A CT scanning auxiliary method

Abstract

The present invention provides a CT scanning auxiliary method, comprising: controlling two laser radars to respectively collect the distances of each target point in a preset scanning channel in a first direction and a second direction, and obtaining at least two groups of raw data; the preset scanning channels of the two laser radars cover the scanning field of view of the CT machine, and the second direction is perpendicular to the first direction; judging whether the scanned target is truncated in the first direction and the second direction according to the data symmetry of each group of raw data; if the scanned target is truncated in the first direction and / or the second direction, sending a first indication signal, the first indication signal comprising: moving the scanned target along the first direction, and / or adjusting the CT machine height along the second direction. The present invention can avoid human errors in the CT scanning process, and is more conducive to doctor's diagnosis.

Description

Technical Field

[0001] The present invention relates to the technical field of medical computer tomography, and in particular to a CT scanning auxiliary method. Background Art

[0002] CT (Computed Tomography), also known as computer tomography equipment. In the CT imaging process, there is a concept of scanning field of view. That is, if the scanned object exceeds the scanning field of view, the data will be "truncated". According to the CT imaging principle, if this situation is not handled, image truncation artifacts will appear.

[0003] In the prior art, the internal programs of CT machines are all equipped with truncation correction algorithms for correcting image truncation artifacts. The methods are similar, that is, "expanding" the data to obtain data reconstruction that satisfies the CT imaging model. However, such correction methods are all based on interpolation operations, which will cause loss of image resolution in the part where data truncation occurs. Therefore, there is an urgent need to provide a method that can avoid scanning data truncation in advance.

[0004] Currently, before entering the spiral tomography scan, doctors use their experience to judge whether the patient's scanned area will be truncated. However, this method is subject to human error. Summary of the invention

[0005] The purpose of the present invention is to provide a CT scanning auxiliary method, which can solve at least one of the above-mentioned technical problems. The specific solution is as follows:

[0006] The present invention provides a CT scanning auxiliary method, comprising:

[0007] The CT machine enters a flat scanning state, and simultaneously controls two laser radars located on the rotating frame to respectively collect the distances of various target points in the preset scanning channels in the first direction and the second direction, so as to obtain at least two sets of raw data; wherein the preset scanning channels of the two laser radars cover the scanning field of view of the CT machine, and the second direction is perpendicular to the first direction;

[0008] According to the data symmetry of each set of original data, determining whether the scanned target is truncated in the first direction and the second direction;

[0009] If the scanned object is truncated in the first direction and / or the second direction, a first indication signal is sent, and the first indication signal includes: moving the scanned object along the first direction, and / or adjusting the CT machine height along the second direction.

[0010] Optionally, before the step of controlling the two laser radars on the rotating frame to respectively collect the distances of each target point in the preset scanning channels in the first direction and the second direction, the method further includes:

[0011] The central scanning channel light rays of the two laser radars are preset to pass through the center of the scanning field of view.

[0012] Optionally, the two laser radars located on the rotating frame are controlled to respectively collect the distances of each target point in the preset scanning channels in the first direction and the second direction to obtain at least two sets of raw data, including:

[0013] Controlling a first laser radar located on the inner wall of the rotating frame and having a central scanning channel in the second direction, collecting distances of various target points in the preset scanning channel in the first direction at fixed intervals during a flat scanning process of the CT machine tool, and obtaining multiple groups of first original data;

[0014] At the same time, a second laser radar located on the inner wall of the rotating frame and having a central scanning channel in the first direction is controlled to collect the distance of each target point in the preset scanning channel in the second direction at fixed intervals during the CT machine tool scanning process to obtain multiple groups of second original data.

[0015] Optionally, judging whether the scanned target will be truncated in the first direction and the second direction according to the data symmetry of each set of original data includes:

[0016] Determine whether two edge channel data in each group of first original data and each group of second original data are symmetrical, wherein the two edge channels correspond to two edges of the scanning field of view respectively;

[0017] If the two edge channel data in each set of first original data and each set of second original data are symmetrical, it is determined that the scanned object will not be truncated; or,

[0018] If two edge channel data of any group of first original data or second original data are asymmetric, it is determined that the scanned object will be truncated.

[0019] Optionally, the method further includes: if the scanned target is not truncated in both the first direction and the second direction, sending a second indication signal, the second indication signal including adjusting the CT machine height along the second direction, and / or moving the scanned target along the first direction so that the scanned target is located at the center of the scanning field of view of the CT machine.

