Khan Aayesha M, Handzel Ophir, Damian Doris, Eddington Donald K, Nadol Joseph B
Department of Otology and Laryngology, Harvard Medical School, Boston, Massachusetts, USA.
Ann Otol Rhinol Laryngol. 2005 May;114(5):381-5. doi: 10.1177/000348940511400508.
It is generally assumed that at least a minimal number of spiral ganglion cells is essential for successful speech perception with a cochlear implant. Although the insertion of a multichannel cochlear implant frequently results in loss of residual hearing in the implanted ear, this outcome does not imply that significant damage to residual populations of spiral ganglion cells has occurred. The purpose of the current study was to compare spiral ganglion cell counts in implanted and nonimplanted cochleas in 11 patients for whom both temporal bones were available and in whom a multichannel cochlear implant had been placed unilaterally. The temporal bones were processed for light microscopy by standard techniques. The cochleas were reconstructed by 2-dimensional methods. Spiral ganglion cell counts of the implanted and nonimplanted sides were compared by a paired t-test (2-tailed). The mean spiral ganglion cell counts for implanted and nonimplanted ears were not statistically different in the most basal three segments of the cochlea. However, the mean spiral ganglion cell count in segment 4 (apical segment) and the mean total spiral ganglion cell count were lower in the implanted cochleas than in the nonimplanted cochleas (p < .01). The results of this study suggest a modest decrease in the total spiral ganglion cell count in the implanted ears as compared to the nonimplanted ears, principally in the apical segment. Possible interpretations of this finding are discussed.
一般认为，对于人工耳蜗成功实现言语感知而言，至少需要一定数量的螺旋神经节细胞。尽管多通道人工耳蜗的植入常常会导致植入耳残余听力丧失，但这一结果并不意味着螺旋神经节细胞的残余群体已遭受显著损伤。本研究的目的是比较11例双侧颞骨均可用且单侧植入多通道人工耳蜗患者的植入侧和未植入侧耳蜗的螺旋神经节细胞数量。颞骨采用标准技术进行光镜处理。耳蜗通过二维方法重建。植入侧和未植入侧的螺旋神经节细胞数量通过配对t检验（双侧）进行比较。在耳蜗最基部的三个节段中，植入耳和未植入耳的平均螺旋神经节细胞数量无统计学差异。然而，植入侧耳蜗第4节段（顶端节段）的平均螺旋神经节细胞数量和螺旋神经节细胞总数均低于未植入侧耳蜗（p < 0.01）。本研究结果表明，与未植入耳相比，植入耳的螺旋神经节细胞总数略有减少，主要集中在顶端节段。文中讨论了这一发现的可能解释。
