Indications and Candidates for Trigeminal Neuralgia Surgery

Podcast Transcript

Alex Rae-Grant, MD: Neuro Pathways, a Cleveland Clinic podcast for medical professionals exploring the latest research discoveries and clinical advances in the fields of neurology, psychiatry, neurosurgery, and neuro rehab.

The trigeminal or fifth cranial nerve is one of the most widely distributed nerves in the head. Its three branches conduct sensations from the face and oral cavity to the brain. When trigeminal neuralgia is present, the neuropathic pain that results from the disorder can be extreme and sporadic. It can cause sudden burning or shock-like pain that can be absolutely debilitating.

In today's episode of Neuro Pathways, we're addressing the challenging diagnosis and treatment of this debilitating condition, also referred to as tic douloureux. I'm your host, Alex Rae-Grant, neurologist in Cleveland Clinic's Neurological Institute. I'm very pleased to be joined by Dr. Emad Estemalik, head of the section of headache and facial pain and a staff neurologist in Cleveland Clinic's Neurological Institute. Emad, welcome to Neuro Pathways.

Emad Estemalik, MD: Thanks for having me.

Alex Rae-Grant, MD: First, let's start with a couple of easy questions. Where are you from and how did your career land you at Cleveland Clinic?

Emad Estemalik, MD: I was born and raised in Egypt. I lived there most of my life. Six years I lived actually in Germany as well, so I started in Germany, then lived in Egypt. I moved to the US in 2008, did residency and fellowship here at the Cleveland Clinic. It was too good to leave, and I stayed here as staff as of 2013. I've been here since.

Alex Rae-Grant, MD: It's a pleasure to have you with us.

Emad Estemalik, MD: Thank you.

Alex Rae-Grant, MD: Well, let's begin kind of broad. Tell us about the prevalence of trigeminal neuralgia. Who gets affected and what other concerns can present with this?

Emad Estemalik, MD: Trigeminal neuralgia is actually not a very common disease. If you look at prevalence, maybe four to five out of a hundred thousand get affected. It affects women more than men for a reason we really don't know, and it is a disease of the elderly. Now, when it occurs at any age it usually warrants a very thorough workup. In young patients we worry about disease like multiple sclerosis. In elderly we worry about brain tumors, for instance. Any time we have a presentation of trigeminal neuralgia, we right away got to think of a secondary cause until proven otherwise.

Alex Rae-Grant, MD: Obviously there are a number of causes for facial pain and getting a correct diagnosis is critical. I guess can be challenging.

Emad Estemalik, MD: Correct.

Alex Rae-Grant, MD: Tell us about how your team works these patients up initially and determine if trigeminal neuralgia is present or if it's something else.

Emad Estemalik, MD: The first task is always to ensure that the diagnosis is correct. We often see referrals where trigeminal neuralgia is the diagnosis, but we find something completely different. You already elaborated on the presentation. Typical trigeminal neuralgia presents with episodic, sharp, shooting, burning-like, pain within a distribution of the trigeminal nerve. Patients are usually pain free in between episodes. The pain is usually aggravated by chewing, eating, teeth brushing. It affects usually the second or third division of the trigeminal nerve. Often we see patients that were labeled as having TN, but they're diagnosed actually very different.

What is the main differential for this kind of presentation? There is some very distinct headache types that can mimic trigeminal neuralgia. We call those the TACs or trigeminal autonomic cephalgias. For instance, presentation like cluster headache is sometimes mistaken for trigeminal neuralgia because the pain can be sharp, quick, and then it just goes away. Then there's another presentation that comes on like shorter-lasting neuralgia form attacks which are SUNCT and SUNA. These are also very quick stabbing sensations in the V1 ophthalmic division of the trigeminal nerve. When we make the actual diagnosis of TN, then we can go to the next step. The next step is always to ensure that the right workup has been done.

