초록 ▼

The present invention is directed to a data processing method for determining a treatment plan for radiation therapy treatment of at least two spatially separate targets by means of a treatment device constituted to treat the at least two targets by means of one or more sub-beams during a treatment

The present invention is directed to a data processing method for determining a treatment plan for radiation therapy treatment of at least two spatially separate targets by means of a treatment device constituted to treat the at least two targets by means of one or more sub-beams during a treatment time, the one or more sub-beams constituting at least one treatment beam which is to pass through the at least two targets in accordance with a treatment plan during the treatment time, the treatment device being further constituted to allow for simultaneous treatment of the at least two targets by at least two of the sub-beams at least during a time interval during the treatment time.

대표청구항 ▼

1. A data processing method for determining a treatment plan for radiation therapy treatment of at least two spatially separate targets by means of a treatment device constituted to treat the at least two targets by means of one or more sub-beams during a treatment time, the one or more sub-beams co

1. A data processing method for determining a treatment plan for radiation therapy treatment of at least two spatially separate targets by means of a treatment device constituted to treat the at least two targets by means of one or more sub-beams during a treatment time, the one or more sub-beams constituting at least one treatment beam which is to pass through the at least two targets in accordance with a treatment plan during the treatment time, the treatment device being further constituted to allow for simultaneous treatment of the at least two targets by at least two of the sub-beams at least during a time interval during the treatment time, the method comprising the following steps performed by a computer: acquiring target data describing spatial information on the at least two spatially separate targets in a patient's body;acquiring treatment beam constraint data which allow determination of potential treatment plans which can be realized by the treatment device and which potential treatment plans describe potential arrangements of the at least one treatment beam, referred to as potential treatment beam arrangements;acquiring treatment beam criteria data describing criteria for the treatment of the at least two targets by the at least one treatment beam, the criteria comprising a radiation reduction criterion which describes that a treatment plan is allowed to be determined which describes a non-simultaneous treatment of the at least two targets at least for a time interval during the treatment time if this treatment plan describes that parts of the patient's body outside the at least two targets are less exposed to treatment radiation, in particular at least to a predetermined extent, compared to the case of a treatment plan which describes a simultaneous treatment of the at least two targets during the treatment time; anddetermining the treatment plan which fulfils the radiation reduction criterion based on the target data, the treatment beam constraint data and the treatment beam criteria data. 2. The method of claim 1, wherein the radiation reduction criterion comprises the following criteria a) and b), in particular is represented by the following criteria a) and b): a) the criterion a) describing that, if projecting the at least two targets into a plane perpendicular to a spatially separate one of the one or more sub-beams and if projecting the cross sectional area of the spatially separate sub-beam into the plane, then there lies not more than one of the at least two projected spatially separate targets spatially separate, in particular by at least a predetermined distance, within the projected cross sectional area, in particular at least for not longer than a predetermined time; andb) the criterion b) allowing that the treatment plan describes that the at least one treatment beam does not pass simultaneously through all of the at least two targets at least for a time interval during treatment in order to fulfil the criteria a), wherein in particular this is only allowed if this results in a reduction of the exposure of the parts of the patient's body outside the at least two targets at least to the predetermined extent. 3. The method according to claim 2 wherein, in particular if no treatment plan can be determined which describes the simultaneous treatment and fulfils the radiation reduction criterion, in particular if the at least one treatment beam cannot pass simultaneously through all of the at least two targets during treatment in order to fulfil the radiation reduction criterion, in particular then the treatment plan is determined based on a set of targets, the set of targets describing targets selected out of the at least two targets for the simultaneous treatment by the at least one treatment beam as a function of time and wherein each of the at least two targets is selected at least for a time interval of the treatment time and wherein at least for a time interval during treatment time not all of the at least two targets are selected. 4. The method of claim 3, wherein the number of the targets in the set of targets is maximized for determining the treatment plan based on the target data, the treatment beam constraint data and the treatment beam criteria data. 5. The method of claim 3, wherein the set of targets is determined so that the treatment time is minimized based on the target data, the treatment beam constraint data and the treatment beam criteria data. 6. The method of claim 1, wherein, in particular if no treatment plan can be determined which describes the simultaneous treatment and fulfils the radiation reduction criterion, in particular if the at least one treatment beam cannot pass simultaneously through all of the at least two targets during treatment in order to fulfil the radiation reduction criterion, in particular then the treatment plan is determined based on a set of targets, the set of targets describing targets selected out of the at least two targets for the simultaneous treatment by the at least one treatment beam as a function of time and wherein each of the at least two targets is selected at least for a time interval of the treatment time and wherein at least for a time interval during treatment time not all of the at least two targets are selected; wherein the set of targets is determined by determining a candidate set, the candidate set being determined by omitting one or more of the at least two targets during a first time interval during the treatment time, by including the omitted one or more of the at least two targets into the candidate set during a second time interval outside the first time interval and during the treatment time and by determining whether the treatment plan can be determined for the candidate set and by determining the candidate set to be the set of targets if the treatment plan can be determined. 