title: Multiband multislab 3D time-of-flight magnetic resonance angiography for reduced acquisition time and improved sensitivity.
abstract: OBJECTIVE
  To explore the use of multiband (MB) imaging in multislab (MS) 3D time-of-flight-magnetic resonance angiography (TOF-MRA) and to improve acquisition time efficiency (TA), inflow contrast and sensitivity in vessel detection.
  
  
  METHODS
  TOF-MRA is commonly used for imaging intracranial vessels. A MB-MS 3D-TOF-MRA sequence was implemented to excite and acquire multiple slabs simultaneously. Controlled aliasing in parallel imaging results in higher acceleration was used in addition to improve the quality of image reconstruction. Compared to a standard protocol which acquired three slabs in total the MB-MS protocol reduced the thickness by 3 while simultaneously acquiring data from 3 slabs. The total TA was also reduced by a factor 3.
  
  
  RESULTS
  This technique maintains contrast-to-noise ratio while reducing TA, compared to standard single-band/MOTSA acquisitions, leading to an increase in CNR/TA of 1.65 compared to the standard protocol. Furthermore, the strong inflow contrast and increased magnetization transfer contrast caused by the MB excitation pulses improves the sharpness of the vessel borders which is reflected by a 5% higher full width at half maximum of the vessel size and a 17% higher slope of the vessel borders compared to the standard single-band acquisition.
  
  
  CONCLUSIONS
  MB-MS 3D-TOF-MRA can appreciably accelerate image acquisition and combines the high spatial resolution of 3D imaging with the additional inflow contrast advantage of thinner slab acquisitions without introducing excessive noise arising from the MB reconstruction.
authors.affiliation: Radboud University Nijmegen, Donders Institute for Brain, Cognition and Behaviour, Donders Centre for Cognitive Neuroimaging, Nijmegen, The Netherlands.
authors.forename: Jenni
authors.initials: J
authors.lastname: Schulz
authors.affiliation: Radboud University Nijmegen, Donders Institute for Brain, Cognition and Behaviour, Donders Centre for Cognitive Neuroimaging, Nijmegen, The Netherlands.
authors.forename: Rasim
authors.initials: R
authors.lastname: Boyacioğlu
authors.affiliation: Radboud University Nijmegen, Donders Institute for Brain, Cognition and Behaviour, Donders Centre for Cognitive Neuroimaging, Nijmegen, The Netherlands.|Erwin L. Hahn Institute for Magnetic Resonance Imaging, UNESCO-Weltkulturerbe Zollverein, Leitstand Kokerei Zollverein, Essen, Germany.
authors.forename: David G
authors.initials: DG
authors.lastname: Norris
mesh_terms: D000328:Adult; D000465:Algorithms; D001921:Brain / Q000098:blood supply / Q000000981:diagnostic imaging; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods*; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D055815:Young Adult
keywords: 3D imaging; SMS; TOF-MRA; angiography; multiband