Unilateral Vocal Cord Paralysis

Nora Malaisrie, M.D.

Faculty Discussant: Natasha Mirza, M.D.

Thursday, July 24, 2008

Otorhinolaryngology: Head and Neck Surgery at PENN Excellence in Patient Care, Education and Research since 1870

Introduction

    Affects quality of life Potential morbidity and mortality A sign of a disease process with multiple etiologies, necessitating thorough evaluation Multiple therapeutic options that must be tailored to the patient

Anatomy

    Upper motor neurons from cerebral cortex to nucleus ambiguus in the medulla Lower motor neurons from nucleus ambiguus exit the medulla as the vagus nerve Vagus nerve exits the skull base via the jugular foramen Branches – Pharyngeal branch – Superior laryngeal nerve – Recurrent laryngeal nerve

Anatomy

  Recurrent laryngeal nerve – 0.5% right non recurrent laryngeal nerve Muscles – Lateral cricoarytenoid – Posterior cricoarytenoid – Thyroarytenoid – Interarytenoid

Etiology

 Dysfunction at – Brain and brainstem nuclei – Vagus nerve – Recurrent laryngeal nerve

Etiology: Neurologic

       Stroke CNS tumor Diabetic neuropathy Amyotrophic lateral sclerosis (ALS) Parkinson disease Myasthenia gravis Guillain-Barre syndrome

Etiology: Tumor infiltration or mass compression

    Skull base Thyroid Esophagus Lung

Etiology: Systemic disease

         Systemic lupus erythematosus Sarcoidosis Amyloidosis Tuberculosis Charcot-Marie-Tooth Mitochondrial disorders Porphyria Polyarteritis nodosa Silicosis

Etiology: Medications

 Vinca alkaloids – Vincristine and vinblastine – Unilateral or bilateral – Dose related – Resolves with dose adjustment or cessation

Etiology: Traumatic

 Iatrogenic: Surgical – Thyroidectomy – Anterior cervical spine procedures – Esophagectomy – Thymectomy – Carotid endarterectomy – Cardiothoracic surgery     Aortic surgery Coronary artery bypass grafting Pulmonary lobar resection Mediastinoscopy  Iatrogenic: Non-surgical – Endotracheal intubation  Arytenoid dislocation, subluxation  Tapia’s syndrome – Nasogastric tube placement 1  Non-iatrogenic – Blunt or penetrating trauma to the neck Brousseau et al. A rare but serious entity: nasogastric tube syndrome. Otolaryngol Head Neck Surg . 2006 Nov;135(5): 677-679.

Etiology: Idiopathic

   Not well understood Possible infectious cause – Lyme disease – Tertiary syphilis – Epstein-Barr virus – Herpes simplex virus Type I Diagnosis of exclusion – Urquhart et al. showed that 26% of patients with a diagnosis of idiopathic VCP had a preexisting neurologic condition and 20% developed a subsequent CNS condition.

1 Urquhart et al. Idiopathic vocal cord palsies and associated neurological conditions. Arch Otolaryngol Head Neck Surg . 2005 Dec;131(12):1086-9.

Etiology

 In a retrospective analysis of 363 patients, Rosenthal et al. showed that unilateral VCP was caused by 1. Surgery (46%) 2. Idiopathic (18%) 3. Malignancy (13%) • Lung was most common Rosenthal et al. Vocal Fold Immobility: A Longitudinal analysis of Etiology Over 20 Years. Laryngoscope . 2007 Oct;117(10): 1864-1870.

Etiology

 Rosenthal et al. showed that surgical causes of unilateral vocal cord immobility were the result of 1.

Non-thyroid surgeries (67%) • • • Anterior cervical spine (15%) Carotid endarterectomy (11%) Cardiac (9%) 2.

• • • Thyroid surgeries (33%) Thyroid (26%) Parathyroid (6%) Thyroid and parathyroid (1%) Rosenthal et al. Vocal Fold Immobility: A Longitudinal analysis of Etiology Over 20 Years. Laryngoscope . 2007 Oct;117(10): 1864-1870.

Etiology

 Rosenthal et al. compared unilateral VCP from 1985-1995 to 1996-2005 – Surgical causes doubled – Malignant causes decreased Rosenthal et al. Vocal Fold Immobility: A Longitudinal analysis of Etiology Over 20 Years. Laryngoscope . 2007 Oct;117(10): 1864-1870.

