Development of multi-spot impedance sensing biopsy needle based on attachable and flexible sensor film

We demonstrate the biopsy needle capable of multi-spot impedance sensing based on attachable and flexible sensor film. In order to directly integrate sensor electrodes into curved surface of biopsy needle, attachable and thin polyimide substrate was used. Sensor electrodes were easily manipulated due to advantage of conventional microfabrication technique and this enable capability of multi-spot impedance sensing. To verify validity of proposed method, attachability of sensor film and real-time response of multi-spot sensing of fabricated biopsy needle was investigated.

I. Introduction

In order to make definitive diagnosis of diseases, histological assessment is essential because there is limitation of distinguishability only with medical imaging tools such as ultrasound, computed tomography and magnetic resonance imaging. Therefore, biopsy surgery to get suspicious lesions is necessary. In conventional biopsy process, biopsy needles are used and tissue right ahead of biopsy needle tip is excised. Therefore, positioning of needle tip is most important in order to get exact suspicious lesion. The position of needle tip is mainly navigated by medical imaging tools therefore enough contrast between normal and suspicious tissue in medical imaging tools is critical to accuracy of biopsy surgery.[1] However, medical imaging tools cannot give clear contrast between normal and abnormal tissues sometimes.[2] In extreme cases, prostate cancer is hard to be visualized therefore all tissues at 6 to 12 typical position of prostate are excised in order to examine. [2]–[3]