title: New-Generation Laser-lithographed Dual-Axis Magnetically Assisted Remote-controlled Endovascular Catheter for Interventional MR Imaging: In Vitro Multiplanar Navigation at 1.5 T and 3 T versus X-ray Fluoroscopy.
abstract: OBJECTIVE
  To assess the feasibility of multiplanar vascular navigation with a new magnetically assisted remote-controlled (MARC) catheter with real-time magnetic resonance (MR) imaging at 1.5 T and 3 T and to compare it with standard x-ray guidance in simulated endovascular catheterization procedures.
  
  
  METHODS
  A 1.6-mm-diameter custom clinical-grade microcatheter prototype with lithographed double-saddle coils at the distal tip was deflected with real-time MR imaging. Two inexperienced operators and two experienced operators catheterized anteroposterior (celiac, superior mesenteric, and inferior mesenteric arteries) and mediolateral (renal arteries) branch vessels in a cryogel abdominal aortic phantom. This was repeated with conventional x-ray fluoroscopy by using clinical catheters and guidewires. Mean procedure times and percentage success data were analyzed with linear mixed-effects regression.
  
  
  RESULTS
  The MARC catheter tip was visible at 1.5 T and 3 T. Among inexperienced operators, MARC MR imaging guidance was not statistically different from x-ray guidance at 1.5 T (67% successful vessel selection turns with MR imaging vs 76% with x-ray guidance, P = .157) and at 3 T (75% successful turns with MR imaging vs 76% with x-ray guidance, P = .869). Experienced operators were more successful in catheterizing vessels with x-ray guidance (98% success within 60 seconds) than with 1.5-T (65%, P < .001) or 3-T (75%) MR imaging. Among inexperienced operators, mean procedure time was nearly equivalent by using MR imaging (31 seconds) and x-ray guidance (34 seconds, P = .436). Among experienced operators, catheterization was faster with x-ray guidance (20 seconds) compared with 1.5-T MR imaging (42 seconds, P < .001), but MARC guidance improved at 3 T (31 seconds). MARC MR imaging guidance at 3 T was not significantly different from x-ray guidance for the celiac (P = .755), superior mesenteric (P = .358), and inferior mesenteric (P = .065) arteries.
  
  
  CONCLUSIONS
  Multiplanar navigation with a new MARC catheter with real-time MR imaging at 1.5 T and 3 T is feasible and comparable to x-ray guidance for anteroposterior vessels at 3 T in a vascular phantom.
authors.affiliation: From the Department of Radiology and Biomedical Imaging, University of California-San Francisco, 505 Parnassus Ave, L-352, San Francisco, CA 94143-0628.
authors.forename: Parham
authors.initials: P
authors.lastname: Moftakhar
authors.affiliation: From the Department of Radiology and Biomedical Imaging, University of California-San Francisco, 505 Parnassus Ave, L-352, San Francisco, CA 94143-0628.
authors.forename: Prasheel
authors.initials: P
authors.lastname: Lillaney
authors.affiliation: From the Department of Radiology and Biomedical Imaging, University of California-San Francisco, 505 Parnassus Ave, L-352, San Francisco, CA 94143-0628.
authors.forename: Aaron D
authors.initials: AD
authors.lastname: Losey
authors.affiliation: From the Department of Radiology and Biomedical Imaging, University of California-San Francisco, 505 Parnassus Ave, L-352, San Francisco, CA 94143-0628.
authors.forename: Daniel L
authors.initials: DL
authors.lastname: Cooke
authors.affiliation: From the Department of Radiology and Biomedical Imaging, University of California-San Francisco, 505 Parnassus Ave, L-352, San Francisco, CA 94143-0628.
authors.forename: Alastair J
authors.initials: AJ
authors.lastname: Martin
authors.affiliation: From the Department of Radiology and Biomedical Imaging, University of California-San Francisco, 505 Parnassus Ave, L-352, San Francisco, CA 94143-0628.
authors.forename: Bradford R H
authors.initials: BR
authors.lastname: Thorne
authors.affiliation: From the Department of Radiology and Biomedical Imaging, University of California-San Francisco, 505 Parnassus Ave, L-352, San Francisco, CA 94143-0628.
authors.forename: Ronald L
authors.initials: RL
authors.lastname: Arenson
authors.affiliation: From the Department of Radiology and Biomedical Imaging, University of California-San Francisco, 505 Parnassus Ave, L-352, San Francisco, CA 94143-0628.
authors.forename: Maythem
authors.initials: M
authors.lastname: Saeed
authors.affiliation: From the Department of Radiology and Biomedical Imaging, University of California-San Francisco, 505 Parnassus Ave, L-352, San Francisco, CA 94143-0628.
authors.forename: Mark W
authors.initials: MW
authors.lastname: Wilson
authors.affiliation: From the Department of Radiology and Biomedical Imaging, University of California-San Francisco, 505 Parnassus Ave, L-352, San Francisco, CA 94143-0628.
authors.forename: Steven W
authors.initials: SW
authors.lastname: Hetts
mesh_terms: D002406:Catheterization, Peripheral / Q000295:instrumentation* / Q000379:methods; D004058:Diffusion; D005240:Feasibility Studies; D005471:Fluoroscopy; D006801:Humans; D053783:Magnetic Resonance Imaging, Interventional / Q000295:instrumentation* / Q000379:methods*; D008280:Magnetics; D010477:Perfusion; D019047:Phantoms, Imaging