Method and system for assisting positioning of patient

Abstract

The invention relates to a method for assisting the positioning of a patient in a treatment room for irradiation by means of an irradiation device, comprising the following steps: detecting a current surface of the body of the patient in the treatment room by means of a 3D surface detection system, calculating the intersection of the at least two lines with at least one isocenter of the detected surface of the patient's body showing the irradiation instrument, calculating the required transformation by means of a reference surface of the patient's body giving a theoretical position of the patient's body relative to the isocenter of the irradiation instrument, the method comprises the following steps:-calculating a transformation between the detected surface of the patient body and the reference surface in order to bring the detected surface of the patient body into conformity with the reference surface,-determining a target position of an intersection with the at least one isocenter of the detected surface of the patient body showing the irradiation instrument based on the calculated transformation,-in a visualization system,-determining the target position of the intersection with the at least one isocenter of the detected surface of the patient body. A point of intersection with the at least one of the detected surfaces of the patient's body displays an isocenter of the illumination instrument and a target position of the point of intersection are displayed. The invention further relates to a corresponding system.

Description

Technical Field

[0001] The present invention relates to a method and a system for assisting the positioning of a patient in a treatment room for irradiation with an irradiation apparatus. In radiation therapy, for example, a tumor is irradiated with such an irradiation apparatus. As an irradiation apparatus, a linear accelerator (Linac) is mainly used. An important aspect in radiation therapy is the precise positioning of the patient so that the radiation dose generated by the irradiation apparatus is incident as accurately as possible on the body tissue to be treated. Background Art

[0002] Patient positioning by means of lasers and markings on the patient's skin is known. Such a system is known, for example, from DE19524951A1. Laser systems for projecting laser planes, especially coronal, transverse and sagittal planes, for patient positioning are present, for example, in diagnostic rooms including imaging instruments, such as CT scanners for CT simulation, and on irradiation instruments. For example, in the process of CT simulation and subsequent irradiation planning, the isocenter of the tumor to be treated in the patient's body is determined by imaging. This isocenter of the tumor should be placed in line with the isocenter of the irradiation instrument as accurately as possible in a separate treatment room at a later time. In order to make the isocenter position of the tumor visible from the outside on the patient's body, at least three mutually orthogonal laser planes are oriented in the diagnostic room including the imaging system so that their common intersection is in the isocenter of the tumor. For this orientation, the laser plane can be moved in space using a movable laser track and / or the patient on the patient couch can move in space. The projected laser plane is drawn as a line on the surface of the patient's body, wherein two laser lines form an intersection on the body surface respectively. In this way, for example, three intersection points formed by two of the three orthogonal laser planes can be displayed on the surface of the patient's body, for example on two opposite sides and on the upper side of the patient's body. The intersection points of the laser lines can be marked with the help of a pen or a marking portion applied to the skin. In subsequent irradiation in the treatment room, the isocenter of the irradiation device can be displayed on the surface of the patient's body again by means of three laser planes oriented orthogonally to each other through the intersection points of the three lines in space. In order to orient this isocenter of the irradiation device to the isocenter of the tumor, the patient can be moved or rotated in space, for example with the help of a movable patient couch, so that the intersection points formed by two of the orthogonal laser planes on the surface of the patient's body coincide with the previously applied marking portions. When all intersection points on the body surface are aligned with the previously applied marking portions, the patient positioning is completed and the irradiation can begin.

[0003] This method of patient positioning is simple to implement and intuitive for the user, since it is immediately apparent what patient movements are necessary in order to bring the laser line into line with the marking on the patient's surface and thereby place the patient in the desired position. A disadvantage of this method is that the patient must bear the marking on his body at least for the duration of the radiation therapy, usually for several weeks. There is the risk that the marking will wash off or become unrecognizable in another way and that positioning of the patient is no longer possible with sufficient accuracy. Changes in the patient's body during the radiation therapy, such as a reduction in weight or a change in rigidity or shape of the patient's body, are also not always recognized and taken into account with sufficient accuracy. Furthermore, only three selected points are used for positioning the patient, which should also be as accurate as possible outside the plane of the intersection points.

