PET long axial visual field quantitative correction method and device

Abstract

The invention relates to a PET long axial visual field quantitative correction method and device. The method comprises the steps that the center of the PET long axial visual field quantitative correction device fixed to a bed board is roughly adjusted to coincide with the center of ISO; determining a deviation value between the center of the correction device and the center of the ISO by using the PET image; performing fine adjustment on the correction device according to the deviation value to enable the center of the correction device to coincide with the center of the ISO; attenuation correction is completed based on CT scanning; pET quantitative correction scanning is carried out, and PET long axial visual field quantitative correction is completed. The method has the beneficial effects that the image quality and the diagnosis accuracy are improved, and meanwhile, the problem that the quantitative correction accuracy cannot be improved through attenuation correction by virtue of nuclear medical imaging equipment such as PET (Polyethylene Terephthalate) with long axial view field and the like is solved.

Description

Technical Field

[0001] The present invention relates to the field of medical imaging technology, and in particular to a PET long-axial field of view quantitative correction method and device. Background Art

[0002] In the field of medical equipment, especially in the field of nuclear medicine and imaging technology, positron emission tomography (PET) and positron emission and computed tomography (PET / CT) are important imaging technologies and diagnostic tools in modern medicine. These devices generate images by detecting positrons emitted by radioactive tracers in the body, obtain image information inside the human body, and help doctors diagnose and treat diseases. During the PET imaging process, the original PET image data needs to be corrected based on regular quantitative correction data to ensure the accuracy and reliability of the image. This quantitative correction depends on a certain hardware phantom and the compatibility of the phantom with the PET system or PET / CT system.

[0003] In the related art, quantitative calibration is to infuse a certain dose of 18F-FDG into the phantom, hang the phantom at the front end of the bed, ensure that there is only air around the phantom without any high-density objects, and then perform a PET scan. The phantom can quantitatively analyze the imaging field of the PET device and perform calibration based on the analysis results. In addition, in order to ensure the accuracy and stability of the calibration, the calibration device needs to be regularly tested and calibrated.

[0004] However, the relevant technology still has some problems and limitations in this field. First, no attenuation correction is performed before quantitative correction, resulting in low accuracy of the quantitative correction results. Secondly, in the application of PET long axial field of view, a phantom covering the entire axial field of view must be configured. If other imaging devices such as CT are used for attenuation correction, in general, in order to ensure the scanning length, the bed board will be closer to the imaging device for attenuation correction. If the phantom is hung at the front end of the bed board, it will inevitably lead to the inability to scan the entire long phantom and complete the attenuation correction. Therefore, in the actual application of the relevant technology, there are still some problems and challenges in terms of the accuracy of quantitative correction and the adaptability of the long axial field of view. Summary of the invention

[0005] Technical issues to be solved

[0006] In view of the above-mentioned shortcomings and deficiencies of the prior art, the present invention provides a method and device for quantitatively correcting the long axial field of view of PET, which solves the technical problems of low accuracy of quantitative correction of PET and insufficient adaptability of the long axial field of view.

[0007] Technical Solution

[0008] In order to achieve the above object, the main technical solutions adopted by the present invention include:

[0009] In a first aspect, the present invention provides a method for quantitatively correcting a PET long axial field of view, comprising:

[0010] Coarsely adjust the center of the PET long-axis field of view quantitative correction device fixed on the bed board to coincide with the ISO center;

[0011] Using PET images, determine the deviation between the center of the calibration device and the ISO center;

[0012] Fine-tune the correction device according to the deviation so that the center of the correction device coincides with the ISO center;

[0013] Attenuation correction is done based on CT scans;

[0014] Perform PET quantitative calibration scan and complete PET long axial field of view quantitative calibration.

[0015] Optionally, the center of the PET long axial field of view quantitative correction device fixed on the bed board is adjusted to coincide with the ISO center, including: adjusting the center of the PET long axial field of view quantitative correction device fixed on the bed board to coincide with the ISO center based on the reference laser line provided by the CT laser lamp.

[0016] Optionally, the attenuation correction includes: bed board attenuation correction, tissue attenuation correction and motion attenuation correction.

[0017] Optionally, attenuation correction is done based on the CT scan, including:

[0018] Obtain attenuation coefficient based on CT scan;

[0019] generating an attenuation map based on the screening coefficients;

[0020] Apply the attenuation map to the raw PET data to complete the attenuation correction.

[0021] In a second aspect, the present invention provides a PET long axial field of view quantitative correction device, comprising:

[0022] A cylindrical mold body, wherein a water outlet and a water inlet are arranged on a bottom surface of the cylindrical mold body;

[0023] A front support seat and a rear support seat are arranged on both sides of the cylindrical mold body and are used to fix the cylindrical mold body;

[0024] A front adjustment seat and a rear adjustment seat are connected to the front support seat and the rear support seat respectively;

[0025] The x-direction adjustment and locking knob, the y-direction adjustment knob and the z-direction adjustment and locking knob are arranged on the front adjustment seat and the rear adjustment seat, and are used to adjust the positions of the front adjustment seat and the rear adjustment seat.