I cannot stress enough the importance of brain imaging when it comes to making the accurate diagnosis. It's not just any type of brain imaging. We really look for sophisticated brain MRIs, things with CISS cuts or FIESTAs where we can identify any compression for the trigeminal nerve at its entry, at the pons level, at the Meckel's cave, to see if there's anything compressing there. However, one important aspect when we get the brain imaging is to exclude the secondary cause. Things like a multiple sclerosis is always on our list, especially in young patients. Certain brain tumors at the serpentine angle are also quite common to cause that. Often we see metastatic brain lesion as well that's already found its way at the
Meckel's cave and causing some sort of trigeminal neuropathy or trigeminal nerve pain as well. That is usually the most important aspect when it comes to approaching the disease at the presentation.

Alex Rae-Grant, MD: Like all centers at the neurological Institute, you lead a multidisciplinary team of specialists, and they share in the care of these patients. Talk me through the medical and procedural modalities that you may use with your team.

Emad Estemalik, MD: The way we look at it is, we always like to have the patient first seen in our headache section by one of our headache specialist or neurologist to, again like I said, to ensure the accurate diagnosis has been made, the workup has been concluded. Then, more importantly, is for the patients to exhaust all a pharmacological treatments and procedural treatments before really sending them to a neurosurgeon. We work closely with the neurosurgeons, even when they see the patients first, in having them first come to the headache section, get the right workup, exhaust all the treatments.

Then at a later point when, for instance, the treatments are not working anymore, then we can discuss the surgical approach. Now, the vast majority of patients do respond to the initial treatment, so that is the good news. Now, some of these drugs that we use, things like seizure meds, antidepressants, skeletal muscle relaxants, though they work, they often have side effects. It's really trying to work with the patient on the best medical option. There are certain procedures that are very simple, things like trigeminal nerve blocks, botulinum toxin injections, that can also provide pain relief. Our goal is really to exhaust all these options before going to the next step, or the last step, which is usually the surgical intervention.

Again, we have a group of physicians, neurologists, headache specialists, and surgeons that work really closely together in really setting the treatment plan. The one thing we always tell our trigeminal neuralgia patients, this is a chronic illness. We are not going to cure this right away, and the likelihood that it's going to be there is very, very, likely.

Alex Rae-Grant, MD: Are there some factors that would lead one to think about moving to the surgical and more procedural side of things? I mean, patient factors, how much medicine they've tried, how long it's gone, any kind of indicators that you guys use?

Emad Estemalik, MD: For young patients, we often try to avoid surgery as much as possible because there is a high recurrence rate with any type of procedure. Patient's age, comorbidities, play a huge role. What kind of surgical option would also be available to them? What are the surgical options? The most prominent surgery and one of the most successful surgeries, is the microvascular decompression. For the MVD, or microvascular decompression, to be an option, there is something very important that we always need to identify first. That is if there is an actual vessel compression that is identified on the MRI. The most common offending vessel tends to be the scar, or the superior cerebellar artery, followed by a vein. Again, if we find that offending vessel, and it's very evident on brain imaging, that is usually an indicator that the microvascular decompression, should it be appropriate for the patient, would be an indication.

Let me talk about some of these surgical options. Again, the MVD is the only nondestructive surgery that is performed. The surgeon usually performs a retro mastoid craniotomy. It's done, of course, under general anesthesia. They expose and then retract the cerebellum until they have the trigeminal nerve really visible, and then they can decompress the nerve. Patients usually spend two to three days in the hospital, then they're out. The vast majority of patients do really well. Initial pain relief, somewhere around 95 to 100%, so they're really good at five year, 10 year. The numbers are also really good compared to some of the other procedures.

Now if, for instance, we don't find that offending vessel or the patient is not appropriate for such a surgery, the other procedures that I call the less invasive, which are things like Gamma Knife or glycerol injections, which also work well for patients. Again, the likelihood of recurrence with some of these other procedures tend to be higher than the microvascular decompression. What is Gamma Knife? It's a form of radio surgery where the patient actually wears a helmet, and then the surgeon radiates the nerve. Depending on the amount of radiation, they can really reduce the pain as well. This kind of procedure doesn't come without a risk. Some patients with more than one Gamma Knife, for instance, or if the radiation is too high, can develop a condition called anesthesia dolorosa, which is a permanent destruction of the nerve. That can give the patient permanent pain. We're very cautious in terms of not only which procedure or surgery we choose for the patient, but how many procedures or surgeries can the patient have.

