Poster C86, Sunday, March 25, 1:00-3:00 pm, Exhibit Hall C
Adding insult to injury: Effects of cranial radiation treatment on structural volumes and associated memory performance in brain tumour survivors
Ramy Ayoub1,2, Kiran Beera1, Ashley Ferkul1, Jovanka Skocic1, Cynthia de Medeiros1, Eric Bouffet1,2, Donald Mabbott1,2; 1Peter Gilgan Center for Research and Learning, The Hospital for Sick Children, 2University of Toronto
A long-term goal in biomedical sciences is to recruit endogenous repair mechanisms to promote tissue regeneration in response to brain injury. In animal models, metformin has been found to elicit neurogenesis, fostering brain repair. We are conducting a randomized clinical drug trial measuring effects of metformin on brain repair and cognitive restoration in paediatric brain tumour survivors treated with cranial radiation (CR). CR is associated with reduced brain volume (BV) and cognitive deficits. Here we analyzed baseline differences in BV and associated memory performance (MP) as a result of CR in this population to gain greater insight into neuroanatomical and cognitive changes over the trial period. We aim to examine whether a correlation between BV and MP exists and if different forms of CR (focal vs. craniospinal) result in differences in BV and MP. T1-weighted MR images were obtained in 24 participants (male=14). Measures of hippocampal, thalamic, putamen and corpus callosum volumes, and MP were obtained. A partial least squares (PLS) model was used for regression analysis. Linear analyses were used to detect differences in BV and MP as a function of treatment type. PLS analyses revealed that differences in volumes accounted for 91% of the variance in memory scores, suggesting BV is a good predictor of MP. No significant volume or memory differences by treatment type were present, indicating that CR produced homogeneous effects in this population. Upon completion of data collection in December 2017, analyses will examine metformin-related differences in white matter structure, hippocampal volume and cognitive functioning.
Topic Area: NEUROANATOMY