van Wermeskerken Gijs K A, van Olphen Adriaan F, Smoorenburg Guido F
Department of Otorhinolaryngology, University Medical Center Utrecht, The Netherlands.
Int J Audiol. 2006 Sep;45(9):537-44. doi: 10.1080/14992020600825466.
The objective of this study was to investigate electrode impedance in cochlear implant recipients in relation to electrically evoked stapedius reflex measurements during surgery, and to electrode design, stimulation mode, and T and C levels over a nine month period after surgery. Seventy-five implant recipients, implanted with a Nucleus straight electrode array or a Contour array, were included. The results show that: (1) during surgery electrode impedance decreases markedly after electrically evoked stapedius reflex measurements, (2) after surgery, during the period without stimulation until speech processor switch-on, impedance increases, (3) after processor switch-on impedance decreases. The lower impedance values after a period of stimulation are found at the higher T and C levels. Impedances of the straight array electrodes are lower than those of the Contour array. The difference corresponds mainly to their respective surface areas. In addition, the straight array shows a larger increase of impedance in the apical direction than the Contour array, probably because of the larger fluid environment around the basal electrodes of the straight array.
本研究的目的是调查人工耳蜗植入者的电极阻抗，该阻抗与手术期间电诱发镫骨肌反射测量结果相关，并与术后九个月内的电极设计、刺激模式以及T和C水平相关。研究纳入了75名接受人工耳蜗植入的患者，他们植入的是Nucleus直电极阵列或Contour阵列。结果显示：（1）手术期间，在电诱发镫骨肌反射测量后电极阻抗显著降低；（2）术后，在无刺激直至言语处理器开启的期间，阻抗增加；（3）言语处理器开启后阻抗降低。在较高的T和C水平下，经过一段时间刺激后会发现较低的阻抗值。直阵列电极的阻抗低于Contour阵列电极的阻抗。这种差异主要与其各自的表面积有关。此外，直阵列在顶端方向的阻抗增加幅度大于Contour阵列，这可能是因为直阵列基底电极周围的液体环境更大。
