ESTRO 2022 - Abstract Book

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Abstract book

ESTRO 2022

thalami and right amygdala, where volume increased between ages 5 and 9 years by 9%, 5%, 4% and 6% respectively (average between left and right for bilateral structures). The bilateral accumbens and caudate volumes appeared to decrease with age, but the association was not significant, suggesting these structure volumes are relatively stable between these ages. Whole brain volume was 10% larger in males vs females, leading to significantly smaller structures in females (p<0.05), in the brainstem (6%), left accumbens (11%) as well as bilateral amygdalas (average 12%), hippocampi (average 9%), putamens (average 7%) and thalami (average 8%).

Conclusion The quality of FreeSurfer segmentations was promising, and there was a modest overlap with EPTN atlas structures. The comprehensive list of sub-regions (including e.g. grey and white matter segmentations) available in FreeSurfer could be of interest for post-radiation outcome studies. The performance of FreeSurfer in the presence of tissue deformations (e.g. tumour, surgery, treatment-related effects) is being investigated. In the future, we expect to use tools like FreeSurfer to extract dose to substructures and sequential volume changes including brain atrophy post radiotherapy in large cohorts of patients.

MO-0886 Automatic delineation of head and neck gross tumor volume using multimodal information

H. Bollen 1 , S. Nuyts 1 , S. Willems 2 , F. Maes 2