A special endotracheal tube with right and left electrodes is placed near the muscles of the vocal cords which are innervated by the recurrent laryngeal nerve. These electrodes are connected to a computer that analyzes the electric activity and displays the electromyographic (EMG) activity of the vocal cords ( muscle electrical potentials) on a screen.
During the operation, the electrical activity (EMG response) of the nerve is continuously monitored. If the recurrent laryngeal nerve is stimulated or disturbed, an electrical impulse is detected by the monitoring technician who alerts the surgeon.
Intra-operative monitoring offers added security for the patient without delaying the operation or hindering the surgeon in any way.
Anatomy of the recurrent laryngeal nerve and its relationship to the thyroid gland.