Novel CBCT system based on novel line scanning bulb tube

Abstract

The invention provides a novel CBCT system based on a novel line scanning bulb tube, and belongs to the technical field of X-ray medical image.The novel CBCT system comprises a sampling system and a control system.The sampling system comprises a bulb tube with a light source focus capable of conducting linear track scanning, an energy integration or photon counting detector and a movement rack system; the scanning type anode of the bulb tube can be composed of discrete array light sources and can also be composed of rotary wing anodes, and light source focuses conduct controllable, rapid and repeated scanning or movement in a motion system. Imaging is carried out through controllable light source focus linear track scanning, an imaging method similar to tomosynthesis is achieved at the position of a single bulb tube, and CBCT imaging is achieved under the condition of limited angle sampling through a rotary light source-detector rack combination.

Description

Technical Field

[0001] This invention belongs to the field of medical energy spectrum technology, and in particular relates to a novel CBCT system based on a novel line scanning X-ray tube. Background Technology

[0002] The principle of CT (computed tomography) scanning is that when X-rays penetrate the human body, different substances have different attenuation intensities. By scanning the human body with X-rays, attenuation information of the ray path can be obtained. Then, by analyzing and reconstructing the attenuation information, the material distribution information of the scan tomographic section can be obtained.

[0003] CBCT is an essential navigation imaging tool for image-guided or robot-assisted spinal surgery. Usually, the screw trajectory is planned directly by the surgeon on the intraoperative CBCT or planned on the preoperative CT image and then registered to the intraoperative CBCT.

[0004] In orthopedic or interventional surgeries, real-time observation, positioning, and navigation of patients or interventional devices rely heavily on high-performance imaging equipment. The proposed static CT imaging technology based on line-scan X-ray sources can provide instantaneous real-time three-dimensional images. Currently, domestic and international CBCT imaging equipment and modes are limited to single X-ray source C-arms or O-arms.

[0005] Currently, cone-beam computed tomography (CBCT) systems such as C-arms and O-arms require multi-angle scanning around the patient (typically requiring more than 200 2D image acquisitions) to acquire 3D images, and then use reconstruction algorithms to obtain CBCT imaging results. Although it is intraoperative CBCT, the scanning and imaging processes still take several minutes, making it difficult to achieve true real-time 3D imaging. In scenarios where patient movement is possible, such as during breathing or other involuntary movements, this introduces uncertainty into high-precision robot-assisted surgery.

[0006] Linear distributed light source CT is a novel tomographic imaging method that has developed rapidly in recent years. It achieves scanning by using multiple statically placed line light sources and X-ray tubes, avoiding the rotation of the CT gantry to improve the imaging speed of CT scans and simplifying CT system design. Currently, the line light sources used in this static CT scanning include carbon nanotube cold cathode distributed X-ray sources and small array X-ray tubes (multiple light sources arranged independently). Due to the size and manufacturing limitations of the X-ray tubes, the number of X-ray tubes arranged in a straight line is limited. Summary of the Invention

[0007] To address the shortcomings of existing technologies, this invention proposes a novel CBCT system based on a novel line-scan X-ray tube. Through the rotating wing anode tube, its focal point can move rapidly and repeatedly within a line segment, enabling CBCT scanning imaging to be obtained under limited angle sampling conditions.

[0008] To solve the above problems, the present invention adopts the following technical solution: A novel CBCT system based on a novel line-scanning X-ray tube includes a sampling system and a control system. The sampling system includes an X-ray tube, a detector, and a motion gantry system. The X-ray tube includes a scanning anode and a movable light source focal spot. The motion gantry system includes a C-arm and a rocker arm. The X-ray tube and the detector are respectively fixed at both ends of the C-arm. The object to be measured is placed between the X-ray tube and the detector. The light source focal spot performs controllable, rapid, and repetitive scanning or movement within the motion gantry system.

[0009] Furthermore, the X-ray tube can be a discrete array light source X-ray tube or a rotating wing anode X-ray tube, and the detector can be an energy integration or photon counting detector.

[0010] Furthermore, a fixed shaft is provided between the ball tube and the C-shaped arm, and the ball tube can rotate around the fixed shaft of the C-shaped arm.

[0011] Furthermore, the array point light source tube includes discrete linearly arranged light source focal points, which are arranged along a straight line.

[0012] Furthermore, the rotating blade anode tube includes continuously rotatingly distributed light source focal points, which are spirally arranged along the tube.

[0013] Furthermore, the control system includes a host computer and a display, the host computer being movably connected to the C-arm.

[0014] The beneficial effects of the present invention are as follows: the X-ray tube used in the present invention is no longer the single-focus form of the traditional rotating anode, but a new type of rotating blade anode X-ray tube, whose focus can move rapidly and repeatedly within a line segment (millisecond-level speed). In addition, by using this rotating wing X-ray tube or array point light source X-ray tube, a three-dimensional reconstruction image of tomographic fusion scanning can be obtained at a single projection angle. When the X-ray tube-detector system rotates, CBCT scanning imaging can be obtained under limited angle sampling conditions.

[0015] Furthermore, due to its extremely high scanning efficiency, data acquisition can be completed in a shorter time, reducing unnecessary exposure time. Additionally, the optimized sampling trajectory may mean that fewer X-ray photons are required to achieve the same image quality. Attached Figure Description

[0016] To more clearly illustrate the specific embodiments of the present invention, the accompanying drawings used in the description of the specific embodiments will be briefly introduced below.

[0017] Figure 1 These are schematic diagrams of three different light source-detector structures; Figure 2 This is a schematic diagram of the novel line-scan X-ray tube CBCT system of the present invention; Figure 3 This is a schematic diagram of a static scan of the present invention; Figure 4 This is a schematic diagram of the geometric structure of the novel line light source of the present invention; Figure 5 This is a schematic diagram of a polygonal scanning method for a novel X-ray tube CBCT scanner according to the present invention; Figure 6 The tomographic fusion scan three-dimensional reconstruction image generated by this invention; Figure 7 The polygonal scan trajectory reconstruction image generated by this invention. Detailed Implementation

[0018] To enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0019] like Figure 1 As shown, Figure 1 (a) is a schematic diagram of a traditional CBCT light source-detector structure; Figure 1 (b) is a schematic diagram of the array line light source-detector structure; Figure 1 (c) is a schematic diagram of the structure of a new type of line source-detector CBCT. Currently, the line sources used in this type of static CT scanning include carbon nanotube cold cathode distributed X-ray sources, small array X-ray tubes (multiple light sources arranged independently), etc. Due to the limitations of X-ray tube volume and processing, the number of X-ray tubes arranged in a straight line is limited.

[0020] like Figure 2 As shown, this invention proposes a novel CBCT system based on a novel line-scanning X-ray tube, including a sampling system and a control system. The sampling system includes an X-ray tube, a detector, and a motion gantry system. The X-ray tube includes a scanning anode and a movable light source focal spot. The motion gantry system includes a C-arm and a rocker arm. The X-ray tube and the detector are respectively fixed at both ends of the C-arm. A fixed axis is provided between the X-ray tube and the C-arm, and the X-ray tube can rotate around the fixed axis of the C-arm. The detector is an energy integration or photon counting detector. The object to be measured is placed between the X-ray tube and the detector. The light source focal spot performs controllable, rapid, and repetitive scanning or movement within the motion gantry system. The control system includes a host and a display. The host is movably connected to the C-arm.

[0021] This system mainly has four different scanning methods. The following is a further introduction to the scanning methods of the system with reference to specific embodiments.

[0022] The linear scan reconstruction formula in this system is as follows:

[0023]

[0024] The above formula is for the reconstruction data of linear trajectory scanning. That is, when the scanning trajectory is a straight line or a polygon, the above formula can be used to reconstruct the image. In Example 2, Tomosynthesis reconstruction can be performed on a single linear trajectory. In Example 4, tomographic reconstruction of an image under a polygonal scanning trajectory can be performed.

[0025] like Figure 2 (a) Figure 3 (a) Figure 5 As shown in (a), the X-ray tube is a rotating blade anode X-ray tube, which includes continuously rotatingly distributed light source focal points, which are spirally arranged along the X-ray tube.

[0026] like Figure 2 (b) Figure 3 (b) Figure 5 As shown in (b), the X-ray tube adopts a discrete array light source X-ray tube, which includes discrete linearly arranged light source focal points, and the light source focal points are arranged along a straight line. Example 1

[0027] In this embodiment, as Figure 2 As shown, the rotating wing anode tube or array light source tube and flat panel detector are fixed on the C-arm. The entire C-arm rotates around the object being measured under the clamping of the rocker arm, thereby realizing a circular scanning trajectory and performing traditional CT axial scanning. The scanning time of traditional scanning mainly depends on the rotation speed of the tube-detector structure. Example 2

[0028] In this embodiment, as Figure 3 As shown, the entire C-arm remains stationary, i.e., a static scan. When this scanning method is implemented, as follows: Figure 4 As shown, the helical target surface of the X-ray tube rotates around its central axis, and the electron beam bombardment position continuously moves with the rotation of the target surface, thus achieving continuous line scanning. The scanning rays scan the object under test from different angles. The scanning time of this method mainly depends on the sampling frequency of the detector. Using this data, tomographic fusion scanning three-dimensional reconstruction images (Tomosynthesis) can be realized, and the imaging is as follows: Figure 6 As shown, the images are the images reconstructed using the above formula after frontal and lateral linear scanning, respectively. They are tomographic fusion images reconstructed using only data collected from a single straight line scanning trajectory. Example 3

[0029] In this embodiment, the rotating wing anode tube or array light source tube is in a non-stationary state, and other technical features are the same as in Embodiment 1.

[0030] Based on the first scanning method, by combining the rotation of the target surface of the linear X-ray tube (or the linear movement of the focal position of the discrete linear X-ray tube), the spiral trajectory of the light source can be realized, thereby achieving spiral scanning. Example 4

[0031] In this embodiment, as Figure 5 As shown, when the X-ray tube is rotated onto the axial scanning surface, polygon scanning can be achieved. All the data required for reconstruction can be obtained simply by rotating the C-arm to a few fixed angles. Throughout the scanning process, the light source trajectory is polygonal, and the imaging is as follows: Figure 7 As shown, in traditional CT scans, rotating the light source and detector structure by 180°+2α is sufficient to obtain complete data for reconstructing the central tomographic image, where α is the beam fan angle. In this linear CBCT, since the light source itself can move within a fixed C-arm angle to achieve imaging within a certain angular range, the C-arm only needs to be moved to a few fixed positions. At these positions, data from adjacent angles is supplemented by moving the focal point. Therefore, to obtain complete data, it is only necessary to ensure that the angle of the circular trajectory light source equivalent to the moving focal point satisfies 180°+2α. In this scanning method, the factors affecting scanning time mainly include the light source-detector rotation speed and the detector sampling frequency. Since sampling only needs to be performed from a few fixed angles, the required rotation speed of the scanning structure is reduced, thereby shortening the scanning time.

[0032] The present invention has been described in detail above through embodiments, but the content is only a preferred embodiment of the present invention and should not be considered as limiting the scope of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the patent coverage of the present invention.

Claims

1. A novel CBCT system based on a novel line-scan X-ray tube, characterized in that: The system includes a sampling system and a control system. The sampling system includes an X-ray tube, a detector, and a motion frame system. The X-ray tube includes a scanning anode and a movable light source focal point. The motion frame system includes a C-arm and a rocker arm. The X-ray tube and the detector are respectively fixed at both ends of the C-arm. The object to be measured is placed between the X-ray tube and the detector. The light source focal point performs controllable, rapid, and repeatable scanning or movement within the motion frame system.

2. The novel CBCT system based on a novel line-scan X-ray tube according to claim 1, characterized in that: The X-ray tube can be a discrete array light source X-ray tube or a rotating wing anode X-ray tube, and the detector can be an energy integration or photon counting detector.

3. A novel CBCT system based on a novel line-scan X-ray tube according to claim 2, characterized in that: A fixed shaft is provided between the ball tube and the C-shaped arm, and the ball tube can rotate about it on the fixed shaft of the C-shaped arm.

4. A novel CBCT system based on a novel line-scan X-ray tube according to claim 2, characterized in that: The array point light source tube includes discrete linearly arranged light source focal points, which are arranged along a straight line.

5. A novel CBCT system based on a novel line-scan X-ray tube according to claim 2, characterized in that: The rotating blade anode tube includes continuously rotatingly distributed light source focal points, which are spirally arranged along the tube.

6. A novel CBCT system based on a novel line-scan X-ray tube according to claim 1, characterized in that: The control system includes a host and a display, the host being movably connected to the C-arm.

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