[0020] Optionally, the method further includes: in response to the operation instruction of selecting to adjust the CT machine height along the second direction, acquiring a current channel of the scanned object in the second direction according to at least one set of raw data collected in a preset scanning channel in the second direction;

[0021] According to the size of the scanned target and the preset scanning channel of the laser radar corresponding to the second direction, a target channel of the scanned target in the second direction is obtained;

[0022] Subtract the corresponding values ​​of the current channel from those of the target channel to obtain a target value; and control the CT machine tool to increase or decrease the target value along the second direction.

[0023] Optionally, before subtracting the corresponding values ​​of the current channel from the target channel, the method further includes:

[0024] Determining whether the target channel is within the scanning field of view of the CT machine;

[0025] If it is within the scanning field of view of the CT machine, the CT machine bed is controlled to rise or fall along the second direction.

[0026] Optionally, the method further includes: if the target channel is not within the scanning field of view of the CT machine, recalculating the target channel so that the target channel is within the scanning field of view of the CT machine.

[0027] Optionally, after controlling the CT machine to raise or lower the target value along the second direction, the method further includes: controlling the CT machine to enter a spiral scanning state to acquire a tomographic image.

[0028] Optionally, the method further includes: if the scanned target is truncated in the first direction and / or the second direction, and the size of the scanned target exceeds the scanning field of view of the CT machine, locating the abnormal part in the scanned target and controlling the abnormal part to be close to the center of the scanning field of view of the CT machine.

[0029] Compared with the prior art, the above solution of the embodiment of the present invention has at least the following beneficial effects:

[0030] First, the CT scanning auxiliary method provided by the present invention collects human body data through two laser radars arranged on a rotating frame before entering the spiral tomography scan, and calculates whether the scanned target is truncated based on the collected data. It has strong objectivity and high accuracy, can avoid human errors, and provide a reliable basis for subsequent doctor's diagnosis.

[0031] Second, regardless of whether the data is truncated or not, by adjusting the CT bed height in the second direction and / or moving the scanned target along the first direction, the scanned target is moved to the center of the scanning field of view, which can further improve the image resolution of the scanned target and is more conducive to diagnosis by medical staff. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The drawings herein are incorporated into and constitute a part of the specification, showing embodiments consistent with the present invention, and together with the specification, are used to explain the principles of the present invention. Obviously, the drawings described below are only some embodiments of the present invention, and for those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative work. In the drawings:

[0033] Figure 1 A flow chart of a CT scanning auxiliary method provided by an embodiment of the present invention is shown;

[0034] Figure 2 A schematic diagram showing truncation of a scanned object provided by an embodiment of the present invention is shown;

[0035] Figure 3 A schematic diagram showing a scanned object without being truncated provided by another embodiment of the present invention;

[0036] Figure 4 A flow chart of a method for controlling two laser radars located on a rotating frame to respectively collect the distances of various target points in a preset scanning channel in a first direction and a second direction to obtain at least two groups of raw data provided by an embodiment of the present invention is shown;

[0037] Figure 5 A schematic diagram of a curve showing a set of channel numbers and distances collected by a first laser radar in a first direction provided by an embodiment of the present invention is shown;

[0038] Figure 6 A schematic diagram of a curve showing a set of channel numbers and distances collected by a second laser radar in a second direction provided by an embodiment of the present invention is shown;

[0039] Figure 7 A flow chart of a method for determining whether a scanned target will be truncated in the first direction and the second direction according to the data symmetry of each group of original data provided by an embodiment of the present invention is shown;

[0040] Figure 8 A flow chart of a method for automatically adjusting the bed height along a second direction by a system provided by an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0041] In order to make the purpose, technical scheme and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0042] The terms used in the embodiments of the present invention are only for the purpose of describing specific embodiments, and are not intended to limit the present invention. The singular forms "a", "said" and "the" used in the embodiments of the present invention and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings, and "multiple" generally includes at least two.

[0043] It should be understood that the term "and / or" used in this article is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0044] It should be understood that although the terms first, second, third, etc. may be used to describe the embodiments of the present invention, they should not be limited to these terms.

