Vagus Nerve related Cervical Dysphagia and Laryngeal – Laryngotracheal stenosis – Problems of the voice
Ross Hauser, MD.
Are voice changes part of a myriad of symptoms that point to vagal nerve dysfunction and cervical spine instability?
This is the story of someone who reached out to us. Their email has been edited for clarity.
Hello, I am suffering from various signs of vagus nerve degeneration. Orthostatic intolerance, insomnia, anxiety, sensitive eyes, GERD, rashes, brain fog, ADHD, fatigue, joint hypermobility and joint pain, memory issues, not digesting food, Meniere’s disease, weak upper body, voice changes, and more. I had a digital motion x-ray done which shows that I have cervical ligament laxity and a 39% loss of my cervical curve. I am hoping that I can be treated.
As we will see below, many of the problems of voice can be traced to a damaged vagus nerve whether through injury or the stretch and compression on the nerve caused by wandering and out-of-place cervical vertebrae.
This article is a companion work to these articles on our website:
- Cervical disc disease and difficulty swallowing – cervicogenic dysphagia
- Vagus nerve compression in the neck: Symptoms and treatments
- Hiccups, Cough, Neck Pain, and Vagus and Phrenic Nerve Injury
- How do voice problems develop in relation to vagus nerve injury? “My voice sounds raspy and I get very tired of talking.”
- Are voice changes part of a myriad of symptoms that point to vagal nerve dysfunction and cervical spine instability?
- What do doctors know about Laryngotracheal and Laryngeal stenosis?
- You have been diagnosed with Laryngotracheal and Laryngeal stenosis and yet, you do not fall within these categories. Where are your answers?
- Chiari malformation.
- The problem with talking and singing.
- The problems of cervical fusion surgery
- The problems of vagal nerve stimulators.
- Vagus nerve innervation of the larynx.
- The intrinsic laryngeal muscles are responsible for controlling sound production.
- Glossopharyngeal and vagus nerve dysfunction.
- The functional dynamics and possible solutions to speech and swallowing difficulties.
How do voice problems develop in relation to vagus nerve injury? “My voice sounds raspy and I get very tired of talking.”
Difficulty swallowing, the inability to breathe properly, and changes in voice, notably hoarseness, are among the most distressing symptoms a person can have. If normal imaging scans and videoscopes do not find any obvious structural cause, then, the “ground zero” of cause should suspect and focus on vagus nerve injury and cervical spine instability.
Let’s start our article with voice changes. What can cause it? In some cases, it can be surgery. This is the story of someone who reached out to us. Their email has been edited for clarity.
I had herniated discs with impingement of the spinal cord at C5-6, C6-7, and C7-T1. Surgery was performed at C5-6 and C6-7 to fuse and replace the discs, I am now experiencing painful headaches at the base of my skull, my voice is altered and it hurts to talk sometimes, jaw pain, ringing in the ears, and sometimes numbness in the lower left lip and the tip of my tongue. A swallow test found no evidence of the abnormal function of swallowing or vocal chord dysfunction. I am under the care of a chiropractor and that is helping relieve pain but voice issues continue. I have also been losing weight, about 4 pounds a month. I have not been trying to lose weight.
Is it anxiety? This is the story of someone who reached out to us. Their email has been edited for clarity.
I have seen my primary doctor multiple times in the last two months. I experience a sensation that there is something in my throat when I swallow, also my throat feels very dry and my voice sounds raspy and I get very tired of talking, I have been experiencing little headaches. This has been going on for the last 5 months. My doctor thinks this is anxiety but I have been taking medication for anxiety and these symptoms do not go away.
What do doctors know about Laryngotracheal and Laryngeal stenosis?
In the US National Library of Medicine’s STATPEARLS (1) Updated January 2022, doctors write:
“Laryngotracheal stenosis is a narrowing of the upper airway between the larynx and the trachea with potentially devastating consequences, including respiratory failure, cardiopulmonary arrest, and death. The upper airway is comprised of the larynx, glottis (the area of the larynx where the vocal cords are), subglottic region (the area below the vocal cords to the top of the trachea), and trachea. . .
