Special Series: Phenomenology of Chorea

So I'd like to start off with just the basic phenomenology. I know this is a little challenging without videos, but since this is a n auditory [00:01:00] podcast. How would you describe the appearance of chorea?

[00:01:04] Prof. Joseph Jankovic: So thank you, Ruth, for giving me the opportunity to talk to you about chorea, which is one of my favorite topics. In fact, it's a topic that I cover in our ASPEN course, which, as you know, is our annual course. This is going to be our 34th year in ASPEN covering All aspects of movement disorders, hypokinetic and hyperkinetic.

So the topic that I assigned myself when we started the course 34 years ago was chorea, among other topics. And so when we talk about chorea, we're talking about hyperkinetic movement disorder. Which is characterized by involuntary, continuous, abrupt, rapid, brief, unsustained, jerky, irregular movements that flow randomly from one body part to another.

And notice I emphasize the word [00:02:00] randomly because that I think is the key phenomenological feature that allows us to differentiate this particular hyperkinetic disorder from some other hyperkinetic disorder. So it's the random nature of these jerk like movements that helps us recognize chorea as a unique hyperkinetic disorder.

[00:02:21] Dr. Ruth Walker: Thank you. That's perfect. So, are there any other particular features of the, the movement disorder itself that you specifically look for when you start to kind of observe the patient with chorea. 

[00:02:31] Prof. Joseph Jankovic: Well I'm typically the, you know, patients with chorea, they may not even recognize themselves that they have this involuntary movement. But it's recognized often by the family members, particularly in a setting of Huntington's disease as a sort of a, a restless jerk like movement that may involved any part of the body.

So they involve a face patients have sort of, twitchy, jerky type movements in the [00:03:00] face. One of the characteristic features associated with Huntington's disease is that at the onset many of them have sort of a narrowing of the pupillary fissure. So they have a sort of intermittent partial closure of their eyes.

And that may be actually one of the earliest features of facial Chorea in patients with Huntington's disease. They also at the beginning have what you refer to as perikinesia. So they are trying to camouflage the chorea by semi purposeful movements. So they, for example, touch their face or adjust their glasses.

And that often delays the recognition of chorea. When they walk they often have sort of an irregular dance like gait when we examine them what we look for is not only these jerk-like random movements but other features that are typically associated with chorea, such as hung up reflexes and pendulum reflexes and also motor impersistence so the patients may have [00:04:00] Inability to maintain tongue protrusion.

They have this so-called darting tongue phenomena or they have trouble maintaining grip on examiners fingers. So they have what is often referred to as milk maid's grip. The later is more typically seen in Sondheim chorea than than Huntington disease. So these are some of the, the features of, chorea.

You know, many people think that chorea is just a restless, perhaps embarrassing woman. But actually it can be quite troublesome and in many cases, you know, disabling. I remember when we first applied for tetrabenazine approval for chorea associated Huntington's disease, when we were in front of the FDA panel Rusty Katz, who was at the time the director of the neurologic division of FDA say, well, what difference does it make with the patients have chorea or not?

And so I tried to explain to him that chorea is not just a cosmetic problem, but can interfere with fine and the gross motor coordination. [00:05:00] And it can increase problems with balance cause falls and cause severe, morbidity and even, you know, mortality and but we had to do additional studies to demonstrate that chorea actually interferes with quality of life and activities of daily living. 

[00:05:17] Dr. Ruth Walker: You're already anticipated a number of my questions, I was going to askyou about the degree to which chorea interferes with volitional movements. I mean certainly, in my experience when it's relatively mild, people can still kind of do, finger to nose testing and things like that fairly well. But obviously not when it's more, more severe.

Is that basically your experience as well?

[00:05:39] Prof. Joseph Jankovic: Yes, absolutely. You know, again, the one of the characteristics of chorea, particularly in the setting of Huntington disease is the sort of the lack of awareness that patients have, you know, that about their involuntary movements. They may maybe perceive it a little bit as sort of a feeling of restlessness. It's not [00:06:00] until the chorea begins to interfere with their voluntary movements and with activities of daily living that finally they seek, you know, medical attention.

