Materiały źródłowe

• #1 Bilateral Vocal Cord Paralysis – StatPearls – NCBI Bookshelf

  https://www.ncbi.nlm.nih.gov/books/NBK560852/

  Vocal cord paralysis refers to the immobility of a vocal cord, which can be due to pathology of the vocal ford (also known as the vocal fold) itself, or of the verve that supplies the muscles creating vocal cord motion. […] Vocal cord paralysis refers to the immobility of the vocal cord, while vocal cord paresis refers to the impaired mobility of the vocal cord. Both can be due to processes intrinsically affecting the vocal cord itself (scarring, tumor, etc.), due to cranial neuropathies of the nerves providing vocal cord mobility [the vagus nerve, the recurrent laryngeal nerve (RLN), and the superior laryngeal nerve (SLN)], central neurologic problems [stroke, tumor, multiple sclerosis (MS), etc.], or systemic disease [amyotrophic lateral sclerosis (ALS), Guillain-Barre syndrome, etc.].

• #1 Bilateral Vocal Cord Paralysis – StatPearls – NCBI Bookshelf

  https://www.ncbi.nlm.nih.gov/books/NBK560852/

  The pathophysiology of the intrinsic vocal cord or arytenoid scarring and damage is relatively straightforward: it is a replacement of normally mobile tissues with fibrosis and scar that creates a mechanical tethering of these mobile tissues, preventing normal movement. […] As RLN damage is the most common cause of bilateral vocal cord paralysis, we will review this pathophysiology in more detail. Vagal motor efferent fibers originate in the medulla oblongata. The nucleus ambiguous contains cell bodies of nerves that innervate the soft palate, pharynx, and larynx, while the dorsal nucleus contains visceral efferent fibers to the abdomen and thorax. […] Injury to the RLN is most common, classically leaving the vocal cords in a paramedian position when unilateral or in a median position when bilateral. Injury to the SLN will lower the pitch of the voice and can lead to a bowing deformity of the vocal cords due to a loss of tensile tone from the denervated cricothyroid muscles. […] Bilateral vocal cord paralysis can be caused by injury to the vagus nerve from its cerebral origins to its branches in the thorax and abdomen, and due to some redundancy, the position of the vocal cords (especially in bilateral paralysis) does not always reliably predict the site of the lesion.

• #1 Vocal Cord Paralysis – Ear, Nose, and Throat Disorders – Merck Manual Professional Edition

  https://www.merckmanuals.com/professional/ear-nose-and-throat-disorders/laryngeal-disorders/vocal-cord-paralysis

  Vocal cord paralysis may result from lesions or dysfunction at the level of the nucleus ambiguus, its supranuclear tracts, the main trunk of the vagus, or the recurrent laryngeal nerves. The left vocal cord is paralyzed more often than the right because the left recurrent nerve takes a longer course from the brain stem to the larynx, providing more opportunity for compression, traction, or surgical injuries. […] Most paralyses are unilateral and affect mainly the voice, but bilateral paralysis can occur and obstruct the airway. […] Various surgical procedures are available to improve voice quality in unilateral paralysis or to improve airway patency in long-term bilateral paralysis.

• #1 Vocal Cord Paralysis: Pathophysiology, Etiologies, and Evaluation

  https://www.ijhns.com/abstractArticleContentBrowse/IJHNS/27529/JPJ/fullText

  Vocal fold paralysis often leads to significant morbidity including dysphonia, dysphagia and aspiration. […] An appropriate understanding of the pathophysiology, etiologies, and a systematic method of evaluation are essential for discussing prognosis and offering patients appropriate treatments. […] Damage or injury to these nerves may result in vocal fold paresis or paralysis. […] Vocal fold paralysis implies complete vocal fold immobility due to neurological injury. […] It is important to differentiate between nerve conduction block and presence of axonal injury for prognostication purposes when possible. […] Most surgically induced nerve injuries are the result of pressure, crushing or heating intraoperatively, leaving the nerve macroscopically intact. […] Neuropraxia is the mildest form of injury, in which the Schwann cells are injured but the axon integrity is maintained, often resulting in a conduction block lasting for 6-8 weeks whilst the Schwann cells repair.

• #1 Vocal Cord Paralysis | IntechOpen

  https://www.intechopen.com/chapters/81705

  Vocal cord paralysis can be due to neurogenic cause, trauma due to surgery, or mechanical fixation of the cords. […] Most commonly, there is paralysis of recurrent laryngeal nerve. […] Vocal cord refers to the immobility of vocal cord. It can be unilateral or bilateral. Both can be due to diseases affecting the vocal cord itself such as tumor or scarring; or due to paralysis of recurrent laryngeal nerve or superior laryngeal nerve. […] Vocal cord paralysis is most commonly unilateral. The affected vocal cords do not adduct or abduct properly causing voice disorder. […] RLN damage is the most common cause of vocal cord paralysis. Combined paralysis of RLN and SLN is also possible and is seen post-thyroidectomy surgeries due to iatrogenic trauma. […] To understand the pathophysiology of vocal cord paralysis, it is of importance to know the origin and course of vagus nerve and its branches as they give rise to laryngeal sensory and motor supply.

• #1 Vocal Cord Paralysis | IntechOpen

  https://www.intechopen.com/chapters/81705

  Vagus nerve has two nucleinucleus ambiguous and dorsal nucleus of vagus. […] The superior laryngeal nerve arises from inferior ganglion of vagus and descends behind internal carotid artery, and at the level of greater cornua of hyoid, it divides into internal and external branches. […] On the right side, RLN arises from vagus in front of subclavian artery in lower part of neck, and it traversus below the subclavian artery after emerging from vagus nerve. […] The left RLN has longer course and from its origin at the anterior surface of arch of aorta to the interspace between origin of left common carotid artery and subclavian artery. […] There are two theories to explain the position of vocal cord in cases of cord paralysis. Semons law states that in the sequence of position of the vocal cords in slowly progressive organic central lesions, motor nerve fibers supplying the abductors of vocal cords become involved much earlier than adductors.

• #1 Vocal Cord Paralysis: Pathophysiology, Etiologies, and Evaluation

  https://www.ijhns.com/abstractArticleContentBrowse/IJHNS/27529/JPJ/fullText

  Axonotmesis is when axonal injury is present, leading to possible neuron death or reinnervation with variable functional outcomes. […] Acute unilateral paralysis of one RLN will cause denervation and loss of function to the TA, LCA, PCA, and IA muscles, with the IA being less affected due to additional nervous supply. […] The summation of these effects, seen in acute complete paralysis of one RLN, is the loss of vocal fold mass, abduction, and adduction resulting in glottic incompetence. […] The motor axons of the RLN contain four times as many adductor axons as there are abductor axons, and when nerve injury is followed by regeneration, these axons maintain their adductor and abductor affinity, however may regenerate inappropriately with distal axons of the opposite type. […] Laryngeal synkinesis is a form of defective healing where severed nerve sheaths do not accurately regenerate to their preinjury counterpart, causing uncoordinated muscle contraction.

• #1 Pathophysiology of Recurrent Laryngeal Nerve Injury | Ento Key

  https://entokey.com/pathophysiology-of-recurrent-laryngeal-nerve-injury/

  The risk of synkinesis increases with the degree of nerve injury. […] The prognosis for recovery of motor function is better when the nerve lesion is more distal, closer to the target muscle. […] The strong propensity for regeneration of the recurrent laryngeal nerve is well documented in the literature.

