Aphonia is defined as the inability to produce voiced sound. A primary cause of aphonia is bilateral disruption of the recurrent laryngeal nerve, which supplies nearly all the muscles in the larynx. Damage to the nerve may be the result of surgery (e.g., thyroidectomy) or a tumor. Aphonia means "no sound." In other words, a person with this disorder has lost his/her voice.

Psychogenic aphonia is often seen in patients with underlying psychological problems. Laryngeal examination will usually show bowed vocal folds that fail to adduct to the midline during phonation. However, the vocal folds will adduct when the patient is asked to cough. Treatment should involve consultation and counseling with a speech pathologist and, if necessary, a psychologist.

Injuries are often the cause of aphonia. Minor injuries can affect the second and third dorsal area in such a manner that the lymph patches concerned with coordination become either atrophic or relatively nonfunctioning. Tracheotomy can also cause aphonia.

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