Podcast: Using deep brain stimulation to treat Parkinson’s disease
Deep brain stimulation (DBS) is an increasingly common procedure for neurological disorders, including Parkinson’s disease. This week's episode of A Grey Matter features Professor Peter Silburn, Director of the Queensland Brain Institute’s Asia-Pacific Centre for Neuromodulation. Professor Silburn is a neurologist and world expert in DBS. He and neurosurgeon Associate Professor Terry Coyne have together performed more than 800 DBS procedures. Professor Silburn discusses Parkinson's disease, DBS, and the wonder of the human brain.
Transcript
[MUSIC]
Kirsten MacGregor
Hi, I’m Kirsten MacGregor, and you’re listening to A Grey Matter, the neuroscience podcast from the Queensland Brain Institute. It sounds like something from a sci-fi movie, but Deep Brain Stimulation, or DBS, is an increasingly common procedure for neurological disorders, like Parkinson’s disease. It still requires highly specialised skills of course, like those of Professor Peter Silburn, from the Queensland Brain Institute’s Asia-Pacific Centre for Neuromodulation. Peter divides his time between research a clinical work, and along with his colleague, Associate Professor Terry Coyne, has performed more than 800 DBS procedures over the past 20 years. Together, they have trained most of the DBS practitioners in Australia. The potential for DBS is vast, as I discovered when I caught up with Peter to mark World Parkinson’s Day.
Professor Peter Silburn
Deep Brain Stimulation is a technique where you place electrodes in the middle of the brain, and you find areas that aren’t working properly, and you’re able to stimulate them to improve the function. And these areas in the deep brain spread out to the rest of the brain, but also of course control other things in the body.
Kirsten MacGregor
Can you talk me through the process by which you put the electrodes in?
Professor Peter Silburn
Putting the electrodes in the brain really involves a whole time, which is good and it’s important to do that. And once we have an idea of where the target is, we like to confirm we’re in the target, and we like to test-stimulate there before we leave the electrode in permanently.
So really, the process that’s necessary to find the target, that’s kind of not sufficient, you have to have the right person, with the right condition, and have a whole lot of team, because the brain requires programming after we put the electrode in, so we have to be able to talk to the person’s brain without touching it, and how we do that is if we come back, you have to find the target, so we have to get very good images of the brain, and we have that now at the University of Queensland with a very powerful scanners. Once we can see the target, we then place the electrode down, carefully of course, and we look for cells that are working fine, so we can watch actually individual brain cells and the person is awake. And we can ask them questions, and we can see tremors stop, or hands become easier to use again, all sorts of different things, the brain controls a lot. The final thing then is that we’ve seen the images, we know the targets there, we have confirmed we’re in there, we’ve test-stimulated it, and then a permanent electrode is places there on a lead that comes up through the brain, on top of the bony part of the skull, and under the skin there, so you can’t see it, and then it tracks down to what we call a pacemaker, like a heart pacemaker, it’s like the brain stimulator, and then we can talk directly to those neurones and tell them how we want them to work.
Kirsten MacGregor
I’m still way back on, “you can talk to the patient” during the process. So you’re drilling through their skull, you’re embedding an electrode in their brain, and you’re talking to them?
Professor Peter Silburn
Yeah, it’s interesting – the yucky bits, if you like that, people are asleep. But once we’ve finished drilling the hole, and my colleague Associate Professor Coyne, this is about 859 cases we’ve done, he knows what he’s doing to be able to do that comfortably and clearly, so we can get the probe down there. So the yucky bits are done while people are asleep, and then once we’re happy, we wake them up and talk to them. They cannot feel these things because the brain itself has no pain – it’s where pain is interpreted, but not really feeling it.
Kirsten MacGregor
Does that mean you’re seeing instant results – someone can tell you straight away that symptoms of, say, Parkinson’s, have been allieviated?
Professor Peter Silburn
Yeah, we can see things immediately in Parkinson’s, which is a condition that affects motor things – tremor, stiffness and slowness – but other non-motor things, like thinking, and mood, change in sense of smell, sleep, all these non-motor things in Parkinson’s can be equally disabling, but we can see motor things pretty straight up quickly.
Kirsten MacGregor
Why is it so effective in Parkinson’s?
Professor Peter Silburn
Parkinson’s, it’s been around a long time, the surgery. Many years in fact. And why it is so effective is that these circuits in the brain have been well-worked out over time, we know the nodes of movement in the brain, and we know where to go, so once we’re there, we really know how to stimulate them, and it has an immediate effect. The brain cells themselves work in milliseconds, so if you’ve got a group of brain cells that are effecting tremor, say, movement, and we can find them and stimulate thme, the effect is within milliseconds.
Other conditions that we operate on may take some other time.
Kirsten MacGregor
What have been some of the most dramatic results you’ve seen then in Parkinson’s patients?