• #1 Vocal cord paralysis: anatomy, imaging and pathology

  https://pmc.ncbi.nlm.nih.gov/articles/PMC4263806/

  Around 40 % of unilateral VCP and 50 % of bilateral VCP is caused by surgical injury. […] Unilateral VCP was idiopathic in almost 20 % of cases. […] Malignancy outside the larynx was the third most common cause of unilateral VCP, being responsible for 14 % of cases. […] Traumatic injury causes about 6 % of all unilateral VCPs and is most frequently intubation related. […] VCP can be caused by any offending lesion in the course of the vagal and recurrent laryngeal nerves, between the medulla oblongata and the aortic arch.

• #1 Vocal cord paralysis – Symptoms and causes – Mayo Clinic

  https://www.mayoclinic.org/diseases-conditions/vocal-cord-paralysis/symptoms-causes/syc-20378873

  Vocal cord paralysis is a condition that causes the loss of control of the muscles that control the voice. It happens when the nerve impulses to the voice box, also called the larynx, are disrupted. This results in paralysis of the vocal cord muscles. […] Vocal cord paralysis happens when nerve impulses to the voice box, known as the larynx, are disrupted. This causes the muscle to become paralyzed. Often the exact cause of vocal cord paralysis isn’t known. But some known causes may include: […] Injury to the vocal cord during surgery. Surgery on or near the neck or upper chest can result in damage to the nerves that serve the voice box. Surgeries that carry a risk of damage include surgeries to the thyroid or parathyroid glands, esophagus, neck, and chest. […] Neck or chest injury. Trauma to the neck or chest may injure the nerves that serve the vocal cords or the voice box itself.

• #1 Vocal Cord Paralysis: Pathophysiology, Etiologies, and Evaluation

  https://www.ijhns.com/abstractArticleContentBrowse/IJHNS/27529/JPJ/fullText

  Recurrent laryngeal nerve injury from anterior approaches to the cervical spine is the most common complication of these procedures, quoted at 2-6%. […] Damage to the RLN following thyroid surgery is a well-known complication, having been recognized for over a century and being a common cause for litigation. […] The most common nonlaryngeal neoplasms causing RLN paralysis are thyroid, lung, oesophageal and mediastinal. […] The exact mechanism of endotracheal intubation-induced RLN paralysis remains unknown. […] Several viruses have been cited as causing RLN paralysis, however proving viral etiology remains difficult, as positive biochemical testing does not prove neural involvement nor causation. […] The clinician must always bear in mind unusual causes for vocal cord paralysis should the more common causes prove to be not responsible. […] Idiopathic etiologies have no cause by definition. […] Laryngeal electromyography (LEMG) is considered the gold standard investigation to diagnose and evaluate the type and degree of neurological injury in vocal cord paralysis.

• #1 Vocal Cord Paralysis / Insufficiency Treatments – Medical Clinical Policy Bulletins | Aetna

  https://www.aetna.com/cpb/medical/data/200_299/0253.html

  Most cases of peripheral vocal cord paralysis are secondary to thyroidectomy or non-laryngeal neoplasms, including bronchogenic, esophageal, and thyroid carcinoma. […] Other less common lesions causing paralysis of the vocal cord include tumors of the deep lobe of the parotid gland, carotid body tumors, glomus jugulare and vagale tumors, and neurogenic neoplasms of the tenth nerve and jugular foramen. […] External penetrating wounds to the neck or prolonged endotracheal intubation may also traumatize the recurrent laryngeal nerve, producing vocal cord paralysis. […] Finally, toxic neuropathy and idiopathic causes account for a few cases. […] In adults, unilateral recurrent laryngeal nerve paralysis generally produces hoarseness and a weak, breathy voice with varying amounts of aspiration.

• #1

  https://journals.lww.com/jolv/fulltext/2017/07020/postintubation_recurrent_laryngeal_nerve_palsy__a.1.aspx

  The mechanism of recurrent laryngeal nerve paralysis due to tracheal intubation is usually an indirect injury. […] The factors of indirect injury are said to include tracheal tube size, location of the cuff, fixing side of the tube, cuff pressure, curvature of tracheal tube, and intubation time. […] This compression of the recurrent nerve and its peripheral branches in the larynx causes degeneration and subsequent nerve paralysis. […] Insufficient microcirculatory supply to the nerve and its branches may cause ischemic neuronal degeneration and subsequent paralysis. […] An inflated cuff may compress the anterior branch of the recurrent laryngeal nerve, therefore, the cuff should be located at more than 15 mm below the vocal cords. […] Other types of endotracheal tubes are also known to cause vocal cord paralysis.

• #1

  https://journals.lww.com/jolv/fulltext/2017/07020/postintubation_recurrent_laryngeal_nerve_palsy__a.1.aspx

  Overextension of the neck causing stretching of both vagus nerves is also believed to be another mechanism for vocal cord paralysis. […] Damage to the left recurrent laryngeal nerve can also occur during insertion of a nasogastric tube through the esophagus. […] Kikura et al. have found a clear relationship between aging and an increased risk of vocal cord paralysis. […] The proposed mechanism is that diabetics have associated peripheral neuropathy which may increase susceptibility to paralysis. […] Recurrent laryngeal nerve injury due to endotracheal intubation is a known, but often overlooked cause for vocal cord dysfunction in the operating room and the ICU. […] Recurrent laryngeal nerve palsy due to endotracheal tube pressure is usually temporary and once the condition is recognized and understood, need not be cause for undue alarm.

• #1 Vocal cord paralysis – Symptoms and causes – Mayo Clinic

  https://www.mayoclinic.org/diseases-conditions/vocal-cord-paralysis/symptoms-causes/syc-20378873

  Stroke. A stroke interrupts blood flow in the brain and may damage the part of the brain that sends messages to the voice box. […] Tumors. Tumors, both cancerous and noncancerous, can grow in or around the muscles, cartilage or nerves controlling the function of the voice box. This can cause vocal cord paralysis. […] Infections. Some infections, such as Lyme disease, Epstein-Barr virus and herpes, can cause inflammation and directly damage the nerves in the voice box. There’s some evidence that infection with COVID-19 may cause vocal cord paralysis. […] Neurological conditions. Certain neurological conditions, such as multiple sclerosis or Parkinson’s disease, can lead to vocal cord paralysis.

• #1 Vocal Cord Paralysis Treatment NYC | Mount Sinai – New York

  https://www.mountsinai.org/locations/grabscheid-voice-swallowing-center/conditions/vocal-cord-paralysis

  Vocal cord paralysis occurs when the nerve impulses to your voice box (larynx) are interrupted. This results in paralysis of your vocal cord muscle. Vocal cord paralysis can affect your ability to speak and even breathe. […] In vocal cord paralysis, the nerve impulses to your voice box (larynx) are interrupted, resulting in paralysis of the muscle. Doctors often don’t know the cause of vocal cord paralysis. Known causes include: […] Inflammation. Arthritis or surgery can cause inflammation and scarring of the vocal cord joints or the space between the two vocal cord cartilages. This inflammation may prevent your vocal cords from opening and closing. The signs and symptoms of this disorder mimic vocal cord paralysis, even though the vocal cord nerves remain normal. In addition, some viral infections can inflame and damage the nerves in the larynx. […] If you have certain neurological conditions, such as multiple sclerosis or Parkinson’s disease, you may experience vocal cord paralysis. However, these conditions are more likely to cause vocal cord weakness than complete paralysis.

