Design, Development, and Preliminary Evaluation of a Semi-Automated Active Needle Device for Curvilinear Catheter Implantation

Prostate cancer is the second most common cancer among American males. High-dose-rate brachytherapy for prostate cancer treatment involves temporarily implanting highdose radiation into the prostate gland. In current clinical practice, conventional rigid needles and catheters restrict radiation delivery in straight lines, with no conformity to individual patient anatomy. Our previous studies showed that replacing conventional rectilinear catheters with curvilinear catheters improves the treatment outcomes by allowing patientspecific catheter placements, enhancing dosimetric values, and reducing side effects such as toxicity to organs at risk. This work presents a semi-automated active needle device alongside an innovative brachytherapy template designed for curvilinear catheter implantation. The required curved trajectories were determined by replanning a treatment using curvilinear catheters for an anonymized patient previously treated at our partner institute. The device was tested to execute these curved trajectories. The device was also validated through air and phantom actuation tests and achieved a displacement error of less than 2.89 mm.