fig1

Figure 1. Learning from IONM. The causes of RLNP were revealed by intra-operative video analysis. A, B: in the first case, the electric scalpel touched the RLN before it was recognized (A), resulting in a loss of signal at this point (B). Thermal damage was deemed to be the cause of paralysis in this case. C, D: in the second case, the surgeon compressed the area around the RLN to achieve hemostasis (C). Signal loss occurred at this point (C) and compression of the nerve between the forceps and trachea was determined as the cause of paralysis. E, F: in the third case, excessive traction damaged the RLN at the edge of trachea (E), leading to signal loss. IONM: intraoperative neural monitoring; RLN: recurrent laryngeal nerve; RLNP: recurrent laryngeal nerve paralysis