[0026] Optionally, a longitudinal reference line and a transverse reference line are provided on the cylindrical mold body to provide references for the correction device in the vertical direction and the horizontal direction respectively.

[0027] Optionally, the correction device is fixed on the bed board by cooperating with the bed board locking knob through a bed board connector.

[0028] In a third aspect, the present invention provides a computer-readable storage medium having a computer program stored thereon, wherein when the program is executed, the method for quantitatively correcting the long axial field of view of PET as described in any one of the first aspects above is implemented.

[0029] In a fourth aspect, the present invention provides a storage device comprising a storage medium and a processor, wherein the storage medium stores a computer program, and when the program is executed by the processor, the method for quantitative correction of the long axial field of view of PET described in any one of the first aspects above is implemented.

[0030] Beneficial Effects

[0031] The beneficial effects of the present invention are as follows: a method and device for quantitative correction of the long axial field of view of PET of the present invention provides a phantom device that can be placed on a bed board to adjust the posture, adopts a new quantitative correction method, and adds an attenuation correction step to eliminate the influence of objective factors such as the environment and the bed board on the accuracy of quantitative correction, thereby improving the accuracy of system performance calibration, and further improving image quality and diagnostic accuracy. At the same time, it solves the problem that nuclear medicine imaging equipment such as PET with a long axial field of view cannot improve the accuracy of quantitative correction through attenuation correction. Since the present invention increases and optimizes the attenuation correction link, it can improve the accuracy of the original data, thereby improving the accuracy of the quantitative correction, making the results of the quantitative analysis more accurate, and ultimately improving the accuracy of the diagnosis. In addition, the quantitative correction phantom provided by the present invention is placed on the bed board instead of being hung on the head of the bed, so as to realize the quantitative correction of the long axial field of view of PET. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 A schematic diagram of a process for quantitative correction of a PET long axial field of view provided by an embodiment of the present invention;

[0033] Figure 2 A schematic structural diagram of a PET long axial field of view quantitative correction device provided by another embodiment of the present invention.

[0034] Description of Reference Numerals

[0035] 1: front support seat, 2: longitudinal reference line, 3: barrel-shaped mold body, 4: rear support seat, 5: drain outlet, 6: water inlet, 7: bed board locking knob, 8: bed board connector, 9: z-adjustment and locking knob, 10: rear adjustment seat, 11: x-adjustment and locking knob, 12: y-adjustment knob, 13: bed board, 14: transverse reference line, 15: front adjustment seat. DETAILED DESCRIPTION

[0036] In order to better explain the present invention and facilitate understanding, the present invention is described in detail below in conjunction with the accompanying drawings through specific embodiments. Although exemplary embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided in order to enable a clearer and more thorough understanding of the present invention and to be able to fully convey the scope of the present invention to those skilled in the art.

[0037] First, refer to Figure 1 This embodiment provides a PET long axial field of view quantitative correction method, including:

[0038] S1, roughly adjust the center of the PET long-axial field of view quantitative correction device fixed on the bed board to coincide with the ISO center.

[0039] S2, using the PET image to determine the deviation between the center of the correction device and the ISO center.

[0040] The ISO center usually refers to the geometric center or rotation center of the imaging system. This center point is the reference point when the system is scanning, ensuring the accuracy and consistency of image reconstruction. In PET imaging, the position of the ISO center has an important impact on image quality, resolution, and system performance. Therefore, when designing and calibrating equipment, special attention should be paid to the positioning and adjustment of this center.

[0041] S3, fine-tuning the correction device according to the deviation so that the center of the correction device coincides with the ISO center.

[0042] S4, attenuation correction is performed based on the CT scan.

[0043] S5, perform PET quantitative calibration scan to complete the PET long axial field of view quantitative calibration.

[0044] Optionally, the center of the PET long axial field of view quantitative correction device fixed on the bed board is adjusted to coincide with the ISO center, including: adjusting the center of the PET long axial field of view quantitative correction device fixed on the bed board to coincide with the ISO center based on the reference laser line provided by the CT laser lamp.

[0045] Optionally, the attenuation correction includes: bed board attenuation correction, tissue attenuation correction and motion attenuation correction.

[0046] Optionally, attenuation correction is done based on the CT scan, including:

[0047] Obtain attenuation coefficient based on CT scan;

[0048] generating an attenuation map based on the screening coefficients;

[0049] Apply the attenuation map to the raw PET data to complete the attenuation correction.