• #1 Vocal Fold Motion Impairment in Neurodegenerative Diseases

  https://www.mdpi.com/2077-0383/13/9/2507

  Vocal fold motion impairment (VFMI) is the inappropriate movement of the vocal folds during respiration, leading to vocal fold adduction and/or abduction problems and causing respiratory and vocal impairments. […] VFMI in NDDs is caused by the following: laryngeal muscle weakness due to muscular atrophy, caused by brainstem and motor neuron degeneration in amyotrophic lateral sclerosis; hyperactivity of laryngeal adductors in Parkinson’s disease; and varying degrees of laryngeal adductor hypertonia and abductor paralysis in multiple system atrophy. […] The exact pathophysiology of vocal fold dysmotility in ALS is not fully understood; however, it is thought to have multiple causes involving both infranuclear and supranuclear origins, resulting in the degeneration of the motor neurons that control the muscles of the larynx.

• #1 Vocal Cord Paralysis: Causes, Symptoms & Treatment

  https://my.clevelandclinic.org/health/diseases/17624-vocal-cord-paralysis

  Poisonous substances: Toxins, including lead, mercury and arsenic, can harm nerve tissue. […] Surgery: Surgeries in your head and neck, including thyroid gland removal (thyroidectomy), parathyroid surgery, heart surgery and cervical spine surgery, can lead to complications, like nerve injury. […] Tumors: Cancerous (malignant) tumors and noncancerous (benign) tumors can push on the nerves in your voice box, causing damage. […] Sometimes, a vocal cord can get paralyzed after a cold or upper respiratory infection. […] Treatment depends on the severity of the paralysis and your symptoms. […] If paralysis is mild, you may need voice therapy to improve how your vocal cords work. […] More severe vocal cord paralysis may require surgery. […] With unilateral vocal cord paralysis, providers often choose to delay surgery for up to a year to allow time for the condition to improve.

• #1 Vocal cord paralysis – Airway Unit, Service of Otorhino-laryngology – CHUV

  https://www.chuv.ch/en/voies-aeriennes/orva-home/patients-and-families/glossary/vocal-cord-paralysis

  Immediately after birth, vocal cord paralysis may be secondary to compression of the brainstem, as in Arnold-Chiari malformation, meningoencephalocele or conditions with raised intracranial tension. […] In the newborn, the vocal cords may be paralyzed with no etiology identified (idiopathic palsy). […] There could be history of traumatic birth. […] An MRI and CT scan is done to evaluate and exclude brain, neck and mediastinal causes.

• #1 Vocal cord paralysis | PPT

  https://www.slideshare.net/slideshow/vocal-cord-paralysis/26355965

  Vocal cord paralysis is defined as total interruption of nerve impulses resulting in no movement of laryngeal muscles, while paresis is partial interruption causing weak movement. […] Causes of laryngeal paralysis can be supranuclear, nuclear, related to high or low vagal lesions, or systemic. […] In unilateral recurrent laryngeal nerve paralysis, the vocal cord assumes a median position and does not move laterally on inspiration. […] Bilateral paralysis causes stridor and dyspnea due to […] The vocal cords thus assumes a median or paramedian position doesn’t move laterally on deep inspiration. […] Unilateral injury to recurrent laryngeal nerve results in ipsilateral paralysis of all the intrinsic muscles of larynx except the cricothyroid. […] The voice in unilateral paralysis gradually improves due to compensation by healthy cord which crosses midline to meet paralysed one. […] Bilateral paralysis from neuritis causes both cords to be in the paramedian position, resulting in breathing difficulties that worsen with exertion. […] Treatment may include cord lateralization procedures like arytenoidectomy or thyroplasty to improve breathing.

• #1 RESOLUTION OF VOCAL CORD PARALYSIS BY TREATING A RECURRENT LARYNGEAL NERVE ENTRAPMENT | Published in Journal of Contemporary Chiropractic

  https://journal.parker.edu/article/78071

  The acute effects are immediate flaccidity of the ipsilateral vocal fold, loss of abduction and adduction, severe dysphonia to complete paralytic aphonia, and, frequently, aspiration of food and drink into the trachea. […] Following acute denervation, the subsequent progression is either chronic denervation or nerve regeneration with laryngeal muscle reinnervation. […] The authors preference is nerve transfer, insofar as the quality of resultant phonatory voice, in his hands, has been superior to the other techniques. […] The current mechanisms for immobile vocal cord after intubation are either due to mechanical injury by dislocation or subluxation of arytenoid joints or direct nerve injury. The anterior ramus of the recurrent laryngeal nerve is vulnerable to compression between the thyroid cartilage and endotracheal tube cuff about 6-10mm below the cords. The increase in cuff pressure compresses the vasa nervosus, leading to ischemic injury of this branch.

• #1 Vocal Cord Paralysis | IntechOpen

  https://www.intechopen.com/chapters/81705

  Wegner and Grossman hypothesis explains the median and paramedian position of cords after RLN palsy, on the basis that cricothyroid muscle that receives supply from superior laryngeal nerve takes over it has adductor and tensor function. […] RLN damage is the most common cause of bilateral vocal cord paralysis. Combined paralysis of RLN and SLN is also possible and is seen post-thyroidectomy surgeries due to iatrogenic trauma. […] Bilateral vocal cord paralysis can be caused by injury to the vagus nerve near its origin or anywhere along its course or injury to its branches RLN and SLN through neck, thorax, and abdomen. […] Injury to the RLN is most common, classically leaving the vocal cords in a median position in case of bilateral vocal cord paralysis. […] Injury to the SLN will lower the pitch of the voice and can lead to a bowing deformity of the vocal cords due to a loss of tone from the dennervated cricothyroid muscles. […] A high vagal injury can leave the cord in a nearly fully abducted position.

• #1 Vocal Cord Paralysis-Pathophysiology | PDF

  https://www.scribd.com/document/16949871/Vocal-Cord-Paralysis-pathophysiology

  Vocal cord paralysis can be caused by injuries, tumors, infections, or neurological conditions that damage the recurrent laryngeal nerve. This results in unilateral or bilateral vocal cord paralysis. […] Bilateral paralysis significantly impairs phonation and respiration by obstructing breathing on inspiration and producing stridor. […] Unilateral or bilateral vocal cord paralysis. When bilateral: significant functional impairment of phonation and respiration. […] Breathing is obstructed on inspiration, producing a condition known as stridor. […] Signs: hoarseness or complete voice loss; absent, abnormal, or nearly normal voice; breathy, weak, low-pitched, or high-pitched dysphonia; short vocalizations and coughing or choking when eating or drinking which may lead to aspiration or pneumonia; dysphagia which could result to aspiration of liquids.

