阅读说明：本技术 一种骨密度测量系统及其测量方法 (Bone mineral density measuring system and measuring method thereof ) 是由 梁海娟 王今雨 孙涛 于 2021-07-06 设计创作，主要内容包括：本发明涉及一种骨密度测量系统及其测量方法,其中系统包括一个含有定量计算机体层摄影模块的CT扫描仪,独立的单标定体模和一个定量计算机体层摄影术数据图像处理程序,设备之间可通过网络或移动存储的方式进行数据交互；定量计算机体层摄影术数据图像处理程序的数据接收模块接受来自CT扫描仪的医学数字成像,通过骨密度分析模块测量患者的骨密度；本发明通过CT扫描仪,QCT程度以及单标定体模相结合采用体模和患者分离的异步方式进行扫描,测量准确性更高,测量更为方便,保证患者舒适度。(The invention relates to a bone density measuring system and a measuring method thereof, wherein the system comprises a CT scanner containing a quantitative computer tomography module, an independent single calibration phantom and a quantitative computer tomography data image processing program, and data interaction can be carried out between devices in a network or mobile storage mode; a data receiving module of a quantitative computed tomography data image processing program receives medical digital imaging from a CT scanner, and bone density of a patient is measured through a bone density analysis module; according to the invention, the CT scanner, the QCT degree and the single calibration phantom are combined to scan in an asynchronous mode of separating the phantom from the patient, so that the measurement accuracy is higher, the measurement is more convenient, and the comfort of the patient is ensured.)

1. A bone density measuring system is characterized by comprising a CT scanner containing a quantitative computer tomography module, an independent single calibration phantom and a quantitative computer tomography data image processing program, wherein data interaction can be carried out between the devices in a network or mobile storage mode; a data receiving module of the quantitative computed tomography data image processing program receives the medical digital imaging from the CT scanner and measures the bone density of the patient through a bone density analysis module.

2. The bone density measurement method according to claim 1, wherein the single calibration phantom is formed by quantitative mixing, pressing and molding of polyethylene, tricalcium phosphate and hydroxyapatite.

3. A bone density measurement method according to claim 2, characterized in that the ratio between polyethylene, tricalcium phosphate and hydroxyapatite in the single calibration phantom is 90:3: 7.

4. A method of bone density measurement using the bone density measurement system according to any one of claims 1 to 3,

firstly, a CT scanner is used for measuring CT values of a multi-calibration phantom, the multi-calibration phantom comprises a plurality of reference material columns, linear regression is carried out on the measured CT values and equivalent bone density values corresponding to the CT values, a linear model of the CT values and the bone density values is obtained, and a formula corresponding to the model is as follows:

BMD＝a*H_B+b

BMD in the formula is bone density value, H_BIs the CT value, a and b are the calculated slope and intercept;

placing a single calibration phantom in the center of a CT scanning bed, carrying out quantitative computed tomography scanning on the single calibration phantom corresponding to a single CT value, scanning to obtain an axial image, obtaining axial, coronal and sagittal images by using the axial image, selecting an interested area on the image, and calculating a calibrated slope and an intercept according to a linear model and the CT mean value and the predicted bone density value of the single calibration phantom;

the patient places the body in the center of the scanning field, and a CT scanner obtains a sufficient amount of axial images; acquiring corresponding coronal position images and corresponding out-of-shape position images by using the axial position images, and manually selecting an interested area; and analyzing and obtaining the CT mean value of the region of interest by using a quantitative computer tomography data image processing program, and substituting the CT mean value into the linear model of the calibrated CT value and the bone density value to obtain the bone density value of the patient.

5. The bone density measurement method according to claim 4, wherein when the single calibration phantom is scanned, the scanning range comprises the position from 1.2cm at the upper end to 1.2cm at the lower end of the phantom, so that the influence of impurities existing at the edge of the single calibration phantom is eliminated.

6. A bone density measurement method according to claim 4, characterized in that when the scanning is set to 2.5mm layer thickness and the thread pitch is 1.0, the single calibration phantom scanning obtains 70 layers of axial images.

7. The method of claim 4, wherein the bone density analysis result is generated by calculating the standard deviation T of the patient bone density value and the average bone density value of the same-sex normal young person and the standard deviation Z of the patient bone density value and the bone density value of the same-sex normal same-age person using a quantitative computed tomography data image processing program.