Laryngeal (more focused with blockage at the larynx) stenosis may occur as a result of trauma, related to endotracheal intubation, or due to a neoplasm (cancer or tumor growth), autoimmune (Sjogren’s syndrome, Lupus, etc), or infectious process. It can be asymptomatic or can lead to symptoms of upper airway obstruction.
Laryngeal narrowing from any cause calls for a multidisciplinary approach to management, including, but not limited to, pulmonologists, intensivists, otolaryngologists, gastroenterologists as well as speech and language pathologists, and cardiothoracic surgeons. The determination of the etiology of the laryngotracheal stenosis is critical as it can drive the management and provide prognostic information to the patient.”
You have been diagnosed with Laryngotracheal and Laryngeal stenosis and yet, you do not fall within these categories. Where are your answers?
The problems of Laryngotracheal and Laryngeal stenosis are limited in the medical research to those medical conditions described above and congenital abnormalities such as (congenital subglottic stenosis), injury impact to the throat, strangulation, neck injuries, burns from inhaling flames, or the digestion of caustic products. Yet, we hear different stories and different suspected causes.
People will often contact us with their medical history surrounding a Chiari malformation. They will tell us a story of Chiari malformation diagnosis, their neurologists taking a wait-and-see approach to try to avoid surgical management, and the person’s worsening of symptoms. Among these symptoms were neck pain, headaches, and breathing problems. As symptoms continued or worsened, shortness of breath and difficulty talking became more apparent. People will also note a barrage of tests that revealed nothing and their doctors starting to believe that their neurologic-like problems were entering into psychiatric-like problems. Especially when the person reported problems with throat closure, especially at sleeping, difficulty breathing, and the development of terrible and loud snoring. Occasionally someone will report to us that their larynx feels like it has become detached or loose. When they try to sleep on their back, their larynx is blocking their airways.
The problem with talking
Many people who contact us are seeing speech pathologists for what some describe as a weak tongue. Some have an elevated hyoid bone (see my article on forward head posture for a discussion on the hyoid bone) that their doctors believe to be the cause of the “stuck in the throat sensation,” or the “someone is choking me” sensation. They would also tell of times their throat closed completely for a few terrifying seconds.
The problem with singing
We do hear from people who were vocalists. They, like other professionals including athletes, exercised to develop their vocal range. We will occasionally hear a story of someone who damaged their vocal cords in their pursuit of a singing career and this caused severe and significant problems beyond the inability to sing, which for these people would have been devastating enough.
The larynx, or voice box, is involved in breathing, producing sound, and protecting the trachea against food aspiration. The larynx houses the vocal folds and manipulates pitch and volume, which are essential for phonation. The larynx is located in the anterior (front) neck at the level of C3-C6. The muscles of the larynx are innervated by the vagus nerve. When the vocal cords are abducted, air can enter the lungs, and we can breathe. When the vocal cords are adducted, sounds are produced, and we can speak. The vocal folds (cords) must also be closed when swallowing so food does not “go down the wrong pipe.”
This is an email that was shared with us. It has been edited for clarity.
At the age of 19 (now I’m 25), I decided I wanted to become a professional singer, but because I had been learning and using incorrect vocal techniques for years, at some point I injured something in my throat that caused me unbearable burning pain at the right side of my larynx, around my vocal cords. No ENT doctor could ever tell me what was wrong with my throat, my vocal folds looked fine every time I’ve been to the doctor. I’ve done all the necessary tests that doctors told me to do and they didn’t find anything. Fortunately, at some point (after struggling with pain for 1.5 years) I managed to correct my vocal technique step by step and I found some teachers who were able to help me, as opposed to my former vocal coaches, who had taught me an abusing technique.
The burning pain started to go away after practicing with a better technique for 6-7 months. As I was practicing with my new knowledge, sometimes there was a setback and I had to stop vocalizing because I started to feel a strange, unfamiliar irritation, like my vocal folds would slap or clap together very aggressively. As a result, my voice suddenly cut out, felt like I was choking for a moment, and I started to cough during the exercises. After then, it gradually became an issue and there was one concrete day when I felt it very intense, but I didn’t stop, I ignored it. It was one of my worst decisions. It turned into a permanent condition, which I can’t get over ever since. I can’t continue singing anymore. Whatever exercise I’m trying to do, even the simplest ones, I can feel coughing and choking sensations intensify, and I can’t make any progress. I also have issues with my joints, especially in the last year that make the quality of my life worse and worse. By watching your videos, I’m wondering if I was born with unstable joints and maybe the same applies to the ligaments, tendons, and cartilages in my larynx. Now, I have chronic pain in both my knees, elbows, and shoulders, I even have “costochondritis-like” chest pain and I’m only 25.
