Respiratory movement detection system and diagnostic bed sag correction method

Abstract

The invention discloses a respiratory movement detection system and a diagnostic bed sag correction method. The respiratory movement detection system comprises a diagnostic bed and a bed board arranged at the top of the diagnostic bed. A first detection device is arranged at one end of the bed board; a scanning controller is arranged at one end of the diagnostic bed; a second detection device is arranged at the other end of the diagnostic bed; the first detection device and the second detection device are electrically connected with the scanning controller; the respiratory movement detection data is used for CT 4D scanning, the sag detection data is used for respiratory movement curve correction and image reconstruction position correction, the two movement detection devices form a respiratory movement detection and diagnostic bed sag correction system, on one hand, the precision of the respiratory movement curve is improved, and on the other hand, the precision of the image reconstruction position is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of medical devices, and particularly to a respiratory movement detection system and a method for correcting the sag of a diagnostic bed. Background Art

[0002] Respiratory gating scanning requires detecting the respiratory change pattern of a patient, and the detection device should not affect normal scanning. If the detection device is close to or in contact with the chest and abdomen, materials with high X-ray attenuation (such as metal) should not be introduced to affect scanning.

[0003] There are several existing detection methods:

[0004] 1. The patient wears an elastic band, and the detection device detects the change of the elastic band.

[0005] 2. The patient wears a respiratory mask, and the detection device detects the change of respiratory airflow.

[0006] 3. A laser is aligned with the respiratory part to detect the change of the measured distance.

[0007] 4. Infrared body surface tracking is used to detect the change of the body surface area.

[0008] The method for sag correction is to use a sensor to detect the change of the sag of the diagnostic bed, and then through an electro-control mechanical structure, reverse movement is used to correct the sag of the bed board.

[0009] The existing methods cannot meet the usage requirements. The wearing experience of patients is not good, the debugging for doctors wearing is cumbersome, the cost of infrared body surface tracking is high, and the accuracy and stability are not high; in sag correction, the height of the bed is adjusted in real time during the operation of the diagnostic bed, which increases the electro-control mechanical structure, makes the system structure more complex, the correction effect depends on the control accuracy, and other errors may be introduced at the same time. Summary of the Invention

[0010] The purpose of the present invention is to provide a respiratory movement detection system and a method for correcting the sag of a diagnostic bed to solve the problems in the prior art.

[0011] To achieve the above object, the first technical solution adopted by the present invention is: a respiratory movement detection system, comprising: a diagnostic bed and a bed board arranged on the top of the diagnostic bed;

[0012] One end of the top of the bed board is provided with a first detection device;

[0013] One end of the diagnostic bed is provided with a scanning controller;

[0014] The other end of the diagnostic bed is provided with a second detection device;

[0015] The first detection device and the second detection device are both electrically connected to the scanning controller.

[0016] Preferably, there is also a shielding room. The diagnostic bed is arranged at the middle position inside the shielding room, and the second detection device is fixedly installed on the wall at the head end of the shielding room close to the diagnostic bed.

[0017] Preferably, the diagnostic bed is for the patient to lie flat, and a first detection mark is placed above the patient, and the first detection mark faces the first detection device.

[0018] Preferably, there is also a second detection mark, which is fixedly installed at the head of the diagnostic bed, and the second detection mark faces the second detection device.

[0019] Preferably, a rack is arranged between the second detection mark and the second detection device.

[0020] Preferably, the bed board can move horizontally, and the first detection device moves synchronously with the bed board.

[0021] To achieve the above object, the second technical solution adopted by the present invention is: a method for correcting the sag of a diagnostic bed, which is applied to a respiratory motion detection system, and includes the following steps:

[0022] Collect the motion state information of the first detection mark and the second detection mark based on a depth camera;

[0023] Establish the three-dimensional space coordinates (x, y, z) of the first mark and the second mark relative to the depth camera, where left and right are the X-axis, up and down are the Y-axis, and the distance from the first mark and the second mark to the depth camera is the Z-axis;

[0024] Place the first detection mark on the upper part of the patient's body surface, ensure that the first detection device faces the first detection mark, and record the change information of the three-dimensional space coordinates of the first mark;

[0025] Draw a respiratory motion curve based on the change information of the three-dimensional space coordinates of the first mark;

[0026] Obtain the diagnostic bed height information in real time based on the second mark, and analyze the diagnostic bed sag change information based on the diagnostic bed height information;

[0027] Generate correction information based on the diagnostic bed sag change information, correct the diagnostic bed height according to the correction information, and correct the reconstruction position during image reconstruction.

