Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, New York, United States of America.
PLoS One. 2011;6(8):e24258. doi: 10.1371/journal.pone.0024258. Epub 2011 Aug 31.
Bilateral vocal fold paralysis (BVCP) is a life threatening condition and appears to be a good candidate for therapy using functional electrical stimulation (FES). Developing a working FES system has been technically difficult due to the inaccessible location and small size of the sole arytenoid abductor, the posterior cricoarytenoid (PCA) muscle. A naturally-occurring disease in horses shares many functional and etiological features with BVCP. In this study, the feasibility of FES for equine vocal fold paralysis was explored by testing arytenoid abduction evoked by electrical stimulation of the PCA muscle. Rheobase and chronaxie were determined for innervated PCA muscle. We then tested the hypothesis that direct muscle stimulation can maintain airway patency during strenuous exercise in horses with induced transient conduction block of the laryngeal motor nerve. Six adult horses were instrumented with a single bipolar intra-muscular electrode in the left PCA muscle. Rheobase and chronaxie were within the normal range for innervated muscle at 0.55±0.38 v and 0.38±0.19 ms respectively. Intramuscular stimulation of the PCA muscle significantly improved arytenoid abduction at all levels of exercise intensity and there was no significant difference between the level of abduction achieved with stimulation and control values under moderate loads. The equine larynx may provide a useful model for the study of bilateral fold paralysis.
双侧声带麻痹 (BVCP) 是一种危及生命的疾病，似乎是使用功能性电刺激 (FES) 治疗的良好候选者。由于唯一的杓状软骨外展肌、环杓后肌 (PCA) 肌肉的位置难以接近且体积较小，开发有效的 FES 系统在技术上具有挑战性。马中一种自然发生的疾病在功能和病因方面与 BVCP 有许多共同特征。在这项研究中，通过测试 PCA 肌肉电刺激引起的杓状软骨外展来探索 FES 治疗马声带麻痹的可行性。确定了受神经支配的 PCA 肌肉的电流强度和时值。然后，我们测试了以下假设：在诱导喉运动神经短暂传导阻滞的马剧烈运动期间，直接肌肉刺激可以维持气道通畅。六匹成年马在左侧 PCA 肌肉中植入了单个双极肌内电极。电流强度和时值分别为 0.55±0.38 v 和 0.38±0.19 ms，在受神经支配的肌肉的正常范围内。PCA 肌肉的肌内刺激显著改善了所有运动强度水平的杓状软骨外展，并且在中度负荷下刺激和对照值之间的外展水平没有显著差异。马的喉可能为双侧声带麻痹的研究提供有用的模型。
