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Current time:0:00Total duration:9:01

Managing Parkinson's disease with surgery

Video transcript

so we know that when the movement symptoms of Parkinson's disease start to interfere with a person's day-to-day living that's when we would normally try to find some medications that can help manage help minimize the problems right but we also know that the most effective medication that we currently have l-dopa can cause some side effects after several years of use that also need to be managed like dyskinesia and and wearing off and because Parkinson's disease is a progressive disease because it continues to worsen over the years following diagnosis sometimes medications just can't keep up with how bad the symptoms get and as a result they just can't manage the symptoms anymore so if our person with Parkinson's disease gets to the point where their quality of life is just too impacted by the disease itself or by the side effects of medications that they have to be on well that's when surgery to help manage the symptoms might be considered and the particular operation that's often useful in Parkinson's disease is called deep brain stimulation or DBS and DBS is actually really interesting it's it's kind of like a pacemaker you know those electronic implants that help you regulate your heartbeat but instead of being for your heart DBS is like a pacemaker for your brain so what it does is it's actually kind of it's kind of interesting because we don't really know how it works this is just what's been observed over the past 20 odd years or so but what it does is it helps to reduce the movement symptoms of Parkinson's disease the brady kinesia and the tremor and the rigidity and it can also help with the dyskinesia that can result from long-term use of l-dopa so let's actually take a quick look at how this procedure is carried out here so a DBS operation is actually done in kind of two main steps so the first step is kind of like a surveying step so what happens is that a little wire called an electrode is very skilfully and carefully inserted into the brain into the area of the basal ganglia so we can think of this initial set of electrodes as like our undercover agents right they're gonna keep their ears to the ground so to speak and and find out where all those misbehaving neurons are where they're hanging around in the brain because it's one thing to say look at a textbook or a nice drawing and and see exactly where our nuclei are but it's an entirely different thing to be able to accurately find these areas in live human beings in surgery so good thing we have our undercover agent electro is here to help us out right and I said that they keep their ears to the ground and I almost literally mean that they actually work by analyzing the activity patterns of neurons that are around them and then what they do is they translate what they find into distinct sounds sounds that we can hear so the surgeons that are doing the procedure can hear these sounds and say AHA this is the spot when they've actually reached the right place in the brain and this can take quite a while to do it can take several hours per hemisphere of the brain depending on the person okay so step two now are our Undercovers have done a really great job at kind of mapping out the important areas that we need figuring out where we need to go so we pull them out and in goes some permanent electrodes to those areas so let's draw that here on our guy and we can also see what that looks like on an MRI so here's an MRI kind of the same sort of view that we're looking at and you can see those electrodes here on both sides of the brain so the idea is that these electrodes they stay in the person's brain permanently now on maybe just one side of the brain or maybe on both sides of the brain depending on the person's symptoms and the severity of those symptoms and in case you're wondering about a power supply they're actually connected to a battery-powered pacemaker down here that's normally put below the collarbone so now we have the ability to continually send electrical signals to the part of the brain where those electrodes are right the part that's causing the movement problems and the electrical signals that are sent what do they do well they adjust the activity of the neurons here so this is kind of like adjusting the knobs on a radio right we tune into the station that we want in this case movement and we do this by placing those first electrodes our undercover agents in some of the movement areas like parts of the basal ganglia and now what we're doing is we're adjusting the volume we're turning it down to turn down the activity of the troublemaking neurons in these areas of the brain and that's actually part of the beauty of DBS this is actually a reversible setup that allows us to fine tune how much these neurons are turn down and what's extra great about that is that it means this setup can be adjusted to individualize it for different patients now let me just make two clarifications here so just from when you look at the named deep brain stimulation you're thinking okay deep brain well where is that so in the case of someone with Parkinson's disease our target is the basal ganglia area which is pretty deep in the brain right so that's that and the second thing is that the second half of this name is stimulation but I just told you that we're turning down the activity of these neurons so I think an analogy that I'll give you is think about when your dog is barking uncontrollably well you tell him to quiet down right you're talking to him still counts as stimulation even though then the end result is that you're turning his volume down so that's kind of the idea with our electrodes and our basal ganglia here even though we're stimulating the brain the end result is that the the activity of the neurons is turned down and let's actually look at where in the basal ganglia we're talking about here with Parkinson's disease so in order to kind of figure out where we would want to go let's think back to how the basal ganglia control our movements so remember that in Parkinson's disease our thalamus it's is not able to talk to our motor cortex as much as it needs to and so we end up with a reduction in movement right and remember that this happens because the subthalamic nucleus it gets too active right and when it's too active it over excites the Globus pallidus internal and when the Globus pallidus internal is too excited it's what inhibits our thalamus too much so that it can't talk to the motor cortex properly so right away we can probably see that the Globus pallidus internal is definitely one of those problem causing areas in Parkinson's disease because it's too active right it's inhibiting the thalamus too much and another area that we can probably see is a problem causing area is the subthalamic nucleus right because it's the one that's getting too active and over exciting the Globus pallidus internal in the first place so it turns out that these are indeed the main areas that we target with DBS for someone who has Parkinson's disease so we use DBS to turn down the activity of the neurons in these areas these areas that are too active and that allows us to restore the balance in our direct and indirect pathways and I mentioned this already but how DBS works is still a bit of a mystery we haven't quite figured out how targeting these areas with DBS manages to reduce the movement problems that we get from Parkinson's disease and in long term use of l-dopa we just know that it consistently works and one kind of added bonus of DBS is that it often allows the person with Parkinson's disease to reduce or discontinue some of their medications so that's a really good thing right because we know that some of those medications can bring on some bad side effects so for example remember how l-dopa is kind of like a pendulum that wants to bring our patient from too little movement to normal but after a few years it can kind of overshoot right and cause too much movement well we want to avoid that if we can so with DBS helping to manage the movement problems in the first place the patient can often get away with taking less l-dopa which can maybe help our pendulum here from swinging a little too far and causing too much movement so good that's surgical intervention so now we know that we have medications and if needed later on surgery that can help manage some of the symptoms of Parkinson's disease but we have another category that we'll quickly touch on and that's lifestyle management options so for example exercise and physiotherapy while they won't stop or slow down the movement signs they can help to alleviate some of the associated muscle and joint pain that can result from things like rigidity and the postural changes that can happen over time with Parkinson's disease and another thing that can be really helpful is speech therapy and and that's because a lot of people with Parkinson's disease they tend to develop really soft speaking voice due to a lack of coordination of muscles in the voice box so speech therapy can help kind of train them to increase their speaking volume and that allows them to continue to converse with the people around them and one last example is emotional and psychological support this can be really important for someone with Parkinson's disease so this can be really helpful early on when the person is kind of just learning about the disease and starting to cope with it and it can also be really helpful later on because remember that the disease can start to affect the person's mood right it can cause problems with depression and anxiety so this support can be really helpful if this happens for someone with Parkinson's disease