[Intraoperative Artery Wall Stimulating Electromyography during Microvascular Decompression Surgery to Treat Hemifacial Spasm:A Case Report].

OBJECTIVE: Microvascular decompression(MVD)surgery has been established as a standard treatment for hemifacial spasm. However, because decompression surgery results in unfavorable outcomes in some cases, a more critical monitoring strategy is required. To improve surgical outcome for hemifacial spasms, abnormal muscle response(AMR)has been proposed as a tool for intraoperative electrophysiological monitoring during MVD surgery. Here, we report a single case of surgical MVD monitoring using artery wall stimulating electromyography(AWS-EMG). AWS-EMG was developed as a new monitoring method in addition to AMR.

CASE DESCRIPTION: A 60-year-old woman was diagnosed with hemifacial spasm using magnetic resonance imaging and magnetic resonance angiography fusion imaging. We performed MVD surgery using AWS-EMG and AMR. We successfully identified AWS-EMG before decompression and confirmed immediate AWS-EMG loss after decompression. This behavior was consistent with AMR. After surgery, the patient showed no further symptoms of hemifacial spasm.

CONCLUSIONS: In addition to AMR, AWS-EMG might be a promising candidate for intraoperative monitoring for patients with hemifacial spasm.