Dystonia: The gold standard

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GAINESVILLE, Fla. (Ivanhoe Newswire) — Dystonia is a mysterious neurological disorder that causes muscles to “freeze up” or work inconsistently. It’s the third most common movement and muscular disorder, affecting more than 250,000 children and adults nationwide and there is no cure. A delicate procedure called deep brain stimulation has been available for about a decade and experts say this has now become the “gold standard” for relieving symptoms of dystonia in some patients.

14 year old Felipe Hanel loves comic books, but his story is one that really stands out. He was diagnosed with dystonia, a neurological disorder where the muscles fight each other, affecting posture and movement.

“It started showing up as I was eating. When I would drink, my hand would shake when I would take my spoon and my fork. I was walking with a noticeable limp.” Hanel told Ivanhoe.

Medications didn’t work, so Hanel’s family decided to try deep brain stimulation, or DBS. Doctors put a pacemaker in his chest and then connected it to the wires that lead to his brain. He was “awake” so he could respond to the stimuli.

“We try to understand where the signals are going wrong in the brain and we try to unscramble the signals by applying electricity to different areas.” Dr. Michael Okun, a Neurosurgeon at the UF Center for Movement Disorders & Neurorestoration in Gainesville, Florida told Ivanhoe.

Dr. Okun claims it could take weeks or months to start feeling the effects and sometimes adjustments are needed. “Just tiny amounts from these leads affect these circuits and have such profound improvements for patients.” He said.

For Felipe Hanel, he has a cutting-edge treatment and a Dr. as his new superhero.

The batteries in the pacemaker do sometimes require patients to undergo a surgical replacement procedure. In addition to the treatment of dystonia, deep brain stimulation is also used to help treat Parkinson’s and Alzheimer’s.

BACKGROUND: Dystonia is a neurological disorder that causes muscles to contract and create uncomfortable, abnormal postures. There are different types of dystonia that affect different muscles in the body and can occur at any age. The types include cervical dystonia, blepharospasm, cranio-facial dystonia and task-specific dystonia. For someone dealing with this disorder, they may experience sporadic involuntary movements and turns from the neck or the foot. These muscle contractions may also happen after a period of physical activity. Other symptoms include rapid blinking from the eyes, body tremors and difficulty speaking. (Source: http://www.ninds.nih.gov/disorders/dystonias/detail_dystonias.htm)

CAUSES: Doctors do not fully understand what causes dystonia. Researchers believe that the disorder may result from damage or dysfunction to parts of the brain that control the body’s movement. Cases of dystonia are classified into three groups (idiopathic, genetic, acquired) based on what doctors believe may be the cause. Many cases of dystonia are labeled as idiopathic which means there is no clear cause. Genetic dystonia is usually caused by a defective gene passed down by one parent. Acquired dystonia is caused by environmental surroundings like a physical accident to the brain. (Source: http://www.medicinenet.com/dystonia/page2.htm#what_do_researchers_know_about_dystonia)

NEW TECHNOLOGY: By using deep brain stimulation (DBS) doctors at the UF Health Center for Movement Disorders & Neurorestoration may now have a new way to fight dystonia. DBS uses an implanted device to send electrical signals to the brain in order to disrupt and scramble the dysfunctional signals from dystonia. Doctors first implant neurostimulators under the patient’s collarbone and connect these stimulators to the brain. Everything is under the skin with no external parts or wires. DBS has been used effectively for people with Parkinson’s disease and Alzheimer’s; treating over 30,000 people across the globe. The program at UF has reached a milestone of 1000 DBS leads. The positive experience with both Parkinson’s and Alzheimer’s treatment is leading DBS to become the gold standard for treating dystonia. (Source: http://www.spasmodictorticollis.org/index.cfm?pid=114&pageTitle=Deep-Brain-Stimulation-for-Dystonia:-What-You-Need-to-Know)

Michael S. Okun, M.D., Co-Director of the UF Health Center for Movement Disorders and Neurorestoration, also Professor of Neurology at the University of Florida and author of Parkinson’s Treatment: 10 Secrets to a Happier Life.

Can you explain what dystonia is?

