Neuromodulation: A Solution for Painful Diabetic Neuropathy?

[Dr. Dana Dunleavy]
Part of the reason I bring it up is there's so much interest in what you alluded to, which is, can I do it? Right? I think everyone knows no matter what you'd find a way, but some people want to figure out how difficult it is going to be and whether it's Doug Beall's practice or some of my colleagues locally that have built the largest and most successful and highest quality practices. There's something about their prior groups that they felt they were being held back and they could do better by patients by doing it independently. That's why they moved in that direction.

I think that what you provided is tremendous support across the country for anyone that wants to do what you've done. They're not going through that really difficult first year that you did. The billing and the coding is there, all the aspects of finances are now available. There's a lot of mentoring.

The local neurosurgery group, which is world-renowned for endovascular neurosurgery, the chairman was actually let go twice because he was such a pioneer in that world. Now again, they're the leaders. It's very interesting. We recently talked to the founders of TRAVELIER, which is a group of physicians doing interventional radiology to cover underserved hospitals. Again, I think without guidance from you and others, it would be very challenging for them to pull that off.

[Dr. Douglas Beall]
The aspect about being a pioneer, you can always tell a pioneer because he's the guy with all the arrows in his back. There's a lot of truth to that. Doing things out of the box is welcomed by some people, not really welcomed by others. Being at the cutting edge, sometimes there's a sharp hard edge to ride and it works in your favor and sometimes not, but the real advantage I think that all interventional radiologists have regardless of their focus, whether they're MSK, IR-focused or IO or IR vascular, the real secret we have is that we're just great at guiding things under minimally invasive situations, under fluoroscopy, and under CT. We have three-dimensional knowledge, we're able to guide things under cross-sectional imaging very well, and that's not the case for all the specialties. We passed the Bear Bryant Test. When we used to go through the goop and yank somebody out of the rack in the middle of the night, they'd land in the ready position, and we'd pass that test. We'd land in the ready position, ready to guide stuff under fluoro.

Our formative years, we had a bottle in one hand guiding a needle through soft tissue under fluoro or CT with the other. That's where we came from, that's the heritage. That gives you the ability to do this on your own. You go out and if you practice clinical excellence, if you're just better at your job than any other specialty, there will always be a place for you regardless of what you do, where you are, just be better at clinical outcomes. Put the patient first, put your outcomes as a primary goal, measure what you do.

One of the secret things that I've done over the years that's really helped me is that I've been around pegging a square hole for my entire career, and I've had numerous people say, and it's just only abated in the last few years, but, "Oh, you shouldn't be doing that. Why are you doing this? That's not within your specialty, you shouldn't be doing that." One of the things that I've done to deal with that, to mitigate the impact of those statements, is I've measured everything that we've done.

I've run our 58th clinical trial. I've got four registries going on simultaneously now, and what this does is it's a huge advantage because you can say, "If you think I shouldn't be doing this, let me tell you that my average pain score goes from a 9 to a 1.4 after a kyphoplasty. That on the average, our sacroplasty produces a 6.4-point reduction that's better than anything that's been measured in the past five years. Our pain pump people get off their opioids reproducibly.” This collection of data, not only forestalls additional critical comments, but it also allows you to figure out where you are. It gives you your dashboard to figure out how you're doing and how much you're helping people. Also, it's valuable in terms of collecting and publishing level 1 evidence, you really can contribute to the science a lot, and it makes you attractive to industry.

What industry does is, I remember, I'll give you a little bit of inside baseball. We're doing a clinical trial, and one of the sponsors of the clinical trial sent me an errant e-mail, and I got this spreadsheet showing that the Cleveland Clinic was getting reimbursed twice as much per patient as I was. I was pretty mad about that and let it go and just didn't do much about it. I thought about, why in the world are they getting paid twice as much? I talked with my research coordinator, and she said, probably, they just have a lot more steps to go through, and they're probably just a lot more expensive with the bureaucracy. I think that that's probably true, and I talked to the sponsor a little bit about what they were reimbursing. They made the comment that the research coordinator at the sponsoring medical device company said, "Yes, we wish you had a lot more sites like yours because you enroll lots of patients that are appropriate patients for the therapy, and you're a lot cheaper, and things go, in general, a lot faster."

I understood that this is how we do it. We're small, we're nimble, we enroll appropriate patients, we have very little bureaucracy, one signature does it all, and that's why sites like ours are so attractive to industry, pharma, and medical devices. Even the NIH people who review these things because we're doing multiple research projects, we're enrolling lots of patients, and we're getting really great results, and it's not costing a fortune to do it.

[Dr. Dana Dunleavy]
I think many people may not realize how enormous the PDN problem is. When you and I have talked, either with our interventional radiology colleagues that do a lot of vascular work, either venous or arterial, or our discussions with vascular surgeons, we would say that some of our documented numbers, so we talk about 28 million patients in the US with diabetes, 14 million with neuropathy, and about 6 million that probably are appropriate for treatment with neuromodulation based on failed pharmaceutical attempts.

Almost every discussion I have with vascular surgeons who have no reason to feel inclined to do this procedure, say that those numbers are a big underestimate and that the most disappointing aspect of their practice is the fact that they revascularize a patient with critical limb ischemia and the patient's disappointed in them because they still have peripheral neuropathy or diabetic neuropathy.

Number one, I think you've very clearly elucidated just how successful neuromodulation is for PDN. In fact, more successful than failed back surgery or non-surgical back. What about some of the incredible findings of this two-year data about innervation? Can you talk about some of the studies on that?