As soon as I start doing anything, my joints start to hurt and I can’t make any progress, I can’t gain any strength, any muscle. The same applies to my throat, so when I start singing or doing simple vocal exercises, I can feel pain, and choking sensations which intensify if I carry on, so I begin to wonder if there’s any connection between the pain inside my joints and the pain, strange sensations inside my larynx.
In the last 2-3 years I’ve also felt many strange sensations in my whole body that nobody can explain. I’ve always had that typical forward head posture. I tried to work on it, like doing chin tucks for instance, but as soon as I do them I can feel a sharp, pinprick-like pain in my neck. I get unexplained dizziness as well when I do this, so I wonder if I have cervical instability. (the problems of cervical instability as discussed below). See also my article Ehlers-Danlos Syndrome, Atlanto-axial Instability, and Craniocervical Instability.
The problems of cervical fusion surgery
Many people have voice issues after Anterior Cervical Discectomy and Fusion. For some the post-surgical problems resolve after a few months, for others, the return of their “natural” voice is more changing. A December 2021 study in the journal Cureus (3) demonstrated: that “voice parameters in patients who underwent Anterior Cervical Discectomy and Fusion worsened significantly after the surgery compared with patients who underwent Posterior Cervical Decompression and Fusion; however, these changes recovered within three months postoperatively. The possible causes for these findings include the retraction of the vagus and the recurrent laryngeal nerve, postoperative edema of strap muscles, intubation trauma to the vocal folds, and other laryngeal structures.”
The voices of many patients returned
I want to draw attention to the cause of these problems as retraction of the vagus and the recurrent laryngeal nerve and that when the injury to these nerves healed, the voice in many patients returned. This concept is cervical spine stability treatments. If the cervical spine vertebrae can be held in proper alignment by strengthened cervical ligaments, the natural voice can return.
The problems of vagal nerve stimulators
Vagus nerve stimulation can be used as adjunctive therapy for drug-resistant epilepsy or seizures.
In August 2022, (4) Doctors at Texas Children’s Hospital and Baylor College of Medicine reported on a case history where implanted vagal nerve stimulators caused voice problems. They wrote of this pediatric case: “Implanted vagal nerve stimulators (VNS) are an accepted therapy for refractory seizures. However, VNS has been shown to affect vocal fold function, leading to voice complaints of hoarseness. (the doctors presented) a case of intermittent VNS-related vocal fold paralysis leading to dysphonia (abnormal voice) and dysphagia with aspiration (food entering into the lungs) in a pediatric patient. Of note, in this case, is that the doctors pointed out: “While the majority of cases of vocal fold movement impairment associated with VNS have been noted to have a medialized (surgically moved) vocal fold with VNS activation, we describe a case of intermittent vocal fold lateralization (one side) associated with VNS activation. . . ” When the VNS was on, voice measures were performed demonstrating decreased phonation time, lower pitch, and decreased intensity of voice. . . concern with swallowing difficulties and food being aspirated into the lungs.”
Vagus nerve innervation of the larynx
The caption of this illustration reads Vagus nerve innervation of the larynx. The superior laryngeal nerve divides into two branches, the internal laryngeal branch which enters the larynx in the thyrohyoid membrane. The second branch, the external laryngeal, supplies the cricothyroid muscles. The recurrent laryngeal nerve innervates all the intrinsic muscles of the larynx except the cricothyroid muscle which is innervated by the superior laryngeal nerve. Vagus nerve input to the laryngeal muscle is necessary for proper swallowing and speech. Vagal nerve injuries can limit vocal nerve function, affecting the voice including pitch quality and power. Symptoms of vagopathy (vagus nerve dysfunction) affecting the larynx can be chronic coughing, difficulty swallowing, hoarseness, and loss of singing voice power.
