Roland J T, Magardino T M, Go J T, Hillman D E
Department of Otolaryngology, New York University Medical Center, New York, USA.
Ann Otol Rhinol Laryngol Suppl. 1995 Sep;166:64-8.
A cochlear lubricant may facilitate the surgeon's ability to place the electrode array deep within the cochlea. Patient performance with the multichannel cochlear implant may be enhanced with a deeper electrode insertion. Theoretically, deeper insertion and stimulation will recruit and activate more surviving spiral ganglion neurons. Several studies have shown that neuron survival is a factor for cochlear implant success, especially in the postmeningitis patient. We studied the histologic and electrophysiologic effects of the intracochlear injection of three potential lubricants in the guinea pig: glycerin, hyaluronic acid, and hydroxypropyl methylcellulose. All three have approved medical uses, reduce friction, and are readily available. Results show that when compared to surgical controls (cochleostomy without injection), there is no significant reduction in the spiral ganglion neuronal count at 2 and 8 weeks postinjection, and the dendrite and axon histology is well preserved. Injection of any of the substances within the cochlea causes severe hearing loss (detected by direct round window electrocochleographic responses to auditory stimuli) that only partially recovers with time. These findings suggest that any of the three tested substances could be considered as lubricants for intracochlear electrode insertion.
一种耳蜗润滑剂可能有助于外科医生将电极阵列深入植入耳蜗。更深的电极插入可能会提高多通道人工耳蜗植入患者的表现。从理论上讲，更深的插入和刺激将募集并激活更多存活的螺旋神经节神经元。多项研究表明，神经元存活是人工耳蜗植入成功的一个因素，尤其是在患过脑膜炎的患者中。我们研究了豚鼠耳蜗内注射三种潜在润滑剂（甘油、透明质酸和羟丙基甲基纤维素）的组织学和电生理效应。这三种物质均有批准的医疗用途，能减少摩擦且容易获得。结果显示，与手术对照组（未注射的蜗窗造口术）相比，注射后2周和8周时螺旋神经节神经元数量没有显著减少，且树突和轴突的组织学结构保存良好。在耳蜗内注射任何一种物质都会导致严重的听力损失（通过对听觉刺激的直接圆窗电耳蜗图反应检测到），且听力仅会随着时间部分恢复。这些发现表明，所测试的三种物质中的任何一种都可被视为耳蜗内电极插入的润滑剂。
