Facial-nerve and vocal-cord monitoring during otoneurosurgical operations.

We describe a newly developed instrument to monitor facial muscles and vocal-cord function during neurosurgical and otoneurosurgical operations. The device (Myo-Alarm) transforms into acoustic signals the pressure variations that are induced by facial muscles and vocal-cord contractions on air-inflated rubber sensors that are positioned, respectively, beneath the superior lip and between the vocal cords. It represents an effective and dependable method to monitor facial and vocal-cord functional preservation during surgery.