Guinand N, van de Berg R, Ranieri M, Cavuscens S, DiGiovanna J, Nguyen T A K, Micera S, Stokroos R, Kingma H, Guyot J P, Perez Fornos A
Annu Int Conf IEEE Eng Med Biol Soc. 2015;2015:7192-5. doi: 10.1109/EMBC.2015.7320051.
The vestibular system plays an essential role in crucial tasks such as postural control, gaze stabilization, and spatial orientation. Currently, there is no effective treatment for a bilateral loss of the vestibular function (BVL). The quality of life of affected patients is significantly impaired. During the last decade, our group has explored the potential of using electrical stimulation to artificially restore the vestibular function. Our vestibular implant prototype consists of a custom modified cochlear implant featuring one to three vestibular electrodes implanted in the proximity of the ampullary branches of the vestibular nerve; in addition to the main cochlear array. Special surgical techniques for safe implantation of these devices have been developed. In addition, we have developed stimulation strategies to generate bidirectional eye movements as well as the necessary interfaces to capture the signal from a motion sensor (e.g., gyroscope) and use it to modulate the stimulation signals delivered to the vestibular nerves. To date, 24 vestibular electrodes have been implanted in 11 BVL patients. Using a virtual motion profile to modulate the "baseline" electrical stimulation, vestibular responses could be evoked with 21 electrodes. Eye movements with mean peak eye velocities of 32°/s and predominantly in the plane of the stimulated canal were successfully generated. These are within the range of normal compensatory eye movements during walking and were large enough to have a significant effect on the patients' visual acuity. These results indicate that electrical stimulation of the vestibular nerve has a significant functional impact; eye movements generated this way could be sufficient to restore gaze stabilization during essential everyday tasks such as walking. The innovative concept of the vestibular implant has the potential to restore the vestibular function and have a central role in improving the quality of life of BVL patients in the near future.
前庭系统在诸如姿势控制、注视稳定和空间定向等关键任务中发挥着重要作用。目前，对于双侧前庭功能丧失（BVL）尚无有效的治疗方法。受影响患者的生活质量受到显著损害。在过去十年中，我们团队探索了利用电刺激人工恢复前庭功能的潜力。我们的前庭植入物原型由定制改良的耳蜗植入物组成，其具有一到三个植入在前庭神经壶腹支附近的前庭电极，此外还有主要的耳蜗阵列。已经开发出了安全植入这些装置的特殊手术技术。此外，我们还开发了刺激策略以产生双向眼动，以及必要的接口来采集来自运动传感器（如陀螺仪）的信号，并利用该信号调节传递到前庭神经的刺激信号。迄今为止，已在11例BVL患者中植入了24个前庭电极。利用虚拟运动轮廓来调制“基线”电刺激，21个电极能够诱发前庭反应。成功产生了平均峰值眼速为32°/秒且主要在受刺激半规管平面内的眼动。这些眼动在行走过程中正常代偿性眼动的范围内，并且幅度足够大，对患者的视力有显著影响。这些结果表明，前庭神经的电刺激具有显著的功能影响；以这种方式产生的眼动可能足以在诸如行走等日常基本任务中恢复注视稳定。前庭植入物的创新概念有可能恢复前庭功能，并在不久的将来对改善BVL患者的生活质量发挥核心作用。