[00:06:09] Dr. Ruth Walker: How would you describe the difference between chorea and dystonia? Just because sometimes people can be confused about the difference between the two hyperkinetic disorders.

[00:06:21] Prof. Joseph Jankovic: Well, there really shouldn't be any confusion between those two hyperkinetic disorders as I emphasized at the beginning. The characteristic feature , of chorea is the randomness of these jerk-like movements whereas in dystonia, it's exactly the opposite. The movements are patterned, sustained, meaning the same group of muscles is always involved. So for example, a patient with dystonia who has involvement of the neck, the cervical dystonia or torticollis, they will always have turning of the head to the same side. It's not like they would turn their head to the right side and next arm to the left side. It just doesn't happen. [00:07:00] You know, if it does happen, then you start thinking about functional, psychogenic, dystonia.

So you know, there really shouldn't be much confusion, although I should point out that patients with dystonia sometimes have jerk like, movement that may superficially resemble chorea. But again, the movement in dystonia is always patterned, meaning the same group of muscles is involved as opposed to the jerk like movements in chorea, which are random. 

[00:07:28] Dr. Ruth Walker: Absolutely. I've seen a couple of people where they had what turned out to be really multifocal myoclonus, very small amplitude, but multifocal jerks. And it was kind of confusing as to whether they, you know, which movement disorder they had. have you come across people like that and how might you distinguish myoclonus from chorea?

[00:07:48] Prof. Joseph Jankovic: Right. So both the myoclonus and Chorea are sort of jerk like movements. And I agree that sometimes multifocal myoclonus can look [00:08:00] like Chorea. One of the helpful differentiating features is that Chorea tends to be a more continuous movement. It's there all the time. It moves , you know, randomly from one body part to another, but it's there all the time, whereas myoclonus is is manifested by these jerk like movements which are separated by silence. So it's not a continuous movement that we see with chorea.

[00:08:25] Dr. Ruth Walker: Thank you. that's a really helpful observation. What about action, versus rest? Do you feel like when people, Make other movements if that brings out chorea. Do you tend to see the, you know, the movement disorder more when someone's relaxed at rest? What do you think about that?

[00:08:44] Prof. Joseph Jankovic: Yeah, just like other hyperkinetic disorders, Korea tends to be, you know, more prominent when they are moving like, for example, patients with Huntington, when they are sitting and particularly in the early stages, may have minimal, very [00:09:00] perceptible chorea, but when they start walking you can see the correct movements not only in their Gate manifested by this irregular dance like movement, but also in their face and in their fingers.

So voluntary movement can also often bring out chorea.

[00:09:19] Dr. Ruth Walker: Right, right. Now, I want to ask you about a couple of other terms we use for hyperkinetic disorders. So one of them is bolism. We often talk about hemibolism, Is this, do you think that this is the same thing as chorea?

[00:09:36] Prof. Joseph Jankovic: Well, to some degree I think there is a similarity and one way to sort of support this notion that there is some similarity between hemibolism or bolism and chorea is that one of these movement disorders can evolve into another. So typically for example, when we see patients with a stroke related Hemibolism which may involve the contralateral [00:10:00] subthalamic nucleus or some other parts of the brain.

Initially the movements may be very violent high amplitude type movements more proximal than distal. And that is the characteristic feature of hemibolism, but as the condition evolves these movements become lower in amplitude and become, a little bit more random and resemble, chorea.

So bolism often involves into Korea. And you, We're probably going to ask me a little bit about athetosis, which is another hyperkinetic disorder that is sometimes confused with chorea. And there's a term ptosis, which actually I don't like that term at all. But basically what we talk about with respect to athetosis is it's a form of slow chorea.

