Abstract
Paresis of the recurrent laryngeal nerve (RLN) is one of the serious complications of thyroid and parathyroid gland surgery. The intraoperative neural monitoring (IONM) enables to verify the functionality of RLN.
The aim of this study is to compare the incidence of postoperative RLN palsy in patients who underwent surgery with and without the use of IONM RLN and to evaluate the positive and negative predictive values, sensitivity, specificity and accuracy of the method. Methods: Retrospective analysis of thyroid gland surgeries performed within the period from 1. 7. 2016 to 1. 7. 2018.
A total of 467 operations were performed (780 nerves exposed). One hundred and thirty procedures (215 nerves) were carried out without IONM (group A).
In total, 337 procedures (565 nerves) were performed with IONM (group B). Results: In group A, unilateral postoperative RLN paresis occurred in 7 cases (3.26%); 6 of them were temporary (2.79%) and 1 was permanent (0.47%).
In group B, unilateral postoperative RLN paresis occurred in 33 cases (5.84%); 32 of them were temporary (5.66%) and 1 was permanent (0.18%). The incidence of postoperative RLN paresis related to the use of IONM was not considered statistically significant. (Chi-square test: P = 0.146; Fisher's exact test: P = 0.2015, P = 0.4715).
The sensitivity, specificity, positive predictive value, negative predictive value and accuracy were 78.79%, 99.25%, 86.67%, 98.69%, and 98.05%, respectively. There was no case of bilateral postoperative RLN paresis.
Conclusion: There was no statistically significant difference in the incidence of postoperative RLN palsy in patients who underwent surgery with IONM compared to the group without IONM. The high negative predictive value, specificity and accuracy indicate high reliability of the method.
The IONM provides the surgeon with valuable information regarding the functional status of the nerve. This knowledge allows for changing the operative strategy during the procedure.