Robotic System for MRI-Guided Focal Laser Ablation in the Prostate

MRI-conditional robotic platforms have proved to be an effective approach for image-guided interventions. In this study, a computer-assisted, pneumatically actuated robot is designed, built, and tested for MRI-guided prostate cancer focal laser ablation (FLA). The robotic manipulator provides two active planar degrees of freedom (DoFs) by using a customized CoreXY frame and one passive rotational DoF. A remote insertion mechanism improves the surgical workflow by keeping the patients inside the scanner during needle insertion. The robotic manipulator is tested in a 3T MR scanner to evaluate its MR compliance, and the results demonstrated that the signal-to-noise ratio (SNR) variation is less than 8%. The in-scanner template positioning accuracy test demonstrates that the manipulator achieves high targeting accuracy with a mean error of 0.46 mm and a standard deviation of 0.25 mm. Phantom studies have shown that the needle insertion accuracy of the manipulator is within 2 mm (mean = 1.7 mm, standard deviation = 0.2 mm).