem near the 6th nerve. And other nerves that are in the general proximity — facial nerve, same thing. So we want to know: What is the orbicularis function like? This is a patient who doesn’t have a facial nerve problem, but we’re checking the orbicularis strength. And I’m asking her: Hold your eyes closed as tightly as you can. Keep them closed. She says: I’m trying! Look what happens. Very easy to open her lid. And when I let go of her lid, it just kind of flops back into position. Almost no orbicularis tone. She doesn’t have bilateral facial nerve palsies, which would be rather rare. She has myasthenia. So remember, it can cause a droopy lid, but it can also affect the orbicularis muscle. We want to check closely orbicularis function. It takes this long. A few seconds. But it’s important in your patients with double vision. And then something you can check when you walk into the patient’s exam room — the head position. In the photo at the center, the left photo of the young lady, this is a young lady, an MRI technician. I was walking through the MRI suite one day. And she said… I know you’re a neuro-ophthalmologist. I get occasional double vision. She had a left head tilt. I said I bet I know what you have. Sure enough, congenital fourth nerve palsy. She had a head tilt all her life to compensate subconsciously. Didn’t know her head was tilted. The guy on the right had recent onset of double vision. I walked into the room and said: You have double vision? He said no. But he had a right head turn because he had a right 6th nerve palsy and he knows subconsciously that if he turns his head to the right, he minimizes the need to adduct the right eye and his eyes are straight. As soon as I told him: Straighten your head out, he said: Oh, now everything is double. And he would see double. So look at the head position. You can notice that people with thyroid eye disease often have a chin up position. Because they have a tight inferior rectus on one side, compared to the other. And so they know consciously or subconsciously that when they tilt their chin up, it minimizes the misalignment. Okay. So those are the fellow travelers. You want to look at the lids. You want to look at orbital signs, you want to look at head position. And then of course you’re going to look at eye movements. And everyone is, I think, pretty much gonna look at the ductions and the versions. That’s pretty straightforward. But of course you need to know the pattern of ocular alignment. Doctors sometimes will call me and say: Oh, yes, I have a patient. They have a 10 prism diopter esotropia. They’re very proud, because they measured with prisms. But what I want to know is: Okay. What happens when they look to the left? And what happens when they look to the right? Because just telling me there’s a 10 prism diopter esotropia — that’s not the pattern. That tells me they have an esotropia. But it doesn’t tell me what happens when they look left, right, up, and down. You need to know that to know what the diagnosis is. So it’s very simple. Thankfully, our gold standard for measuring misalignment is simple. Cover-uncover testing and cross-cover testing. Hirschberg, looking at the corneal light reflex, as I tell my students: I don’t want to hear about it. If the patient can talk, and follow commands, and look at a distant target, I don’t want to hear what you think about where the light reflex is. I don’t care. What I want to know is — I don’t want to know do they look misaligned. I want to know: Are they misaligned? And that’s why you do a cover-uncover and cross-cover test. Let’s look at some examples. This is pretty basic. But here’s a patient. And if you just look at her, she’s looking at a distant target, I always have my patients look at a single letter at the end of the room. I say: Keep your eyes on that letter. And as I cover each eye, I say: You’ve got it? You’ve got it? You’ve got it? To make sure their eyes are on the target. Sometimes the patients won’t automatically look at the target when you cover an eye and the other eye is looking that way. I always say got it? Got it? Got it? I cover the other eye. The video looped. Got it? Yes, I’ve got it. Now, when you look at her, when the occluder is not covering either eye, her eyes look pretty straight. And when I show this to neurologists, they say: Well, her eyes look straight. Yeah, that’s the point. They may look straight, but her eyes are not straight. Whenever we cover her left eye, nothing happens. The right eye stays on target. Whenever we cover the right eye, both eyes move. The left eye moves out. Her eye is esotropic. She has an esotropia. She’s a strabismic amblyope. She didn’t have double vision, but she’s a good example of someone whose eyes look straight but they’re really not. She’s fixating with the non-amblyopic eye, unless you make her fixate with the left eye. So she’s esotropic. There’s a manifest misalignment. Here’s a young fellow who has intermittent double vision. And you can see when we do a cover-uncover test, we watch the uncovered eye only. Don’t watch the eye that’s covered when you take your hand away. And you’ll note there is no movement. So he is orthotropic. But he has intermittent double vision. He’s not having double vision right now. So cover-uncover test. Orthotropic. You only look at the eye that is uncovered. But when we look at the same individual and we do a cross cover test, you can see he has an obvious… Exo deviation. An exophoria. So he is exophoric. This is a latent misalignment. Now, having a phoria versus a tropia doesn’t say anything about the underlying cause. If you have a mild 6th nerve palsy, you may be esophoric. You would rather find a patient with the tumor pushing on their 6th nerve when they’re esophoric. It’s milder. Sometimes people don’t understand tropia versus phoria. It’s about how well the patient can control the misalignment. We’ll measure the misalignment. You can use a prism bar, or prisms, put the prism up until the patient’s eyes don’t move, and you can quickly turn his head from left to right. Leave the prism bar there. Is he neutralized? He is. He has a comitant exophoria. Comitant means about the same misalignment in each direction. Okay. Those are the principles. Important thing. Look at the fellow travelers. You have to determine the pattern of misalignment. It’s not enough to know what happened just in primary position. And ideally, of course, we’re gonna measure this with prisms. All right. Let’s look at some cases. We’ve got a bunch of them.

>> Don’t turn your head. Just with your eyes.

