Robert Allan Brown1, Sridar Narayanan1, Harold Atkins2, Mark S. Freedman3, Douglas L. Arnold1
1Montreal Neurological Institute, McGill University, Montreal, QC, Canada; 2Division of Hematology, Ottawa Hospital Regional Cancer Centre, Ottawa, ON, Canada; 3Department of Medicine (Neurology), the Ottawa Hospital, Ottawa, ON, Canada
Magnetization transfer ratio MRI is a promising technique for measuring in vivo demyelination and remyelination. However, MTR values are scanner and sequence dependent. We propose a normalization technique, based on imaging of a normal control, that maps MTR values to a semi-quantitative scale that is comparable across sites in multicentre trials and between studies. The performance of this technique is compared to an alternative, statistically based technique proposed in the literature.