Optical arrangement for an x-ray system for determining patient position and / or patient rotation

Abstract

The invention relates to an optical device for an X-ray system, to an X-ray system comprising such an optical device, to a system for controlling a patient position and / or a patient rotation and to a method for determining a patient position and / or a patient rotation, the optical device being for determining a patient position and / or a patient rotation of a patient to be X-ray irradiated by the X-ray system. The optical device comprises a laser source and a detector vertically spaced apart from each other. The laser source is configured to emit a horizontal laser line onto the patient, the detector is configured to detect a course of the laser line emitted onto the patient. An analysis unit is configured to determine the patient position and / or the patient rotation of the patient based on an analysis of the detected course of the laser line. The analysis unit is configured to verify whether the determined patient position and / or patient rotation of the patient corresponds to a predetermined reference parameter, and wherein the analysis unit is configured to generate a feedback signal based on a result of the verification.

Description

TECHNICAL FIELD

[0001] The present invention relates to the field of optical devices for X-ray systems for determining patient position and / or patient rotation and more specifically to an optical device for a chest X-ray system, an X-ray system for generating an X-ray image and a method for determining patient position and / or patient rotation. BACKGROUND

[0002] X-ray is a widely used diagnostic imaging modality for diagnosing diseases in the thoracic region, in particular the lungs. The assessment of X-ray quality, in particular chest radiograph quality, is an important step in radiological interpretation. In the current workflow, quality issues can only be detected during radiological image interpretation, which means after the generation of the X-ray image. This leads to patient recalls and re-takes of the X-ray image. Manual observation by medical staff during the X-ray imaging process can not be sufficient to prevent quality loss of the X-ray image. Furthermore, patient recalls put an additional burden on the medical staff, the technician and the patient himself, who has to go through additional exposure. The reasons for patient recalls and re-takes of the X-ray image are wrong patient orientation and patient movement, for example due to inhalation during the imaging process, which leads to errors in the field of view, which is the size of the exact anatomical region included in the image. Due to incorrect patient positioning and patient movement, the field of view is impaired. At the same time, if the patient is not oriented properly for X-ray imaging, the X-ray image does not meet the quality standards, as there can be shadows mediastinum and other segments on the region of interest (ROI). The other aspect is patient movement caused by patient inhalation. Properly holding breath during the X-ray imaging procedure can help to image the patient's heart and lungs more clearly. In contrast, it can happen multiple times that the patient inhales incorrectly or the patient's health condition does not support holding breath properly for a longer time. In this case, the medical staff cannot obtain information about this before triggering the X-ray image. Once the X-ray image can be generated, then only the medical staff or the technician or the radiologist can find out that the inhalation was wrong and has to ask for a re-take. SUMMARY

[0003] Therefore, there is a need to optimize the quality of the X-ray image. In particular, there is a need to improve the identification of patient orientation, in particular patient position and patient rotation, and patient movement due to inhalation in order to improve the quality of the X-ray image so that patient recalls and re-takes of the X-ray image can be avoided.

[0004] It is an object of the present invention to provide a device and a method for evaluating patient position, patient rotation and patient inhalation in real time and autonomously triggering an X-ray when the position, rotation and / or inhalation is correct.

[0005] The objects of the present invention are solved with the subject matter of the independent claims, wherein further embodiments are incorporated in the dependent claims.

[0006] According to a first aspect of the present invention, an optical arrangement comprises a laser source and a detector, the optical arrangement to be used with an X-ray system for determining a patient position and / or a patient rotation of a patient to be X-ray irradiated by the X-ray system. As will become apparent from the present disclosure, when the proposed optical arrangement is applied to its intended purpose and when applied with an X-ray system for determining a patient position and / or a patient rotation of a patient, the detector is vertically spaced apart from the laser source. The laser source is configured to emit a horizontal laser line onto the patient, wherein the detector is configured to detect a course of the laser line emitted onto the patient. An analysis unit is configured to determine the patient position and / or the patient rotation of the patient based on an analysis of the detected course of the laser line. The analysis unit is further configured to verify whether the determined patient position and / or patient rotation of the patient corresponds to a predetermined reference parameter, and wherein the analysis unit is configured to generate a feedback signal based on a result of the verification.

[0007] In the context of the present invention, the term "patient position" is to be understood as describing a position of a patient to be X-ray irradiated by an X-ray system, wherein the position refers to a position of the patient in front of an X-ray sensor. As understood by the skilled person, the position can be described / defined by e.g. 3D coordinates. During X-ray imaging, a predetermined portion of the patient, i.e. a body portion, e.g. the chest or back of the patient, shall be examined. Thus, the patient position is related to the quality of the generated X-ray image. For example, the patient can be positioned too close to one side or the other side of the X-ray sensor, which would result in a loss of information in the generated X-ray image. Thus, a correct patient position can be e.g. that the centerline of the patient is symmetrically aligned with the centerline of the X-ray sensor. This will be explained in more detail in the context of specific embodiments below.

[0008] In the context of the present invention, the term "patient rotation" is to be understood as describing a rotation of the patient in front of the X-ray sensor, which corresponds to the patient position, which can reduce the quality of the generated X-ray image. The patient rotation can describe / define a rotational state of the patient within a 3D space. For example, the patient can be rotated to the left or right side in front of the X-ray sensor, which can result in a loss of image information, as the patient is not standing correctly in front of the X-ray sensor. An ideal position of the patient can be a position of the patient, wherein a centerline extending from the head through the center of the patient to the feet is aligned with a centerline of the X-ray sensor, the centerline extending vertically from the top to the bottom of the X-ray sensor.

[0009] In the context of the present invention, the term "horizontal laser channel" is to be understood as describing the position and course of the laser line within the real setup of the optical device. As understood by the person skilled in the art, the horizontal line extends in 3D space parallel to the horizontal line and / or parallel to the ground plane on which the optical device is located, preferably used and applied together with the X-ray system. This will be explained in more detail in the context of specific embodiments, especially the embodiments shown in the attached drawings, below. The laser line is emitted onto the patient, wherein the laser line extends horizontally above the patient from the left side of the patient to the right side of the patient or vice versa. In particular, the horizontal laser line extends perpendicular to the center line of the patient. Typically, the position of the laser line is located at the chest or back of the patient, wherein the exact position is determined by the medical staff, technician and / or radiologist prior to triggering the X-ray image. The exact position can depend on the respective body part to be examined, whether it is the lungs, heart, etc. of the patient. In particular, the horizontal laser line is emitted onto the body surface of the patient, wherein the detector detects the course of the laser line on the body surface of the patient.

[0010] In the context of the present invention, the term "course of the laser line" is to be understood as describing the extension, spatial development and / or spatial course of the laser line along its horizontal extension. The course of the laser line can be understood as a curvature of the laser line, wherein the curvature can be straight along the horizontal extension. On the other hand, the curvature can be circular or curved in a different shape, wherein the shape depends on the object or source (e.g. the patient body surface) onto which the horizontal laser line is emitted. Further, the course of the laser line can comprise gaps, or the laser line can be interrupted. In particular, the course of the laser line can be the course in front of the X-ray sensor with and / or without the patient. For example, in the case without the patient, the laser line is emitted onto the X-ray sensor instead of the patient, wherein in the case with the patient, the laser line is emitted onto the patient in front of the X-ray sensor. In particular, the course of the laser line without the patient can be a straight horizontal line, wherein the course of the laser line emitted onto the patient is a curved horizontal line due to the presence of / based on the shape of the body surface of the patient.

[0011] In the context of the present invention, the term "vertically spaced apart" is to be understood as describing the arrangement of the laser source and the detector relative to each other. The laser source and the detector can be arranged one above the other, wherein the laser source can be arranged above the detector or vice versa. The spaced apart arrangement of the laser source and the detector is vertical, i.e. perpendicular to the horizontally extending laser line, when the laser line is horizontally extending. The vertical arrangement of the laser source and the detector can be parallel to the center line of the patient. This will be explained in more detail in the context of specific embodiments, especially the embodiments shown in the attached drawings, below.

