Huntington's Disease and Deep Brain Stimulation as Treatment Option
The patient's lack of anxiety, depression, or psychosis before surgery was taken into consideration prior to DBS treatment.
Full video transcript:
My name is Jessica Carl, I'm a physician assistant and I work at Rush University Medical Center in Chicago, particularly in the movement disorders section of neurological sciences. A little bit of the background first: So what is Huntington's disease in general terms? It's a progressive neurodegenerative disorder characterized by progressive dystonia, chorea, parkinsonism, as well as several different cognitive issues and psychiatric issues. In the literature, there really isn't that much known about deep brain stimulation and Huntington's disease. There's a little bit about chorea and the chorea phenotype of Huntington's disease and DBS as a treatment option for that but really not the dystonic phenotype, which is what our aim of the project was or the case report rather.
The patient was 66 years old when he presented to us and he had a 30 year history of Huntington's disease. In the last 10 years before he came to our clinic, he started to develop this disabling trunkal dystonia, so really like back arching and really throw him out of his seat. He was unable to sit in a chair, he couldn't have dinner with his family, and he couldn't go to the movie theater; he couldn't really partake in any activities of daily living. This movement was present sitting, that was the most severe, but also standing, so it really got in the way of his balance and walking and led to many different falls and also even while he was lying down, so he couldn't get to bed at night.
So he presented to us because he had failed several different medications. He had bilateral paraspinal botulinum toxin injections in his back and none of this really helped, so he came to us to see if DBS is a potential option. So we really looked at this patient as we do all of her patients as a case-by-case basis. This was our first patient with Huntington's disease that we even considered surgery for, but we decided that because his primary indication was dystonia, that we would go ahead with the surgery. So we implanted a couple of years ago bilateral GPI DBS for this patient and approximately one month after the surgery, we started simulation. Very basic programming parameters to start, but within 2 weeks he noticed significant improvement in his movement, so the result was quite immediate. We did tinker with the stimulation parameters for over six months or so, but really 2 weeks to 4 weeks he was really doing quite well after simulation was initiated. He was able to sit in a chair, he was able to do things with his family, and his quality-of-life really improved.
We repeated several different preoperative scales that we did before surgery, just looking at quality-of-life, patient independence, caregiver burden and we repeated this 2 years after surgery to see if this was a maintained therapy and really his quality-of-life definitely continued to be improved and maintained 2 years out, especially his ability to do activities of daily living, just overall stigma. Independence was maintained, it wasn't necessarily improved because the disease is progressive so we're not dealing with something that's stagnant. So there are things that did get a little bit worse; his independence did get a little bit worse or maintained 2 years later. We also decided to bring the patient back 2 years after surgery and turn the stimulator's office to see what would happen, and within 30 minutes or so after the settings were turned off his movements did come back, although not as severe as before surgery. We repeated different dystonia rating scales and the UHDRS which is a Huntington's disease rating scale, and really the dystonia and the off and the on state was significantly improved, especially in the trunk and his lower extremities. That movement improved as well.
I think the takeaway point for this is that we're not advocating DBS for every Huntington's patient. The patient came to us and he had a primary complaint of dystonia that was really getting in the way of his quality-of-life and DBS is an indication for dystonia so we were going to treat that what the stimulation. Another thing about this particular patient is that his cognition was relatively maintained at the time of surgery. So before surgery his Mini Mental state exam was 28/30, so we took that into consideration as well before we were to implant this gentleman with DBS leads and go through a major surgery like that. Also psychiatrically, he didn't have anxiety, depression, or psychosis before surgery, so we took all this into consideration, and the caregiver support I think is the last thing. He had a great family and support system; brain surgery is not a light surgery so all of those things together made him a good candidate for the surgery. So if people out in the community think of a patient similar to our patient, they should consider DBS.
So our center is very big – we have 10 physicians just focused on movement disorders. So what I do and the few physicians that work with me, we don't actually see the Huntington's patients; we have a separate Huntington's clinic, so if they were to refer us for certain things like that, then yes, we would consider it. The expectations for the patient's is huge to set those expectations. We're not going to cure your disease, we're not going to help your balance necessarily or your chorea, but if you've a primary complaint that we know DBS can help, then sure, we would consider it.