title: Value of C-Arm Cone Beam Computed Tomography Image Fusion in Maximizing the Versatility of Endovascular Robotics.
abstract: BACKGROUND
  To report our initial experience and highlight the value of using intraoperative C-arm cone beam computed tomography (CT; DynaCT(®)) image fusion guidance along with steerable robotic endovascular catheter navigation to optimize vessel cannulation.
  
  
  METHODS
  Between May 2013 and January 2015, all patients who underwent endovascular procedures using DynaCT image fusion technique along with Hansen Magellan vascular robotic catheter were included in this study. As a part of preoperative planning, relevant vessel landmarks were electronically marked in contrast-enhanced multi-slice computed tomography images and stored. At the beginning of procedure, an intraoperative noncontrast C-arm cone beam CT (syngo DynaCT(®), Siemens Medical Solutions USA Inc.) was acquired in the hybrid suite. Preoperative images were then coregistered to intraoperative DynaCT images using aortic wall calcifications and bone landmarks. Stored landmarks were then overlaid on 2-dimensional (2D) live fluoroscopic images as virtual markers that are updated in real-time with C-arm, table movements and image zoom. Vascular access and robotic catheter (Magellan(®), Hansen Medical) was setup per standard. Vessel cannulation was performed based on electronic virtual markers on live fluoroscopy using robotic catheter. The impact of 3-dimensional (3D) image fusion guidance on robotic vessel cannulation was evaluated retrospectively, by assessing quantitative parameters like number of angiograms acquired before vessel cannulation and qualitative parameters like accuracy of vessel ostium and centerline markers.
  
  
  RESULTS
  All 17 vessels were cannulated successfully in 14 patients' attempted using robotic catheter and image fusion guidance. Median vessel diameter at origin was 5.4 mm (range, 2.3-13 mm), whereas 12 of 17 (70.6%) vessels had either calcified and/or stenosed origin from parent vessel. Nine of 17 vessels (52.9 %) were cannulated without any contrast injection. Median number of angiograms required before cannulation was 0 (range, 0-2). On qualitative assessment, 14 of 15 vessels (93.3%) had grade = 1 accuracy (guidewire inside virtual ostial marker). Fourteen of 14 vessels had grade = 1 accuracy (virtual centerlines that matched with the actual vessel trajectory during cannulation).
  
  
  CONCLUSIONS
  In this small series, the experience of using DynaCT image fusion guidance together with a steerable endovascular robotic catheter indicates that such image fusion strategies can enhance intraoperative 2D fluoroscopy by bringing preoperative 3D information about vascular stenosis and/or calcification, angulation, and take off from main vessel thereby facilitating ultimate vessel cannulation.
authors.affiliation: Angiography Division, Siemens Medical Solutions USA Inc., Hoffman Estates, IL.
authors.forename: Ponraj
authors.initials: P
authors.lastname: Chinnadurai
authors.affiliation: Methodist DeBakey Heart & Vascular Center, The Methodist Hospital, Houston, TX. Electronic address: caduran@houstonmethodist.org.
authors.forename: Cassidy
authors.initials: C
authors.lastname: Duran
authors.affiliation: Methodist DeBakey Heart & Vascular Center, The Methodist Hospital, Houston, TX.
authors.forename: Odeaa
authors.initials: O
authors.lastname: Al-Jabbari
authors.affiliation: Methodist DeBakey Heart & Vascular Center, The Methodist Hospital, Houston, TX.
authors.forename: Walid K
authors.initials: WK
authors.lastname: Abu Saleh
authors.affiliation: Methodist DeBakey Heart & Vascular Center, The Methodist Hospital, Houston, TX.
authors.forename: Alan
authors.initials: A
authors.lastname: Lumsden
authors.affiliation: Methodist DeBakey Heart & Vascular Center, The Methodist Hospital, Houston, TX.
authors.forename: Jean
authors.initials: J
authors.lastname: Bismuth
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D019917:Blood Vessel Prosthesis Implantation; D054893:Cone-Beam Computed Tomography; D057510:Endovascular Procedures; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D065287:Robotic Surgical Procedures; D015607:Stents; D016896:Treatment Outcome; D014652:Vascular Diseases / Q000000981:diagnostic imaging* / Q000601:surgery*