[0012] In other words, with the optical device presented herein, a laser-based optical telemetering solution for detecting and determining a patient position and / or a patient rotation and / or for providing feedback is provided. The feedback provided can be used to correct and evaluate a patient position and a patient rotation, which will be described in detail below and in connection with some embodiments. The same laser-based method can be used to determine a patient position and a patient rotation. A detector detects the reflected radiation, i.e. the laser line, on the patient. The detector of the optical device can be vertically spaced from the laser source in such a way that the detector can be arranged above the laser source in the X-ray room in which the patient is imaged, or vice versa. In particular, the positions of the laser source and the detector are interchangeable. When the detector and the laser source are spaced apart from each other, a change in the emitted laser line due to the presence of the patient can become visible. In contrast, if the detector and the laser source are not spaced apart, i.e. are not distanced from each other, for example if they would be arranged at the same height, the detector cannot detect a change in the course of the laser line. The distance between the patient and the laser source can depend on the respective settings of the X-ray system and can be selected accordingly by a user and using the present disclosure.

[0013] The settings can be fixed and depend on the fixed positions of the X-ray sensor and the X-ray source. The preferred distance between the X-ray source and the X-ray sensor can be in the range of 1.5 m to 2 m. The laser line can be placed on the chest of the patient for an anterior-posterior (AP) X-ray imaging and / or the laser line can be placed on the back of the patient for a posterior-anterior (PA) X-ray imaging. According to this embodiment, the patient position and the patient rotation can be determined before triggering the X-ray image, so that it can be determined whether the patient is correctly oriented in front of the X-ray sensor. Thus, the quality of the generated X-ray image can be evaluated and positively influenced before the X-ray image is generated, which reduces the recall of patients, the re-shooting of X-ray imaging and the exposure of patients to X-ray radiation.

[0014] A feedback signal can be provided to a user by means of an embodiment of the present optical device, so that the position and / or rotation of the patient can be evaluated and the user can determine based on the feedback signal whether the position and / or rotation of the patient should be corrected.

[0015] Furthermore, the optical device can comprise an interface configured to provide the feedback signal to the user, wherein the interface is configured to communicate with the user and / or with the patient.

[0016] According to an exemplary embodiment of the present application, a respective and corresponding method for determining a patient position and / or a patient rotation of a patient to be X-ray irradiated by an X-ray system is proposed. The method can comprise the steps of emitting a horizontal laser line onto the patient by a laser source, detecting the course of the laser line emitted onto the patient by a detector. The method can further comprise the steps of determining the patient position and / or the patient rotation of the patient based on an analysis of the detected course of the laser line using an analysis unit, verifying whether the determined patient position and / or the patient rotation of the patient corresponds to a predetermined reference parameter using the analysis unit, and generating a feedback signal based on a result of the verification by the analysis unit.

[0017] The predetermined reference parameter can be a parameter used for a reference position and / or rotation which enables an improved or optimal X-ray image quality. For example, in order to generate a high quality chest X-ray image for displaying a lung, a reference parameter can be a symmetrical position of the patient in front of an X-ray sensor. In particular, a center line of the patient can be aligned symmetrically with a center line of the X-ray sensor, wherein the center line of the patient extends from a top (head) of the patient to a bottom (feet) of the patient.

[0018] According to an exemplary embodiment of the present application, the laser source is arranged to emit the laser line along an emission direction, the emission direction extending along an imaginary line from the laser source to the patient. The detector is arranged to detect the course of the laser line along a detection direction, the detection direction extending along an imaginary line from the detector to the patient, wherein the emission direction of the laser source and the detection direction of the detector form an angle in a range between 40 and 45 degrees.

[0019] For example, the emission direction extends horizontally with respect to an extension direction of the X-ray sensor, in other words, the imaginary line from the laser source to the patient is perpendicular to a center line of the X-ray sensor. Accordingly, the detection direction does not extend horizontally with respect to the extension direction of the X-ray sensor (not perpendicular to the center line of the X-ray sensor). The respective arrangement of the emission direction and the detection direction can be as described above, or can be arranged inversely. The use of an angle between 40 and 45 degrees allows to reduce the risk of the laser line being emitted onto the eyes of the patient. Furthermore, the angle can be suitable for accurately detecting a change of the course of the laser line by the detector.

[0020] According to an exemplary embodiment of the present application, the method for determining a patient position and / or a patient rotation of a patient to be X-ray irradiated by an X-ray system can further comprise emitting the laser line by the laser source along an emission direction, the emission direction extending along an imaginary line from the laser source to the patient. Detecting the course of the laser line by the detector along a detection direction, the detection direction extending along an imaginary line from the detector to the patient, and wherein the emission direction of the laser source and the detection direction of the detector form an angle in a range between 40 to 45 degrees.

[0021] According to an exemplary embodiment of the present application, the generated feedback signal is implemented as a control signal configured to control the patient position and / or the patient rotation when received by an X-ray system or a patient positioning system.

[0022] In particular, the control signal is received by a patient positioning system for changing the patient position and / or the patient rotation upon reception of the control signal. The feedback signal can be provided as an optical, acoustic and / or haptic feedback signal for indicating the verification result, wherein the respective optical, acoustic, haptic signal indicates a correct or incorrect patient position and / or patient rotation. The patient positioning system can be part of the optical device or the patient positioning system can be part of the X-ray system or the patient positioning system can be an additional part, single system provided additionally for the optical device and / or the X-ray system. Whether the patient positioning system is part of the optical device can depend on the respective embodiment of the present application. However, the optical device comprises the feedback signal which can be received by the additional (or single part) patient positioning system. The control signal can be configured to control the patient position and / or the patient rotation in such a way that the control signal can comprise the determined patient position / patient rotation (or both) and the control signal can comprise a value of the difference of the determined position / patient rotation to a reference parameter. Thus, the control signal can be used to correct the position / patient rotation with respect to the difference value. In particular, the patient positioning system can use the control signal in order to adjust the patient position / patient rotation based on the difference value.

[0023] According to an exemplary embodiment of the present application, the method for determining a patient position and / or a patient rotation of a patient to be X-ray irradiated by an X-ray system can further comprise using the generated feedback signal for controlling the patient position and / or the patient rotation when received by an X-ray system or a patient positioning system, the generated feedback signal being implemented as a control signal.

[0024] According to a first aspect of the present application, a spatial coordinate of a vertical center line of an X-ray sensor of the X-ray system is stored in the optical device, and wherein the analysis unit is configured to compare the determined patient position and / or patient rotation with the stored spatial coordinate. The vertical center line of the X-ray sensor is embodied as the reference parameter.

[0025] For example, the spatial coordinate can be stored in the analysis unit. Alternatively, the spatial coordinate can be received by the optical device from an external data storage, in which the spatial coordinate can be stored. In the context of the present application, the term "vertical center line" is to be understood as describing a center line of the X-ray sensor, which extends vertically in the center of the X-ray sensor. In particular, the X-ray sensor can comprise a left end and a right end, wherein the center line is equally spaced apart from both the left end and the right end.

[0026] According to an exemplary embodiment of the present application, the method for determining a patient position and / or patient rotation of a patient to be X-ray irradiated by an X-ray system can further comprise storing a spatial coordinate of a vertical center line of an X-ray sensor of the X-ray system in the optical device. The determined patient position and / or patient rotation is compared with the stored spatial coordinate using the analysis unit, wherein the vertical center line of the X-ray sensor is the reference parameter.

[0027] According to an exemplary embodiment of the present application, spatial coordinates of a left upper end point (LU) of the X-ray sensor, a left lower end point (LL) of the X-ray sensor, a right upper end point (RU) of the X-ray sensor, and a right lower end point (RL) of the X-ray sensor, and a vertical center line of the X-ray sensor are stored in the optical device. The analysis unit is configured to calculate a vertical left line between the left upper end point (LU) and the left lower end point (LL), wherein the vertical left line is curved due to the presence of the patient. The analysis unit is further configured to calculate a vertical right line between the right upper end point (RU) and the right lower end point (RL), wherein the vertical right line is curved due to the presence of the patient. Furthermore, the analysis unit is configured to calculate a first intersection point (PI) between a detected course of the line and the calculated vertical left line, and wherein the analysis unit is configured to calculate a second intersection point (P2) between the detected course of the line and the calculated vertical right line. Furthermore, the analysis unit is configured to calculate a left angle between a line segment from the left upper end point (LU) to the calculated first intersection point (PI) and a line segment from the calculated first intersection point (PI) to the left lower end point (LL). The analysis unit is configured to calculate a right angle between a line segment from the right upper end point (RU) to the calculated second intersection point (P2) and a line segment from the calculated second intersection point (P2) to the right lower end point (RL), wherein the analysis unit is configured to determine whether the left angle and the right angle are equal.