8. The bone density measurement method according to claim 4, wherein during calibration, the single calibration phantom is longitudinally placed in the center of the CT scanning bed, so that the single calibration phantom is ensured to be within the scannable range of the CT scanner; the bed height is adjusted by utilizing the CT collimation line, so that the single calibration phantom is positioned at the center of the scanning field; carrying out quantitative computed tomography scanning on the single calibration phantom, carrying out multi-plane reconstruction on the obtained axial images, sequentially superposing all the axial images, carrying out image recombination on coronal and sagittal positions, and selecting an interested region on the obtained axial, coronal and sagittal images.

9. The bone density measuring method as claimed in claim 4, wherein the bone density of the patient is measured by centering the body of the patient in the scanning field and obtaining a sufficient number of axial images by the CT scanner; and performing multi-plane reconstruction on the obtained axial position image, obtaining corresponding coronal position and out-of-shape position images, and manually selecting the region of interest.

Technical Field

The invention relates to the technical field of medical image processing and application, in particular to a bone density measuring system and a bone density measuring method.

Background

Osteoporosis is a systemic bone disease characterized by a decrease in bone mass and a change in bone tissue microstructure in a unit volume of bone, which can cause increased systemic bone fragility, decreased bone strength, and increased risk of fracture in a patient. The most important evaluation index of osteoporosis is Bone Density (BMD). Bone density measurement methods have been developed over decades and currently there are dual-energy X-ray absorption methods, ultrasound measurements, quantitative CT methods, etc. Quantitative CT examination to determine BMD is currently a very good method to measure volumetric BMD.

The BMD is determined by the quantitative CT examination at present by adopting a synchronous scanning multi-calibration bone density phantom method, wherein synchronous scanning is adopted to lift and bend the legs and knees of a patient, the back or the hip of the patient is tightly attached to a phantom as much as possible, no gap exists between the back and the hip of the patient, the patient with limited activity of the lumbar and the hip or the patient with deformity of a relevant part is difficult to match with an examination body position, the placing position of the phantom relative to a human body has relevant requirements, and the phantom has high density and is easy to generate artifacts on a shot CT image; the multi-calibration phantom needs to calibrate various different bone densities, so compared with a single calibration phantom, the multi-calibration phantom has the advantages of more complex manufacturing process, higher manufacturing cost and larger volume.

Disclosure of Invention

One of the purposes of the invention is to provide a bone density measuring system aiming at the defects of the prior art, the asynchronous mode of separating a phantom and a patient is adopted for scanning by combining a CT scanner, a QCT degree and a single calibration phantom, the measurement accuracy is higher, the measurement is more convenient, and the comfort level of the patient is ensured.

The technical solution of the invention is as follows:

a bone density measuring system comprises a CT scanner containing a quantitative computer tomography module, an independent single calibration phantom and a Quantitative Computer Tomography (QCT) data image processing program, wherein data interaction can be carried out between the devices in a network or mobile storage mode; the data receiving module of the QCT program accepts digital medical imaging (Dicom) from a CT scanner and measures bone density of the patient by a bone density analysis module.

Preferably, the single calibration phantom is formed by quantitatively mixing, pressing and molding polyethylene, tricalcium phosphate and hydroxyapatite.

Preferably, the ratio between the polyethylene, the tricalcium phosphate and the hydroxyapatite in the single calibration phantom is 90:3: 7.

The invention also aims to provide a bone density measuring method aiming at the defects of the prior art.

The technical solution of the invention is as follows:

a method of bone density measurement comprising

Firstly, a CT scanner is used for measuring CT values of a multi-calibration phantom, the multi-calibration phantom comprises a plurality of reference material columns, linear regression is carried out on the measured CT values and equivalent bone density values corresponding to the CT values, a linear model of the CT values and the bone density values is obtained, and a formula corresponding to the model is as follows:

BMD＝a*H_B+b

BMD in the formula is bone density value, H_BIs the CT value, a and b are the calculated slope and intercept;

placing a single calibration phantom in the center of a CT scanning bed, carrying out quantitative computed tomography scanning on the single calibration phantom corresponding to a single CT value, scanning to obtain an axial image, obtaining axial, coronal and sagittal images by using the axial image, selecting an interested area on the image, and calculating a calibrated slope and an intercept according to a linear model and the CT mean value and the predicted bone density value of the single calibration phantom;

the patient places the body in the center of the scanning field, and a CT scanner obtains a sufficient amount of axial images; acquiring corresponding coronal position images and corresponding out-of-shape position images by using the axial position images, and manually selecting an interested area; and analyzing and obtaining the CT mean value of the region of interest by using a quantitative computer tomography data image processing program, and substituting the CT mean value into the linear model of the calibrated CT value and the bone density value to obtain the bone density value of the patient.

In order to ensure the accuracy of bone density detection, the single calibration phantom of the invention is scanned once a month and the linear model of CT value and bone density value is calibrated.