7. The method of claim 6, wherein the candidate set is determined by omitting one or more of the at least two targets during a time interval during which a potential treatment plan violates a volume reduction criterion, describing that, if projecting the at least two targets into a plane perpendicular to a spatially separate one of the one or more sub-beams and if projecting the cross sectional area of the spatially separate sub-beam into the plane, then there lies not more than one of the at least two projected spatially separate targets spatially separate, in particular by at least a predetermined distance, within the projected cross sectional area, in particular at least for not longer than a predetermined time, the potential treatment plan fulfilling the condition that all of the at least two targets are simultaneously treated all over the treatment time, the time interval being referred to as violation time interval, and by including the omitted one or more of the at least two targets into the candidate set during a time interval outside the violation time interval and inside the treatment time. 8. The method of claim 1, wherein the treatment plan is determined by combining sub-treatment plans which are to be performed one after the other during treatment time and which respectively describe treatment of a sub-set of the at least two targets, the sub-treatment plans being determined based on the spatial information on the targets of the respective sub-set, the treatment beam constraint data and the treatment beam criteria data, the sub-sets being selected so that each of the targets being included in at least one of the subsets and the sub-treatment plans fulfilling the volume reduction criterion, in particular the criterion a) describing that, if projecting the at least two targets into a plane perpendicular to a spatially separate one of the one or more sub-beams and if projecting the cross sectional area of the spatially separate sub-beam into the plane, then there lies not more than one of the at least two projected spatially separate targets spatially separate, in particular by at least a predetermined distance, within the projected cross sectional area, in particular at least for not longer than a predetermined time for all the targets of the sub-set. 9. The method of claim 8, wherein the treatment beam criteria data comprise that all targets of each subset are treated at least sequentially and preferably simultaneously in accordance with the respective sub-treatment plan during a sub-treatment time interval. 10. The method of claim 9, wherein the sub-sets are determined based on candidate sub-sets, and those one of the candidate sub-sets are selected as subset for which a sub-treatment plan can be determined which describes simultaneous treatment of all targets of the subset during the whole sub-treatment time while not violating the radiation reduction criterion. 11. The method of claim 1, wherein the candidate set is determined by omitting one or more of the at least two targets during a time interval during which a potential treatment plan violates the volume reduction criterion, in particular the criterion a) describing that, if projecting the at least two targets into a plane perpendicular to a spatially separate one of the one or more sub-beams and if projecting the cross sectional area of the spatially separate sub-beam into the plane, then there lies not more than one of the at least two projected spatially separate targets spatially separate, in particular by at least a predetermined distance, within the projected cross sectional area, in particular at least for not longer than a predetermined time, the potential treatment plan fulfilling the condition that all of the at least two targets are simultaneously treated all over the treatment time, the time interval being referred to as violation time interval, and by including the omitted one or more of the at least two targets into the candidate set during a time interval outside the violation time interval and inside the treatment time, wherein the treatment device comprises a beam source to issue the at least one treatment beam and wherein there is a path of movement of the beam source relative to the at least two targets referred to as treatment path, which is in particular a preferably arc-shaped relative movement of the beam source in at least one vertical plane relative to the at least two targets, the sub-treatment plans describing treatment during movement of the beam source along the treatment path and/or a section of the treatment path, a) wherein there is more than one complete movement of the beam source along the treatment path between a starting point and an end point and wherein the treatment of each of the subsets is respectively assigned to one of the complete movements so that by performing more than one complete movement all targets are treated, and in particular wherein the treatment plan is determined so that the treatment path is only changed by rotating the patient in a reference system in which the treatment device is at rest, in particular by rotating the plane, if and after all of the at least two targets have been treated,b) wherein targets omitted according to one of the sub-treatment plans during forward movement of the beam source along a first subsection of the treatment path are treated according to another sub-treatment plan during backward movement or during another forward movement along a second subsection of the treatment path which first subsection can be identical; and/orc) wherein targets omitted according to one of the sub-treatment plans during movement of the beam source along a first subsection of a first treatment path are treated according to another sub-treatment plan during movement along a second subsection of a second treatment path, wherein the first treatment path and the second treatment path are in particular different due to a movement of the patient in a reference system in which the treatment device is at rest, in particular by rotating the at least two targets relative to the vertical plane, wherein in particular the first and second subsection would be identical without the movement of the patient in the reference system. 12. The method according to claim 1, wherein the treatment plan which describes simultaneous treatment and which is used for the definition of the radiation reduction criterion is a treatment plan which has been determined by minimizing the healthy volume which is subjected to treatment radiation. 13. A computer program embodied on a non-transitory computer readable medium which, when running on a computer or when loaded onto a computer, causes the computer to acquiring target data describing spatial information on the at least two spatially separate targets in a patient's body;acquiring treatment beam constraint data which allow determination of potential treatment plans which can be realized by the treatment device and which potential treatment plans describe potential arrangements of the at least one treatment beam, referred to as potential treatment beam arrangements;acquiring treatment beam criteria data describing criteria for the treatment of the at least two targets by the at least one treatment beam, the criteria comprising a radiation reduction criterion which describes that a treatment plan is allowed to be determined which describes a non-simultaneous treatment of the at least two targets at least for a time interval during the treatment time if this treatment plan describes that parts of the patient's body outside the at least two targets are less exposed to treatment radiation, in particular at least to a predetermined extent, compared to the case of a treatment plan which describes a simultaneous treatment of the at least two targets during the treatment time; anddetermining the treatment plan which fulfils the radiation reduction criterion based on the target data, the treatment beam constraint data and the treatment beam criteria data. 14. A radiation therapy system, comprising: a computer including the computer program of claim 13, wherein the computer program is executed on the computer or loaded onto the computer;a couch for placing a patient;and a treatment device comprising the beam shaping device and the beam source. 15. The radiation therapy system of claim 14, wherein the treatment device and the couch are movable relatively to each other, particularly wherein the couch is rotatable in a horizontal plane and/or the treatment device is movable along an arc-shaped pathway lying in a specifically vertically oriented plane.