Dynamic intracochlear pressure measurement during cochlear implant electrode insertion

Abstract

Background: Electrode insertion into the cochlea can cause significant pressure changes inside the cochlea with assumed effects on the cochlea’s functionality regarding residual hearing. Model-based intracochlear pressure (ICP) changes were performed statically at the cochlear helix.

Aims/objectives: The aim of this study was to observe dynamic pressure measurements during electrode insertion directly at the cochlear implant electrode.

Material and methods: The experiments were performed in an uncurled cochlear model that contained a volume value equivalent to a full cochlea. A microfibre pressure sensor was attached at one of two positions on a cochlear implant electrode and inserted under different insertional conditions.

Results: We observed the ICP increase depending on the insertional depth. A sensor-position-specific pressure change is insertional-depth dependent. Interval insertion did not lead to a lower peak insertional ICP.

Conclusions and significance: In contrast to the static pressure-sensor measurement in the artificial model’s helix, a dynamic measurement directly at the electrode shows the pressure profile to increase based on the insertional depth. A mechanical traumatic relevance of the observed pressure values cannot be fully excluded.

Chinese abstract

背景：电极插入耳蜗可引起耳蜗内压力的显著变化, 并对残余听力方面的耳蜗功能产生了所设想的影响。在耳蜗螺旋线处静态进行基于模型的耳蜗内压（ICP）变化。

目的：本研究的目的是观察电极直接插入耳蜗植入电极时的动态压力测数。

材料和方法：实验是在一个未弯曲的耳蜗模型中进行的, 该模型的体积与全耳蜗的相当。将微纤维压力传感器安装在人工耳蜗植入电极的两个位置之一, 并在不同的插入条件下插入。

结果：随着插入深度的增加, 耳蜗内压升高。传感器位置特定的压力变化取决于插入深度。间隔插入并没有导致较低的峰值插入ICP。

结论与意义：与人工模型螺旋线中的静态压力传感器测量相反, 直接在电极上进行的动态测量显示, 根据插入深度, 压力会增加。不能完全排除所观察到的压力值可能与机械创伤相关。

Keywords:

• Intracochlear pressure
• cochlear implant
• electrode insertion

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This study was supported by Advanced Bionics, Stäfa, Switzerland.