Abstract #2483

MTR & T1 Measurements in the Very Preterm Brain Markers for Changes in Tissue Microstructure During Early Development

Revital Nossin-Manor^1,2, Omer Bar-Yosef³, Margot J. Taylor^1,2, Elizabeth J. Donner^3,4, John G. Sled^5,6

¹Diagnostic Imaging, the Hospital for Sick Children, Toronto, ON, Canada; ²Neurosciences & Mental Health, Research Institute, the Hospital for Sick Children, Toronto, ON, Canada; ³Neurology, the Hospital for Sick Children, Toronto, ON, Canada; ⁴Faculty of Medicine, University of Toronto, Toronto, ON, Canada; ⁵Physiology Experimental Medicine, Research Institute, the Hospital for Sick Children, Toronto, ON, Canada; ⁶Medical Biophysics, University of Toronto, Toronto, ON, Canada

Increases in magnetization transfer ratio (MTR) and shortening of relaxometry values manifest maturational changes, which reflect distinct biological properties of tissue that need not be related. To investigate these markers of maturation we correlated MTR and T₁ measurements using scans from fifteen neonates born between 24 and 31 weeks gestational age, scanned after birth. Six structures representing different stages of myelination in the immature brain were segmented. MTR varied linearly with T₁, with similar slopes for all regions studied but significantly different intercepts. Interestingly, a different order of structures was demonstrated for MTR and T₁ values.