Etiology

 Rosenthal et al. compared their study to previous studies to evaluate the changing etiology of unilateral VCP.

– Increase in surgical causes, with a greater proportion attributable to non-thyroid surgeries – Decrease in malignant causes Rosenthal et al. Vocal Fold Immobility: A Longitudinal analysis of Etiology Over 20 Years. Laryngoscope . 2007 Oct;117(10): 1864-1870.

Evaluation – History

   Symptoms – Voice changes    Hoarseness to aphonia Compensatory voice changes Vocal fatigue, neck pain – Aspiration – Weak, ineffective cough Past medical and surgical history Social history

Evaluation – Physical Exam

  Cranial nerve exam Nasopharyngolaryngoscopy – Vocal cord asymmetry – Horizontal and vertical position – Glottic gap – Poooled secretions – Aspiration – Maximal phonation time (MPT) – Supraglottic hyperfunction

Evaluation – Physical Exam

 Videostroboscopy – Increased amplitude of vibration – Vocal fold height difference – Vocal process contact

Evidence Based Medicine Levels and Grades

Evaluation – Labs

  In a survey of 84 otolaryngologists, Merati et al. found that – 20% found that serum testing was necessary – The most commonly ordered labs were RF, Lyme titer, ESR, ANA 1 Routine labs not supported by the literature if cause unknown.

2,3 1. Merati et al. Diagnostic testing for Vocal Fold Paralysis: Survey of Practice and Evidence-Based Medicine Review. Laryngoscope. 2006 Sept; 116: 1539-1552.

2. Terris et al. Contemporary evaluation of unilatereal vocal cord paralysis. Otolaryngol Head Neck Surg. 1992 Jul;107(1):84-90. 3. MacGregor et al. Vocal Fold palsy: a re-evaluation of investigations. J Laryngol Otol. 1994;108:193-19.

Evaluation

  Assess swallow function and aspiration – Modified barium swallow – Functional endoscopic evaluation of swallowing (FEES) No additional work up required if clear cut etiology

Evaluation – Imaging

  Modalities – CXR: May be most useful and cost-effective.

– CT with contrast: May evaluate the entire course of the RLN.

– MRI: May be useful in patients with polyneuropathy Literature does not demonstrate superiority of any single modality 1. Merati et al. Diagnostic testing for Vocal Fold Paralysis: Survey of Practice and Evidence-Based Medicine Review. Laryngoscope. 2006 Sept; 116: 1539-1552.

2. Terris et al. Contemporary evaluation of unilatereal vocal cord paralysis. Otolaryngol Head Neck Surg. 1992 Jul;107(1):84-90.

3. Glazer et al. Extralaryngeal causes of vocal cord paralysis: CT evaluation. AJR am J Roentgenol 1983;141:527-531.

4. ElBadawey et al. Prospective study to assess vocal cord palsy investigations. Otolaryng Head Neck Surg 2008; 138:78-790.

Evaluation – Laryngeal electromyography (LEMG)

1.

2.

   Needle electrode placement into thyroarytenoid and cricothyoid muscle Assess – Muscle at rest – Voluntary motor unit recruitment May not be useful in diagnosis Munin et al. Laryngeal electromyography: diagnostic and prognostic applications. Otolaryngol Clin North Am. 2000 Aug;33(4):759-70. Sataloff et al. Practice parameter: laryngeal electromyography (an evidence-based review). Otolaryngol Head Neck Surg 2004; 130: 770-779.

Evaluation – LEMG

  Munin et al. reported that LEMG obtained 1-6 mo from onset may be helpful in determining prognosis.

1 – Prognosis good if there is absent spontaneous activity and normal recruitment with normal motor unit morphology – Prognosis poor if there is spontaneous activity with absent recruitment and presence of fibrillations 2 Wang et al. reported that LEMG obtained 2-6 mo from onset have a sensitivity and PPV of 93% and accuracy of 87%.

2 1.

2.

3.

Munin et al. Laryngeal electromyography: diagnostic and prognostic applications. Otolaryngol Clin North Am. 2000 Aug;33(4):759-70. Koufman et al. Diagnostic laryngeal electromyography: The Wake Forest experience 1995-1999. Otolaryngol Head Neck Surg. 2001 Jun;124(6):603-6.

