James Melville, DDS, an Associate Professor and Oral Surgeon at UTHealth School of Dentistry, talks about Jaw Nerve Repair.
What typically causes a patient to lose feeling in their jaw?
MELVILLE: The typical presentation of someone who comes and sees us for a loss of sensation is either post-ablation, meaning they had a tumor removed, or they have a new cancer that’s eating away at that nerve. Or the third option as that they had a surgery, like a wisdom teeth injury, or wisdom tooth extraction and they had an injury during the process of extraction.
How common is that to happen?
MELVILLE: I would say, for a permanent injury after a third molar extraction, it’s about one in 10,000.
What are the current treatments? How often is it a permanent loss?
MELVILLE: So usually, relatively, third molar extractions are common. And, I mean, it’s done probably all over the place even right now. But to have a permanent deficit, it’s a very low phenomenon. But if you get it, it basically, it’s like winning the lottery in a bad way. I guess in a word it’s terrible because you can’t feel and taste on that side of that tongue. So, it bothers you the rest of your life if you don’t get it repaired. Patients who used to suffer from it would have, from the moment, they would have an injury to the rest or life, be not be able to piece and feel on that side.
What are the current standard treatments for that?
MELVILLE: So the current standard is treatment. Number one would be another nerve site, borrowing a nerve from another site such as your leg or your neck. And the new common modality is using a donor harvested. Basically, a donor nerve, what we call an allograft, and the one that is, what we use is called Axygen Axoguard, and it’s basically a donor graft that’s been sterilized and we can use it to have even better success rates in the autografts. The ones from the patient themselves.
What’s the disadvantages and advantages of getting a graft from a donor versus reusing your own nerve?
MELVILLE: So, obviously, surgical site. So essentially, if you do have to take your own nerve, we have to go down and find a nerve, take it and we’re going to make that site numb. By using the telegraph or the Axygen products, we can essentially use that instead of taking your own body parts and a donor nerve and have the exact same result or even better results, the studies show.
With the nerve graft from the donor, can you walk me through that procedure?
MELVILLE: What we call autogenous graft is essentially… we will consent the patient to, OK, we’re going to repair your nerve that’s been damaged during this procedure by borrowing or taking a nerve from other part of your body. Number one side would be the lower leg. There is a nerve called the sural nerve. We go down and we harvest it and then we can get a good, I would say, about 12 inches, 13 inches out of the leg, and it would involve a scar isolating the nerve and removing a nerve. The bad part of that is, obviously, it’s an incision that’s going to cause a scar. Number two, it’s going to have this side of that area where the nerve is innervating numb. So that becomes another morbidity associated with the surgery, right? So, we’re taking a nerve that was innervating or giving sensation to the lateral foot, and you’re taking that nerve, that’s going to make that numb, and bringing it up with the hope that it’s going to give re-sensation to the area that was damaged in the oral cavity.
Talk to me about Chris. What led him to come to you?
MELVILLE: So, Chris was actually a very unique case because he had ameloblastoma, which is a benign tumor. It comes from the dental follicle. So essentially nothing he did, it’s not anything related with smoking, drinking, environment, or anything like that. It’s just kind of a genetic backlog. These tumors arise from the dental follicle, and they randomly start growing. And so, a rare case, but a tumor basis or a benign tumor basis is probably one of the more common benign tumors that we see all the time. But Chris had this tumor and he basically floated around for multiple hospitals, and, because of his immigration status, he was not able to fully get care anywhere. It was until he came to us at UT Houston, we were able to diagnose him and then we worked with him and he was able to actually get insurance through his work that we were able to proceed with the surgery for removing the tumor and reconstructing him.
What was his recovery like?