• #1 Vocal Cord Dysfunction | AAFP

  https://www.aafp.org/pubs/afp/issues/2010/0115/p156.html

  Vocal cord dysfunction involves inappropriate vocal cord motion that produces partial airway obstruction. […] The differential diagnosis includes asthma, angioedema, vocal cord tumors, and vocal cord paralysis. […] Vocal cord dysfunction is associated with a variety of precipitating factors, but no clear unifying pathophysiology has been identified. […] Gastroesophageal reflux disease (GERD) has been implicated in triggering vocal cord dysfunction. […] Neuroleptic drugs, specifically phenothiazines, may cause transient vocal cord dysfunction. […] The most valuable diagnostic tests for vocal cord dysfunction are pulmonary function testing with a flow-volume loop and flexible laryngoscopy. […] Flexible laryngoscopy is considered the diagnostic standard for vocal cord dysfunction. Direct observation of abnormal vocal cord movement toward the midline during inspiration or expiration confirms the diagnosis. […] Management of chronic vocal cord dysfunction begins with treatment or elimination of precipitating factors, including GERD, rhinosinusitis, psychological conditions, airborne irritants, and certain medications.

• #1 Vocal Cord Paralysis | Henry Ford Health – Detroit, MI

  https://www.henryford.com/services/voice/vocal-cord/treatments/paralysis

  Vocal cord paralysis is a voice disorder that occurs when one or both of the vocal cords (or vocal folds) do not open or close properly. […] The most common causes of vocal cord paralysis are surgical traumas to the neck and chest. Other causes include head trauma, stroke, neurological conditions such as multiple sclerosis or Parkinsons disease, neck injury, lung or thyroid cancer, a tumor pressing on a nerve or a viral infection. […] Laryngeal electromyography (EMG) is a test that involves inserting a needle into the muscles of the larynx to detect the neuromuscular function of the vocal folds. This test, which is done by an otolaryngologist together with a neurologist, can help determine the likelihood that a paralyzed vocal fold will recover or not. […] Surgical treatment for one paralyzed vocal cord focuses on improving the vocal cords ability to close. […] When both cords are affected, the problem is less often voice and more that there is not enough room between the vocal cords for breathing. Surgical treatment is aimed at opening the airway by removing a portion of the vocal cord and/or arytenoid cartilage.

• #1 Paralysis (Bilateral) | Sean Parker Institute for the Voice

  https://voice.weill.cornell.edu/voice-disorders/paralysis-bilateral

  Bilateral paralysis is more likely than unilateral paralysis to be related to stroke or other neurological disease, so a brain scan may be useful as well. […] Initial (and sometimes, emergency) treatment of bilateral paralysis is aimed at making sure the airway will not be blocked. This requires a tracheostomy, which is the creation of a surgical opening from the skin to the trachea. Subsequently, some cases of paralysis recover by themselves. […] Some physicians have found electromyography (EMG) to be useful, both to diagnose paralysis and to help determine how likely it is that it will recover on its own. EMG is performed by placing needles into the muscles of the larynx though the skin of the neck for a few minutes to record electrical activity. […] If the vocal folds do not recover motion, it is possible to continue indefinitely with a tracheostomy to ensure the airway is open. Removing the tracheostomy, however, requires that the airway be widened, most commonly by surgically removing a part of the vocal fold. This is an irreversible procedure, which may worsen voice and swallowing, and so should be considered carefully.

• #1 Vocal cord paralysis | PPT

  https://www.slideshare.net/slideshow/vocal-cord-paralysis-67196533/67196533

  Laryngeal paralysis can be: Unilateral or Bilateral may involve 1. Recurrent laryngeal nerve 2. Superior laryngeal nerve 3. Both (Combined / Complete). […] Causes of laryngeal paralysis can be supranuclear, nuclear, related to high or low vagal lesions, or systemic. […] Thyroidectomy is commonest cause of bilateral laryngeal paralysis. […] Imaging should include the entire path of the vagus/recurrent laryngeal nerve involved. […] LEMG findings can be diagnostic and prognostic and can therefore be a useful tool to guide therapy. […] It states that complete paralysis of the recurrent laryngeal nerve results in the vocal cord being in paramedian because of an intact cricothyroid muscle, which adducts the vocal cord. […] Unilateral injury to recurrent laryngeal nerve results in ipsilateral paralysis of all the intrinsic muscles of larynx except the cricothyroid.

• #1 Revisiting CT Signs of Unilateral Vocal Fold Paralysis: A Single, Blinded Study | American Journal of Neuroradiology

  http://www.ajnr.org/content/43/4/592

  Several CT findings are thought to be indicative of vocal cord paralysis; however, these signs have never been validated in a blinded fashion. […] This disease process develops as a result of injury to the vagus nerve or recurrent laryngeal nerve, a branch of the vagus nerve. Up to 40% of cases are idiopathic. […] In the absence of a history of a neck or cervical spinal operation, laryngeal trauma, or known malignancy, the standard diagnostic work-up includes CT from the skull base through the mediastinum to assess a lesion along the course of the nerve. […] Although cord palsy is often diagnosed clinically, up to 30% of cases may be asymptomatic and clinically unsuspected. […] There are many imaging signs to suggest vocal cord paralysis with varying degrees of sensitivity and specificity.

• #1 Unilateral Laryngeal Paralysis or Vocal Cord Paralysis | Iowa Head and Neck Protocols

  https://medicine.uiowa.edu/iowaprotocols/unilateral-laryngeal-paralysis-or-vocal-cord-paralysis

  Vocal cord paralysis appears to be caused by compression of the left recurrent laryngeal nerve between the enlarged hypertensive pulmonary artery, the aorta, and the ligamentum arteriosum and not by dilatation of the left atrium, as some observers have thought. […] Vocal Cord Paralysis – lack of neurologic input to the larynx (intracranial, vagal, RLN). […] Arytenoid Fixation. […] Three-dimensional CT imaging has been touted as useful in discriminating between paralysis and subluxation/dislocation.

• #1 Revisiting CT Signs of Unilateral Vocal Fold Paralysis: A Single, Blinded Study | American Journal of Neuroradiology

  http://www.ajnr.org/content/43/4/592

  The presence of medial displacement of the posterior ipsilateral vocal fold margin and ipsilateral laryngeal ventricular dilation yielded the greatest positive predictive value. […] Overall, sensitivity and negative predictive values were low. […] Predicting vocal cord paralysis on the basis of CT findings is not as accurate or straightforward in prospectively predicting vocal cord paralysis as implied in prior studies. […] The sensitivity and specificity of the imaging criteria were evaluated on the basis of consensus of radiologists. […] It is not as accurate or straightforward to prospectively predict vocal cord paralysis based on CT findings as previously implied in prior studies.

• #1 Pathophysiology of Recurrent Laryngeal Nerve Injury | Ento Key

  https://entokey.com/pathophysiology-of-recurrent-laryngeal-nerve-injury/

  Laryngeal nerve injury is a severe and frequently encountered complication of thyroid surgery, and it is a source of considerable morbidity. […] This chapter deals with the pathophysiology of recurrent laryngeal nerve (RLN) paralysis. […] The severity of symptoms is influenced by the degree of the insult, regeneration of the nerve, and compensatory functional reserve of the larynx. […] Just as in unilateral nerve injuries, there is a range of residual and regenerated activity of laryngeal muscles in patients with bilateral RLN injury. […] The preponderance of experimental evidence does not support the notion that the cricothyroid muscle adducts the vocal fold. […] Peripheral nerves, including the RLN, have a strong propensity for regeneration and reinnervation of muscles. However, functional recovery is usually poor.

