title: A novel, general-purpose, MR-compatible, manually actuated robotic manipulation system for minimally invasive interventions under direct MRI guidance.
abstract: BACKGROUND
  Performing minimally invasive interventions under direct MRI guidance offers significant advantages. Required accessibility to the patient inside the MRI scanner is fairly limited, and employment of robotic assistance has been proposed. The development of MR-compatible robotic systems entails engineering challenges related to geometric constraints and the magnetic nature of the scanning environment.
  
  
  METHODS
  A novel, general-purpose, MR-compatible robotic manipulation system has been developed for the performance of minimally invasive interventions inside a cylindrical scanner under direct MRI guidance. The system is endowed with five degrees of freedom (DOF), is characterized by a unique kinematics structure and is manually actuated.
  
  
  RESULTS
  The prototype system was shown to exhibit the required MR-compatibility characteristics and a task-space positioning ability of approximately 5 mm. Needle targeting testing demonstrated a 93% success rate in acquiring a 5 mm spherical target. Phantom testing was performed inside a 3 T scanner and results are reported for an experimental study simulating MRI-guided, manipulator-assisted, MR arthrography.
  
  
  CONCLUSIONS
  Robotic assistance provided by the developed manipulator may effectively facilitate the performance of various MRI-guided, minimally invasive interventions inside a cylindrical scanner.
authors.affiliation: KIOS Research Centre, University of Cyprus, Nicosia, Cyprus.
authors.forename: Eftychios G
authors.initials: EG
authors.lastname: Christoforou
authors.forename: Ioannis
authors.initials: I
authors.lastname: Seimenis
authors.forename: Eleni
authors.initials: E
authors.lastname: Andreou
authors.forename: Eleni
authors.initials: E
authors.lastname: Eracleous
authors.forename: Nikolaos V
authors.initials: NV
authors.lastname: Tsekos
mesh_terms: D000465:Algorithms; D000818:Animals; D001696:Biomechanical Phenomena; D003287:Contrast Media / Q000737:chemistry; D004867:Equipment Design; D006801:Humans; D008279:Magnetic Resonance Imaging; D019060:Minimally Invasive Surgical Procedures / Q000295:instrumentation / Q000379:methods*; D056888:Patient Positioning; D019047:Phantoms, Imaging; D015203:Reproducibility of Results; D012371:Robotics; D025321:Surgery, Computer-Assisted / Q000379:methods; D013552:Swine; D013909:Thorax / Q000473:pathology; D014057:Tomography, X-Ray Computed
chemical_list: D003287:Contrast Media
keywords: MR-compatible robots; image-guided interventions; robot design