DR GOLNIK: In this patient, I am gonna get a measurement in primary position, just so I know what her measurement is. You can see that she’s obviously esotropic in primary position. Most of you can probably tell me what the diagnosis is. She’s 60 years old. Has hypertension and diabetes. And this is sudden onset. It is constant. And you can see that when she looks to the right, her eyes look pretty straight. We can check that by doing a cover-uncover test. But the more she looks to the left, the larger these tropias, and she basically has a complete left abduction deficit. And she had a microvascular left 6th nerve palsy. Am I gonna measure her alignment in all directions? I’m not. Because it’s so obvious. A complete 6th nerve palsy, I’m not gonna necessarily measure things. Although I do get a measurement in primary position, because what are we gonna do with this patient? I’m gonna see her in six weeks and say: Hey, you’re gonna be getting better. She’s gonna come back in six weeks and she might say: You know, I’m not getting better. You told me I would. And yet her measurements will be improving. She doesn’t think she’s getting better, because she still has double vision. But you can reassure her and say: Ah, our measurement last time was 40 prism diopters. Today it is 20. You’re twice as good, but you still have double vision. So in this case, the pattern of misalignment is obvious. What about in this case? So here’s a fellow who has double vision. We’re looking at his versions. And I’ll let you look and see what you think. We’re not doing the question and answer thing here. But I quiz my residents on this patient frequently. And what you’ll hopefully notice is that when he looks to the left, his eye movements look pretty good. But that right eye is not quite abducting all the way. Watch that again. So the left eye abduction looks good. The right eye, not quite. You might say… That’s hard to tell. And that’s why you’re going to look at his alignment. So let’s see. If we’re right… And the right eye is not abducting fully, what should happen? Well, he probably has an esotropia in primary position that would worsen in right gaze. So let’s look at his alignment, just at cover-uncover test. And we can see that indeed he is esotropic. See the left eye move out a little bit? And he’s fixating with the right eye. Now, when he looks to the left… We do our cover-uncover testing… He’s good. In fact, he says… Oh, when I do that, I turn my head way to the right and look to the left, my double vision goes away. You’re right so far. That would be consistent with a mild right abduction deficit. When he looks to the right, he says… Oh, it gets farther apart. Now he’s switching fixation. You can see his esotropia is larger. And of course, you can document this with prism. And you might find… Oh, to the right, he has a 12 prism diopter esotropia in primary at 6 and to the left, it’s 0. And incomitant. Non-comitant misalignment. Consistent with a mild right abduction deficit. And he is 60. And you might say… Oh, well, he’s 60. He’s got high blood pressure. It could be the same thing we just saw. This could be a microvascular 6th nerve palsy. It started a couple weeks ago. So that’s within the time frame. But then again, we’re gonna ask him other questions. Is there anything else going on? And he said: Well, you know, it’s funny. Since this happened, I’ve noticed that when I’m chewing and eating, a little bit of saliva will come out the corner of my mouth. And I have to sort of dab the corner of my mouth. So we’ve ascertained that he has a mild right abduction deficit. What else do we want to know? He’s esotropic in right gaze. We want to know about other fellow travelers. And so I’m trying to show you here that he has slight right 7th nerve weakness. It’s a little bit tough. It’s very mild. But that’s why he’s having the saliva running out the corner of his mouth. Look. When he looks up, he braces his forehead and wrinkles his brow. You can see there’s a bit of an asymmetry. The right brow is just not quite the same. When I checked his sensation, because we want to know about V and VII, if we think there’s a 6th nerve palsy, he says… It’s not numb, but it doesn’t feel the same when you put the tissue on one side of my forehead, the right side of my forehead. We say ah-ha. This might be something completely different. He doesn’t just have an isolated right 6th nerve palsy. He has a right 5th, 6th, and 7th nerve palsy. That’s a different scenario. We always want to check the adjacent cranial nerves. In this case, V and VII. And here we have a line drawing of a cross section through the pons. And as you know, the 6th nerve nucleus is here. But the 7th nerve fascicle runs around it. The 5th nerve — the spinal nucleus of the trigeminal nerve right here. So these things are close by. So you could have a lesion in the brain stem. And also remember… These nerves run out from the brain stem, forward. So a cerebellopontine angle tumor could cause V, VI, and VII. Clearly this individual needs an MRI. A CAT scan would be a very poor second choice. The MRI would be the test. And of course you’re going to do it with gadolinium. Never order an MRI without gadolinium. Or dye. And interestingly, the radiologist called me and he said: Hey, we found this guy’s problem. Looks like he had a little stroke. A little infarct, maybe. It looks old. In the pons. Where this red arrow is. And he said: Yeah, it’s right there in the left pons. I said… Wait a minute. I saw this guy a few days ago. But I think he had a right 5th, 6th, and 7th. Not a left 5th, 6th, and 7th. He said it’s in the left pons! Are you sure you labeled the films right? He didn’t like that very much. I told him whatever neuro-ophthalmologist is gonna tell the radiologist. Send me the films. I want to see the pictures. What do we see on the pictures? They saw this little thing in the pons where the red arrow is. And they completely sort of fixated on that and neglected this enhancing mass in the cerebellopontine angle depicted by that yellow arrow. This was metastatic lung cancer that ultimately killed the patient. The answer to that story is: Always look at the radiology. Look at the films. You might say: I’m not that good at doing that. If you’re not, that’s okay. But if you think there’s something going on, and somehow the MRI comes back as normal, call the radiologist. Say: Hey, are you sure you’re looking where I want you to look? I’m really suspicious about this. I have a whole other talk about missed MRI findings and CAT scan findings from radiology. So the moral of that patient was: Check those fellow travelers. Check those adjacent cranial nerves. So this is a very common scenario. At least in my practice, and certainly in other practices. This is a 71-year-old woman who has had double vision for at least several months. Patients who have this problem, you ask them: How long has it been going on? I don’t know. Five, six months. Maybe even longer. It started way in