A New Sensor Technology for 2D Ultrasound-Guided Needle Tracking Huanxiang Lu 1 , Junbo Li 1 , Qiang Lu 2 , Shyam Bharat 3 , Ramon Erkamp 3 , Bin Chen 3 , Jeremy Drysdale 3 , Francois Vignon 3 , and Ameet Jain 3 1 Philips Research China, Shanghai, China 2 Ultrasound department, Huaxi hospital, Chengdu, China 3 Philips Research North America, New York, USA Abstract. 2D Ultrasound (US) is becoming the preferred modality for image-guided interventions due to its low cost and portability. However, the main limitation is the limited visibility of surgical tools. We present a new sensor technology that can easily be embedded on needles that are used for US-guided interventions. Two different types of materials are proposed to be used as sensor - co-polymer and PZT. The co-polymer technology is particularly attractive due to its plasticity, allowing very thin depositions (10-20 μm) on a variety of needle shapes. Both sensors receive acoustic energy and convert it to an electrical signal. The precise location of the needle can then be estimated from this signal, to provide real-time feedback to the clinician. We evaluated the feasibility of this new technology using (i) a 4DOF robot in a water tank; (ii) extensive ex vivo experiments; and (iii) in vivo studies. Quantitative robotic studies indicated that the co-polymer is more robust and stable when compared to PZT. In quantitative experiments, the technology achieved a tracking accuracy of 0.14 ± 0.03mm, significantly superior to competing technolo- gies. The technology also proved success in near-real clinical studies on tissue data. This sensor technology is non-disruptive of existing clinical workflows, highly accurate, and is cost-effective. Initial clinician feedback shows great potential for large scale clinical impact. 1 Introduction Over 20 million needle interventions are performed every year around the world. Although 2D US is an attractive imaging modality due to its portability and cost- effectiveness, it has not yet become the gold standard for interventions. This is due to the fact that interventional needles, which are specular reflectors, cannot be consistently displayed under US (See Fig. 1). Depending on the insonifying angles, the ultrasound signal does not always backscatter to the transducer, resulting in poor needle visibility. Additionally, the needle deviates from the imaging plane during the procedure, further decreasing the clinician confidence. Such limitations hinder the usability of 2D US for interventions. Various approaches have been proposed to tackle the “invisible tool” problem, which can generally be classified into two categories. The first category focuses P. Golland et al. (Eds.): MICCAI 2014, Part II, LNCS 8674, pp. 389–396, 2014. c  Springer International Publishing Switzerland 2014