Welcome to UAB MedCast, a continuing education podcast for medical professionals, providing knowledge that is moving medicine forward. Here's Melanie Cole.

Melanie Cole (Host): Welcome to UAB MedCast. I'm Melanie Cole. Joining me is Dr. Marshall Holland. He's a neurosurgeon and an assistant professor at UAB Medicine, and he's here to highlight facial pain classification and treatment.

Dr. Holland, thank you so much for being with us today. As we get into this conversation, what are the different types of facial pain we're discussing here today?

Dr Marshall Holland: Well, thank you, Melanie, for having me today. We're going to focus on different types of facial pain that I end up seeing in my clinic that may or may not be surgically related, but important to determine the diagnosis. As with all things in medicine, diagnosis determines what you do next, which may or may not include surgery.

Melanie Cole (Host): So then, let's start with the definition of trigeminal neuralgia as we get into all the different types. How common is this? I mean, it seems to be the most widely known. Tell us just a little bit about it.

Dr Marshall Holland: I think that's a great place to start. As you said, it is one of the most widely known or at least discussed types of facial pain, but it actually is quite rare. Trigeminal neuralgia occurs in about one in 10,000 people compared to other diagnosis of facial pain that may end up being seen in my clinic. And I think that comes from the lack of understanding, or just lack of overall education on facial pain within our medical system, I'm constantly learning new diagnosis and how to spot them as I proceed through my clinic and my career. But as I've gone along in my career, I've found that trigeminal neuralgia is a very specific diagnosis, a very specific story. And if it doesn't follow that specific story when talking to a patient, I really got to put my thinking cap on and say, "What else could this be?"

Melanie Cole (Host): That's a great point and it leads me into my next question pretty well. So, I'd like you to speak about how patients present with facial pain and why diagnoses must be accurate, because there are other conditions that could mimic the same, correct?

Dr Marshall Holland: That's correct. So I'm going to go back to trigeminal neuralgia and what I mean by this is a very specific diagnosis and a very specific story. And with all of these diagnoses for facial pain, the most important thing I can do as a clinician is sit down and just listen, take a good history about the patient's presenting symptoms, locations, type of pain, because trigeminal neuralgia, as I've found, is a very specific story. These patients typically have a memory of the first time they ever had pain. They'll describe that pain as fleeting and extremely painful, worst pain they ever had in their life, electrical. Commonly, people say, it feels like, "I stuck my finger in a socket, but it's hitting me in my face." Pain's always in an area of the trigeminal nerve, which services sensory for the forehead, the cheek and the jaw, and that pain doesn't extend beyond those areas. Patients will describe that pain as, "When I'm in pain. It's the worst awful pain. But if I'm not in that pain, I'm pain-free." Patients typically will have what we call pain-free intervals, they have bouts of this pain say for a week or two, where they'll notice "I can trigger this pain with brushing my teeth, wind hitting my face." But after those couple of weeks, pain goes away and that can pain can go away for months to years.

Often, this pain's unilateral. It's very rare to see this on both sides of the face. And then, patients when they do become evaluated by providers and they tell this story, they'll start on a classic medication for trigeminal neuralgia, typically gabapentin or carbamazepine and they'll have a significant response, life-changing response, where they say, "I can go back to my normal life." Those key points of the history and specifically the response to medications in my mind says, "This is a true trigeminal neurology patient." If there's parts of the history or a lack of response to medications, where they say, "It took the pain edge off, but not, say, a significant response where I could go back to living my life," I start thinking this could be something else.

Melanie Cole (Host): So when you say you're interpreting the pain and since that can be somewhat subjective, how important for other clinicians is it that they understand what's really going on? Because as you said, when you try the gabapentin, but misinterpretation of the pain can lead to incorrect diagnosis or, you know, treatment mismanagement, so how do you determine that with your patients?

Dr Marshall Holland: A lot of it is listening and starting to ask probing questions searching for an alternative diagnosis. One of the most common diagnosis that I see, and this is far more common in the general population, is temporomandibular dysfunction disorder. And this is a disorder can occur in up to 15% of the general population at some time during their life and is involved with the muscles of chewing, the muscles of mastification. And the jaw apparatus. This is a strong mimicker of trigeminal neuralgia. And often, patients will come to my clinic with a preliminary diagnosis of trigeminal neuralgia and leave with a suspected diagnosis of temporomandibular dysfunction disorder. I say suspected because this is a diagnosis that requires, diagnosis evaluation and treatment by a dentist. My role is the neurosurgeon is to say, "This isn't trigeminal neuralgia, but I believe it's this other diagnosis, far more common, and we need to get you to the right person so you can really get some help and improvement in your pain."

Melanie Cole (Host): Dr. Holland, is it understood that often facial pain syndromes and mood disorders can coexist and that results in an important psychosocial burden. How is that addressed with the patient to ease that burden of the pain and anxiety over something that maybe even hasn't been diagnosed?

Dr Marshall Holland: You know, this is extremely important from a global pain management for this patient. And I believe my role and as a surgeon is to try and get to that diagnosis so they can head down the road of "This is going to get better. This will get better. We've just got to get to that right diagnosis and get you to the right person." Typically, particularly this last diagnosis, I just brought up temporomandibular dysfunction disorder, these patients have seen several providers, gone through several rounds of medication or other invasive treatments. By the time they get to a neurosurgeon's clinic and.. And oftentimes, there can be dismayed that I tell them, "Look, there's nothing I can do surgically for you, I think you need to see this one more person." And sometimes I'm left to convince them that, "I'm not trying to get you to someone else just to get you out of my office, but this is the right person. This is what you've been searching for that's really going to be able to sit down and help you."