the distance. When I’m driving or something. I would see two cars. Or at night, I would see two sets of headlights, and I knew there was only one car. So the double vision is at a constant distance. But it’s not present at near. It’s binocular. It’s horizontal. The patient doesn’t really think it’s variable. Except for that issue of not occurring at a near target. There was mild ptosis that was bilateral. I’m sorry. There wasn’t ptosis in this case. There was no other muscle weakness. Arms, legs, et cetera. Chewing, swallowing. And on exam, there was very mild ptosis. The patient didn’t really notice it. The ductions and versions, full D and V, were full. So eye movements looked fine. But when we checked the alignment, we found a small esotropia. Distance. Of 4 prism diopters. About the same up and down. Slightly more in left and in right gaze. So I would look at these measurements and say… Well, that’s relatively comitant. And the question is: What’s going on? What are the possibilities? Well, you always have to think about myasthenia, because myasthenia can cause virtually any pattern of misalignment. She does have some mild ptosis, but it doesn’t vary. In this scenario, by far the most common thing that’s gonna cause this, and some of you may know the answer. I’m not gonna ask the question, but if you think of the answer, I’m gonna show it now… Is something called the sagging eye syndrome. We used to call this divergence insufficiency. I don’t think people are calling it that much anymore. Although my patients like the term divergence insufficiency a lot more than they like the term sagging eye syndrome. And what Demer and associates did, now eight years or so ago, is they used high resolution MRIs in these patients. And they looked at the anatomy of the rectus muscles. The pulley locations. On the globe. And the lengths of the lateral rectus, superior rectus, band ligament, and rectus muscles. And looked at facial features. And what they found was… That this lateral rectus-superior rectus band, which is… Hopefully you can see my pointer, which is right here, between the lateral rectus and superior rectus… And here you can see again… Would be disrupted. And the pulleys would be misplaced. And when that happens, it can create a little difference in the force vectors of these muscles. And it can cause most commonly, in my experience, an eso deviation. But it can cause a little vertical misalignment too. And so in this subsequent study from just a year or so ago, the same group looked at the prevalence of the sagging eye syndrome, in adults with double vision. And so this is just all comers. They looked at all new patients with double vision, over the age of 40. Over this five-year span. And they had 945 patients. So a pretty busy practice with double vision. They found the mean age was in the mid-60s. And they found that the sagging eye syndrome was more common, the older you got. A little more common in women than men. So that under the age of 50, it was a pretty small component. 4.7%. So under age 50, that’s a little bit of a red flag for me. I’m gonna want to think about other things a little more strongly. But look at this. Over age 90, more than half of their patients with double vision, just any kind of double vision, had this sagging eye syndrome. And oftentimes there was some sort of cyclo-vertical component. So sagging eye syndrome — it’s a very common entity, if you are over the age of… Well, it’s more common as you get over the age of 40.

>> Straight ahead.

DR GOLNIK: All right. We’re gonna move on to another topic. So here’s a fellow… I think he was in his 70s. And he’s had double vision for just a week or two now. And we’re looking of course at his versions here. And I’ll let you look and sort of digest this a little bit. And we can talk about the diagnosis. When he looks to the left, his eyes are pretty good. And in fact, he doesn’t have double vision when he looks to the left. But he does when he looks to the right. And hopefully you’ll notice the relevant finding. He’s got good vertical eye movements. But he has a left adduction. AD-duction deficit. So when he looks to the right, you’ll see the left eye just doesn’t adduct all the way. There you go. The other thing you’ll notice when he looks to the right — look at his right eye when he looks to the right. You’ll see there’s a little bit of abducting nystagmus. So this is a moderate internuclear ophthalmoplegia. A left INO. Left INO. And this can be much more subtle than this. There can just be slowing of the adducting saccade in an INO. It’s a very obvious left INO. Sometimes my students will say: Oh, I think this person has a third nerve palsy. Balls the eye doesn’t adduct. But the elevation and depression of the eye are normal. And there’s no ptosis or pupil involvement. If you see an isolated adduction deficit, it’s virtually always gonna be an INO. And INO, of course, is due to a problem in the MLF, the medial longitudinal fasciculus. This inner neuron that runs from the horizontal gaze center, the PPRF, up to the medial rectus subnuclei, in the third nerve complex. So there’s an ipsilateral adduction deficit. Because that medial rectus is not getting the right innervation. And then there’s also this contralateral abducting nystagmus, because of a problem with the pause neurons. Long story. Don’t need to know about it. But an INO. So this is a pattern that you need to be aware of to make a diagnosis. And in a gentleman like our gentleman, who was older, let’s say older… I used to say older than 50. Now it’s older than 61, since I’m 61. But this is usually an ischemic problem. A small lacunar infarct in the pons. Usually in the pons. And so here’s, again, that cross section we showed earlier. You can see the MLF in the center. Right next to one another. So a lesion — just a very small lacunar infarct in the MLF will do this. You may miss this on an MRI. I just had a patient — we wrote a paper, myself and colleagues, I think we had 75 internuclear ophthalmoplegias that were ischemic. But only half were seen on the MRI. Why? The MRI doesn’t look at every square millimeter of your brain. There are slices every so often. If you have a small lacunar infarct, and the slices happen to be one on either side of the infarct, you won’t see it. It’s still ischemic, and usually when they’re really small like that, usually they resolve with no treatment. Usually. So here’s another patient that I think everyone will very quickly identify the pattern of alignment. You don’t have to get out your prisms to know the pattern in this case. He’s got obvious left ptosis, and the left eye does not depress well. It does abduct well. It does not elevate or adduct well. The pupils, which — I’m not showing you their reactivity — are equal. But this person has what hopefully you will think of is an obvious left third nerve palsy. Obvious left third nerve palsy. But I don’t think anyone is gonna miss the diagnosis. As I say, this patient read the textbook