The larynx, or voice box, is involved in breathing, producing sound, and protecting the trachea against food aspiration. The larynx houses the vocal folds and manipulates pitch and volume, which are essential for phonation. The larynx is located in the anterior neck at the level of C3-C6. The muscles of the larynx are innervated by the vagus nerve. When the vocal cords are abducted, air can enter the lungs, and we can breathe. When the vocal cords are adducted, sounds are produced, and we can speak. The vocal folds (cords) must also be closed when swallowing so food does not “go down the wrong pipe.”
The intrinsic laryngeal muscles are responsible for controlling sound production.
The intrinsic laryngeal muscles are responsible for controlling sound production. Cricothyroid muscles lengthen and tense the vocal folds, as occurs with talking. Posterior cricoarytenoid muscles abduct and externally rotate the arytenoid cartilages, resulting in abducted vocal folds—this is the position of breathing. The only muscle that opens the vocal folds so air can enter from the larynx to the lungs is the posterior cricoarytenoid muscle, and it is innervated by the vagus nerve. If both posterior cricoarytenoid muscles are not working from a bilateral recurrent laryngeal nerve injury, the person can have a very difficult time breathing. The illustration below may better graphically explain this:
The caption reads Vocal cord paralysis. Recurrent laryngeal paralysis leaves the vocal cords abducted. The recurrent laryngeal nerve is a branch of the vagus nerve from the nodose ganglion which sits right in front of the atlas (C1).
All muscles of the vocal cords are innervated by the recurrent branch of the vagus nerve except the cricothyroid muscles, which are innervated by the external laryngeal branch of the superior laryngeal nerve, another branch of the vagus nerve. A patient with a lesion in the laryngeal portion of the vagus nerve will most likely complain of a hoarse voice, difficulty swallowing (dysphagia), and choking when drinking fluids. There can be a loss of the gag reflex or the uvula deviating away from the side of the lesion because there is a failure of the palate to elevate on that side due to a loss of strength of the levator palatini muscle.
The proper functioning of the larynx is critical for life itself. It is involved in swallowing, breathing, eating, coughing, vomiting, and other vital functions. The sensory receptors in the larynx are innervated by the internal branch of the superior laryngeal nerve with cell bodies in the nodose ganglion. There are many laryngeal neurologic reflexes that function during crises to keep the larynx open or closed. All these reflexes are primarily dependent on the vagus nerve.
When the larynx does not open normally, air cannot get into the lungs.
When the larynx does not open normally, air cannot get into the lungs. This life-threatening situation is called fixed laryngotracheal stenosis, an umbrella term for luminal compromise at the level of the larynx, subglottis, or trachea. What we see with cervical spine instability and upper cervical spine instability caused by cervical ligament weakness is intermittent laryngeal stenosis, which can be missed on laryngoscopic examinations. The word “instability” denotes changeability by definition. Even an intermittent inability to control the opening of airways can permanently change a person’s singing or talking voice and be very anxiety-provoking when breathing. Patients can have trouble breathing or feel like they must “think” to breathe. When the history of examinations prove normal, the neurology of the vocal cords must be considered, which would lead to the vagus nerve.
Swallowing difficulties, and dysphagia, can also be related to the vagus nerve. Swallowing is a complex process involving 3 phases and the coordinated interactions of a network of nerves and muscles. For proper swallowing to occur, the palate and larynx must be elevated, so food does not aspirate into the nose and lungs, respectively. Both processes require the vagus nerve.
In the US National Library of Medicine’s STATPEARLS (2) Updated January 2022, doctors write:
“It is imperative to understand the neuroanatomy of the true vocal folds to understand vocal fold paralysis. The vagus nerve innervates the larynx and its associated muscles. The vagus nerve is comprised of nerve fibers that arise from the nucleus ambiguus (a group of large motor neurons) in the medulla portion of the brainstem. Upper-motor cortico-bulbar neurons (simply among the nerve network that supplies the trigeminal, facial, and hypoglossal nerve nuclei) originate from the cerebral cortex and descend to synapse onto these lower-motor vagal nerve fibers, which originate from the nucleus ambiguus. (Simply again, tracing the network).
