title: Efficient flow suppressed MRI improves interscan reproducibility of carotid atherosclerosis plaque burden measurements.
abstract: OBJECTIVE
  To determine if better flow suppression can meaningfully improve the reproducibility of measurements associated with carotid atherosclerotic disease, particularly for lumen and wall areas.
  
  
  METHODS
  Eighteen subjects with carotid artery stenosis identified by duplex ultrasound (11 with 16%-49% stenosis; 7 with 50%-79% stenosis) underwent two carotid magnetic resonance imaging (MRI) examinations on a 3T scanner with a 4-channel phased array coil. High-resolution intermediate-weighted TSE (TR/TE = 4000/8.5 msec, 0.55 mm in-plane resolution, 2 mm slice thickness, 16 slices, 3-minute scan time) with two different flow-suppression techniques (multislice double inversion recovery [mDIR] and motion-sensitized driven-equilibrium [MSDE]) were obtained separately. For each subject, bilateral arteries were reviewed. One radiologist blinded to timepoints, flow suppression techniques, and clinical information measured the arterial lumen area, wall area, and total vessel wall area.
  
  
  RESULTS
  Compared to mDIR, the MSDE technique had a smaller interscan standard deviation (SD) in lumen (SD: 3.6 vs. 5.2 mm(2), P = 0.02), wall area measurements (SD: 4.5 vs. 6.4 mm(2), P = 0.02), and a trend towards smaller SD in total vessel area measurement (SD: 4.4 vs. 4.9 mm(2), P = 0.07).
  
  
  CONCLUSIONS
  The results from this study demonstrate that vessel wall imaging could quantify atherosclerotic plaque measurements more reliably with an improved blood suppression technique. This relationship between flow-suppression efficiency and reproducibility of plaque measurements is important, as more reliable area measurements will be useful in clinical diagnosis and in serial MRI studies that monitor carotid atherosclerotic lesion progression and regression.
authors.affiliation: Department of Radiology, University of Washington, Seattle, Washington 98109, USA.
authors.forename: Li
authors.initials: L
authors.lastname: Dong
authors.forename: Jinnan
authors.initials: J
authors.lastname: Wang
authors.forename: Vasily L
authors.initials: VL
authors.lastname: Yarnykh
authors.forename: Hunter R
authors.initials: HR
authors.lastname: Underhill
authors.forename: Moni B
authors.initials: MB
authors.lastname: Neradilek
authors.forename: Nayak
authors.initials: N
authors.lastname: Polissar
authors.forename: Thomas S
authors.initials: TS
authors.lastname: Hatsukami
authors.forename: Chun
authors.initials: C
authors.lastname: Yuan
mesh_terms: D000368:Aged; D050197:Atherosclerosis / Q000473:pathology; D002339:Carotid Arteries / Q000473:pathology*; D002340:Carotid Artery Diseases / Q000175:diagnosis* / Q000473:pathology*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D014463:Ultrasonography / Q000379:methods