Transcription:
Understanding Vocal Cord Paralysis

Scott Webb (Host): Vocal cord paralysis in children can affect their voices and cause difficulty in breathing, exercising, and eating. And joining me today to help us understand the causes, symptoms and treatment options is Dr. Karthik Balakrishnan. He's an Associate Professor of Otolaryngology at Stanford University and Lucile Packard Children's Hospital.

This is Health Talks from Stanford Children's Health. I'm Scott Webb. Doctor, this is a really fascinating topic. We're talking about vocal cord paralysis today. So, as we get rolling here, what are some of the common symptoms of vocal cord paralysis?

Karthik Balakrishnan, MD (Guest): So, generally when we think about the voice box and the vocal chords, there's three key functions that everybody has to do. The first is making a voice and that's the kind of most obvious thing with the vocal chords. And so the vocal chords should close to make voice, but the vocal chords also have to be able to close when we swallow.

Because that's one way that our body prevents things from falling into our windpipe when we swallow. So, it's really critical. And the vocal cords also have to be able to open because if they don't open, you can't get air flow into your wind pipe. And then it's very hard to breathe. So, the symptoms that people have when their vocal cords are paralyzed are basically related to one of those three functions not working correctly or more than one, so they can have voice problems. So a hoarse voice, a breathy voice, or a weak voice, or sometimes what we would call vocal fatigue as the day goes on and they use their voice more than they kind of lose their voice. Typically we see that when one of the vocal chords is not working. You can also see difficulty with choking and coughing, especially with drinking liquids because things are falling into the airway. And then in young children, especially if both vocal chords aren't working and some children can be born with that, then you can have a problem where the airway is obstructed and they have noisy breathing or squeaky breathing. They work really hard to breathe and therefore they may have trouble feeding as a result, or they may have trouble gaining weight and growing. So, those are some of the common symptoms that we might see.

Host: Yeah. And so when we talk about the causes, what are the most common causes of vocal cord paralysis?

Dr. Balakrishnan: So, again with that, we have to divide it up into one vocal cord not working or both vocal chords not working. If one vocal cord is not working, then anywhere between a fifth to a third can be related to birth. Children can be born with that. And often that's simply related to how the child is positioned in the birth canal, for instance. But, it can also be increased by things like use of forceps. Which, you know, sometimes it's just unavoidable, but sometimes the consequences that can be that one of the vocal chords, it doesn't work. Other common causes would be surgery of the heart or the big blood vessels coming off the heart because the nerves to the vocal cords run down into the chest before they come back up to the voice box so they can get stretched down in the chest during those surgeries. Surgery on the thyroid gland, surgery on the windpipe or esophagus, for instance, things like tracheoesophageal fistula repair in young babies can do it.

And then airway reconstruction surgery, which I, and my colleagues do a lot of, can also put the nerves to the vocal chords at risk. When it comes to both vocal cords not moving, then it's a little different, that's more often something that child is born with. Or sometimes it's related to a thing called a Chiari malformation where the lower part of the brain kind of drops down a little and the nerve centers that control the vocal cords get squashed and then the vocal chords don't work.

Host: So, how does the team decide if a patient needs treatment for vocal cord paralysis?

Dr. Balakrishnan: So, the first thing we do is to take a really detailed history because often there are clues in the history that can suggest that vocal cord paralysis or vocal cord mobility problems are contributing to the person's symptoms. In clinic, we very often will also do what's called a flexible laryngoscopy. And that involves directly visualizing the vocal chords by using a skinny camera that looks like a spaghetti noodle, and it goes in through the patient's nose. And we can actually look down at the voice box and watch the vocal chords move while the patient talks. Sometimes we'll also actually watch the vocal chords move while they swallow.

Those are some key pieces. Sometimes we also use ultrasound and that's a growing area of interest. Our team, and a few other teams in the country are leaders in this area where we can actually use ultrasound to assess vocal cord motion. It's not quite as sensitive right now as putting the camera in the nose, but it's still a very useful tool in some cases.

And once we confirm that one or both vocal cords is not working, then we've got to think about what are the consequences. So, that's where maybe evaluating the swallow with a swallow study, might be useful, evaluating the breathing by looking at the airway under anesthesia, for instance. There's a variety of things that we can do, but if we identify a significant compromise of one of those key functions, breathing, swallowing, or voice, then those are people who are going to need treatment.

Host: Yeah. And so let's talk about that. When we talk about treatment and the options, what are the options that are available for vocal cord paralysis?

Dr. Balakrishnan: Um, that's a really good question. There are a lot of different options. For some people, we expect that they're going to recover movement to that vocal cord over time. And one really common example of that is children who have a weak vocal cord or paralyzed vocal cord after heart surgery. The vast majority of these kids recover over a few months.

And so what we have to do is temporarily help them. So, in those situations, what we'll do sometimes is inject a little bit of filler material into the paralyzed vocal cord to move it closer towards the middle, so that the other vocal cord that is working can come across and meet it better and close better. And that can help both with voice and swallowing. In other cases, where we think that there's going to be a more long-term deficit, we can do more permanent procedures. And sometimes that involves bulking up the vocal cord, more permanently with some sort of filler injection or an implant, or the patient's own tissue in some cases.

And sometimes it involves what's called a reinnervation where we actually borrow a nerve from elsewhere in the neck and hook it up to that vocal cord. And that does not restore movement, but what it does is it restores muscle tone and bulk, and a better position for the vocal cord, so that the cord that is working can come across and meet it.

Now, when we're talking about both vocal cords not working, the problem is more that the airway is obstructed because the vocal chords are closed. And so in that case, we have to create space. Sometimes we'll use stitches and things to pull the vocal cords apart. Sometimes we have to do an endoscopic procedure where we actually enlarge the airway either by splitting the cartilages of the voice box and spreading them apart or by splitting them and putting a little piece of rib cartilage in there to hold the vocal cords apart so that there's more space to breathe. And in that case, we of course have to balance the need to improve the breathing and create space with the desire not to compromise the voice or swallow too much by pushing the vocal chords too far apart.

Host: So, then Doctor, how might vocal cord paralysis affect children over the course of their life? You know, you mentioned that a lot of times, the treatment options are temporary because it's going to sort of resolve itself. But I guess I'm wondering, does it always resolve itself, do all the treatment options, are they always effective? And just generally, how will this affect children over the course of their lives?

Dr. Balakrishnan: That is a tricky question. It depends in large part on the child and kind of what they decide to do with their lives. And that's really something we have to consider a lot when we think about kids, you know, when we see a young baby, who's both vocal cords are not moving. They have airway obstruction our first priority right then is to get the airway open and to get them breathing so they can feed and grow and develop. But later on when they become teenagers or adults, their priorities may be different and they may not be happy with their voice or their swallowing function. And we may have to do something to correct things back a little bit. But the success rate in general, if we're thinking about the success rate as well, improving the voice or the swallow or breathing or wherever the deficit is at the time that we evaluate the person initially; the success rate is very high.

And again, many of these kids will recover on their own if it's a one-sided paralysis, you know, even up to 70% will recover on their own, given time. Whereas if it's both, it's more like 50%, but a good proportion. The rest of them, there are, again, a lot of different things we can do, and we always just have to work with the patient and their family to balance those priorities of voice, breathing and swallowing based on what's going on in their life right then.

Host: Yeah, I see what you mean. And of course, as you say, patients, people's priorities will change, likely over time. So it's very individualized to the patient. This is really fascinating Doctor. As we wrap up here, what are your takeaways when it comes to vocal cord paralysis?

Dr. Balakrishnan: I think the first thing. is that especially in children, vocal cord paralysis and other airway problems can copy each other in terms of their symptoms. There's a lot of overlap between a lot of different conditions. So, if parents have any concerns about their child's voice or breathing or swallowing, they should get checked out by their pediatrician and get a referral to an airway specialist, like an otolaryngology doctor, an ear nose, and throat doctor.

Another important takeaway is that there is hope. There are many things we can do to help with these problems. And we work with the patients and their families to figure out kind of what's the right choice for them, but it really involves balancing all those functions of voice, breathing and swallow and making sure that we don't kind of throw the baby out with the bath water as we focus on one of those problems.

Host: Yeah, I see what you mean. And interesting topic. And as you mentioned, you know, a lot of times these things resolve themselves and the outcome, success rate is very good, but people's priorities may change. And so there's a lot to factor in here, but as you mentioned, reaching out to primary is a good place to start, pediatricians. And then, you know, seeing a specialist if necessary. So doctor, thanks so much for your time and expertise today and you stay well.

Dr. Balakrishnan: All right. Thanks so much, Scott. You stay well.

Host: To learn more, check out our website at aerodigestive.Stanford.Children's.Org. And if you found this podcast to be helpful, please be sure to tell a friend and subscribe rate and review this podcast and check out the entire podcast library for additional topics of interest.

This is Health Talks from Stanford Children's Health. I'm Scott Webb. Stay well, and we'll talk again next time.