Intraoperative neuromonitoring for thyroid malignancy surgery : technical notes and results from a retrospective series

This study evaluates the role of intraoperative neuromonitoring (IONM) for thyroidectomy performed in cancer patients with emphasis on postoperative recurrent laryngeal nerve paralysis (RLNP). The study is a retrospective series comprising 76 thyroidectomy alone (control group) versus 76 thyroidectomy with IONM. In the control group the laryngeal nerves have been identified by visualization solely. In the IONM group both vagal nerve and RLN have been localized and monitored during thyroid resection. The main surgical outcome was RLN morbidity. All patients undergo pre- and postoperative laryngeal examination. Overall RLN morbidity was 3.9% in the IONM group and 9.2% in the control group (P < 0.05). There have been two cases of permanent RLNP (2.6%) in the control group and one in the IONM group (1.3%), one case of bilateral RLN injury in the control group. The incidences of temporary RLNP in the IONM group have been 2.6 versus 6.5% in the control group. IONM is an effective procedure in thyroid cancer patients.