Intraoperative Neurophysiological Monitoring for Endoscopic Endonasal Approaches to the Skull Base: A Technical Guide

Figure 3

Electromyographic train activity. (a) Examples of A-trains of various duration and frequency. (b) Waveforms defined as B-trains with spikes (), and B-trains with bursts () as predominant single components. The lowest tracing represents irregular EMG activity, called a C-train. C-trains are frequently recorded from laryngeal muscles at rest. The presence elsewhere is evidence of muscle tension and suggest insufficient sedation. Of these different forms of S-EMG activity, only A-trains are associated with neural injury. Figure from Romstöck et al. [29], with permission.

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