Method, device and computer program for determining gray value of specific area of detected object

Abstract

The invention discloses a method and device for determining a gray value of a specific area of a detected object, a computer program, a computer readable storage medium and medical imaging equipment. The method for determining the gray value of the specific area of the examined object comprises the following steps: carrying out tomography on a correction die body on an examination bed; storing a cross-sectional image of the correction die body; performing tomography on the detected object; and according to the cross-sectional image of the correction die body and the cross-sectional image of the detected object, determining a gray value of a specific area of the detected object. According to the method, the workflow can be simplified, and the volume bone mineral density which is high in accuracy and not affected by height, weight, spinal hyperplasia, degeneration and vascular calcification is provided with low dosage.

Description

[0001] Nouns and pronouns relating to persons in this patent application are not limited to a specific gender. Technical Field

[0002] The present invention relates to medical imaging, and in particular to bone density measurement. Background Art

[0003] Currently, when using CT to measure bone density, a specific reference phantom and mattress are required. The reference phantom is made of a stable solid material that contains water and a sample of a material equivalent to bone. The mattress has a groove suitable for accommodating the reference phantom. When measuring bone density, the reference phantom is placed in the groove and covered with a gel pad. The subject lies on the gel pad and undergoes a tomographic scan. The gel pad can reduce lordosis and prevent the radiation hardening effect caused by air gaps. The scanning and evaluation software analyzes the tomographic images containing both the human body and the reference phantom and calculates indicators such as bone density.

[0004] If a conventional CT scan is performed, the reference phantom and mattress need to be removed. This switching between conventional scans and bone density scans will increase the workload and reduce the utilization rate of the CT machine. Summary of the invention

[0005] In view of this, the present invention proposes a method, an apparatus, a computer program, a computer-readable storage medium and a medical imaging device for determining the grayscale value of a specific area of ​​an object under examination.

[0006] According to a first aspect of the present invention, there is provided a method for determining the grayscale value of a specific area of ​​an object under examination, comprising: performing a tomographic scan on a correction phantom on an examination bed; storing a tomographic image of the correction phantom; performing a tomographic scan on the object under examination; and determining the grayscale value of the specific area of ​​the object under examination based on the tomographic image of the correction phantom and the tomographic image of the object under examination.

[0007] In one embodiment, a time difference between the tomographic image of the calibration phantom and the tomographic image of the subject is smaller than a preset range.

[0008] In one embodiment, the preset range is one week, two weeks or four weeks.

[0009] In one embodiment, the method further comprises determining one or more of the bone density, T value and Z value of the specific area of ​​the subject according to the grayscale value of the specific area of ​​the subject.

[0010] According to a second aspect of the present invention, a computer program is provided, which can implement the steps of the above method when executed by a processor.

[0011] According to a third aspect of the present invention, there is provided a computer-readable storage medium having a computer program stored thereon, which can implement the steps of the above-mentioned method when executed by a processor.

[0012] According to a fourth aspect of the present invention, there is provided a device for determining the grayscale value of a specific area of ​​an object under examination, comprising: a phantom scanning unit, configured to perform a tomographic scan on a correction phantom on an examination bed; a storage unit, configured to store a tomographic image of the correction phantom; an object scanning unit, configured to perform a tomographic scan on the object under examination; and a grayscale value determination unit, configured to determine the grayscale value of the specific area of ​​the object under examination based on the tomographic image of the correction phantom and the tomographic image of the object under examination.

[0013] In one embodiment, a time difference between the tomographic image of the calibration phantom and the tomographic image of the subject is smaller than a preset range.

[0014] In one embodiment, the preset range is one week, two weeks or four weeks.

[0015] In one embodiment, the device comprises a bone density determination unit configured to determine one or more of the bone density, T value and Z value of the specific area of ​​the subject according to the grayscale value of the specific area of ​​the subject.

[0016] According to a fifth aspect of the present invention, there is provided a medical imaging device comprising the apparatus as described above.

[0017] The method, device, computer program, computer-readable storage medium and computer tomography equipment for determining the grayscale value of a specific area of ​​an object under examination of the present invention can simplify the workflow and provide volumetric bone density with high accuracy and at a low dose that is not affected by height and weight, spinal hyperplasia, degeneration and vascular calcification. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings so that the above and other features and advantages of the present invention will be more apparent to those skilled in the art. In the accompanying drawings:

[0019] Figure 1 The figure is a schematic flow chart of a method for determining a grayscale value of a specific area of ​​an object under inspection according to an embodiment of the present invention.

