ELECTRONIC POSTER - ismrm

T2 and between lesion volume and ADC, while FA showed strong negative correlation. Our data thus indicated the potential of
parameters in characterizing the various stages of the de- and re-myelination thus providing useful information on its pathophysiology.
14:00 4515. Cross-Relaxation Imaging of Age-Related Changes in Myelin Mutant Shaking Pup
Alexey A. Samsonov 1 , Andrew L. Alexander 2 , Julia V. Velikina 3 , Ian D. Duncan 4 , Aaron
S. Field 1
1 Department of Radiology, University of Wisconsin, Madison, WI, United States; 2 Departments of Medical
Physics and Psychiatry, University of Wisconsin, Madison, WI, United States; 3 Department of Medical Physics,
University of Wisconsin, Madison, WI, United States; 4 School of Veterinary Medicine, University of
Wisconsin, Madison, WI, United States
We report results of studying of quantitative parameters of two-pool MT (cross-relaxation) model across ages in the shaking (sh) pup,
a canine mutant with a profound paucity of myelin. All qMT measures were sensitive to changes between dysmyelinated and
myelinated dogs. The bound pool fraction f provided the strongest discrimination between myelinated and dysmyelinated dogs
confirming its high sensitivity to myelin content. The observed qMT measures may represent a result of mixing several potentially
distinguishable bound pools including myelin protons. Including additional pool in a MT model may potentially help distinguishing
myelin from other components of bound proton pool.
14:30 4516. Multicomponent Relaxometry (McDESPOT) in the Shaking Pup Model of
Dysmyelination
Samuel Anthony Hurley 1 , Pouria Mossahebi 2 , Alexey A. Samsonov 3 , Andrew L.
Alexander 1,4 , Sean C.L. Deoni 5 , Ron Fisher 6 , Ian D. Duncan 7 , Aaron S. Field, 23
1 Medical Physics, University of Wisconsin, Madison, WI, United States; 2 Biomedical Engineering, University
of Wisconsin, Madison, WI, United States; 3 Radiology, University of Wisconsin, Madison, WI, United States;
4 Psychiatry, University of Wisconsin, Madison, WI, United States; 5 Engineering, Brown University,
Providence, RI, United States; 6 Waisman Lab for Brain Imaging and Behavior, University of Wisconsin,
Madison, WI, United States; 7 Medical Sciences, University of Wisconsin, Madison, WI, United States
mcDESPOT is a recently proposed technique which provides two-component relaxometry using steady-state imaging. The relative
fraction of water in two microstructural compartments may be estimated via the myelin water fraction map. We report initial results
of this technique on the shaking pup myelin mutant. The shaking pup is a canine model which suffers from dysmyelination without
the confounding effects of inflammation or edema, and is thus an excellent model for investigating the sensitivity and specificity of
mcDESPOT parameters to myelin content in the brain.
15:00 4517. Myelin Visualization Using Q-Space MRI
Keigo Hikishima 1,2 , Kanehiro Fujiyoshi 3 , Masayuki Yamada 1,4 , Yuji Komaki 1,2 , Suketaka
Momoshima 5 , Kazuo Yagi 6 , Norikazu Tamaoki 1 , Yoshiaki Toyama 3 , Masaya Nakamura 3 ,
Hideyuki Okano 2
1 Central Institute for Experimental Animals, Kasawaki, Kanagawa, Japan; 2 Department of Physiology, Keio
University; 3 Department of Orthopaedic Surgery, Keio University; 4 School of Health Science, Fujita Health
University; 5 Department of Radiology, Keio University; 6 Graduate School of Health Science, Tokyo
Metropolitan University
One of the most recently developed DWI methodologies is q-space imaging (QSI) which has been used to detect the size of
microstructure using higher b-values. We developed the myelin mapping protocol using QSI by focusing on the strong restriction of
water diffusion in myelin architecture. We compared myelin mapping with histological findings in spinal cords using dysmyelination
mutant mice and monkeys with spinal cord injury. In this study we demonstrated that myelin mapping depicts the presence of myelin
in spinal cord.
MRS of Animal Brain
Hall B Monday 14:00-16:00 Computer 89
14:00 4518. In Vivo MRS Study of Adolescent Rhesus Monkeys with Early Life Stress
Experience
Yumei Yan 1 , Xiaodong Zhang 1 , Brittany Howell 2,3 , Mar Sanchez 2,3
1 Yerkes Imaging Center, Yerkes National Primate Research Center, Emory University, Atlanta, GA, United
States; 2 Psychiatry & Behavioral Sciences, Emory School of Medicine, Atlanta, GA, United States;
3 Psychobiology Division, Yerkes National Primate Research Center, Emory University, Atlanta, GA, United
States
In vivo Magnetic Resonance Spectroscopy (MRS) was used to investigate the metabolic changes in basal ganglia (BG) and anterior
cingulate cortex (ACC) of adolescent rhesus monkeys with Early Life Stress (ELS). The MRS findings suggest that ELS has an
enduring impact on the brains of adolescent male monkeys, potentially reflecting neuropathological alterations or even neuronal loss
in their BG (striatum). Males seem more vulnerable to these long-term alterations than females, supporting previous sex differences in
vulnerability to ELS. The sex differences in Cho striatal concentrations could be due to differences in glial cell proliferation.