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Updated: Jun 19, 2026
Microvascular Decompression: Salient Surgical Principles and Technical Nuances
Published on: July 5, 2011
Utility of intraoperative electromyography in microvascular decompression for hemifacial spasm: a meta-analysis
Raymond F Sekula1, Sanjay Bhatia, Andrew M Frederickson
1Center for Cranial Nerve Disorders, Department of Neurosurgery, Allegheny General Hospital, Allegheny Neuroscience Institute/Drexel University College of Medicine, Pittsburgh, Pennsylvania 15212, USA. rsekula@wpahs.org
Object:
In this paper, the authors' goal was to determine the utility of monitoring the abnormal muscle response (AMR) or "lateral spread" during microvascular decompression surgery for hemifacial spasm.
Methods:
The authors' experience with AMR as well as the data available in the English-language literature regarding resolution or persistence of AMR and the resolution or persistence of hemifacial spasm at follow-up was pooled and subjected to a meta-analysis.
Results:
The pooled OR revealed by the meta-analysis was 4.2 (95% CI 2.7-6.7). The chance of a cure if the AMR was abolished during surgery was 4.2 times greater than if the lateral spread persisted.
Conclusions:
The AMR should be monitored routinely in the operating room, and surgical decision-making in the operating room should be augmented by the AMR.