Abstract #2092

Myelin Water Fraction Reduction in Multiple Sclerosis Normal Appearing White Matter: Where Are All the Zeroes?

Cornelia Laule^1,2, Shannon H. Kolind³, Irene M. Vavasour¹, Burkhard Mdler², Joel Oger⁴, Anthony L. Traboulsee⁴, Wayne Moore⁵, David KB Li¹, Alex L. MacKay¹

¹Radiology, University of British Columbia, Vancouver, BC, Canada; ²Physics & Astronomy, University of British Columbia, Vancouver, BC, Canada; ³FMRIB Centre, University of Oxford, Oxford, United Kingdom; ⁴Medicine, University of British Columbia, Vancouver, BC, Canada; ⁵Pathology & Laboratory Medicine, University of British Columbia, Vancouver, BC, Canada

Using T₂ relaxation it is possible to measure myelin water fraction in multiple sclerosis (MS) normal appearing white matter (NAWM). Previous work employing a region of interest based approach found reduced myelin water fraction (MWF) in MS NAWM relative to normal white matter in controls. Using an improved 3D T2 relaxation sequence at higher field strength, we also found reduced MWF in MS NAWM which correlated with EDSS. Voxels with lowest MWF values were not uniformly distributed throughout the NAWM, but rather tended to arise near grey/white matter interfaces in the periphery of the brain.