Measuring the impact of treatment on memory functions in pediatric posterior fossa tumor survivors using diffusion tensor imaging

•DTI quantified brain damage and memory loss in posterior fossa tumor survivors.•Higher DTI metrics for memory-related brain areas in PFT suvivors.•DTI metrics correlated closely with memory deficits and dose to some structures.•DTI metrics could be used as markers of memory impairment. The aim of the present prospective exploratory study was to investigate the long-term impact of treatment on brain structure integrity and memory functions in pediatric posterior fossa tumor (PFT) survivors using diffusion tensor imaging (DTI), to determine whether the latter could provide useful biomarkers of memory impairment. Sixty participants were included in this study, divided into three groups: 22 irradiated PFT, 17 non-irradiated PFT, and 21 healthy controls. All underwent memory tests and multimodal MRI, including a DTI sequence. Mean diffusivity and fractional anisotropy values were extracted for bilateral brain structures involved in memory, in order to carry out between-group comparisons and calculate correlations with memory test scores and radiotherapy doses. Statistical tests were two-sided, and p values