[0028] If the left angle and the right angle are equal, the patient position and / or the patient rotation of the patient corresponds to the predetermined reference parameter. If the left angle and the right angle are not equal, the patient position and / or the patient rotation of the patient needs to be corrected. The left angle can be a left side angle at the left side of the patient and the right angle can be a right side angle at the right side of the patient. The optical device can be configured to create a feedback signal which is implemented as a control signal for the X-ray system and / or for the patient positioning system, when the optical device has determined (calculated) that the left angle and the right angle are not equal. The angles are equal, for example, when the patient is aligned symmetrically to the center line of the X-ray sensor. The calculation of the vertical left line can be done without a patient in front of the X-ray sensor, in which case the vertical line (left and right) travels in a straight line from the right upper end point (RL) to the right lower end point (RU). When a patient is present in front of the X-ray sensor, a bending of the vertical line (left vertical line and / or right vertical line) can occur and the intersection points PI and P2 are calculated, wherein these intersection points PI and P2 can be used as new trajectory points for the vertical left line and / or the vertical right line. In particular, the bending of the vertical line is caused by the calculation of the intersection points PI and P2. The intersection points can be detected by a detector of the optical device. The intersection points PI and P2 and thus the curved course of the vertical line can be different for different patients. In particular, the optical device can be configured to calculate the intersection points PI and P2 when (by the optical device, preferably by the analysis unit) detecting and analyzing the horizontal laser line. The horizontal laser line and the part of the horizontal laser line which is bent due to the presence of the patient can be analyzed from one side to the other side, the two ends of the curved line can be considered as PI and P2. This calculation and / or analysis of PI and / or P2 can be performed by the analysis unit, preferably by a calculation performed by a processor, for example. In particular, the bent laser line can be determined and thereafter the analysis unit calculates the intersection points PI and P2.

[0029] According to an exemplary embodiment of the present application, the method for determining a patient position and / or a patient rotation of a patient to be X-ray irradiated by an X-ray system can further comprise storing spatial coordinates of a left upper end point (LU) of the X-ray sensor, a left lower end point (LL) of the X-ray sensor, a right upper end point (RU) of the X-ray sensor and a right lower end point (RL) of the X-ray sensor and a vertical center line of the X-ray sensor in the optical device. Further, the method comprises calculating a vertical left line between the left upper end point (LU) and the left lower end point (LL) using the analysis unit, wherein the vertical left line is curved due to the presence of the patient. A vertical right line between the right upper end point (RU) and the right lower end point (RL) is calculated using the analysis unit, wherein the vertical right line is curved due to the presence of the patient. Further method steps can comprise calculating a first intersection point (P1) between a detected course of the line and the calculated vertical left line by the analysis unit and calculating a second intersection point (P2) between a detected course of the line and the calculated vertical right line. The method can further comprise calculating a left angle between a line segment from the left upper end point (LU) to the calculated first intersection point (P1) and a line segment from the calculated first intersection point (P1) to the left lower end point (LL) using the analysis unit and calculating a right angle between a line segment from the right upper end point (RU) to the calculated second intersection point (P2) and a line segment from the calculated second intersection point (P2) to the right lower end point (RL). Further, the method comprises determining whether the left angle and the right angle are equal using the analysis unit. Depending on the determination of the angle equality or inequality, the method can further comprise the step of determining whether the patient position and / or the patient rotation is correct. In particular, the patient position can be determined by the shift of P1 and P2 and the patient rotation by the angle formed at P1 and P2. For example, if the angles are not equal, the patient is rotated. If the intersection points P1 and P2 are asymmetrically spaced from the center line of the X-ray sensor, the patient position is not correct. In Figure 3 and 4 In, a detailed determination of the patient position and / or the patient rotation is illustrated.

[0030] According to an exemplary embodiment of the present application, the feedback signal is embodied as a control signal configured to control the patient position and / or the patient rotation of the patient based on a difference between the left angle and the right angle determined by the analysis unit.

[0031] When the X-ray system and / or the patient positioning system receives the control signal, a control of the patient position and / or the patient rotation can be initiated. The control signal can be used to indicate whether the patient position and / or the patient rotation is correct with respect to a reference parameter, wherein the reference parameter can be the center line of the X-ray sensor. For example, if the difference between the angles is zero, the control signal can indicate that no change of the patient position and / or the patient rotation is required. Thus, the patient positioning system can not change the position and / or the rotation of the patient. In contrast, if the difference between the angles is determined, the patient position and / or the patient rotation has to be changed and the control signal controls the patient positioning system such that the change of the patient position and / or the patient rotation can be initiated, performed.

[0032] According to exemplary embodiments of the present application, the method for determining a patient position and / or a patient rotation of a patient to be X-ray irradiated by an X-ray system can further comprise the step of controlling the patient position and / or the patient rotation of the patient using the analysis unit based on a difference between the left angle and the right angle, wherein the step can further comprise generating a feedback signal, which is implemented as a control signal for performing the above-mentioned control.

[0033] According to exemplary embodiments of the present application, the analysis unit is configured to detect a gap in the course of the laser line, which is caused by the presence of the patient. The analysis unit is further configured to detect a left end point (L) of the patient using a line detection algorithm, wherein the left end point (L) corresponds to a left point on the course of the laser line, at which the horizontal portion of the laser line ends. Furthermore, the analysis unit is configured to detect a right end point (R) of the patient using the line detection algorithm, wherein the right end point (R) corresponds to a right point on the course of the laser line, at which the horizontal portion of the laser line ends. In the optical device, spatial coordinates of a vertical center line of the X-ray sensor are stored. Furthermore, the analysis unit is configured to calculate a midpoint between the left end point (L) and the right end point (R), wherein the analysis unit is configured to calculate whether the midpoint is positioned on the vertical center line of the X-ray sensor.

[0034] If the midpoint is located on the vertical center line of the X-ray sensor, the patient position is correct. If the midpoint is not located on the vertical center line of the X-ray sensor, the patient position needs to be corrected and the feedback signal is configured to indicate that the patient position needs to be corrected. In other words, the analysis unit can be configured to detect a left end point, which corresponds to the left end of a straight horizontal laser line adjacent to the (changed) course of the detected laser line. The analysis unit can be configured to detect a right end point, which corresponds to the right end of a straight horizontal laser line adjacent to the right side of the beginning / end of the (changed) course of the detected laser line. The left end point (L) of the patient can correspond to a left point on the course of the laser line at which the horizontal portion of the course of the laser line ends and a gap begins. Conversely, the right end point (R) of the patient corresponds to a right point on the course of the laser line at which the horizontal portion of the course of the laser line begins and a gap ends (viewed from left to right). The spatial coordinates of the vertical center line of the X-ray sensor can be stored in the analysis unit. Alternatively, the spatial coordinates can be received by the optical device from an external data storage. In Figure 6 and 7 a detailed correction of the patient position can be described.

[0035] According to exemplary embodiments of the present application, the method for determining a patient position and / or a patient rotation of a patient to be X-ray irradiated by an X-ray system can further comprise the steps of detecting, by the analysis unit, a gap in the course of the laser line, which is due to the presence of the patient. The method can further comprise detecting a left end point (L) of the patient using a line detection algorithm, wherein the left end point (L) corresponds to a left point on the course of the laser line at which the horizontal portion of the laser line ends, and detecting a right end point (R) of the patient using the line detection algorithm, wherein the right end point (R) corresponds to a right point on the course of the laser line at which the horizontal portion of the laser line ends. Furthermore, the method can comprise storing, in the optical device, spatial coordinates of a vertical center line of the X-ray sensor, and calculating a midpoint between the left end point (L) and the right end point (R), and calculating whether the midpoint is located on the vertical center line of the X-ray sensor. The above-mentioned detection and calculation steps can be performed by the analysis unit.

[0036] According to exemplary embodiments of the present application, the generated feedback signal is implemented as a control signal configured to control the determined patient position based on the difference between the midpoint of the X-ray sensor and the vertical center line calculated by the analysis unit.

