Manipulator for magnetic resonance imaging guided interventions:: Design, prototype and feasibility

The aim of this work is to develop a seven degree of freedom (DOF) remotely controlled manipulator to perform minimally invasive interventions with real-time magnetic resonance imaging (MRI) guidance inside clinical cylindrical scanners. Control of the device is based on MR images collected pre-operatively and in real-time during the procedure. A user interface fuses all sensor information for man-in-the-loop control. Stereotactic guidance uses multislice and/or three-dimensional MR images to set a trajectory of insertion. Free-handed (or manual) guidance uses a master/slave control device, which replicates the kinematics structure of the arm, to control its movement. The control software checks any motion of the manipulator whether it is within an allowable volume extracted from MR images. The device control is performed with a host/target computer configuration. The system is connected to the MR scanner to receive the MR images and send the coordinates of the end-effector for dynamic control of the imaged plane. The manipulator compatibility with the MR environment and image-guided maneuvering was tested on a 1.5 Tesla MR scanner.