[0004] A 3D surface detection system is also known from the prior art, which allows the positioning of patients for radiotherapy without a marker on the body. For example, surface detection systems are described in US7348974B2, US7889906B2, US9028422B2, US2015 / 265852A1 or US2016 / 129283A1. In the surface detection system, the three-dimensional surface of the patient's body measured in real time is compared with the three-dimensional reference surface of the patient's body previously constructed in the scope of irradiation planning, for example, by means of CT simulation. Deviations are displayed in the three-dimensional visualization of the theoretical and actual surfaces. In addition, the values ​​of the required movement and rotation for the patient can be calculated, which must be used on the patient's position, whereby the theoretical and actual surfaces are consistent. With such a three-dimensional surface detection system, the aiming accuracy of patient positioning is often large, because it can be oriented not only along the line or intersection of the projection, but also by means of the entire surface or a partial area of ​​the surface. Of course, the explanation of the values ​​displayed by the system about the positioning of the patient is less intuitive and requires a longer familiarity and learning phase for the user. This may also lead to operating errors. Summary of the invention

[0005] Starting from the explained prior art, the object of the present invention is therefore to provide a method and a system of the type mentioned at the outset, with which the positioning of a patient for irradiation on an irradiation device is assisted in a simple and intuitive manner for the user and at the same time with the greatest possible accuracy.

[0006] The invention achieves this object by means of independent claims 1 and 13. Advantageous embodiments are apparent from the dependent claims, the description and the drawings.

[0007] The invention achieves the object of a method of the type mentioned at the outset by means of the following steps:

[0008] • preferably detecting the current surface of the patient's body using a 3D surface detection system in the treatment room,

[0009] • calculating the intersection of at least two lines with at least one of the detected surfaces of the patient's body showing the isocenter of the irradiation apparatus,

[0010] • calculating the necessary transformation with the aid of a reference surface of the patient's body which gives the theoretical position of the patient's body relative to the isocenter of the irradiation apparatus in order to bring the detected surface of the patient's body and the reference surface into correspondence,

[0011] • determining a target position of an intersection point with the isocenter of the at least one display irradiation apparatus of the detected surface of the patient's body based on the calculated transformation,

[0012] • In a visualization system, a point of intersection of the at least one displayed irradiation instrument with the detected surface of the patient's body and a target position of the point of intersection are displayed.

[0013] The invention further achieves this object by means of a system of the type mentioned at the outset, which system

[0014] • having a 3D surface detection system, which is designed to detect the current surface of the patient's body, preferably in a treatment room,

[0015] • having an evaluation device which is configured to calculate the intersection of at least two lines with at least one isocenter of the detected surface of the patient's body representing the irradiation device,

[0016] • wherein the evaluation device is further designed to calculate the necessary transformation with the aid of a reference surface of the patient's body which indicates a theoretical position of the patient's body relative to the isocenter of the irradiation device in order to bring the detected surface of the patient's body into correspondence with the reference surface,

[0017] • wherein the evaluation device is further designed to determine, based on the calculated transformation, a target position of a point of intersection with the at least one isocenter of the detected surface of the patient's body, which represents the irradiation device,

[0018] and having a visualization system which is designed to display, based on the calculated transformation, a point of intersection of the at least one display of the irradiation device with the detected surface of the patient's body and a target position of the point of intersection.

[0019] The irradiation device is used to irradiate a patient, for example for tumor treatment. The irradiation device can be a linear accelerator (Linac). According to the invention, the position of a patient, preferably in a treatment room, for example on a movable patient couch, is detected using a three-dimensional surface detection system. In particular, the detection of the three-dimensional surface of the patient's body is performed multiple times in succession, for example at fixed time intervals or continuously. The three-dimensional surface detection system can be constructed in a manner known per se. As known per se, the three-dimensional surface detection system can, for example, have a camera, in particular a stereoscopic camera system.

[0020] In the isocenter of the irradiation instrument, the radiation dose generated by the irradiation instrument is often the largest. The isocenter of the irradiation instrument should be as accurate as possible with the isocenter of the tissue to be irradiated, especially the tumor. For this purpose, the intersection of at least two lines or two planes on the patient's body surface is calculated according to the present invention. The intersection shows the isocenter of the irradiation instrument. The intersection is calculated by the intersection of the orthogonal planes intersecting in the isocenter of the irradiation instrument and the body surface. The isocenter, which is, for example, the intersection of three orthogonal planes, is usually located inside the patient's body positioned on the patient couch. The three orthogonal planes, for example, are therefore drawn on the patient's body as three lines, which intersect in pairs on the body surface, for example, on two opposite sides and the upper side of the body. That is, two of the three lines respectively show the isocenter with their intersection points with the body surface. These lines and their intersection points can be calculated and visualized according to the present invention. Correspondingly, three intersection points of each of the two lines with the detected surface of the patient's body can be calculated, i.e., the intersection points of the three orthogonal planes that intersect in the isocenter of the irradiation device at three locations on the surface of the patient's body. If, for example, the intersection points on the underside of the patient's body are also calculated, of course, more than three intersection points, for example four intersection points, can also be calculated and visualized on the body surface. Whenever lines and intersection points are mentioned here, this also includes (orthogonal) planes that are drawn as lines on the body surface.

