Thèse
Publié le 5 mars 2018 | Mis à jour le 19 septembre 2018

Yazid TOUILEB 2014-2018 - PhD director: Hamid Ladjal, co-director: Michaël Beuve

équipes LIRIS-SAARA - IPNL-PHABIO

Title: Vers une modélisation adaptative, multi-physique et multi-échelle de l’appareil respiratoire en vue d'une dosimétrie 4D pour la radiothérapie

The estimation of the distribution pattern of energy and dose in respiratory-induced organ motion
constitutes a big challenge in hadron therapy treatment planning and dosimetry, notably for lung cancer in
which many difficulties arose, like tissue densities variation and the tumor position shifting during respiration. All these parameters affect the ranges of protons or ions used in treatment when passing through the matter and can easily induce to unexpected dose distribution. Our work consists of calculating the dose distributions of moving organs by means of Monte Carlo simulations. The dose distributions are calculated using a time-dependent tetrahedral density map describing the internal anatomy and respecting the principle of mass conservation. Unlike methods based on deformable image registration, the deposited energy is accumulated inside each deforming tetrahedron of the meshes, thus overcoming the issues related to dose interpolation. The objective of this thesis is the construction of an adaptive tetrahedral deformable model that can be used in the field of particle matter simulations and also for treatment verification with positron emission tomography or gamma prompt imaging. Besides, technical challenges have to be addressed to optimize this structure, including the improvement of simulation time and the validation of our approach on a real patient case. Furthermore, the validation of the tetrahedral model has to be performed using an anthropomorphic breathing phantom named LuCa incorporating a lung tumor model and a typical thoracic anatomy.
  • Auteur(s)
    Yazid TOUILEB