Development and Experimental Validation of Force-Sensing Biopsy Needle for MRI-Guided Prostate Biopsy

Abstract A biopsy needle is an essential surgical tool used to extract several pieces of tissue for diagnosing diseases such as prostate cancer. To facilitate cancer diagnosis, a real-time force-sensing biopsy needle comprising a stylet with an outer tubular sleeve (cannula) was developed in this study. For compatibility with magnetic resonance imaging (MRI)-guided prostate biopsy, fiber Bragg grating (FBG) sensors are embedded into the stylet. The performance of the individual stylet and the entire needle was experimentally evaluated, and the resolutions for force measurement were found to be 1.40 mN and 1.60 mN, respectively, with a root mean square error (RMSE) of 5.6 mN; these are sufficient for differentiating normal prostate tissue from cancer tissue. Since FBG sensors are affected by both strain and temperature, the effects of temperature due to the different sensor positions were analyzed to enable temperature compensation for the needle. The real-time force-sensing performance of the needle was evaluated at room temperature by inserting it into the heated chicken breast, which was used to replicate the typical human body temperature. The forces measured using the proposed needle were observed to be in close agreement with reference measurement from a force gauge; specifically, the measurement errors were found to be 0.021 2 N for the proposed biopsy needle.