In Japan, vocal Cord Paralysis is managed by ents. Vocal cord paralysis is a loss of function of one or both vocal folds caused by injury to the recurrent laryngeal nerve, the superior laryngeal nerve, or the vagus, presenting as breathy or weak voice, swallowing difficulty, and a higher risk of aspiration. Iatrogenic injury during thyroid, parathyroid, cervical spine, esophageal, cardiothoracic, or carotid surgery is the leading cause in adults, followed by malignant tumors (especially lung), idiopathic paralysis, intubation injury, viral neuropathy, and stroke.
Vocal cord paralysis (ICD-10: J38.00 unspecified, J38.01 unilateral, J38.02 bilateral) is impairment of vocal fold motion caused by injury or dysfunction of the motor nerves controlling laryngeal muscles. The recurrent laryngeal nerve, a branch of the vagus (cranial nerve X), innervates all intrinsic laryngeal muscles except the cricothyroid; injury produces ipsilateral immobility of the affected vocal fold. The superior laryngeal nerve, also a branch of the vagus, innervates the cricothyroid and is responsible for vocal pitch control; its injury causes a weak, breathy voice and difficulty with high notes. Vagus injury proximal to both branches produces combined sensory and motor deficits including loss of sensation in the supraglottis (aspiration risk).
The key symptoms of Vocal Cord Paralysis are: Breathy, soft, hoarse voice that lacks projection — the hallmark of unilateral paralysis caused by air escaping through the gap between the immobile fold and the moving fold., Vocal fatigue with prolonged speaking, throat tightness, and effortful phonation; voice often improves with rest and worsens by the end of the day., Choking, coughing, or throat clearing during meals and especially with thin liquids (water, broth), indicating glottic insufficiency and aspiration risk., Weak, ineffective cough and reduced ability to clear secretions, raising the risk of aspiration pneumonia., Shortness of breath on exertion and reduced exercise tolerance from inefficient phonation and increased respiratory effort., Sensation of throat dryness, lump in throat (globus), or constant urge to clear the throat., Stridor (noisy breathing, especially inspiratory) at rest or on exertion in bilateral paralysis — may require urgent airway evaluation..
Diagnosis combines history, perceptual voice evaluation, flexible laryngoscopy, and targeted imaging or laboratory testing to identify the underlying cause. The history establishes the time course of symptoms, recent surgery, intubation, or trauma; smoking and cancer risk factors; respiratory and swallowing symptoms; and prior voice complaints. Perceptual voice evaluation by an experienced clinician or speech-language pathologist documents breathiness, roughness, strain, and reduced loudness using the GRBAS or CAPE-V scale. Flexible fiberoptic laryngoscopy is the cornerstone test, performed in the office in 5-10 minutes through the nose, and directly visualizes vocal fold motion during quiet breathing, sniff, phonation, and pitch glides. Stroboscopy adds slow-motion assessment of vibratory function and confirms findings. The position of the paralyzed fold (paramedian, intermediate, paramedian-lateral) and the gap with the contralateral fold guides treatment selection. Laryngeal electromyography (LEMG) is the only test that directly examines the nerve and helps distinguish neuropraxia (likely to recover) from denervation (unlikely to recover); it is performed 1-6 months after injury and guides decisions about temporary vs. permanent surgery. When no surgical or obvious cause is identified, contrast-enhanced CT or MRI from the skull base through the upper mediastinum is performed to look for malignancy, brainstem lesion, or compressive mass. Additional workup may include thyroid imaging and function tests, chest X-ray, swallow evaluation (modified barium swallow or FEES), and laboratory workup for Lyme disease, syphilis, sarcoidosis (ACE), autoimmune disease (ANA, ANCA), and vitamin deficiencies. Multidisciplinary evaluation with laryngology, speech pathology, and as needed neurology, oncology, and pulmonology yields the highest diagnostic accuracy.
Outcomes depend on cause and time course. Approximately 30-40% of idiopathic and post-viral cases recover spontaneously within 6-12 months; iatrogenic transient paralysis recovers in 50-70% within 6 months; permanent paralysis after thyroid surgery is 0.1-0.4%. Voice therapy and injection medialization restore acceptable voice in 80-90% of patients with persistent unilateral paralysis. Permanent surgical treatment (medialization laryngoplasty, arytenoid adduction, reinnervation) produces excellent voice outcomes in 80-95% of patients. Aspiration risk is reduced substantially by surgical medialization. For bilateral paralysis, airway management is the priority; quality of life depends on whether decannulation is achieved and at what cost to voice. Malignancy-related paralysis carries the prognosis of the underlying disease. Long-term outcomes are best with multidisciplinary care, treatment at high-volume centers, and adherence to voice therapy alongside surgical interventions.
Laryngologists (subspecialty-trained ENT surgeons) provide the highest level of diagnostic and surgical expertise for vocal cord paralysis. They perform stroboscopy, laryngeal EMG, office-based injections, and complex phonosurgical procedures. Speech-language pathologists trained in voice therapy are essential partners. For bilateral paralysis, malignancy-related cases, and revision surgery, referral to a high-volume academic laryngology program is recommended.
Find specialists →Spontaneous recovery, if it occurs, typically within 6-12 months of onset. Office injection medialization produces immediate voice change lasting 2-6 months. Voice therapy yields measurable improvement over 6-12 sessions. Permanent medialization laryngoplasty: voice improvement immediate, with optimization over 4-6 weeks. Reinnervation: benefit develops over 4-9 months as nerve regenerates. Bilateral paralysis surgical decannulation usually achieved after 1-2 endoscopic procedures.
Regular aerobic exercise is encouraged for general health and as adjunct to voice therapy. Avoid breath-holding (Valsalva) maneuvers and heavy lifting in the first 6 weeks after phonosurgical procedures. Vocal warm-ups before extended speaking and after surgery are recommended, supervised by a speech-language pathologist.
Choose a laryngologist (ENT with fellowship training in laryngology) at a high-volume voice center. Confirm in-office stroboscopy, injection capability, and access to voice therapy services. For bilateral paralysis, prefer a center performing reinnervation, posterior cordotomy, and complex airway reconstruction.
Medically reviewed by AIHealz Medical Editorial Board · May 13, 2026
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