Abstract #0018

Alterations in Brain Development Induced by Whole-Brain Irradiation in Young Mice

Lisa M. Gazdzinski¹, Kyle Cormier¹, C Shun Wong²,³, Jason P. Lerch¹, Brian J. Nieman¹

¹Mouse Imaging Centre, Hospital for Sick Children, Toronto, Ontario, Canada; ²Radiation Oncology, Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada; ³Radiation Oncology, University of Toronto, Toronto, Ontario, Canada

Cranial radiotherapy for the treatment of childhood cancer has been implicated in the development of progressive neurocognitive dysfunction, but the mechanism remains poorly understood. Using longitudinal in vivo MRI, this study identified regions of the developing mouse brain most sensitive to irradiation at a young age. Irradiation led to bilateral decreases in growth rate and volume in both white and gray matter regions. The time course varied among brain structures and apparent recovery was observed in a subset of structures. The systematic approach used in this work will serve as a valuable tool for investigating neuroprotective strategies to mitigate neurocognitive late effects.