• #1 Common Questions about Vocal Fold Paralysis – Department of Surgery

  https://www.surgery.wisc.edu/2019/04/19/common-questions-about-vocal-fold-paralysis/

  Unilateral vocal fold paralysis often improves spontaneously over the first 6-12 months after the injury. […] Classically, vocal fold paralysis results in glottal incompetence reduced laryngeal valving ability due to an impaired ability of the vocal folds to meet at midline. […] Importantly, vocal fold paralysis has been shown to have a substantial impact on quality-of-life and new tools are being developed to measure this impact. […] As vocal fold paralysis is a neuromuscular disorder, it cannot be reversed by voice therapy.

• #1 Vocal Fold Paralysis Causes, Diagnosis, Symptoms, & Treatment

  https://throatdisorder.com/voice-disorders/vocal-fold-paralysis/

  Vocal fold paralysis is typically due to a problem with the recurrent laryngeal nerve, the nerve that controls motion of the vocal fold. […] When the nerve to the vocal fold is affected, it leaves the vocal cord immobile and paralyzed. […] Swelling of the nerve for unknown reasons. This is also known as idiopathic vocal cord paralysis and occurs is responsible for paralysis approximately 30% of the time. […] The symptoms of vocal fold paralysis occur because the vocal folds are unable to meet in the midline. Sound production is weak and patients feel out of breath because they have a constant air escape from the lungs through the voice box. […] In cases in which vocal fold paralysis is potentially reversible, such as a when idiopathic, or when the nerve is inflamed (but not cut) after surgery, paralysis may resolve up to one year after injury.

• #1 Paralysis (Unilateral) | Sean Parker Institute for the Voice

  https://voice.weill.cornell.edu/voice-disorders/paralysis-unilateral

  Finding a cause for a paralyzed vocal fold can be simple, as in hoarseness that occurs immediately after neck surgery, or very challenging. […] In unilateral paralysis, the vocal folds are unable to close, which causes voice and swallowing problems. […] Vocal fold paralysis is diagnosed by a lack of movement in a vocal fold. […] In recent years, it has become clear that vocal folds may be only partially paralyzed. This is called paresis, and because the vocal fold retains some ability to move, can be especially challenging to diagnose. […] Some cases of vocal fold paralysis recover by themselves. […] Many otolaryngologists recommend waiting six months to a year to allow for vocal fold paralysis to clear up on its own before performing corrective surgery. […] In most cases of unilateral vocal fold paralysis, it is possible to restore near-normal conversation voice, even though, so far, it has not been possible to restore motion to an immobile vocal fold. Treatment is based on repositioning the immobile vocal fold closer to its partner.

• #1 RESOLUTION OF VOCAL CORD PARALYSIS BY TREATING A RECURRENT LARYNGEAL NERVE ENTRAPMENT | Published in Journal of Contemporary Chiropractic

  https://journal.parker.edu/article/78071

  Other mechanisms also need to be considered for potential causes of VCP. Arthroscopic shoulder surgeries are typically done in 1 of 2 positions, either the beach-chair position of the lateral decubitus position. […] Regardless of the exact cause of the drop in blood pressure, it should be noted that the RLN is grouped within the Vagus nerve until it branches off. […] This entrapment could be manifested by the duration and position of the patients head and neck during her surgery, possibly placing tension through the lateral cervical paramusculature. […] The importance of this case suggests plausible treatment to the entrapment site(s) of the RLN to help resolve vocal cord paralysis. More studies are needed to demonstrate effectiveness of treatment.

• #1 Stem cell implants offer hope for vocal cord paralysis – Otolaryngology–Head & Neck Surgery

  https://oto.wustl.edu/stem-cell-implants-offer-hope-for-vocal-cord-paralysis/

  Vocal cord paralysis occurs when nerve impulses to the larynx are disrupted, causing problems with speech and breathing. […] The nerve to the vocal cords can be injured in a variety of ways, including surgical injury (especially thyroid surgery), tumors and viral infections. […] According to Dr. Paniello, adult muscle stem cells (MSCs), implanted into a muscle that has lost its nerve, can improve muscle function, in part by regrowth of the nerve for that muscle. […] The desired outcome is restoration of nerve function, but nerves grow slowly, so it takes several months to know whether or not an intervention has helped. […] Implanting MSCs into the vocal cord closing muscles improves that functional recovery to 128% of baseline. Implanting MSCs into the opening muscles also showed enhanced improvement, up to 83% of normal.

• #1 Vocal Cord Paralysis | Condition | UT Southwestern Medical Center

  https://utswmed.org/conditions-treatments/vocal-cord-paralysis/

  Vocal cord paralysis develops when nerves that control the vocal cord muscles become damaged or inflamed. […] Often, the underlying causes of vocal cord paralysis are not known. Some known causes include: […] We typically recommend surgical procedures for patients whose symptoms dont improve with conservative treatments. Our surgeons offer: […] Laryngeal reinnervation surgery: Procedure to connect a damaged nerve to a functioning nerve to improve nerve signals that control vocal cord muscles.

• #2 Vocal cord paresis – Wikipedia

  https://en.wikipedia.org/wiki/Vocal_cord_paresis

  Vocal fold paresis refers to a partial loss of input to the nerve of the vocal folds. This loss of neural input leads to reduced vocal fold mobility. […] Vocal fold paralysis, distinguished from vocal paresis, is the total loss of vocal fold mobility due to a lack of neural input to the vocal folds. […] These conditions result from continuous damage to the laryngeal nerves and often lead to vocal disability.

• #2 Unilateral Vocal Fold Paralysis: Practice Essentials, History of the Procedure, Problem

  https://emedicine.medscape.com/article/863779-overview

  Unilateral vocal fold paralysis (UVFP) occurs from a dysfunction of the recurrent laryngeal or vagus nerve innervating the larynx. […] The recurrent laryngeal nerve is responsible for both abduction and adduction of the vocal fold. The recurrent laryngeal nerve originates from the vagus nerve, which originates from the brainstem (nucleus ambiguous in the medulla) and travels along the carotid sheath (with the jugular vein and internal carotid artery). The left vagus nerve gives rise to the left recurrent laryngeal nerve as the vagus crosses the arch of the aorta. The left recurrent laryngeal nerve then loops under the ligamentum arteriosum and travels cephalad in the tracheoesophageal groove until it penetrates the larynx to innervate the intrinsic muscles of the larynx. […] Because of the circuitous nature of the recurrent laryngeal nerve, multiple disease processes and operative procedures put these important nerves at risk, often resulting in vocal fold paralysis.

• #2 Bilateral Vocal Cord Paralysis – StatPearls – NCBI Bookshelf

  https://www.ncbi.nlm.nih.gov/books/NBK560852/

  The pathophysiology of the intrinsic vocal cord or arytenoid scarring and damage is relatively straightforward: it is a replacement of normally mobile tissues with fibrosis and scar that creates a mechanical tethering of these mobile tissues, preventing normal movement. […] As RLN damage is the most common cause of bilateral vocal cord paralysis, we will review this pathophysiology in more detail. Vagal motor efferent fibers originate in the medulla oblongata. The nucleus ambiguous contains cell bodies of nerves that innervate the soft palate, pharynx, and larynx, while the dorsal nucleus contains visceral efferent fibers to the abdomen and thorax. […] Injury to the RLN is most common, classically leaving the vocal cords in a paramedian position when unilateral or in a median position when bilateral. Injury to the SLN will lower the pitch of the voice and can lead to a bowing deformity of the vocal cords due to a loss of tensile tone from the denervated cricothyroid muscles. […] Bilateral vocal cord paralysis can be caused by injury to the vagus nerve from its cerebral origins to its branches in the thorax and abdomen, and due to some redundancy, the position of the vocal cords (especially in bilateral paralysis) does not always reliably predict the site of the lesion.