Wang et al. Prognostic indicators of unilateral vocal fold paralysis. Arch Otolaryngol Head Neck Surg. 2008 Apr;134(4):380-8.

Differential Diagnosis

  Cricoarytenoid fixation – Caused by  Joint subluxation/dislocation with ankylosis  Joint fixation by rheumatoid arthritis or gout – Normal EMG – Direct laryngoscopy Laryngeal malignancy

Treatment

  Goal: Improve voice and prevent aspiration. Patient factors affect treatment strategies.

– Presence of aspiration – Nature of nerve injury – Vocal demands – Medical comorbidities – LEMG findings Strategies: – Observation for 6-12 months – Speech and swallow therapy – Surgical intervention   Temporary: Vocal fold injection Permanent: Vocal fold injection with durable material, medialization thyroplasty +/- arytenoid adduction or laryngeal reinnervation

Treatment – Speech and swallow

    Provides voice therapy Teaches vocal hygiene and compensatory strategies Identifies and eliminates counterproductive compensatory strategies Pre-operative and post-operative assessment

Treatment – Injection laryngoplasty

  Injection with temporary materials temporizes the voice until return of function Many materials available for augmentation O’Leary et al. Injection Laryngoplasty. Otolaryngol Clin N Am 2006;39:43-54.

Treatment – Injection laryngoplasty

 Method: Under local anesthesia via transcutaneous or oral approach with NPL – Adv: Useful for poor surgical candidates, voice feedback – Disadv: Pt discomfort

Treatment – Injection laryngoplasty

Pre-injection Post-injection

Treatment – Injection laryngoplasty

  Method: Under general anesthesia via direct laryngoscopy – Adv: Patient comfort, improved precision – Disadv: No voice feedback Complications: Under injection, over-injection, improper placement, foreign body reaction

Treatment – Medialization thyroplasty

   Direct medialization of the vocal cord Performed alone or with arytenoid adduction or reinnervation procedure Implant material – Carved or prefabricated Silastic implant – Hydroxyapatite implant – Gore-Tex strips

Treatment – Medialization thyroplasty

   Adv: Local anesthesia, voice feedback, reversible, vocal fold integrity preserved Disadv: Open procedure, technically difficult, closure of posterior gap limited Complications: Penetration of laryngeal mucosa, infection, chondritis, implant migration, airway obstruction, undercorrection

Treatment – Arytenoid adduction

1.

2.

   Adjunct to medialization thyroplasty if large posterior glottic gap or vocal folds at different levels Kraus et al. showed that when combined with a medialization thyroplasty, there was improvement in symptoms as well as voice parameters.

1 Mucullough et al. showed that when combined with medialization thyroplasty, functional results exceeded the improvement attained with medialization alone.

2 Kraus et al. Arytenoid adduction as an adjunct to type I thyroplasty for unilateral vocal cord paralysis. Head Neck. 1999 Jan;21(1):52-9.

Mucullouch et al. Arytenoid adduction combined with Gore-Tex medialization thyroplasty. Laryngoscope. 2000 Aug;110(8):1306-11.

Treatment – MT + AA

 Complications of medialization thyroplasty with arytenoid adduction – Abraham et al. compared ML + AA patients to ML alone and found no statistical difference.

Abraham et al. Complications of type I thyroplasty and arytenoid adduction. Aug;111(8):1322-9.

Laryngoscope . 2001

Treatment – Laryngeal reinnervation

     Goal: Increase bulk and tone Indications: Poor chance of spontaneous recovery Nerve characteristics – RLN – Ansa cervicalis Types – Neuromuscular pedicle – Nerve-nerve anastamosis May be combined with temporary injection laryngoplasty until reinnervation

Treatment – Laryngeal Reinnervation

 Nerve muscle pedicle (NMP) – Nerve with portion of motor units transferred to a denervated muscle.

– Thyrotomy performed to place the NMP to the lateral cricoarytenoid muscle.

– Tucker et al. reported improvement in voice quality and restoration of adduction.

1 Tucker et al. Long-term results of nerve-muscle pedicle reinnervation for laryngeal paralysis. Ann Otol Rhinol Laryngol 1989;98:674-676.

Treatment – Laryngeal Reinnervation

   Ansa cervicalis to RLN – Provides weak tonic innervation to intrinsic laryngeal muscles – Adv: Extralaryngeal, no permanent implant material, does not affect subsequent procedures – Disadv: Deeper dissection, requires intact nerves , delay in voice improvement Crumley reported improved vocal quality and restoration of the mucosal wave.