Melanie Cole (Host): Such an important point. So tell other providers listening why that need for good relationships, and as you've stressed in this podcast, the importance of listening to the patient's story fully, and the comprehensive multidisciplinary approach when dealing with facial pain.

Dr Marshall Holland: This is key, because I can only offer my few surgical approaches. But if I'm the person during this evaluation that can get again to that diagnosis and get them to the right provider, we can get these patients the relief they need. And by listening and having a framework in your head of what else could this be if this doesn't follow that standard pattern of trigeminal neuralgia, you can ask the right probing questions. Temporomandibular dysfunction disorder is described as a mimicker of trigeminal neuralgia, because they will have these spikes or crescendoing of pain that can be triggered, talking, eating, touching the face. But one of the key differences that a patient may offer or you may need to ask is they'll have a secondary pain that's constant and in the background that can wax and wane throughout the day, throughout the week, different times in their life. And it's far more likely to be bilateral. So I start to hear these words or I ask the patient to describe their pain, I'll start searching for other clues, this may not be trigeminal neuralgia, what else could it be? These patients will also typically have areas of pain that are outside the area serviced by the trigeminal nerve in terms of its sensory division. And these can be big clues to something else may be going on here, and the surgical procedures I do may not help this patient.

Melanie Cole (Host): Before we wrap up, give us a brief overview of the surgical procedures that you do that might help people with facial pain and when you feel it's important for other providers to refer their patients to the specialists at UAB Medicine.

Dr Marshall Holland: I believe for a trigeminal neuralgia, this is a lifelong disorder that patients will be dealing with if this is a true trigeminal neurology patient. And medications, like I said, could be life-changing. This typically gives patients back control of their life. However, these patients' disease will push through, the natural history would say that, and they often get to the point where the medications are causing cloudiness of thought or balance difficulty due to the high dosage. And this is where surgery plays a role. We call this medication refractory trigeminal neuralgia.

There's different approaches to it. The most invasive, but the most durable is a microvascular decompression where it is a brain surgery where we approach the trigeminal nerve, and we may or may not see a vessel compressing the nerve. If we see strong compression, we decompress that, place some padding between the vessel and the nerve. And this can be curative for the patient's pain on average about 10 years. If we don't see a vessel, then we will intentionally comb the nerve and create a lesion or numbness of the face. And the idea behind this is to prevent those triggers that we talked about earlier. This also incredibly has the same half life in terms of its durability, about 10 years. But it does come with a higher risk profile, and so this is something that we talk about in my clinic with the patients.

Another surgical intervention that I consider is radiofrequency lesioning and this is an outpatient procedure where we place a stimulating probe through the cheek, down to the base of the skull where the nerve exits. It's done under sedation, intermittent sedation. We're able to wake the patient up just enough to interact with them to determine which branch of the trigeminal nerve we're stimulating. And then, we use microwaves through the end of the probe to lesion the nerve. One thing that's nice about this procedure is it's an outpatient, but it's not quite as durable. The halflife is about half of a microvascular decompression, about four and a half, five years. Half the people will have recurrence of their pain. But this procedure can be repeated. And for some patients, they have trouble wrapping their head about undergoing a big brain procedure, this feels less invasive to them, and so this can be a strategy to control their pain. And when I say halflife for both those two procedures, I mean, no pain, no medications is our goal.

The third procedure that I also perform for my trigeminal neuralgia patients is stereotactic radiosurgery. This is done in conjunction with the radiation oncologist, where we lesion the nerve using radiation. This can be a good option for patients that are extremely risk averse, because this does not involve any, intervention other than a trip to the radiation center.

And then, there are other types of pain that we haven't got to beyond trigeminal neuralgia and temporomandibular dysfunction disorder, that are more rare such as postherpetic neuralgia. This is a patient who's had shingles of the face and the lesions are treated with an antiviral. And despite the lesions going away, they have continued burning and constant pain of the face. One of the unique procedures that I am offering for those patients is a trial of stimulation of the trigeminal nerve branches. And for some patients, this can provide up to 50% relief. And even with that 50% relief, they can get part of their life back. This is also a strategy that we employ for patients that have non-intentional injury to a trigeminal nerve branch, and will have essentially neuropathic pain of one of the branches of the face or multiple branches, this we call trigeminal neuropathic pain.

So, overall, facial pain, the more and more I learn about it, and I believe other providers learn about it, can be a very deep and difficult subject to tease out an exact diagnosis. The most important thing in anything in medicine is the diagnosis determines our next steps in terms of workup and treatment.

For providers out there who are struggling with a patient trying to determine what type of facial pain this could be, or it doesn't fit the mold of that classic trigeminal neuralgia patient, always happy to see them in my clinic and work through their history and try to determine a diagnosis and, most importantly, a treatment plan.

Melanie Cole (Host): Thank you so much, Dr. Holland. What an informative overview of facial pain syndromes. Thank you so much for joining us. And a physician can refer a patient to UAB Medicine by calling the MIST line at 1-800-UAB-MIST or by visiting our website at uabmedicine.org/physician. That concludes this episode of UAB MedCast. For updates on the latest medical advancements, breakthroughs in research, follow us on your social channels. I'm Melanie Cole.