• #2 Vocal Cord Paralysis | IntechOpen

  https://www.intechopen.com/chapters/81705

  Vagus nerve has two nucleinucleus ambiguous and dorsal nucleus of vagus. […] The superior laryngeal nerve arises from inferior ganglion of vagus and descends behind internal carotid artery, and at the level of greater cornua of hyoid, it divides into internal and external branches. […] On the right side, RLN arises from vagus in front of subclavian artery in lower part of neck, and it traversus below the subclavian artery after emerging from vagus nerve. […] The left RLN has longer course and from its origin at the anterior surface of arch of aorta to the interspace between origin of left common carotid artery and subclavian artery. […] There are two theories to explain the position of vocal cord in cases of cord paralysis. Semons law states that in the sequence of position of the vocal cords in slowly progressive organic central lesions, motor nerve fibers supplying the abductors of vocal cords become involved much earlier than adductors.

• #2 Vocal cord paralysis | Radiology Reference Article | Radiopaedia.org

  https://radiopaedia.org/articles/vocal-cord-paralysis?embed_domain=external.radpair.com%252525252527%25252525255b0%25252525255dfavicon.icofavicon.icofavicon.icofavicon.ico&lang=us

  Vocal cord paralysis/paresis (VCP), also known as vocal fold paralysis/paresis, refers to the impaired mobility of the true vocal cord or fold due to neurologic dysfunction. […] Neurologic dysfunction resulting in vocal cord paralysis most common localizes to the recurrent laryngeal nerve, but can also be due to upstream lesions affecting the vagus nerve (from which the recurrent laryngeal nerve branches off) or the brain. Injury to the recurrent laryngeal nerve affects motor function of most of the intrinsic laryngeal muscles (posterior cricoarytenoid, lateral cricoarytenoid, transverse arytenoid, oblique arytenoid, and thyroarytenoid). […] Unilateral involvement is much more common than bilateral involvement. The left side is most commonly affected, likely because the longer course of the left recurrent laryngeal nerve presents greater opportunity for injury.

• #2 Vocal Cord Paralysis: Pathophysiology, Etiologies, and Evaluation

  https://www.ijhns.com/abstractArticleContentBrowse/IJHNS/27529/JPJ/fullText

  Axonotmesis is when axonal injury is present, leading to possible neuron death or reinnervation with variable functional outcomes. […] Acute unilateral paralysis of one RLN will cause denervation and loss of function to the TA, LCA, PCA, and IA muscles, with the IA being less affected due to additional nervous supply. […] The summation of these effects, seen in acute complete paralysis of one RLN, is the loss of vocal fold mass, abduction, and adduction resulting in glottic incompetence. […] The motor axons of the RLN contain four times as many adductor axons as there are abductor axons, and when nerve injury is followed by regeneration, these axons maintain their adductor and abductor affinity, however may regenerate inappropriately with distal axons of the opposite type. […] Laryngeal synkinesis is a form of defective healing where severed nerve sheaths do not accurately regenerate to their preinjury counterpart, causing uncoordinated muscle contraction.

• #2 Vocal cord paralysis: anatomy, imaging and pathology | Insights into Imaging | Full Text

  https://insightsimaging.springeropen.com/articles/10.1007/s13244-014-0364-y

  Around 40 % of unilateral VCP and 50 % of bilateral VCP is caused by surgical injury. […] Unilateral VCP was idiopathic in almost 20 % of cases. […] Malignancy outside the larynx was the third most common cause of unilateral VCP, being responsible for 14 % of cases. […] VCP can be caused by any offending lesion in the course of the vagal and recurrent laryngeal nerves, between the medulla oblongata and the aortic arch.

• #2 Vocal Cord (Fold) Paralysis – ENT Health

  https://www.enthealth.org/conditions/vocal-cord-fold-paralysis/

  Vocal cord paralysis and paresis can result from abnormal function of the nerves that control your voice box muscles (laryngeal muscles). […] Vocal cord paralysis can happen at any age and come from different causes, including: […] Surgery in the neck (thyroid gland, carotid artery, cervical spine) or in the chest (lungs, esophagus, heart, or large blood vessels) may cause RLN or SLN paresis or paralysis. […] Tumors (both cancerous and non-cancerous) can grow around nerves and squeeze them, resulting in varying degrees of paresis or paralysis. […] Inflammation from infections may injure a brain nerve (called the vagus) or its nerve branches to the voice box (RLN and SLN). […] Various auto-immune diseases can cause transient or permanent vocal cord paralysis. […] Strokes and other neurological diseases can cause vocal cord paralysis.

• #2 Vocal Cord Paralysis: Pathophysiology, Etiologies, and Evaluation

  https://www.ijhns.com/abstractArticleContentBrowse/IJHNS/27529/JPJ/fullText

  Recurrent laryngeal nerve injury from anterior approaches to the cervical spine is the most common complication of these procedures, quoted at 2-6%. […] Damage to the RLN following thyroid surgery is a well-known complication, having been recognized for over a century and being a common cause for litigation. […] The most common nonlaryngeal neoplasms causing RLN paralysis are thyroid, lung, oesophageal and mediastinal. […] The exact mechanism of endotracheal intubation-induced RLN paralysis remains unknown. […] Several viruses have been cited as causing RLN paralysis, however proving viral etiology remains difficult, as positive biochemical testing does not prove neural involvement nor causation. […] The clinician must always bear in mind unusual causes for vocal cord paralysis should the more common causes prove to be not responsible. […] Idiopathic etiologies have no cause by definition. […] Laryngeal electromyography (LEMG) is considered the gold standard investigation to diagnose and evaluate the type and degree of neurological injury in vocal cord paralysis.

• #2

  https://journals.lww.com/jolv/fulltext/2017/07020/postintubation_recurrent_laryngeal_nerve_palsy__a.1.aspx

  The mechanism of recurrent laryngeal nerve paralysis due to tracheal intubation is usually an indirect injury. […] The factors of indirect injury are said to include tracheal tube size, location of the cuff, fixing side of the tube, cuff pressure, curvature of tracheal tube, and intubation time. […] This compression of the recurrent nerve and its peripheral branches in the larynx causes degeneration and subsequent nerve paralysis. […] Insufficient microcirculatory supply to the nerve and its branches may cause ischemic neuronal degeneration and subsequent paralysis. […] An inflated cuff may compress the anterior branch of the recurrent laryngeal nerve, therefore, the cuff should be located at more than 15 mm below the vocal cords. […] Other types of endotracheal tubes are also known to cause vocal cord paralysis.

• #2 Vocal Cord Paralysis: Causes, Symptoms & Treatment

  https://my.clevelandclinic.org/health/diseases/17624-vocal-cord-paralysis

  Poisonous substances: Toxins, including lead, mercury and arsenic, can harm nerve tissue. […] Surgery: Surgeries in your head and neck, including thyroid gland removal (thyroidectomy), parathyroid surgery, heart surgery and cervical spine surgery, can lead to complications, like nerve injury. […] Tumors: Cancerous (malignant) tumors and noncancerous (benign) tumors can push on the nerves in your voice box, causing damage. […] Sometimes, a vocal cord can get paralyzed after a cold or upper respiratory infection. […] Treatment depends on the severity of the paralysis and your symptoms. […] If paralysis is mild, you may need voice therapy to improve how your vocal cords work. […] More severe vocal cord paralysis may require surgery. […] With unilateral vocal cord paralysis, providers often choose to delay surgery for up to a year to allow time for the condition to improve.

