title: Whole-brain vessel wall MRI: A parameter tune-up solution to improve the scan efficiency of three-dimensional variable flip-angle turbo spin-echo.
abstract: To propose and evaluate a parameter tune-up solution to expedite a three-dimensional (3D) variable-flip-angle turbo spin-echo (TSE) sequence for whole-brain intracranial vessel wall (IVW) imaging.
  
  
  
  Elliptical k-space sampling and prolonged echo train length (ETL), were used to expedite a 3D variable-flip-angle TSE-based sequence. To compensate for the potential loss in vessel wall signal, optimal combination of prescribed T2and ETL was experimentally investigated on 22 healthy volunteers at 3 Tesla. The optimized protocol (7-8 min) was then compared with a previous protocol (reference protocol, 11-12 min) in terms of signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), vessel wall sharpness, and wall delineation quality on a 4-point scale (0:poor; 3:excellent) in 10 healthy volunteers. A pilot study of five patients was performed and lesion delineation score was used to demonstrate the diagnostic quality.
  
  
  
  A protocol with ETL = 52 and prescribed T2= 170 ms was deemed an optimized one, which, compared with the reference protocol, provided significantly improved wall SNR (12.0 ± 1.3 versus 10.0 ± 1.1; P = 0.002), wall-lumen CNR (9.7 ± 1.2 versus 8.0 ± 0.9; P = 0.002), wall-CSF CNR (2.8 ± 1.0 versus 1.7 ± 1.0; P = 0.026), similar vessel wall sharpness at both inner (1.59 ± 0.18 versus 1.58 ± 0.14, P = 0.87) and outer (1.71 ± 0.25 versus 1.83 ± 0.30; P = 0.18) boundaries, and comparable vessel wall delineation score for individual segments (1.95-3; P > 0.06). In all patients, atherosclerotic plaques (10) or wall dissection (5) were identified with a delineation score of 3 or 2.
  
  
  
  A parameter tune-up solution can accelerate 3D variable-flip-angle TSE acquisitions, particularly allowed for expedited whole-brain IVW imaging with preserved wall delineation quality.
  
  
  
  2. Technical Efficacy: Stage 1 J. MAGN. RESON. IMAGING 2017;46:751-757.
authors.affiliation: Department of Radiology, Xuanwu Hospital, Beijing, China.|Biomedical Imaging Research Institute, Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, California, USA.
authors.forename: Qi
authors.initials: Q
authors.lastname: Yang
authors.affiliation: Biomedical Imaging Research Institute, Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, California, USA.|Department of Bioengineering, University of California, Los Angeles, California, USA.
authors.forename: Zixin
authors.initials: Z
authors.lastname: Deng
authors.affiliation: MR R&D, Siemens Healthcare, Los Angeles, California, USA.
authors.forename: Xiaoming
authors.initials: X
authors.lastname: Bi
authors.affiliation: Department of Neurology, Cedars-Sinai Medical Center, Los Angeles, California, USA.
authors.forename: Shlee S
authors.initials: SS
authors.lastname: Song
authors.affiliation: Department of Neurology, Cedars-Sinai Medical Center, Los Angeles, California, USA.
authors.forename: Konrad H
authors.initials: KH
authors.lastname: Schlick
authors.affiliation: Department of Neurosurgery, Cedars-Sinai Medical Center, Los Angeles, California, USA.
authors.forename: Nestor R
authors.initials: NR
authors.lastname: Gonzalez
authors.affiliation: Biomedical Imaging Research Institute, Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, California, USA.|Department of Bioengineering, University of California, Los Angeles, California, USA.
authors.forename: Debiao
authors.initials: D
authors.lastname: Li
authors.affiliation: Biomedical Imaging Research Institute, Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, California, USA.
authors.forename: Zhaoyang
authors.initials: Z
authors.lastname: Fan
mesh_terms: D000328:Adult; 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; D015203:Reproducibility of Results; D059629:Signal-To-Noise Ratio
keywords: 3D TSE; intracranial vessel wall; magnetic resonance imaging; vessel wall imaging; whole brain