[0045] It should also be noted that the term "includes", "comprising" or any other variation thereof is intended to cover non-exclusive inclusion, so that a commodity or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such commodity or device. In the absence of more restrictions, the elements defined by the sentence "comprising a ..." do not exclude the existence of other identical elements in the commodity or device including the elements.

[0046] The optional embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0047] The CT (computed tomography) scanning auxiliary method provided by the present invention is applied when the CT machine is in a plain scanning state and the frame has not yet rotated. It can judge in advance whether the scanned target will be truncated and solve it, thereby providing a good foundation for the subsequent spiral tomography imaging of the CT machine and preventing the spiral scanning image from being truncated.

[0048] Specifically, Figure 1 FIG. 2 is a flow chart of a CT scanning auxiliary method provided by an embodiment of the present invention. Figure 1 As shown, the CT scanning auxiliary method includes:

[0049] S10, the CT machine enters a plain scanning state, and simultaneously controls two laser radars located on the rotating frame to respectively collect the distances of various target points in the preset scanning channels in the first direction and the second direction, to obtain at least two sets of raw data; wherein the preset scanning channels of the two laser radars cover the scanning field of view of the CT machine, and the second direction is perpendicular to the first direction;

[0050] The first direction is the horizontal direction, namely the X direction, the second direction is the direction perpendicular to the horizontal direction, namely the Y direction, the length direction of the CT machine tool is the Z direction, and an XYZ coordinate system is established, which satisfies the right-hand system definition.

[0051] The two laser radars include a first laser radar and a second laser radar, and the central scanning channel light of the first laser radar passes through the center of the scanning field of view, while the central scanning channel light of the second laser radar passes through the center of the scanning field of view. It can be understood that the central light emitted by the first laser radar passes through the center of the scanning field of view of the CT machine in the second direction (Y direction), and the central light emitted by the second laser radar passes through the center of the scanning field of view of the CT machine in the first direction (X direction). In this embodiment, Figure 2-3 As shown, the first laser radar is fixed to the top of the inner wall of the rotating frame of the CT machine, and is used to scan various target points in the first direction; the second laser radar is fixed to the side of the inner wall of the rotating frame of the CT machine, and is used to scan various target points in the second direction.

[0052] The first laser radar and the second laser radar correspond to a preset scanning channel respectively, and the preset scanning channel refers to the preset scanning range of the laser radar, and the preset scanning channel includes the total number of scanning channels and the channel interval. For example, the channel interval of the first laser radar is set to 1mm, and 1000 channels are scanned at a time, then 1000 channels cover a scanning range of 1000mm, that is, each scan can obtain the original data of 1000 channels in the first direction. The central scanning channel refers to the middle value of the total number of channels, for example, there are 1000 scanning channels, and the central scanning channel is the 500th channel.

[0053] The first laser radar and the second laser radar work independently of each other. Taking the first laser radar as an example, the first laser radar uses laser as a signal source. The pulse laser emitted by the laser hits an object and causes scattering. Part of the light wave will be reflected to the laser radar receiver. According to the laser ranging principle, the distance from the laser radar to the target point is calculated. The pulse laser continuously scans the target object, and the data of all target points on the target object in the first direction can be obtained.

[0054] Each CT machine has a scanning field of view, and the scanning field of view plane can be considered to be circular. During the CT scanning process, the scanned target needs to be within the scanning field of view to avoid truncation. Since the longitudinal cross-section of the human body is approximately elliptical, the present invention sets two laser radars to determine whether truncation occurs from the X and Y directions to improve the accuracy of judgment. Specifically, the range of the preset scanning channel of the first laser radar is greater than or equal to the scanning field of view in the first direction, and the range of the preset scanning channel of the second laser radar is greater than or equal to the scanning field of view in the second direction. In this embodiment, the range of the preset scanning channel of the first laser radar is equal to the scanning field of view in the first direction, and the range of the preset scanning channel of the second laser radar is equal to the scanning field of view in the second direction. At this time, the two end channels of the preset scanning channels of the first laser radar and the second laser radar are regarded as their respective edge channels. For example, the preset scanning channel of the first laser radar is 1-500mm, and the scanning field of view is 500mm, then the two edge channels are evaluated as the first channel and the 500th channel.