Professor Peter Silburn
The biggest thing we see in Parkinson’s patients is relief, and that’s probably the biggest thing. And then the next thing is people suddenly have choices, so you see completely disabling tremor and stiffness and you can’t use your hand, you can see it pop right in front of your eyes, and some patient’s in the operation will look at their hands and watch it move, or they like the feeling of the tremor which they’ve never had a holiday from despite multiple drugs, they see it stop, and it’s quite a poignant moment in the whole of the theatre, actually, and we like to see that. We know that we’re going to give them the best chance to have choices in their lives, not knowing whether they can go out, or go visit people, because they become stiff and slow and the drug wears off. These choices enable the person, all those people around them, to actually get their lives back to how they’d like to, within limitation, because it is not a cure, but it’s a long-term lasting effect if we get it in the right place.
Kirsten MacGregor
What a gift that is for you. Most surgeons wouldn’t see instant response; instant results.
Professor Peter Silburn
Yeah, I think Terry and I have been, like I say, doing it a long time, and to this day, it’s still an amazing thing, I think, but you’re really kind of on a mission, in there, you’ve really got to get to it and give them the best shot, and then it’s later on when you think, ‘oh yeah, we did good today’. But a lot of concentration goes on. But it is, still to this day, and I’ve been involved for 20 years, a good thing to be able to do and help people.
Kirsten MacGregor
Do you ever get blasé, considering you’ve done this 859 times, about being inside someone’s brain?
Professor Peter Silburn
No, never, absolutely never, because you’re on a mission to find this area that’s like a little 1 millimitere area and you can’t see it, that’s why you’re reliant on the computers, and watching the neurones, watching the brain cells work, so you’re kind fo focused on that, and that’s your job, and what we do when the probe goes through, it doesn’t destroy tissue, at the cellular, microscopic level, it actually pushes cells apart, and as it’s pushing cells apart, we’re watching different areas in the brain and then we see where we are, and that’s a very good feeling, and then everyone can kind of relax a bit.
Kirsten Macgregor
I actually love asking neuroscientists about the brain, becaue your faces light up, this mysterious beautiful thing that’s the core of who we are, and you’re in there, Peter.
Professor Peter Silburn
Yeah, we are definitely in there, I mean people who have got the brain bug can’t shake it. When you think about it, everything in our world that we interpret is interpreted through the brain, and your actions come out of the brain. So, this conversation now, we’re thinking very fast, in a building that’s been built by the human brain, we have the capacity in the small capacity of the brain, a brain you can put in your hand, is where human thought is, and emotion, and the future, and how we can stop destroying our environment, how we go to space, but we’re quite happy to spend billions and billions of dollars going to space, which is an unkind environment for humans, we spend billions going ot the bottom of the ocean, which is again an unkind but very important environment for humans, but we don’t spend those billions and billions on a single project to work out how on earth does the brain think, but we have the capacity in functional neurosurgery and Terry and I and the whole team at QBI, we have that capacity to actually see what a thought looks like.
Kirsten MacGregor
Given all that, and that you’re aware of the enormity of what you’re doing I guess, who then is the first person then to say hey, let’s drill a hole in someone’s head and put an electrode in? How did this all start?
Professor Peter Silburn
Well the ancient Egyptians, around 3000 B.C., drilled holes in people’s skulls. It mightn’t have had such the outcome, they certainly didn’t have electrodes, but Egyptians were known to use electricity to help brain things like migranes, and slap people heads with electric eels.
Kirsten MacGregor
[laughs] Did it work?
Professor Peter Silburn.
[laughs] No! But all of this has evolved because everybody is actually involved in this – surgeons, neurologists, neurophysiologists, neuroscientists, everybody has relaised that great, help people,number one thing. But don’t waste the opportunity whilst you’re in someone’s brain to look at it, how it’s working and individual brains, and that’s the fascinating thing, and people have been adding to that information for many, many years. We’re in here now with the ability not just to help, but we’re able to watch those neurones being in the deepest part of the human brain anyone’s been, at QBI we’re been able to look at those deep, deep cells talking to each other, and look at the circuits of how the brain thinks for something like walking. So, we’re at a crude level now that we want to look at how people think and what does a normal thought perhaps looks like, and what perhaps is an abnormal thought in certain conditions, but help people and don’t waste that opportunity.
The future of humans is in the brain. If we help the environment, we’ll hang out. But if we keep destroying the environment, we won’t go forwards, so you’ve got to get these thought processes – look after our own environment, look after our own interactions with people, and develop things, just keep developing and developing. The brain, when you think about your communications in the world, what we’ve learnt from Parkinson’s work, is that the brain is very quick in its communications, so I think if we glean that we’ll improve communication between the world and try and dull down the noise that’s interfering with good signals, which is human kind.
Kirsten MacGregor
That’s Professor Peter Silburn from the Asia-Pacific Centre for Neuromodulation at the Queensland Brain Institute. You can follow QBI on Twitter or Facebook, or give us a review on iTunes. I’m Kirsten MacGregor. Thanks for listening.
Presented by Kirsten MacGregor. Produced and edited by Donna Lu.
A Grey Matter is the Queensland Brain Institute's podcast about neuroscience. It features music from Incompetech, available under a Creative Commons Attribution-Noncommercial license.
Music used:
‘There It Is’ by Kevin McLeod – bit.ly/1nW96tY