[0037] When the X-ray system and / or the patient positioning system receives the control signal, a control of the patient position and / or rotation can be initiated. For example, if there is a difference between the midpoint of the X-ray sensor and the centerline, a correction of the patient position can be required. For example, the sign of the difference can indicate whether the patient has to be moved to the left or to the right, wherein a positive sign means that the patient can have to be moved to the left and a negative sign means that the patient can have to be moved to the right. The magnitude of the difference can indicate how far the patient has to be moved or is moved. Thus, the generated feedback signal can be configured to control based on the sign of the difference and the magnitude of the difference and / or the generated feedback signal can at least be configured to indicate the sign of the difference and / or the magnitude of the difference. In contrast, if there is no difference, no correction of the patient position is required. Thus, the feedback signal (implemented as control signal) can first indicate whether a correction is necessary, wherein this can be indicated to the patient and / or staff by optical, haptic, acoustic feedback signals. Second, the feedback signal can be used to control the patient position (if detected to be incorrect), wherein the position is controlled by the X-ray system itself and / or by the patient positioning system or wherein the patient is asked by an automated voice command to move to the left or to the right until the position is correct.

[0038] According to exemplary embodiments of the present application, the method for determining a patient position and / or a patient rotation of a patient to be X-rayed by an X-ray system can further comprise generating a feedback signal implemented as a control signal and controlling the determined patient position based on a difference between the midpoint of the X-ray sensor and the vertical centerline calculated by the analysis unit. In particular, the method comprises controlling the determined patient position based on a sign of the difference and / or a magnitude of the difference.

[0039] According to exemplary embodiments of the present application, the analysis unit can be configured to detect a gap in the course of the laser line using a line detection algorithm, the gap being formed due to the shape of the patient. Further, the analysis unit can be configured to determine a length of the gap of the course of the laser line at a left end position of the patient and at a right end position of the patient using a line detection algorithm. Further, the analysis unit can be configured to calculate the patient rotation from the determined length of the left end position of the patient and from the determined length of the right end position of the patient.

[0040] If the length of the gap at the left end position is not equal to the length of the gap at the right end position, a correction of the patient rotation can be required. Thus, if the length of the two gaps is equal, the patient rotation is correct, wherein a correct patient rotation can be defined as such that the left-right axis of the patient is parallel to the plane of the X-ray sensor. The left-right axis of the patient is to be understood as describing an axis extending from the left side of the patient through the right side of the patient, wherein said axis extends horizontally, which means perpendicular to the centerline of the patient. Figure 7 A detailed description of determining the patient rotation is described.

[0041] According to exemplary embodiments of the present application, the method for determining a patient position and / or a patient rotation of a patient to be X-ray irradiated by an X-ray system can further comprise the steps of detecting a gap in the course of the laser line using a line detection algorithm, said gap being formed due to the shape of the patient. Determining the length of the gap of the course of the laser line at a left end position of the patient and at a right end position of the patient using a line detection algorithm and calculating the patient rotation depending on the determined length of the left end position of the patient and depending on the determined length of the right end position of the patient. These steps can be performed by an analysis unit.

[0042] According to exemplary embodiments of the present application, the feedback signal is implemented as a control signal configured to control the determined patient rotation based on a gap difference between the length of the left end position of the patient and the length of the right end position of the patient.

[0043] For example, if there is a gap difference value, the feedback signal (control signal) can control the X-ray system and / or the patient positioning system to correct the patient rotation. In the figures, a detailed correction of the patient rotation is described.

[0044] According to exemplary embodiments of the present application, the method for determining a patient position and / or a patient rotation of a patient to be X-ray irradiated by an X-ray system can further comprise the steps of generating a feedback signal implemented as a control signal and controlling the determined patient rotation based on a gap difference between the length of the left end position of the patient and the length of the right end position of the patient using the generated feedback signal.

[0045] According to exemplary embodiments of the present application, the analysis unit is configured to detect an inhalation state of the patient. The analysis unit is configured to determine the inhalation state after determining the patient position and after determining that the patient position corresponds to the predetermined reference parameter.

[0046] The inspiration state can be determined before the analysis unit can determine the patient position and / or the patient rotation is correct. Depending on the inspiration state, the quality of the X-ray image can be affected. For example, full inspiration is preferred when the muscle structure of the chest and / or back of the patient should be clearly visible in the X-ray image, or for example, the fully expanded lungs. The inspiration state can be determined after it has been determined that the patient position and / or the patient rotation is correct, so that the determination of the inspiration state can not be affected by a failure due to the patient position and / or rotation. A pseudo-lung volume time profile analysis can be obtained for detecting an optimal inspiration point, wherein the decision point for the image acquisition can be based on the lung volume, and thus on the inspiration. For example, the optimal inspiration point can be the maximum inspiration. In the figures, a detailed correction of the inspiration state of the patient is described. For example, Figure 5 A determination of the inspiration state of a patient is illustrated.

[0047] According to exemplary embodiments of the present application, the method for determining a patient position and / or a patient rotation of a patient to be X-ray irradiated by an X-ray system can further comprise the step of detecting an inspiration state of the patient.

[0048] Determining the inspiration state can be performed after determining the patient position and after determining that the patient position corresponds to a predetermined reference parameter. The determining step can be performed by an analysis unit.

[0049] According to exemplary embodiments of the present application, the analysis unit can be configured to determine the inspiration state at consecutive time points based on a breathing cycle, which is derived from a change of the approximated result of the axial cross-sectional area under the course of the detected laser line. The analysis unit can be configured to determine the axial cross-sectional area of expiration and inspiration of the patient.

[0050] The breathing cycle can be determined over a period of time, so that a decision for an optimal X-ray imaging point can be derived from the inspiration state. The breathing cycle can comprise the inspiration process and the expiration process of the patient over a period of time. When determining the breathing cycle, a pseudo-volume time profile of the lungs of the patient can be derived based on the inspiration and expiration of the patient.

[0051] According to exemplary embodiments of the present application, the method for determining a patient position and / or a patient rotation of a patient to be X-ray irradiated by an X-ray system can further comprise the step of determining an inspiration state at consecutive time points based on a breathing cycle, which is derived from a change of the approximated result of the axial cross-sectional area under the course of the detected laser line. The method can further comprise the step of determining the axial cross-sectional area of expiration and inspiration of the patient. The method steps can be performed by an analysis unit.

[0052] According to a second aspect of the present application, a system for controlling a patient position and / or a patient rotation of a patient to be X-ray irradiated by an X-ray device is described. The system comprises an X-ray device for generating an X-ray image of the patient. The X-ray device comprises an X-ray source, an X-ray sensor. Further, the system comprises an optical arrangement according to any of the embodiments as described above, wherein the system is configured to control the patient position and / or the patient rotation of the patient based on the feedback signal generated by the optical arrangement.

[0053] The X-ray sensor can be arranged opposite to the X-ray source such that the patient can be arranged between the X-ray source and the X-ray sensor for being X-ray irradiated. The distance between the X-ray sensor and the X-ray source can depend on the respective embodiment of the available X-ray device. In particular, the X-ray source is arranged in such a way that the X-ray radiation emitted by the X-ray source is emitted on the patient and the X-ray sensor can detect the residual X-ray radiation altered due to the anatomy of the patient.

[0054] According to exemplary embodiments of the present application, a method for controlling a patient position and / or a patient rotation of a patient to be X-ray irradiated by an X-ray device can comprise the following steps: generating an X-ray image of the patient by the X-ray device, wherein the generation of the X-ray image can be performed by the X-ray device using an X-ray source and an X-ray sensor. The method can further comprise the step of controlling the patient position and / or the patient rotation of the patient based on a feedback signal generated by the optical arrangement, which has been described with respect to the embodiments above.

[0055] According to exemplary embodiments of the present application, the optical arrangement is arranged at one side of the X-ray source. In this arrangement, the patient to be X-ray irradiated by the X device is placed together with the optical arrangement between the X-ray sensor on one side and the X-ray source on the other side.

[0056] According to exemplary embodiments of the present application, the patient position and / or the patient rotation is determined before triggering the X-ray image. In order to avoid malfunctions in the X-ray image, thus in order to provide an X-ray image with high quality, the patient position and / or the patient rotation and / or the patient inspiration can be determined before the X-ray image can be triggered. The method for controlling a patient position and / or a patient rotation of a patient to be X-ray irradiated by an X-ray device can further comprise determining the patient position and / or the patient rotation before triggering the X-ray image.

