CoBra: Towards Adaptive Robotized Prostate Brachytherapy under MRI Guidance

This paper presents a novel concept for robotized adaptive prostate Brachytherapy (BT) under Magnetic Resonance Imaging (MRI). The Cooperative Brachytherapy (CoBra) concept with compact modular design robot-guide is capable of serving mount of Low Dose Rate (LDR-BT), High Dose Rate (HDR-BT), and Biopsy modules and operate in-bore 3 Tesla MRI. CoBra integrates the multi-components - radiotherapy, imaging, needle, robot-guide as one global system. CoBra MR-robot is a 5 degrees-of-freedom, actuated using non-magnetic piezo-ultrasonic motors. CoBra Robot intends to place BT seeds to the patient positioned in-bore in lithotomy under MRI-feedback control for the purpose of adaptive brachytherapy. The robot is capable of posing biopsy and BT needle modules for both straight and oblique orientation. It is controlled with an absolute sensor for position sensing. The paper presents recent advances in designing a robotic system for adaptive tumor-targeting in-bore intraoperatively under real-time MRI.