title: Time-resolved noncontrast enhanced 4-D dynamic magnetic resonance angiography using multibolus TrueFISP-based spin tagging with alternating radiofrequency (TrueSTAR).
abstract: OBJECTIVE
  The goal of this study was to introduce a new noncontrast enhanced 4D dynamic MR angiography (dMRA) technique termed multibolus TrueFISP-based spin tagging with alternating radiofrequency (TrueSTAR).
  
  
  METHODS
  Multibolus TrueFISP-based spin tagging with alternating radiofrequency was developed by taking advantage of the phenomenon that the steady-state signal of TrueFISP is minimally disturbed by periodically inserted magnetization preparations (e.g., spin tagging) that are sandwiched by two α/2 RF pulses. Both theoretical analysis and experimental studies were carried out to optimize the proposed method which was compared with both pulsed and pseudo-continuous arterial spin labeling-based dMRA in healthy volunteers. Optimized multibolus dMRA was also applied in a patient with arteriovenous malformation to demonstrate its potential clinical utility.
  
  
  RESULTS
  Multibolus dMRA offered a prolonged tagging bolus compared to the standard single-bolus dMRA, and allowed improved visualization of the draining veins in the arteriovenous malformation patient. Compared to pseudo-continuous arterial spin labeling-based dMRA, multibolus dMRA provided visualization of the full passage of the labeled blood with the flexibility for both static and dynamic magnetic resonance angiography.
  
  
  CONCLUSIONS
  By combining the benefits of pulsed and pseudo-continuous arterial spin labeling-based dMRA, multibolus TrueFISP-based spin tagging with alternating radiofrequency can prolong and enhance the tagging bolus without sacrificing imaging speed or temporal resolution.
authors: Department of Neurology, Laboratory of Functional MRI Technology, University of California Los Angeles, Los Angeles, California, USA.
authors: Lirong
authors: L
authors: Yan
authors: Noriko
authors: N
authors: Salamon
authors: Danny J J
authors: DJ
authors: Wang
mesh_terms: D000328:Adult; D001165:Arteriovenous Malformations / Q000175:diagnosis; D005260:Female; D006801:Humans; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male