Abstract
<jats:title>Abstract</jats:title> <jats:p>Numerical human models are essential to advance medical device design, safety assessment, and study how anatomical development influences physiological processes. Despite increasing availability of pediatric models, a critical gap remains in high-resolution, non-morphed whole-body models representing children around one year of age. Existing pediatric models are often derived from morphing older anatomies or lack sufficient tissue segmentation to accurately capture early developmental anatomy.</jats:p> <jats:p>This study introduces Thalia, a non-morphed, high-resolution numerical model of a healthy 10-month-old female. The model was constructed by segmenting 442 tissues from Magnetic Resonance Imaging data. Brain tissues were automatically segmented using an infant-specific FreeSurfer framework, followed by semi-automated and manual refinement in 3DSlicer. The model was validated by expert review and quantitative comparison with age-matched anatomical values reported in the literature. The resulting whole-body model provides detailed anatomical representation across the brain, musculoskeletal system, vasculature, and internal organs, enabling realistic assignment of tissue-specific properties for computational studies. It provides a versatile platform for pediatric medical device development, dosimetry, safety assessment, and bioelectromagnetic simulations. This pediatric numerical anatomical model is openly available as an open-source resource.</jats:p> <jats:sec> <jats:title>Highlights</jats:title> <jats:list list-type="bullet"> <jats:list-item> <jats:p>High-resolution model of a 10-month-old child developed from MRI data</jats:p> </jats:list-item> <jats:list-item> <jats:p>442 tissues segmented to capture early anatomical development accurately</jats:p> </jats:list-item> <jats:list-item> <jats:p>Model validated against expert review and age-matched anatomical data</jats:p> </jats:list-item> <jats:list-item> <jats:p>Illustrative Example of a pediatric transcranial magnetic stimulation use case</jats:p> </jats:list-item> </jats:list> </jats:sec>