IN SITU ANALYSIS OF INTRACOCHLEAR ELECTRODE POSITION

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 人工耳蜗植入物现在被视为一种有效的临床策略，可以加强严重听力障碍者的沟通。据估计，到目前为止，全球已有超过15万名患者被植入。然而，这种方法的疗效在不同患者之间存在很大差异。动物行为研究也同样表明，在植入性能的心理物理测量中，受试者之间存在显著的变异性。许多因素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、神经密度相对于电极接触的局部变化、刺激接触的耳壳内位置以及电极接触与目标神经元件之间距离的变化。 我们的研究计划的目标是系统地研究电极在耳蜗内的位置与种植体性能的测量之间的关系。我们已经在我们的NIH-R01下对长期(6年以上)、行为训练和植入的动物进行了广泛、长期的行为和电生理测试。(NIH要求我们重新竞争UF的拨款，目前正在准备竞争续签申请)。 要确定耳蜗内每个电极接触的准确位置，需要多种技术的结合；关键解剖细节的磁共振成像和精细电极细节的机智。目前，我们正在与Richard Webber博士(Bowman Gray Medical Center；TACT的开发商)和Madhu Nair博士(佛罗里达大学，TACT应用领域的领先权威)合作，优化TACT成像参数，以便在活体和动物牺牲后原位成像阵列。虽然Tact可以提供植入电极阵列的最高分辨率图像，但它无法成像内耳的细微骨骼结构和组织。

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.