title: Towards direct head navigation for robot-guided transcranial magnetic stimulation using 3D laserscans: Idea, setup and feasibility.
abstract: Direct tracking is more robust than tracking that is based on additional markers. 3D laser scans can be used for direct tracking because they result in a 3D data set of surface points of the scanned object. For head-navigated robotized systems, it is crucial to know where the patient's head is positioned relatively to the robot. We present a novel method to use a 3D laserscanner for direct head navigation in the robotized TMS system that places a coil on the patient's head using an industrial robot. First experimental results showed a translational error < 2mm in the robot hand-eye-calibration with the laserscanner. The rotational error was 0.75° and the scaling error < 0.001. Furthermore, we found that the error of a scanned head to a reference head image was < 0.2mm using ICP. These results have shown that a direct head navigation is feasible for the robotized TMS system. Additional effort has to be made in future systems to speed up the compution time for real time capability.
authors.affiliation: Institute for Robotics and Cognitive Systems, University of Lübeck, 23538, Germany. richter@rob.uni-luebeck.de
authors.forename: Lars
authors.initials: L
authors.lastname: Richter
authors.forename: Ralf
authors.initials: R
authors.lastname: Bruder
authors.forename: Alexander
authors.initials: A
authors.lastname: Schlaefer
authors.forename: Achim
authors.initials: A
authors.lastname: Schweikard
mesh_terms: D000465:Algorithms; D001698:Biomedical Engineering / Q000379:methods; D002138:Calibration; D004867:Equipment Design; D006257:Head / Q000473:pathology; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000295:instrumentation; D021621:Imaging, Three-Dimensional / Q000379:methods*; D007834:Lasers; D008279:Magnetic Resonance Imaging / Q000379:methods; D019047:Phantoms, Imaging; D012371:Robotics; D012984:Software; D013997:Time Factors; D050781:Transcranial Magnetic Stimulation / Q000295:instrumentation* / Q000379:methods