Dr. Okun: Dystonia is a neurological disorder where the muscles fight against each other. The problem is in the brain and it’s in the signals that are being sent down to the muscles resulting in twisted postures of arms or legs, or sometimes even the voice. One might assume that it’s a muscular problem but it’s actually a problem where the brain signals are scrambled and the muscles aren’t firing in sequence.

For example, when you try to make a movement, most of the time one of your muscles has to contract and the other one has to relax in order for you to make this movement normally and fluidly. The most common situation is when you want to flex your arms so you’ll need to contract your bicep and relax your triceps. If these two muscles are contracting at the same time, however, you can end up in abnormal postures, and you can end up with something called dystonia. Dystonia can affect any part of the body. When it does affect body parts and becomes generalized, it can become very disabling for people suffering with this disorder.

And treatment for this?

Dr. Okun: The treatments for dystonia include medications, surgeries and also other behavioral and rehabilitation approaches. There are a lot of different forms of dystonia and it turns out that the medications don’t work really well. So we have medicines that can block receptors in the brain called anti-cholinergic receptors. When we block them with certain medications, we can improve the dystonia. A lot of times in adults and in kids, this can affect school performance or cognitive or thinking performance and there’s a price to pay for some of these drugs. There are muscle relaxants and there are other drugs like benzodiazepines that can relax you but also sedate the muscles, as well as pharmacological and medical approaches to dystonia have been less than satisfying.

There are rehabilitation techniques too but again it’s very hard to get muscles to stop contracting. Then there are certain muscles like the voice box that are very hard to get to. Our best strategy to date has been using a therapy called deep brain stimulation (DBS) where we try to understand where the signals are going wrong in the brain and we try to unscramble the signals by applying electricity to different areas. We use a system that essentially pushes electricity from the pacemaker that’s located in the chest, through a wire and to specific regions of the brain to try to give a more normalized brain signal pattern and improve the quality of life for people with various diseases including dystonia.

So that’s what Felipe has? Like a pacemaker right?

Dr. Okun: Since Felipe received the pacemaker, and unlike a cardiac pacemaker the wire doesn’t go to the heart but goes up to the brain, it reminds me of one of the early leads that we’ve done. We’ve actually implanted over one thousand of these DBS leads. I remember one procedure where a patient needed to get a chest x-ray because they had pneumonia; the radiologist sent back a report that said the pacemaker was in place but had a wire going the wrong way! When you see a pacemaker, you’re used to seeing the wire go to the heart, but in this case these types of DBS pacemakers are actually pushing electricity into very small regions of the brain in order to improve the symptoms. Nobody could have predicted that you could put this much (less than a finger-nail- sized amount) of electricity into the brain. Just tiny amounts from these leads affect these circuits and have such profound improvements for patients who are suffering with diseases like dystonia.

So this really is what works.

Dr. Okun: At the moment, this is our best symptomatic therapy for dystonia. We’re still searching for things that may modify the progression of disease and or cures. We found very few cures. In the case of dystonia, these kids and young adults who suffer from it have otherwise very normal brain function. In fact many of them have much higher than normal IQs and they become doctors, lawyers, accountants, and CEOs. These are really high-performing kids and adults who are held back by this dysfunction.

Applying a powerful systematic therapy-like stimulation surgery is a great way to improve their quality of life. But make no mistake about it, we want to understand these therapies, including the mechanisms of how electricity works on this complex circuitry, to develop better and more focal ways to get at these disorders and help more people.

Are there any side effects to this?

Dr. Okun: When we push electricity into the brain, certainly there can be side effects that happen because of the company that the lead keeps in the brain. If you look at all the structures, the brain is like a group of islands and it’s very different than the gallbladder or the liver because all of these islands are talking to each other, and they’re sending out neural signals. Very small changes in distance between two structures are actually huge on the scale of how we measure things (in the brain). If you look at the millimeter ticks on a ruler, two, three, four ticks they can be like the difference between the distance between Florida and California or Florida and Australia—especially in the context of getting into the correct circuitry. Mapping the leads, and being able to understand physiology and get these into the right brain regions, is part of the way that these procedures can be successful so you can limit the spread of electricity into the circuit and into the regions that are going to help you to unscramble those signals. However, it’s almost impossible with the current technology to put a straw down that has little electrical contacts and turns them on and expect to get into these very sophisticated and small circuitries.

