=====Free running electromyography=====
Significantly higher Free running electromyography (frEMG) activity was observed following saline injection than for the other solutions (p < 0.01). For frEMG activity ratios of ≥ 50 %, there was a trend towards a greater likelihood of persistent AMRs. When frEMG activity decreased after MVD in the mentalis muscles, FMEP amplitude ratios were significantly smaller than when it did not (65 vs. 94 %, p < 0.05).

Changes in intraoperative frEMG, AMRs, and FMEPs likely reflect a component of the normalization of hyper-excitability of the facial nerve by MVD for HFS
((Fukuda M, Takao T, Hiraishi T, Fujii Y. Free-running EMG monitoring during
microvascular decompression for hemifacial spasm. Acta Neurochir (Wien). 2015 Jul
5. [Epub ahead of print] PubMed PMID: 26143309.)).