The determination method is mainly used for determining the cancellous bone of the vertebral body, the update conversion rate of the cancellous bone is far greater than that of the cortical bone, and metabolic diseases can be reflected early and the treatment effect can be reflected sensitively.

Wherein, the proportion of the polyethylene, the tricalcium phosphate and the hydroxyapatite in the single calibration phantom is 90:3:7, and the matching degree of the proportion value and the measurement software is the highest.

Preferably, when the single calibration phantom is scanned, the scanning range comprises the position from 1.2cm at the upper end of the phantom to 1.2cm at the lower end of the phantom, so that the influence of impurities existing at the edge of the single calibration phantom is eliminated.

Preferably, when the scanning is set to be 2.5mm in layer thickness and 1.0 in thread pitch, the single calibration phantom scanning obtains 70 layers of axial images.

Preferably, the bone density analysis result is generated by calculating a standard deviation T value of the patient bone density value and the average value of the bone density values of the same sex normal young people and a standard deviation Z value of the patient bone density value and the bone density value of the same sex normal elderly people by using a quantitative computer tomography data image processing program.

Preferably, during calibration, the single calibration phantom is longitudinally placed in the center of the CT scanning bed, so that the single calibration phantom is ensured to be within the scannable range of the CT scanner; the bed height is adjusted by utilizing the CT collimation line, so that the single calibration phantom is positioned at the center of the scanning field; carrying out quantitative computed tomography scanning on the single calibration phantom, carrying out multi-plane reconstruction on the obtained axial images, sequentially superposing all the axial images, carrying out image recombination on coronal and sagittal positions, and selecting an interested region on the obtained axial, coronal and sagittal images.

As still another preferred mode, when measuring the bone density of the patient, the body of the patient is placed in the center of the scanning field, and a sufficient amount of axial images are obtained by the CT scanner; and performing multi-plane reconstruction on the obtained axial images, obtaining corresponding coronal and out-of-shape images thereof, and manually selecting the region of interest.

The invention has the beneficial effects that:

the invention adopts a single calibration phantom, so that the invention has the advantages of relatively more calibration phantoms, simple manufacturing process, low manufacturing cost, small volume, capability of achieving large-scale production, good cost reduction and convenient transportation and storage;

in addition, the asynchronous single-calibration body model bone density measuring method adopts an asynchronous mode of separating the body model from the patient for scanning, and the whole scanning process of the patient does not need the body model to participate, so that the patient does not need to be matched with the body position in which the body model participates, and the CT image of the patient does not generate artifacts due to the body model;

the method has a quality control calibration process, so that the accuracy of the measurement result of the bone density of the asynchronous single calibration body model can be ensured; and the test proves that the asynchronous single-calibration body model bone density measurement result and the synchronous multi-calibration body model bone density measurement result have no great difference, so the method is suitable for large-scale application in the field of bone density measurement.

In conclusion, the invention has the advantages of low cost, convenient measurement, high measurement accuracy and the like, and is particularly suitable for the technical field of bone mineral density measurement equipment.

Drawings

The invention is further described below with reference to the accompanying drawings:

figure 1 is a schematic view of a single calibration phantom CT scan;

fig. 2 is an image of a single calibration phantom in bone density analysis software.

The specific implementation mode is as follows:

the technical scheme in the embodiment of the invention is clearly and completely explained by combining the attached drawings.

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are illustrative and intended to be illustrative of the invention and are not to be construed as limiting the invention.

Example one

As shown in fig. 1 to 2, a bone density measuring system comprises a CT scanner with a quantitative Computed Tomography (CT) module, a single calibration phantom 101 and a Quantitative Computed Tomography (QCT) data image processing program, which are independent, and the devices can perform data interaction through a network or a mobile storage manner; the data receiving module of the QCT program accepts digital medical imaging (Dicom) from a CT scanner and measures bone density of the patient by a bone density analysis module.

Wherein the single calibration phantom 101 is formed by quantitatively mixing, pressing and molding polyethylene, tricalcium phosphate and hydroxyapatite.

The ratio of the polyethylene, the tricalcium phosphate and the hydroxyapatite in the single calibration phantom 101 is 90:3:7, and the ratio value is a parameter value which is obtained by multiple experiments and has the highest matching degree with a bone density measurement method.

