Section of Otolaryngology-Head and Neck Surgery, Department of Surgery, University of Chicago, Chicago, Illinois 60637-1447, USA.
Laryngoscope. 2011 Dec;121(12):2641-8. doi: 10.1002/lary.22383.
OBJECTIVES/HYPOTHESIS: The aim of this study was to analyze the cochlear nucleus neuron population in individuals with normal hearing and presbycusis.
Retrospective study of archival human temporal bone and brain stem tissues.
Using strict inclusion criteria, the temporal bones and cochlear nuclei from six normal hearing individuals and four individuals with presbycusis were selected for analysis. The spiral ganglion cell population, the cochlear nucleus neuron population, and the cell body size of the neurons were quantified in these cases.
A relationship was not observed between age and the spiral ganglion cell population in the normal hearing group. Presbycusis subjects exhibited a reduced spiral ganglion cell population. The mean cochlear nucleus neuron population was observed to be significantly higher in the presbycusis group (mean ± standard deviation: 114,170 ± 10,570) compared to the normal hearing group (91,470 ± 9,510) (P = .019). This difference was predominantly the result of greater multipolar and granule cell neuron populations. Only the fusiform neuron type exhibited a significantly different mean cell body cross-sectional area between the normal hearing group (242 ± 27) and the presbycusis group (300 ± 37) (P = .033).
This investigation is the first time, to our knowledge, that the populations of the eight neuron types in the cochlear nucleus have been quantified in both normal hearing individuals and individuals with presbycusis. The data support the concept that presbycusis is not an effect of aging alone but instead may be a condition that predisposes one to hearing loss with advancing age and is characterized by a congenitally elevated cochlear nucleus neuron population.
目的/假设：本研究旨在分析正常听力和老年性聋个体的耳蜗核神经元群体。
对存档的人颞骨和脑干组织进行回顾性研究。
使用严格的纳入标准，选择了 6 名正常听力个体和 4 名老年性聋个体的颞骨和耳蜗核进行分析。对这些病例的螺旋神经节细胞群体、耳蜗核神经元群体和神经元胞体大小进行了量化。
在正常听力组中，年龄与螺旋神经节细胞群体之间未观察到相关性。老年性聋患者的螺旋神经节细胞群体减少。老年性聋组的平均耳蜗核神经元群体（均值±标准差：114170±10570）明显高于正常听力组（91470±9510）（P=0.019）。这种差异主要是由于多极和颗粒细胞神经元群体的增加。只有梭形神经元类型的平均胞体横截面积在正常听力组（242±27）和老年性聋组（300±37）之间存在显著差异（P=0.033）。
据我们所知，这是首次对正常听力个体和老年性聋个体的耳蜗核 8 种神经元类型的群体进行量化研究。这些数据支持这样一种观点，即老年性聋不仅仅是衰老的影响，而是一种可能导致随着年龄增长听力损失的状况，其特征是耳蜗核神经元群体先天升高。