[0021] In the present invention, a three-dimensional reference surface of the patient's body is also considered, which gives the theoretical position of the patient's body relative to the isocenter of the irradiation instrument. The reference surface is predetermined for the theoretical position of the irradiated patient's body. For example, the reference surface can be constructed within the scope of the irradiation planning before irradiation. For this purpose, the tissue to be irradiated, especially the tumor, can be determined using imaging methods, such as CT or MRT methods. Using a 3D surface detection system in a diagnostic room, for example, the surface of the patient's body can be detected and it can be calculated accordingly, how the surface must be oriented for subsequent irradiation with respect to the isocenter of the irradiation instrument. The 3D surface detection system in the diagnostic room can be constructed in principle in the same way as the 3D surface detection system in the treatment room.

[0022] Based on this or another reference surface constructed, for example, from data of an imaging method, a transformation of the current surface of the patient's body detected by a 3D surface detection system, in particular in the treatment room, is calculated in order to bring the current surface into correspondence with the reference surface, in particular in such a way that the isocenter of the irradiation device coincides with the center of the tissue of the patient's body to be irradiated. The transformation can, for example, include a required movement of the patient's body and / or the reference surface in all three spatial directions and / or a rotation about one or more rotation axes. The calculation of the transformation can be performed, for example, using an iterative method known per se, such as the iterative closest point method.

[0023] According to the invention, a target position of the intersection point with the at least one display irradiation device is determined based on the calculated transformation. In the visualization system, the intersection point with the at least one display irradiation device isocenter of the detected surface of the patient's body and its target position determined based on the transformation are displayed. Based on the transformation or the inverse transformation carried out on this basis, a target position in the patient's coordinate system is determined for the previously calculated intersection point, as it is drawn on the patient's body when the patient's body is oriented as specified to the isocenter of the irradiation device. The target position corresponds to at least one point on the reference surface of the patient's body in the patient's coordinate system. Based on the transformation or the inverse transformation calculated according to the invention, such a target position can be determined in principle for any point on the surface of the patient's body, that is, in particular, the intersection point of the display isocenter of the lines or orthogonal planes. Based on the display of the intersection point and the target position in the visualization system, the user can position the patient in a simple manner so that the intersection point and its target position coincide and the patient is oriented as specified to the isocenter of the irradiation device. The visualization system is software-based. The visualization system can be implemented, for example, on a PC, a laptop, a notebook computer, a tablet computer or the like. The visualization is correspondingly performed on a display of a corresponding device.

[0024] Whenever a surface or reference surface of the patient's body is mentioned here, this includes in principle the surface or reference surface of the entire patient's body or only a section of the patient's body, for example a section of the patient's body that is relevant for the irradiation. It should be further stated that the method according to the invention is preferably carried out in a treatment room using an irradiation device, or the system according to the invention is preferably located in a treatment room. However, this is not mandatory. Thus, it is also possible, additionally or alternatively, to carry out the method in another room or to locate the system in another room, for example, in a diagnostic room. For example, the method according to the invention can already be carried out in a diagnostic room before the patient is positioned in the treatment room.

[0025] The present invention is therefore based on the idea that virtual markings and virtual positioning lasers on the detected surface of the patient's body are calculated with the help of the currently detected three-dimensional surface of the patient's body and the transformation of the patient's body calculated with the help of the three-dimensional reference surface and are displayed to the user. Patient positioning based on virtual markings and virtual positioning lasers can be implemented particularly intuitively and simply. At the same time, the advantages of high-precision surface detection and the transformation determined thereby are utilized. In this way, the accuracy of a 3D surface detection system is achieved in a simple and intuitive operation, as in the case of conventional markings on the body surface and corresponding positioning lasers. The advantages of the two systems are combined without incurring the corresponding disadvantages. By the preferably continuous calculation and display of the at least one intersection point and its target position on the body surface, it is possible for the user to visualize in a simple way what degrees of freedom and direction the patient must move in order for the at least one intersection point to be consistent with its target position.

