title: Scoutless stepping-table peripheral contrast-enhanced MR angiography.
abstract: OBJECTIVE
  To evaluate the feasibility of a scoutless method, termed EZ-STEP, for stepping-table peripheral contrast-enhanced magnetic resonance angiography (CE-MRA).
  
  
  METHODS
  This scoutless method involves the use of a stepping-table, fast 3D MRA acquisition that incorporates spatially nonselective radiofrequency (RF) pulses for excitation to reduce the repetition time (TR). The sequence was tested in a phantom. The EZ-STEP protocol was optimized in four healthy volunteers and used in 15 subjects. The image quality was scored in a blinded fashion and compared with conventional MRA in eight patients.
  
  
  RESULTS
  The acquisition speed of the EZ-STEP sequence was approximately 30% faster in the phantom study compared to the conventional MRA sequence. The total examination time for EZ-STEP was 6 minutes, compared to an average of 23 minutes for conventional MRA. The average image quality scores for EZ-STEP and conventional MRA for stations 1-3 were 3.50 vs. 3.06 (P = 0.087), 3.53 vs. 3.00 (P = 0.033), and 2.97 vs. 2.50 (P = 0.090), respectively.
  
  
  CONCLUSIONS
  EZ-STEP is a more efficient method than the conventional approach for stepping-table peripheral CE-MRA, and provides comparable or better image quality. This method shortens the examination time substantially and eliminates the risk of failing to image a vessel because of improper positioning of the scan volume.
authors.affiliation: Department of Radiology, Evanston Northwestern Healthcare Evanston, Illinois 60201, USA. lwei@enh.org
authors.forename: Wei
authors.initials: W
authors.lastname: Li
authors.forename: Anthony T
authors.initials: AT
authors.lastname: Vu
authors.forename: Sean
authors.initials: S
authors.lastname: Tutton
authors.forename: Belinda S Y
authors.initials: BS
authors.lastname: Li
authors.forename: Roland
authors.initials: R
authors.lastname: Bejm
authors.forename: Linda
authors.initials: L
authors.lastname: Pierchala
authors.forename: Robert R
authors.initials: RR
authors.lastname: Edelman
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001157:Arterial Occlusive Diseases / Q000175:diagnosis*; D015331:Cohort Studies; D003287:Contrast Media; D005260:Female; D005263:Femoral Artery / Q000473:pathology; D005682:Gadolinium; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007866:Leg / Q000098:blood supply; D008297:Male; D008875:Middle Aged; D016491:Peripheral Vascular Diseases / Q000175:diagnosis*; D011150:Popliteal Artery / Q000473:pathology; D011336:Probability; D012016:Reference Values; D012680:Sensitivity and Specificity; D013997:Time Factors
chemical_list: D003287:Contrast Media; D005682:Gadolinium