After arising from the brainstem, the vagus nerve then exits the skull base at the jugular foramen. It descends into the neck to give off three main branches (the pharyngeal branch, the superior laryngeal nerve, and the recurrent laryngeal nerve. The superior laryngeal nerve supplies sensation to the larynx above the glottis and innervates the cricothyroid muscle. The recurrent laryngeal nerve descends further into the neck, loops around the subclavian artery (on the right) or the aortic arch (on the left), and ascends back up into the neck in the tracheoesophageal groove, where it enters the larynx posteriorly, near the cricothyroid joint. The recurrent laryngeal nerve innervates all remaining intrinsic muscles of the larynx including the posterior cricoarytenoid, inter arytenoid, lateral cricoarytenoid, and thyroarytenoid muscles.”
What are we seeing in this illustration?
The caption reads The three phases of swallowing. The vagus nerve is involved in all three phases of swallowing as it innervates most of the pharynx and larynx mucosal surfaces as well as the muscle that elevates the palate and causes the larynx to contract.
The dangerous route of the recurrent laryngeal nerve and how it may get injured
Let’s look again at the image above. In the May 2023 update of the publication STATPearls (5) medical guidelines housed at the National Library of Medicine, doctors from Aventura Hospital and Medical Center write of the dangerous, possibly injury-causing path the recurrent laryngeal nerve takes.
“The recurrent laryngeal nerve (RLN) branches off the vagus nerve (cranial nerve X) and has an indirect course through the neck. It supplies innervation to all of the intrinsic muscles of the larynx, except for the cricothyroid muscles, as well as sensation to the larynx below the level of the vocal cords. The right recurrent laryngeal nerve branches from the vagus nerve (cranial nerve X) around the level of T1-T2 loops under the right subclavian artery traveling posteriorly and moves back up through the neck. The left recurrent laryngeal nerve arises anteriorly at the level of the arch of the aorta and loops posteriorly under the aortic arch and back up through the neck. Overall, the anatomical course of the recurrent laryngeal nerve is important to understand as it shows the many areas that the nerve might be injured.”
The injury is in the form of impingement whether stuck between bones or compressed by blood vessels.
The image below is a depiction of the normal course of the vagus and recurrent laryngeal nerves. The image comes from a November 2019 paper (6) authored by doctors at the University of Rochester Medical Center and the Mayo Clinic, Jacksonville who in looking to explain the differential diagnosis for hoarseness, noted that hoarseness can be caused by many problems including surgical injury or cervical compression injury to the recurrent laryngeal nerve.
Glossopharyngeal and vagus nerve dysfunction
Glossopharyngeal and vagus nerve dysfunction are typically the cause of chronic dysphagia when no structural lesion is found. The glossopharyngeal nerve innervates the stylopharyngeus muscle, which elevates the larynx and pulls it forward during the pharyngeal stage of swallowing. This action also aids in the relaxation and opening of the cricopharyngeus muscle. Along with the vagus nerve, it provides innervation to the upper pharyngeal constrictor muscles.
The glossopharyngeal nerve also mediates all sensation, including taste, from the posterior one-third of the tongue (the facial nerve is responsible for the anterior two-thirds). It also carries sensation from the velum and the superior portion of the pharynx. A lesion in this nerve can unilaterally impair the gag reflex.
The vagus nerve is responsible for raising the velum, as it (along with the spinal accessory nerve) innervates the glossopalatine and levator veli palatini muscles. The vagus nerve innervates the intrinsic musculature of the larynx. The spinal accessory nerve innervates the palatopharyngeus muscle, which depresses the velum and constricts the pharynx. It is responsible for vocal fold adduction during swallowing. The vagus nerve also innervates the cricopharyngeus muscle and controls the muscles involved in the esophageal stage of swallowing, as well as those that control respiration. It is the only cranial nerve that influences the structures inferior to the neck. The vagus carries sensory information from the velum and posterior and inferior portions of the pharynx. The vagus also mediates sensation in the larynx. Damage to vagal nerve fibers resulting in decreased motor conduction velocity can cause serious contractility problems with the esophagus, including esophageal dysmotility and megaesophagus. As the vagus nerve is sensory to the esophagus and innervates the lower esophageal sphincter, CVG can also be the etiology of gastroesophageal reflux and the chronic cough that often occurs with it.
