Abstract #0446

Traboulsee A, MacKay A, Li D, Laule C, Vavasour I

The purpose of this study was to better define the T2 distribution in MS lesions and NAWM with particular emphasis on identifying potential long T2 components. Forty-eight echo T2-relaxation data was acquired in 20 MS patients. Decreased myelin water, increased geometric mean T2 (GMT2) and increased peak width of the intra/extracellular (IE) peak were observed in MS lesions relative to NAWM. A new water reservoir with a markedly prolonged T2 peak (200-800ms) was identified in 30% of lesions and several NAWM regions. Those lesions with a Long-T2 peak also exhibited longer IE GMT2 than those lesions without a Long-T2 signal.