[0050] This embodiment provides a PET long axial field of view quantitative calibration method, which has the following advantages:

[0051] Improve the accuracy of diagnosis: The quantitative correction method provided by the present invention adds the step of attenuation correction, which can help doctors better understand the information in the image. Through quantitative analysis, the severity of the disease can be more accurately assessed, thereby providing stronger support for doctors' diagnosis and treatment.

[0052] Improve image quality: The quantitative correction method provided by the present invention can further improve the accuracy of the original data of the PET image and improve the quality of the PET image, so that doctors can see the location and size of the lesion more clearly.

[0053] Adaptability of quantitative correction of long axial field of view: The phantom device provided by the present invention, which can be placed on the bed and can adjust the posture of 6 degrees of freedom, can adjust the corresponding length according to the actual length of the axial field of view, and realize high-precision quantitative correction of axial field of view of any length. In addition, the content of the present invention is not only applicable to PET equipment, but also to quantitative correction of other multi-mode imaging equipment of nuclear medicine, and has the advantage of wide applicability.

[0054] Stable connection and support of the phantom device: The prior art is to suspend the phantom device on the front end of the bed board. Due to the need for a long axial field of view, the phantom device will have a large mass after filling, resulting in a significant increase in the external force and torque it bears, and higher requirements for its rigidity and strength. However, it is difficult to achieve due to the mechanical properties and molding process of acrylic or non-metallic materials. The present invention places the phantom device on the bed board and has a reliable connection and support with the bed board, which can avoid motion artifacts caused by shaking during attenuation correction to the greatest extent, while reducing the low correction accuracy caused by the unadjustable eccentricity caused by its deformation and the risk of leakage of radionuclides due to damage to the phantom device due to large external forces.

[0055] In general, compared with related technologies, it not only improves the correction accuracy and device stability, but can also be used for high-precision quantitative correction of long axial fields of view, improves image quality, and has obvious advantages.

[0056] Second, as Figure 2 As shown, this embodiment provides a PET long-axial field of view quantitative correction device, including: a cylindrical mold body, a water outlet and a water inlet are arranged on a bottom surface of the cylindrical mold body; a front support seat and a rear support seat are arranged on both sides of the cylindrical mold body, and are used to fix the cylindrical mold body; a front adjustment seat and a rear adjustment seat are respectively connected to the front support seat and the rear support seat; an x-direction adjustment and locking knob, a y-direction adjustment knob and a z-direction adjustment and locking knob are arranged on the front adjustment seat and the rear adjustment seat, and are used to adjust the positions of the front adjustment seat and the rear adjustment seat.

[0057] Optionally, a longitudinal reference line and a transverse reference line are provided on the cylindrical mold body to provide references for the correction device in the vertical direction and the horizontal direction respectively.

[0058] The horizontal reference line usually refers to the reference line of the phantom on the horizontal plane. This line helps to correct in the horizontal direction, ensure the geometric accuracy of image reconstruction, and avoid image distortion caused by equipment error.

[0059] The longitudinal reference line refers to the reference line of the phantom in the vertical direction. This line is also used for calibration and to ensure the accuracy of imaging in the vertical direction and to ensure image consistency at different levels.

[0060] Optionally, the correction device is fixed on the bed board by cooperating with the bed board locking knob through a bed board connector.

[0061] The role of the phantom device provided in this embodiment is to perform regular calibration on the performance of the device, which can effectively reduce the impact of factors such as device performance and environment on the accuracy of the original data, thereby improving the accuracy of the correction and the stability of the results.

[0062] The imaging area of ​​the device is made of a barrel-shaped acrylic material that is hollow inside and can be filled with 18F-FDG. It also has a certain pressure-bearing capacity and is sealed to maximize the accuracy and safety of the correction.

[0063] The device is placed on a bed board and has a connection and support interface with the bed board, which can realize stable connection and support of the device and ensure that no motion artifacts occur during the attenuation correction process.

[0064] The device can achieve 6-DOF posture adjustment, ensuring that its center coincides with the ISO center, thereby improving correction accuracy.

