Search for tag: "essential tremor"

Interviewer: We're here with Dr. John Rolston, the Director of Functional Neurosurgery, and Dr. Matthew Alexander, he's an Assistant Professor of Radiology and Neurosurgery here at University of Utah Health. Let's start with just kind of talking about essential tremors. What is an essential tremor and what does that mean for patients that have it?

Dr. Rolston: So essential tremor is the most common movement disorder that anyone in the world has. So it's a movement disorder characterized by uncontrolled tremors or movements of typically the hands, but sometimes the voice and head too. These movements are pretty common around eight times per second when they happen, and they can start disrupting people's lives. So with a really bad tremor, it's hard to do things like sign your name, write checks, hard to eat or drink from a glass, hard to eat soup with a spoon. It can become so disabling that people are unable to do these activities at all. And that's when they start to, and before them, when they start to approach us for medical treatment or surgical treatment.

Interviewer: And so you're saying eight times a second? Is that all day long?

Dr. Rolston: All day long, all the time, except when you're asleep when it goes away. But when you're doing any sort of activity, it's there and prevents you from doing all these normal things you used to do like talk on the phone or type on a keyboard.

Interviewer: And what causes it?

Dr. Rolston: We don't really know yet. So even though it's the most common movement disorder, the amount of research that's been done for it is far dwarfed by the amount that's been done with other diseases like Parkinson's. So we're still trying to find out the underlying mechanisms for what causes it. But we do know that it's definitely involving circuits in the brain. We know this because changing how these circuits function can improve the tremor, which is the basis of our surgical therapies for a tremor.

Interviewer: And Dr. Alexander, when someone comes with an essential tremor, how do you diagnose it? What do you look for? What do you . . .

Dr. Alexander: So it's fairly obvious to us by the time they get to us, but it's usually a progressive disease that has gone over the course of decades. There can be familial variants. So some people experience this starting their 20s, 30s. I've heard of some people even in their teens. Most people, it's, you know, middle-aged folks start to notice it. And it's usually just kind of a tremor that they have in their hands. They might notice it gets a little worse with intentional movements. But it's a progressive disease. And so they'll notice over years that it gets worse and worse and worse. And so by the time they get to us, because we only treat the most advanced cases, it's a pretty easy diagnosis to make. And it's often been made by someone in the community, either a primary care physician or someone in neurology that that patient has been referred to.

Interviewer: And Dr. Rolston, after you have the diagnosis, you're seeing these people, they have this really debilitating tremor in their lives, what is the way that it's typically treated or used to be treated?

Dr. Rolston: Sure, that's a great question. So the way we typically start treating these patients is with medications. So there's only one FDA-approved medication for essential tremor, and that's propranolol. The brand name is Inderal. So many patients are prescribed this if they can tolerate it, if they're not forced out by the side effects of low pulse, dizziness, lightheadedness. Then, they can go and take this medication, and it might reduce the either frequency of the tremor or the amplitude of the tremor, so basically how much it's affecting them.

There's other drugs when that one doesn't work. There's another drug called Primidone, which is very common. It's actually an anti-seizure drug. This one also has a lot of side effects, so dizziness, tiredness, that a lot of people can't tolerate. Once those two medications have failed, there's a lot of other more experimental drugs people try. But when the first two primary drugs fail, the chances of one of these third or fourth-line therapies working is pretty low. And that's when surgical therapy becomes more of an indication.

Interviewer: What is the typical way of doing the surgery? I mean, we're talking brain surgery, right?

Dr. Rolston: Yeah. So they've known since the 1950s that if you go to these small little parts inside the brain . . . they're called the ventral intermediate nuclei of the thalamus. So there's two of these. They're both pea-sized little pieces of tissue deep inside the brain, kind of toward the middle of the brain. There's one on the left and one on the right.

If we damage either one of these . . . We noticed, back in the '50s again, that there was a substantial improvement in the tremor on the opposite side of the body. So if you injure or get rid of this left-sided one, you can see an improvement in the tremor on the right side and vice versa. The way we used to do that was with an open brain surgeries. We would make a hole in the skull, insert a fine needle, heat up the tip of the needle, and burn out this small little pea-sized area. This worked great, but it involves a hole in the head, which is a big deterrent for a lot of people to seek this therapy.

Interviewer: Understandably.