[0057] According to exemplary embodiments of the present application, the optical device is configured for determining an inhalation state of the patient, and wherein the system is configured to trigger a start of an X-ray imaging procedure based on a result of the inhalation state detection performed by the optical device. In particular, the X-ray device can be configured to trigger the start of the X-ray imaging procedure based on the result of the inhalation state detection. As described with respect to the embodiments above, the inhalation state is determined at consecutive points in time based on a breathing cycle, which is derived from a change of an approximation of the axial cross-sectional area under the course of the detected laser line. This breathing cycle can be used to trigger the start of the X-ray imaging procedure.

[0058] The method for controlling a patient position and / or a patient rotation of a patient to be X-ray irradiated by an X-ray device can further comprise triggering a start of an X-ray imaging procedure based on a result of the inhalation state detection performed by the optical device. In particular, triggering the start of the X-ray imaging procedure is based on the result of the inhalation state detection.

[0059] According to a third aspect of the present application, a method for determining a patient position and / or a patient rotation of a patient to be X-ray irradiated with an X-ray device comprises the steps of emitting a horizontal laser line onto the patient by a laser source, detecting a course of the laser line on the patient by a detector, wherein the detector and the laser source are vertically spaced apart from each other. The method further comprises the steps of determining a patient position and / or a patient rotation based on an analysis of the detected course of the laser line by an analysis unit, verifying whether the determined patient position and / or patient rotation corresponds to a predetermined reference parameter of the analysis unit, and providing a feedback signal based on a result of the verification of the analysis unit. Spatial coordinates of a vertical centerline of an X-ray sensor of the X-ray system are stored. The determined patient position and / or patient rotation is compared to the stored spatial coordinates by the analysis unit. The vertical centerline of the X-ray sensor is the reference parameter.

[0060] The horizontal laser line can be emitted onto a body surface of the patient, in particular onto a chest or a back, and the detector detects the course of the laser line on the body surface of the patient.

[0061] According to exemplary embodiments of the present application, the method further comprises the step of controlling the patient position and / or patient rotation using the feedback signal configured as a control signal, wherein the control signal is received by a patient positioning system for changing the patient position and / or patient rotation upon reception of the control signal.

[0062] The controlling can comprise generating a control signal (feedback signal) and can comprise controlling a change of the patient position by controlling a patient positioning system. In contrast, the controlling can comprise only generating a control signal, and the patient positioning system can use the control signal.

[0063] According to another aspect of the present application, a program element for determining a patient position and / or a patient rotation of a patient to be subjected to X-ray irradiation with an X-ray device is presented. When executed by a processor of an optical device as presented herein, the program element is adapted to cause the optical device to emit a horizontal laser line onto the patient by means of the laser source, to detect a course of the laser line on the patient by means of the detector, to determine the patient position and / or the patient rotation based on an analysis of the detected course of the laser line by means of the analysis element, to verify whether the determined patient position and / or the patient rotation corresponds to a predetermined reference parameter by means of the analysis element, to provide a feedback signal based on a result of the verification by means of the analysis element.

[0064] The program element can be part of a computer program, but it can also be the whole computer program. For example, the program element can be used to update an already existing computer program to implement the present application.

[0065] The program element can be stored on a computer readable medium. The computer readable medium can be regarded as a storage medium, e.g. a USB stick, a CD, a DVD, a data store, a hard disc, or any other medium as mentioned above on which the program element can be stored. BRIEF DESCRIPTION OF DRAWINGS

[0066] The above mentioned aspects and other aspects of the present application are apparent from the examples of the embodiments described hereinafter and are explained with reference to examples of embodiments. The application will be described more fully hereinafter with reference to examples of embodiments. The application may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. In the context of the present application, the singular form "a", "an" and "the" include plural references unless the context clearly dictates otherwise.

[0067] Figure 1 An optical device and an X-ray system according to exemplary embodiments of the present application are illustrated.

[0068] Figure 2 A horizontal laser line used in exemplary embodiments of the present application is illustrated.

[0069] Figure 3 A determination of a patient position and / or a patient rotation according to exemplary embodiments of the present application is illustrated.

[0070] Figure 4 A determination of a patient position and / or a patient rotation according to exemplary embodiments of the present application is illustrated.

[0071] Figure 5 A determination of an inhalation state according to exemplary embodiments of the present application is illustrated.

[0072] Figure 6 A determination of a patient position and / or a patient rotation according to exemplary embodiments of the present application is illustrated.

[0073] Figure 7 Fig. illustrates the determination of a patient position and / or a patient rotation according to exemplary embodiments of the present application.

[0074] Figure 8 Fig. illustrates a flow chart of a method for determining a patient position and / or a patient rotation according to exemplary embodiments of the present application.

[0075] Figure 9 Fig. illustrates a flow chart of a method for determining a patient position and / or a patient rotation according to exemplary embodiments of the present application.

[0076] List of reference signs:

[0077] 100 optical device

[0078] 101 laser source

[0079] 102 detector

[0080] 103 X-ray sensor

[0081] 104 X-ray source

[0082] 105, 605 patient

[0083] 106 X-ray system

[0084] 107 laser line

[0085] 108 detection direction

[0086] 109 evaluation unit

[0087] a angle

[0088] 207-1 laser line

[0089] 207-2 laser line

[0090] 310 center line of the X-ray sensor

[0091] 307-1 horizontal laser line

[0092] 307-2 laser line

[0093] 607-1 horizontal laser line

[0094] 607-2 laser line

[0095] 611 patient left point

[0096] 612 patient right point

[0097] 613, 614 gap

[0098] Intersection of P1 and P2

[0099] RU top right endpoint

[0100] RL bottom right endpoint

[0101] LU top left endpoint

[0102] LL lower left endpoint

[0103] L left endpoint

[0104] R right endpoint

[0105] Angles Θ1 and Θ2

[0106] x0 Centerline of X-ray sensor

[0107] M midpoint

[0108] Δs offset Detailed Implementation

[0109] Figure 1 The illustration shows an optical device (100) for an X-ray system (106) used to determine the patient position and / or rotation of a patient (105) to be irradiated by the X-ray system (106). (See diagram from...) Figure 1 As can be seen, the optical device (100) includes a laser source (101) and a detector (102) vertically spaced from the laser source (101). In other words, the detector is positioned vertically below the laser source. Therefore, the detector is positioned at a lower vertical height than the laser source. The positions of the laser source and the detector can be interchanged, allowing the detector to be positioned vertically above the laser source. (See also...) Figure 1 As can be seen, the vertical arrangement of the laser source (101) and detector (102) is relative to a horizontal line and / or perpendicular to the ground plane, where the optical device (100) preferably has an X-ray system is used and applied at the ground plane. In particular, the vertical arrangement is parallel to the center line of the patient (105), which extends from the head to the feet of the patient (105).

[0110] The detector (102) can be a camera, a CCD sensor or any other suitable optical system capable of detecting the laser line and / or the radiation emitted from the laser line on the patient. The laser source (101) is configured to emit a horizontal laser line (107) onto the patient (105), wherein the detector (102) is configured to detect the course of the laser line (107) emitted onto the patient (105). As understood by the person skilled in the art, the horizontal laser line (107) extends in a 3D space parallel to the horizontal line and / or parallel to the plane at which the optical arrangement (100) of the preferably having an X-ray system is used and applied when being emitted. The analysis unit (109) is configured to determine a patient position and / or a patient rotation of the patient (105) based on an analysis of the course of the detected laser line (107). Further, the analysis unit (109) is configured to verify whether the determined patient position and / or patient rotation of the patient (105) corresponds to a predetermined reference parameter, and wherein the analysis unit (109) is configured to generate a feedback signal based on a result of the verification. The laser source (101) is arranged to emit the laser line (107) along an emission direction, which extends along an imaginary line from the laser source (101) to the patient (105). As can be seen in Figure 1 , the emission direction of the laser line (107) is illustrated as a visible laser beam (107). The detector (102) is arranged to detect the course of the laser line (107) along a detection direction (108), which extends along an imaginary line from the detector (102) to the patient (105). In Figure 1 , the detection direction (108) is illustrated as two lines (108), which illustrate the visual area of the detector for detecting the laser line (107) on the patient (105). The emission direction of the laser source (102) and the detection direction (108) of the detector (102) form an angle (a) in the range between 40 to 45 degrees. The analysis unit (109) can generate a feedback signal, which is implemented as a control signal configured to control the patient position and / or the patient rotation when being received by the X-ray system or the patient positioning system. As can be seen in Figure 1As can be seen in, the detector (102) is arranged below the laser source (101), but it is also possible to arrange it in the opposite way. Furthermore, a system (106) for controlling a patient position and / or a patient rotation of a patient (105) to be X-ray irradiated by an X-ray device is illustrated. The system comprises an X-ray device for generating an X-ray image of a patient, the X-ray device comprising an X-ray source (104) and an X-ray sensor (103). The system (106) further comprises the optical arrangement (100) described above, and wherein the system (106) is configured to control the patient position and / or the patient rotation of the patient (105) based on the feedback signal generated by the optical arrangement (100). The detector (102) of the optical arrangement (100) can be arranged below the X-ray source (104) and the laser source (101) of the optical arrangement (100) can be arranged above the X-ray source (104), or vice versa. The analysis unit (109) can also be part of the X-ray system. As in Figure 1 As can be seen in, the patient (105) is positioned in front of the X-ray sensor (103) of the X-ray system and depending on the position and / or rotation of the patient (105) in front of the X-ray sensor (103), the generated X-ray image can be affected. Therefore, the patient (105) should preferably not be rotated and aligned symmetrically in front of the X-ray sensor (105). In Figure 1 In, the patient (105) is arranged in the middle of the X-ray sensor (103), wherein a center line of the patient (105) is parallel to a center line of the X-ray sensor (103), wherein the center line of the X-ray sensor (103) extends from a top to a bottom of the X-ray sensor.

[0111] Figure 2 A laser line (207) is illustrated which is emitted horizontally onto the patient (105). The patient (105) is positioned in front of the X-ray sensor (103) and the optical arrangement (100) emits the laser line (207) onto the patient (105). The course of the laser line (207) is changed due to the shape of the patient (105). As can be seen in Figure 2 As can be seen in, the course of the continuous laser line (207-1) is different from the course of the dashed line (207-2), wherein the difference in the course between these two laser lines (207-1, 207-2) can be based on a patient position and / or a patient rotation and / or a patient inhalation state. In particular, the difference between the continuous laser line (207-1) and the changed laser line (207-2) is caused by the presence of the patient. Both laser lines (207-1, 207-2) can be emitted laser lines of a horizontally extending laser source, wherein, as in Figure 2As can be seen in Fig. 7, the laser lines (207-1, 207-2) are straight laser lines (207-1, 207-2) at the right and left side of the patient. When no patient is present, the course of the laser lines (207-1, 207-2) is not curved, so the course laser lines (207-1, 207-2) can be partially emitted on the X-ray sensor (103) (at the back of the patient). In contrast, if a patient is present, the laser lines (207-1, 207-2) are curved, which can be seen in Fig. 7. Figure 2 As can be seen in Fig. 7, the laser lines (207-1, 207-2) are straight laser lines (207-1, 207-2) at the right and left side of the patient. When no patient is present, the course of the laser lines (207-1, 207-2) is not curved, so the course laser lines (207-1, 207-2) can be partially emitted on the X-ray sensor (103) (at the back of the patient). In contrast, if a patient is present, the laser lines (207-1, 207-2) are curved, which can be seen in Fig. 7.

[0112] Figure 3 Fig. 7 illustrates the determination of a patient position and / or a patient rotation according to an exemplary embodiment of the present application. In particular, Figure 3 Fig. 7 illustrates the stored spatial coordinates of the vertical center line (310) of the X-ray sensor of the X-ray system in the optical device, wherein the analysis unit is configured to compare the determined patient position and / or patient rotation with the stored spatial coordinates, wherein the vertical center line (310) of the X-ray sensor is the reference parameter.

[0113] Furthermore, the spatial coordinates of the upper left end point (LU) of the X-ray sensor, the lower left end point (LL) of the X-ray sensor, the upper right end point (RU) of the X-ray sensor and the lower right end point (RL) of the X-ray sensor are stored in the optical device. The analysis unit is configured to calculate a vertical left line between the upper left end point (LU) and the lower left end point (LL), wherein the vertical left line is curved due to the presence of the patient. The analysis unit is configured to calculate a vertical right line between the upper right end point (RU) and the lower right end point (RL), wherein the vertical right line is curved due to the presence of the patient. Furthermore, the analysis unit is configured to calculate a first intersection point (PI) between the course of the detected laser line (307-2) and the calculated vertical left line and to calculate a second intersection point (P2) between the course of the detected laser line (307-2) and the calculated vertical right line. If a patient (105) stands in front of the X-ray sensor (103), the laser line (307) will be placed on the patient's chest and / or back. The optical device can analyze the course of the laser line (307) on the patient and can determine the patient position and / or patient rotation and determine whether this complies with the reference parameter, which can be the center line (310) of the X-ray sensor (103). The laser line (307-2) represents the laser line when placed on the patient's chest. Initially, the two vertical left and right lines are anchored at the top and bottom. In Figure 3In this context, the vertical left line and the vertical right line are curved due to the presence of the patient. In this way, the vertical left line and the vertical right line adapt to the contour of the patient. The intersection points (PI, P2) can be the end points of the contour of the patient and are considered as new trajectories of the vertical left line and the vertical right line, respectively. In particular, the optical device (100) can be configured to calculate the intersection points (PI and P2) when detecting and analyzing the course of the laser line (307-2) (by the optical device, preferably by the analysis unit). The course of the laser line (307-2) and the portion of the horizontal laser line (307) that is curved due to the presence of the patient can be analyzed from one side to the other side, the two ends of the curved laser line (307-2) can be considered as PI and P2. In particular, the patient position can be determined by the displacement of PI and P2 and the patient rotation by the angle formed at PI and P2. If the intersection points PI and P2 are not symmetrically spaced from the center line of the X-ray sensor, the patient position is incorrect. The laser line (307-1) illustrates the horizontal laser line (307-1) when no patient is present in front of the X-ray sensor (103).

[0114] Figure 4 The determination of the patient position and / or the patient rotation according to an exemplary embodiment of the present application is illustrated. In particular, Figure 4 The calculation of the left angle (Θ2) between the line segment from the upper left end point (LU) to the calculated first intersection point (PI) and the line segment from the calculated first intersection point (PI) to the lower left end point (LL) is illustrated. Furthermore, the calculation of the right angle (Θ1) between the line segment from the upper right end point (RU) to the calculated second intersection point (P2) and the line segment from the calculated second intersection point (P2) to the lower right end point (RL) is illustrated. The analysis unit (109) is configured to determine whether the left angle (Θ2) and the right angle (Θ1) are equal. Subsequently, the left angle (Θ2) and the right angle (Θ1) between the line segments are determined. If the patient position is aligned symmetrically to the center line (310) of the X-ray sensor (103), the angles formed by the curves should be equal. If this condition is not fulfilled, a feedback signal will be given to the patient (105), the patient positioning system and / or the user (medical staff) in order to correct the patient position. Geometrically, the determination and calculation of the line segments as well as the left angle (Θ2) and the right angle (Θ1) can be represented by the edges and the angles of a hexagon. In case of a patient (105) rotation, the left angle (Θ2) is greater than the right angle (Θ1), or the left angle (Θ2) is smaller than the right angle (Θ1), and the rotation error can be determined from this inequality of the angles. For example, if the angles (Θ1), (Θ2) are not equal, the patient is rotated.

[0115] Figure 5The detection of the inhalation state of the patient (105) is illustrated and wherein the analysis unit (109) is configured to determine the inhalation state after determining the patient position and after determining that the patient position corresponds to the predetermined reference parameter. The analysis unit (109) is configured to determine the inhalation state based on the breathing cycle, which is derived from the change in the approximated result of the axial cross-sectional area (Ati, At2) under the course of the detected laser line (307) at consecutive time points (ti, t2). Further, the analysis unit is configured to determine the axial cross-sectional area (Ati, At2) for the exhalation and inhalation of the patient. The axial cross-sectional area (Ati, At2) is determined between the unchanged course of the laser line (307-1) and the changed course of the changed laser line (307-2) due to the presence of the patient (105). The determined axial cross-sectional area (Ati) can correspond to the exhalation of the patient at time point ti and the determined axial cross-sectional area (At2) can correspond to the inhalation of the patient at time point t2. From the approximated result of the axial cross-sectional area (Ati, At2) at consecutive time sampling, the breathing cycle of the patient can be derived. Figure 5 As can be seen in the above, the approximated result of the axial cross-sectional area (At2) for inhalation can be greater than the approximated result of the axial cross-sectional area (Ati) for exhalation. The breathing cycle of the patient can be derived using the change in the approximated result of the axial cross-sectional area (Ati, At2) at consecutive time sampling and the displacement of the center of gravity of the respective axial cross-sectional area. The determination of the axial cross-sectional area can be calculated using the following formula:

[0116]

[0117] In this formula, the variables can be as follows, xo can be the first value, n can be the number of terms, j can be the increment variable, x can be the data point, and h can be the maximum value of x. The derived breathing cycle and the determined axial cross-sectional area can be displayed on a screen and / or a display, which can be part of the optical device. A digital twin of the patient's lung simulating the inhalation and exhalation can also be presented on the screen for a better visual experience.