[0065] Specifically, the phantom device is inserted into the bed board 13 through the bed board connector 8 to complete the preliminary connection, ensuring that the front adjustment seat 15 and the rear adjustment seat 10 are fully in contact with the upper surface of the bed board 13 to ensure full support of the phantom device. The contact can be further connected through the interface inherent in the upper surface of the bed board to connect with other accessories, or it can be limited to ensure that the cross-sectional shape of the contact surface is consistent. The infusion and exhaust of 18F-FDG are completed through the water inlet 6 and the drain port 5. The water inlet 6 and the drain port 5 both have a one-way self-sealing function. The phantom device is further firmly connected to the bed board through the bed board locking knob 7. The phantom device is moved to the built-in laser light area of ​​CT through the movement of the bed board, and the laser light is turned on. By confirming the non-coincidence between the longitudinal reference line 2 and the transverse reference line 14 and the laser line, the position coarse adjustment plan of the phantom device can be quantitatively calibrated. The front support seat 1 falls on the front adjustment seat 15, the rear support seat 4 falls on the rear adjustment seat 10, and the front support seat 1 and the rear support seat 4 are rigidly connected to the barrel-shaped mold, that is, the position of the barrel-shaped mold in the imaging area can be completed by adjusting the positions of the front support seat 1 and the rear support seat 4, ensuring the accuracy of overlap. The z-direction translation freedom adjustment of the barrel-shaped mold 3 can be adjusted by the paired z-direction adjustment and locking knobs 9, and the z-direction position locking of the barrel-shaped mold 3 can be achieved. The x-direction translation and the y-direction rotation freedom adjustment of the barrel-shaped mold 3 can be adjusted by the paired x-direction adjustment and locking knobs 11, and the x-direction position locking of the barrel-shaped mold 3 can be achieved. The y-direction translation and the x-direction and z-direction rotation freedom adjustment of the barrel-shaped mold 3 can be adjusted by the paired y-direction adjustment knobs 12. The above posture adjustment amounts are all stepless adjustments, and can be adjusted in place at one time according to the feedback deviation amount, thereby improving the convenience of the adjustment operation.

[0066] In a third aspect, an embodiment of the present invention provides a computer-readable storage medium having a computer program stored thereon, which, when executed, implements a PET long axial field of view quantitative correction method as described in any one of the first aspects above.

[0067] In a fourth aspect, an embodiment of the present invention provides a storage device, including a storage medium and a processor, wherein the storage medium stores a computer program, and when the program is executed by the processor, a quantitative correction method for the long axial field of view of PET as described in any one of the first aspects above is implemented.

[0068] It will be appreciated by those skilled in the art that embodiments of the present invention may be provided as methods, systems or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Furthermore, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0069] Obviously, those skilled in the art can make various modifications and variations to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention should also include these modifications and variations.

[0070] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may alter, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A quantitative correction method for PET long axial field of view, characterized in that: include: Coarsely adjust the center of the PET long-axis field of view quantitative correction device fixed on the bed board to coincide with the ISO center; Using PET images, determine the deviation between the center of the calibration device and the ISO center; Fine-tune the correction device according to the deviation so that the center of the correction device coincides with the ISO center; Attenuation correction is done based on CT scans; Perform PET quantitative calibration scan and complete PET long axial field of view quantitative calibration.

2. A PET long axial field of view quantitative correction method according to claim 1, characterized in that: The center of the PET long axial field of view quantitative correction device fixed on the bed board is adjusted to coincide with the ISO center, including: based on the reference laser line provided by the CT laser lamp, the center of the PET long axial field of view quantitative correction device fixed on the bed board is adjusted to coincide with the ISO center.

3. A PET long axial field of view quantitative correction method according to claim 2, characterized in that: The attenuation correction includes: bed plate removal attenuation correction, tissue attenuation correction and motion attenuation correction.

4. A PET long axial field of view quantitative correction method according to claim 3, characterized in that: Attenuation correction is done based on the CT scan, including: Obtain attenuation coefficient based on CT scan; generating an attenuation map based on the screening coefficients; Apply the attenuation map to the raw PET data to complete the attenuation correction.

5. A PET long axial field of view quantitative correction device, characterized in that: include: A cylindrical mold body, wherein a water outlet and a water inlet are arranged on a bottom surface of the cylindrical mold body; A front support seat and a rear support seat are arranged on both sides of the cylindrical mold body and are used to fix the cylindrical mold body; A front adjustment seat and a rear adjustment seat are connected to the front support seat and the rear support seat respectively; The x-direction adjustment and locking knob, the y-direction adjustment knob and the z-direction adjustment and locking knob are arranged on the front adjustment seat and the rear adjustment seat, and are used to adjust the positions of the front adjustment seat and the rear adjustment seat.

6. A PET long axial field of view quantitative correction device according to claim 5, characterized in that: The cylindrical mold body is provided with a longitudinal reference line and a transverse reference line, which provide references for the correction device in the vertical direction and the horizontal direction respectively.

7. The PET long axial field of view quantitative correction device according to claim 5, characterized in that: The correction device is matched with the bed board locking knob through the bed board connector to be fixed on the bed board.

8. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the method for quantitatively correcting the long axial field of view of PET as described in any one of claims 1 to 4 is implemented.

9. A storage device comprising a storage medium and a processor, wherein the storage medium stores a computer program, wherein: When the processor executes the computer program, the method for quantitatively correcting the long axial field of view of PET as described in any one of claims 1 to 4 is implemented.

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