Dr. Rolston: Yeah. In the 1990s, they developed a deep brain stimulation, which puts a wire in the same location, but instead of damaging that part of the brain, it stimulates it electrically with a pacemaker that sits in the chest. And that's very effective. And that's what we've been mostly doing for the past couple of decades now.

Interviewer: But it's my understanding there's this new ultrasound-assisted . . . what is it called?

Dr. Alexander: MR-guided focused ultrasound. The MR is for magnetic resonance, so like an MRI machine, which is actually where we perform the surgery.

Interviewer: Inside the big tube?

Dr. Alexander: Yes.

Interviewer: Wow. Okay.

Dr. Alexander: So they go in an even smaller tube, the thing goes inside that big tube. So this utilizes the opportunity of ultrasound to be able to deliver energy to tissues in the body. So we normally think of ultrasound when it comes to diagnostic imaging, so maybe for like an obstetrical ultrasound, to look at a fetus, or maybe if somebody has gallstones, they look at the gallbladder that way. And that involves a diverging set of little sound waves that are sent out from a probe. And then, that bounces back and gets interpreted and spit out by a computer on a screen to look at an image inside the body.

We've known for a long time that each of those little sound waves can cause a little bit of energy to be deposited in the tissues. In those diagnostic scenarios, it's very safe. Again, they're diverging and it's a small amount of energy. We know that we can focus these beams much like using a magnifying glass with the sunlight. And we can use that to actually effect change. We deposit enough energy that we raise the temperature and burn that little pea-sized area just as they did back in the '50s but without actually making an incision.

Ultrasound, it's the same technology that underlies those imaging studies that people get, but it's a different way to harness that energy to use over 1,000 elements to deliver a bunch of very small things. And so you get them all converged at one area. It actually delivers a fair amount of energy. And so we go through several steps of imaging to map out where this VIM nucleus of the thalamus is using an MRI. And then, we also have a CT scan that kind of maps the skull, and then we overlay that with the MRI. And using that CT of the skull, we can direct the ultrasound to make sure that we target it precisely where we need to get.

Interviewer: Wow. And how long does the whole process take?

Dr. Alexander: So the whole process is probably about three to four hours. Part of that is spent shaving the head, getting the frame on. The actual part where they're in the scanner is probably anywhere from an hour and a half to three hours. Probably more often on the hour-and-a-half range though at this point.

Interviewer: And then what? Do you just send them home? Are they stuck in the hospital for a while or . . .

Dr. Alexander: We observe them for a little bit, make sure there are no side effects. They've gotten some of those medications. And then, there will be a little bit of swelling in the brain that makes them a little uneasy, a little wobbly. So we observe them for an hour or two, but it's an outpatient procedure. They go home that day.

Interviewer: Dr. Rolston, how long have you guys been doing this?

Dr. Rolston: So we've been doing this for about a year now. It's been FDA-approved for slightly longer than that. So we're the only place that does it in this time zone in the United States, so the only center in this region. We've had a great experience. So the patients that we've done have had fantastic outcomes.

When they did the randomized control trial to prove that this was effective, they had about, on average, a 50% improvement in the tremor. But that included patients that . . . The way they designed the study was called an intention to treat. So there were some people that didn't actually get treated that are included in that 50%. So the results, they were probably a little bit better than that. We're seeing results that are better than that still. So more like 75% or better improvement in the tremor for all the patients we've treated.

There's some thoughts and considerations we put into selecting patients. We want to make sure that they obviously have essential tremor before we do this procedure. But there's also a consideration for how dense the skull is. The skull is a big component of how we do the therapy. We try to do the therapy through the skull with the ultrasound, but sound waves travel really well through solid, dense things, but less well through kind of mushy, less solid things. So you can kind of imagine knocking on a table, and that has a nice loud echo, but if you knock on a pillow, you don't get much sound through that.

So we need to make sure the patient's skull is very dense and able to conduct these sound waves to cause the changes we're looking for. And we do this with a preoperative CT. So we get a CT scan the day before or a month before. And we measure the density of the skull to make sure that we can actually have a successful therapy. And there's some people, especially with bad osteoporosis, where we can't get the result we're looking for. So those patients, you could perform the procedure, but you might not get enough temperature increase to cause a permanent change.