[Dr. Douglas Beall]
You bet. I'm going to go back half a click in scope and scale this a little bit based on what you just said there, Dana, if that's all right. Typically, we would take people with back or leg pain and we would have about a 50% response rate, and a 50% response rate specifically means for half of the patients, we were able to cut their pain in half. We were able to reduce their pain by 50% in 50% of the patients. That was the typical response rate for tonic stim. Then we've bumped up some of the high-frequency stimulation. We bumped the 50% up to 80%. We're able to cut the pain in half in 80% of the patients.

That was the new level. That was the new area that we were getting to. We would have about half of the patients that were profound responders, which means cutting the pain by 80% or more. If you cut the pain by 80% or more, basically, it's the other term we apply there as a remitter. Because if you have a 1 or 2 out of 10 pain, having reduced your pain by 80%, but that's just pain with life, right? There's effectively no pain at all. If you're complaining about a 1 out of 10, then we can't be friends anymore. That's just the way things go.

We've taken that, we've raised the bar up and about that, we've got 80% for non-surgical low back. We have 80% and almost 60% profound respondents. Those are pretty good. Those are 60% remitter and non-surgical low back, and these are patients that either can't have surgery due to comorbidities or don't want to have surgery based on their own preference. Then, we've taken it to 90% response rate for PDN and most recent data that was released, the tier data. Then, the profound respondents are 65%. I mean, two-thirds of people are remitters, and that's just a tremendous number. This is why we gravitate toward epidural injection for acute radiculopathy. We gravitate for vertebral augmentation, for fractures and we gravitate for high frequency stimulation for PDA because these things just work. They work for sure, patients come back and they're not just like, “Ah, no, I feel a little bit better." They're like, "Oh my God. Thank you, thank you, thank you."

The other thing that's really interesting that I wasn't expecting at all. In fact, I'm not sure I believed the data when it first came out. We tend to be a little bit skeptical, I think it's a healthy skepticism. The data came out to about two-thirds of the people, a little over 60% of the people, had improvement in their neurologic function and their testing, the motor testing, sensory testing, and the reflex testing. The testing was filament testing, and it was standard neurologic evaluation. I'm doing temperature testing, two-point discrimination, and filament testing for one of our research studies now. It's quite painful, takes a while but it's very accurate, and so is this. We found that about two-thirds of the patients had demonstrable improvement in their neurologic function and sensory function. Which is also of course, neurologic, but this is profound. It happens in two-thirds of the patients.

It was so important because there's not any other medication, any other strategy, anything else that I've ever seen that does that. I think this is unique and what is the mechanism? It's the mechanism of action. I don't even want to hypothesize on that. There's a lot of things we could talk about that for an hour, but thank God we won't. We'll just skip to the fact that there's a study specifically focusing on the primary and secondary endpoints or the neurologic function of the patients. If you're able to actually reverse the disease process, and if there's one thing that you could certainly say about painful diabetic neuropathy and neuropathy in general, it's just not reversible.

I held that as a truth for many years, but it looks like it is reversible, at least in a certain portion of the patients. Driving up this morning, I had the radio on and I heard an advertisement for four different neuropathy clinics around the city where I live. It was a noninvasive treatment of neuropathy and I asked, “how about that?”

I'm reviewing a legal case now where one of the non-medical “specialists,” I use the specialist in air quotes, was treating the patient with neuropathy, with things like massage and light therapy and a vitamin or mineral cocktail and some of other things. I think that's all well and good, but it's not going to work. These things and the response rate even to the membrane stabilizers. We've got gabapentin, pregabalin, and you've got tricyclic amitriptyline. You have Cymbalta duloxetine. These things work just mediocre to poor. If you were to put them on a scale of 1 to 10, they work about a three or a four-level of good. Of course, there's no scale for that but I want to give the listeners this to see, to have all of the therapies that you could apply all of them and they still are mediocre to poor outside of high-frequency spinal cord stimulation. That's the only thing that I've found, the single thing, that exists that will improve and reverse the neuropathic changes, the neuropathy changes. It's by far the best thing in terms of symptomatic improvement.

I live in a city of about a little over a million people and much the same as you do, Dana. Why are there four clinics around? It's a small city, four neuropathy clinics, because it's common. You mentioned about six million people with painful diabetic neuropathy. I realize that comes from the CDC numbers, but I think that's a gross underestimate. It seems to be maybe half of those are split between our two cities because there seems to be, PDN just comes in, we should but we don't advertise for it. We just use the mantra if you hurt, come in and see us and we'll figure it out. We're a non-chronic opioid clinic and there are so many good things.

This is an example of one of those things that's non-medications, non-opioid, and for people that are responders, which 90% of people respond well to the trial. It's going to be life-changing for them. It's one of the two things I do that you can actually test before you do the implantation surgeries. The implantation is a surgery, it's a minimally-invasive light surgery, but as a surgeon, you don't want to give people anesthesia of any kind until you deem it necessary. You can do a test drive, a trial, and when somebody gets 90% relief for a chronic unremitting problem, you cannot lock your office door tight enough to keep them out. They will find their way back to you.

This is one of those things, I like it because I don't have to convince, I don't have to give advice. I say, "Here's what it is, here are the numbers where you should be, here is our personal experience with this therapy. Let's do a test drive." By the time they come back to have the leads pulled out, they're like, "Okay, when can I get this schedule? I'm not leaving until I know when I can get one of these put in.” This is, it's been, practice changing and it's for a very common problem.