1 Lorenz et al. reported improved vocal quality as well as glottic closure and vocal fold edge straightening.

2 1.

2.

Crumley. Update: ansa cervicalis to recurrent laryngeal nerve anastomosis for unilateral laryngeal paralysis. Laryngoscope. 1991 Apr;101(4 Pt 1):384-388. Lorenz et al. Ansa cervicalis-to-recurrent laryngeal nerve anastomosis for unilateral vocal fold paralysis: experience of a single institution. Ann Otol Rhinol Laryngol. 2008 Jan;117(1):40-5.

Conclusion

   Unilateral vocal cord paralysis affects quality of life and may cause significant morbidity Thorough evaluation is mandatory to determine etiology if initially unclear Many treatment options are available which are tailored to patient

Acknowledgements

  Natsha Mirza, M.D.

Lauren Campe, M.S., CCC-SLP

References

                    Cummings: Bailey: Otolaryngology: Head & Neck Surgery , 4th ed.

Head and Neck Surgery – Otolaryngology Rubin et al. Vocal Fold Paresis and Paralysis. Sept; 116: 1539-1552.

, 4 th ed.

Otolaryngol Clin N Am . 2007 Oct; 40(5): 1109-1131.

Urquhart et al . Idiopathic vocal cord palsies and associated neurological conditions. Dec;131(12):1086-9.

Brousseau et al. A rare but serious entity: nasogastric tube syndrome.

Arch Otolaryngol Head Neck Surg Otolaryng Head Neck Surg Rosenthal et al. Vocal Fold Immobility: A Longitudinal analysis of Etiology Over 20 Years. . 2005 . 2006 Nov;135(5): 677-679.

Laryngoscope . 2007 Oct;117(10): 1864-1870.

Merati et al. Diagnostic testing for Vocal Fold Paralysis: Survey of Practice and Evidence-Based Medicine Review. Laryngoscope. 2006 Terris et al. Contemporary evaluation of unilatereal vocal cord paralysis. MacGregor et al. Vocal Fold palsy: a re-evaluation of investigations. Otolaryngol Head Neck Surg J Laryngol Otol ElBadawey et al. Prospective study to assess vocal cord palsy investigations. Munin et al. Laryngeal electromyography: diagnostic and prognostic applications. . 1994;108:193-19.

Otolaryng Head Neck Surg 2008; 138:78-790.

Otolaryngol Clin North Am . 2000 Aug;33(4):759-70.

Sataloff et al. Practice parameter: laryngeal electromyography (an evidence-based review). 779.

. 1992 Jul;107(1):84-90. Otolaryngol Head Neck Surg 2004; 130: 770 Koufman et al. Diagnostic laryngeal electromyography: The Wake Forest experience 1995-1999. Jun;124(6):603-6.

Wang et al. Prognostic indicators of unilateral vocal fold paralysis. al. Injection Laryngoplasty. Otolaryngol Clin N Am 2006;39:43-54.

Otolaryngol Head Neck Surg Arch Otolaryngol Head Neck Surg . 2008 Apr;134(4):380-8. O’Leary et Kraus et al. Arytenoid adduction as an adjunct to type I thyroplasty for unilateral vocal cord paralysis. Head Neck . 2001 . 1999 Jan;21(1):52-9.

Mucullouch et al. Arytenoid adduction combined with Gore-Tex medialization thyroplasty. Laryngoscope. 2000 Aug;110(8):1306-11.

Abraham et al. Complications of type I thyroplasty and arytenoid adduction. Laryngoscope. 2001 Aug;111(8):1322-9.

Tucker et al. Long-term results of nerve-muscle pedicle reinnervation for laryngeal paralysis. Ann Otol Rhinol Laryngol 1989;98:674-676.

Crumley. Update: ansa cervicalis to recurrent laryngeal nerve anastomosis for unilateral laryngeal paralysis. Laryngoscope. 1991 Apr;101(4 Pt 1):384-388. Lorenz et al. Ansa cervicalis-to-recurrent laryngeal nerve anastomosis for unilateral vocal fold paralysis: experience of a single institution. Ann Otol Rhinol Laryngo l. 2008 Jan;117(1):40-5.