Development of newborn and 1-year-old reference phantoms based on polygon mesh surfaces

Abstract

The purpose of this study is the development of paediatric reference phantoms for newborn and 1-year-old infants to be used for the calculation of organ and tissue equivalent doses in radiation protection. The study proposes a method for developing anatomically highly sophisticated paediatric phantoms without using medical images. The newborn and 1-year-old hermaphrodite phantoms presented here were developed using three-dimensional (3D) modelling software applied to anatomical information taken from atlases, textbooks and images provided by the Department of Anatomy of the Federal University of Pernambuco, Brazil. The method uses polygon mesh surfaces to model body contours, the shape of organs as well as their positions and orientations in the human body. Organ and tissue masses agree with corresponding data given by the International Commission on Radiological Protection for newborn and 1-year-old reference children. Bones were segmented into cortical bone, spongiosa, medullary marrow and cartilage to allow for the use of μCT images of trabecular bone for skeletal dosimetry. Anatomical results show 3D images of the phantoms' surfaces, organs and skeletons, as well as tables with organ and tissue masses or skeletal tissue volumes. Dosimetric results present comparisons of organ and tissue absorbed doses or specific absorbed fractions between the newborn and 1-year-old phantoms and corresponding data for other paediatric stylised or voxel phantoms. Most differences were found to be below 10%.

Infants and young children modeling method for numerical dosimetry studies: application to plane wave exposure

“…A realistic 8 weeks old model has been built synthetically in Lee et al (2007). Purely synthetic models, such as the one proposed in Cassola et al (2013), are difficult to evaluate since anatomical realism is difficult to guarantee, but have the advantage of proposing a framework to build new models to be able to cover a wider age range. Older children and adults downsizing has been used in Hadjem et al (2005), Nagaoka et al (2008) for example, but they usually fail to take precisely into account the different anatomical variabilities that exist when comparing adults to infants (Wiart et al 2008, Li et al 2015.…”

Generation of infant anatomical models for evaluating electromagnetic field exposures

“…Few infant models (ages between several weeks and 2 years old) are available. These models include University of Florida (UF) hybrid non-uniform rational B-spline (NURBS) phantoms [Lee et al, 2007[Lee et al, , 2010, software-generated baby models [Cassola et al, 2013], Japanese infant models [Hirata et al, 2008], and the baby model from the National Research Center for Environment and Health (GSF) voxel family in Germany [Petoussi-Henss et al, 2002]. Of these, the first two models use scaled tissues/organs from different individuals to form a reference model.…”

Avaliação computacional das doses médicas e ocupacionais durante diagnóstico de COVID-19 em pacientes pediátricos empregando tomografia computadorizada

“…Esta simulação foi realizada por meio do código Monte Carlo MCNPX (PELOWITZ, 2011), em conjunto com objetos simuladores antropomórficos virtuais infantis (de MELO LIMA et al, 2011) e adultos Mash3 e Fash3 (CASSOLA et al, 2010;CASSOLA et al, 2013).…”