[0028] Preferably, the steps for generating the respiratory motion curve are as follows:

[0029] Collect the respiratory motion of several cycles and count the amplitude range of respiration;

[0030] Determine the display range of the curve. Among them, the maximum amplitude of the curve is Amax, and the minimum amplitude is Amin. Reserve a margin of 10 mm based on the maximum and minimum amplitudes to determine the display range ymax and ymin of the curve;

[0031] Within a sliding window, if the amplitude is greater than the threshold Tvalley, set the lowest point within the window as the trough; if the amplitude is less than the threshold Tpeak, set the highest point within the window as the peak;

[0032] Determine the respiratory motion cycle based on the corresponding moments of the peaks and troughs, and generate a respiratory motion curve.

[0033] Preferably, a scheme for image reconstruction is as follows:

[0034] Collect the change information of the second marker at the head of the diagnostic couch to form sag data, and send it to the scan controller;

[0035] The diagnostic couch sends the current position of the bed board to the scan controller;

[0036] The scan controller sends the received sag data and the bed board position as a data pair to the image reconstruction system;

[0037] The image reconstruction system receives the reconstruction position of the user, and based on the bed board position corresponding to the reconstruction position, queries and calculates the sag of the diagnostic couch, and uses the sag data to compensate the reconstruction position during image reconstruction.

[0038] Due to the application of the above technical solutions, the beneficial effects of this application compared with the prior art are as follows:

[0039] This application uses the respiratory motion detection data for CT 4D scanning, and the sag detection data for respiratory motion curve correction and also for image reconstruction position correction. The two sets of motion detection devices form a respiratory motion detection and diagnostic couch sag correction system, which improves the accuracy of the respiratory motion curve on the one hand and the accuracy of the image reconstruction position on the other hand. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for the description of the specific embodiments or the prior art.

[0041] Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other

[0042] drawings can also be obtained based on these drawings.

[0043] Figure 1 It is a schematic structural diagram of the respiratory motion detection system of the present invention;

[0044] Figure 2 Schematic diagram of the movement of the first detection device and the first detection mark in the breathing movement detection system of the present invention;

[0045] Figure 3 Schematic diagram of the deformation of the diagnostic bed board in the breathing movement detection system of the present invention;

[0046] Figure 4 Schematic diagram of the breathing movement curve in the breathing movement detection method of the present invention;

[0047] Figure 5 Flow chart for obtaining three-dimensional coordinates in the breathing movement detection method of the present invention;

[0048] Figure 6 Schematic diagram of image reconstruction in the breathing movement detection method of the present invention. Detailed implementation manners

[0049] In order to enable those skilled in the art to better understand the solutions of this application, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of this application. Obviously, the described embodiments are only a part of the embodiments of this application, rather than all the embodiments. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without making creative efforts shall fall within the protection scope of this application.

[0050] It should be noted that the terms "first", "second", etc. in the specification and claims of this application and the above-mentioned drawings are used to distinguish similar objects, and do not necessarily need to describe a specific order or sequence. It should be understood that such used data can be interchanged under appropriate circumstances for the embodiments of this application described herein. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device that includes a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0051] In this application, the orientation or positional relationship indicated by the terms "upper", "lower", "left", "right", "front", "rear", "top", "bottom", "inner", "outer", "middle", "vertical", "horizontal", "lateral", "longitudinal", etc. is based on the orientation or positional relationship shown in the accompanying drawings. These terms are mainly used to better describe the present invention and its embodiments, and are not used to limit that the indicated devices, elements or components must have a specific orientation, or be constructed and operated in a specific orientation.

[0052] Moreover, in addition to being used to represent orientation or positional relationships, some of the above terms may also be used to represent other meanings. For example, the term "upper" may also be used to represent a certain attachment relationship or connection relationship in some cases. For those of ordinary skill in the art, the specific meanings of these terms in the present invention can be understood according to specific circumstances.

[0053] In addition, the terms "installed", "set up", "provided with", "connected", "linked", "socketed" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral structure; it can be a mechanical connection or an electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, or there can be internal communication between two devices, components or parts. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0054] It should be noted that, without conflict, the embodiments in this application and the features in the embodiments can be combined with each other. The following will detail this application with reference to the accompanying drawings and in combination with the embodiments.

[0055] Embodiment 1

[0056] Figures 1 - 3 A respiratory movement detection system according to the present invention includes: a diagnostic bed and a bed board provided on the top of the diagnostic bed;

[0057] One end of the top of the bed board is provided with a first detection device;

[0058] One end of the diagnostic bed is provided with a scan controller;

[0059] The other end of the diagnostic bed is provided with a second detection device;

[0060] Both the first detection device and the second detection device are electrically connected to the scan controller.

