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Cheryl Martin (Host): Hi, I am Cheryl Martin. If you've ever felt electric shock like pain in your jaw, cheek, or teeth, you may think it's time to go to the dentist. But on this episode, neurosurgeon Dr. Sheri Palejwala explains how these mysterious symptoms could point to what's called trigeminal neuralgia. It's a nerve disorder that's often misdiagnosed.

She'll offer tips on how to spot the signs, what questions to ask your doctor, and much more. Dr. Palejwala, thanks for coming on.

Sheri Palejwala, M.D.: Thank you for having me.

Host: I can only imagine that when someone feels sudden electric pain in their face, it's terrifying. So what exactly is that pain and who does it typically affect?

Sheri Palejwala, M.D.: Nerve pain is usually described as sudden, sharp, severe electric, or even burning pain. When this occurs in the face, it can be coming from the trigeminal nerve. The trigeminal nerve is the fifth cranial nerve, and it carries sensory information such as touch, pressure, and pain from the face. Severe attacks of burning pain in the face can be due to trigeminal neuralgia.

 Trigeminal neuralgia is a relatively rare disease affecting only three out of every 10,000 to three out of every thousand people. This large variation in incidence is because the disease is often under or misdiagnosed. It is much more common in those over 50 and two to three times more likely to occur in women than in men, but really can occur at any age. Trigeminal neuralgia is also more common in patients with multiple sclerosis or MS.

Host: Talk about how trigeminal neuralgia differ from other types of facial pain, such as migraines or dental pain.

Sheri Palejwala, M.D.: So trigeminal neuralgia is characterized by sudden attacks of pain in the face in the distribution of the trigeminal nerve. It is often described as the most severe pain known to man. The trigeminal nerve has three different branches. The first one around the eye, the second involving the cheek, and the third at the jaw.

 The pain usually follows only one or two of these anatomic distributions and only occurs on one side of the face. This can be a distinguishing characteristic. The pain of trigeminal neuralgia is typically triggered by light touch, smiling, brushing teeth, chewing, speaking, or even by a light breeze. The most distinguishable aspect of trigeminal neuralgia is the severity of the pain, which can be debilitating, and even in some tragic circumstances lead to self-harm. Migraines can similarly be unilateral or only on one side of the head, but often involve nausea and sensitivity to light or sound. The pain of migraines is not usually triggered by touch of the face and is much less severe than that of trigeminal neuralgia. But dental pain can be a little bit trickier because many teeth come into direct physical contact with the trigeminal nerve, which collects sensory information from the teeth.

The pain can be similar, but is usually associated with some dental findings such as infection or decay. In fact, the overlap in presentation is so significant that most patients with trigeminal neuralgia have already undergone significant dental work, including root canals by the time they're diagnosed.

Host: You have talked and have just given us some of the red flags. What really got my attention was this is one of the most severe pains. What symptoms do people often ignore or misinterpret?

Sheri Palejwala, M.D.: Because of the strong overlap between two much more common diseases, migraines, other headache phenomena and dental issues, most people dismiss their trigeminal neuralgia as migraine pain or dental issues. The truth of the matter is that these diseases do have to be excluded before you can go about diagnosing something like trigeminal neuralgia.

Host: So then do you suggest that a person, if they are having some of these symptoms, then go to the dentist first?

Sheri Palejwala, M.D.: No, I do recommend they start with their primary care doctor, however, their primary care doctor can refer them to a dentist if appropriate. But dental issues do have to be ruled out before we can start to consider trigeminal neuralgia.

Host: Now talk about underlying causes or risk factors associated with trigeminal neuralgia.

Sheri Palejwala, M.D.: So understanding trigeminal neuralgia does require a little knowledge of anatomy, so you'll have to bear with me for a minute. The trigeminal nerve exits from the brainstem and it has a protective lining. That protective lining undergoes a transition period in an area called the dorsal root entry zone.

