Research Group Experimental Oto-Rhino-Laryngology, Department of Neurosciences, KU Leuven, University of Leuven, Leuven, Belgium; Leuven Brain Institute, Department of Neurosciences, KU Leuven, 3000 Leuven, Belgium.
OMFS IMPATH Research Group, Department of Imaging and Pathology, KU Leuven, University of Leuven, Leuven, Belgium; Department of Oral and Maxillofacial Surgery, UZ Leuven, University Hospitals Leuven, Leuven, Belgium.
Hear Res. 2023 Mar 15;430:108707. doi: 10.1016/j.heares.2023.108707. Epub 2023 Jan 25.
The risk of insertion trauma in cochlear implantation is determined by the interplay between individual cochlear anatomy and electrode insertion mechanics. Whereas patient anatomy cannot be changed, new surgical techniques, devices for cochlear monitoring, drugs, and electrode array designs are continuously being developed and tested, to optimize the insertion mechanics and prevent trauma. Preclinical testing of these developments is a crucial step in feasibility testing and optimization for clinical application. Human cadaveric specimens allow for the best simulation of an intraoperative setting. However, their availability is limited and it is not possible to conduct repeated, controlled experiments on the same sample. A variety of artificial cochlear models have been developed for electrode insertion studies, but none of them were both anatomically and mechanically representative for surgical insertion into an individual cochlea. In this study, we developed anatomically representative models of the scala tympani for surgical insertion through the round window, based on microCT images of individual human cochleae. The models were produced in transparent material using commonly-available 3D printing technology at a desired scale. The anatomical and mechanical accuracy of the produced models was validated by comparison with human cadaveric cochleae. Mechanical evaluation was performed by recording insertion forces, counting the number of inserted electrodes and grading tactile feedback during manual insertion of a straight electrode by experienced cochlear implant surgeons. Our results demonstrated that the developed models were highly representative for the anatomy of the original cochleae and for the insertion mechanics in human cadaveric cochleae. The individual anatomy of the produced models had a significant impact on the insertion mechanics. The described models have a promising potential to accelerate preclinical development and testing of atraumatic insertion techniques, reducing the need for human cadaveric material. In addition, realistic models of the cochlea can be used for surgical training and preoperative planning of patient-tailored cochlear implantation surgery.
人工耳蜗植入术中的插入性创伤风险取决于个体耳蜗解剖结构与电极插入力学之间的相互作用。虽然患者的解剖结构无法改变，但新的外科技术、耳蜗监测设备、药物和电极阵列设计不断被开发和测试，以优化插入力学并防止创伤。这些进展的临床前测试是可行性测试和优化的关键步骤。人体尸体标本允许对手术环境进行最佳模拟。然而，其可用性有限，并且不可能对同一样本进行重复、受控的实验。已经开发了各种人工耳蜗模型用于电极插入研究，但它们都没有在解剖学和机械方面代表对个体耳蜗的手术插入。在这项研究中，我们基于个体人耳蜗的 microCT 图像，为经圆窗的手术插入开发了具有解剖代表性的鼓阶模型。使用常见的 3D 打印技术，以所需的比例，在透明材料中生产模型。通过与人体尸体耳蜗进行比较，验证了所生产模型的解剖学和机械准确性。通过经验丰富的人工耳蜗植入外科医生手动插入直电极时记录插入力、计数插入电极的数量以及对触觉反馈进行分级，对机械性能进行评估。我们的结果表明，所开发的模型非常代表原始耳蜗的解剖结构和人尸体耳蜗中的插入力学。所生产模型的个体解剖结构对插入力学有重大影响。所描述的模型具有加速无创伤插入技术的临床前开发和测试的巨大潜力，减少了对人体尸体材料的需求。此外，耳蜗的逼真模型可用于手术培训和患者定制的耳蜗植入手术的术前规划。