Example two

A method of bone density measurement comprising

Firstly, a CT scanner is used for measuring CT values of a multi-calibration phantom, the multi-calibration phantom comprises a plurality of reference material columns, linear regression is carried out on the measured CT values and equivalent bone density values corresponding to the CT values, a linear model of the CT values and the bone density values is obtained, and a formula corresponding to the model is as follows:

BMD＝a*H_B+b

BMD in the formula is bone density value, H_BIs the CT value, a and b are the calculated slope and intercept;

placing a single calibration phantom 101 in the center of a CT scanning bed, carrying out quantitative computed tomography scanning on the single calibration phantom corresponding to a single CT value to obtain an axial image, obtaining axial, coronal and sagittal images by using the axial image, selecting an interested area on the images, and calculating a calibrated slope and an intercept according to a linear model and the CT mean value and the predicted bone density value of the single calibration phantom;

when the single calibration phantom 101 is scanned, the scanning range comprises the position from 1cm at the upper end to 1cm at the lower end of the phantom, and the set range can eliminate the influence of impurities on the edge of the single calibration phantom, so that the scanning result is more accurate.

When the scanning is set to be 2.5mm in layer thickness and the thread pitch is 1.0, the single calibration phantom is scanned to obtain 70 layers of axial position images, of course, other scanning layer thickness values and thread pitch values can be set to obtain axial position images of different layers, and the set value is only one of the optimization of the embodiment.

And calculating the standard deviation T value of the average value of the bone density values of the patient and the bone density values of the same sex normal young people and the standard deviation Z value of the bone density values of the patient and the same sex normal same age people by using a quantitative computer tomography data image processing program to generate a bone density analysis result.

When the calibration is carried out, the single calibration phantom is longitudinally placed in the center of the CT scanning bed, so that the single calibration phantom is ensured to be in the scannable range of the CT scanner; the bed height is adjusted by utilizing the CT collimation line, so that the single calibration phantom is positioned at the center of the scanning field; carrying out quantitative computed tomography scanning on the single calibration phantom, carrying out multi-plane reconstruction on the obtained axial images, sequentially superposing all the axial images, carrying out image recombination on coronal and sagittal positions, and selecting an interested region on the obtained axial, coronal and sagittal images.

The procedure for lumbar spine examination for the patient was as follows:

1. the patient places the body in the center of the scan field and a sufficient number of axial images are acquired by the CT scanner.

2. And performing multi-plane reconstruction on the obtained axial images, obtaining corresponding coronal position images and corresponding out-of-range position images, and manually selecting an interested area in one of the first lumbar vertebra, the second lumbar vertebra, the third lumbar vertebra and the fourth lumbar vertebra.

3. And analyzing and obtaining the CT mean value of the region of interest by using a quantitative computer tomography data image processing program, and substituting the CT mean value into the linear model of the calibrated CT value and the bone density value to obtain the lumbar vertebrae density value of the patient.

4. And calculating the standard deviation T value of the bone density value of the patient and the average value of the bone density of the same sex normal young person in the program, and calculating the standard deviation Z value of the bone density value of the patient and the bone density value of the same sex normal same age person in the program to generate a lumbar vertebrae density analysis result.

EXAMPLE III

Wherein the same or corresponding components as those in embodiment two are designated by the same reference numerals as those in embodiment two, and for the sake of convenience, only the points of difference from embodiment two will be described below; the third embodiment is different from the second embodiment in that:

the procedure for the patient hip examination is as follows:

1. the patient's toes are pronated and the body is centered in the field of scanning, and a sufficient number of axial images are acquired by the CT scanner.

2. And performing multi-plane reconstruction on the obtained axial images, obtaining corresponding coronal and desperate images thereof, and selecting a region of interest in the hip.

3. The patient's hip bone density value can be obtained by analyzing and obtaining the CT mean value of the region of interest using a quantitative computed tomography data image processing program, and substituting the CT mean value into the linear model of the calibrated CT value and bone density value.

4. And calculating the standard deviation T value of the bone density value of the patient and the average value of the bone density of the same sex normal young person in the program, and calculating the standard deviation Z value of the bone density value of the patient and the bone density value of the same sex normal same age person in the program to generate a hip bone density analysis result.

In the description of the present invention, it is to be understood that the terms "front-back", "left-right", and the like indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience in describing the present invention and simplifying the description, but do not indicate or imply that the referred device or component must have a specific orientation, be constructed in a specific orientation, and be operated, and thus should not be construed as limiting the invention.

Of course, in this disclosure, those skilled in the art will understand that the terms "a" and "an" should be interpreted as "at least one" or "one or more," i.e., in one embodiment, a number of an element may be one, and in another embodiment, a number of the element may be plural, and the terms "a" and "an" should not be interpreted as limiting the number.

The present invention is not limited to the above-described embodiments, and it should be noted that various changes and modifications can be made by those skilled in the art without departing from the structure of the present invention, and these changes and modifications should be construed as the scope of the present invention, which does not affect the effect and practicality of the present invention.