 This space is only three to 10 millimeters long. Primary trigeminal neuralgia is caused by a loop of an artery that is abutting this sensitive area of the nerve, and with every beat of the heart, this artery hits the nerve where it's at its weakest point, and it gradually wears away at the protective lining.

 This can lead the nerve to send false signals of severe pain to the brain. Secondary trigeminal neuralgia can also be caused by pressure on the nerve, but it's caused by something else anatomic, such as a tumor or a cyst, or even multiple sclerosis that leads to attacking and disintegrating the protective lining around the nerve.

Host: So is there anything a person can do to prevent this from happening to them?

Sheri Palejwala, M.D.: The phenomenon that surrounds why some people get trigeminal neuralgia and others don't, is difficult to understand. Some people might have a loop of this artery in this region, but don't have any symptoms, and other people may not have this anatomic finding and still have the symptoms. But there's nothing that anyone does.

It's considered to be an anatomic variant in the case of primary trigeminal neuralgia and secondary trigeminal neuralgia is thought to be secondary to a tumor, a cyst or MS.

Host: So why is trigeminal neuralgia often misdiagnosed? And you talked about it can be confused or people think it's migraine or dental pain. And what can patients do to advocate for the right diagnosis?

Sheri Palejwala, M.D.: So one issue is that there is no lab test or imaging study to definitively diagnose trigeminal neuralgia and it's diagnosed by symptoms alone, after ruling out these other confounding conditions. It requires the patient who has classic findings and clearly and consistently describes their symptoms to a healthcare professional who is aware of the symptoms and picks up on it, and then refers that patient to a neurologist.

As a result of this tricky diagnosis, many patients suffer for years before they're appropriately diagnosed. And so the only thing we can really do is continue to raise awareness so that it's in the back of the mind of primary care physicians and patients alike.

Host: So what are the treatment options available for trigeminal neuralgia and what limitations do they have?

Sheri Palejwala, M.D.: The first line treatment of trigeminal neuralgia once diagnosed is anti-seizure medications, specifically oxcarbamazepine or Trileptal or carbamazepine or Tegratol. These are medications that are prescribed by neurologists and taken daily for prevention and may require gradual dose titration or increases in order to provide adequate symptom relief.

These medications, like all treatments, have side effects, including dizziness, headaches, imbalance, nausea, and even more serious issues like electrolyte abnormalities. Those who don't have adequate symptom relief from these medications or can't tolerate their side effects, may require more aggressive management.

 That's where I come in as a neurosurgeon. The most effective next option is surgery that I get to perform called a microvascular decompression. The goal of this surgery is to physically separate the loop of that superior cerebellar artery away from that trigeminal nerve in its sensitive area, the dorsal root entry zone with a small pledget.

 About 90% of patients are pain free after this type of surgery and the rest with significant pain improvement, and that relief occurs within hours or days after surgery with a very low rate of pain recurrence. Surgery can even be repeated for those with incomplete pain control or recurrence.

 For those patients for whom surgery may not be safe, another option is a percutaneous rhizotomy. This is a minimally invasive outpatient procedure where a trajectory is taken through the cheek and the nerve is agitated by compressing it with a balloon, a chemical called glycerol or radiofrequency waves. This works by disrupting the pain signals from getting back to the brain.

 Working similarly to the way you might rub your shin after bumping it. The touch sensation overrides the pain signals, and there is often more facial numbness from this type of treatment modality, and the relief can last up to five to 10 years, but the procedure can also be repeated as needed. The last treatment option is high dose radiation called radiosurgery to that vulnerable area of the nerve, the dorsal root entry zone.

 Radiosurgery is great for people who have many medical issues and may be poor candidates for surgery or for those with atypical or secondary trigeminal facial pain or pain from MS. It can often take a few weeks or months to experience some pain relief, and about 60% of patients are pain free with a relatively low recurrence rate.

Host: So life can really feel normal again if one chooses one of these options.

