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Abstract #0271

The Fixation Protocol Alters Brain Morphology in ex-vivo MRI Mouse Phenotyping

A. Elizabeth de Guzman1, 2, Michael D. Wong1, 2, Jacqueline A. Gleave1, Brian J. Nieman1, 2

1Mouse Imaging Centre, Hospital for Sick Children, Toronto, Ontario, Canada; 2Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada

Despite the common use of chemically fixed tissue for MRI morphometric analysis of the rodent brain, limited details are available describing how the fixation protocol may alter brain morphology. In this study, fixed mouse brain samples were imaged repeatedly during fixation in order to determine the effect that changes in fixation time has on structure volume. Each structure in the brain changed in volume at different rates with fixation time, where structures near the ventricular system decreased in size while the ventricles expanded. Caution should be taken to maintain consistency with fixation protocols, as within study changes may masquerade as phenotypic differences.

Keywords

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