CN116196027A - CT scanning equipment and scanning method for reducing CT radiation by adaptive scanning area - Google Patents

Abstract

The application discloses a CT scanning device and a scanning method for reducing CT radiation in an adaptive scanning area. The CT scanning device includes: a CT main body, including a tube, a detector and a collimator; the collimator includes two collimators Straight blades, the two collimating blades can move along the X-axis direction, so that the distance between the two collimating blades can be adjusted; the bed board can be driven to enter the CT main body along the Z-axis, and the The bed board can be driven to move along the X-axis direction, so that the projection of the lesion position on the detector is located in the middle of the detector; the Z-axis is the pushing direction of the bed board, and the X-axis is horizontal direction and perpendicular to the Z axis. The present application solves the problem that when the scanning device in the related art scans a local organ, the patient will be exposed to redundant ray radiation, and since the imaging position of the local organ after scanning is located at the edge of the detector, the image quality is not good.

Description

CT scanning equipment and scanning method for reducing CT radiation by adaptive scanning area

technical field

The present application relates to the technical field of CT equipment, in particular, to a CT scanning equipment and a scanning method for reducing CT radiation by adaptively scanning an area.

Background technique

The image chain of traditional CT system is composed of tube, collimator, scanning table and detector. The ball tube, collimator and detector are integrated on the rotating part of the scanning frame to follow the rotation, and the scanning bed carries the patient to move in the Z direction. The scanning process can be simply described as, the tube emits X-rays, the collimator controls the fan angle of the rays, the rays pass through the patient lying on the bed, and the detector receives the rays to complete the scanning process.

The ray fan angle emitted by the tube is determined by the size of the slit of the blade in the collimator. The current design of the blade is mainly divided into two types:

1. It consists of two blades that can move independently in the Z direction, and the fan angle of rays passing through the collimator is controlled by the distance between the end faces of the blades.

2. It consists of a blade with multiple slits, and different widths correspond to different fan angles.

The scanning table needs to carry the patient to move to the scanning center, so that the lesion area is inside the scanning fan angle, so that the rays completely pass through the lesion to complete the scan. However, when scanning local organs such as the heart, lungs, and limbs, the lesion is located on one side of the patient, so the radiation on the other side does not play an imaging role, causing the patient to suffer from excess radiation, which endangers the patient's health, and due to local organ The imaging position after scanning is located at the edge of the detector, so the image quality is poor.

Contents of the invention

The main purpose of this application is to provide a CT scanning device to solve the problem that when the scanning device in the related art scans a local organ, the patient will bear redundant radiation radiation, and since the imaging position of the local organ after scanning is located at the detector edge, hence the problem of poor image quality.

In order to achieve the above object, the application provides a CT scanning device, the CT scanning device includes:

CT main body, including tube, detector and collimator;

The collimator includes two collimating blades, and the two collimating blades can move along the X-axis direction, so that the distance between the two collimating blades can be adjusted;

The bed board can be driven to enter the CT main body along the Z axis, and the bed board can be driven to move along the X axis direction, so that the projection of the lesion position on the detector is located in the middle of the detector;

The Z-axis is the pushing direction of the bed board, and the X-axis is horizontal and perpendicular to the Z-axis.

Further, the collimator also includes a top cover and a first driving assembly arranged on the top cover, the collimating blades are arranged on the top cover, and the first driving assembly is connected with the collimating blades , for driving the collimating blades to move along the X-axis direction.

Further, a slide rail is provided on the top cover along the X-axis direction, and the collimating blades are slidably arranged in the slide rail.

Further, the slide rail includes a first track bar and a second track bar, and slide grooves are opened on the opposite sides of the first track bar and the second track bar, and the two sides of the collimation blades are connected with the slide grooves. Swipe to connect.

Further, the first drive assembly includes a drive motor, a first connecting piece and a second connecting piece;

The output end of the drive motor is provided with a gear;

The first connecting piece is connected to one of the collimating blades, the second connecting piece is connected to the other of the collimating blades, and the first connecting piece is provided with a gear that meshes with the first side of the gear. The second connecting member is provided with a rack meshing with the second side of the gear.

Further, it also includes a base, on which a second driving assembly is arranged, and the second driving assembly is used to drive the bed board to move along the X-axis direction.

Further, the base includes a lifting assembly and a lower frame, and the lower end of the bed board is provided with an upper frame;

The lower frame is arranged at the output end of the lifting assembly, the second driving assembly is arranged in the lower frame, the upper frame is arranged on the lower frame and can move along the X-axis direction, and the second driving assembly is arranged in the lower frame. The second driving assembly is connected with the upper frame.

Further, the second drive assembly includes a linear motor, and the linear motor is in transmission connection with the upper frame.

According to another aspect of the present application, there is provided a scanning method for reducing CT radiation in an adaptive scanning area, using the above-mentioned CT scanning device, and the following steps:

Perform one or more scans and obtain scan results;

Calculate ROI section parameters and positions based on the scanning results;

Based on the ROI section parameter and position, determine the movement stroke of the bed board in the X-axis direction;

Based on the moving stroke, controlling the movement of the bed board so that the projection of the lesion position on the detector is located in the middle of the detector;

Based on the ROI section parameters and position, it is determined whether the small FOV scanning mode is satisfied, and if so, the distance between the two collimation blades is adjusted so that the scanning boundary fits the lesion section and the scanning is performed.

Further, based on the ROI section parameters and position, determine whether the small FOV scanning mode is satisfied, if not,

Adjust the collimating blades to move in the Z-axis direction and perform a scan.

In the embodiment of this application, by setting the CT main body, including the tube, the detector and the collimator; The distance between the straight blades is adjustable; the bed board can be driven to enter the CT main body along the Z axis, and the bed board can be driven to move along the X axis direction, so that the projection of the lesion position on the detector is located in the middle of the detector; The Z-axis is the pushing direction of the bed board, and the X-axis is the horizontal direction and is perpendicular to the Z-axis. By adjusting the position of the bed board in the X-axis direction, the lesion can be imaged in the middle of the detector after scanning, and by adjusting the two The distance between the collimating blades enables the scanning range of the rays passing through the collimating blades to match the lesion cross-section, thereby improving the image quality of the reconstruction mode and completing the local lesion area of the patient with a small scanning dose. scanning, reducing the technical effect of the radiation suffered by the patient, thereby solving the problem that when the scanning equipment in the related art scans the local organs, the patient will suffer from excess radiation, and because the imaging position of the local organs after scanning is located in the detection the edge of the monitor, so the problem of poor image quality.

Description of drawings

The accompanying drawings, which constitute a part of this application, are included to provide a further understanding of the application and make other features, objects and advantages of the application apparent. The drawings and descriptions of the schematic embodiments of the application are used to explain the application, and do not constitute an improper limitation to the application. In the attached picture:

Fig. 1 is a schematic diagram of the structure of the bed board not moving according to the embodiment of the present application;

Fig. 2 is a schematic diagram of the structure of the bed after moving according to the embodiment of the present application;

Fig. 3 is a schematic structural diagram of a collimator according to an embodiment of the present application;

Fig. 4 is a schematic structural diagram of a base according to an embodiment of the present application;

Among them, 1 tube, 3 lesion position, 4 bed board, 5 detectors, 101 top cover, 102 drive motor, 103 first connector, 104 second connector, 105 first track bar, 106 second track bar, 107 Collimation blades, 108 gears, 201 lifting assembly, 202 lower frame, 203 upper frame, 204 second driving assembly.

Detailed ways

In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiment of the application will be clearly and completely described below in conjunction with the accompanying drawings in the embodiment of the application. Obviously, the described embodiment is only It is an embodiment of a part of the application, but not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by persons of ordinary skill in the art without creative efforts shall fall within the scope of protection of this application.

It should be noted that, in the case of no conflict, the embodiments in the present application and the features in the embodiments can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and embodiments.

In the process of CT scanning, the scanning table needs to carry the patient to move to the scanning center, so that the lesion area is inside the scanning fan angle, and the rays completely pass through the lesion to complete the scan. However, when scanning local organs such as the heart, lungs, and limbs, the lesion is located on one side of the patient, so the radiation on the other side does not play an imaging role, causing the patient to suffer from excess radiation (including the one shown in Figure 1 The rays in the effective area and the rays in the invalid area) endanger the health of the patient, and because the imaging position of the local organ after scanning is located at the edge of the detector, the image quality is poor.

In order to solve the above technical problems, as shown in Figure 2, an embodiment of the present application provides a CT scanning device, the CT scanning device includes:

CT main body, including tube 1, detector 5 and collimator;

The collimator includes two collimating blades 107, and the two collimating blades 107 can move along the X-axis direction, so that the distance between the two collimating blades 107 can be adjusted;

The bed board 4 can be driven to enter the CT main body along the Z axis, and the bed board 4 can be driven to move along the X axis direction, so that the projection of the lesion position 3 on the detector 5 is located in the middle of the detector 5;

The Z axis is the pushing direction of the bed board 4, and the X axis is the horizontal direction and is perpendicular to the Z axis.

In this embodiment, the CT scanning device is mainly composed of a CT main body and a bed board 4, wherein the CT main body is mainly composed of a tube 1, a detector 5 and a collimator. The collimator and detector 5 are integrated on the rotating part of the scanning frame to follow the rotation, and the bed board 4 carries the patient to move in the Z-axis direction. The scanning process can be simply described as, the tube 1 emits X-rays, the collimator controls the fan angle of the rays, the rays pass through the patient lying on the bed board 4, and the detector 5 receives the rays to complete the scanning process. The patient generally lies in the middle of the bed board 4, and the tube 1 and the detector 5 are located directly above and directly below the patient respectively. Therefore, in order to obtain a better quality image of the lesion located in the non-middle position of the patient after scanning, it is necessary to scan the X Moving the patient in the axial direction moves the lesion position 3 to a position opposite to the middle of the detector 5, that is, the projection of the lesion position 3 on the detector 5 is located in the middle of the detector 5 (as shown in Fig. 1 and Fig. 2 ). In order to facilitate the movement of the patient, in addition to moving in the Z-axis direction for conventional scanning, the bed board 4 in this embodiment can also move in the X-axis direction according to the lesion position 3, so that the lesion position 3 can be moved to the same position as the detector 5 The middle part of the FOV is opposite, so that the lesion area can always be at the scanning center, and the image quality is better than that at the edge of the FOV, which can improve the image quality of the reconstruction mode.

On this basis, the two collimating blades 107 in the collimator in this application can also move along the X-axis direction, so that the distance between the two collimating blades 107 can be adjusted. When the two collimating blades 107 are close to each other, the scanning range formed by the rays passing through the two collimating blades 107 decreases; The scanning range increases. For the scanning of the local lesion area, the distance between the two collimating blades 107 can be adjusted according to the size of the lesion section, so that the formed scanning range is close to the edge of the lesion section, so that the non-lesion area does not touch the scanning rays, This reduces the patient's radiation exposure (as shown by the dotted line in Figure 2).

This embodiment achieves that the lesion can be imaged in the middle of the detector 5 after scanning by adjusting the position of the bed board 4 in the X-axis direction, and the distance between the two collimating blades 107 can be adjusted so that the rays pass through the collimator. The scanning range of the straight blade 107 can match the lesion cross-section, thereby improving the image quality of the reconstruction mode, and completing the scanning of the patient's local lesion area with a small scanning dose, reducing the technical effect of the patient's exposure to radiation , so as to solve the problem that when the scanning device in the related art scans the local organs, the patient will bear redundant radiation, and because the imaging position of the local organs after scanning is located at the edge of the detector 5, the problem of poor image quality .

For the convenience of controlling the linear movement of the collimating blades 107 in the X-axis direction, as shown in Figure 3, the collimator in this embodiment also includes a top cover 101 and a first driving assembly arranged on the top cover 101, the collimator The blades 107 are arranged on the top cover 101 , and the first driving assembly is connected with the collimating blades 107 for driving the collimating blades 107 to move along the X-axis direction.

In this embodiment, the first driving assembly is used to drive the two collimating blades 107 to move linearly in the X-axis direction, so the first driving assembly can adopt any structure capable of outputting linear motion. Linear motors, cylinders, hydraulic cylinders, etc. It can be understood that the two collimating blades 107 can be driven by the same first driving assembly, or can be driven by a first driving assembly respectively. In this embodiment, the collimation blade 107 is a tungsten sheet.

In order to improve the stability of the straight-line movement of the collimation blades 107 , in this embodiment, a slide rail is provided on the top cover 101 along the X-axis direction, and the collimation blades 107 are slidably arranged in the slide rails. Further, the slide rail includes a first track bar 105 and a second track bar 106 , slide grooves are opened on opposite sides of the first track bar 105 and the second track bar 106 , and two sides of the alignment blade 107 are slidably connected with the slide grooves.

In order to control the synchronous movement of the two collimating blades 107, the first driving assembly in this embodiment includes a driving motor 102, a first connecting member 103 and a second connecting member 104; the output end of the driving motor 102 is provided with a gear 108; One connecting piece 103 is connected with one of the collimating blades 107, the second connecting piece 104 is connected with the other collimating blade 107, the first connecting piece 103 is provided with a rack meshed with the first side of the gear 108, the second connecting piece The member 104 is provided with a rack meshing with the second side of the gear 108 .

In this embodiment, the driving motor 102 is installed on one side of the top cover 101, and the driving motor 102 can drive the gear 108 to rotate at a fixed axis, so as to drive the first connecting part 103 and the second connecting part 104 on both sides of the gear 108 to be meshed. move or move away from each other, and then drive the two collimating blades 107 to move relative to each other or move away from each other. Through the cooperation of the gear 108 and the rack, the movement of the two collimating blades 107 is precise and synchronous, so that the center of the scanning range and the center of the detector 5 can always be consistent, and high-quality images can be obtained after the lesion position 3 moves to the center. At the same time, the radiation dose to the patient is reduced to the greatest extent.

Further, since the bed board 4 can move to the scanning center along the X-axis direction, the collimator can drive the X-axis direction to mirror and move the collimator through a single drive motor 102, simplifying the structure and decoupling the cooperative movement of the collimator and the bed board 4 , to simplify the control process.

In order to realize the movement of the bed board 4 , as shown in FIG. 4 , this embodiment also includes a base on which a second driving assembly 204 is arranged to drive the bed board 4 to move along the X-axis direction. The second driving assembly 204 is also used as a structure for driving the bed board 4 to move linearly along the X-axis direction, and various structures with linear movement output functions in the related art can be used, such as screw, connecting rod, cylinder, linear motor, etc.

Since the bed board 4 needs to have the functions of linearly moving along the Z axis, lifting along the vertical direction (Y axis), and linearly moving along the X axis during use, the base in this embodiment includes a lifting assembly 201 and a lower frame 202 , the lower end of the bed board 4 is provided with an upper frame 203;

The lower frame 202 is arranged on the output end of the lifting assembly 201, the second drive assembly 204 is arranged in the lower frame 202, the upper frame 203 is arranged on the lower frame 202 and can move along the X-axis direction, the second drive assembly 204 and the upper frame 203 connect. The second driving assembly 204 includes a linear motor, and the linear motor is connected to the upper frame 203 in transmission.

In this embodiment, the lifting assembly 201 can be used to control the vertical lifting of the bed board 4 , and the lifting assembly 201 can adopt a scissor-type lifting structure. The lower frame 202 is provided with a slide rail for the linear movement of the upper frame 203. The direction of the slide rail is the X-axis direction, so the upper frame 203 with the bed board 4 can move linearly along the X-axis on the lower frame 202, that is, the bed board 4 It can move linearly along the X axis. The lifting assembly 201, the lower frame 202, the upper frame 203 and the bed board 4 can be installed on the Z-axis translation structure as a whole, and the Z-axis translation structure can adopt the structure of CT equipment in the related art, which will not be repeated in this embodiment.

According to another aspect of the present application, there is provided a scanning method for reducing CT radiation in an adaptive scanning area, using the above-mentioned CT scanning device, and the following steps:

Perform one or more scans and obtain scan results;

Calculate ROI section parameters and positions based on the scan results, that is, determine the lesion position 3 and the parameters of each section of the lesion in the Z-axis direction according to the scan results;

Based on the section parameters and positions of the ROI, determine the movement stroke of the bed board 4 in the X-axis direction, that is, determine the movement stroke of the bed board 4 in the X-axis direction when scanning each lesion section according to the various section parameters and positions of the lesions. During the process, when the bed board 4 moves according to the movement stroke, each section of the lesion can be projected to the middle of the detector 5;

Based on the ROI section parameters and position, determine whether the small FOV scanning mode is satisfied, that is, according to whether the obtained lesion section parameters and positions are within the scanning range of the two collimating blades 107 when the distance is the largest; if so, then according to the lesion section parameters, The distance between the two collimation blades 107 is adjusted so that the scanning boundary fits the section of the lesion and the scanning is performed. For example, when the lesion section parameter is smaller than the scanning range formed by the first two collimating blades 107, the two collimating blades 107 can be moved closer to each other through the first driving assembly until the scanning range is close to the lesion section.

The method of calculating the spacing of the collimating blades 107 based on the lesion section parameters is as follows: after obtaining the lesion section parameters, the emission point of the bulb 1 is used as the upper vertex of the triangle, and the two sides of the lesion section are used as the two side vertices of the triangle to form a triangle. The line connecting the two collimating blades 107 in the X-axis direction has an intersection point with each of the two sides of the triangle, and the distance between the two intersection points is equal to the distance between the collimating blades 107 after moving along the X-axis direction.