Sheri Palejwala, M.D.: Yes. The silver lining is that people can have significant long-term relief of their pain, and there's all these options. And if one treatment modality doesn't work, particularly the invasive ones, you can often repeat the procedure or jump to a different treatment procedure such as someone who's had a rhizotomy can still go on to have a craniotomy for microvascular decompression. As a minimally invasive skull-based neurosurgeon, microvascular decompressions are one of my favorite surgeries. I get to take someone who's usually quite desperate and miserable and watch as they discover this new pain-free life. These are the patients who often smiled in years as moving the face triggers the pain, and it's incredibly gratifying.

Host: I can only imagine. So, for someone who's been living with this pain for months or even years, someone's listening and thinking, this sounds like what I've been going through, and maybe this is a first they've heard of this. What should they do next? What questions should they ask their doctor and what type of specialist should they ask for?

Sheri Palejwala, M.D.: So the first step after seeing your primary care doctor and if there is a clinical suspicion for trigeminal neuralgia is to request a referral to see a neurologist. Neurologists can then perform the appropriate workup to start ruling out other similar diseases and obtain a diagnosis of trigeminal neuralgia.

 This workup may require lab work and often requires an MRI of the brain. If they've already tried medications for years without much relief. The next step is to request a referral to a neurosurgeon. In these circumstances, age, health, or fear shouldn't really preclude the referral to a neurosurgeon as there's many minimally invasive and non-invasive treatment modalities that can provide lifelong and sometimes life-saving relief.

Host: So what questions should they ask the doctor, whether it's primary care or the neurologist or the neurosurgeon?

Sheri Palejwala, M.D.: Primarily if they think their symptom profile and the distribution and episodes of pain do represent classic or primary trigeminal neuralgia.

Host: Any other questions for the doctor?

Sheri Palejwala, M.D.: It's really a clinical diagnosis. It's made by the pattern of symptoms. Again, it would have to be unilateral pain that's described as sharp, hot, burning, and electric in the distribution of the trigeminal nerve. It's very anatomically based and so many people might think they have certain pains, but we might notice, well, it crosses the boundaries of the trigeminal nerve or it doesn't include the entire territory of the nerve.

And in those circumstances, a different diagnosis might have to be considered, but it's really the clinical and anatomic pattern.

Host: You shared with us the different treatment options. So should someone come in and say, do they ask the doctor which option they recommend, or do they do their homework and say, I've been looking at these and I'm wondering if this one would be better for me?

Sheri Palejwala, M.D.: When patients come in to see me, they've already failed medical management. And so now we're looking at their, our more invasive options. I will go through the three main options, percutaneous rhizotomy, craniotomy and radiosurgery, and I'll explain to them how long they can expect to be pain free with each of those options.

How robust their pain relief will be, how long it will take to achieve that degree of pain relief. And then we'll talk about the invasiveness of each procedure. Generally speaking, surgery is going to give you the longest degree of pain freedom, and the most robust pain freedom. However, it is the most invasive.

So as long as someone is healthy enough to withstand this type of surgery, that's usually the first line. If someone is medically unhealthy, say they have cardiac issues or are much older, we might recommend a percutaneous procedure or radiosurgery. The problem with radiosurgery is that sometimes it can take a little bit longer for pain relief, and often by the time patients come to us, they've already suffered for so long and so they're desperate for more sudden pain relief.

Host: Doctor, where can people learn more about the Memorial Care Neuroscience Institute at Long Beach Medical Center?

Sheri Palejwala, M.D.: They can visit memorialcare.org/lbneuro

Host: And find there the experts that you mentioned. Correct?

Sheri Palejwala, M.D.: Correct.

Host: Great. Dr. Sheri Palejwala, thank you for educating us on this neurological disorder and the treatments that are available. Very detailed. We appreciate that. Thank you.

Sheri Palejwala, M.D.: My pleasure.

Host: Again, to learn more, visit memorialcare.org/lbneuro. If you found this episode helpful, please share it on your social channels and check out the entire podcast library for other topics of interest to you.

This is Weekly Dose of Wellness, brought to you by Memorial Care Health System. Thanks for listening.