When electricity spills into circuits that we don’t want, people may have problems with slurring of their speech or double-vision or problems walking. The silver lining of stimulation therapy and pacemaker therapy is that we can adjust it. There are thousands of different combinations and so, although not all side effects are reversible, if the side effect occurs because of the way we deliver stimulation to the brain, we can change that. We can shape the candy-like impulses into different-shaped candies to get into certain areas and stay away from other areas. We can deliver different size pulses. We can make them faster or slower. In fact, we have a lot of research in our laboratories looking at novel ways that we can deliver these pulse forms to be more efficient, use fewer batteries, and affect the symptoms in the circuits that we want to get into.

How long does it take to kick in after the surgery? Are the improvements in weeks or days?

Dr. Okun: The time course after stimulation surgery is one of the most fascinating things about deep brain stimulation. It’s different across different disorders. If you have a tremor and you’re shaking when we turn on the DBS device, we see almost immediate improvement in that tremor. Now it takes us a while to get the exact right settings for you as an individual person, so this is a very personalized therapy, and in my mind is the greatest example of personalized medicine that we could ever give. People have specific ways that we have to stimulate their brain and specific regions. But we see very different effects across the diseases that we tried to approach with the therapies, so a tremor responds right away. Parkinson takes a little bit longer.

Dystonia is a curiosity because when we started to do these cases over a decade ago, we would turn the leads on and nothing would happen. This was highly disappointing, so you’re doing research in the lab and you’re trying to understand the circuitry. You have a child or young adult, you drill into the brain and you put a straw down and you push electricity into that area and nothing happens. Like a lot of things in life, there’s delayed gratification. Down the road, we began getting phone calls, “Hey, I think there’s something going on with Felipe’s hand or his neck.” Then a few weeks later, we’re starting to see some changes in handwriting, and the arms and the legs are looser. A few months later, he’s starting to have some better mobility. Then one day six months later, he wakes up and tells his mom, you know, mom, I think I can walk, throws aside his wheelchair and gets on the bus with the kids and goes to school. How does that happen? If we give it in a disorder, like tremor, and we see immediate response, then we give it in a disorder like dystonia and over time, we see these changes. What’s going on?

We believe that there is a neural plastic response in the brain so the brain is actually remodeling slowly over time in response to the electrical current. The circuit, in some way, is righting itself or at least moving to a less pathological state that then can lead to improvement in symptoms. It’s a really interesting phenomenon that we don’t completely understand. But when we get a hold of, what we call the pathophysiology or the underlying reasons why this happens, we’re going to be able to develop better drugs, better therapies and better genes. We need to understand this process because you can imagine if we give a drug for dystonia, most drug studies may follow a patient for six weeks or eight weeks. It may be that it takes a brain longer in a disease like dystonia to be able to attack this. We’re very interested in using this therapy as a model to understand the disease and the profound benefits that we’re seeing. It should be teaching us about where we need to go next.

We should, of course, celebrate the benefits that we’re seeing across these patients but understand that there’s something to be learned and we haven’t completely figured it out. We also have people with dystonia that get the stimulation surgery and don’t respond. We need to understand why certain people are responding and why certain people are not. We know that certain targets may be better for specific symptoms. So it’s understanding targets versus person, versus symptoms, versus what do you want to get better in your life. We have some ground that, I think, is important for us to travel but there’s still a long way to go for us to understand this mysterious disease and try to get a hold of the manifestations to help as many people as we can and use the knowledge to advance the therapy.

So you’ve done this a thousand times.

Dr. Okun: We’ve done one thousand leads and when we put a lead into the brain, we take the patients to the operating room. One of the things that I do for a living is listen to brain cells sing, and I try to make maps and figure out where the right spots are for these electrodes to go. Location is one of the most important determinants in an outcome. We’ve done this for lots of different diseases including dystonia but also tremor and Parkinson’s disease and certain forms of ataxia and some memory loss for Alzheimer’s, obsessive-compulsive disorder, Tourette syndrome and there are now studies in epilepsy.