and he knows what he’s supposed to look like. How about this patient? This is a guy in his early 60s. Hypertension. But what do you think about his eye movements? I’ll let this run once or twice for you to take a look. So of course he has double vision. That’s why we’re showing him. And let’s look at his pupils. He’s got dark brown irises. But I think you can see, hopefully, that the left pupil is a little larger than the right. So this guy has a left third nerve palsy too. It’s not that obvious. But his left eye doesn’t depress all the way. It doesn’t adduct. There’s a little bit of sclera there. You compare it to the right eye. Doesn’t quite adduct. And it doesn’t elevate all the way. Now… This is someone where you are gonna do your cover-uncover testing. And what will you find? You’ll find that when he looks up, he has a left hypotropia. And when he looks down, he has a left hypertropia. And when he looks to the right, he has an exotropia. And that’s the pattern of third nerve palsy. Whether it’s obvious, like our previous patient, or whether it’s mild, it doesn’t matter. Right? Maybe his aneurysm is just beginning to push on that third nerve. In this case, he had pharyngeal cancer causing this left third nerve palsy. Although it was very mild when we saw him. The point is, you’ve got to identify the pattern, and then you’re gonna make the diagnosis in this case of the third nerve palsy. So here’s another patient. He’s had double vision for at least a month. Probably closer to six weeks. And the question is what’s going on. I showed this video to my residents. They often don’t know. And they look at his eyes and say… Okay. He’s got double vision. Let’s look at these eye movements. You can see clearly I think it’s obvious that he’s esotropic. Right? And when you look at his horizontal eye movements, most people will say… Well, it looks like he’s got bilateral abduction deficits. He does have bilateral abduction deficits. And they start to tell me about… Let’s see. What can cause bilateral 6th nerve palsies? Not a lot. So they thought… Maybe myasthenia could do this. Which is true. You could have bilateral abduction deficits from myasthenia. You could have bilateral 6th nerve palsies from a clival lesion, where the 6th nerve runs up and over the clivus. That’s pretty rare. I would submit that you can tell this patient’s diagnosis… Let me just stop the video there… Just by this still photograph. Because what they aren’t doing is they’re concentrating on his eye movements. Which is important. But they are not concentrating on the fellow travelers. Look at his lids. He’s got marked lid retraction and lid lag. When he looks down, look at how wide his left eyelid is open. The right eyelid is retracted a little bit too. But he’s got bilateral lid lag. And let’s watch his lids. Forget about his eye movements. Look at his lid retraction. You don’t need anything more than that to say: This is thyroid eye disease. And he’s got tight medial recti muscles, causing bilateral abduction deficits. Esotropia, double vision. You don’t even need to see his eye movements. This is a diagnosis you should make when you walk in the room and look at his eyelids. Thyroid eye disease. Graves ophthalmopathy. So it can have this red angry look, or this quiet look, we saw her earlier. With lateral superior and inferior lid retraction. And you can see in the lower photo, the left eye appears very exophthalmic, or proptotic. It is. But look at lid retraction. A tumor behind the eye in the orbit — it doesn’t cause retraction. Just proptosis. The combination — my residents will say — wait a minute. Thyroid eye disease? Why is it only one eye? I don’t know. Sometimes it’s only one eye. Same with myasthenia. It’s a systemic condition. It can be one eye. It’s more common to be both. But it can be one.

>> Right straight at me, if you could. Up over your head.

DR GOLNIK: We’ll leave the video sound going.

>> Way to the left. Way to right. Way down. Way up.

DR GOLNIK: Okay. I’m gonna turn the sound off. And let the video run again. So these are her versions. And as I think you heard… I hope you heard… Here she is. Trying to… Look upward. Here’s to the right, here’s to the left, here’s down. There you go. You want to see that again? No eye movements at all. So this is a 75-year-old woman. This has been going on for just two weeks. Just two weeks. Before I saw her, she had been admitted to another hospital and had a bunch of testing. You can imagine what sort of testing she might have. So what’s on the differential for this? Well, certainly myasthenia is. That can cause bilateral ophthalmoplegia. It would be pretty unusual to cause complete bilateral ophthalmoplegia suddenly. But she had a couple of Tensilon tests, acetylcholine receptor tests, of course an MRI. Everything — all of it was negative. They said: Go see Dr. Golnik. We’re gonna discharge you. See what he thinks. Here is her video. The question I asked her is: Is there anything else going on? She said no, not really. I’m fine. My speech is good. I can move my arms and legs. They’re okay. And I said… But anything prior to this happening? What happened? She said… You know, it’s funny. She’s 75. But I’m healthy, you know. I’m really doing very well. But I had this funny gastrointestinal problem a week or two before this started. I hardly ever get something like that. I had diarrhea. It was terrible. For a couple of days. And I said… Okay. I think I know what you’ve got. Maybe some of you know what she has as well. She had what’s been known as the Miller-Fisher variant of Guillain-Barre. These patients have anti-GQ1b antibodies, directed at the intermotor areas of ocular-cranial nerves. It can look like cranial nerve palsies. In her case, it was very striking. They get ophthalmoplegia. She did have some areflexia. Oftentimes it’s postinfectious. Campylobacter is what she had. For some reason this is a common culprit. We told her: We’re gonna treat you with intravenous immunoglobulin. Usually this gets better. She came back in six weeks and said: You lied to me. I am no better. Turning your head. Look up over your head. And you can see her eye movements… And fortunately I had her video from the time before that. Her daughter was also there. And she said: Mom, your eyes are moving much better. But she said: I’m no better! Why did she say that? She said that because she still has a little eso deviation. She wasn’t 100%. Her eyes are still a little esodeviated. So for the patient, that means, sometimes, I’m no better. But clearly she was. Six weeks after this, she came back and said: You’re right. I am better. And her little eso deviation had resolved. So here’s a guy, 56-year-old gentleman. Double vision for just a week. Hypertension. It’s under control. A little asthma. Acuity is good, pupils are good. There was a mild deficit in depression of the right eye. When he looked downward through his bifocal, he developed a little right hypotropia in downgaze only. Hence the symptoms