Abstract #2174

Short-Term Stability of T1 & T2 Relaxation Measures in Multiple Sclerosis Normal Appearing White Matter

Alice Liang¹, Irene M. Vavasour², Anthony L. Traboulsee³, Joel Oger³, Donna J. Lang², David K. B. Li², Alex L. MacKay^1,2, Cornelia Laule^2,4

¹Physics & Astronomy, University of British Columbia, Vancouver, BC, Canada; ²Radiology, University of British Columbia, Vancouver, BC, Canada; ³Medicine, University of British Columbia, Vancouver, BC, Canada; ⁴Pathology & Laboratory Medicine, University of British Columbia, Vancouver, BC, Canada

Longitudinal changes in myelin water fraction (MWF) and geometric mean T₂ (GMT₂) of segmented MS normal-appearing white matter (NAWM) have not been investigated. We examine the short-term evolution of MWF, GMT₂ and mean T₁ in MS NAWM based on monthly scanning over 6 months in 18 MS subjects. Histogram metrics derived from quantitative assessment of T₁ and T₂ relaxation in MS NAWM demonstrated short-term stability of mean T₁, MWF and GMT₂. While it is reasonable to hypothesize that diffuse progressive myelin loss occurs throughout MS brain, the timescale of demyelination appears to be greater than 6 months.