title: Concepts for visualization of multidirectional phase-contrast MRI of the heart and large thoracic vessels.
abstract: OBJECTIVE
  Multidirectional phase-contrast magnetic resonance imaging allows the acquisition of time-resolved velocity fields (vectors) of cardiac and vascular blood flow. Its unique ability to provide vectorial flow information promises to give new insights into hemodynamic physiology. However, up to now appropriate and standardized procedures and software tools are missing to take advantage of all the information contained in the data. The objective of this work is to present a new versatile software tool and to demonstrate its practical value for the examination of multidirectional blood flow.
  
  
  METHODS
  An exemplary selection of data sets from healthy volunteers, patients with cardiovascular pathologies, and healthy domestic pigs has been acquired using a phase-contrast magnetic resonance imaging sequence based on FLASH (fast low angle shot) that encodes velocity as field of three-dimensional vectors. For data processing, we have developed a software tool that integrates the whole workflow, including noise filtering, interactive visualization, and flow quantification.
  
  
  RESULTS
  Using the software tool visualization of complex flow data is easily generated within 5 minutes; interactive exploration of the data is possible in real-time. Exemplary physiologic and pathologic flow patterns were visualized in an intuitive manner. The visual results suggest valuable diagnostic information; its significance, however, must be further evaluated together with the development of more specific data processing.
  
  
  CONCLUSIONS
  Multidirectional phase-contrast magnetic resonance imaging is a valuable tool for assessment of cardiac and vascular hemodynamics. With the development of tools that offer standardized and thus comparable visualizations it may be integrated into the clinical routine in the near future.
authors.affiliation: Institute of Computer Science and Engineering, University of Karlsruhe, Haid-und-Neu-Str. 7, 76131, Karlsruhe, Germany. roland.unterhinninghofen@ira.uka.de
authors.forename: Roland
authors.initials: R
authors.lastname: Unterhinninghofen
authors.forename: Sebastian
authors.initials: S
authors.lastname: Ley
authors.forename: Julia
authors.initials: J
authors.lastname: Ley-Zaporozhan
authors.forename: Hendrik
authors.initials: H
authors.lastname: von Tengg-Kobligk
authors.forename: Michael
authors.initials: M
authors.lastname: Bock
authors.forename: Hans-Ulrich
authors.initials: HU
authors.lastname: Kauczor
authors.forename: Gábor
authors.initials: G
authors.lastname: Szabó
authors.forename: Rüdiger
authors.initials: R
authors.lastname: Dillmann
mesh_terms: D000328:Adult; D000465:Algorithms; D000818:Animals; D001013:Aorta, Thoracic / Q000502:physiology*; D016477:Artifacts; D001783:Blood Flow Velocity / Q000502:physiology; D003287:Contrast Media; D003326:Coronary Circulation / Q000502:physiology; D018618:Echocardiography, Doppler, Color / Q000379:methods; D006321:Heart / Q000502:physiology*; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D021621:Imaging, Three-Dimensional / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods*; D023421:Models, Animal; D011673:Pulsatile Flow / Q000502:physiology; D012039:Regional Blood Flow / Q000502:physiology; D012984:Software; D013552:Swine
chemical_list: D003287:Contrast Media