IEEE Trans Biomed Eng. 2018 Mar;65(3):658-668. doi: 10.1109/TBME.2017.2700361. Epub 2017 Jun 5.
Electric stimulation of the auditory nerve by cochlear implants has been a successful clinical intervention to treat the sensory neural deafness. In this pathological condition of the cochlea, type-1 spiral ganglion neurons in Rosenthal's canal play a vital role in the action potential initiation. Various morphological studies of the human temporal bones suggest that the spiral ganglion neurons are surrounded by heterogeneous structures formed by a variety of cells and tissues. However, the existing simulation models have not considered the tissue heterogeneity in the Rosenthal's canal while studying the electric field interaction with spiral ganglion neurons. Unlike the existing models, we have implemented the tissue heterogeneity in the Rosenthal's canal using a computationally inexpensive image based method in a two-dimensional finite element model. Our simulation results suggest that the spatial heterogeneity of surrounding tissues influences the electric field distribution in the Rosenthal's canal, and thereby alters the transmembrane potential of the spiral ganglion neurons. In addition to the academic interest, these results are especially useful to understand how the latest tissue regeneration methods such as gene therapy and drug-induced resprouting of peripheral axons, which probably modify the density of the tissues in the Rosenthal's canal, affect the cochlear implant functionality.
电刺激听神经的耳蜗植入物已成为治疗感觉神经性耳聋的成功临床干预措施。在耳蜗的这种病理条件下，罗斯恩塔尔氏管中的 1 型螺旋神经节神经元在动作电位起始中起着至关重要的作用。对人颞骨的各种形态学研究表明，螺旋神经节神经元被由各种细胞和组织形成的异质结构所包围。然而，在研究与螺旋神经节神经元的电场相互作用时，现有的模拟模型并未考虑罗斯恩塔尔氏管中的组织异质性。与现有的模型不同，我们在二维有限元模型中使用计算成本低廉的基于图像的方法实现了罗斯恩塔尔氏管中的组织异质性。我们的模拟结果表明，周围组织的空间异质性会影响罗斯恩塔尔氏管中的电场分布，从而改变螺旋神经节神经元的跨膜电位。除了学术兴趣外，这些结果对于理解最新的组织再生方法（例如基因治疗和药物诱导的外周轴突再生）如何影响耳蜗植入物的功能尤其有用，因为这些方法可能会改变罗斯恩塔尔氏管中的组织密度。
