CT imaging system

Abstract

The present invention relates to a CT imaging system, comprising a radiation source, a carrier stage for supporting a sample to be scanned, and a detector which are arranged in sequence. A phantom is fixedly installed on the carrier stage, and the projections of said sample and the phantom fall within the receiving range of the detector. According to the present invention, the phantom and the carrier stage are fixed together, so that a single CT scan can complete scanning of the phantom to calculate corresponding geometric parameters, while simultaneously completing scanning of said sample. That is, each CT scan can instantly calculate the geometric parameters under the current scan, thereby accommodating different CT scanning scenarios under the condition that the detector, the radiation source, and the carrier stage are mutually independent and movable, without the need for additional scans. When powered by a battery, this design can reduce extra energy consumption of the battery.

Description

A CT imaging system Technical Field

[0001] This invention relates to the field of CT imaging technology, and more particularly to a CT imaging system. Background Technology

[0002] CT (Computed Tomography), also known as electronic computed tomography, taking sector-beam CT as an example, uses a precisely collimated beam of light and a highly sensitive detector to scan a specific part of the human body one section after another. It features fast scanning time and clear images and can be used to examine a variety of diseases.

[0003] Each CT scan requires acquiring the corresponding geometric parameters, such as the distance from the radiation source to the detector (SAD), the distance from the radiation source to the scanned object (SOD), the detector tilt angle (rot), the mapping position of the radiation source focus on the detector plane (U0, V0), and the detector dimensions. When the positions of all components in a CT imaging system remain stationary, a pre-designed phantom can be scanned first. Using the phantom's characteristics, the geometric parameters required for CT reconstruction can be calculated. Then, when reconstructing a real sample, these previously calculated geometric parameters can be used.

[0004] However, to increase the flexibility of CT scans, in many cases the detector, radiation source, and platform are not fixed by mechanical hardware connections, but are independent, movable entities. Therefore, the geometric parameters cannot remain constant. Furthermore, performing an additional scan on a specific phantom before each scan would reduce work efficiency and, in the case of battery power, increase additional battery energy consumption. Summary of the Invention

[0005] The present invention provides a CT imaging system to solve the above-mentioned technical problems.

[0006] To solve the above-mentioned technical problems, the present invention provides a CT imaging system, including a radiation source, a support stage for carrying a sample to be scanned, and a detector arranged in sequence. A phantom is fixedly installed on the support stage, and the projections of the sample to be scanned and the phantom are located within the receiving range of the detector.

[0007] Preferably, the mold is embedded inside the support platform.

[0008] Preferably, the mold body is fixed to the outer surface or extension of the support platform by a connecting structure.

[0009] Preferably, the support platform rotates about a longitudinal central axis, and the image of the phantom is located at the upper or lower edge of the detector.

[0010] Preferably, the mold body uses at least two metal beads, the positions of the metal beads are offset from the central axis, and the metal beads have a height difference in the direction along the central axis.

[0011] Preferably, the height difference between the metal beads is 1cm ± 0.2cm.

[0012] Preferably, the metal beads are made of steel or tungsten.

[0013] Preferably, the number of metal beads is 2 to 10.

[0014] Preferably, the source emits X-rays or gamma rays.

[0015] Preferably, the support platform is made of plastic or carbon fiber material.

[0016] Compared with the prior art, the CT imaging system provided by the present invention has the following advantages:

[0017] 1. This invention fixes the phantom and the support stage together, so that the phantom can be scanned in one CT scan, thereby calculating the corresponding geometric parameters. At the same time, the sample to be scanned is also scanned. That is, the geometric parameters under the current scan can be calculated in real time for each CT scan, so as to meet the requirements of different CT scan conditions when the detector, radiation source and support stage are independent and movable, without the need to increase the number of scans. When powered by battery, it can reduce the extra energy consumption of battery.

[0018] 2. This invention only requires fixing and combining the support platform and the phantom body, without needing to make many improvements to the existing imaging system and algorithm. It has a simple structure and low cost. Attached Figure Description

[0019] Figure 1 is a schematic diagram of the structure of a CT imaging system according to a specific embodiment of the present invention;

[0020] Figure 2a is a schematic diagram of the results of CT scanning and reconstruction of line-to-card using a conventional CT imaging system;

[0021] Figure 2b is a schematic diagram of the results of CT scanning and reconstruction of line-to-card using the CT imaging system in a specific embodiment of the present invention.

[0022] In the diagram: 10-source, 11-beam, 20-stage, 21-sample to be scanned, 30-detector, 40-phantom. Detailed Implementation

[0023] To illustrate the technical solutions of the invention in more detail, specific embodiments are listed below to demonstrate the technical effects; it should be emphasized that these embodiments are used to illustrate the invention and not to limit the scope of the invention.

[0024] The CT imaging system provided by this invention, as shown in Figure 1, includes a radiation source 10, a support stage 20 for carrying a sample 21 to be scanned, and a detector 30 arranged sequentially. A phantom 40 is fixedly mounted on the support stage 20. The projections of the sample 21 to be scanned and the phantom 40 are located within the receiving range of the detector 30. By using the beam 11 emitted by the radiation source 10 to simultaneously acquire the projections of the sample 21 to be scanned and the phantom 40 on the detector 30, the scanning of the phantom 40 can be completed in a single CT scan, thereby calculating the corresponding geometric parameters. Simultaneously, the scanning of the sample 21 to be scanned is completed. This system can meet the requirements of different CT scanning situations when the detector, radiation source, and support stage are independent and movable, without requiring additional scans. When powered by a battery, it can reduce the additional energy consumption of the battery.