[0055] In other optional embodiments, the range of the preset scanning channel of the first laser radar is larger than the scanning field of view in the first direction, and the range of the preset scanning channel of the second laser radar is larger than the scanning field of view in the second direction, so that the complete data of the scanned target in the X and Y directions can be obtained at one time, which is convenient for calculation. In this embodiment, the edge channel of the first laser radar and the edge channel of the second laser radar need to be preset. The edge channels are the two edges of the scanning field of view, which can be evaluated specifically through geometric relationships. For example, the preset scanning channel of the first laser radar is 1-1000mm, and the scanning field of view is 500mm, then the edge channels are evaluated as the 250th channel and the 750th channel.

[0056] In this embodiment, Figure 4 As shown, the step S10 specifically includes:

[0057] S11, controlling a first laser radar located on a rotating frame and having a central scanning channel that coincides with the second direction, to collect distances of various target points in a preset scanning channel in the first direction at each fixed interval during a flat scanning process, and obtain multiple sets of first raw data;

[0058] S12, simultaneously controlling a second laser radar located on a rotating frame and having a central scanning channel that coincides with the first direction, to collect the distance of each target point in a preset scanning channel in the second direction at each fixed interval during the flat scanning process, and obtain multiple sets of second original data.

[0059] In actual application, when the patient lies on the machine tool, the machine tool moves horizontally at a uniform speed into the frame for a flat scan. At this time, the tube is located at the lowest end of the frame to obtain an X-ray flat film image; at the same time, the first laser radar at an angle of 180 degrees to the tube is controlled to start emitting laser. When there is a scanned object on the scanning channel, the laser hits the target point of the scanned object and is received. When there is no scanned object on the scanning channel, the laser hits the inner wall of the frame and is received, thereby generating the first group of first original data; because the machine tool is moving along the Z direction, after moving at an interval of 2mm, the second group of first original data is collected, and so on, n groups of first original data are obtained, where n is greater than or equal to 1, Figure 5 Only a set of curve diagrams of the number of channels and distance collected by the first laser radar in the first direction are shown. Similarly, the second laser radar at a 90-degree angle to the tube is controlled to scan and obtain m sets of second raw data, where m is greater than or equal to 1. Figure 6 Only a set of curve diagrams of the number of channels and distances collected by the second laser radar in the second direction are shown.

[0060] S20, judging whether the scanned target will be truncated in the first direction and the second direction according to the data symmetry of each set of original data;

[0061] In this step, the n groups of first original data are judged respectively, and the m groups of second original data are judged at the same time. Only when all the data are not truncated, it is considered that the scanned object will not be truncated. Specifically, in the embodiment of the present invention, if Figure 7 As shown, the step S20 includes:

[0062] S21, respectively determining whether two edge channel data in each group of first original data and each group of second original data are symmetrical, wherein the two edge channels respectively correspond to two edges of the scanning field of view;

[0063] S22, if the two edge channel data in each group of first original data and each group of second original data are symmetrical, it is determined that the scanned target will not be truncated; or, if the two edge channel data in any group of first original data or second original data are asymmetrical, it is determined that the scanned target will be truncated.

[0064] like Figure 5 As shown, the two edge channel data of a group of first raw data of the first laser radar are the same, and at this time, it is considered that the scanning position corresponding to the group of first raw data is within the scanning field of view; and as shown Figure 6 As shown, if the two edge channel data of a set of second raw data of the second laser radar are different, it is considered that the scanning position corresponding to the set of second raw data is not within the scanning field of view. Figure 5 and Figure 6It can be seen from the raw data in two directions that the scanned target will be truncated at the current position. Of course, the two edge channel data are close and can also be considered symmetrical, for example, the distance between the two edge channels differs by a specific threshold, and the specific threshold is set according to actual needs.

[0065] It should be noted that when the range of the preset scanning channel of the first laser radar is equal to the scanning field of view in the first direction, and the range of the preset scanning channel of the second laser radar is equal to the scanning field of view in the second direction, if the scanned target is truncated, the raw data obtained by the laser radar at this time is incomplete, and the unscanned data needs to be supplemented according to the data symmetry when the current channel of the scanned target is subsequently acquired. Of course, other methods such as expanding the preset scanning channel and rescanning can also be used to scan the complete raw data.

[0066] S30, if the scanned object is truncated in the first direction and / or the second direction, a first indication signal is sent, wherein the first indication signal includes: moving the scanned object along the first direction; and / or adjusting the CT machine height along the second direction.

