title: Dual-temporal resolution dynamic contrast-enhanced MRI protocol for blood-brain barrier permeability measurement in enhancing multiple sclerosis lesions.
abstract: OBJECTIVE
  To design a more accurate and reproducible technique for the measurement of blood-brain barrier (BBB) permeability in gadolinium-enhancing multiple sclerosis (MS) lesions.
  
  
  METHODS
  Four MS patients were scanned using a new dynamic contrast-enhanced (DCE)-magnetic resonance imaging (MRI) protocol based on an uninterrupted two-part acquisition consisting of an initial part at high temporal and low spatial resolutions and a second part at low temporal and high spatial resolutions. The method preserves both the high spatial resolution needed for the often small size of lesions and the high temporal resolution required during the first minute after injection to sufficiently sample the first-pass bolus. Simulations compared the performance of this new protocol with the conventional one at low temporal and high spatial resolutions throughout.
  
  
  RESULTS
  The BBB permeability estimates changed by up to 33% between the two protocols. The new protocol led to simulated error on K(trans) of 7%-10%, versus 7%-30% with the conventional protocol, and was more robust with respect to offsets between acquisition and injection start times, differences in shape of the first-pass peak, and permeability values.
  
  
  CONCLUSIONS
  The dual-temporal resolution protocol produces improved BBB permeability estimates and provides a more complete view of active inflammatory MS lesion pathology.
authors: McConnell Brain Imaging Centre, Montreal Neurological Institute, Montreal, Quebec, Canada. ileana.jelescu@mail.mcgill.ca
authors: I O
authors: IO
authors: Jelescu
authors: I R
authors: IR
authors: Leppert
authors: S
authors: S
authors: Narayanan
authors: D
authors: D
authors: Araújo
authors: D L
authors: DL
authors: Arnold
authors: G B
authors: GB
authors: Pike