title: Carotid arterial wall MRI at 3T using 3D variable-flip-angle turbo spin-echo (TSE) with flow-sensitive dephasing (FSD).
abstract: OBJECTIVE
  To evaluate the effectiveness of flow-sensitive dephasing (FSD) magnetization preparation in improving blood signal suppression of three-dimensional (3D) turbo spin-echo (TSE) sequence (SPACE) for isotropic high-spatial-resolution carotid arterial wall imaging at 3T.
  
  
  METHODS
  The FSD-prepared SPACE sequence (FSD-SPACE) was implemented by adding two identical FSD gradient pulses right before and after the first refocusing 180 degrees -pulse of the SPACE sequence in all three orthogonal directions. Nine healthy volunteers were imaged at 3T with SPACE, FSD-SPACE, and multislice T2-weighted 2D TSE coupled with saturation band (SB-TSE). Apparent carotid wall-lumen contrast-to-noise ratio (aCNR(w-l)) and apparent lumen area (aLA) at the locations with residual-blood (rb) signal shown on SPACE images were compared between SPACE and FSD-SPACE. Carotid aCNR(w-l) and lumen (LA) and wall area (WA) measured from FSD-SPACE were compared to those measured from SB-TSE.
  
  
  RESULTS
  Plaque-mimicking flow artifacts identified in seven carotids on SPACE images were eliminated on FSD-SPACE images. The FSD preparation resulted in slightly reduced aCNR(w-l) (P = 0.025), but significantly improved aCNR between the wall and rb regions (P < 0.001) and larger aLA (P < 0.001). Compared to SB-TSE, FSD-SPACE offered comparable aCNR(w-l) with much higher spatial resolution, shorter imaging time, and larger artery coverage. The LA and WA measurements from the two techniques were in good agreement based on intraclasss correlation coefficient (0.988 and 0.949, respectively; P < 0.001) and Bland-Altman analyses.
  
  
  CONCLUSIONS
  FSD-SPACE is a time-efficient 3D imaging technique for carotid arterial wall with superior spatial resolution and blood signal suppression.
authors.affiliation: Department of Radiology, Northwestern University, Chicago, Illinois 60611, USA.
authors.forename: Zhaoyang
authors.initials: Z
authors.lastname: Fan
authors.forename: Zhuoli
authors.initials: Z
authors.lastname: Zhang
authors.forename: Yiu-Cho
authors.initials: YC
authors.lastname: Chung
authors.forename: Peter
authors.initials: P
authors.lastname: Weale
authors.forename: Sven
authors.initials: S
authors.lastname: Zuehlsdorff
authors.forename: James
authors.initials: J
authors.lastname: Carr
authors.forename: Debiao
authors.initials: D
authors.lastname: Li
mesh_terms: D000328:Adult; D000368:Aged; D002339:Carotid Arteries / Q000033:anatomy & histology*; D006801:Humans; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008875:Middle Aged; D055414:Myocardial Perfusion Imaging / Q000379:methods*; D013113:Spin Labels
chemical_list: D013113:Spin Labels