[Lauren DiNardo] Hi everyone, my name is Lauren DiNardo and I'm a second year medical student at the Jacobs School
of Medicine. Today, I'm talking about vocal cord paralysis and medialization thyroplasty.
So, to start with some larynx anatomy, the structures we want to keep in mind and focus on
today's talk are the thyroid cartilage, which is on the front of your larynx and also a little bit on
the back, as you can see here; and then your false vocal cords, which are important for protecting
your larynx; and your true vocal cords, which are important for phonation. So, when we breathe in, our
vocal cords are open, allowing air to pass into our lungs. And when our vocal cords close, that's
when we're actually speaking, and the increase in pressure in your larynx causes vibration,
which creates a sound as known as phonation. So, I have a video to demonstrate this.
[YouTube video] (various mouth sounds)
So, what causes vocal cord paralysis? Typically, the vocal cord is supplied by the recurrent
laryngeal nerve, and typically, this nerve is damaged, which creates a hypomobile or immobile vocal cord.
And, this is caused by, typically, eradogenic damage, so damage caused by a medical professional,
inadvertently, and 46% of the time it's due to surgery. And, the left nerve is more
commonly injured then the right, as we'll see. It can also be injured by a neoplasm, so lung
malignancy compressing the nerve, or idiopathic, no apparent cause.
So, your recurrent laryngeal nerves are wrapping around structures, that's what
recurrent means. So, the branches of the vagus nerve and the right recurs around the subclavian artery,
while the left recurs on the aortic arch. And so, your left is more prone to injury, as we said,
because of its longer descent into the chest, so surgeries are more likely to run into this and
lung malignancies or any cancer in the chest can compress this. So, a vocal cord paralysis, like I
said, is when your vocal cord is hypomobile or immobile due to that damage to the nerve.
And, you can see in this far right picture here, that if your vocal cord is paralyzed, when your
vocal cords are attempting to close to speak, one cannot move inward remedially, and you cannot
create that pitch that you were trying to create. So, if you have unilateral vocal cord paralysis,
you're more likely to present with dysphonia, difficulty speaking, and dysphagia, difficulty
swallowing. Or, if, whereas if you have bilateral vocal cord paralysis, you're likely to present with
an obstruction and you'll often need an intubation or tracheostomy to create an open airway.
So, how to operatively treat vocal cord paralysis is medialization thyroplasty,
and the goal of the thyroplasty procedure is to regain closure between the two vocal cords.
And, that's my placement of an implant. So, as you can see up here, you're going to place the implants
medially, or inwardly displace your vocal cords so that you can regain that closure and phony.
And, the procedure starts with the incision in your neck at the level of thyroid cartilage,
like we pointed out, and you're creating a window at the level of the true vocal cords,
which is where you'll place your implant. So, when you can place the implant, you push it medially,
and you can push back your vocal cords together, and you're able to speak again. And so, the cool
part about this procedure is that it's not under local anesthesia. So, once your implant is placed
you can recheck the voice and adjust the implant based on the pitch or the tone of voice you want.
And, you can also go in with the laryngoscope and make sure that you're actually regaining
autoclosure in the middle of the procedure and allows for adjustments. So, I did a research project
on the complications of medialization thyroplasty, and we looked at the CPT code 31591 and surveyed
the National Surgical Quality Improvement database by the American College of Surgeons from 2017-2019.
And, the complications we found are on the right here, and what's important to know is that we found
12 overall complications in seven patients, and we looked at over 300 patients. So, this procedure has
a fairly low complication rate and is really great at improving phonation from vocal cord paralysis.
So, in summary, vocal chord paralysis is typically caused by
surgical damage the left recurrent laryngeal nerve and medialization thyroplasty is
an effective surgery to treat vocal cord process and has a very low complication rate.
These are my references, and thank you so much for watching!