[0118] Figure 6The detection of gaps (613, 614) in the course of the laser line (607) due to the presence of the patient is illustrated. The analysis unit (109) is configured to detect the left end point (L) of the patient using a line detection algorithm, wherein the left end point (L) corresponds to a left point on the course of the laser line (607) at which the horizontal portion of the laser line (607-1) ends. Further, the analysis unit (109) is configured to detect the right end point (R) of the patient using the line detection algorithm, wherein the right end point (R) corresponds to a right point on the course of the laser line (607) at which the horizontal portion of the laser line (607-1) ends. The spatial coordinates of the vertical center line (310) of the X-ray sensor (103) are stored in the optical device. In Figure 6 the center line (310) of the X-ray sensor is illustrated by the (x0) coordinate. The analysis unit (109) is configured to calculate a midpoint (M) between the left end point (L) and the right end point (R), wherein the analysis unit (109) is configured to calculate whether the midpoint (M) lies on the vertical center line (310) of the X-ray sensor. Gaps (613, 614) can be introduced by the patient in the laser line (607) at the left and right edges of the patient. In Figure 6 the patient is simplified to a rectangular frame. A line detection algorithm can be used to follow the laser line and detect the gaps (613, 614) in the laser line (607). This algorithm can be performed in real time. The algorithm is used to determine the left and right ends of the patient by finding the points (L) and (R) at which the horizontal laser line (607-1) ends. The points (L) and (R) are found as the ends of the horizontal laser line (607-1) just before the gaps (613, 614). A midpoint (M) can be calculated, and if the midpoint (M) does not lie at x=x0, the patient is off-center, e.g., to the left or right of the vertical center line (310) of the X-ray sensor (103), and a correction of the patient position can be necessary. The patient position can be corrected by an x-shift (As) of the midpoint (M) in order to center. Between the gaps (613, 614), a changed course of the laser line (607-2) can be formed which is changed due to the presence of the patient.

[0119] Figure 7Fig. 6 illustrates the detection of gaps (613, 614) in the course of the laser line (607) using a line detection algorithm, which gaps (613, 614) are formed due to the shape of the patient. The analysis unit (109) is configured to determine the length of the gaps (614) of the course of the laser line (607) at the left end position of the patient and at the right end position of the patient using the line detection algorithm, and wherein the analysis unit (109) is configured to calculate the rotation of the patient from the determined length of the left end position of the patient and from the determined length of the right end position of the patient. For example, if the patient position can be correct, a correction of the patient rotation can still be required. A still rotating patient can introduce different lengths of gaps at the left and right end of the patient. The left and right end of the patient can be determined using the features as described with respect to Fig. 5, and then the length of the gaps (613, 614) is determined using the line detection algorithm. The length of the gaps (613, 614) can be detected in real-time image processing, and a feedback signal can be provided to the patient and / or the patient positioning system and / or the user for performing a correction of the patient rotation. For example, it is determined whether the gap (614) is larger than the gap (613), which can be expressed by the following equation: Figure 6

[0120] gap(614) - gap(613) > m,

[0121] Furthermore, it can be determined whether the gap (614) is smaller than the gap (613), which can be expressed by the following equation

[0122] gap(614) - gap(613) < -m,

[0123] wherein m can be a predetermined fixed error margin m, for example m = 1 cm. If the gap (614) is larger than the gap (613), a feedback signal can indicate a right turn of the patient (and / or the user) (for narrowing the left gap) as long as the gap (614) is larger than the gap (613), wherein in this configuration the patient stands behind the X-ray sensor and the right side of the patient can be arranged next to the determined left end point (L). If the gap 614 is smaller than the gap 613, a feedback signal can indicate a left turn of the patient (to make the right gap narrower) as long as the gap 614 is smaller than the gap 613. Otherwise, the patient should be stationary, wherein the feedback signal can not provide a correction signal to the patient, the patient positioning system and / or the user.

[0124] Figure 8 ​Fig. illustrates a schematic diagram for determining patient position and / or patient rotation according to exemplary embodiments of the present application, wherein the determination can be integrated into an autonomous workflow integration. In an autonomous imaging scenario, the patient can need to be trained with respect to the autonomous procedure, which involves the initial positioning of the patient, error detection (patient position, patient rotation and patient inspiration state) and correction by feedback signals of the analysis unit (109). Figure 8It is illustrated how the training of the patient, the automatic error detection (patient position, patient rotation and patient inspiration state) and the triggering of the X-ray image are combined into the X-ray acquisition workflow. In step (S100) the patient enters the X-ray imaging lab. In step (S200) the patient is assessed for autonomous imaging based on the body condition. For example, to assess whether the patient is suitable enough for autonomous imaging, a set of patient assessment criteria can be followed. A first patient assessment criterion can be the response time, wherein it is checked whether the patient can successfully respond to an instruction within a prescribed and reasonable time (e.g. 5 seconds). A second patient assessment criterion can be the retry attempts, which means that the patient is instructed to try in case of a failure result during the training, for example, up to 3 or 5 attempts. A third patient assessment criterion can be the patient disability, wherein these disabilities can be categorized as cognitive disabilities, physical disabilities due to health conditions or age or other disabilities. In step (S200) the third patient assessment criterion can be assessed. If the patient assessment criteria are met, the method can proceed to step (S201), if not met, the method proceeds to step (S800). If the patient meets the third assessment criteria in step (S201), the patient can be trained for autonomous imaging. In step (S202) the patient can be informed about the initial positioning with respect to the laser lines emitted to the patient, wherein the information can be provided by an interactive video and / or by a medical staff. In step (S203) the patient can be trained about the provided feedback signals, which can be haptic feedback, optical feedback and / or audio feedback, wherein the patient can be trained about the patient position, the patient rotation and / or the patient inspiration state, about the feedback based error correction by means of a simulation drill and / or a video session. When the patient has successfully performed all steps (S201 to S203), then it proceeds to step (S300). In step (S300) the patient reaction is assessed and the suitability for autonomous imaging is determined using the first patient assessment criterion and the second patient assessment criterion. If these criteria are met, step (S400) is continued. In step (S400) the optical device determines the patient position and / or the patient rotation as described in the above mentioned embodiments. In particular, in step (S400) the method for determining the patient position and / or the patient rotation as in the various embodiments above is performed. After step (S400) it proceeds to step (S500), wherein in this step (S500) a correction of the determined patient position and / or patient rotation can be performed. In particular, in step (S500) the system for controlling the patient position and / or the patient rotation of the patient to be X-ray illuminated by the X-ray device can be used to control and / or correct the determined patient position and / or patient rotation, if a correction is needed. When this step has been successfully performed, step (S600) can be performed, wherein the triggering of the X-ray imaging can be started.In step (S700), the procedure of X-ray imaging can be completed and an X-ray image can be generated and in step (S900), the image acquisition is completed. If the patient does not meet the patient evaluation criteria in step (S200) and / or step (S300), a manual intervention can be required, wherein the method will proceed to step (S800) and the image acquisition can be completed without steps (S400 to S700). The steps described above can be performed using a patient training device, wherein the device can be an external part of the X-ray system and / or the X-ray apparatus and / or the optical device. On the other hand, the patient training device can be a training program, which can be included in the X-ray system and / or the X-ray apparatus and / or the optical device by means of a software or data processing unit.