• #2 Vocal Cord Paralysis and its Etiologies: A – ProQuest

  https://www.proquest.com/scholarly-journals/vocal-cord-paralysis-etiologies-prospective-study/docview/1627083366/se-2

  Vocal cord paralysis is a common symptom of numerous diseases and it may be due to neurogenic or mechanical fixation of the cords. […] This study evaluates the causes of vocal cord paralysis. […] The causes of vocal cords paralysis were idiopathic paralysis (31.11%), tumors (31.11%), surgery (28.89%), trauma, brain problems, systemic disease and other causes (2.2%). […] Diagnosing initial disease is remarkable that in case of late diagnosis could result in serious symptoms or death such as malignant cancers. […] Recurrent laryngeal nerve function can be impaired due to pressure or pathology of the disease damaging the nerve leading to paralysis of the vocal cords. […] Malignant invasion to vagus nerve or recurrent laryngeal nerve invasion of malignant neoplasms can be generated by the thyroid neoplasms, lung cancer, esophagus carcinoma and mediastinal metastasis.

• #2 Vocal Cord Paralysis: Causes, Symptoms & Treatment

  https://my.clevelandclinic.org/health/diseases/17624-vocal-cord-paralysis

  Vocal cord paralysis involves one or both vocal cords (vocal folds) not moving as they should. […] With vocal cord paralysis, nerve damage prevents the muscles inside your vocal cords from opening and closing properly. […] Multiple conditions can damage the nerves that control how your vocal cords move, including: […] Autoimmune diseases: Diseases that interfere with how nerves communicate with muscles, such as myasthenia gravis (MG), can lead to vocal cord paralysis. […] Infections: Lyme disease, herpes, the Epstein-Barr virus and COVID-19 can cause inflammation that damages the nerves that control vocal cord movement. […] Injury: Trauma to your neck, head and chest can cause nerve damage. […] Neurological diseases: Conditions that involve nerve deterioration and damage, including multiple sclerosis (MS), Parkinsons disease and stroke, can impact the nerves that control your vocal cords.

• #2 Vocal Fold Motion Impairment in Neurodegenerative Diseases

  https://www.mdpi.com/2077-0383/13/9/2507

  The pathogenesis of VFMI in PD is not completely understood, but it is thought to involve a combination of motor impairments, neuromuscular dysfunction, and degenerative changes in the brainstem nuclei responsible for laryngeal muscle control, which contribute to paralysis or weakness. […] There are two plausible hypotheses for the pathophysiology of VFMI: (1) a severe loss of neurons in the nucleus ambiguus results in hypoactivity and neurogenic atrophy of the posterior cricoarytenoid muscle, which is the sole laryngeal abductor muscle, or (2) dystonia is induced by hyperactivity of the laryngeal adductor muscles. […] The mechanism behind VFMI in PSP involves neurodegenerative processes that affect the central nervous system. […] This condition is often misdiagnosed as PD initially, but it progresses more rapidly than PD.

• #2 Vocal Cord Paralysis – Ear, Nose, and Throat Disorders – Merck Manual Consumer Version

  https://www.merckmanuals.com/home/ear-nose-and-throat-disorders/laryngeal-disorders/vocal-cord-paralysis

  Paralysis can be caused by tumors, injuries, or nerve damage. […] Paralysis of one vocal cord can result from brain disorders, such as brain tumors, strokes, and demyelinating diseases (such as multiple sclerosis), or damage to the nerves that lead to the voice box (larynx). Nerve damage may be caused by noncancerous (benign) and cancerous (malignant) tumors; neck injury; many types of surgery that involve the neck or chest, such as surgical removal of the thyroid gland, spinal surgery, or heart surgery; a viral infection of the nerves; Lyme disease; neurotoxins (substances that poison or destroy nerve tissue), such as lead, mercury, and arsenic; or the toxins produced in diphtheria. The cause is unknown for some people. […] Paralysis of both vocal cords is a life-threatening disorder because the vocal cords cannot open enough to let air through properly. This paralysis can be caused by surgery of the spine through the front of the neck, surgical removal of the thyroid gland, insertion of a breathing tube into the windpipe (tracheal intubation), or diseases that affect the nerves and muscles (such as myasthenia gravis).

• #2 Paralysis (Unilateral) | Sean Parker Institute for the Voice

  https://voice.weill.cornell.edu/voice-disorders/paralysis-unilateral

  Vocal fold paralysis is immobility of a vocal fold because of damage or dysfunction of its principal nerve. […] Most unilateral paralysis of the vocal folds happens for one of three reasons: nerve injury during a number of common surgeries, pressure on the nerve (for instance from a tumor growing next to it), or inflammation that stops the nerve from working (usually attributed to viral infection). […] Vocal fold paralysis may be an inadvertent result of several common surgeries, listed below. […] In cases of paralysis in persons who have not had any of the above procedures, tumors are the most serious concern, with health consequences that reach far beyond voice. […] In some 15-20% of cases, no reason is found for the vocal fold paralysis, even after appropriate radiologic studies. These are called idiopathic, and usually attributed to viral inflammation.

• #2 Revisiting CT Signs of Unilateral Vocal Fold Paralysis: A Single, Blinded Study | American Journal of Neuroradiology

  http://www.ajnr.org/content/43/4/592

  Several CT findings are thought to be indicative of vocal cord paralysis; however, these signs have never been validated in a blinded fashion. […] This disease process develops as a result of injury to the vagus nerve or recurrent laryngeal nerve, a branch of the vagus nerve. Up to 40% of cases are idiopathic. […] In the absence of a history of a neck or cervical spinal operation, laryngeal trauma, or known malignancy, the standard diagnostic work-up includes CT from the skull base through the mediastinum to assess a lesion along the course of the nerve. […] Although cord palsy is often diagnosed clinically, up to 30% of cases may be asymptomatic and clinically unsuspected. […] There are many imaging signs to suggest vocal cord paralysis with varying degrees of sensitivity and specificity.

• #2 Vocal cord paralysis | PPT

  https://www.slideshare.net/slideshow/vocal-cord-paralysis/26355965

  Vocal cord paralysis is defined as total interruption of nerve impulses resulting in no movement of laryngeal muscles, while paresis is partial interruption causing weak movement. […] Causes of laryngeal paralysis can be supranuclear, nuclear, related to high or low vagal lesions, or systemic. […] In unilateral recurrent laryngeal nerve paralysis, the vocal cord assumes a median position and does not move laterally on inspiration. […] Bilateral paralysis causes stridor and dyspnea due to […] The vocal cords thus assumes a median or paramedian position doesn’t move laterally on deep inspiration. […] Unilateral injury to recurrent laryngeal nerve results in ipsilateral paralysis of all the intrinsic muscles of larynx except the cricothyroid. […] The voice in unilateral paralysis gradually improves due to compensation by healthy cord which crosses midline to meet paralysed one. […] Bilateral paralysis from neuritis causes both cords to be in the paramedian position, resulting in breathing difficulties that worsen with exertion. […] Treatment may include cord lateralization procedures like arytenoidectomy or thyroplasty to improve breathing.

