The neurosurgeon at Marcus Neuroscience Institute, Baptist Health, provided perspective on invasive procedures for degenerative conditions and when deep brain stimulation is needed.
As society continues to age, many in the medical workforce believe that the number of individuals with Alzheimer disease (AD) and Parkinson disease (PD), the 2 most common neurodegenerative disorders, is expected to rise. These complex, multi-factorial diseases each present with several different challenges, headed by a limited treatment landscape. Over the years, some patients with more severe forms of these diseases have opted for invasive surgical procedures, mainly deep brain stimulation (DBS).
DBS, which uses a surgically implanted, battery-operated medical device, has been a promising approach to treating disabling symptoms such as dystonia, epilepsy, essential tremor, and PD. While it’s not indicated for AD, there are ongoing trials assessing this approach. Similar to a heart pacemaker, DBS delivers electrical stimulation to specific areas in the brain that control movement, which blocks the abnormal nerve signals that cause symptoms.
As part of a new iteration of NeuroVoices, Julie Pilitsis, MD, PhD, MBA, neurosurgeon, Marcus Neuroscience Institute, Baptist Health, sat down to discuss the landscape of invasive procedures to treat degenerative disorders and the advances in DBS. Pilitsis, the first women neurosurgeon to become a dean, provided perspective on the patient conversations when deciding surgical procedures, the advantages and benefits they bring, and whether new therapeutics being introduced will have an impact on clinical decisions for these procedures.
In contrast to some of the other surgeries I do or have done. if somebody has a brain tumor that's causing them problems, there's a conversation about removing the brain tumor, and treating cancer. With deep brain stimulation, it's a very personal decision. This shared decision making is really important. They don't come to me, and I don't say “you need this.” I say “why do you want this?” And then we try to figure out if I can deliver the reason why they want this. If somebody has tremor, and they aren't getting relief from medication, or if they have stiffness—these huge peaks and valleys, and wants more predictable ON time, the time when they're feeling good, those are all good reasons to do this. If somebody wants their swallowing to get better, or if they want to be like they were before they had Parkinson disease, this is not a great reason to do this. This is important. Because it's a quality of life procedure, shared decision making is exceptionally important.
I say to my patients, nobody wants brain surgery if you don't have to have it. We start there with that point. But oftentimes, the patients that I'm seeing, their diseases affect their life, they are not getting out of their house, they are taking medications 6-8 times a day with unpredictable responses. Overall, their life quality is not good. When somebody gets to that point, the chances of trying one more medication and making a market difference, is unlikely. We have many more medications for Parkinson disease than we do for essential tremor. For essential tremor, we have about 2 [treatments], and we try a variety of other things with less effect.
If you’re getting to the point where you're trying to, eat or drink and you're spilling on yourself, you're embarrassed that you're not going out, you can't write a letter or write anything down on a piece of paper, this is a time when you have to consider this. The next piece in this conversation is: I’m at the point that I want to do something more than medication, what should that be? For some people, deep brain stimulation is the answer. For other people, focused ultrasound may be the answer. Even for a different set of patients, doadopa or a pump that infuses medication may be the answer. In some cases, it’s none of the above. But those are some of the conversations we have.
In medicine and in life, everybody changes their perspective from one way to the other over a 20 year period. We used to do thalamotomies or pallidotomies, which were the first brain surgeries for essential tremor or Parkinson. That was an invasive procedure where we burned a hole in the brain. Deep Brain Stimulation was much more exciting because you weren't damaging the brain, and you could treat both sides. The problem with thalamotomy and pallidotomy was that you could only operate on one side. Now, in this 20-year pendulum, we're at the point where we’re talking about the improvement in this technology so that you could potentially use this external treatment—focused ultrasound—not just for one side like you could for thalamotomy in the past.
The jury is kind of still out a bit. A good example is we used to offer subneurosurgical procedures for migraine. With the advances of CGRPs (calcitonin gene-related peptides), that has virtually gone away because they are so effective. That was kind of a game changer in the neurologic space for the dynamics of surgery. I don't think we have that yet in Alzheimer disease or Parkinson disease, for that matter.
I think we're eager to see where that goes. Another exciting thing that I need to mention is that just recently here in South Florida, we opened up the blood brain barrier in a patient with Alzheimer disease using focused ultrasound. Focused ultrasound can make that ablation in the brain, but it can also be used to change the permeability of the layer that protects the brain, meaning that some of those drugs that and therapies that may not have worked because not enough was getting in with systemic side effects, can now get in. That’s another way to look at the interface between it invasive, device, and pharma based therapies.
Transcript edited for clarity.