[0020] Figure 2 The figure is a schematic structural block diagram of a device for determining the grayscale value of a specific area of ​​an object under inspection according to an embodiment of the present invention.

[0021] In the above drawings, the reference numerals used are as follows:

[0022] DETAILED DESCRIPTION

[0023] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention is further described in detail with reference to the following embodiments.

[0024] Figure 1 FIG. 1 is a schematic flow chart of a method 100 for determining the grayscale value of a specific area of ​​an object under examination according to an embodiment of the present invention. Figure 1 As shown, the method 100 for determining the grayscale value of a specific area of ​​the subject includes step S102, step S104, step S106, and step S108.

[0025] In step S102, a tomographic scan is performed on the correction phantom on the examination bed. The correction phantom may not be placed in the groove of the special mattress, but may be placed directly on the general examination bed. In the present application, "tomography" is not limited to computer tomography, but generally refers to a section perpendicular to the longitudinal direction of the phantom or the object under examination, and has nothing to do with the specific imaging method. "Tomographic scanning" can be implemented by CT machines, MR machines, etc.

[0026] In step S104, the tomographic image of the calibration phantom is stored.

[0027] In step S106, a tomographic scan is performed on the subject.

[0028] In step S108, the grayscale value of a specific area of ​​the object under examination is determined based on the tomographic image of the correction phantom and the tomographic image of the object under examination. The specific area is, for example, a bone. It can be seen that the correction phantom and the object under examination are not tomographically scanned at the same time. Since the tomographic scans of the correction phantom and the object under examination may not use the same scanning parameters, and the physical states of imaging devices such as CT machines (such as focal positions, etc.) may not be consistent, the grayscale value of the specific area of ​​the object under examination determined may have certain errors. Nevertheless, in the screening scenario, such accuracy is acceptable.

[0029] In order to reduce the error, the time difference between the tomographic image of the correction phantom and the tomographic image of the object under examination may be required to be less than a preset range, such as one week, two weeks or four weeks, which can be customized by the user. Therefore, step S102 may be performed regularly.

[0030] The method 100 for determining the grayscale value of a specific area of ​​the object under examination may further include step S110 .

[0031] In step S110, one or more of the bone density, T value and Z value of the specific area of ​​the subject is determined according to the gray value of the specific area of ​​the subject. The bone density, T value and Z value can be calculated according to the gray value using existing technology.

[0032] By adopting the method of the present invention, no matter whether the subject is undergoing bone density screening or scanning for other purposes, the examination bed is the same, and there is no need to frequently switch between a mattress with grooves and a general mattress.

[0033] According to a second aspect of the present invention, a computer program is provided, which, when executed by a processor, can implement the steps of the method 100 for determining the grayscale value of a specific area of ​​an object under examination.

[0034] According to a third aspect of the present invention, there is provided a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, can implement the steps of the method 100 for determining the grayscale value of a specific area of ​​an object under examination.

[0035] According to a fourth aspect of the present invention, there is provided an apparatus 200 for determining the grayscale value of a specific region of an object under examination. Figure 2 FIG. 2 is a schematic structural block diagram of an apparatus 200 for determining the grayscale value of a specific area of ​​an object under inspection according to an embodiment of the present invention. Figure 2 As shown, the device 200 for determining the grayscale value of a specific area of ​​an object under examination includes a phantom scanning unit 202 , a storage unit 204 , an object scanning unit 206 , and a grayscale value determining unit 208 .

[0036] The phantom scanning unit 202 is configured to perform a tomographic scan on the correction phantom on the examination bed. The correction phantom may not be placed in the groove of the special mattress, but may be directly placed on the general examination bed.

[0037] The storage unit 204 is configured to store the tomographic image of the calibration phantom.

[0038] The object scanning unit 206 is configured to perform tomography scanning on the object under examination.

[0039] The gray value determination unit 208 is configured to determine the gray value of a specific area of ​​the object under examination based on the tomographic image of the correction phantom and the tomographic image of the object under examination. The specific area is, for example, a bone. It can be seen that the correction phantom and the object under examination are not tomographically scanned at the same time. Since the tomographic scans of the correction phantom and the object under examination may not use the same scanning parameters, and the physical state of the CT machine (such as the focus position, etc.) may not be consistent, the gray value of the specific area of ​​the object under examination determined may have a certain error. Nevertheless, in the screening scenario, such accuracy is acceptable.