This embodiment achieves that the lesion can be imaged in the middle of the detector 5 after scanning by adjusting the position of the bed board 4 in the X-axis direction, and the distance between the two collimating blades 107 can be adjusted so that the rays pass through the collimator. The scanning range of the straight blade 107 can match the lesion cross-section, thereby improving the image quality of the reconstruction mode, and completing the scanning of the patient's local lesion area with a small scanning dose, reducing the technical effect of the patient's exposure to radiation , so as to solve the problem that when the scanning device in the related art scans the local organs, the patient will bear redundant radiation, and because the imaging position of the local organs after scanning is located at the edge of the detector 5, the problem of poor image quality .

When the acquired lesion cross-sectional parameters and positions are not within the scanning range of the two collimating blades 107 at the maximum distance, the size of the surface lesion is larger than the maximum scanning range of the CT main body, and multiple scans are required, so the collimator can be adjusted on the Z axis direction and perform the normal scanning process.

The above descriptions are only preferred embodiments of the present application, and are not intended to limit the present application. For those skilled in the art, there may be various modifications and changes in the present application. Within the spirit and principles of this application, any modifications, equivalent replacements, improvements, etc., shall be included within the protection scope of this application.

Claims (10)

1. A CT scanning device, characterized in that, comprising: CT main body, including tube, detector and collimator; The collimator includes two collimating blades, and the two collimating blades can move along the X-axis direction, so that the distance between the two collimating blades can be adjusted; The bed board can be driven to enter the CT main body along the Z axis, and the bed board can be driven to move along the X axis direction, so that the projection of the lesion position on the detector is located in the middle of the detector; The Z-axis is the pushing direction of the bed board, and the X-axis is horizontal and perpendicular to the Z-axis. 2. The CT scanning device according to claim 1, wherein the collimator further comprises a top cover and a first driving assembly arranged on the top cover, and the collimating blades are arranged on the top cover On the cover, the first driving assembly is connected to the collimating blades and used to drive the collimating blades to move along the X-axis direction. 3 . The CT scanning device according to claim 2 , wherein a sliding rail is provided on the top cover along the X-axis direction, and the collimation blade is slidably arranged in the sliding rail. 4 . 4. The CT scanning device according to claim 3, wherein the slide rail comprises a first track bar and a second track bar, the opposite sides of the first track bar and the second track bar are provided with a chute, and the two sides of the collimation blade are slidably connected with the chute. 5. The CT scanning device according to any one of claims 2 to 4, wherein the first drive assembly includes a drive motor, a first connecting member and a second connecting member; The output end of the drive motor is provided with a gear; The first connecting piece is connected to one of the collimating blades, the second connecting piece is connected to the other of the collimating blades, and the first connecting piece is provided with a gear that meshes with the first side of the gear. The second connecting member is provided with a rack meshing with the second side of the gear. 6. The CT scanning device according to claim 1, further comprising a base, the base is provided with a second drive assembly, and the second drive assembly is used to drive the bed plate along the X-axis direction move. 7. The CT scanning device according to claim 6, wherein the base comprises a lifting assembly and a lower frame, and the lower end of the bed board is provided with an upper frame; The lower frame is arranged at the output end of the lifting assembly, the second driving assembly is arranged in the lower frame, the upper frame is arranged on the lower frame and can move along the X-axis direction, and the second driving assembly is arranged in the lower frame. The second driving assembly is connected with the upper frame. 8 . The CT scanning device according to claim 7 , wherein the second driving assembly comprises a linear motor, and the linear motor is in transmission connection with the upper frame. 9. A scanning method for reducing CT radiation in an adaptive scanning area, characterized in that, using the CT scanning device according to any one of claims 1 to 8, and following steps: Perform one or more scans and obtain scan results; Calculate ROI section parameters and positions based on the scanning results; Based on the ROI section parameter and position, determine the movement stroke of the bed board in the X-axis direction; Based on the moving stroke, controlling the movement of the bed board so that the projection of the lesion position on the detector is located in the middle of the detector; Based on the ROI section parameters and position, it is determined whether the small FOV scanning mode is satisfied, and if so, the distance between the two collimation blades is adjusted so that the scanning boundary fits the lesion section and the scanning is performed. 10. The scanning method for reducing CT radiation by adaptive scanning area according to claim 9, characterized in that, based on the ROI section parameters and position, determine whether the small FOV scanning mode is satisfied, if not, Adjust the collimating blades to move in the Z-axis direction and perform a scan.

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