[0125] Figure 9 Method steps for determining a patient position and / or a patient rotation of a patient to be irradiated with an X-ray apparatus are illustrated. The method comprises the following steps: (S0) arranging a patient in front of an X-ray sensor of an X-ray apparatus, (S1) emitting a horizontal laser line onto the patient by means of a laser source, (S2) detecting a course of the laser line on the patient by means of a detector. The detector and the laser source are vertically spaced apart from each other. Step (S3) comprises determining a patient position and / or a patient rotation based on an analysis of the detected course of the laser line by means of an analysis unit. Step (S4) comprises verifying by means of the analysis unit whether the determined patient position and / or patient rotation corresponds to a predetermined reference parameter. In step (S5), a feedback signal is provided based on the result of the verification by means of the analysis unit. If the feedback signal indicates that the determined patient position and / or patient rotation does not comply with the reference parameter, it can be returned to step (S0) and the patient can need to be arranged in front of the X-ray sensor again. In step (S4), it can be returned to step (S1) and / or step (S2) in order to emit the laser line onto the patient again and / or in order to detect the course of the laser line on the patient again. The method steps can be performed in the method steps (S400) of the method of Figure 8 The method can comprise a further step (S6) for controlling the patient position and / or the patient rotation using the feedback signal configured as a control signal, wherein the control signal is received by a patient positioning system for changing the patient position and / or the patient rotation upon reception of the control signal. While step (S6) can be used for controlling the patient position and / or the patient rotation, step (S0) can be restarted in order to arrange the patient again when the determination of the patient position and / or rotation is incorrect. As described with respect to Figure 8 and 9 The method described above can further comprise determining an inhalation state of the patient.

[0126] While the application has been illustrated and described in detail in the drawings and foregoing description, such illustration and description is to be considered illustrative or exemplary and not restrictive; the application is not limited to the disclosed embodiments.

[0127] Other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed application, from a study of the drawings, the disclosure, and the claims. In the claims, the word "comprising" does not exclude other elements or steps, and the word "a" or "an" does not exclude a plurality. A single processor or other unit can fulfill the functions of several items recited in the claims. The mere fact that measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage. Any reference signs in the claims should not be construed as limiting the scope.

Claims

1. An optical device for an X-ray system for determining a patient position and / or a patient rotation of a patient to be X-ray irradiated by the X-ray system, the optical device comprising: a laser source, and a detector vertically spaced apart from the laser source, wherein the laser source is configured to emit a horizontal laser line onto the patient, wherein the detector is configured to detect a course of the laser line emitted onto the patient, an analysis unit configured to determine the patient position and / or the patient rotation of the patient based on an analysis of the detected course of the laser line, wherein the analysis unit is configured to verify whether the determined patient position and / or patient rotation of the patient corresponds to a predetermined reference parameter, wherein the analysis unit is configured to generate a feedback signal based on a result of the verification, wherein spatial coordinates of a vertical center line of an X-ray sensor of the X-ray system are stored in the optical device, wherein the analysis unit is configured to compare the determined patient position and / or patient rotation with the stored spatial coordinates, and wherein the vertical center line of the X-ray sensor is the reference parameter.

2. The optical device of claim 1, wherein the laser source is arranged to emit the laser line along an emission direction, the emission direction extending along an imaginary line from the laser source to the patient, wherein the detector is arranged to detect the course of the laser line along a detection direction, the detection direction extending along an imaginary line from the detector to the patient, wherein the emission direction of the laser source and the detection direction of the detector form an angle in a range between 40 and 45 degrees.

3. The optical device of claim 1 or 2, wherein the generated feedback signal is implemented as a control signal, the control signal being configured to control the patient position and / or patient rotation when received by an X-ray system or a patient positioning system.

4. The optical device of claim 1 or 2, wherein spatial coordinates of a left upper end point (LU) of the X-ray sensor, a left lower end point (LL) of the X-ray sensor, a right upper end point (RU) of the X-ray sensor, and a right lower end point (RL) of the X-ray sensor, and a vertical center line of the X-ray sensor are stored in the optical device, wherein the analysis unit is configured to calculate a vertical left line between the left upper end point (LU) and the left lower end point (LL), wherein the vertical left line is curved due to the presence of the patient, wherein the analysis unit is configured to calculate a vertical right line between the right upper end point (RU) and the right lower end point (RL), wherein the vertical right line is curved due to the presence of the patient, wherein the analysis unit is configured to calculate a first intersection point (PI) between the detected course of the laser line and the calculated vertical left line, wherein the analysis unit is configured to calculate a second intersection point (P2) between the detected course of the laser line and the calculated vertical right line, wherein the analysis unit is configured to calculate a left angle between a line segment from the left upper end point (LU) to the calculated first intersection point (PI) and a line segment from the calculated first intersection point (PI) to the left lower end point (LL), wherein the analysis unit is configured to calculate a right angle between a line segment from the right upper end point (RU) to the calculated second intersection point (P2) and a line segment from the calculated second intersection point (P2) to the right lower end point (RL), wherein the analysis unit is configured to determine whether the left angle and the right angle are equal.

5. The optical device according to claim 4, wherein the generated feedback signal is implemented as a control signal configured to control the patient position and / or the patient rotation of the patient based on a difference between the left angle and the right angle determined by the analysis unit.

6. The optical device according to claim 1 or 2, wherein the analysis unit is configured to detect a gap in the course of the laser line, the gap being due to the presence of the patient, wherein the analysis unit is configured to detect a left end point (L) of the patient using a line detection algorithm, wherein the left end point (L) corresponds to a left point on the course of the laser line at which a horizontal portion of the laser line ends, wherein the analysis unit is configured to detect a right end point (R) of the patient using the line detection algorithm, wherein the right end point (R) corresponds to a right point on the course of the laser line at which a horizontal portion of the laser line ends, wherein spatial coordinates of the vertical center line of the X-ray sensor are stored in the optical device, wherein the analysis unit is configured to calculate a midpoint between the left end point (L) and the right end point (R), wherein the analysis unit is configured to calculate whether the midpoint lies on the vertical center line of the X-ray sensor.

7. The optical device according to claim 6, wherein the generated feedback signal is implemented as a control signal configured to control the determined patient position based on a difference between the midpoint and the vertical center line of the X-ray sensor calculated by the analysis unit.

8. The optical device according to claim 1 or 2, wherein the analysis unit is configured to detect a gap in the course of the laser line, the gap being due to a shape of the patient using a line detection algorithm, wherein the analysis unit is configured to determine a length of the gap of the course of the laser line at a left end position of the patient and at a right end position of the patient using a line detection algorithm, and wherein the analysis unit is configured to calculate the patient rotation from the determined length of the left end position of the patient and from the determined length of the right end position of the patient.

9. The optical device according to claim 8, wherein The feedback signal is implemented as a control signal configured to control the determined patient rotation based on a gap difference between a length of a left end position of the patient and a length of the right end position of the patient.

10. The optical device of claim 1 or 2, wherein The analysis unit is configured to detect an inhalation state of the patient, and wherein the analysis unit is configured to determine the inhalation state after determining the patient position and after determining that the patient position corresponds to the predetermined reference parameter.

11. A system for controlling a patient position and / or a patient rotation of a patient to be X-ray irradiated by an X-ray device, the system comprising: the X-ray device for generating an X-ray image of the patient, the X-ray device comprising an X-ray source and an X-ray sensor, the optical device of any one of claims 1 to 10, and wherein the system is configured to control the patient position and / or the patient rotation of the patient based on the feedback signal generated by the optical device.

12. The system of claim 11, wherein, the optical device is configured to determine an inhalation state of the patient, and wherein the system is configured to trigger a start of an X-ray imaging procedure based on a result of the inhalation state detection performed by the optical device.

13. A method for determining a patient position and / or a patient rotation of a patient to be X-ray irradiated with an X-ray system, the method comprising the following steps: emitting a horizontal laser line onto the patient by a laser source, detecting a course of the laser line on the patient by a detector, wherein the detector and the laser source are vertically spaced apart from each other, determining the patient position and / or the patient rotation based on an analysis of the detected course of the laser line by an analysis unit, verifying by the analysis unit whether the determined patient position and / or patient rotation corresponds to a predetermined reference parameter, providing a feedback signal by the analysis unit based on a result of the verification, wherein a spatial coordinate of a vertical centerline of an X-ray sensor of the X-ray system is stored, wherein the determined patient position and / or patient rotation is compared by the analysis unit to the stored spatial coordinate, and wherein the vertical centerline of the X-ray sensor is the reference parameter.

14. The method of claim 13, further comprising the following steps: controlling the patient position and / or patient rotation using the feedback signal configured as a control signal, wherein the control signal is received by a patient positioning system for changing the patient position and / or patient rotation upon receipt of the control signal.

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