[0026] The method according to the invention, in particular its steps, can be carried out several times in succession, for example at fixed time intervals or preferably continuously. In this way, a continuous real-time monitoring of the patient's position and the necessary repositioning of the patient for irradiation can be displayed in the visualization system and controlled by the user. The user can thus continuously approach and / or monitor the correct patient position in a simple manner.

[0027] In order to facilitate positioning, the at least one intersection point and its target position can be displayed in a visualization system as an intersection of lines.

[0028] According to one design, a patient couch supporting the patient's body and / or a patient on the patient couch can be moved in the treatment room in such a way that the intersection point with the detected surface of the patient's body, which shows the isocenter of the irradiation device, coincides with the target position of the intersection point. The positioning can be performed automatically or manually controlled. For this purpose, the patient's body can be located on a movable patient couch, which can be moved, for example, in three mutually perpendicular directions and can also be rotated about one or more rotation axes, for example a vertical rotation axis and a rotation axis in the longitudinal direction and / or in the transverse direction of the patient couch. The user can thereby position the patient couch or the patient in such a way that the marking portion of the isocenter of the irradiation device coincides with the target position of the marking portion in the visualization system.

[0029] According to another design, it can be arranged that the intersection points of at least three lines with at least three isocenters of the detected surface of the patient's body showing the irradiation device are calculated and displayed in the visualization system, and at least three target positions determined based on the calculated transformation with the intersection points of the at least three isocenters of the detected surface of the patient's body showing the irradiation device are displayed in the visualization system. As already explained, the isocenter of the irradiation device can be defined by the intersection of three orthogonal planes, especially in the treatment room. Since the isocenter is usually located inside the patient's body, two of the orthogonal planes respectively form an intersection point on the surface of the patient's body as lines imaged on the body surface, wherein a total of three intersection points are formed by the three orthogonal planes, for example on the opposite sides of the patient's body and on the upper side of the patient's body. These intersection points can be calculated and displayed in the visualization system according to the above-mentioned design. Correspondingly, based on the transformation calculated according to the present invention, the target positions of these intersection points are also calculated and displayed in the visualization system in the manner explained above. The positioning of the patient's body is further improved by this embodiment in that all intersection points must be brought into correspondence with their target position by a corresponding displacement movement of the patient couch and / or a movement of the patient's body on the patient couch.

[0030] According to another particularly practical embodiment, the detected surface of the patient's body can also be displayed in the visualization system, wherein intersection points with the at least one displayed isocenter of the detected surface of the patient's body and the target position of the intersection point are displayed on the surface of the patient's body displayed in the visualization system. The same applies, of course, to other intersection points, if necessary. The joint display of the patient's body with the intersection points on its surface and the corresponding target positions further simplifies the visualization and thereby the positioning of the patient for the user.

[0031] According to another embodiment, at least two lines defining the intersection of the at least one isocenter displaying the irradiation device can also be displayed in the visualization system. The target position of the intersection of the at least one isocenter displaying the irradiation device can also be displayed in the visualization system via the intersection of the at least two lines. In particular, the lines can be displayed on a currently detected patient surface that is also displayed in the visualization system. By displaying and orienting the lines during the patient positioning, the positioning accuracy is further improved in that, in particular, longer lines that can extend over the entire length and / or width of the patient's body must be aligned. Thus, a complete virtual simulation of the patient positioning described above in the prior art is performed essentially by means of projected orthogonal laser planes and their intersections with the patient surface that are displayed as lines on the patient surface.

[0032] According to another embodiment, a reference surface of the patient's body can be constructed within the scope of the irradiation planning before the positioning of the patient. The construction of the reference surface can be carried out in particular in a diagnosis room separated from the treatment room. The diagnosis room can have an imaging system, such as a CT or MRT system, in a manner known per se. The patient's body is detected together with the tissue to be irradiated, such as a tumor. Based on this, the reference surface can be constructed in a manner known per se.

