title: Phase-sensitive dual-inversion recovery for accelerated carotid vessel wall imaging.
abstract: OBJECTIVE
  Dual-inversion recovery (DIR) is widely used for magnetic resonance vessel wall imaging. However, optimal contrast may be difficult to obtain and is subject to RR variability. Furthermore, DIR imaging is time-inefficient and multislice acquisitions may lead to prolonged scanning times. Therefore, an extension of phase-sensitive (PS) DIR is proposed for carotid vessel wall imaging.
  
  
  METHODS
  The statistical distribution of the phase signal after DIR is probed to segment carotid lumens and suppress their residual blood signal. The proposed PS-DIR technique was characterized over a broad range of inversion times. Multislice imaging was then implemented by interleaving the acquisition of 3 slices after DIR. Quantitative evaluation was then performed in healthy adult subjects and compared with conventional DIR imaging.
  
  
  RESULTS
  Single-slice PS-DIR provided effective blood-signal suppression over a wide range of inversion times, enhancing wall-lumen contrast and vessel wall conspicuity for carotid arteries. Multislice PS-DIR imaging with effective blood-signal suppression is enabled.
  
  
  CONCLUSIONS
  A variant of the PS-DIR method has successfully been implemented and tested for carotid vessel wall imaging. This technique removes timing constraints related to inversion recovery, enhances wall-lumen contrast, and enables a 3-fold increase in volumetric coverage at no extra cost in scanning time.
authors.affiliation: From the Department of Radiology, University Hospital (CHUV) and University of Lausanne (UNIL); and Center for Biomedical Imaging (CIBM), Lausanne, Switzerland.
authors.forename: Gabriele
authors.initials: G
authors.lastname: Bonanno
authors.forename: David
authors.initials: D
authors.lastname: Brotman
authors.forename: Matthias
authors.initials: M
authors.lastname: Stuber
mesh_terms: D000328:Adult; D000465:Algorithms; D002339:Carotid Arteries / Q000033:anatomy & histology*; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D021621:Imaging, Three-Dimensional / Q000379:methods*; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D010363:Pattern Recognition, Automated / Q000379:methods*; D012016:Reference Values; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity