Abstract: A method of generating a radiotherapy plan for ion therapy, wherein the beam (6) is shaped by means of passive devices is arranged to allow variation in settings of at least one of the passive devices and/or the MU during the delivery of the beam and to control the movement of the patient and/or the beam in such a way as to create an arc. The arc is preferably a continuous arc or includes at least one continuous sub-arc. The method may include forward planning or optimization. In the latter case, the optimization uses an optimization problem set up to allow variation in settings of at least one of the range modulating device (9), the aperture element (11) and the MU during the delivery of the arc. Computer programs control the planning and the delivery.

Abstract: The present disclosure generally relates to the field of radiation treatment. More specifically, the present disclosure generally relates to methods and radiation treatment systems for facilitating a multimodal radiation therapy treatment plan, in particular a multimodal radiation therapy plan employing a combined photon beam and electron beam radiation treatment. According to one example embodiment described in the disclosure, a method may comprise obtaining information related to a set of candidate beam types for the combined photon beam and electron beam radiation treatment; comparing the set of candidate beam types against a selection criterion to establish a subset of beam types from the candidate beam types; and generating the combined photon beam and electron beam radiation treatment plan utilizing the thus established subset of beam types.

Abstract: A method of radiotherapy treatment planning involves dynamic target tracking and beam redirection. A set of 3D images of a patient reflecting a movement of the patient is obtained, and each image is deformably registered with one reference image. The accumulated dose is calculated as the sum of the dose distribution over all phases in dependence of the patient movement and the model of the delivery machine, the dose distribution for each phase being deformed by means of the deformation map for the respective phase, to match the reference image.

Abstract: A radiotherapy treatment planning method for achieving a FLASH radiotherapy treatment plan involves optimizing the plan using an optimization problem that has been designed to maximize the part of the irradiation that will be delivered under FLASH conditions, in particular to an organ at risk, to minimize the damage to the organ at risk.

Abstract: An inverse-planning method (100), by which a treatment plan specifying a non-photon irradiation of a patient including a target volume is generated, comprises: obtaining (110, 112) first and second plan goals in terms of a respective first and second numerical condition on the treatment plan’s photon-equivalent dose as computed using a first and second RBE factor; and generating (114) the treatment plan by an optimization process aiming to satisfy the first, second and any further plan goals, wherein (a) the first and second plan goals apply to volumes which either are included in the TV or are completely or partially separate from the TV and/or (b) the first and second RBE factors are variable. In a further aspect, a data carrier provides a treatment plan with these characteristics together with reporting quantities relating to fulfilment of the first and second plan goals.

Abstract: A computer-based method of optimizing a radiotherapy treatment plan for a patient is proposed, wherein a treatment plan to be provided by one radiation set is optimized taking into account a previously delivered dose delivered by a different radiation set. One of the radiation sets is external beam radiotherapy and the other is brachytherapy.

Abstract: A computer-based method of optimizing a radiotherapy treatment plan for a patient is proposed, wherein a complete treatment comprising both external beam therapy and brachytherapy is optimized in one procedure using an optimization problem comprising an objective function designed to optimize the total dose distribution as a combination of a first dose distribution to be provided by a first radiation set and a second dose distribution to be provided by a second radiation set. One of the radiation sets is external beam radiotherapy and the other is brachytherapy. The optimization is based on a total desired dose for the whole treatment, images of the patient before the treatment starts and an estimated image of the patient after the first radiation set has been delivered.

Abstract: A computer based method of obtaining a 3D image of a part of a patient's body is disclosed, based on a fraction image having a limited field-of-view and extending the field of view with information from an image of the patient's outline, obtained from a surface scan of the patient. Anatomical data from the planning image are preferably used to fill in the outline image, by means of a contour-guided deformable registration between the planning image and contour.

Abstract: A radiotherapy treatment planning method for achieving a FLASH radiotherapy treatment plan involves optimizing the plan using an optimization problem that has been designed to maximize the part of the irradiation that will be delivered under FLASH conditions, in particular to an organ at risk, to minimize the damage to the organ at risk.

Abstract: Better Pareto dose distributions for multi-criteria optimization of treatment plans can be obtained by obtaining at least one reference dose function designed to result in an acceptable reference dose distribution, defining a multi-criteria optimization problem including the at least one reference dose function as at least one optimization function, performing at least two optimization procedures based on the multi-criteria optimization problem to generate a set of at least two possible treatment plans, obtaining a treatment plan to be used for treating the patient, based on the set of possible treatment plans, by selecting one plan or by combining plans.

Abstract: It is provided a method for determining arc costs. The method comprises the steps of: determining a plurality of beam orientations; evaluating a set of at least one cost function comprising an intermediate exposure cost function that is evaluated by performing the substeps of: projecting the at least one target volumes on a beam plane; determining an alignment angle based on a collimator angle value; finding any intermediate area in the beam plane along the alignment angle between areas of the at least one target volume projection; determining a value of the intermediate exposure cost function. The method further comprises the steps of: finding a plurality of arcs, wherein each arc comprises a sequence of a plurality of beam orientations; and calculating, for each arc in the plurality of arcs, at least one arc cost based on the cost function values of the beam orientations of the arc.

Abstract: A method of optimizing a radiation treatment plan of ion treatment, in which the optimization procedure is interrupted, some but not all low-weight spots are discarded and the optimization procedure is resumed with a reduced set of spots. The weight of one or more remaining spots may be increased before resuming the optimization procedure, for example by adding the spot weight of one or more of the discarded spots to one or more of the remaining spots.

Abstract: Better Pareto dose distributions for multi-criteria optimization of treatment plans can be obtained by obtaining at least one reference dose function designed to result in an acceptable reference dose distribution, defining a multi-criteria optimization problem including the at least one reference dose function as at least one optimization function, performing at least two optimization procedures based on the multi-criteria optimization problem to generate a set of at least two possible treatment plans, obtaining a treatment plan to be used for treating the patient, based on the set of possible treatment plans, by selecting one plan or by combining plans.

Abstract: An approximate image of a patient can be provided by the following method: Obtaining a model of the contour of a patient's body or a part of the patient's body, based on a surface scan of the patient Setting at least one interior density or image intensity value for at least a part of the interior of the contour to provide an approximation of the density of the patient's interior Setting an exterior density or image intensity value for the region outside of the contour, Creating an approximate image based on the model of the contour, and the density or image intensity values. The interior density or intensity may be set to a uniform image intensity value for the whole image or one or more regions, such as organs or bone, may be distinguished by different density of image intensity values.

Abstract: A deep learning model may be trained to provide an estimated image of the interior of a patient, based on a number of image sets, each image set comprising an interior image of the interior of a person and a contour image of the person's outer contour at a specific point in time. The model is trained to establish an optimized parametrized conversion function G specifying the correlation between the interior of the person and the persons outer contour based on the image sets. The conversion function G can then be used to provide estimated images of patient's interior based on their contours.

Abstract: A method of radiotherapy treatment planning for creating a plan for delivery of radiation to a patient in at least one particle-based arc is proposed. The delivery time for the plan is reduced by including a penalty in the objective function, designed to limit the number of energy layers and/or the number of energy layer changes.

Abstract: A computer based method of obtaining a 3D image of a part of a patient's body is disclosed, based on a fraction image having a limited field-of-view and extending the field of view with information from an image of the patient's outline, obtained from a surface scan of the patient. Anatomical data from the planning image are preferably used to fill in the outline image, by means of a contour-guided deformable registration between the planning image and contour.

Abstract: A method of optimizing a radiotherapy treatment plan is disclosed, comprising the steps of: a. obtaining a deliverable input treatment plan; b. optimizing the deliverable input treatment plan to obtain an optimized treatment plan, using an objective function and at least one constraint, wherein i. the objective function is related to reducing the plan complexity in terms of minimizing the machine output (MU) and/or minimizing the time required to deliver the plan and/or maximizing the segment area, and/or minimizing jaggedness of the MLC shapes, ii. to ensure that the quality is maintained, the at least one constraint is based on the dose distribution of the input plan, related to maintaining an acceptable dose distribution.

Abstract: A method of optimizing the use of resources in treatment planning involving more than one radiation set delivered to one or more patients, the radiation sets requiring different resources, respectively, wherein the optimization is performed using an optimization problem comprising an optimization function related to the first and second sets of resources. The method may be used for optimizing one plan for one patient, or a number of plans for different patients, in such a way that the available resources are used in the best possible way.

Abstract: A method of generating a radiotherapy plan for ion therapy, wherein the beam (6) is shaped by means of passive devices is arranged to allow variation in settings of at least one of the passive devices and/or the MU during the delivery of the beam and to control the movement of the patient and/or the beam in such a way as to create an arc. The arc is preferably a continuous arc or includes at least one continuous sub-arc. The method may include forward planning or optimization. In the latter case, the optimization uses an optimization problem set up to allow variation in settings of at least one of the range modulating device (9), the aperture element (11) and the MU during the delivery of the arc. Computer programs control the planning and the delivery.