Retrospective analysis of geometrical information about parotid and planning target volume to predict the parotid mean dose

Intensity Modulated Radiotherapy (IMRT) is the widely used technique in Head and Neck cancer cases, in which PTV is surrounded by OAR structures, so IMRT planning has a challenge of reducing the OAR Doses. Mainly salvaging parotid, as many times parotid overlaps with the PTV. It's very difficult to know the level to which parotid dose can be reduced maintaining the PTV Coverage. The purpose of this study is to develop a planning tool to improve the plan quality by generating a parotid mean dose predictive model based on the retrospective analysis of geometrical information database about parotid and planning target volume (PTV), just before the planning is done