[0025] It should be noted that the CT imaging system in this application can be used for CT scanning methods such as fan-beam CT scanning and cone-beam CT scanning, and this application does not limit it.

[0026] In some embodiments, the mold 40 can be embedded inside the support platform 20; in other embodiments, the mold 40 can be attached to the outer surface of the support platform 20; in still other embodiments, the mold 40 can also be fixed to the outer extension of the support platform 20 by a connecting structure, for example, by a fixing member extending from the support platform 20. That is, it is only necessary to ensure that the relative position of the mold 40 and the support platform 20 remains fixed; the positional relationship between the two and the installation method are not limited.

[0027] In some embodiments, the stage 20 can rotate about a longitudinal central axis, and the image of the phantom 40 is located at the upper or lower edge of the detector 30 to ensure that the projection of the phantom 40 does not affect the accuracy of the sample 21 to be scanned during CT scanning. Of course, if the stage 20 rotates about a transverse central axis, the image of the phantom 40 will be located at the left or right edge of the detector 30, which does not affect the CT scan of the sample 21 to be scanned.

[0028] In some embodiments, the phantom 40 may employ at least two metal beads, the positions of which are offset from the central axis. The metal beads have a height difference along the central axis. In some embodiments, the height difference between the metal beads is 1cm ± 0.2cm, which can accurately characterize the geometric parameters under the current scan without losing too much height field of view. Taking the detector 30 with a height of 43cm and a magnification of 1.5x as an example, the loss of height field of view is less than 4%, which does not affect the normal CT scan function.

[0029] In some embodiments, the metal beads may be made of steel or tungsten and have strong radiation absorption capabilities.

[0030] In some embodiments, the number of metal beads can be 2 to 10, which can obtain accurate geometric parameters without increasing costs excessively. In some embodiments, multiple metal beads can be integrated into a mold. For example, four metal balls can be arranged in a direction parallel to (not overlapping) the central axis and fixed into a cylindrical mold, which is then mounted on the support body 20.

[0031] In some embodiments, the radiation source 10 can emit X-rays or gamma rays to achieve rapid and clear scanning.

[0032] In some embodiments, the support platform 20 may be made of non-metallic materials such as plastic or carbon fiber, without affecting the detector 30's recognition of the phantom 40.

[0033] This application uses a conventional CT imaging system and the CT imaging system proposed in this invention to perform CT scanning and reconstruction using line-pair cards, which are most sensitive to geometric relationships. Specifically, the conventional CT imaging system performs two CT scans, and the positions of the radiation source, stage, and detector cannot be moved; using the CT imaging system proposed in this invention, the radiation source, stage, and detector can move independently, and only one CT scan is performed. The final reconstruction results are shown in Figures 2a and 2b. As can be seen from the figures, the reconstruction effects of the two systems are basically the same.

[0034] In summary, the CT imaging system provided by this invention includes a radiation source 10, a support stage 20 for carrying the sample 21 to be scanned, and a detector 30 arranged sequentially. A phantom 40 is fixedly mounted on the support stage 20, and the projections of the sample 21 to be scanned and the phantom 40 are located within the receiving range of the detector 30. By using the beam 11 emitted by the radiation source 10 to simultaneously acquire the projections of the sample 21 to be scanned and the phantom 40 on the detector 30, the scanning of the phantom 40 can be completed in a single CT scan, thereby calculating the corresponding geometric parameters. At the same time, the scanning of the sample 21 to be scanned is completed. This system can meet the requirements of different CT scanning situations when the detector, radiation source, and support stage are independent and movable, without the need for additional scans. When powered by a battery, it can reduce the additional energy consumption of the battery.

[0035] Obviously, those skilled in the art can make various modifications and variations to the invention without departing from the spirit and scope of the invention. Therefore, if these modifications and variations fall within the scope of the claims of the invention and their equivalents, the invention is also intended to include these modifications and variations.

Claims

1. A CT imaging system, characterized by, It includes a radiation source, a support stage for carrying the sample to be scanned, and a detector arranged in sequence. A phantom is fixedly installed on the support stage, and the projections of the sample to be scanned and the phantom are located within the receiving range of the detector.

2. The CT imaging system as described in claim 1, characterized in that, The mold is embedded inside the support platform.

3. The CT imaging system as described in claim 1, characterized in that, The mold body is fixed to the outer surface or extension of the support platform by a connecting structure.

4. The CT imaging system as described in claim 1, characterized in that, The support platform rotates around the longitudinal central axis, and the image of the phantom is located at the upper or lower edge of the detector.

5. The CT imaging system as described in claim 4, characterized in that, The mold body uses at least two metal beads, the positions of which are offset from the central axis, and the metal beads have a height difference along the central axis.

6. The CT imaging system as described in claim 5, characterized in that, The height difference between the metal beads is 1cm ± 0.2cm.

7. The CT imaging system as described in claim 5, characterized in that, The metal beads are made of steel or tungsten.

8. The CT imaging system as described in claim 5, characterized in that, The number of metal beads is 2 to 10.

9. The CT imaging system as described in claim 1, characterized in that, The radiation source emits X-rays or gamma rays.

10. The CT imaging system as claimed in claim 1, characterized in that, The support platform is made of plastic or carbon fiber material.

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