[0033] According to another design, in addition to the intersection of the isocenter of the irradiation device, other intersections with the detected surface of the patient's body can be calculated. The other intersections can then be displayed in the visualization system together with the target position determined based on the calculated transformation. By using other intersections, such as virtual markings and orientations of prominent points on the body surface, such as hip bones, skulls, noses, feet, knee joints, etc., the positioning of the patient in space can be further improved. Similar to the human body model, for example, points can be marked on the surface, such as in the abdominal area or the like, which make the movement of the patient's body or the deformation of the patient's body visible. In particular, changes in body shape can be seen in this way, for example, when the rigidity of the patient's body changes. This is not always reliably recognized, for example, when there is only a marking of the isocenter. The other intersections can also be the intersection of two lines or two orthogonal planes. Again, the lines defining the other intersections can also be shown on the body surface in the visualization system. Because the surface of the patient's body is detected according to the present invention and the transformation is calculated for this surface, in principle, any point can be marked and displayed on the body surface. In practice, a suitable compromise is chosen here between, on the one hand, the number of points to be displayed and thereby brought into line by the displacement of the patient couch and / or the movement of the patient's body on the patient couch and, on the other hand, the required positioning accuracy.

[0034] In order to further improve the patient's positioning, the other intersection point can be, for example, an intersection point with an edge region of the patient's surface, for example, at the opposite end of the patient's body. By having to place the markings that are far apart from each other in agreement with their respective target positions, particularly accurate positioning is possible.

[0035] According to another embodiment, the at least one intersection point and its target position can be displayed in the visualization system from different viewing angles. This further facilitates positioning. For example, the display can be performed from opposite sides of the patient's body and from the upper side of the patient's body. This applies to the three-dimensional surface of the patient's body, as long as this three-dimensional surface is also displayed in the visualization system.

[0036] According to another design, the target position of the intersection with the at least one isocenter of the detected surface of the patient's body, which displays the irradiation device, can be checked by means of a line laser or a cross laser arranged in the treatment room and / or the diagnosis room. In this design, a physical laser arranged in the treatment room or the diagnosis room, which projects orthogonal laser planes in space, is used to define the position of the virtual laser marking. For this purpose, the current position of the physical laser in the treatment room or the diagnosis room can be detected and transmitted to the virtual surface data of the system according to the invention.

[0037] According to another embodiment, at least one further target position of at least one further intersection point with the surface of the patient's body can be determined, and the at least one further intersection point with the detected surface of the patient's body and its further target position can be displayed in the visualization system. In this way, further virtual intersection points with the detected surface of the patient's body can be determined and accepted as target positions.

[0038] According to another design, the position of the intersection point can be displayed on the detected surface of the patient's body by means of a line laser or a cross laser arranged in the treatment room and / or the diagnosis room, and the displayed position is determined as the target position or as another target position and displayed in the visualization system. That is, other intersection points with the detected surface of the patient's body can be displayed by a physical line laser or a cross laser and read by the system according to the invention. These other intersection points can then be accepted as (other) target positions. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Next, the embodiments of the present invention will be further explained with the aid of the accompanying drawings. Schematically:

[0040] Figure 1 shows a perspective view of a system according to the present invention;

[0041] Figure 2 A diagram showing a visualization system of the system according to the invention in a first operating state;

[0042] Figure 3 In the second operating state Figure 2 ; and

[0043] Figure 4 In the third operating state Figure 2 . DETAILED DESCRIPTION

[0044] Unless otherwise indicated, identical reference numerals denote identical objects in the figures.

[0045] exist Figure 1 In the figure, the system according to the invention is shown in a treatment room including an irradiation device 10, which can be, for example, a linear accelerator (Linac) for tumor treatment. The patient's body 12 is located on a patient couch 14 that is movable in the treatment room and can be moved, for example, in three spatial directions and rotatable about a vertical axis. Rotatability of the patient couch 14 about its longitudinal axis and / or transverse axis can also be realized. The irradiation device 10 can be rotated around the patient's body 12 during irradiation in a manner known per se.

[0046] The system further comprises a 3D surface detection system comprising two stereoscopic cameras 16 in the example shown. The current three-dimensional surface of the patient's body 12 in the treatment room is detected using the cameras 16. This can be done multiple times in succession, in particular continuously. The detected surface of the patient's body 12 is shown in the visualization system 18 of the system according to the invention, as explained in more detail below.