[0061] According to an embodiment of the present invention, it further includes a shielding room. The diagnostic bed is arranged at the middle position inside the shielding room, and the second detection device is fixedly installed on the wall at the head end of the shielding room close to the diagnostic bed.

[0062] According to an embodiment of the present invention, the diagnostic bed is for the patient to lie flat, and a first detection mark is placed above the patient, and the first detection mark faces the first detection device.

[0063] According to an embodiment of the present invention, it further includes a second detection mark, which is fixedly installed at the head of the diagnostic bed, and the second detection mark faces the second detection device.

[0064] According to an embodiment of the present invention, a rack is arranged between the second detection mark and the second detection device.

[0065] According to an embodiment of the present invention, the bed board can move horizontally, and the first detection device moves synchronously with the bed board.

[0066] Embodiment 2

[0067] As Figures 4 - 6 shown, to achieve the above object, the second technical solution adopted by the present invention is: a method for correcting the sag of a diagnostic bed, applied to a respiratory motion detection system, including the following steps:

[0068] Collect the motion state information of the first detection mark and the second detection mark based on a depth camera;

[0069] Establish the three-dimensional space coordinates (x, y, z) of the first mark and the second mark relative to the depth camera, where left and right are the X-axis, up and down are the Y-axis, and the distance from the first mark and the second mark to the depth camera is the Z-axis;

[0070] Place the first detection mark on the upper part of the patient's body surface, ensure that the first detection device is facing the first detection mark, and record the change information of the three-dimensional space coordinates of the first mark;

[0071] Draw a respiratory motion curve based on the change information of the three-dimensional space coordinates of the first mark;

[0072] Obtain the diagnostic bed height information based on the second mark in real time, and analyze the diagnostic bed sag change information based on the diagnostic bed height information;

[0073] Generate correction information based on the diagnostic bed sag change information, correct the diagnostic bed height according to the correction information, and correct the reconstruction position during image reconstruction.

[0074] Specifically, the steps to obtain the three-dimensional coordinates of the detection mark are as follows:

[0075] Periodically collect depth images through a depth camera. The higher the collection frequency, the more accurate the motion detection;

[0076] Filter each collected image to remove background interference and ambient light interference;

[0077] Identify the mark and determine its position according to the characteristics of the mark;

[0078] Calculate the positions of each feature in the image to improve the position accuracy through multiple features;

[0079] Extract the three-dimensional space coordinates according to the position of the mark in the image.

[0080] According to an embodiment of the present invention, the steps for generating a respiratory motion curve are as follows:

[0081] Collect the respiratory motion for several cycles and count the amplitude range of breathing;

[0082] Determine the display range of the curve. Among them, the maximum amplitude of the curve is Amax, the minimum amplitude is Amin, and a 10-mm margin is reserved on the basis of the maximum and minimum amplitudes to determine the display range ymax and ymin of the curve;

[0083] Within a sliding window, if the amplitude is greater than the threshold Tvalley, set the lowest point within the window as the trough; if the amplitude is less than the threshold Tpeak, set the highest point within the window as the peak;

[0084] According to the corresponding moments of the peaks and troughs, determine the respiratory motion cycle and generate a respiratory motion curve.

[0085] Specifically, place the first detection marker on the upper part of the patient's body surface, ensure that the first detection device is directly facing the first detection marker, and record the change in the three-dimensional spatial coordinates of the first marker. Since respiratory motion mainly causes coordinate changes in the Y-axis direction, a respiratory motion curve is plotted with time t as the abscissa and the y component of the three-dimensional coordinates of the first detection marker as the ordinate.

[0086] According to the embodiment of the present invention, the deformation detection of the diagnostic couch bed board is as follows:

[0087] During the CT scanning process, the diagnostic couch bed board extends into the scanning hole. Due to the action of gravity, the diagnostic couch bed board bends downward, and the degree of deformation is called the sag.

[0088] The sag of the diagnostic couch not only affects the reference basis of the respiratory motion curve but also affects the position of the reconstructed image. Therefore, it is necessary to detect the sag of the diagnostic couch and correct the respiratory motion curve and the image reconstruction position.

[0089] The sag detection uses a motion detection device. The detection marker is installed at the head of the diagnostic couch, the detection device is directly facing the detection marker, the detection device is stationary relative to the couch body, and the change in the motion coordinates of the marker is collected.

[0090] Denote the detected respiratory amplitude as y, the sag as s, and k as the correction coefficient. Then

[0091] The corrected respiratory amplitude yc = y + k * s.