[0067] In this step, when the system determines that the data is truncated, a corresponding indication signal is given for each truncation method so that the medical worker can make a selection, and in response to the user's selection, a corresponding operation is performed. Specifically, if the scanned object is truncated in the first direction and / or the second direction, a first indication signal is sent, including:

[0068] (1) when the scanned object is not truncated in the first direction but is truncated in the second direction, sending an instruction signal for adjusting the height of the CT machine tool along the second direction, or sending an instruction signal for moving the scanned object along the first direction and adjusting the height of the CT machine tool along the second direction; or,

[0069] (2) when the scanned object is truncated in the first direction and not truncated in the second direction, sending an instruction signal to move the scanned object along the first direction, or sending an instruction signal to move the scanned object along the first direction and adjust the CT machine height along the second direction; or,

[0070] (3) When the scanned object is truncated in both the first direction and the second direction, an instruction signal is sent to move the scanned object along the first direction and to adjust the height of the CT machine tool along the second direction.

[0071] For any indication signal, when the system determines that the data is truncation, it will calculate the direction and height of the machine tool, or the distance to move left or right along the first direction, and send the information to the computer. The system can provide prompts in the form of pop-up windows for medical staff to choose. When the user selects any operation, the pop-up window disappears.

[0072] For the prompt of moving the scanned object along the first direction, the medical staff can only be advised to move the patient manually. Of course, if the machine tool moves along the first direction, the system can also realize the movement of the scanned object along the first direction through automation.

[0073] For the prompt of adjusting the CT machine bed height along the second direction, the medical staff can choose whether to adjust the bed height, and whether to choose manual adjustment or automatic adjustment by the system. If manual adjustment is selected, the medical staff will manually adjust the bed height according to the prompt information, and if automatic adjustment is selected, the system will receive the selection instruction and automatically perform the adjustment.

[0074] In other optional embodiments, if the scanned target is not truncated in the first direction and the second direction, the system will generate a second indication signal, and the second indication signal includes adjusting the CT machine height along the second direction, and / or moving the scanned target along the first direction so that the scanned target is located at the center of the scanning field of view of the CT machine.

[0075] It should be noted that: when data truncation occurs on the scanned object, the purpose of sending the first instruction signal to move the scanned object and / or adjust the bed height is to prevent the scanned object from being truncation and to improve the resolution of the spiral scanning image. When data truncation does not occur on the scanned object, the purpose of sending the second instruction signal is to further improve the resolution of the spiral scanning image on the basis of no truncation.

[0076] The following describes in detail how the system automatically adjusts the bed height along the second direction. Figure 8 As shown, specifically including:

[0077] S31, in response to the operation instruction of selecting to adjust the CT machine height along the second direction, acquiring the current channel of the scanned object in the second direction according to the acquired raw data in the preset scanning channel in the second direction;

[0078] The current channel is the height of the scanned target in the second direction, which is represented by a channel value. For example, if the height of the scanned target is 100 mm, the current channel [250, 350] indicates that the scanned target is located between the 250th channel and the 350th channel in the second direction. In this embodiment, since multiple sets of second original data are collected, the current channel can be obtained by averaging the data of the same channel collected multiple times as the distance of the target point on the channel based on the symmetry of the averaged multiple data.

[0079] If the preset scanning channels in the first direction and the second direction are equal to the scanning field of view, since the longitudinal cross-section of the human body is regarded as an ellipse, which is a symmetrical figure, each set of collected raw data can be supplemented according to the data symmetry, for example Figure 7 The missing original data in the image is supplemented by the symmetry of the data to obtain the complete data of the scanned target, thereby obtaining the current channel of the scanned target.

[0080] S32, obtaining a target channel of the scanned target in the second direction according to the size of the scanned target and a preset scanning channel of the laser radar corresponding to the second direction;

[0081] Among them, determined by the CT imaging principle, the closer the scanned target is to the rotation center, the higher the image resolution is. Therefore, the target channel is the center of the scanned target with the center of the scanning field of view as the center, and the width of the scanned target in the second direction, i.e., the target channel, is obtained.

[0082] S33, obtaining a target value by subtracting the corresponding values ​​of the current channel and the target channel, and controlling the CT machine tool to raise or lower the target value along the second direction, so that the scanned target moves from the current channel along the second direction to a position in the same first direction as the target channel.

