What is Vocal Cord Dysfunction?

Patient Presentation
A 6-year-old male came to clinic for left ear pain during a respiratory illness, that had occurred for 2 days. The evening prior he had a fever to 101.2°F. The past medical history was positive for vocal cord dysfunction diagnosed after stridor, coughing and voice changes that would not improve after a previous viral illness.

The pertinent physical exam showed a current temperature of 100.8°F, respiratory rate of 26 and pulse of 96. He looked tired. HEENT showed erythematous bulging left tympanic membrane with distorted landmarks and dull right tympanic membrane. He had copious rhinorrhea and his throat was normal. Lungs were normal as was the rest of his examination.

The diagnosis of left otitis media was made. The patient was started on antibiotics. The medical student asked the attending physician to explain why the patient was seeing the speech therapist for the vocal cord dysfunction.

Discussion
Vocal cord function involves balancing muscular and neuronal functions. The superior laryngeal nerves (SLN) and recurrent laryngeal nerves (RLN) are the main nerves responsible for sensation and motor innervation. There are two sides to the larynx and they operate ipsilaterally, therefore one side can be affected while the other is not.

Vocal cord paresis or paralysis are “an impairment of the vocal fold motor function that is caused by nerve or neuromuscular abnormalit[ies].” Paresis involves some maintenance of vocal cord movement while paralysis does not. Paresis is also more of a continuum than an absolute movement or not. “Paresis is often considered idiopathic, but potentially any pathology present from skull base to mediastinum that compresses, tethers, stretches, or infiltrates contributing fibers to the SLN or RLN may cause abnormalities.” Common examples in children would be post-viral infections, Lyme disease, neoplasms, and cardiovascular defects and cardiovascular surgery, but many others causes occur. Paralysis is often caused by necessary surgical interventions such as patent ductus arteriosus surgery causing trauma to the RLN as it is a long nerve and traverses multiple body spaces.

Symptoms can include cough, choking, globus sensation, voice changes, dyspnea and feeding difficulties among others. The diagnostic standard is direct visualization while awake when the patient may be able to assist in producing various sounds or types of breathing. Treatment involves speech therapy but the smaller the vocal cord movement the more likely other interventions will be needed including various surgical procedures.

Learning Point
Vocal cord dysfunction (VCD) is a functional disorder and “… is the abnormal closing (adduction) of vocal cords during inspiration and/or expiration.” Patients or parents complain of dyspnea, air hunger, chest or air tightness, dysphonia, hoarseness and globus sensation. Patients (50%) with difficult to control asthma may also have concomitant asthma. Signs include stridor or expiratory stertor, but it may be difficult to trigger during physical examination.

Spirometry may show abnormal flow-loop curves during inspiration or during inspiration and expiration depending on when the abnormality occurs. Flow-loops may be normal between episodes and not show up during the examination. VCD can be exercise-induced (most common) or spontaneous. Exercise-induced is often easier to identify as it occurs more consistently with exercise, whereas spontaneous occurs intermittently and seemingly with or without disparate provokers.

Treatment is speech therapy to teach patients voluntary control of the vocal cords. This is helpful but can be a problem during exercise. Pre-exercise treatment with anticholinergic inhalers (such as Ipratropium) can be used as one option. Long-term data shows a high rate of spontaneous resolution of VCD.

Questions for Further Discussion
1. What causes coughing? A review can be found here
2. How do airway malacias present? A review can be found here
3. What is the difference between stertor and stridor? A review can be found here

Related Cases

To Learn More
To view pediatric review articles on this topic from the past year check PubMed.

Evidence-based medicine information on this topic can be found at SearchingPediatrics.com and the Cochrane Database of Systematic Reviews.

Information prescriptions for patients can be found at MedlinePlus for this topic: Voice Disorders

To view current news articles on this topic check Google News.

To view images related to this topic check Google Images.

To view videos related to this topic check YouTube Videos.

Ivey CM. Vocal Fold Paresis. Otolaryngol Clin N Am. 2019:637-648. Accessed December 21, 2021.

Graham ME, Smith ME. Unilateral Vocal Fold Immobility in Children. Otolaryngologic Clinics of North America. 2019;52(4):681-692. doi:10.1016/j.otc.2019.03.012

Kaplan A, Szefler SJ, Halpin DMG. Impact of comorbid conditions on asthmatic adults and children. NPJ Prim Care Respir Med. 2020;30:36. doi:10.1038/s41533-020-00194-9

Hurvitz M, Weinberger M. Functional Respiratory Disorders in Children. Pediatric Clinics of North America. 2021;68(1):223-237. doi:10.1016/j.pcl.2020.09.013

Author
Donna M. D’Alessandro, MD
Professor of Pediatrics, University of Iowa