[0092] According to the embodiment of the present invention, an object is placed on the diagnostic couch bed board. During the scanning process, the object will move downward together with the bed board. On the reconstructed tomographic image, the scanned object will also move downward relative to the image center. To eliminate the influence of the sag of the diagnostic couch on the reconstruction position, it is necessary to correct the reconstruction position. The image reconstruction steps are as follows:

[0093] Collect the change information of the second marker at the head of the diagnostic couch to form sag data and send it to the scan controller;

[0094] The diagnostic bed sends the current position of the bed board to the scan controller;

[0095] The scan controller sends the received sag data and the bed board position as a data pair to the image reconstruction system;

[0096] The image reconstruction system receives the reconstruction position of the user, queries and calculates the sag of the diagnostic bed according to the bed board position corresponding to the reconstruction position, and uses the sag data to compensate the reconstruction position during image reconstruction.

[0097] In summary, in this application, the respiratory motion detection data is used for CT 4D scanning, and the sag detection data is used for respiratory motion curve correction and also for image reconstruction position correction. The two sets of motion detection devices form a respiratory motion detection and diagnostic bed sag correction system, which improves the accuracy of the respiratory motion curve on the one hand and the accuracy of the image reconstruction position on the other hand.

[0098] Finally, it should be noted that the above are only the preferred embodiments of the present invention and are not used to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements for some of the technical features. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A respiratory movement detection system, comprising: A diagnostic bed and a bed board arranged on the top of the diagnostic bed; characterized in that, One end of the top of the bed board is provided with a first detection device; One end of the diagnostic bed is provided with a scanning controller; The other end of the diagnostic bed is provided with a second detection device; Both the first detection device and the second detection device are electrically connected to the scanning controller.

2. The respiratory motion detection system according to claim 1, characterized in that: It further includes a shielding room. The diagnostic bed is arranged at the middle position inside the shielding room, and the second detection device is fixedly installed on the wall at the head end of the shielding room close to the diagnostic bed.

3. A respiratory motion detection system according to claim 2, characterized in that: The diagnostic bed is used for a patient to lie flat, and a first detection mark is placed above the patient, and the first detection mark is directly opposite to the first detection device.

4. The respiratory motion detection system according to claim 3, wherein: It further includes a second detection mark, which is fixedly installed at the head of the diagnostic bed, and the second detection mark is directly opposite to the second detection device.

5. The respiratory movement detection system according to claim 1, characterized in that: A rack is arranged between the second detection mark and the second detection device.

6. The respiratory movement detection system according to claim 5, characterized in that: The bed board can move in the horizontal direction, and the first detection device moves synchronously with the bed board.

7. A method for correcting the sag of a diagnostic bed, applied to the respiratory motion detection system according to claim 4, characterized in that, It includes the following steps: Collect the motion state information of the first detection mark and the second detection mark based on a depth camera; Establish the three-dimensional space coordinates (x, y, z) of the first mark and the second mark relative to the depth camera, where left and right are the X-axis, up and down are the Y-axis, and the distance from the first mark and the second mark to the depth camera is the Z-axis; Place the first detection mark on the upper part of the patient's body surface, ensure that the first detection device is directly opposite to the first detection mark, and record the change information of the three-dimensional space coordinates of the first mark; Draw a respiratory motion curve based on the change information of the three-dimensional space coordinates of the first mark; Obtain the diagnostic bed height information in real time based on the second mark, and analyze the diagnostic bed sag change information based on the diagnostic bed height information; Generate correction information based on the diagnostic bed sag change information, correct the diagnostic bed height according to the correction information, and correct the reconstruction position during image reconstruction.

8. The sag correction method of a diagnostic couch according to claim 7, characterized in that: The steps for generating the respiratory motion curve are as follows: Collect the respiratory motion of several cycles and count the amplitude range of respiration; Determine the display range of the curve. Among them, the maximum amplitude of the curve is Amax, the minimum amplitude is Amin, and a 10-mm margin is reserved on the basis of the maximum amplitude and the minimum amplitude to determine the display range ymax and ymin of the curve; Within a sliding window, if the amplitude is greater than the threshold Tvalley, set the lowest point within the window as the wave valley; if the amplitude is less than the threshold Tpeak, set the highest point within the window as the wave peak; Determine the respiratory motion cycle according to the corresponding moments of the wave peak and the wave valley, and generate a respiratory motion curve.

9. A method for correcting the sag of a diagnostic couch according to claim 7, characterized in that: The steps for image reconstruction are as follows: Collect the change information of the second marker at the head of the diagnostic bed to form sag data and send it to the scanning controller; The diagnostic bed sends the current position of the bed board to the scanning controller; The scanning controller sends the received sag data and the bed board position as a data pair to the image reconstruction system; The image reconstruction system receives the reconstruction position of the user, and queries and calculates the sag of the diagnostic bed according to the bed board position corresponding to the reconstruction position, and compensates the reconstruction position with the sag data when reconstructing the image.

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