Multi-scale hybrid models for radiopharmaceutical dosimetry with Geant4

The accuracy of radiopharmaceutical absorbed dose distributions computed through Monte Carlo (MC) simulations is mostly limited by the low spatial resolution of 3D imaging techniques used to define the simulation geometry. This issue also persists with the implementation of realistic hybrid models built using polygonal mesh and/or NURBS as they require to be simulated in their voxel form in order to reduce computation times. The existing trade-off between voxel size and simulation speed leads on one side, in an overestimation of the size of small radiosensitive structures such as the skin or hollow organs walls and, on the other, to unnecessarily detailed voxelization of large, homogeneous structures.We developed a set of computational tools based on VTK and Geant4 in order to build multi-resolution organ models. Our aim is to use different voxel sizes to represent anatomical regions of different clinical relevance: the MC implementation of these models is expected to improve spatial resolution in specific anatomical structures without significantly affecting simulation speed. Here we present the tools developed through a proof of principle example. Our approach is validated against the standard Geant4 technique for the simulation of voxel geometries.

[1]  Lydia Maigne,et al.  Use of the GATE Monte Carlo package for dosimetry applications , 2006 .

[2]  Stephen M. Seltzer,et al.  Tables and Graphs of Electron-Interaction Cross Sections from 10 eV to 100 GeV Derived from the LLNL Evaluated Data Library (EEDL), Z=1-100 | NIST , 1991 .

[3]  K. F. Eckerman,et al.  Specific absorbed fractions of energy at various ages from internal photon sources: 6, Newborn , 1987 .

[4]  Christopher M Poole,et al.  Fast Tessellated Solid Navigation in GEANT4 , 2012, IEEE Transactions on Nuclear Science.

[5]  H Kumada,et al.  Multistep Lattice-Voxel method utilizing lattice function for Monte-Carlo treatment planning with pixel based voxel model. , 2011, Applied radiation and isotopes : including data, instrumentation and methods for use in agriculture, industry and medicine.

[6]  V F Cassola,et al.  FASH and MASH: female and male adult human phantoms based on polygon mesh surfaces: I. Development of the anatomy , 2010, Physics in medicine and biology.

[7]  William Schroeder,et al.  The Visualization Toolkit: An Object-Oriented Approach to 3-D Graphics , 1997 .

[8]  X. Xu,et al.  Deformable adult human phantoms for radiation protection dosimetry: anthropometric data representing size distributions of adult worker populations and software algorithms , 2010, Physics in medicine and biology.

[9]  J. H. Hubbell,et al.  Tables and graphs of atomic subshell and relaxation data derived from the LLNL Evaluated Atomic Data Library (EADL), Z=1-100 , 1991 .

[10]  Daniel Lodwick,et al.  The UF family of reference hybrid phantoms for computational radiation dosimetry , 2010, Physics in medicine and biology.

[11]  Ernesto Amato,et al.  Use of the GEANT4 Monte Carlo to determine three-dimensional dose factors for radionuclide dosimetry , 2013 .

[12]  J. W. Vieira,et al.  MAX06 and FAX06: update of two adult human phantoms for radiation protection dosimetry , 2006, Physics in medicine and biology.

[13]  Martin A. Lodge,et al.  124I PET-Based 3D-RD Dosimetry for a Pediatric Thyroid Cancer Patient: Real-Time Treatment Planning and Methodologic Comparison , 2009, Journal of Nuclear Medicine.

[14]  S Marcatili,et al.  Development and validation of RAYDOSE: a Geant4-based application for molecular radiotherapy , 2013, Physics in medicine and biology.

[15]  M Bardiès,et al.  Validation of a personalized dosimetric evaluation tool (Oedipe) for targeted radiotherapy based on the Monte Carlo MCNPX code , 2006, Physics in medicine and biology.

[16]  William E. Lorensen,et al.  Marching cubes: A high resolution 3D surface construction algorithm , 1987, SIGGRAPH.

[17]  Dragan Tubic,et al.  Octree indexing of DICOM images for voxel number reduction and improvement of Monte Carlo simulation computing efficiency. , 2006, Medical physics.

[18]  Chengyu Shi,et al.  A boundary-representation method for designing whole-body radiation dosimetry models: pregnant females at the ends of three gestational periods—RPI-P3, -P6 and -P9 , 2007, Physics in medicine and biology.

[19]  P B Hoffer,et al.  Computerized three-dimensional segmented human anatomy. , 1994, Medical physics.

[20]  Arion F. Chatziioannou,et al.  Compressed Voxels for High-Resolution Phantom Simulations in GATE , 2007, Molecular Imaging and Biology.

[21]  Chan Hyeong Kim,et al.  A polygon-surface reference Korean male phantom (PSRK-Man) and its direct implementation in Geant4 Monte Carlo simulation , 2011, Physics in medicine and biology.

[22]  M. Wirth,et al.  Bladder wall thickness in normal adults and men with mild lower urinary tract symptoms and benign prostatic enlargement , 2000, Neurourology and urodynamics.

[23]  W. S. Snyder,et al.  Estimates of absorbed fractions for monoenergetic photon sources uniformly distributed in various organs of a heterogeneous phantom. , 1974, Journal of nuclear medicine : official publication, Society of Nuclear Medicine.

[24]  L Maigne,et al.  Comparison of GATE/GEANT4 with EGSnrc and MCNP for electron dose calculations at energies between 15 keV and 20 MeV , 2011, Physics in medicine and biology.

[25]  Manuel Bardiès,et al.  Improved realism of hybrid mouse models may not be sufficient to generate reference dosimetric data. , 2013, Medical physics.

[26]  George Loudos,et al.  A dose point kernel database using GATE Monte Carlo simulation toolkit for nuclear medicine applications: comparison with other Monte Carlo codes. , 2012, Medical physics.

[27]  Yuni K Dewaraja,et al.  131I-Tositumomab Radioimmunotherapy: Initial Tumor Dose–Response Results Using 3-Dimensional Dosimetry Including Radiobiologic Modeling , 2010, Journal of Nuclear Medicine.

[28]  Luc Beaulieu,et al.  Layered mass geometry: a novel technique to overlay seeds and applicators onto patient geometry in Geant4 brachytherapy simulations , 2012, Physics in medicine and biology.

[29]  N. Lanconelli,et al.  A free database of radionuclide voxel S values for the dosimetry of nonuniform activity distributions , 2012, Physics in medicine and biology.

[30]  H Paganetti,et al.  Efficient voxel navigation for proton therapy dose calculation in TOPAS and Geant4 , 2012, Physics in medicine and biology.

[31]  Min Cheol Han,et al.  DagSolid: a new Geant4 solid class for fast simulation in polygon-mesh geometry. , 2013, Physics in medicine and biology.

[32]  I. Buvat,et al.  A review of partial volume correction techniques for emission tomography and their applications in neurology, cardiology and oncology , 2012, Physics in medicine and biology.

[33]  W. Segars,et al.  4D XCAT phantom for multimodality imaging research. , 2010, Medical physics.