Fiber Bragg Grating based needle shape sensing for needle steering system: Evaluation in inhomogeneous tissue

Abstract

© 2017 IEEE. Despite many successful studies so far, flexible bevel-tipped needle steering still has many practical issues yet to be solved. One of them is the consideration of needle insertion into real tissue. One notable feature of real tissue lies in its in homogeneity. Hence the investigation of flexible needle insertion into inhomogeneous tissue is necessary. In this work, we examine the flexible needle insertion into three-layered phantom tissue. In particular, needle shape determination is executed by the method that was proposed previously, which combines a novel model that treats the needle as an inextensible elastic rod and curvature measurement through fiber Bragg grating (FBG) sensors embedded in the needle. Experiments on needle insertion into three-layered tissue are performed, then we evaluate the method. The results emphasize the effectiveness of the model and importance of initial angle in the needle insertion into tissues of different material properties.