Management of Bilateral Vocal Fold Paralysis, Injury of External Branch of Superior Laryngeal Nerve after Thyroid Surgery

Bilateral vocal fold paralysis (BVFP) refers to neurological causes of reduced or absent movement of both vocal folds.It is characterized by inspiratory dyspnea due to narrowing of the airway at the glottic level with both vocal folds assuming a paramedian position.It is an uncommon condition among patients who underwent thyroidectomy.However, BVFP can be life threatening especially when the onset is acute.Meanwhile, the preservation of the external branch of the superior laryngeal nerve (EBSLN) is also important during thyroidectomy.The EBSLN injury, which innervates the cricothyroid muscle, results in vocalization difficulty of high pitched sound and the frequent fatigue of voice.We will discuss the cases when BVFP and the injury of EBSLN may occur after thyroidectomy, and review the management for these cases including surgical options and voice therapy.