Mechatronically guided micro navigation for soft tissue needle insertion

针的插入代表了一种有趣的替代微创和集中在软组织的诊断和治疗，例如，包括活组织检查或近距离治疗。然而，针头的插入通常会导致软组织变形，这可能导致针头相对于组织的错位。在第一个项目阶段，我们实现了一个机电一体化装置，以证明从针内进行高分辨率光学导航的可行性。利用集成在针头中的光纤组件，我们获得针头周围组织的高分辨率光学相干断层扫描图像。特别是，它可以检测到甚至很小的组织变形，并估计针和组织之间的相对运动。在第二个项目阶段，所得到的组织模型将扩展到包括弹性组织特性和更高分辨率的空间信息。一个目标是估计所需的信息，以模拟和预测从针内部针与组织的相互作用。与机电针驱动相结合，这将形成精确控制组织变形的针运动的基础。另一个方面是不同组织的可能分化。例如，组织的弹性特性也与组织的类型有关，例如，肿瘤组织通常弹性较小。为了考虑组织的结构差异，我们将首先将光学相干显微镜集成到针探针中。长期目标是使用形态学和力学组织模型定位和治疗计划。

The insertion of needles represents an interesting alternative for minimally invasive and focusses diagnosis and therapy in soft tissues, e.g., including biopsies or brachytherapy. However, needle insertion often causes substantial soft tissue deformation, which can result in a misplacement of the needle relative to the tissue. In a first project phase, we realized a mechatronic setup to prove feasibility of high resolution optical navigation from within the needle. Using fiber optic components integrated into the needle, we obtain high resolution optical coherence tomography images of the tissue surrounding the needle. Particularly, it is possible to detect even small deformations of the tissue and to estimate the relative motion between needle and tissue. In a second project phase the resulting tissue model will be extended to include elastic tissue properties and even higher resolution spatial information. One objective is to estimate the information needed to model and predict the needle-tissue interaction from within the needle. In combination with the mechatronic needle driving, this will form the basis for a precise control of the needle motion accounting for tissue deformation. Another aspect regards the possible differentiation of different tissues. For example, the elastic tissue properties are also related to the type of tissue, e.g., tumor tissue is often less elastic. To also consider structural differences in the tissue, we will first integrate optical coherence microscopy into a needle probe. A longer term objective is using the morphological and mechanic tissue model for localization and treatment planning.