Immediate effect of recurrent laryngeal nerve stimulation in patients with idiopathic unilateral vocal fold paralysis

Abstract

Background

There is a lack of effective treatment for idiopathic unilateral vocal fold paralysis (IUVFP). A better phonation was reported by patients after laryngeal nerve stimulation during our clinical examination.

Objectives

This study aims to investigate immediate effect of recurrent laryngeal nerve (RLN) stimulation on phonation in patients with IUVFP.

Material and Methods

Sixty-two patients with clinically identified IUVFP underwent RLN stimulation with needle electrodes. Laryngoscopy, acoustic analysis, and voice perception assessment were performed for quantitative comparison of vocal function and voice quality before and after the intervention.

Results

Laryngoscopic images showed a larger motion range of the paralyzed vocal fold (p < .01) and better glottal closure (p < .01) after RLN stimulation. Acoustic analysis revealed that the dysphonia severity index increased significantly (p < .01) while the jitter and shimmer decreased after the intervention (p < .05). According to perceptual evaluation, RLN stimulation significantly increased RBH grades in patients with IUVFP (p < .01). Furthermore, the improvement in voice perception had a moderate positive correlation with the decrease in the glottal closure.

Conclusions and Significance

This study shows a short-term improvement of phonation in IUVFP patients after RLN stimulation, which provides proof-of-concept for trialing a controlled delivery of RLN stimulation and assessing durability of any observed responses.

Chinese abstract

背景

特发性单侧声带麻痹(IUVFP)缺乏有效的治疗方法。据患者报告, 在我们的临床检查时, 喉神经刺激后发音更好。

目的

本研究旨在探讨返喉神经(RLN)刺激对IUVFP患者发音的即时效果。

材料和方法

62例临床确诊的IUVFP患者接受针状电极RLN刺激。进行喉镜检查、声学分析和声音感知评估, 对干预前后的发声功能和声音质量进行定量比较。

结果

喉镜图像显示, RLN刺激后麻痹声带的运动范围较大(p < 0.01), 声门闭合更好(p < 0.01)。声学分析显示, 干预后发音困难严重程度指数显著增加(p < 0.01), 而抖动和微光减少(p < 0.05)。根据感知评估, RLN刺激显著提高了IUVFP患者的RBH等级(p < 0.01)。此外, 声音感知的改善与声门闭合减少呈中度正相关。

结论和意义

本研究显示, IUVFP患者经RLN刺激后发音有短期改善, 这为试验RLN刺激的控制性递送和评估任何所观察到的反应的持久性提供了概念证明。

Keywords:

• Idiopathic unilateral vocal fold paralysis
• neuromuscular electrical stimulation
• recurrent laryngeal nerve
• vocal function
• voice quality

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by the National Natural Science Foundation of China [grant numbers 12274340, 62076198].