A novel electroneurography method in facial palsy

Abstract

Conclusion: The novel midline electroneurography (ENoG) method may have advantages over the standard method in terms of ease of electrode setting, and the ENoG value may be a useful prognostic factor. Objective: We compared ENoG performed in patients with facial palsy using two different methods – the new midline method and standard method – in terms of the amplitudes of the compound muscle action potentials (CMAPs) and relationship between the ENoG value and clinical course. Methods: A total of 64 patients with facial palsy were enrolled. CMAPs were recorded using the midline method, in which the recording electrodes were placed on the mental protuberance and philtrum over the orbicularis oris muscle, and the standard method, in which the recording electrodes were set close to the nasolabial fold. Percutaneous electrical stimulation was applied to the main trunk of the facial nerve. The amplitudes of the CMAPs and the relationship between the ENoG value and the period to full recovery from the facial palsy were compared. Results: The midline method had larger CMAP amplitudes on both sides and a stronger negative correlation in the relationship between the ENoG value and period to full recovery from palsy than the standard method statistically.

Keywords::

• Facial palsy
• electroneurography (ENoG)
• compound muscle action potential (CMAPS)
• orbicularis oris muscle

Acknowledgments

The authors thank Yasuichiro Nishimura PhD, Professor at the Department of Mathematics, Osaka Medical College, for helpful suggestions regarding the statistical analysis.

Declaration of interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.