MELVILLE: His recovery rate, he had to do a micro-vascular free flap because his tumor was so big that essentially, we did an en bloc resection, removing the soft tissues, the nerve, the bone and having clear margins, and that’s our number one goal as oncologic surgeons. We need to have clear margin, so the tumor does not come back. So, remove that, then taking his lower leg, what we call a micro vascular free flap, we brought that up and then connect, did the micro-vascular in the neck and then repaired his nerve at the same time. So that surgery is pretty extensive. It can take anywhere from 10 to 12 hours. I believe his was on the shorter end, about 10 hours, but 10 to 12 hours. And his recovery from that is usually about three months. Three months where he’s able to fully walk again and have no issues. And then the recovery for the oral cavity is surprisingly faster. It heals up faster than the donor site. Because, obviously, you’re not walking on it all the time. So usually most patients who have similar procedures will feel comfort in the mouth about two months and then full ability to run and do their normal activity from the donor side of the leg about four to six months.
Do they get full senses in their nerve in two months?
MELVILLE: No, I guess not the great thing, just kind of the timeline of it is before we would tell them, once we cut this nerve, we’re never going to be able to repair it. Even with their autogenous grafts, the donor grafts, it just barely was done, but it was about 50 percent or less percentage of recovery. With allograft, the donor nerves, now we give them around 87 to 90% recovery, and those usually take about anywhere from six months to a year to fully recover. Chris got his sensation back around eight to nine months.
What impact can that have for a patient? Because I know when they don’t have that sensation, it just impacts their daily life. After the surgery, how does that change their quality of life?
MELVILLE: The best analogy I can give is if you go to your dentist and they give you a shot and you feel that numbness, right? That fat lip, that heavy tongue and you can’t taste anything. Imagine being, and the first thing for me, personally, I always try to relate to how I would feel… is I want that feeling gone because it can’t taste anything, I’m, like, biting on my tongue. Imagine having that the rest of your life. That would have been his kind of dilemma the rest of his life if we weren’t able to repair it immediately. So, it’s just that heaviness and no sensation. You feel awkward and you just don’t feel yourself the rest of your life. So, it was a great opportunity to give him at the same time the surgery of the reconstruction, bone, soft tissue, the nerve at the same time.
Once they have the surgery, is there any restrictions. Or once they recover, it’s pretty much all good?
MELVILLE: Oh, yeah. So, once they’re recovered, they basically have skin, bone and nerve. So, it’s the full reconstruction and there’s no restrictions. They, obviously, have a plate that’s supporting everything, like a titanium plate. But once your natural body is healed, it is part of you and they have no restrictions or anything. They can go play sports. I mean, they can do football, MMA, soccer, whatever they want. There is absolutely no restrictions. It would act just as the same as a natural mandible. Might be stronger because there is a titanium there, so – there’s metal, so it might be stronger. But absolutely no restrictions.
Anything I didn’t ask you on the allograft that you think that people should know?
MELVILLE: It’s a process, it’s a donor material, about 86 to 90 percent success rate. I think it’s pretty good. It’s safe. It’s FDA approved, so…
And is the surgery covered by insurance?
MELVILLE: It is. At this point. It wasn’t in the past, but at this point, nervous reconstruction is standard of care. So bone, soft tissue, which is skin, and then now nerve. So, it used to be always the reconstruction of bone and soft tissue. Now, with the data we have, part of reconstruction is also the nerve.
So, talk to me about the condition, how common is it?
MELVILLE: So macroglossia, before COVID, was a very rare condition. It was associated with long-term intubation, patients who were exposed to what we call ACE inhibitors. Basically, these blood pressure, and it was also a subset of African American or Black patients that were getting a majority of her kind of before COVID. With the onset of COVID because of the long-term intubation, we’ve seen a spike in it. And relatively from the past, I guess, the whole year with the COVID kind of surrounding our 11 patients total now. Three have sought treatment here, but the rest are around the country and they’ve either emailed me or called me regarding her condition.
Talk about macroglossia, what exactly happens?
