Target evolution modeling for robotized adaptive radiotherapy

Adaptive Radiotherapy Treatment (ART) of cancerous organs is based on manipulating Autonomous Robotic System (ARS) used for radiation. After each treatment session, the biological organ is subject to deformation. Treatment efficiency depends highly on predicting successfully the shape of the deformable organ, being treated, prior to commencement of a new session. We begin our study by focusing on recent methods being implemented in adaptive radiotherapy treatment. Then we investigate the structural organization of treatment method from technological and biological perspectives by applying the concept of System of Systems (SoS). Moreover, we present our contribution to ART by means of a predictive model that anticipates the deformation of cancerous organ (Biological System) and issue appropriate control commands needed for adapting the ARS (Technological System). In order to do this issue, we propose in this paper a modeling evolution of a biological target to be treated or avoided during the robotized radiation sessions. For this, a bi-cubic Bézier spline surface method has been applied to reconstruct the organ in 3D dimension. The reconstruction of an organ will allows us to track the deformation of biological organ. The results show that the studied organ (Parotid) is smoothly reconstructed and its center of gravity is identified kinematicaly after each treatment session, in order to elaborate a predictive model-based approach for adaptive robotized radiotherapy.