ABSTRACT

Paralysis of one vocal cord causes hoarseness with a breathy quality to the voice. The cough loses its characteristic sharpness and becomes more of a roaring sound, reminiscent of the cough produced by a cow and therefore known as a bovine cough. There may be difficulty in swallowing because of associated paralysis of the cricopharyngeus muscle. If both vocal cords are paralysed the voice is weak and breathy, but there may also be obstruction of the upper airway. This very much depends on the position in which the vocal cords are lying. If they lie well away from the mid-line, the voice is very weak but the airway is usually satisfactory. If they lie close to the mid-line the voice may be stronger, but the airway is poor and there is usually stridor at least on exertion.