title: Contrast-enhanced carotid magnetic resonance angiography: comparison of single-dose and double-dose of gadolinium using the randomly segmented central k-space ordering technique.
abstract: BACKGROUND
  The aim of this study was to evaluate whether the single dose of gadolinium is sufficient for contrast-enhanced magnetic resonance angiography (MRA) of carotid arteries with the use of newly developed randomly segmented central k-space ordering technique called contrast-enhanced timing-robust angiography (CENTRA).
  
  
  METHODS
  A total of 44 patients underwent carotid MRA in a 1.5T MR scanner using a fluoroscopically monitored, manually triggered, CENTRA pulse sequence. Patients were randomly assigned into two groups according to the dose of contrast medium (gadolinium chelate) administered: group 1 referred to those who received double doses (0.2 mmol/kg) and group 2 received single doses (0.1 mmol/kg). The contrast-to-noise (CNR) ratios of the seven regions of interest were calculated. The delineation of nine vascular regions and the degree of venous overlay were evaluated by two blinded readers on a five-point scale.
  
  
  RESULTS
  For quantitative evaluation, the CNRs at the brachiocephalic artery were greater in patients in group 1 than that in group 2 (p = 0.015), while the differences did not differ between the two groups for the remaining regions of interest (p > 0.05). For qualitative evaluation, there were no significant differences between the two groups in delineation of nine vascular regions and venous overlaying (p > 0.05).
  
  
  CONCLUSIONS
  With the use of the CENTRA technique, carotid MRA may be performed using a single dose of gadolinium and the image quality is comparable to that of the standard double dose protocol.
authors.affiliation: Department of Diagnostic Radiology, Chang Gung Memorial Hospital, Taipei.
authors.forename: Yu-Chun
authors.initials: YC
authors.lastname: Lin
authors.forename: Shu-Hang
authors.initials: SH
authors.lastname: Ng
authors.forename: Jian-Chuan
authors.initials: JC
authors.lastname: Chen
authors.forename: Alex Mun-Ching
authors.initials: AM
authors.lastname: Wong
authors.forename: Yau-Yau
authors.initials: YY
authors.lastname: Wai
mesh_terms: D000328:Adult; D000368:Aged; D002339:Carotid Arteries / Q000473:pathology*; D003287:Contrast Media; D005260:Female; D005682:Gadolinium / Q000008:administration & dosage*; D006801:Humans; D007089:Image Enhancement; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D008875:Middle Aged
chemical_list: D003287:Contrast Media; D005682:Gadolinium