[0047] In addition, three line lasers or cross lasers 20 are arranged in the treatment room, which project at least three mutually orthogonal laser planes 22 in space, which intersect in the isocenter 24 of the irradiation device 10. The isocenter 24 is usually located inside the patient's body 12. The laser planes 22 projected by the line lasers or cross lasers 20 are imaged on the surface of the patient's body 12 in a corresponding linear manner, wherein two laser lines imaged on the body surface respectively form an intersection point on the surface of the patient's body 12. For example, three intersection points can be formed on the surface of the patient's body, namely on opposite sides of the patient's body 12, on the other side of the patient's body 12, on the other side of the patient's body 12. Figure 1 On the left and right sides and on the upper side of the patient's body 12.

[0048] The system according to the invention furthermore has an evaluation device 26 which, independently of the line laser or cross laser 20 physically present in the treatment room, calculates the intersection points of at least two lines, respectively, corresponding to the plane of projection of the physical line laser or cross laser 20, with the isocenter 24 of the surface of the patient's body 12 detected by the 3D surface detection system, in particular the camera 16, which represents the irradiation device 10. For example, in the scope of irradiation planning before the irradiation, an imaging system such as a CT or MRT system is used to construct a three-dimensional reference surface of the patient's body, which specifies the theoretical position of the patient's body 12 with respect to the isocenter 24 of the irradiation device 10. With the aid of this reference surface, the evaluation device 26 calculates the necessary transformation in order to bring the surface of the patient's body 12 detected by the 3D surface detection system into correspondence with the reference surface. Based on the calculated transformation, the target position of the intersection point with the isocenter 24 of the surface of the patient's body 12, which represents the irradiation device 10, is again determined by the evaluation device 26. The target position of the patient's body 12 is usually such that the isocenter of the tissue to be treated, in particular the tumor to be irradiated, coincides with the isocenter 24 of the irradiation device 10 .

[0049] In the visualization system 18, the intersection point of the isocenter 24 of the irradiation device 10 with the detected surface of the patient's body 12 and the corresponding target position of the intersection point are displayed. Figures 2 to 4 Further explanation.

[0050] exist Figure 2 A situation is shown in which the patient body 12 is not yet correctly oriented. In the example shown, in addition to the detected patient body 12, lines 28 are also displayed in the visualization system 18, which define the intersection point of the isocenter of the display irradiation instrument. Figure 2 In the embodiment, the intersection point 30 is defined by the line 28 as an intersection point formed on the upper side of the patient's body 12. Further intersection points are usually formed on the opposite side of the patient's body. Figure 2 As can be seen in FIG. 1 , the target position 32 of the intersection point 30 is also displayed in the visualization system 18 , namely also as the intersection point 32 of two lines 34 , namely the sighting lines 34 . Figure 2 It can be seen that the patient's body has not yet been correctly positioned for irradiation. It can be seen that the intersection point 30 and its target position 32 and the lines 28, 34 defining it are not yet in agreement.

[0051] exist Figure 3 In particular, the patient body 12 and / or the patient couch 14 are rotated about a vertical axis of rotation so that the position between the lines 28 and 34 is eliminated. Figure 2The lines 28, 34 extending in the longitudinal direction are already oriented to each other. There is also a distance between the lines 28, 34 extending transversely to the longitudinal direction of the patient's body 12, which also exists between the intersection point 30 and the target position 32.

[0052] exist Figure 4 This distance is also eliminated in that the patient body 12 is displaced in the longitudinal direction by a corresponding displacement of the patient couch 14 and / or a movement of the patient body on the patient couch 14 such that all lines 28 , 34 and thereby the intersection point 30 and the target position 32 now coincide.

[0053] In a corresponding manner, the further intersection points of the lines defining the isocenter 24 of the irradiation device 10 are aligned for complete positioning of the patient body 12. The patient positioning is completed and the irradiation can take place.

[0054] It is also possible to calculate and display further intersection points of the corresponding lines on the surface of the patient's body 12. In this way, the positioning accuracy can be further improved. In the visualization system 18, the patient's body 12 can be displayed with the intersection points 30, 32 and the lines 28, 34 from different viewing angles, in order to simplify the orientation of all intersection points.