In this video, Ross Hauser, MD explains the functional dynamics and possible solutions to speech and swallowing difficulties.
Video Summary Transcript
Cranial Nerve X or the Vagus Nerve plays a vital role in the pharyngeal phase of swallowing. This is what happens during this phase:
- The vocal cords close the larynx to help keep food and liquids from entering the airway and lungs. As the larynx closes, the epiglottis (the skin flap that helps prevent choking) moves to cover it.
Patients with swallowing difficulties caused by a disruption in the pharyngeal phase may suffer from:
- Coughing during swallowing
- Breathing difficulties during swallowing
- A choking sensation
- A change in voice during swallowing
- More severe cases may include food particles passing into the lungs and causing pneumonia-like symptoms or pneumonia itself.
When somebody does have cervical instability it’s normally because of excessive stretching of the ligaments in the back of the neck. When these ligaments are weak, injured, or torn what happens is the cervical vertebrae move forward when they move forward they can impair the nerve’s impulse through these various nerves. More symptoms such as choking on excretions, spit, or mucus can occur. Difficulty in talking may occur if your muscles are too weak to talk.
What are we seeing in this image?
A Digital Motion X-Ray or DMX is a tool we use to help understand a patient’s neck instability and how we may be able to help the patients with our treatments. In the illustration below a patient who suffered from upper cervical instability demonstrated hypermobility of the C1-C2.
Repairing the ligaments and curve for a long-term fix
The goal of our treatment is to repair and strengthen the cervical ligaments and get your head back in alignment with the shoulders in a normal posture. Please see our article on treatments for Atlas displacement c1 forward misalignment.
In our office, we use injection techniques like Prolotherapy to help stabilize the cervical spine. In many patients, we can reverse these symptoms by stabilizing the cervical spine and restoring the neck’s natural curve.
The importance of the vagus nerve as related to overall health cannot be overstated. In cases of cervical ligamentous instability, the vagus nerves and their proper functioning may become disrupted, leading to cervicovagopathy. In severe cases, sympathetic dominance and dysautonomia, as well as widespread illness, may develop. Structural deficiencies in the neck should be addressed with treatments aimed at restoring the structural alignment and integrity of the cervical spine. It is only with these structural treatments that we may be able to reverse many of the chronic diseases that plague humanity.
What are we seeing in this image?
In this illustration, we see the before and after of neck curve corrections. Ligament laxity or looseness or damage, whether the cause is from trauma or genetic as in cases of Ehlers-Danlos syndrome, ultimately causes a kyphotic force on the cervical spine, stretching the posterior ligament complex of the neck. As can be seen in the x-rays of this image, patients with a whiplash injury, Joint Hypermobility Syndrome, and Ehlers-Danlos syndrome can have their cervical curve restored with Prolotherapy Injections and the use of head and chest weights.
Prolotherapy is referred to as a regenerative injection technique (RIT) because it is based on the premise that the regenerative healing process can rebuild and repair damaged soft tissue structures. It is a simple injection treatment that addresses very complex issues.
This video jumps to 1:05 where the actual treatment begins.
This patient is having C1-C2 areas treated. Ross Hauser, MD, is giving the injections.
Treating cervical ligaments with Prolotherapy – published research from Caring Medical
Prolotherapy is an injection technique that stimulates the repair of unstable, torn, or damaged ligaments. When the cervical ligaments are unstable, they allow for excessive movement of the vertebrae, which can stress tendons, atrophy muscles, pinch on nerves, such as the vagus nerve, and cause other symptoms associated with cervical instability including problems of digestion among others.
We hope you found this article informative and that it helped answer many of the questions you may have surrounding Cervical disc disease and swallowing and speech difficulties. Just like you, we want to make sure you are a good fit for our clinic prior to accepting your case. While our mission is to help as many people with chronic pain as we can, sadly, we cannot accept all cases. We have a multi-step process so our team can really get to know you and your case to ensure that it sounds like you are a good fit for the unique testing and treatments that we offer here.
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This article was updated, June 25, 2023