Abstract: A method and a dose planning module for planning a treatment session of a patient by means of a radiation therapy system includes a radiation therapy unit having a fixed radiation focus point. The method includes obtaining a target volume of a region of a patient to be treated during a treatment of a patient in a radiation therapy unit, the target volume being modeled as a three-dimensional voxel representation; selecting an isodose level for the planned treatment; determining shots to be delivered during the treatment, each shot being modeled by a spatial dose volume distribution of radiation represented by a three-dimensional voxel representation, the shape of the spatial distribution depending on the specific collimator setting and the selected isodose level; and selecting shots in a decreasing volume order for the dose planning.

Abstract: A method and a dose planning module for planning a treatment session of a patient by means of a radiation therapy system includes a radiation therapy unit having a fixed radiation focus point. The method includes obtaining a target volume of a region of a patient to be treated during a treatment of a patient in a radiation therapy unit, the target volume being modeled as a three-dimensional voxel representation; selecting an isodose level for the planned treatment; determining shots to be delivered during the treatment, each shot being modeled by a spatial dose volume distribution of radiation represented by a three-dimensional voxel representation, the shape of the spatial distribution depending on the specific collimator setting and the selected isodose level; and selecting shots in a decreasing volume order for the dose planning.

Abstract: A treatment planning method comprises the steps of identifying a plurality of treatment locations and an overall dose to be applied to each, for each specific location identifying the global dose applied at that location by doses aimed at different locations, as a proportion of the dose applied at the respective different location, constructing a dose factor matrix containing for each location, the global doses arising from the dose applied at each other location, inverting the dose factor matrix and multiplying it with a prescription matrix containing the overall doses to be applied to each location, thereby to obtain a resultant matrix containing a local dose for each location. This provides a mathematically straightforward method of deriving the necessary doses to be applied to each target so that, including the global doses delivered while irradiating a different target, each target receives the correct total dose.