Guyot Jean-Philippe, Sigrist Alain, Pelizzone Marco, Feigl Georg C, Kos Maria Izabel
Otorhinolaryngology-Head and Neck Surgery Service, Department of Clinical Neurosciences, Faculty of Medicine, University of Geneva, Switzerland.
Ann Otol Rhinol Laryngol. 2011 Feb;120(2):81-7. doi: 10.1177/000348941112000202.
Recently, we demonstrated that it was possible to elicit vertical eye movements in response to electrical stimulation of the posterior ampullary nerve. In order to develop a vestibular implant, a second site of stimulation is required to encode the horizontal movements.
Three patients with disabling Meniere's disease were included in the study. Before a labyrinthectomy via a standard transcanal approach was performed, their lateral and anterior ampullary nerves were surgically exposed under local anesthesia through a procedure we recently developed. The attic was opened, the incus and malleus head were removed, and a small well was drilled above the horizontal portion of the facial nerve canal to place an electrode. This electrode was used to deliver balanced biphasic trains of electrical pulses.
The electrical stimuli elicited mainly horizontal nystagmus without simultaneous stimulation of the facial nerve.
It is possible to stimulate electrically the lateral and superior ampullary nerves without simultaneous stimulation of the facial nerve. Because the nerves run close to each other, electrical stimulation provoked eye movements that were not purely horizontal, but also had some vertical components. Nevertheless, this site can be used to encode horizontal movements, because central adaptation may correct unnatural afferent vestibular cues delivered by a prosthetic sensor. The range of stimulus intensities that produced a response was broad enough for us to envision the possibility of encoding eye movements of various speeds.
最近，我们证明了通过电刺激后半规管神经能够诱发垂直眼动。为了开发前庭植入物，需要第二个刺激部位来编码水平运动。
三名重度梅尼埃病患者纳入本研究。在通过标准经耳道入路进行迷路切除术之前，通过我们最近开发的一种手术方法在局部麻醉下手术暴露他们的外侧和前半规管神经。打开上鼓室，切除砧骨和锤骨头，并在面神经管水平段上方钻一个小孔以放置电极。该电极用于传递平衡的双相电脉冲序列。
电刺激主要诱发水平眼震，而未同时刺激面神经。
可以在不同时刺激面神经的情况下电刺激外侧和上半规管神经。由于这些神经彼此靠近，电刺激引发的眼动并非纯粹水平的，还具有一些垂直成分。然而，该部位可用于编码水平运动，因为中枢适应可能会校正由假体传感器传递的不自然的前庭传入信号。产生反应的刺激强度范围足够宽，使我们能够设想编码各种速度眼动的可能性。