The most important thing about this is we've had good surgical treatments for tremor for a long time, but many people are understandably worried about doing any invasive surgery, any sort of incision anywhere. Now that we have this non-invasive treatment, even though there are some limitations based upon skull density, some limitations on the kind of person to be best for, even though we have that, it's a wonderful new opportunity to bring people in for a treatment that otherwise would never consider any sort of invasive therapy. So there's a large population of patients that would never be able to be treated that can now be treated, which is why we have such a tremendous response to this and so many patients that are interested.

Interviewer: This seems like a technology that could be used in a lot of potential ways. What do you think the future is for this?

Dr. Alexander: Absolutely.

Dr. Rolston: Yeah.

Dr. Alexander: So it's a fantastic new tool, and we're looking for ways to apply this tool. So there are new trials that are currently underway for other things such as Parkinson's disease, mood disorders, things like that that will be on the horizon in the coming years. But then, in addition to that, and part of what's exciting to be doing this at the University of Utah, is we're looking to further expand indications. So we are working with some of our basic science and translational researchers here on campus to use animal models to try to develop new methods, new things that we can use this to tackle. And so it's a really exciting opportunity, both to be able to offer this new, really effective treatment, but also be able to try to expand the horizons so that we could offer it for, you know, a lot more people for a lot different diseases.

Dr. Miller: You have a tremor in your hand. What's that all about? This is Dr. Tom Miller here today to tell you about that on Scope Radio.

Hi, I'm here with Dr. Lauren Schrock. She's an assistant professor of neurology and specializes in movement disorders. Today, she's going to help us try to figure out what tremors are about. Lauren, my patients talk to me about tremors pretty frequently, and there are different kinds, right? Could you clue us in and tell us a little bit about the different kinds of tremors that people might experience.

Dr. Schrock: There are several types of tremors, but there are two most common ones that people will see in friends or family. Those include Parkinson's disease tremor and . . .

Dr. Miller: That's the one you don't want to have, right? That's what people, I think, might be worried about.

Dr. Schrock: That's what people worry about most commonly when they come in, actually, but they happen to have something called essential tremor.

Dr. Miller: That's more common.

Dr. Schrock: That's more common than Parkinson's disease. There are clear differences between the two. With essential tremor it's mostly tremor, and that's your main symptom. What's unique about it is it doesn't occur when you're resting. If you're resting and not doing anything, your hands are very still, whereas when you try to do something with your hands, such as writing or even holding a coffee cup, your hands will be tremoring. That's something unique.

Dr. Miller: This is interesting, because I remember my grandfather when he reached out to pick up his peas with a fork he would have a lot of trouble with that. Then, of course, when he was resting he didn't have that tremor. He would always tell me that he thought this was Parkinson's, and I guess that's not true.

Dr. Schrock: That's a common misconception, and people really worry about it. That's what they come in frequently to my office worrying about. The reason why they worry is they think of Parkinson's disease, correctly, as more of a progressive disorder.

Dr. Miller: They worry that that might be the start of a long, progressive problem. Essential tremor, it can start mild and stay mild, or does it progress also? Does the essential tremor get worse?

Dr. Schrock: Essential tremor definitely can get worse. Really, when it comes down to it, probably two decades from now we're going to find out there are many different types of essential tremors. There are a lot of varieties of the different severity of tremor, what part of the body it includes. Most commonly . . .

Dr. Miller: So it's not just the hands?

Dr. Schrock: It's not just the hands. Head tremor can be involved, head and voice tremor.

Dr. Miller: I've heard some people that sound like their voice is almost trembling when they talk, and you wonder if they're anxious. Actually, it's the essential tremor, that type of tremor at least, right?

Dr. Schrock: It definitely can be. There's one other thing that can be mixed up or misdiagnosed as essential tremor, and that's something that's much more rare, so most people haven't heard of it. It's something called dystonic tremor, something when someone has dystonia, meaning abnormal spasm of a muscle that causes either pulling or abnormal postures.

Dr. Miller: Is essential tremor mostly in both hands, or is it usually in one?

Dr. Schrock: In most people, essential tremor will come on in both hands. Most patients who come in will complain of it more in their dominant hand, of course, but when you actually examine them they'll have the tremor in both hands. Whereas with Parkinson's disease, by definition it starts with one hand and at rest, so the Parkinson's tremor will be where someone is just sitting down. You see their hand moving on its own, tremoring rhythmically. Often, people describe it as a pill rolling tremor. You'll see the movement of the thumb and the finger kind of together.

