Mri-Guided Targeted Needle Placement During Motion Using Hydrostatic Actuators

Background Magnetic resonance imaging (MRI) has unique advantages for guiding interventions, but the narrow space is a major challenge. This study evaluates the feasibility of a remote-controlled hydrostatic actuator system for MRI-guided targeted needle placement. Methods The effects of the hydrostatic actuator system on MR image quality were evaluated. Using a reference step-and-shoot method (SS) and the proposed actuator-assisted method (AA), two operators performed MRI-guided needle placement in targets (n = 12) in a motion phantom. Results The hydrostatic actuator system exhibited negligible impact on MR image quality. In dynamic targets, AA was significantly more accurate and precise than SS, with mean +/- SD needle-to-target error of 1.8 +/- 1.0 mm (operator 1) and 1.3 +/- 0.5 mm (operator 2). AA reduced the insertion time by 50% to 80% and total procedure time by 25%, compared to SS. Conclusions The proposed hydrostatic actuator system may improve accuracy and reduce procedure time for MRI-guided targeted needle placement during motion.