Towards MRI-Based Autonomous Robotic US Acquisitions: A First Feasibility Study.
Robotic ultrasound has the potential to assist and guide physicians during interventions. In this work, we present a set of methods and a workflow to enable autonomous MRI-guided ultrasound acquisitions. Our approach uses a structured-light 3D scanner for patient-to-robot and image-to-patient calibration, which in turn is used to plan 3D ultrasound trajectories. These MRI-based trajectories are followed autonomously by the robot and are further refined online using automatic MRI/US registration. Despite the low spatial resolution of structured light scanners, the initial planned acquisition path can be followed with an accuracy of 2.46 ± 0.96 mm. This leads to a good initialization of the MRI/US registration: the 3D-scan-based alignment for planning and acquisition shows an accuracy (distance between planned ultrasound and MRI) of 4.47 mm, and 0.97 mm after an online-update of the calibration based on a closed loop registration.
Christoph
C
Hennersperger
Bernhard
B
Fuerst
Salvatore
S
Virga
Oliver
O
Zettinig
Benjamin
B
Frisch
Thomas
T
Neff
Nassir
N
Navab
D005240:Feasibility Studies; D006801:Humans; D021621:Imaging, Three-Dimensional; D008279:Magnetic Resonance Imaging; D012371:Robotics; D014463:Ultrasonography