of double vision when reading. Here’s a video. You’ll notice I’m not really concentrating on his eye movements here. And in particular, let’s look at his left upper lid. What happens when he looks from down to up? He looks from down to up. Moves up. Then moves down a bit. And there’s occasionally even a slight little twitch. So this is a Cogan’s lid twitch. We saw one example. This is another example. So as soon as we see this fellow traveler, we say… Ah-ha! Maybe this is myasthenia gravis. And you’ll remember… That the symptoms of myasthenia can include variable and/or fatigable ptosis and double vision. And don’t forget about lagophthalmos. I tell patients the hallmarks of this are: Variability and fatigability. Patients often say: I wake up in the morning, I’m pretty good. Later, not so good. End of the day, terrible. Next morning, cured again. You don’t always get that history, but you might. Beware — sometimes people don’t actually complain about double vision with myasthenia. They might just say it’s blurry. But if you ask about the blur — I’m good with either eye closed. It’s only blurry with both eyes open. They have a mild misalignment that’s not enough for them to call it double vision. Keep in mind I think the caveat is that: Non-myasthenic ptosis, so just senile… Levator dehiscence, old age, that is often worse at the end of the day. Why? Because you’re using your orbicularis — your frontalis muscle to help keep your eyelids open. By the end of the day, it’s tired and you have a little more ptosis. Double vision, if you have a phoria that’s breaking down, it might be worse at the end of the day. Just because they say it’s worse at the end of the day doesn’t mean it’s myasthenia. The question I ask about ptosis is — do you ever have to open one eye to see? No, nothing like that. It just looks a little worse. Nothing that interesting. But if at the end of the day they say I have to hold my eye open to see? That’s very suspicious for myasthenia. Don’t forget. We already talked about eyelid signs. Look for variable ptosis. Sometimes I’ll be talking to the patient, taking the history, and their lid is just bouncing around. It’s a millimeter up, two millimeters down. That’s usually myasthenia. You’re gonna attempt to fatigue them, have them look up at your hand, raise your hand up, and say how long? A minute at most. Your arm will get tired. Look for Cogan’s lid twitch. I showed you a couple of examples of that. And we also checked for orbicularis weakness. Because if there is orbicularis weakness, in the setting of ptosis, and double vision, it’s probably gonna be myasthenia. And then there are motility signs. Of course, as I already mentioned, ocular misalignment can mimic any pattern. I tell my residents, if I show you a patient with double vision, and say: Hey, what do you think? It’s almost always fair game to say… Maybe it’s myasthenia! And remember, the measurements may vary. And I tell my residents — if you go in and make your measurements, and I go in and make measurements, and they’re different, and I say: Oh, man, you’re terrible at this, you can say: Maybe they’ve got myasthenia. So the measurements may vary during your exam. And that would be a sign of possible myasthenia. And it can be unilateral or bilateral, as I’ve mentioned. And you can try to fatigue ophthalmoplegia in myasthenia. This is not a real common finding. But let’s watch a video. Look at his right eye. In the beginning, he’s trying to look all the way to… The left. And watch what happens to the right eye, as time goes by. The video will loop. So here we are, getting towards the end. Look at how much scleral show. His eye is almost back to primary. Watch what happens at the beginning of the video. Which is now. Do you see how much better his adduction is at the beginning? And that right eye just gradually fatigues. And moves back. So I look for this. I can’t tell you this is super common. But it can happen. And of course, that’s why this guy would have very variable measurements. On his misalignment, during the exam. And there is testing. We talked about the ice test already. If you don’t have ice, and they have ptosis, you can do a sleep or also called rest test. They don’t have to go to sleep. If the patient closes their eye, put them in the waiting room. Don’t open your eyes until I tell you. And after 30 minutes, you say: Okay. Open your eyes. Blink once. And look straight ahead. And you can take a photo with your phone these days. Or measure the ptosis before and after. Here’s a fellow with obvious left upper lid ptosis before resting. And here he is after resting. A very positive rest test. And this is my last patient. My last sort of tip for double vision. But really, just for double vision that is intermittent. This guy came in. He’s 55. He says: Yeah, I have double vision once in a while. It doesn’t last very long. A few seconds, maybe a minute at most. Of course, during the exam, his eye movements are full. He has no double vision. He says: I don’t know. There’s really nothing that seems to make it happen. There’s nothing that I do that seems to make it get better. It just comes and goes at will. There’s no pattern. Interestingly, though, he says that when he has the double vision, and when it goes away, he sort of hears or feels a popping kind of sensation. So what do we do with this guy? He’s in your chair. His eyes are normal. I don’t know. Well… These days, probably almost everyone, no matter where you live in the world, perhaps, has a cell phone. Hopefully with a video camera. And so I say… Listen. Your homework is: Take a selfie video. And this video I’m about to show you is just that. So he… Over the weekend, after I saw him, he had it happen. He took a video. He emailed me the video. This is the video. Let’s watch the video. Watch his right eye. And you can see that right eye does not elevate well. Especially when he looks in adduction. Look what’s happening to his right eye. His right eye is pointing downward. Look at that. It’s not as bad when he looks up to the right. But when he looks inward, that right eye goes down. What does he have? I’m sure some of you know. I’m gonna show you the answer. And remember, when it goes away, he sort of senses a popping sensation. So he has a Brown tendon sheath syndrome. His superior oblique muscle is getting caught in his trochlea. So this can be congenital. Obviously in his case, it was not, because this has only been going on for a couple of months. He had rheumatoid arthritis. And a nodule that was causing, in the tendon, in the superior oblique tendon, that area, he was having trouble. That muscle intermittently would get stuck. And when the superior oblique muscle gets stuck in the trochlea, this is what happens. And you can look at the anatomy and figure that out for yourself. So interesting. So we diagnosed him. I called and said: I know for sure what you’ve got. Let’s get a CT scan in this case, and look at that trochlear area, and we found that