MELVILLE: So macroglossia, I mean, from Latin term, it’s enlargement of the tongue, right? Macroglossia; just a large tongue. So, there is some genetic component. Some kids are born with some syndromes, but those tend to be macroglossia’s about not that big, they’re just a bigger tongue. So, what we call a true massive macroglossia is what we’re seeing is when it’s hanging past their chin that’s coming down almost kind of appendage. And those are usually caused by, the two before COVID that I was aware of, was caused by long-term intubation. They had strokes, they went into the hospital, long-term intubations. One had exposure to the ACE inhibitors I talked about, and she was of African descent, and essentially, we really didn’t know why they get it. We can theorize why they have it, more of like a balloon effect, it’s just a reaction. But relatively just a rare phenomenon, easily managed and that still, this was the tricky part because a lot of people didn’t know how to deal with it, but it’s easily managed with a surgical procedure, and we can get their quality of life back to normal. But essentially, it’s just a big, large tongue and we still don’t know the true etiology. The one nice thing about we’re doing here is in the study we’re doing is actually coming to a closure as we are looking at both the genetic and histology aspects of both the previous macroglossia’s that were seen before COVID, then some of the patients that after COVID that was diagnosed with quote-unquote COVID-related macroglossia. We’re calling it now. So, their histology was different then when we compare the two histology of the macroglossia’s. They had more of the similar features that a lot of doctors are talking about, or scientists are looking at of lymphocytic infiltrations that we didn’t see with the macroglossia tissue from before COVID that was just associated with stroke or ACE inhibitors. So, there is something unique about these enlarged tongues that, with COVID that’s causing more of an inflammatory, almost a auto-immune response to it. And so, the study’s looking at both histology and genetics because there is, I think out of 11 patients I’m aware of, 10 of them are African American or Black. So, there is some kind, genetic disposition to acquiring this, but that’s why we wanted to do the study, right? So, look at the genetics, look at the histology, and also look at the clinical features of these tongues.
You said it’s linked to intubation, long-term intubation. How long, usually?
MELVILLE: So, these are long intubations for over two to three weeks. A lot of times, the first thing we kind of try to associate, was it due to the prone position? Because that was a unique thing. They used to do it for a lot of lung issues or people had that can’t, they would turn them on their back or in the front. And instead of a normal prone position, they would do supine position; they would do the prone position. So, we thought maybe it related to the prone but some of these patients were now coming, had a history of being in the prone position. So, it’s just a combination of factors that’s kind of like, why did this happen, right? And that’s why we’re looking at all this.
How does that effect their day-to-day?
MELVILLE: So obviously they’re just stuck home. They’re kind of seen as a unique entity when they walk out the door, right? So, the first thing people see them is their giant tongue and they just kind of get looked on; outcasted. Because of the giant tongue, they can’t talk, they usually are put a tracheostomy, so even if they wanted to talk, they’re breathing through their neck instead of through their vocal cords through their mouth, so they can’t talk. And they can’t feed themselves, so essentially, they have a stomach tube. So can’t talk, can’t go out in public, can’t eat by mouth, so their life quality of life is extremely poor. And that was our first patient that we saw before the whole COVID thing, this was three years ago, the options were, OK, we can give you a surgical option, this has been with you for a year and a half, two years. Your kind of living in a sheltered life, you can’t go out, you can’t eat, you can’t talk. The options are surgery, there are some risks with the surgery, the patient the family was OK with doing the surgery. And once we rooted it, she looked like a normal person and essentially with no ailments. She was able to eat by mouth. She had a stroke, so she had some residual deficits, but she’s able to communicate well. And then, as we progressed, more of those patients, they’re fully able to function as a normal person after the surgery.
And how big does the tongue usually get? Is it twice the size of normal?
MELVILLE: Oh, I would say. I mean, if you look at a normal tongue, it’s almost, like, quadruple the size or bigger than the size of the tongue. And the really odd entity is that a lot of times these tongues, the original macroglossia’s they described in textbooks, they resolve. Once you remove the source that’s causing this, they all kind of shrink back. The ones we find with the massive macroglossia, they you just act like these giant bags and they just scar. From the surgical histology, they’re just covered in scar tissue. So essentially, it’s just a appendage with scar tissue and it will never return back to normal. It’s just, like, hanging. So, if we didn’t operate on them, this would be a lifelong ailment.
