title: Active two-channel 0.035'' guidewire for interventional cardiovascular MRI.
abstract: OBJECTIVE
  To develop an "active" (receiver-coil) clinical-grade guidewire with enhanced visibility for magnetic resonance imaging (MRI) and favorable mechanical characteristics for interventional MRI procedures that require conspicuous intravascular instruments distinguishable from surrounding tissues.
  
  
  METHODS
  We designed a 0.035-inch guidewire combining two antenna designs on separate channels. A loop antenna visualizes the tip and a dipole antenna visualizes the whole shaft. We compared mechanical characteristics of this guidewire with x-ray alternatives and tested MRI performance at 1.5T in vitro and in vivo in swine.
  
  
  RESULTS
  Images reflected tip position within 0.97 +/- 0.42 mm and afforded whole-shaft visibility under expected conditions without sacrificing device size or handling. We report tip stiffness, torquability, and pushability comparable to commercial interventional guidewires.
  
  
  CONCLUSIONS
  Our clinical-grade 0.035-inch active guidewire is conspicuous under MRI and has mechanical performance comparable to x-ray interventional guidewires. This may enable a range of interventional procedures using real-time MRI.
authors.affiliation: Translational Medicine Branch, Division of Intramural Research, National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland 20892-1061, USA. kocaturko@nhlbi.nih.gov
authors.forename: Ozgur
authors.initials: O
authors.lastname: Kocaturk
authors.forename: Ann H
authors.initials: AH
authors.lastname: Kim
authors.forename: Christina E
authors.initials: CE
authors.lastname: Saikus
authors.forename: Michael A
authors.initials: MA
authors.lastname: Guttman
authors.forename: Anthony Z
authors.initials: AZ
authors.lastname: Faranesh
authors.forename: Cengizhan
authors.initials: C
authors.lastname: Ozturk
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Lederman
mesh_terms: D002318:Cardiovascular Diseases / Q000628:therapy*; D004867:Equipment Design; D006801:Humans; D053783:Magnetic Resonance Imaging, Interventional / Q000295:instrumentation*