Investigation of methods and materials for individually mouldable micro-stereotactic frame

在所有手术领域中，随着不断减少侵入性和不断提高的准确性要求的不断进步，通过辅助系统对外科医生的支持变得越来越不可或缺。然而，这些系统通常是大的和昂贵的（例如手术机器人）或不够准确（例如图像引导手术系统）。此外，这些干预措施中有相当一部分的特点是定位任务相对简单。为此目的，小型化立体定向框架可能是适当的。在这一跨学科的研究项目中，应开发一种可单独模制的仪器指南的新概念，并系统地评估其准确性和临床操作。总体目标是使手术人员能够在手术室中以完全无菌的过程直接构建定位辅助装置，具有直观且易于学习的手动步骤，以便立即用于特定患者。这样做的人应该能够在未来没有昂贵和复杂的辅助设备的情况下沿着。因此，在此项目中明确探索了简化的限制-同时牢记最高的精度要求。在项目开始时，合适的材料（建模化合物，粘合剂等）将在基础实验中选择并评价可实现的准确性、术中处理以及个体建模和硬化的时间。此外，设计和精度之间的因果关系将根据实验结果进行调查。在该项目的进一步过程中，这些一般见解将应用于新型微型立体定向框架的开发过程，重点是最大的准确性和最佳的简单性。在最后一系列实验中，首先使用人造颅骨模型，然后使用人颞骨样本，将在满足规定要求方面对系统进行计量学评价，并进行临床评级。这项基础研究和开发是使用微创人工耳蜗植入手术作为复杂手术任务的具体示例来进行的，以便回答以简单和低技术水平为特征的辅助系统是否适合于（选定的）高精度干预的问题。此外，这些发现可以得出结论，这种微立体定向框架适用于哪种类型的外科手术，以及哪些不可接受的安全限制简化。

The ongoing progress in all fields of surgery with continuously minimized invasiveness and with ever increasing accuracy requirements makes support of the surgeon through assistance systems increasingly indispensable. However, these systems are often large and expensive (such as surgical robots) or not sufficiently accurate (such as image-guided surgery systems). In addition, a relevant proportion of these interventions are characterized by a comparatively simple positioning task. For this purpose, miniaturized stereotactic frames could be appropriate. Within this interdisciplinary research project, a new concept for an individually mouldable instrument guide should be developed and evaluated systematically regarding accuracy and clinical handling. The overall objective is to enable the surgical staff to build the positioning aid directly in the operating room in a completely sterile process with intuitive and easy to learn manual steps for an immediately use for the particular patient. Doing so one should be able to get along without expensive and complex assistance devices in the future. Therefore, the limits of simplification are explored explicitly in this project – while keeping in mind highest accuracy requirements at the same time.At the beginning of the project suitable materials (modeling compounds, adhesives, etc.) will be selected and evaluated in basic experiments regarding achievable accuracy, intraoperative handling, and time for individual modeling and hardening. In addition, the causal linkage between design and accuracy will be investigated based on experimental results. In the further course of the project, these general insights are going to be applied for the development process of a novel micro-stereotactic frame with focus on maximum accuracy and the best possible simplicity. In final series of experiments, first using artificial skull phantoms, later human temporal bone specimens, the system will be metrologically evaluated in terms of fulfilling the stated requirements as well as rated clinically. This basic research and development is carried out using minimally invasive cochlear implantation surgery as a concrete example of a sophisticated surgical task in order to answer the question whether an assistance system characterized by simplicity and low level of technology is suitable for (selected) high-precision interventions. Additionally, these findings allow to conclude for which type of surgical interventions such micro-stereotactic frames are suitable – and for which unacceptable curtailments of safety limit simplification.