rheumatoid nodule. So in summary, for a practical approach to the diagnosis of these patients, make sure it’s not monocular. If it is, that’s a whole different story. And do the things we talked about. Check for those fellow travelers. The lids, orbital signs, adjacent cranial nerves. You must determine the pattern of misalignment to get the diagnosis right. And consider myasthenia in every patient with double vision or with ptosis. At least consider it and look for the findings that we’ve talked about. So that’s the first part of this webinar. Well… It’s this webinar. As I said, the first thing they tell my patients, when I see them, in clinic, that double vision — there are always two important questions about double vision. One, what’s going on? Number two, what are we gonna do about it? We need to answer the first question. And this webinar was about answering the first question. The second question is: How are we gonna fix it? What’s the management? And that will be the subject of a second webinar. Okay. I am now going to look at my Q and A here. And if you have questions, feel free to type them in the question and answer box. Here’s a statement more than a question. Some monocular diplopia can be secondary to hypophysis tumors? No, it’s not. I’m not sure how else to say that. It can’t be. How do you examine monocular patients? I don’t. It’s almost always going to be front of the eye. Very rarely an epiretinal membrane, but front of the eye. So you check a pinhole. That should get rid of the double vision. You’re gonna do a careful refraction, careful slit lamp examination, looking at the cornea and at the lens. Please explain double vision in the case of superior oblique palsy. How to manage? So if you determine the patient has a superior oblique palsy, they should have… If it’s a right superior oblique palsy, it should be a right hypertropia. Right? Because the superior oblique muscle has primary action. Is in cyclotorsion. Secondary action is depression. And it’s gonna be a right… So it’ll be a right hypertropia. And that hypertropia will get worse when they look to the left. The opposite side. When the eye is in adduction. And when they tilt their head, to the same side. So when they tilt their head to the right, the misalignment will get worse. When they look to the left, it’ll get worse. And you need to think about the anatomy. If you think about just the anatomy of where the superior oblique muscle inserts on the globe, you can figure that out. Of course, they should have some torsion. And when people have vertical misalignment, and I put the letter up on the chart… And I think it’s a fourth nerve palsy, and I say — hey, I bet you one of those two letters is tilted. It is! Wow, you’re really good. How did you know that? You can measure the torsion with a double Maddox rod. The problem is, a lot of people don’t have double Maddox rod. One of the things you can do, if you don’t, as long as you have a single Maddox rod, you can put up a single Maddox rod and use the eye chart, the horizontal border of the eye chart, as the other Maddox rod. And simply say: Now, you see that with one eye — the non-Maddox rod, you see the border of the eye chart. See how nice and straight that is? Now you see this red line of light with the Maddox rod. Is that line of light parallel to the border of the eye chart? No, it’s not. That would be torsion. You’re not gonna be able to easily measure that. You can do that if you have a trial frame and a Maddox rod, and you can try to measure how many degrees. Typically with a unilateral fourth nerve palsy, you’re gonna have anywhere from a couple degrees to 10, sometimes even more than that. The caveat or the little hint is: If you see more than 10 degrees of that cyclotorsion, think about a bilateral fourth nerve palsy. That would be typically after an injury of some sort. The management depends. A lot of fourth nerve palsies — you know the answer. Because their most common cause is trauma. So then it’s pretty obvious as to what’s causing the problem. And then otherwise, congenital is the next most common. And so… Depending on the story, you may need to get imaging, to make sure nothing else is going on. And the management depends, of course, on the underlying problem. If it’s a mild fourth and fairly comitant, prism can be used. If there’s a lot of torsion, and it’s not improving on its own, as traumatic fourths might, you might need to do strabismus surgery. And just keep in the back of your mind that I’ve seen myasthenia mimic fourth nerve palsy. Looked just like a fourth nerve palsy. And in fact the patient I told you who had the fatigable ptosis — I saw him two years prior to that with what looked like a fourth nerve palsy. He was 60. I said: Oh, this is a microvascular fourth nerve palsy. He had already been imaged. It was normal. I said you’re gonna get better. Sure enough, he came back, completely resolved. I said oh, another great diagnosis. He called me two years later. I’ve got double vision again. But this time my lid is drooping. I said on the phone… Maybe you’ve got a microvascular fourth nerve palsy. And he came in with fourth nerve palsy. I was wrong two years ago. You probably had myasthenia that spontaneously resolved. And now you definitely have myasthenia, based on the findings and the fellow travelers. Let’s see. How to differentiate between monocular and binocular double vision? It should be fairly simple. Oftentimes, patients may not know. Just look at the letter on the chart. Is it double? Yes. Close your left eye. Is it still double? No. Close your right eye. Is it still double? No. Open both eyes. Is it double? You have binocular double vision. Now, the problem is: Once in a while, someone has both. And they’ll say… Yeah, I see two images. When I close one eye, one of them goes away. I close the other eye… When I look with one eye, it’s still kind of ghosting. They have both binocular and monocular double vision. Someone answered that, it looked like. Important checks to differentiate (muttering) right. The first step is what we just talked about. You have to determine the diagnosis. Make sure we’ve got the right diagnosis. We talked about a lot of different entities today. Some of which are neurologic, some of which are not. The sagging eye syndrome is not. How do we know they have the sagging eye syndrome? It’s usually based on the history, the measurements, and in those patients, if they have the classic story, like the patient I showed, I don’t image them. I repeat their measurements. (audio drop) and if they are, we usually treat them with prism. They’re very happy, usually, with prism. What else can I say about that? I mean, of course if they have the pattern of a cranial nerve palsy, and most double vision is — binocular double vision is neurologic, as opposed to ophthalmologic… I just mentioned that. And almost always the measurements are pretty small. The misalignments are fairly comitant, and prism works great. Rarely is there so much