Toward teleoperated needle steering under continuous MRI guidance for prostate percutaneous interventions.

Abstract

To propose a human-operated in-room master-slave bevel-tip needle steering system under continuous MRI guidance for prostate biopsy, in which the patient is kept in the scanner at all times and the process of needle placement is under continuous control of the physician. A 2-DOF MRI-compatible needle steering module is developed and integrated with an existing 4-DOF transperineal robot, creating a 6-DOF robotic platform for prostate interventions. An MRI-compatible 2-DOF master robot is also developed to enable remote needle steering. An MRI-compatible 2-DOF force/torque sensor was used on the master side. Bevel-tip needle steering is implemented in order to compensate for the targeting error due to needle-tissue interaction. MRI-compatibility results demonstrated maximum 20% loss in signal to noise ratio (SNR). Robot functionality was not influenced by the magnetic field. Targeting error was reduced from 4.2 mm to 0.9 mm as a result of bevel-tip needle steering. The feasibility of teleoperated bevel-tip needle steering using the proposed system was shown in a phantom experiment. Copyright © 2015 John Wiley & Sons, Ltd.