Kaneko Mami, Sugiyama Yoichiro, Fuse Shinya, Mukudai Shigeyuki, Hirano Shigeru
Department of Otolaryngology-Head and Neck Surgery, Kyoto Prefectural University of Medicine, Kyoto, Japan.
Department of Otolaryngology-Head and Neck Surgery, Kyoto Prefectural University of Medicine, Kyoto, Japan.
J Voice. 2025 Jul;39(4):882-889. doi: 10.1016/j.jvoice.2022.12.023. Epub 2023 Jan 16.
Functional dysphonia (FD) varies in terms of vocal behavior and treatment efficacy. So-called hypofunctional dysphonia is characterized by insufficient subglottal pressure which causes a lack of driving power needed to vibrate the vocal folds leading to weak voice or aphonia in severe cases. While voice therapy is the initial treatment, some patients fail to respond to it. Interferential current (IFC) stimulation has been used as part of rehabilitation by physical therapists to reduce the progressive pain. IFC stimulation has also been developed as a laryngeal sensory stimulation device to modify the swallowing function by triggering swallowing reflex. Many researchers have shown recently in animal studies that laryngeal afferent inputs, such as vocal fold vibrations, subglottic pressure, flow rate, and vocal fold location affect vocal motor pattern and voice quality. However, IFC stimulation as a laryngeal afferent has not been verified. Herein, we assessed the effects of IFC stimulation to the neck on difficult functional dysphonia.
Six patients with refractory FD with insufficient subglottic pressure were assessed in this study. All six cases were females and two of them presented with aphonia. All cases were initially treated by voice therapy (VTx) such as flow phonation, water resistance therapy, or tube phonation for 2 months to increase subglottic pressure; however, this resulted in poor improvement in voice. We additionally performed VTx with concurrent application of IFC stimulation to the neck for 3 months, and the effects on voice were evaluated.
VTx with IFC stimulation resulted in improved voice in all cases, demonstrating the improvement in maximum phonation time, subglottic pressure, and voice handicap index-10.
Results from this clinical study suggest that VTx with IFC stimulation may be useful for adjusting vocal function in patients with FD caused by insufficient subglottic pressure.
功能性发声障碍（FD）在发声行为和治疗效果方面存在差异。所谓的发声功能减退性发声障碍的特征是声门下压力不足，这会导致缺乏振动声带所需的驱动力，严重时会导致声音微弱或失声。虽然嗓音治疗是初始治疗方法，但一些患者对此无反应。干扰电流（IFC）刺激已被物理治疗师用作康复治疗的一部分以减轻进行性疼痛。IFC刺激也已被开发为一种喉部感觉刺激装置，通过触发吞咽反射来改善吞咽功能。最近许多研究人员在动物研究中表明，喉部传入输入，如声带振动、声门下压力、流速和声带位置，会影响发声运动模式和嗓音质量。然而，IFC刺激作为一种喉部传入刺激尚未得到证实。在此，我们评估了颈部IFC刺激对难治性功能性发声障碍的影响。
本研究评估了6名声门下压力不足的难治性FD患者。所有6例均为女性，其中2例表现为失声。所有病例最初均接受嗓音治疗（VTx），如气流发声、抗阻训练或吹管发声训练2个月，以增加声门下压力；然而，嗓音改善不佳。我们额外进行了VTx，并同时对颈部进行IFC刺激3个月，然后评估对嗓音的影响。
IFC刺激联合VTx使所有病例的嗓音均得到改善，最大发声时间、声门下压力和嗓音障碍指数-10均有所改善。
这项临床研究结果表明，IFC刺激联合VTx可能有助于调节因声门下压力不足导致的FD患者的发声功能。
