IN SITU ANALYSIS OF INTRACOCHLEAR ELECTRODE POSITION

该子项目是利用NIH/NCRR资助的中心赠款提供的资源的许多研究子项目之一。子项目和研究者（PI）可能从另一个NIH来源获得主要资金，因此可以在其他CRISP条目中表示。所列机构为中心，不一定是研究者所在机构。耳蜗植入物现在被认为是一种有效的临床策略，以加强沟通，在深刻的听力受损。据估计，迄今为止，全世界已有超过15万名患者接受了植入手术。然而，这种方法的有效性在患者之间差异很大。动物行为研究同样表明，植入物性能的心理物理测量结果存在显著的受试者间差异。许多因素已被假设在这种变化中发挥作用。这些因素包括但不限于电极设计和配置、神经存活的总体变化、相对于电极触点的神经密度的局部变化、刺激触点的脑内位置以及电极触点和目标神经元件之间的距离的变化。 我们研究计划的目标是系统地研究耳蜗内电极位置与植入性能测量之间的关系。我们已根据我们的NIH-R 01在我们的长期（6年以上）、行为训练和植入动物中进行了广泛的长期行为和电生理测试。（NIH要求我们重新竞争UF的资助，目前正在准备竞争性的更新申请）。 为了确定耳蜗内每个电极触点的精确位置，需要结合多种技术; MRM用于关键解剖细节，TACT用于精细电极细节。目前，我们正在与Richard Webber博士（Bowman Gray医学中心; TACT的开发者）和Madhu Nair博士（佛罗里达大学; TACT应用的主要权威）合作，以优化TACT成像参数，从而在体内和动物处死后原位对阵列进行成像。虽然TACT可以提供植入电极阵列的最高分辨率图像，但它不能对内耳的精细骨结构和组织进行成像。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Cochlear implants are now seen as an effective clinical strategy for enhancing communication in the profoundly hearing impaired. Estimates suggest that over 150,000 patients worldwide have been implanted to date. The efficacy of this approach is, however, highly variable across patients. Animal behavioral studies have likewise shown significant inter-subject variability in psychophysical measures of implant performance. Numerous factors have been hypothesized to play roles in this variability. These factors include, but are not limited to, electrode design and configuration, overall variations in neural survival, local variations in neural density relative to electrode contacts, intracochlear location of stimulating contacts and variations in the distance between electrode contacts and the target neural elements. The goal of our reseach program has been to study systematically the relationship between electrode position within the cochlea and measures of implant performance. We have carried out extensive, long-term behavioral and electrophysiological testing in our long-term (6+ years), behaviorally-trained and implanted animals under our NIH-R01.( NIH asked us to recompete the grant from UF and a competing renewal application is currently being prepared). To determine the precise location of each electrode contact within the cochlea requires a combination of techniques; MRM for the critical anatomical details and TACT for the fine electrode details. At present we are working with Dr. Richard Webber (Bowman Gray Medical Center; developer of TACT) and Dr. Madhu Nair (University of Florida; a leading authority on TACT applications) to optimize TACT imaging parameters to image the arrays in vivo and, in situ after the animals have been sacrificed. While TACT can provide the highest resolution images of the implanted electrode array, it is not capable of imaging the fine bony structures and tissues of the inner ear.