misalignment that they’ll need strabismus surgery. The cause of Cogan’s lid twitch? I don’t know. It’s an interesting question. No one’s ever asked me that. I don’t know. It must have something to do with just the fatigability, rapid fatigability, trying to correct it. I really don’t know the cause. How can we confirm from a child about double vision or blurred vision? You’ve got to do your cover-uncover test and cross-cover testing. I definitely have adults who say: No, it’s not doubled, but it’s blurry. And they obviously have misalignment, and they just will not appreciate it as double. But… As soon as you cover either eye, they’ll say — oh, the blur goes away. The kid should be the same. So… The kid will blurry vision, you’ve got to… They have to be able to focus on a target. If it’s a really little kid, they’re not gonna be complaining of anything, and then Hirschberg is all you’ve got. But in a kid or an adult, to distinguish between the two, you have to do your cover-uncover testing. Brown tendon sheath syndrome is like Brown syndrome? Yes, most of the time it’s a congenital problem. It’s a developmental problem. Where you just don’t get a good separation between the tendon and the trochlea. And that requires surgery. Fairly minor surgery. In the setting of the fellow I showed, who has the most common cause of an acquired Brown syndrome, that is a rheumatoid arthritis, you treat the rheumatoid arthritis. You could possibly do steroid injections, if the systemic treatment doesn’t work. It could be treated surgically, if need be. Probably trauma is another cause that could happen, and you wait and see, and if it doesn’t get better, you could do surgery. The role of Hess testing? So Hess screen is something that my neuro-ophthalmologist mentor, when I was a resident, we used the Hess screen a lot. I don’t have a Hess screen. I don’t use the Hess screen. I think it certainly can be helpful for diagnosing patterns of misalignment. If you have a Hess screen. I would venture to say that the vast majority of ophthalmologists in the world don’t have a Hess screen. I find that I can very quickly, with cover-uncover testing and prisms, determine the pattern of misalignment. You don’t need a Hess screen. So honestly, I don’t use one. Can dry eye syndrome be a cause of monocular double vision? Definitely. As I tell patients, especially intermittent monocular double vision. I tell patients that the cornea-tear interface is responsible for 2/3 of the focusing power of your eye. So if you have dry eyes, definitely can cause monocular double vision. What can be the differential if a one and a half syndrome resolves in one day? In one day. A one and a half syndrome. We didn’t show a video of that. I’ve got some. Is when you have an INO, so a right INO, so your right eye does not adduct fully. And you also have a gaze palsy on the right. So neither eye moves to the right. So the only motion is abduction of the left eye. That’s a one and a half. So one and a half syndrome is almost always due to a small infarct in the pons that affects the MLF. And the horizontal gaze center. So a TIA, transient ischemic attack, because if there is ischemia that resolves in one day, by definition, that’s a TIA… A TIA… An ischemic… Well, TIA… That’s redundant. A transient ischemic attack could resolve in one day. Now, the other thing that could look like a one and a half — remember — is myasthenia. Myasthenia can mimic anything. It could resolve in one day. It would be unlikely, but I think if you saw someone who you were convinced had a one and a half syndrome acutely resolving in one day, I would treat that as a transient ischemic attack, and make sure risk factors were looked at, and so on. Ptosis due to multiple sclerosis, is there an ice test? On the study we reported on ice tests, we looked at ptosis from a variety of other causes and looked at ice testing and it did not improve in any of the other patients. Can you give some tips on diagnosing accommodative spasm? That’s a tough problem. The tips on diagnosing it are a lot easier than tips on fixing it. The tips on diagnosing it are… In accommodative spasm, basically the patient is stuck either constantly or transiently in accommodation. Really the near reflex. And so they’re myopic, because they’re stuck… Their accommodation is stuck. But they’re esotropic. So the convergence is stuck. And the important way to make that diagnosis — one of them — is: Look at the pupils. Because the pupils will get small. So when that person is stuck in accommodation, and that near reflex, there will be miosis. So if the person is having this intermittent esotropia, and it’s normal then huge esotropia, look at those pupils, and you’ll see miosis of the pupils. They can also have what are called pseudoabduction deficits. Sometimes this happens just in young people who are nervous. I say follow my finger. And all of a sudden their eyes start crossing. Their abducting eye. You just keep them out there and usually the abducting eye will move out. I’ve got videos of that too. But can’t pull them up probably fast enough to show you. Look at the pupils. That’s probably the best tip. Hess test — we answered that already. So management of double vision. So management of double vision, of course, if you have the Hess screen, you can follow the Hess screen for improvement. So that’s the other way. I just do prism measurements. How can you identify fourth nerve palsy with both third and fourth? Good question. I debated on showing that in my videos. So in a complete third nerve — if they’ve got a mild third, it’s virtually impossible. But if they have a complete third nerve palsy, what you do is — and you’re checking for the fourth nerve function — you have the patient look, you ascertain — oh, that right eye doesn’t move up or down or in. You have them then look up, or try to look up, and then down. And what will happen if the fourth nerve is working: The eye in question will intort. It won’t really move up and down at all. But it will intort. Remember, the primary action of the superior oblique muscle is intorsion. So you look the nasal conjunctival vessels, and you’ll see a nice intorsion of the eye. If you don’t see intorsion in a complete third, when you have them look from up to down, they also have a fourth. And now you’ve got a different story. You’ve got a third and a fourth. If the patient has different variable degree of diplopia can we prescribe prism? Well, so that’s the big problem. And that’s why patients with myasthenia, who often have very variable double vision, why prism usually doesn’t work very well. Of course, near does eye muscle surgery. So hopefully we can treat them with medications. The other problem — so I tell patients there are two big limitations of prism. Well, three. One: If it’s a really big misalignment, it’s gonna be tough to make you happy with prism. And by really big, I mean more than 15. Two, if it’s very incomitant, then prism — you can put the right amount of