[0083] Specifically, the target value may be zero, a positive number or a negative number. If the target value is a positive number, the machine tool is controlled to increase the target value; if the target value is a negative number, the machine tool is controlled to decrease the target value; if the target value is zero, the bed height is kept unchanged.

[0084] In practical applications, if the scanning field of view of the CT machine is 500mm, the channel interval of the second laser radar is 1mm, and the preset scanning channel is 1000, ideally, the scanned target is within the channel range of the original data [250, 750] in the second laser radar, indicating that the scanned part is within the scanning field of view and no data truncation occurs; when it is not within the channel range of [250, 750], it indicates that data truncation occurs. At this time, it is necessary to ensure that the scanned target is not truncated and the image resolution is high, specifically including moving the scanned target from the current channel along the first direction and / or the second direction to the target channel.

[0085] For example, when the scanned target is a spherical object with a diameter of 100mm, the current channel in the second direction is [350, 450]. Since the scanning channel is 1000mm and the center is 500mm, the spherical object with a diameter of 100mm is placed at 500mm as the center. The two sides of the object are 50mm away from the center, that is, the target channel is [450, 550]. The difference between 450mm and 350mm in the second direction is 100mm. Then, by raising the bed by 100mm, the scanned target can be moved to the same horizontal direction as the center of the scanning field of view. At this time, if the scanned target is not yet at the center of the scanning field of view in the first direction, the distance and direction of movement along the first direction will continue to be calculated, and prompts will be given to medical staff to suggest moving the patient along the first direction.

[0086] Furthermore, before subtracting the corresponding values ​​of the current channel from the target channel to obtain a target value, the method further includes: determining whether the target channel is within the scanning field of view of the CT machine;

[0087] If it is within the scanning field of view of the CT machine, continue to execute step S33; or,

[0088] If it is not within the scanning field of view of the CT machine, the target channel is recalculated so that the target channel is within the scanning field of view of the CT machine and close to the center of the scanning field of view.

[0089] Specifically, the system will automatically determine whether the size of the current scanned object can meet the requirement of no data truncation under ideal conditions; if there is a situation where no truncation is required, the bed height will be adjusted appropriately to ensure that the object data channel is within the channel range of [250,750]; if the adjustment of the bed height triggers truncation, the system will automatically stop at the optimal position allowed without truncation. The optimal position can be determined based on the channel interval, starting from the first determined target channel and moving away from the target channel in sequence, until the re-determined current target channel is not truncation and is closest to the center of the scanning field of view.

[0090] Furthermore, the CT machine scanning auxiliary method provided by the present invention also includes: after executing the corresponding operation in response to the selection instruction of the first indication signal or the second indication signal, controlling the CT machine to enter the spiral scanning state to obtain a tomographic scan image.

[0091] Specifically, after the flat scanning state ends, the scanned target will not be truncated. At this time, the CT machine enters the spiral scanning state. At this time, the two laser radars stop working and enter the standby state. The two laser radars rotate with the rotating frame until the next flat scanning state is entered, and then the two laser radars are woken up.

[0092] In other optional embodiments, the method further includes:

[0093] If the scanned target is truncated in the first direction and / or the second direction, and the size of the scanned target exceeds the scanning field of view of the CT machine, the abnormal part in the scanned target is located and controlled to be close to the center of the scanning field of view of the CT machine.

[0094] In actual applications, in addition to unreasonable patient positioning and human error causing data truncation during scanning, there is another situation where truncation occurs: for scanned objects whose size is larger than the scanning field of view, such as obese people, truncation will occur at any position. In this way, the X-ray plain film image can be used to locate abnormal parts of the scanned object, such as tumors, hyperplasia, etc., and the machine tool can be adjusted along the second direction to the bed height corresponding to the abnormal part and / or the scanned object can be moved along the first direction so that the abnormal part is located in the center of the scanning field of view, and the truncation correction process is turned on at the same time to improve the resolution of the scanned image.

[0095] The CT scanning auxiliary method provided by the present invention collects human body data through two laser radars arranged on a rotating frame before entering the spiral tomography scan, and calculates whether the scanned target is truncated based on the collected data. The method has strong objectivity and high accuracy, can avoid human errors, and provide a reliable basis for subsequent doctor's diagnosis; while ensuring that the data is not truncated, the system can further adjust the CT bed height and / or move the scanned target, and move the scanned target to the center of the scanning field of view. Compared with the existing CT scanning, under the same dose conditions, the image resolution of the scanned target is improved, which is more conducive to the diagnosis of medical staff.

