Vestibular Rehabilitation and Otolith Dysfunction

 描述(由申请人提供)： 新的证据表明，前庭系统的耳石器官功能障碍发生在退伍军人中，他们的头晕和失衡与轻度创伤性脑损伤/冲击波暴露有关。目前尚不清楚标准的前庭康复对耳石功能障碍患者是否有效，该试点项目旨在检验前庭康复的有效性和一种新的治疗方法。前庭(内耳平衡)系统的主要功能是保持凝视和姿势的稳定。前庭系统由两种类型的感觉器官(半规管和耳石器官)组成，对平衡有独特的贡献。前庭功能丧失可发生在一个或多个前庭感觉器官。前庭缺失的症状包括头晕、姿势不稳和/或视觉模糊。此外，前庭功能丧失的个体比同龄健康个体跌倒的发生率更高(Herdman等人，2000年)。最近的研究表明，在有头部创伤/冲击波暴露和/或噪声性听力损失病史的人中，耳石功能障碍是相当常见的发现(Akin&Murnane，2011；Akin等人，2012)。因此，耳石功能障碍可能是退伍军人的一个重要健康问题，确定耳石功能障碍的最佳干预措施与退伍军人管理局的医疗保健相关。前庭康复(VR)是与前庭功能障碍相关的头晕、失衡和活动障碍患者的治疗选择。VR通常包括凝视稳定练习、步态和平衡训练以及一般条件训练。凝视稳定性练习基于适应和替代的概念，目的是促进半规管介导的角前庭-眼反射(AVOR)的前庭代偿。诱导适应的一个关键信号是头部运动过程中的视网膜滑动；因此，适应练习包括在聚焦于目标的同时旋转头部。对前庭功能障碍患者的研究表明，VR导致许多但不是所有患者的主观主诉减少和功能改善(Herdman等人，2012年)。许多可能影响恢复的因素，例如不同前庭感觉器官(半规管与耳石器官)的受累，尚未被检查以确定它们对恢复的影响。大多数检验VR有效性的研究只使用了VOR功能的测试(卡路里和旋转测试)，测量HSCC来确定前庭丢失。因此，对于促进前庭代偿的干预措施知之甚少。 耳石器官。最近的研究表明，使用离心法(或直线加速法)刺激耳石器官后的适应。使用离心机进行耳石适应的概念可能类似于使用凝视稳定性练习进行AVOR适应。在空间飞行期间接受离心机(即离轴旋转)的宇航员没有表现出典型的耳石-眼反射的解除条件(Buytaert等人，2013年)。在一个案例研究中，Akin等人。(2013)在对1例慢性单侧前庭功能减退患者进行离心术后，症状和平衡均有所改善。该项目的目的是确定离心法是否是治疗退伍军人慢性支气管炎的有效干预策略。 耳石功能障碍。具体目标1旨在确定标准前庭康复治疗耳石功能障碍的效果。与耳石功能障碍相关的头晕/失衡的退伍军人将被随机分阶段进行干预，包括4周的凝视稳定性练习，然后是4周的平衡和步态练习。通过提供阶段性干预，我们将能够分离出耳石功能障碍康复的关键组成部分。具体目标2旨在检查离心法对耳石功能障碍患者预后的影响程度。与耳石功能障碍相关的头晕/失衡的退伍军人将被随机分成4周的离心法(耳石器官刺激)和4周的平衡和步态练习的阶段性干预。对症状强度、平衡性和步态的结果进行比较。

 DESCRIPTION (provided by applicant): Emerging evidence suggests that otolith organ dysfunction of the vestibular system occurs in Veterans with dizziness and imbalance related to mild traumatic brain injury/blast exposure. It is unclear if standard vestibular rehabilitation is effective for individuals with otolith dysfunction This pilot project is designed to examine the effectiveness of vestibular rehabilitation and a novel treatment approach. The primary function of the vestibular (inner ear balance) system is to maintain gaze and postural stability. The vestibular system is comprised of two types of sensory organs (semicircular canals and otolith organs) with unique contributions to balance. Loss of vestibular function can occur in one or more vestibular sensory organs. Symptoms of vestibular loss include dizziness, postural instability, and/or visual blurring. Moreover, the incidence of falls is greater in individuals with vestibular loss than in healthy individuals of th same age (Herdman et al., 2000). Recent studies suggest that otolith dysfunction is a fairly common finding in individuals with a history of head trauma/blast exposure and/or noise induced hearing loss (Akin & Murnane, 2011; Akin et al., 2012). Therefore, otolith dysfunction may be a significant health concern for the Veteran population, and determining optimal intervention for otolith dysfunction is relevant to VA healthcare. Vestibular Rehabilitation (VR) is the treatment o choice for patients experiencing dizziness, imbalance, and mobility impairments related to vestibular dysfunction. VR typically includes gaze stability exercises, gait and balance training, and general conditioning. Gaze stability exercises are based on the concepts of adaptation and substitution with the goal of facilitating vestibular compensation of the semicircular canal-mediated angular vestibulo-ocular reflex (aVOR). A critical signal to induce adaptation is retinal slip during head movements; thus, adaptation exercises involve head rotation while focusing on a target. Studies of individuals with vestibular dysfunction suggest that VR results in decreased subjective complaints and improved function in many but not all patients (Herdman et al., 2012). Many factors that might influence recovery, such as the involvement of different vestibular sensory organs (semicircular canals versus otolith organs) have not been examined to determine their impact on recovery. Most studies examining the effectiveness of VR have used only tests of VOR function (caloric and rotational tests) that measure hSCC to determine vestibular loss. Thus, little is known about interventions to facilitate vestibular compensation of the otolith organs. Recent studies have demonstrated adaptation following otolith organ stimulation using centrifugation (or linear acceleration). The concept of using centrifugation for otolith adaptation may be similar to using gaze stability exercises for aVOR adaptation. Astronauts who received centrifugation (i.e., off-axis rotation) during in-space flight did not exhibit the typical deconditioning of the otolith-ocular reflex (Buytaert et al., 2013). In a case study, Akin et al. (2013) demonstrated improved symptoms and balance following centrifugation of a patient with chronic unilateral vestibular hypofunction. The purpose of this project is to determine if centrifugation is an effective intervention strategy in the treatment of Veterans with otolith dysfunction. Specific Aim 1 is designed to determine the effect of standard vestibular rehabilitation on otolith dysfunction. Veterans with dizziness/imbalance related to otolith dysfunction will be randomized to a staged intervention of 4 weeks of gaze stability exercises followed by 4 weeks of balance and gait exercises. By providing the intervention in a staged manner we will be able to isolate critical components of rehabilitation of otolith dysfunction. Specific Aim 2 is designed to examine the extent to which centrifugation impacts outcomes for individuals with otolith dysfunction. Veterans with dizziness/imbalance related to otolith dysfunction will be randomized to a staged intervention of 4 weeks of centrifugation (otolith organ stimulation) followed by 4 weeks of balance and gait exercises. Outcome measures of symptom intensity, balance, and gait will be compared.