So if take somebody with that chorea and you played that video in slow motion. You get this sort of a slow, writhing [00:11:00] type movements which are again, somewhat irregular and random but are slower less jerk like than what we see in chorea. So again, one can evolve into another. So I, I think as movement disorder phenomenologists.

We should really commit ourselves into making a diagnosis of either chorea or athetosis and not take the easy path by calling it choreoathetosis. So that's my main objection to the term choreoathetosis. In most cases you can differentiate it to chorea or athetosis.

[00:11:37] Dr. Ruth Walker: Absolutely, you're absolutely right, that was going to be my next question. You mentioned a little bit about the narrowing of the palpable fissure, particularly in Huntington's disease, and I think that's just like a really, a valuable observation. What about if you see somebody with a lot more, kind of lower facial, h ypokinetic movements rather than the upper face. Is [00:12:00] this something which is a useful diagnostic feature?

[00:12:04] Prof. Joseph Jankovic: Yeah. So there is often confusion about the hyper movement that is seen in patients, let's say with tardive dyskinesia and Huntington's disease. So in tardive dyskinesia, obviously typically we see this orofacial lingual movement, which is really not. random. If you really closely analyze that movement, it's more predictable, more stereotypic.

And in fact in most cases of tardive or facial dyskinesia, what we see is a stereotopy, not really chorea. And in fact, tardive chorea, in my opinion, is extremely rare. Most tardive hyperkinetic disorders are manifested by stereotopy. Occasionally you can see tick like movements, maybe even chorea.

We describe tardive tremor but tardive chorea actually is very, very rare. And yet many [00:13:00] times, particularly psychiatrists, you know may describe tardive syndrome and patients taking neuroleptics as chorea, but it's really not chorea. It's almost always stereotopy.

[00:13:13] Dr. Ruth Walker: The, the whole entity of tardive movement disorders is really inadequately described, but that's a really interesting observation. And suddenly I would like to get away from the term tardive dyskinesia, apart from as a Diagnostic category, but not as certainly it's not very useful in terms of phenomenology.

Do you think people with chorea, when they're aware of the movements, are they able to suppress the movements ever?

[00:13:40] Prof. Joseph Jankovic: Yeah, it's an interesting question. So in patients with Huntington's disease which is sort of the typical condition in which chorea occurs when they are asked to suppress the involuntary movement and relatively cognitively intact they may partially suppress it, but they, they rarely can suppress it completely.[00:14:00] 

On the other hand when we see chorea. In other conditions for example, in certain autoimmune disorders or perineoplastic disorders I find that chorea can be suppressible. And I often show a video in Aspen of a patient with perineoplastic syndrome with the autoimmune antibodies because of underlying lung cancer.

Who presented with chorea and superficially you would not be able to differentiate a patient from Huntington's disease in as chorea. But interestingly, when I asked him to suppress the chorea, he was able to do that, completely for a few seconds. So I found that quite interesting and perhaps helpful in distinguishing chorea associated, let's say, with Huntington's disease versus autoimmune chorea.

[00:14:49] Dr. Ruth Walker: That's interesting. Yeah, I have found that people sometimes can suppress the movement. So I did have one guy with what I thought was chorea and actually turned out to be tics. It was really [00:15:00] multifocal movements. And what he said was, when I make a movement on one side, I have to make it on the other.

So I was like, aha, this is, this is tics, not, not choreo. so...,

[00:15:08] Prof. Joseph Jankovic: yeah, I'm glad that you, you mentioned tics because obviously one of the characteristic features of tics is that they are suppressible. But a few years ago, maybe actually a few decades ago we described a family. Of individuals who had adult onset Tourettetism. So they started with tics motor tics and phonic tic s, including coprolalia, and they had basically classic Tourette's syndrome.

The only atypical feature was that they were of adult onset in their thirties and forties. And as we follow these and we suspected that they probably don't have Tourette syndrome because of the age of onset. As we followed these patients they eventually developed in addition to the tics Chorea, and it turned out that they had Huntington's disease.