[0055] If desired, the orientation of the calculated lines 28 , 34 shown in the visualization system 18 can be checked with the aid of a physical line laser or cross laser 20 provided in the treatment room. Reference numerals list

[0056] 10 Irradiation equipment

[0057] 12 Patient Body

[0058] 14 Patient recliner

[0059] 16 Camera

[0060] 18 Visualization System

[0061] 20-line laser or cross laser

[0062] 22 Laser plane

[0063] 24 Isocenter of the irradiation instrument

[0064] 26Evaluation Equipment

[0065] Line 28, 34

[0066] 30 intersections

[0067] 32 Target position of intersection

Claims

1. A method for assisting the positioning of a patient in a treatment room for irradiation with an irradiation device (10), the method comprising the steps of: • detecting the current surface of the patient's body (12) using a 3D surface detection system (16), • calculating the intersection (30) of at least two lines (28) with at least one isocenter (24) of the detected surface of the patient's body (12) showing the irradiation device (10), • calculating the required transformation with the aid of a reference surface of the patient's body (12) which gives the theoretical position of the patient's body (12) relative to the isocenter (24) of the irradiation device (10) in order to bring the detected surface of the patient's body (12) into correspondence with the reference surface, • determining, based on the calculated transformation, a target position (32) of an intersection point (30) with the at least one detected surface of the patient's body (12) showing the isocenter (24) of the irradiation device (10), • In the visualization system (18), an intersection point (30) of the at least one display irradiation device (10) with the detected surface of the patient's body (12) and a target position (32) of the intersection point are displayed.

2. The method according to claim 1, characterized in that A patient couch (14) supporting the patient's body (12) and / or a patient on the patient couch (14) is moved in the treatment room so that an intersection point (30) of at least one detected surface of the patient's body (12) showing the isocenter (24) of the irradiation device (10) coincides with a target position (32) of the intersection point.

3. The method according to any one of the preceding claims, characterized in that The intersection points (30) of at least three lines (28) with at least three detected surfaces of the patient's body (12) showing the isocenter (24) of the irradiation device (10) are calculated and displayed in the visualization system (18), and at least three target positions (32) determined based on the calculated transformation are displayed in the visualization system (18) with the at least three detected surfaces of the patient's body (12) showing the isocenter (24) of the irradiation device (10).

4. The method according to any one of the preceding claims, characterized in that The detected surface of the patient's body (12) is also displayed in the visualization system (18), wherein an intersection point (30) of at least one of the detected surfaces of the patient's body (12) and an isocenter (24) of the irradiation device (10) and a target position (32) of the intersection point are displayed on the surface of the patient's body (12) displayed in the visualization system (18).

5. The method according to any one of the preceding claims, characterized in that The at least two lines (28) defining the intersection point (30) of the at least one isocenter (24) displaying the irradiation device (10) are displayed in the visualization system (18), and the target position (32) of the at least one intersection point (30) displaying the isocenter (24) of the irradiation device (10) is also displayed in the visualization system (18) by at least two lines (34).

6. The method according to any one of the preceding claims, characterized in that A reference surface of the patient's body (12) is constructed within the scope of irradiation planning prior to positioning the patient (12) in the treatment room.

7. The method according to any one of the preceding claims, characterized in that A further intersection point (30) with the detected surface of the patient's body (12) is calculated, and the further intersection point (30) and a target position (32) of the further intersection point (30) determined based on the calculated transformation are displayed in the visualization system (18).

8. The method according to claim 7, characterized in that The further intersection point (30) is the intersection point with the edge region of the patient's surface.

9. The method according to any one of the preceding claims, characterized in that The at least one intersection point (30) and a target position (32) of the intersection point are displayed in the visualization system (18) from different viewing angles.

10. The method according to any one of the preceding claims, characterized in that A target position (32) of an intersection point (30) with at least one isocenter (24) of the detected surface of the patient's body (12) displaying the irradiation device (10) is checked by means of a line laser or a cross laser (20) arranged in the treatment room and / or the diagnosis room.

11. The method according to any one of the preceding claims, characterized in that At least one further target position of at least one further intersection point with the surface of the patient's body (12) is determined, and the at least one further intersection point with the detected surface of the patient's body (12) and the further target position of the further intersection point are displayed in the visualization system (18).

12. The method according to any one of the preceding claims, characterized in that Using a line laser or a cross laser (20) arranged in the treatment room and / or the diagnosis room, the position of the intersection is displayed on the detected surface of the patient's body (12), and the displayed position is determined as a target position or as another target position and is displayed in the visualization system (18).