Alex Rae-Grant, MD: How do you guys determine in an individual patient which way you're going to go?

Emad Estemalik, MD: Every patient is, like you said, it's an individual approach. What we do is really a team approach. As neurologists and headache specialists, we communicate about every patient with our colleagues in neurosurgery and see what the best option is. We always want to ensure that whatever treatment modality we identify is going to benefit the patient for the longest time before we really get to the surgical approach.

Again, other factors that we also put in consultations is patient's co-morbidities. If we identify any psychological or psychiatric disorders that are associated, we have a group of psychologists that really help patients with such a chronic illness and chronic pain disease to cope better with this. It's really a very, very, interdisciplinary approach that many team members play a role in.

Alex Rae-Grant, MD: I understand that your surgical throughput has increased somewhat in the recent years.

Emad Estemalik, MD: Correct.
Alex Rae-Grant, MD: Tell us how you brought the medical and surgical specialists together to really move things along for people in need.

Emad Estemalik, MD: This is a decision we took where we really identified the key players in our operations when it comes to handling this patient population better. What we found is, if we can triage these patients correctly from the beginning and direct them to the right physician early on, they would have a much better chance of being managed in a better way. That would involve our nursing teams, our administrative teams that really play a role looking at every patient, setting out long-term treatment plan, and then identifying where this patient needs to go. Not every patient needed to see a surgeon right away, for instance.

The ones that saw us and we could identify right away that they would be surgical candidates, we accelerated and we improved their access to the neurosurgeons right away. It really comes down to a very thorough triage process that we created and when we started this actually in 2018, and we have even seen not only a higher number of patients that were triaged, but also our surgical volume went really up. That meant that we did a really good job identifying the right patients and helping more patients get to see us that typically would have not been able to do that before.

Alex Rae-Grant, MD: In closing, let me ask you for any final thoughts, or things that your team has learned, that you can share with our listeners about treating patients with trigeminal neuralgia in their own practice?

Emad Estemalik, MD: I think the most important aspect about trigeminal neuralgia is, we always have to be very upfront about the chronicity of the disease with the patients. I always tell patients that right up front it's not a curable disease. We manage it, we can get the pain under control, we can improve the quality of life dramatically, but the likelihood that this disease will be chronic and permanent is very high. Setting the expectations early on really helps the patient understand the disease better and adhere to the treatment modalities that we offer.

The second aspect is really the workup. I mean, the right workup is always very essential. Getting the right brain imaging. It always has to be at brain MRI with and without contrast, an MRI Circle of Willis and, again, as I mentioned before, certain thin cuts that need to be there so we can really identify the vessel compression early on. Then, the third aspect is patients should never be referred to a surgeon right away. Our surgeons are in complete understanding and we're all on the same page that this should always be the last option. If the disease, of course, again at an early age, repeated surgeries or procedures can actually be counterproductive. Patients need to exhaust the medical options, procedural options, before really going to the surgical route at the end.

Alex Rae-Grant, MD: Well, Emad, I appreciate you taking the time to talk us through this challenging condition. I certainly hope our listeners do as well enjoy this. Thank you for joining us on Neuro Pathways.

Emad Estemalik, MD: Thanks for having me today.

Alex Rae-Grant, MD: This concludes this episode of Neuro Pathways. You can find additional podcast episodes on our website, clevelandclinic.org/neuropodcast, or subscribe to the podcasts on iTunes, Google Play, Spotify, SoundCloud, or wherever you get your podcasts. Don't forget you can access real time updates from experts in Cleveland Clinic's Neurological Institute on our Consult QD website. That's consultqd.clevelandclinic.org/neuro or follow us on Twitter @CleClinicMD. All one word. That's at C-L-E, Clinic M-D on Twitter. Thank you for listening. Please join us again soon.