Dose optimization of contrast-enhanced carotid MR angiography

Eur Radiol. 2005 Sep;15(9):1797-805. doi: 10.1007/s00330-005-2756-3. Epub 2005 May 5.

Abstract

The purpose of this work was to compare the diagnostic performance of a single-contrast or a double-contrast dose of carotid contrast-enhanced MR angiography (MRA). One-hundred nineteen patients (mean age 65+/-14.4 years) underwent carotid contrast-enhanced MRA with a standardized protocol (repetition time/echo 3.73 ms/1.38 ms, flip-angle 25 degrees, acquisition-time 19 s, voxel size 1.2 x 1.2 x 0.9 mm3) on a 1.5-T scanner (Sonata, Siemens-Medical-Systems) using a neck phased-array coil. Contrast agent was administered intravenously at a rate of 3.0 ml/s, either as a single dose (n=57; 0.1 mmol/kg body weight) or as a double dose (n=62; 0.2 mmol/kg body weight) of meglumine gadoterate (0.5 M/l), followed by 30 ml saline. Qualitative image analysis was performed on maximum intensity projections using a five-point scale. Signal intensities were measured at three different vascular levels on both sides to assess the contrast-to-noise ratios (CNRs). Image quality was rated as good or excellent in all cases. A double dose did not influence the efficacy of carotid enhancement (CNR single dose 69.12+/-19.8; CNR double dose 70.01+/-20.7; p = 0.81) compared with a single dose. In both dose groups the mean CNRs were inversely related to bodyweight, despite adjusted contrast volumes (p=0.0005). Double-dose contrast-enhanced carotid MRA is not superior to single-dose MRA, as overall diagnostic performance and quantitative contrast enhancement are equal. Being more cost-efficient, a single-dose administration of contrast agent is recommended for MRA of the carotid arteries.

Publication types

  • Comparative Study

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Carotid Arteries / pathology*
  • Carotid Stenosis / diagnosis
  • Contrast Media / administration & dosage*
  • Female
  • Gadolinium / administration & dosage
  • Heterocyclic Compounds / administration & dosage
  • Humans
  • Image Enhancement / methods*
  • Image Processing, Computer-Assisted / methods
  • Injections, Intravenous
  • Magnetic Resonance Angiography / methods*
  • Male
  • Middle Aged
  • Organometallic Compounds / administration & dosage
  • Prospective Studies
  • Stroke / diagnosis

Substances

  • Contrast Media
  • Heterocyclic Compounds
  • Organometallic Compounds
  • gadolinium 1,4,7,10-tetraazacyclododecane-N,N',N'',N'''-tetraacetate
  • Gadolinium