13. System for assisting the positioning of a patient in a treatment room for irradiation with an irradiation apparatus (10), • having a 3D surface detection system, which is configured to detect the current surface of the patient's body (12), • an evaluation device (26) which is designed to calculate the intersection point (30) of at least two lines (28) with at least one isocenter (24) of the detected surface of the patient's body (12) representing the irradiation device (10), •in, The evaluation device (26) is further designed to calculate the required transformation with the aid of a reference surface of the patient's body (12) which indicates a theoretical position of the patient's body (12) relative to the isocenter of the irradiation device (10) in order to bring the detected surface of the patient's body (12) and the reference surface into correspondence, • wherein the evaluation device (26) is further configured to determine a target position (32) of an intersection point (30) with the at least one detected surface of the patient's body (12) showing the isocenter (24) of the irradiation device (10) based on the calculated transformation, • and having a visualization system (18) configured to display an intersection point (30) of the isocenter (24) of the irradiation instrument (10) with at least one of the detected surfaces of the patient's body (12) based on the calculated transformation and a target position (32) of the intersection point.

14. The system according to claim 13, characterized in that The system further comprises a patient couch (14) for supporting the patient's body (12), the patient couch being movable in the treatment room so that an intersection point (30) with at least one detected surface of the patient's body (12) showing the isocenter (24) of the irradiation device (10) and a target position (32) of the intersection point can be brought into correspondence.

15. The system according to claim 13 or 14, characterized in that The evaluation device (26) and the visualization system (18) are designed to calculate and display in the visualization system (18) at least three intersection points (30) of the at least three lines (28) with at least three isocenters (24) of the detected surface of the patient's body (12) showing the irradiation device (10), and the visualization system (18) is further designed to display at least three target positions (32) determined based on the calculated transformation with the at least three intersection points (30) of the detected surface of the patient's body (12) showing the isocenters (24) of the irradiation device (10).

16. System according to any one of claims 13 to 15, characterized in that The visualization system (18) is further configured to display the detected surface of the patient's body (12) and to display, on the surface of the patient's body (12) displayed in the visualization system (18), an intersection point (30) of at least one display of the isocenter (24) of the irradiation device (10) and a target position (32) of the intersection point with the detected surface of the patient's body (12).

17. The system according to any one of claims 13 to 16, characterized in that The visualization system (18) is further designed to display the at least two lines (28) defining the intersection point (30) of the isocenter (24) of the at least one display irradiation device (10), and also to display a target position (32) of the intersection point (30, 32) of the isocenter (24) of the at least one display irradiation device (10) via at least two lines (34).

18. The system according to any one of claims 13 to 17, characterized in that The system further comprises an irradiation planning system which is designed to construct a reference surface of the patient's body (12) within the scope of irradiation planning prior to positioning of the patient (12) in a treatment room.

19. The system according to any one of claims 13 to 18, characterized in that The evaluation device (26) is further configured to calculate further intersection points (30) with the detected surface of the patient's body (12), and the visualization system (18) is further configured to display the further intersection points (30) and target positions (32) of the further intersection points (30) determined based on the calculated transformation.

20. The system according to claim 19, characterized in that The further intersection point (30) is the intersection point with the edge region of the patient's surface.

21. The system according to any one of claims 13 to 20, characterized in that The visualization system (18) is designed to display the at least one intersection point (30) and the target position (32) of the at least one intersection point from different viewing angles.

22. The system according to any one of claims 13 to 21, characterized in that The system also has a line laser or a cross laser (20) arranged in the treatment room, and the evaluation device (26) is further designed to check a target position of an intersection point (30) with an isocenter (24) of the at least one display irradiation device (10) of the detected surface of the patient's body (12) by means of the line laser or the cross laser (20) arranged in the treatment room and / or the diagnosis room.

23. The system according to any one of claims 13 to 22, characterized in that The evaluation device (26) is further configured to determine at least one further target position of at least one further intersection point with the surface of the patient's body (12), and the visualization system (18) is further configured to display the at least one further intersection point with the detected surface of the patient's body (12) and the further target position of the further intersection point.

24. The system according to any one of claims 13 to 23, characterized in that The system further comprises a line laser or a cross laser (20) arranged in the treatment room, which is designed to display the position of an intersection on the detected surface of the patient's body (12), and the evaluation device (26) is further designed to determine the displayed position as a target position or as a further target position, and the visualization system (18) is further designed to display the target position or the further target position.

Images