title: Magnetic resonance imaging compatible remote catheter navigation system with 3 degrees of freedom.
abstract: OBJECTIVE
  To facilitate MRI-guided catheterization procedures, we present an MRI-compatible remote catheter navigation system that allows remote navigation of steerable catheters with 3 degrees of freedom.
  
  
  METHODS
  The system consists of a user interface (master), a robot (slave), and an ultrasonic motor control servomechanism. The interventionalist applies conventional motions (axial, radial and plunger manipulations) on an input catheter in the master unit; this user input is measured and used by the servomechanism to control a compact catheter manipulating robot, such that it replicates the interventionalist's input motion on the patient catheter. The performance of the system was evaluated in terms of MRI compatibility (SNR and artifact), feasibility of remote navigation under real-time MRI guidance, and motion replication accuracy.
  
  
  RESULTS
  Real-time MRI experiments demonstrated that catheter was successfully navigated remotely to desired target references in all 3 degrees of freedom. The system had an absolute value error of [Formula: see text]1 mm in axial catheter motion replication over 30 mm of travel and [Formula: see text] for radial catheter motion replication over [Formula: see text]. The worst case SNR drop was observed to be [Formula: see text]3 %; the robot did not introduce any artifacts in the MR images.
  
  
  CONCLUSIONS
  An MRI-compatible compact remote catheter navigation system has been developed that allows remote navigation of steerable catheters with 3 degrees of freedom. The proposed system allows for safe and accurate remote catheter navigation, within conventional closed-bore scanners, without degrading MR image quality.
authors.affiliation: Imaging Research Laboratories, Robarts Research Institute, Western University, London, ON, N6A 5B9, Canada. mtavalla@uwo.ca.
authors.forename: M A
authors.initials: MA
authors.lastname: Tavallaei
authors.affiliation: Imaging Research Laboratories, Robarts Research Institute, Western University, London, ON, N6A 5B9, Canada.
authors.forename: M K
authors.initials: MK
authors.lastname: Lavdas
authors.affiliation: Imaging Research Laboratories, Robarts Research Institute, Western University, London, ON, N6A 5B9, Canada.
authors.forename: D
authors.initials: D
authors.lastname: Gelman
authors.affiliation: Imaging Research Laboratories, Robarts Research Institute, Western University, London, ON, N6A 5B9, Canada.
authors.forename: M
authors.initials: M
authors.lastname: Drangova
mesh_terms: D002404:Catheterization / Q000379:methods*; D057785:Catheters; D004867:Equipment Design; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D012371:Robotics / Q000379:methods*
keywords: Catheterization; MRI-compatible; Magnetic resonance imaging; Master-slave; Real-time systems; Surgical robotics; Telerobotics