• #2 Vocal Cord Paralysis | IntechOpen

  https://www.intechopen.com/chapters/81705

  Wegner and Grossman hypothesis explains the median and paramedian position of cords after RLN palsy, on the basis that cricothyroid muscle that receives supply from superior laryngeal nerve takes over it has adductor and tensor function. […] RLN damage is the most common cause of bilateral vocal cord paralysis. Combined paralysis of RLN and SLN is also possible and is seen post-thyroidectomy surgeries due to iatrogenic trauma. […] Bilateral vocal cord paralysis can be caused by injury to the vagus nerve near its origin or anywhere along its course or injury to its branches RLN and SLN through neck, thorax, and abdomen. […] Injury to the RLN is most common, classically leaving the vocal cords in a median position in case of bilateral vocal cord paralysis. […] Injury to the SLN will lower the pitch of the voice and can lead to a bowing deformity of the vocal cords due to a loss of tone from the dennervated cricothyroid muscles. […] A high vagal injury can leave the cord in a nearly fully abducted position.

• #2 Vocal cord paralysis information – Airway Unit, Service of Otorhino-laryngology – CHUV

  https://www.chuv.ch/en/voies-aeriennes/orva-home/patients-and-families/conditions-we-treat/vocal-cord-paralysis-information

  A bilateral paralysis may be associated with other congenital anomalies and require tracheostomy in 50% cases. […] An MRI / CT scan will be organised to evaluate the exact cause of the paralysis. Further, a panendoscopy (microlaryngoscopy, tracheo-bronchoscopy, esophagoscopy) is performed under general anesthesia to look at the entire aero-digestive tract. […] If there is bronchoaspiration and crippling voice change, the paralysed cord could be medialised (brought in the midline to make contact with the opposite cord) by an operation thyroplasty or endoscopic cord medialisation procedures. […] Both vocal cord paralysis presents with severe breathing difficulty and is an emergency.

• #2 Pathophysiology of Recurrent Laryngeal Nerve Injury | Ento Key

  https://entokey.com/pathophysiology-of-recurrent-laryngeal-nerve-injury/

  The risk of synkinesis increases with the degree of nerve injury. […] The prognosis for recovery of motor function is better when the nerve lesion is more distal, closer to the target muscle. […] The strong propensity for regeneration of the recurrent laryngeal nerve is well documented in the literature.

• #2 Vocal Cord Paralysis: Pathophysiology, Etiologies, and Evaluation

  https://www.ijhns.com/abstractArticleContentBrowse/IJHNS/27529/JPJ/fullText

  Vocal fold paralysis often leads to significant morbidity including dysphonia, dysphagia and aspiration. […] An appropriate understanding of the pathophysiology, etiologies, and a systematic method of evaluation are essential for discussing prognosis and offering patients appropriate treatments. […] Damage or injury to these nerves may result in vocal fold paresis or paralysis. […] Vocal fold paralysis implies complete vocal fold immobility due to neurological injury. […] It is important to differentiate between nerve conduction block and presence of axonal injury for prognostication purposes when possible. […] Most surgically induced nerve injuries are the result of pressure, crushing or heating intraoperatively, leaving the nerve macroscopically intact. […] Neuropraxia is the mildest form of injury, in which the Schwann cells are injured but the axon integrity is maintained, often resulting in a conduction block lasting for 6-8 weeks whilst the Schwann cells repair.

• #2 Vocal Fold Paralysis Causes, Diagnosis, Symptoms, & Treatment

  https://throatdisorder.com/voice-disorders/vocal-fold-paralysis/

  Vocal fold paralysis is typically due to a problem with the recurrent laryngeal nerve, the nerve that controls motion of the vocal fold. […] When the nerve to the vocal fold is affected, it leaves the vocal cord immobile and paralyzed. […] Swelling of the nerve for unknown reasons. This is also known as idiopathic vocal cord paralysis and occurs is responsible for paralysis approximately 30% of the time. […] The symptoms of vocal fold paralysis occur because the vocal folds are unable to meet in the midline. Sound production is weak and patients feel out of breath because they have a constant air escape from the lungs through the voice box. […] In cases in which vocal fold paralysis is potentially reversible, such as a when idiopathic, or when the nerve is inflamed (but not cut) after surgery, paralysis may resolve up to one year after injury.

• #2 Stem cell implants offer hope for vocal cord paralysis – Otolaryngology–Head & Neck Surgery

  https://oto.wustl.edu/stem-cell-implants-offer-hope-for-vocal-cord-paralysis/

  Vocal cord paralysis occurs when nerve impulses to the larynx are disrupted, causing problems with speech and breathing. […] The nerve to the vocal cords can be injured in a variety of ways, including surgical injury (especially thyroid surgery), tumors and viral infections. […] According to Dr. Paniello, adult muscle stem cells (MSCs), implanted into a muscle that has lost its nerve, can improve muscle function, in part by regrowth of the nerve for that muscle. […] The desired outcome is restoration of nerve function, but nerves grow slowly, so it takes several months to know whether or not an intervention has helped. […] Implanting MSCs into the vocal cord closing muscles improves that functional recovery to 128% of baseline. Implanting MSCs into the opening muscles also showed enhanced improvement, up to 83% of normal.

• #3 Unilateral Vocal Fold Paralysis: Practice Essentials, History of the Procedure, Problem

  https://emedicine.medscape.com/article/863779-overview

  Unilateral vocal fold paralysis (UVFP) occurs from a dysfunction of the recurrent laryngeal or vagus nerve innervating the larynx. […] The recurrent laryngeal nerve is responsible for both abduction and adduction of the vocal fold. The recurrent laryngeal nerve originates from the vagus nerve, which originates from the brainstem (nucleus ambiguous in the medulla) and travels along the carotid sheath (with the jugular vein and internal carotid artery). The left vagus nerve gives rise to the left recurrent laryngeal nerve as the vagus crosses the arch of the aorta. The left recurrent laryngeal nerve then loops under the ligamentum arteriosum and travels cephalad in the tracheoesophageal groove until it penetrates the larynx to innervate the intrinsic muscles of the larynx. […] Because of the circuitous nature of the recurrent laryngeal nerve, multiple disease processes and operative procedures put these important nerves at risk, often resulting in vocal fold paralysis.

• #3 Vocal Cord Paralysis | IntechOpen

  https://www.intechopen.com/chapters/81705

  Wegner and Grossman hypothesis explains the median and paramedian position of cords after RLN palsy, on the basis that cricothyroid muscle that receives supply from superior laryngeal nerve takes over it has adductor and tensor function. […] RLN damage is the most common cause of bilateral vocal cord paralysis. Combined paralysis of RLN and SLN is also possible and is seen post-thyroidectomy surgeries due to iatrogenic trauma. […] Bilateral vocal cord paralysis can be caused by injury to the vagus nerve near its origin or anywhere along its course or injury to its branches RLN and SLN through neck, thorax, and abdomen. […] Injury to the RLN is most common, classically leaving the vocal cords in a median position in case of bilateral vocal cord paralysis. […] Injury to the SLN will lower the pitch of the voice and can lead to a bowing deformity of the vocal cords due to a loss of tone from the dennervated cricothyroid muscles. […] A high vagal injury can leave the cord in a nearly fully abducted position.

Zobacz więcej