Work

Motor unit number index in Bell's palsy: A potential electrophysiological biomarker for early evaluation

Year: 2024

Type: article

Abstract: INTRODUCTION: Reliable, noninvasive early diagnostics of neuromuscular function in Bell's palsy, which causes facial paralysis and reduced quality of life, remain to be established. Here, we aimed to evaluate the utility of the motor unit number index (MUNIX) for the quantitative electrophysiological assessment of early-stage Bell's palsy, its correlation with clinical assessments, changes following treatment, and association with clinical prognosis. METHODS: MUNIX measures were recorded from the bilateral zygomaticus, orbicularis oculi, and orbicularis oris muscles of 10 healthy individuals and 64 patients with Bell's palsy. The patients were assessed by two specialist neurologists using the House-Brackmann and Sunnybrook Facial Grading Systems. Repeat assessments were performed on 20 patients with Bell's palsy who received treatment. Additionally, the 64 patients were reassessed using clinical scales after a 1-month interval. RESULTS: The MUNIX values of the main affected muscles on the affected side were lower than those on the healthy side in patients with Bell's palsy (p < .05). The MUNIX measurements significantly correlated with the clinical facial nerve palsy scale scores (p < .05). Significant improvements were observed in the MUNIX values on repeat testing following treatment (p < .05). The baseline motor unit size index (the compound muscle action potential amplitude divided by MUNIX) was positively associated with improved clinical presentation after 1 month (p < .05). CONCLUSION: MUNIX can be used as an electrophysiological biomarker for the quantitative assessment of facial nerve palsy and treatment response, and as a prognostic biomarker, in patients with early Bell's palsy, and is recommended as a complement to conventional neurophysiological examinations.

Source: Brain and Behavior

DOI: 10.1002/brb3.3632

Authors: Mengjie Chen, Mingxia Zhu, Xiuli Li, Jingtao Pi, Xinhong Feng

Institutions: Tongji University, Shanghai Sunshine Rehabilitation Center, Beijing Tsinghua Chang Gung Hospital, Tsinghua University

Language: English

Topic: Facial Nerve Paralysis Treatment and Research

Subfield: Neurology

Field: Medicine

Domain: Health Sciences

SDG: Good health and well-being

Open Access status: gold

Estimated APC paid: $3,460