So there has been an expanding number of potential indications for any disorder that operates as a circuit in the brain where that circuit is still intact enough that we can tinker with it and reconfigure the signals to neural modulate in a more healthy way for that individual. That’s sort of what we’ve been up to in our laboratory and Dr. Kelly Foote, a UF Health neurosurgeon, is actually implanted over one thousand leads. I’m just the navigator; the guy that sits in the seat behind the pilot in this two-man operation. He’s the one that’s actually had the courage to approach these children and young adults and perform these operations. It takes a team and I think we have one of the better teams on the globe at doing this! It’s not always a walk in the park and you don’t always see what you expect to see. You’ve got to be very precise and the team has to really understand how to navigate, how to coach the families and how to work through getting resolution which can be a longer horizon on patients with dystonia. We see patients from all over the world here and some of our dystonia kids pick up and start responding within a few months but some of them can take six to eight months or even a year.

We just saw a child couple of weeks ago and it took him over six months to really start to see the benefits. We have to pace our families and help them understand that we don’t completely know exactly the way to apply these therapies and we have to have a longer-term horizon. We have to be very careful and cautious but also understand that when it doesn’t work, there might be a reason and we might learn from that. We’ve learned from our failures as well as from our successes and probably the most important thing that we’ve done over the years was to develop a troubleshooting clinic for deep brain stimulation. It’s the largest one in the world, we see one or more patients every week from all over and they come with problems with their DBS devices. There are more than 100,000 people now that are bionic and they come here wanting some answers. Working through those problems, sometimes replacing leads, sometimes doing programming, sometimes adjusting medications, adding behavioral therapies, physical occupational speech, swallow, understanding what we can do for individual patients to try to improve their outcomes. It’s been more instructive than just high-fiving and congratulating ourselves when we have a big success on an individual patient.

As we move forward with these types of therapies, we need to be troubleshooting, asking why and we need to always be looking at the negative as well as the positive. When we see side effects, what can we build to get away from the side effects? What technology can we use to advance the field further? And which sorts of devices are we going to need to be using in five or ten years that are different than what we’re using now? There are a lot of great and interesting questions that are in front of us but the privilege and honor is to work with the patients who are suffering with the diseases and have had enough courage to let a couple of guys try things to see what we can do. We try to make their lives better but also they’ve had the courage to allow us to use their neural recordings and to take lots of scales and begin to try to better understand from a numbers point of view what’s going on. We want to use that information to try to innovate into some areas.

And this is probably the best thing yet?

Dr. Okun: In the dystonia world, stimulation surgery is by far the most effective and efficacious approach that we have in our armamentarium. However, for people who have focal dystonia with the most common form being torticollis with a tilted neck with neck pain. The best treatment for that disorder is botulinum toxin. Once you start getting dystonia in multiple parts of your body, you can’t keep shooting Botox every three months and there’s a certain amount that you can give and it is not very effective for more generalized or even what we call segmental dystonia, when two body parts are involved, and so there are these cases where you need more. Right now, for the most severe cases of dystonia, this is the best approach.

Now I should mention that in children and in young adults we look very carefully at people who are considering stimulation surgery and we look earlier than we did before. We are looking earlier because we know that when you have an abnormal posture or when your leg is turning in when you’re walking and taking every step or when your arm is doing something funny, if you keep doing that over and over again, the bones can change and you can get contractures. Once you get a bony malformation and a contracture that becomes fixed in any joint, then the chances of us being able to unscramble the signal and unscramble that joint go way down to almost zero. We look at people like Felipe and we look at others who have these problems and our radar goes off and the threshold goes down. You don’t want to see them progress to that point because you’ve waited so long that they end up with a contracture that is going to affect them for the rest of their lives.

The field is evolving and we're now seeing consistent successes. We’re also now beginning to try to plan the future of these young people that are getting these operations. We’ve also noticed in an accidental byproduct of the surgery was as we brought people off of the cholinergic drugs, we knew the effects they had on their memory. We also knew that children could tolerate much more than adults but their school performance went way up by getting them off of these medications. If it’s possible to reduce doses or get patients off these medicines, they get added benefits to a part of their lives that they’re not going to get back. There are early adolescent years where your brain is developing and you’re developing the right social skills and all of these things that are going to be important to integrating into society. So it’s really important for us to pay attention to these types of issues.

Do they have to replace the pacemaker after a while? What would that be like?

