Fig. 1
Intraoperative T-NRT values in all groups: Groups 532 (n = 50), 512 (n = 47) and 522 (n = 43). The “+” stands for significant difference between groups 532 and 512. The “*” represents a significant difference between groups 532 and 522. Error bars represent the standard deviation (SD). The mean NRTs proved to be lower in each electrode in group 532 when compared with both control groups. The difference was significant in 5 measured electrodes when compared with 522 and 3 measured electrodes when compared with 532 (t-probe: p < 0.05). Grand T532–512 means statistical comparison between groups 532 and 512. Grand T532–522 means statistical comparison between groups 532 and 522