And what’s the surgery?
MELVILLE: The surgery itself is relatively, an old surgery. They described there is in the 1940s or 1920s when they first started doing any type of tongue surgeries. But really, it’s a tongue reduction surgery or we call it a modified glossectomy, which is, in Latin terms, is removal of a portion of the tongue. And if you know the anatomy of the tongue, there’s two nerves that come and they’re called lingual and hypoglossal. They come on the lateral aspect of the tongue. The hypoglossal gives motor function, so the ability to speak, and the lingual gives taste, right in the middle is just a lot of soft tissue. And on top of it is sensory buds or taste buds that innervate. So, the surgery is cutting a pizza and we’re avoiding the nerves and just cutting out the meat of the tongue but avoiding the nerves. And then we close it together like this, and that reduces the tongue, at the same time giving them full function or retaining full function, both with the hypoglossal and lingual. So, taste and sensation and mobility is all intact.
How soon does that happen after surgery?
MELVILLE: Usually they’ll know right away. The tongue is swollen from the surgery, but within about a week to two weeks, the tongue is really vasculature, so it heals itself really fast. So, within two weeks, it doesn’t look like you ever had a surgery done.
Anything that I didn’t ask you that you feel that people should know about the condition?
MELVILLE: I mean, just to note, this is a extremely rare condition. I don’t want people freaking out ‘oh, I’m going to catch or get COVID and get this’. Even out of COVID. I actually I had a patient from Germany contacting me via email and her cousin was in Nigeria and they didn’t know how to deal with the problem. And so essentially, I told them just give me an email and I’ll contact, see if I can correspond with her surgeons or doctors. She passed away from the COVID complications before it could happen. But everywhere around the country I tell them the same story, obviously, they’re really sick, they can’t be transported. If they’re stable enough for surgery, this is a life-changing surgery. It’s a very simple surgery. I mean, most oral maxillofacial surgeons, most otolaryngologist and plastic surgeons will be able to do the surgery, and the surgery itself takes about 45 minutes. It’s not a long, complicated surgery either.
Since it’s so rare, is there a number in how rare is it?
MELVILLE: I think, I mean, overall, probably less than .01% of everyone. We haven’t done the calculations, but, very rare.
So, it’s less than one percent.
MELVILLE: Yeah.
Like, anybody that’s been intubated would get this…
MELVILLE: No, no, not at all. No. There are some side reports from, even away from stroke patients and COVID patients, there has been reports of macroglossia associated with neurosurgeons who have their patients in a prone position. But they all return back to normal after treatment and then they get back to their normal supine position. But, yeah, the true massive macroglossia is the one that’s kind of… people are so alarmed about it because it’s something you don’t see on a daily basis or regular, even a yearly basis. So unique. And I would say, I mean, looking at all the textbooks I’ve read over the years, the ones we did at UT Houston are probably the biggest ones I’ve ever even documented in textbooks, so…
And is surgery the only way to cure it?
MELVILLE: There have been a couple groups that have talked, discussed palette, just kind of early intervention. So, they do compressive wrappings, you know like the Ace wraps they do for sports medicine? So as soon as they get that, if they can compress it, I think there’s two cases that’s reported that you were able to retract that tongue back. But what happens is, if you don’t have that right away or if there’s other factors even with that. Anthony, my patient had that done and his tongue did not recede at all. It just kept growing larger and larger. So, I think if you can catch them early enough where patients, if doctors can catch this condition early enough, they can try it. I don’t know if there’s a resolution. But there is something non-surgical they can try. It might not resolve the problem, but at least there are some cases that help shrink it back to normal size with non-surgical options.
0:10:59:>>INTERVIEWER: OK. Thank you.
Interview conducted by Ivanhoe Broadcast News.
END OF INTERVIEW
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