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Hello and welcome back to the Neuro Transmitters podcast, a show about everything neurology with the goal of reducing your neur a phobia. I'm your host, Dr Michael Ken Trees. And today we're talking about facial weakness. So you may have seen in the news recently that Justin Bieber had put out a video on Instagram showing some pretty profound right, facial weakness and had said that he was recently diagnosed with Ramsay Hunt syndrome. So maybe you're wondering how they came to that diagnosis and how is that different than Bell's palsy? And what can we do about it? Well, let's dive into that assessment a little bit. So facial weakness is not an uncommon symptom. And a lot of times when we're evaluating facial weakness, one of the first questions that we want to answer is this due to a central or peripheral cause, central meaning within the brain, peripheral, meaning the seventh cranial nerve. So, in trying to differentiate central versus peripheral causes of facial weakness, a lot of times we are looking at the forehead, does the weakness involve the forehead or does it spare the forehead and a lot of times a central cause of weakness is going to spare the forehead. And this has to do with the fact that the upper portion of the face gets supplied by both hemispheres. So if one hemisphere like in a stroke is injured, then the other side can still pick up the slack and that forehead on the affected side can still move even though it might be weakness in the lower face or even in the arm or leg as well. Now, moving down to the brain stem level, the seventh nerve nucleus is wrapped around the sixth nerve nucleus. So if we're thinking about a brain stem stroke, it's very unusual, although not impossible that you could get what looks like a facial paralysis or a Bell's palsy from 1/7 nerve nucleus stroke. However, that is usually going to involve some of the neighboring structures and the biggest one of that is the sixth nerve nucleus. So if you also see some differ culti with abducting or moving the eye, then that's going to be more suspicious again for a brain stem stroke. Now, the facial nerve obviously does the movements and muscle control on that side of the face. But it also does a couple extra things including taste to the anterior two thirds of the tongue as well as the nerve to the step EDS, which helps to quiet down loud noises. So those two clues right at the bedside, those can be very useful. So what I like to do actually, if I'm evaluating someone with facial weakness is I'll grab a long, uh long tip, cotton swab and spray a little saline from a syringe on it. Then just dab the side of the tongue on the weak side of the face and ask them, does this taste normal and compare it to the other side? And if there's a market difference in taste that is against supportive of a peripheral seventh lesion. And then the other thing is if you have a tunings fork, great, uh if you don't, you can just rub your fingers just like that and ask them, does it sound louder in one ear or the other? And if it's louder on again, the side of the facial weakness, that is another supportive feature for a peripheral seventh nerve, this can avoid a lot of unnecessary testing um for these patient's, you know, a lot of them end up getting worked up for strokes and things like that and it ends up just being Bell's palsy. But what is Bell's palsy? You ask a great question. So essentially it's an idiopathic seventh nerve, palsy, idiopathic being the fancy medical term for, we don't know, but maybe a virus. So what do we need to check to make sure that we're not missing something? So you should always do in otoscopic evaluation, right? Take a look in the ear canal. And if you see blisters, then that would suggest this is a varicella zoster virus infection or a shingles infection. And that's when we call it Ramsay Hunt syndrome. So, in these patient's, there might not be any blisters anywhere around on the face or the chief. Uh, but if you look in the ear canal, sometimes you'll see some in there. So, like with many things, we want to differentiate Bell's Palsy Ramsay Hunt syndrome from other types of things that could cause facial weakness. The timeline does come into play. Typically, we're looking at hours, a lot of times I've had folks come in after waking up first thing in the morning and they notice their faces week, it freaks them out. Understand. And usually the first thing that everyone is thinking is is this a stroke. But if again, we do our evaluation, we do our exam and we think about it logically were able to put these people down the right pathway a little bit more expeditiously, a little more efficiently. So what are other things that we have to think about? So again, it varies depending on the timeline, but folks who might be at higher risk for Bell's palsy include people with diabetes as well as women in the third trimester of pregnancy with bilateral facial weakness. You definitely want to think about things like Lyme disease, especially if it's endemic to your area. Some autoimmune conditions like sarcoidosis, organ beret could potentially cause weakness like this as well. If it's more of a slow course, a tumor near that area, something called a vestibular schwannoma could also cause facial weakness, although that is usually also associated with hearing loss. So if you are worried about something like that in that more slow, so going timeline, you do want to get an MRI of the brain with and without contrast. And a lot of times you're going to want them to include sequences looking at the internal acoustic canal or the eye a see that way again, if that timeline is on the slower end or doesn't quite fit for Bell's palsy or one of the other similar syndromes, then you can rule out any structural causes of that weakness. But let's talk about treatment of Bell's palsy and Ramsay hunt for that matter. So with Bell's palsy again, right, we don't see those blisters, uh, the vesicles in the ear canal. And so a lot of times folks come in first day or two, we'll usually treat with steroids, predniSONE or something equivalent to that. And there is some debate as to whether antivirals are beneficial or not. Now, with Ramsay hunt, it's a more clear cut case that yes, there is more likely a viral infection going on and we do add in, uh, something like acyclovir which is an antiviral. So we're looking at how severe someone is at the beginning of their symptom and how likely are they to get back that function. So when we're evaluating the degree of weakness from facial nerve palsy or facial nerve injury. Uh We use something called the House Brackman Scale and this goes all the way from grade one, which is essentially normal movement all the way up to grade six, which is total paralysis of the face. In between those two extremes. There's obviously a lot of gray area, but primarily, we're looking at the movement of the forehead, in particular, the ability to close the eye as well as the ability to move the mouth. So those two things are very important, in particular, closing your eye things you don't think about. So, one of the things that people might notice is that they wake up in the morning, their eyes dry or their vision is blurry. And in reality, what's happening is they can't close their eyelid all the way. So we're seeing folks getting dry eyes and that puts people at risk for corneal abrasions and that can get infected and that can be a really big problem. So a lot of times you're having folks use artificial tears during the day and maybe a lubricating ointment at night or just taping the eye closed at nighttime as well. And that way you're able to prevent that injury to the cornea. Other things you might notice is maybe there's difficulty uh closing the mouth when you're eating or drinking. And that can be obviously problematic for a number of reasons, especially in public as the recovery goes on over the next month or maybe even several months, we can start seeing something called sin kinesis, which is essentially where you try and say you blink and maybe the corner of your mouth twitches. And what's happening is as those nerve branches regrow, sometimes they don't go back 100% into the same areas leading to these movements occurring in conjunction with one another in different parts of the face. So talking about recovery rate depends on what set of day do you look at? One study from the BMJ showed a complete recovery rate of about 49% with a median recovery time over 3.5 months. Now, there's another study I also came across that showed Ramsay hunt syndrome tend to have a worse prognosis than typical idiopathic Bell's palsy. So again, not great data on a lot of these things with respect to prognosis, but things that are in your favor is if you don't have a history of diabetes, if you get treatment early within the first several days, um, and a younger age, those tend to be better prognostic factors overall. For facial strength recovery. Those are my quick hits on facial weakness. If you enjoyed this podcast, please rate review and share it on Apple itunes, Spotify or wherever you get your podcasts and subscribe for future episodes. You can reach me on Twitter at Doctor Ken Trees, that's Drkntris or by email at the Neuro transmitters podcast at gmail dot com with any questions or show suggestions. As always, thank you for turning in and we'll see you next time.