Advances in computational anthropomorphic phantoms and Monte Carlo-based dosimetry: A review

The application of computational anthropomorphic phantoms has become imperative in the field of radiation dosimetry because they facilitate anatomically faithful simulations of energy deposition within the human body. Their development reflects significant advances in computational modeling, with a transition from early stylized geometries to voxel-based, mesh-based, and Non-Uniform Rational B-Splines (NURBS) representations. The recent introduction of ICRP mesh-type reference computational phantoms (MRCPs), including advanced maternal and fetal models, has significantly improved the representation of anatomical heterogeneity. When coupled with Monte Carlo simulation codes (e.g., EGSnrc, MCNP, Geant4, PENELOPE, GATE, and TOPAS), these phantoms offer robust frameworks for calculating radiation transport. Additionally, a transition is underway in the dosimetric paradigm, marked by a shift from macroscopic organ assessments that utilize Condensed History algorithms to subcellular microdosimetry that relies on event-by-event Track Structure codes. Consequently, recent advances have extended their applications in a range of disciplines, including radiotherapy, nuclear medicine, and diagnostic imaging. These advances have also been used in vivo monitoring calibration and modeling of complex radiobiological effects at the DNA level via platforms like TOPAS-nBio. Artificial intelligence and digital-twin approaches are increasingly being explored as tools to support individualized dosimetry and adaptive treatment planning. This review delineates historical developments, methodological breakthroughs, and emerging trends in this field, highlighting the emergence of a new research frontier at the intersection of physics, biology, and computer science for personalized radiation dosimetry.