Dr. Okun: The pacemaker or impulse generator that drives the DBS lead is on a battery. The batteries are pretty good, and in diseases like tremor and Parkinson’s, they’ll last for three, four, or five years. In dystonia, many of those batteries, depending on and how much energy we have to use, could be gone within six months or a year or year-and-a-half. What we’ve noticed over time with using novel stimulation patterns in ways that we deliver the stimulation, is that we’re able to use shorter frequencies and make those batteries last a few years longer.

We also have rechargeable batteries that are available and FDA approved for other uses that can sometime be applied to dystonia. The biggest challenge is, if it’s not FDA approved, it may not get paid for and that’s going to require battery changes for those patients depending on how much power would be put into their device. Ultimately, we would like see all these kids with rechargeable devices so that they don’t have to have repeat surgery. Repeat surgeries mean increased risk for infection.

You have a mobile app, can we talk about that?

Dr. Okun: Yes, we have a mobile app we’ve developed. Actually a number of students in our laboratory, Mike Montuno, Kaihan Fakhar, and several of these really talented young people, recognizing a problem which they solved during their summer research rotations. Patients were coming in and batteries were running out and as batteries ran out, the symptoms got worse. This is especially troublesome in diseases like dystonia because you’re asking more from the battery because you’re using it more than in Parkinson’s. The battery wasn’t designed to be pushed that hard. What happens is that the patients start to get a return of symptoms earlier, even when the battery is still good, because it’s not designed to be pumping out that much power. If you let the battery run out, people can get rebound symptoms with severe dystonic storms that can be very terrible, sometimes landing people in the intensive care unit with dystonia.

Understanding how to monitor battery life is important. These medical students developed the really neat application that people can use on iPhones; a joint app to monitor the battery life of their device. They can plan preemptive changes. If there’s a change in their symptoms, even if the battery looks pretty good but has been in for a while, there’s a plan that can be implemented to change that battery because the problem might be that the battery just can’t keep up with the demands that have been placed on it.

Dr. Kelly Foote and I’ve done all the procedures here but he has been a driving force behind this deep brain stimulation program. I’ve been his navigator but he’s been amazing, not only taking care of the electrical problems in these people’s brains, but also taking care of the families and taking care of the patients. He’s now done this over one thousand times and I assume he’s going to do these thousands of times more with better refinement and technique and improvements in technology.

The care of the neurosurgeons for these families really makes a big difference. It's not like a simple gallbladder or hernia operation. You know these patients have to be screened by seven or eight different specialists over a two-day period. There has to be an interdisciplinary discussion among all the specialists. They get together and talk and this is led by Dr. Foote from Neurosurgery. I always tell people the highest level of care you can hope for in the American healthcare system is that people talk behind your back. That’s when you know everybody is on board and they’re looking out for you and trying to get you the best possible solution. They can choose targets in the brain, they can choose approaches, they can say one-side, two-sides, how is this going be managed and who’s going to be part of the management team before, during and after the operation? It’s like planning a really good sports season. It takes a lot of coaching and it takes a lot of effort by many team members that have to work together like musicians in a symphony. I think that Dr. Foote has done a tremendous job putting in over one thousand of these leads and conducting this symphony.

What’s the procedure like for changing the battery?

Dr. Okun: The battery change procedure is relatively simple. It takes about 30 minutes, but it does require the incision to be opened up over the area where the battery needs to be replaced and the battery pops out and we put a new battery in and connect it to a connector-wire and sew up the incision. If we do this multiple times over multiple years the more times we do that, the more risk that we introduce for infection. This is why we encourage patients, particularly with dystonia, to start wrestling with their insurance companies now to get approved to get a rechargeable device that insurance companies currently won’t cover because of the FDA approval. If they can get an exception and get an approval, they can reduce that infection-risk potentially and keep those batteries in during longer periods of time. It’s also in the best interest (as Dr. Foote points out) for the insurance companies to do this because it actually will save them money over the long term. It means fewer surgical procedures, less morbidity and better outcomes, particularly in a disease where that battery is asked to do a lot and has to be replaced more frequently.

This information is intended for additional research purposes only. It is not to be used as a prescription or advice from Ivanhoe Broadcast News, Inc. or any medical professional interviewed. Ivanhoe Broadcast News, Inc. assumes no responsibility for the depth or accuracy of physician statements. Procedures or medicines apply to different people and medical factors; always consult your physician on medical matters.