[0040] In order to reduce the error, the time difference between the tomographic image of the calibration phantom and the tomographic image of the object under examination may be required to be less than a preset range, such as one week, two weeks or four weeks. Therefore, the phantom scanning unit 202 may periodically perform tomographic scanning on the calibration phantom on the examination bed.

[0041] The apparatus 200 for determining the grayscale value of a specific region of the subject may further include a bone density determining unit 210. The bone density determining unit 210 is configured to determine one or more of the bone density, T value and Z value of the specific region of the subject according to the grayscale value of the specific region of the subject.

[0042] By using the device for determining the grayscale value of a specific area of ​​an object under examination of the present invention, the examination bed is the same whether the object under examination is undergoing bone density screening or scanning for other purposes, and there is no need to frequently switch between a mattress with grooves and a general mattress.

[0043] According to a fifth aspect of the present invention, there is provided a medical imaging device comprising a device 200 for determining a grayscale value of a specific area of ​​an object under examination.

[0044] The present invention can use three-dimensional volume CT data to measure the true volume bone density. Compared with the area bone density measured by other projection technologies (such as dual-energy X-ray absorptiometry), QCT (Quantitative Computed Tomography) has its unique advantages:

[0045] Studies have shown that QCT has the characteristics of high accuracy and strong repeatability. QCT has a higher detection rate for lumbar osteoporosis than dual-energy X-ray absorptiometry (DXA).

[0046] QCT measures vBMD (volumetric bone mineral density), which is not affected by height and weight. QCT measures vertebral cancellous bone BMD, which is not affected by spinal hyperplasia, degeneration and vascular calcification. QCT has more advantages, especially in the elderly population;

[0047] QCT scans are performed in low-dose mode as much as possible. In most cases, QCT is performed simultaneously with clinical CT scans. One scan can produce multiple results without increasing radiation dose and scanning time.

[0048] In recent years, the international research and clinical application of QCT in osteoporosis has received increasing attention, and QCT technology has also expanded from bone density measurement to body composition and liver fat content measurement;

[0049] The current number of DXA in China is far from meeting clinical needs, while CT scanners are relatively popular in various medical institutions in China, and low-dose CT screening for lung nodules is widely used. Therefore, the technology of the present invention is particularly suitable for China and has good application prospects.

[0050] The method, device, computer program, computer-readable storage medium and medical imaging device of the present invention for determining the grayscale value of a specific area of ​​an object under examination can simplify the workflow and provide volumetric bone density with high accuracy and at a low dose that is not affected by height and weight, spinal hyperplasia, degeneration and vascular calcification.

[0051] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for determining the grayscale value of a specific area of ​​an object under inspection, comprising: Perform a tomographic scan of the calibration phantom on the examination table; storing a tomographic image of the calibration phantom; Performing a tomographic scan on the subject; The grayscale value of a specific area of ​​the object under examination is determined according to the tomographic image of the calibration phantom and the tomographic image of the object under examination.

2. The method according to claim 1, characterized in that: The time difference between the tomographic image of the correction phantom and the tomographic image of the object under examination is less than a preset range.

3. The method according to claim 1, characterized in that: The preset range is one week, two weeks or four weeks.

4. The method according to claim 1, characterized in that: The method also includes determining one or more of the bone density, T value and Z value of the specific area of ​​the subject according to the grayscale value of the specific area of ​​the subject.

5. A computer program, which, when executed by a processor, can implement the steps of the method according to any one of claims 1 to 4.

6. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the steps of the method described in any one of claims 1 to 4 can be implemented.

7. A device (200) for determining a grayscale value of a specific area of ​​an object under examination, comprising: A phantom scanning unit (202) configured to perform a tomographic scan on a calibration phantom on an examination bed; A storage unit (204) configured to store the tomographic image of the calibration phantom; an object scanning unit (206) configured to perform a tomographic scan on the object under examination; A grayscale value determination unit (208) is configured to determine the grayscale value of a specific area of ​​the subject according to the tomographic image of the calibration phantom and the tomographic image of the subject.

8. The device (200) according to claim 7, characterized in that The time difference between the tomographic image of the correction phantom and the tomographic image of the object under examination is less than a preset range.

9. The device (200) according to claim 7, characterized in that: The preset range is one week, two weeks or four weeks.

10. The device (200) according to claim 7, characterized in that: The device also includes a bone density determination unit (210) configured to determine one or more of the bone density, T value and Z value of the specific area of ​​the subject according to the grayscale value of the specific area of ​​the subject.

11. A medical imaging device, comprising the apparatus (200) according to any one of claims 7 to 10.

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