[0096] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A CT scanning auxiliary method, characterized in that: include: The CT machine enters a plain scan state, and simultaneously controls two laser radars located on a rotating frame to respectively collect distances of various target points in a first direction and a second direction of preset scanning channels, to obtain at least two sets of raw data; wherein the preset scanning channels of the two laser radars cover the scanning field of view of the CT machine, and the second direction is perpendicular to the first direction; the first direction is a horizontal direction, i.e., an X direction, and the second direction is a direction perpendicular to the horizontal direction, i.e., a Y direction, and the length direction of the CT machine is a Z direction, and an XYZ coordinate system is established, and the XYZ coordinate system satisfies the right-hand system definition; According to the data symmetry of each set of original data, determining whether the scanned target is truncated in the first direction and the second direction; If the scanned object is truncated in the first direction and / or the second direction, a first indication signal is sent, wherein the first indication signal includes: moving the scanned object along the first direction, and / or adjusting the CT machine height along the second direction; Before the step of controlling the two laser radars on the rotating frame to respectively collect the distances of each target point in the preset scanning channels in the first direction and the second direction, the method further includes: Preset the central scanning channel light of the two laser radars to pass through the center of the scanning field of view; The two laser radars located on the rotating frame are controlled to respectively collect the distances of each target point in the preset scanning channels in the first direction and the second direction to obtain at least two sets of raw data, including: Controlling a first laser radar located on the inner wall of the rotating frame and having a central scanning channel in the second direction, collecting distances of various target points in the preset scanning channel in the first direction at fixed intervals during a flat scanning process of the CT machine tool, and obtaining multiple groups of first original data; At the same time, a second laser radar located on the inner wall of the rotating frame and having a central scanning channel in the first direction is controlled to collect the distance of each target point in the preset scanning channel in the second direction at fixed intervals during the CT machine tool flat scanning process to obtain multiple sets of second original data; The step of judging whether the scanned target will be truncated in the first direction and the second direction according to the data symmetry of each set of original data includes: Determine whether two edge channel data in each group of first original data and each group of second original data are symmetrical, wherein the two edge channels correspond to two edges of the scanning field of view respectively; If the two edge channel data in each set of first original data and each set of second original data are symmetrical, it is determined that the scanned object will not be truncated; or, If two edge channel data of any group of first original data or second original data are asymmetric, it is determined that the scanned object will be truncated.

2. The method according to claim 1, characterized in that The method further comprises: If the scanned target is not truncated in the first direction and the second direction, a second indication signal is sent, wherein the second indication signal includes adjusting the CT machine height along the second direction and / or moving the scanned target along the first direction so that the scanned target is located at the center of the scanning field of view of the CT machine.

3. The method according to any one of claims 1-2, characterized in that: The method further comprises: In response to the operation instruction of selecting to adjust the CT machine height along the second direction, acquiring the current channel of the scanned object in the second direction according to at least one set of raw data acquired in the preset scanning channel in the second direction; Obtaining a target channel of the scanned target in the second direction according to the size of the scanned target and a preset scanning channel of the laser radar corresponding to the second direction; A target value is obtained by subtracting the corresponding values ​​of the current channel and the target channel; and the CT machine tool is controlled to increase or decrease the target value along the second direction.

4. The method according to claim 3, characterized in that Before subtracting the corresponding values ​​of the current channel from the target channel, the method further includes: Determining whether the target channel is within the scanning field of view of the CT machine; If it is within the scanning field of view of the CT machine, the CT machine bed is controlled to rise or fall along the second direction.

5. The method according to claim 4, characterized in that The method further comprises: If it is not within the scanning field of view of the CT machine, the target channel is recalculated so that the target channel is within the scanning field of view of the CT machine.

6. The method according to claim 3, characterized in that After controlling the CT machine tool to increase or decrease the target value along the second direction, the method further includes: The CT machine is controlled to enter a spiral scanning state to acquire a tomographic image.

7. The method according to claim 1, characterized in that The method further comprises: If the scanned target is truncated in the first direction and / or the second direction, and the size of the scanned target exceeds the scanning field of view of the CT machine, the abnormal part of the scanned target is located and controlled to be close to the center of the scanning field of view of the CT machine.

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