Dr. Miller: But the essential tremor is a little finer tremor, it's worse as you move towards something or try to do something. It's a finer base tremor. I guess sometimes it can actually be a pretty marked tremor, depending on who has it.

Dr. Schrock: Yeah, it can become severe. Most people don't come into a doctor for essential tremor. There's a lot more essential tremor out there than we see in our clinics.

When people have done studies just knocking on doors and seeing if someone has tremor, the rates are much higher than would be estimated just by how many people come to clinic. Because the majority of people, really it's probably relatively mild, so they don't see a physician about it. In general, when you look at essential tremor you can have some people who have a very fine tremor, almost even a jerky sort of tremor, and then you can have other people who will have a tremor that is much more severe. For example, when they hold up their hand in front of them their finger may move up to three inches.

Dr. Miller: Wow, that would be very difficult to live with, I would think. Do essential tremors travel in families? Are they associated with a family history? Because many of my patients will say, "Yeah, I really haven't worried about it because I knew my dad had it and his mother had it."

Dr. Schrock: Yes. It's very common to see essential tremor strongly travel in families. In medical school, we're taught that it's what they call autosomal dominant disorder, so that each child has a 50 percent chance of getting the gene.

Dr. Miller: Is that still true? Does that hold?

Dr. Schrock: I would say there's definitely a sub-group where you definitely see that, but as I mentioned before, essential tremor probably includes many different tremors, some of them where you see clear family inheritance and others where you actually don't.

Dr. Miller: What about the age difference when these tremors might develop? Does the Parkinson's tremor occur a little bit later, that pill rolling tremor you described? Is that a little bit later on in life, or essential tremor earlier in life?

Dr. Schrock: On average, when you look at the large groups, you will see that essential tremor comes on a little bit earlier than Parkinson's disease. However, even within a single family who has multiple family members with this essential tremor, you may have one family member who has the onset at age 20 and another family member at age 75. There really is not a clear indicator of what your diagnosis is based on the age of onset.

In Parkinson's disease, the large majority of patients have their onset in their 60s, 70s. However, there is a small subset of patients who can have early onset Parkinson's disease. A great example of that would be Michael J. Fox who had his onset around age 30.

Dr. Miller: Also, tremors are related to certain drugs, I think. A lot of us think about people who maybe are withdrawing from alcohol having a tremor. Is that actually a tremor? Is that something that is separate from what we've been talking about?

Dr. Schrock: The answer is yes and no. You can get that with certain drugs. Most commonly, I'm thinking of drugs that block dopamine. That would be in a class of medicines called anti-psychotic medications or medications that can be used for mood stabilization. An old one is called Haldol. Those can cause a Parkinsonian tremor. That's a very true tremor. The tremor will go away when the medication is taken away, but it may take up to six to 12 months for the tremor to actually go away.

Dr. Miller: A long time. I didn't know that.

Dr. Schrock: Then, there is another. You're talking about withdrawal of alcohol, for example, or someone who is under stress. This is something I often describe to my patients who have tremors, because tremors always worsen with stress, whether it be stress of having the flu or stress of having your mother in law coming to dinner.

Every single human being has the potential to have tremor. What we call that is physiologic tremor. Whenever someone is extremely hungry, didn't get enough sleep, they will get some very fine tremor in their hand. There are sayings called to shake with rage. Well, there's a reason for that. Because humans . . .

Dr. Miller: I've had that. It seems like that's about three times a week.

Dr. Schrock: . . . have a natural inherent tendency to have some tremor during times of stress.

Dr. Miller: What would you say to the person that develops a tremor? Should they see a physician about the type of tremor they have if they're concerned? Could they by looking on the web to figure out if it was an essential tremor and maybe diagnose themselves?

Dr. Schrock: In self-diagnosis, I've definitely had patients who've correctly done that, but I would beware. I think that anyone who has a tremor and has a concern about it should bring it up to his or her primary physician. If you're worrying and it's bothering you, then you definitely should see a physician about it.

Dr. Miller: Finally, there's treatment for both types, correct?

Dr. Schrock: Yes. There are treatments for both types. They are very different, the approaches to treatment.

Dr. Miller: That would require a physician to make the diagnosis and provide the treatment. Thanks very much, Dr. Schrock.