prism for primary, but as soon as they look just a little left or a little right, they’re gonna have double vision. They’re just gonna close one eye. And then of course, where they truly are variable, like myasthenia, it’s a moving target. How do we detect double vision due to skew deviation? So skew deviation, by definition, is a vertical misalignment of the eyes. Due to asymmetric input to the vertical gaze sense. So it doesn’t… It’s not gonna look like a third nerve. It’s not gonna look like a fourth nerve. They typically have full ductions and versions, because it is a supranuclear problem. It may be comitant. It may be incomitant. One of the tricks is: You can look at the misalignment in upright position and in lying down position. And in lying down position, the skew can improve. But that can be a tough choice. And that’s sometimes why we get MRIs, to look. To see if we see any lesions in the brain stem/cerebellum. Because it’s a pretty non-specific sort of a finding. How often is binocular double vision an ophthalmic emergency? Almost never. Certainly we all know and we didn’t talk, but we all know about an aneurysmal third nerve palsy. That’s an emergency. That person needs imaging. They need an MRA. MRI. Or CTA. You need the A to look for aneurysms at the blood vessels. You have to have the A. An MRI is not sufficient. You need an A. MRA or CTA. That is an emergency. Otherwise, the ophthalmic emergencies… I mean, certainly if someone is having a big stroke and they have hemiparesis, that will be pretty obvious. But if it’s isolated double vision — don’t forget carotid dissections. They can cause double vision. Typically we think about Horner syndrome. But most of the time binocular double vision, unless it’s a third nerve palsy, is not an emergency. I’d like more information on sagging eye. Perhaps this is for further lectures. I do have a further lecture. Sagging eye, heavy eye, myopia. There is something I didn’t mention called the heavy eye syndrome in high myopia. That should be fairly easy to distinguish. Because they’re usually high myopes. But it is a topic for something else. You know, there are definitely references that you can read up on, on the difference. Probably don’t have enough time to really go through all of it right now. What are the differentials of binocular double vision in a child? Well, all the same things as in an adult, plus… Well, in a child, you know, most kids with double vision suppress. They subconsciously ignore an image. So double vision is not as common in a child. And someone had asked earlier — you know, sometimes kids don’t complain of double vision. Because they’re suppressing one of the images. And that’s how you get strabismic amblyopia. They ignore the other image and they don’t develop double vision in the eye. I think the differentials are: They don’t include things like sagging eye syndrome, for instance, but certainly double vision in a kid, you have to think about all the same things. Tumors. I mean, you’ve got the postviral sixth nerve palsies, which are usually benign. But a kid with double vision is gonna get an MRI, with and without dye. Almost — unless you know for sure what’s causing the problem already. When do you order neuroimaging in a patient with double vision? Unless you are sure the problem is congenital, like a congenital fourth, or you’re sure that it’s sagging eye syndrome, or you know they had a head injury… Well, they’ve probably already been imaged, if they had a head injury. Then you’re probably gonna get imaging. And again, MRI is just way better than CAT scans. And now we’re running out of time here. I told everyone I would be done by 10:15. Let’s see. (inaudible) persistent postoperative double vision after strabismus surgery. Don’t ask me. I don’t do strabismus surgery. But prism, probably. Second surgery. A patient has double vision that disappears when he uses spectacles. What could that be? If it’s monocular, it explains it. It may be that he’s just got much better vision, he has a phoria, he can control it. Is double vision common and obvious in computer syndrome, especially children? I don’t know. And I don’t see kids. We have a pediatric neuro-ophthalmologist for that. Medical management for myasthenia? Yes, there is. That will be the topic of the next webinar that I mentioned. Yeah, we could ask my colleague, the pediatric ophthalmologist, to do a talk on that. For Orbis. And thanks, Rita. Greetings from Cincinnati. Do you order MRI in every sagging eye? I never order an MRI in anybody who I think has sagging eye. What is the highest power of prism? Well, it probably depends a little bit on the patient. I think more than 15… I mean, you can use Fresnel press-on prisms at higher, but people usually don’t like them very much. I’m gonna skip this one about the patient. Sensitivity of ice test. So in our paper, we had 20 patients. With known myasthenia, because they had positive blood tests. So we had to have a gold standard. That was our gold standard. They all of course had ptosis. You can’t do an ice test without ptosis. Of the 20 patients, 16 had a positive ice test. Now, the thing I didn’t mention but should is that three of the four patients who had a negative ice test had complete ptosis. Complete. So in the setting of complete ptosis, the ice test may not be helpful. However, what else is it gonna be, right? You’ve got a complete ptosis, you’ve got either complete third nerve palsy, which should be pretty obvious on the exam, or you’ve got myasthenia. So in the setting of complete ptosis, the sensitivity is very low. In the setting of incomplete ptosis, 16 of 17 patients had a positive ice test. Let’s see. It’s 10:16. I’m scrolling through. Sorry. I’ve got a lot of questions about kids. Which I’m not gonna answer. Double vision after laser refractive surgery? Something to do with the cornea! It’s refractive. Multiple sclerosis and double vision? For sure. Second most common. Optic neuritis obviously the most common. Double vision, second most common reason I see a patient with MS. It can cause skew deviations. It can cause 3rd or 4th or 6th. How should I use ice tests? Two minutes long. Oh, one last question. Just because it’s important. What does it mean when we say monocular double vision could be unilateral or bilateral? It means you can have monocular double vision in one eye only. Let’s say you have dry eye on the left. Or it could be in both eyes. You have double vision in both eyes, because you have dry eyes in both eyes. The point is it’s still there if you cover one eye. It’s monocular. It can be in both eyes, but it’s there when you cover either eye. That’s monocular. That’s bilateral monocular. All right. I’m gonna say so long. We went a little bit over time. Thanks, everybody. We’ll work on scheduling the second webinar on sort of the treatments, the approach to these patients. Once you know what they have, how do we answer that second question of: What do we do about the problem? Have a great day.