Role of intraoperative neuromonitoring of the recurrent laryngeal nerves during thyroid reoperations of recurrent goiter

Reoperations of the thyroid gland are challenging to any surgeon. Such procedures are technically difficult and involve higher risk of complications than primary procedures. Recurrent laryngeal nerve (RLN) palsy is one of such complications The aim of the study was to evaluate the effectiveness of intraoperative neuromonitoring (IONM) in preventing RLN palsy during recurrent goiter operations. Material and methods. We retrospectively analyzed the results of thyroid reoperation performed at the Department of Endocrine, General and Vascular Surgery of Medical University of Lodz in the period from January 2014 to June 2016. The study included 80 patients, who were divided into 2 groups: group A consisted of 27 patients, who had undergone surgery with the use of IONM, while group B included 53 patients, in whom RLN was identified visually. During statistical analysis we took into account the number of nerves at risk, not the number of patients. There were 47 nerves at risk In group A and 86 in group B. We analyzed whether application of IONM had any effect on the frequency of RLN palsy and procedure duration. Results. The frequency of RLN palsy was 10.64% (5/47) in group A and 15.12% (13/86) in group B (no statistical significance, p=0,47). Mean operation time was shorter in group B 71.29 ± 17.125 minutes vs. 75.75 ± 17.94 minutes in group A (no statistical significance, p=0,377). Conclusion. Use of IONM did not significantly reduce the occurrence of RLN palsy and procedure duration.