Greenberg A B, Myers M W, Hartshorn D O, Miller J M, Altschuler R A
University of Michigan, Kresge Hearing Research Institute, Ann Arbor 48109-0506.
Hear Res. 1992 Aug;61(1-2):19-23. doi: 10.1016/0378-5955(92)90031-h.
Cochlear implants are being applied to an ever widening patient population, including children in whom lifetime use of these devices is anticipated. Replacement of implants can be expected for reasons of device failure as well as future upgrading. This investigation was undertaken to examine the effect of cochlear electrode explanation and reimplantation on spiral ganglion cell survival. Guinea pigs with normal ears were initially implanted and either explanted or explanted and reimplanted (at 2 months) with a single wire ball-tip intracochlear electrode or a silastic carrier (each remaining for an additional 2 months). Little loss of hair cells or auditory nerve was observed across experimental groups and normal controls. Restricted basal turn cochlear and spiral ganglion cell loss was observed in a few animals in each group and was likely associated with mechanical damage from initial implantation. Likewise the scattered organ of Corti damage and hair cell loss observed was noted in only a few cochleae in each experimental group. Therefore, no significant differences in the average pathology across experimental groups and controls were observed. Thus, explantation or explantation with subsequent reimplantation does not appear to constitute an additional significant pathological risk compared to implantation alone.
人工耳蜗正应用于越来越广泛的患者群体，包括预期将终身使用这些设备的儿童。由于设备故障以及未来升级的原因，预计需要更换植入物。本研究旨在探讨人工耳蜗电极取出及重新植入对螺旋神经节细胞存活的影响。最初对听力正常的豚鼠进行植入，然后将其植入物取出，或者取出后（2个月时）再重新植入单丝球尖型人工耳蜗电极或硅橡胶载体（每种情况再持续2个月）。在各实验组和正常对照组中，未观察到毛细胞或听神经的大量损失。在每组的少数动物中观察到蜗底局限的耳蜗和螺旋神经节细胞损失，这可能与初次植入时的机械损伤有关。同样，在每个实验组中，仅在少数耳蜗中观察到散在的柯蒂器损伤和毛细胞损失。因此，在实验组和对照组之间未观察到平均病理学上的显著差异。因此，与单纯植入相比，取出植入物或取出后再重新植入似乎不会构成额外的显著病理风险。