So we reported that family as [00:16:00] adult onset Tourettetism as the presenting feature of Huntington's disease. But it's an example of a condition where both chorea and tics can coexist.

[00:16:10] Dr. Ruth Walker: Yeah, certainly in a lot of these neurodegenerative disorders, people can have mixed phenomenology and that's obviously something to important to bear in mind. Do you think there's any role for electrophysiology in the diagnosis of chorea?

[00:16:26] Prof. Joseph Jankovic: Well, as you know, I'm a phenomenologist, not neurophysiologist. If you ask that question to Mark Hallett or some other neurophysiologist, they would obviously say that neurophysiology, can be very helpful. I think if you need EMG or the neurophysiological Test to make a diagnosis of chorea.

I think you're in big trouble. You know, that diagnosis should not be made by EMG or neurophysiological tests. Having said it you know, neurophysiology can be helpful in studying different forms of chorea. For example Mark Hallett and [00:17:00] others show that the EMG contraction, for example, in patients with Sondheim chorea, maybe a little bit longer than in Huntington's.

So in that regard you know neurophysiology may be helpful in differentiating chorea due to, let's Sondheim chorea versus, Huntington's disease. But again, I think if you have to use neurophysiology to make a diagnosis of chorea, I think you are in trouble.

[00:17:27] Dr. Ruth Walker: Yes. Thank you. So I've got one other question, I think. And I just wanted to ask you about chorea of the tongue, sometimes I'm looking at somebody and it's like, is this dystonia? Is this, is this chorea? And the tongue kind of has a limited range of, movements and, directions in which it can go.

Any comments on, chorea of the tongue?

[00:17:50] Prof. Joseph Jankovic: Yeah, it's a, it's a interesting question. So many clinicians, including experienced clinicians, when they examine the tongue they ask [00:18:00] patients to protrude the tongue right away. That's not the best way to examine the tongue. So the first thing that I do when I want to examine the tongue is observe the patient without even opening the mouth to see if I see any kind of movements in their mouth that may suggest that there may be underlying tongue movement.

And then I ask the patient to open the mouth, but not. Protrude a tongue and see what happens, you know, with a tongue. When it's just resting when the mouth is open and what you typically see in for example in patients with tardive dyskinesia is a sort of a repetitive coordinated type movement of the tongue. Again, suggesting stereotopy as opposed to chorea of the tongue, which is more sort of a regular random type movement.

Now, when you ask the patient to protrude the tongue. As I mentioned before, patients with with Huntington's disease they have trouble maintaining the tongue protrusion and they have sort of a, what is referred to [00:19:00] as a darting tongue type phenomena that actually is not a form of chorea that is a form of Impersistence.

It's a frontal lobe dysfunction. So they have trouble maintaining contraction in this case, maintaining tongue protrusion. And that's the reason why the tongue seems to be moving in and out of the mouth. So that by itself really is not a form of chorea that is basically a motor impersistence.

Was patients without a tardive dyskinesia. They continue to have the involuntary movement. And in many cases patients with tardive dyskinesia they say that the tongue is irritating or is being irritated by their teeth because it's pushing against the teeth. And sometimes it pushes the food out of their mouth and the tongue actually involuntary.

Protrudes out of their mouth. That is not commonly seen in Huntington's disease. They, they usually don't have involuntary tongue protrusion.

[00:19:59] Dr. Ruth Walker: Hey, thank you. We [00:20:00] obviously we could talk all day about chorea. But I think you've covered all of the key points I wanted to ask you about today. And we really appreciate all of your comments on the phenomenology of chorea., thank you so much for your time. And I'll wish you all the best for your day. Thank you so much, Joe. Really appreciate it.

[00:20:20] Prof. Joseph Jankovic: Thank you, Ruth. Nice talking to you.

[00:20:22] Dr. Ruth Walker: You too. Take care.