An ultrasonic backscattering bone density detection method and device

Abstract

The present invention relates to an ultrasonic backscattering bone density detection method and device. The method includes the following steps: S1. Obtain a reference signal and an ultrasonic backscattering signal passing through the bone to be measured. Based on the parallel acoustic wave ray theory, use the active set method of the deconvolution algorithm to solve deconvolution and calculate the ultrasonic echo transit time spectrum; S2. Obtain the spectral peak number density of the calculated ultrasonic echo transit time spectrum according to the ratio of the total number of peaks and the effective time window length. At the same time, calculate the spectral line area under the peak envelope curve within the effective time window length; S3. Perform linear regression analysis on the spectral peak number density and the spectral line area in S2 to obtain bone density information. Compared with the prior art, the present invention has the advantages of good measurement stability and the like.

Description

Technical Field

[0001] The present invention relates to the field of bone density detection, and particularly to an ultrasonic backscattering bone density detection method and device. Background Art

[0002] Dual-energy X-ray absorptiometry (DXA), peripheral quantitative computed tomography (pQCT), high-resolution magnetic resonance imaging (HR-MRI), etc. However, due to their high costs, strong ionizing radiation, or long image acquisition times, these techniques are difficult to promote and apply. In view of this situation, the prior art uses the ultrasonic transmission method to detect bone density. However, the ultrasonic transmission method requires two ultrasonic probes to be placed opposite to each other, which is inconvenient for measurement. At the same time, there are problems such as large ultrasonic signal attenuation and poor measurement stability. Summary of the Invention

[0003] The purpose of the present invention is to provide an ultrasonic backscattering bone density detection method and device to overcome the above-mentioned defects existing in the prior art.

[0004] The purpose of the present invention can be achieved through the following technical solutions:

[0005] An ultrasonic backscattering bone density detection method includes the following steps:

[0006] S1. Obtain a reference signal and an ultrasonic backscattering signal passing through the bone to be measured. Based on the parallel acoustic wave ray theory, use the active set method of the deconvolution algorithm to solve the deconvolution and calculate the ultrasonic echo transit time spectrum;

[0007] S2. Select the length of the effective time window, calculate the total number of peaks of the ultrasonic echo transit time spectrum within the length of the effective time window, obtain the peak number density of the ultrasonic echo transit time spectrum according to the ratio of the total number of peaks to the length of the effective time window. At the same time, draw the peak envelope curve of the ultrasonic echo transit time spectrum and calculate the spectral line area under the peak envelope curve within the length of the effective time window;

[0008] S3. Perform linear regression analysis on the peak number density and the spectral line area in S2 to obtain bone density information.

[0009] Furthermore, the expression of the peak number density is:

[0010]

[0011] where PKS represents the peak number density, pks represents the total number of peaks of the ultrasonic echo transit time spectrum within the length of the effective time window, and t w represents the length of the effective time window intercepted from the ultrasonic echo transit time spectrum.

[0012] Furthermore, the expression of the spectral line area is:

[0013]

[0014] Among them, S_PKS is the area under the spectrum line, pks represents the total number of peaks of the ultrasonic echo transit time spectrum within the effective time window length, and P_t i ) represents the proportion of the acoustic ray corresponding to the time point t i dt represents the time interval of the ultrasonic echo transit time spectrum signal, and i represents the i-th peak.

[0015] Furthermore, the steps of the linear regression analysis are specifically as follows: Calculate the correlation parameters between the peak number density and the area under the spectrum line of the ultrasonic echo transit time spectrum and the bone density information respectively based on the linear regression analysis algorithm. The correlation parameters include the correlation coefficient and the significance test value. When the significance test value is less than the preset threshold, determine the bone density information based on the correlation parameters at this time.

[0016] Furthermore, the bone density information includes one or more groups of the average trabecular bone number, the average trabecular bone spacing, and the bone surface / total volume, and the bone density information is used to calculate the bone density.

[0017] Furthermore, the reference signal is the signal reflected by the polished steel plate measured by the pulsed ultrasonic echo mode.

[0018] The present invention also provides an ultrasonic backscattering bone density detection device, including a memory, a processor, and a program stored in the memory. When the processor executes the program, the above method is implemented.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] (1) By deriving the ultrasonic echo transit time spectrum from the ultrasonic echo signal in the ultrasonic echo mode and performing linear regression analysis based on the relevant parameters of the peak number density and the area under the spectrum line of the ultrasonic echo transit time spectrum, the present invention obtains the bone density information, reduces the radiation risk, and saves the detection time and cost.

[0021] (2) By analyzing the backscattering signal in the time domain, the present invention does not need to consider the complex frequency response of the backscattering signal, nor does it need to consider the attenuation compensation of the signal, and can overcome the problems of large attenuation and poor measurement stability of the backscattering signal. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 is a flowchart of the present invention;

[0023] Figure 2 is the ultrasonic echo transit time spectra of three different bone volume fractions in the embodiment of the present invention. Among them, Figure 2 (a) is the ultrasonic echo transit time spectrum when the bone volume fraction is 34.8%,Figure 2 (b) is the ultrasonic echo transit time spectrum when the bone volume fraction is 24.29%; Figure 2 (c) is the ultrasonic echo transit time spectrum when the bone volume fraction is 16.12%;

[0024] Figure 3 shows the relationship between the PKS parameters and the bone structure information of the present invention, where Figure 3 (a) is the correlation between the PKS parameter and the average trabecular bone number, Figure 3 (b) is the correlation between the PKS parameter and the average trabecular bone spacing;

[0025] Figure 4 shows the relationship between the S_PKS parameters and the bone structure information of the present invention, where Figure 4 (a) is the correlation between the S_PKS parameter and the bone surface / total volume, Figure 4 (b) is the correlation between the S_PKS parameter and the average trabecular bone number. Detailed implementation manners

[0026] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. This embodiment is implemented on the premise of the technical solution of the present invention, and the detailed implementation manners and specific operation processes are given, but the protection scope of the present invention is not limited to the following embodiments.

[0027] The present invention provides an ultrasonic backscattering bone density detection method, and the flowchart of the method is as Figure 1 shown. The method includes the following steps:

[0028] Step S1, measure the reference signal reflected by the polished steel plate and the ultrasonic backscattering signal passing through the bone to be measured through the pulsed ultrasonic echo mode, and calculate the deconvolution result of the reference signal and the backscattering signal based on the parallel acoustic wave ray theory. Since the deconvolution operation is ill-posed, a regularization method needs to be used for solution. The active set algorithm is a kind of regularization method, which can be used to solve the deconvolution result of the signal to obtain the ultrasonic echo transit time spectrum;

[0029] Step S2, select the effective time window length, calculate the total number of peaks of the ultrasonic echo transit time spectrum within the effective time window length, and obtain the peak number density PKS of the calculated ultrasonic echo transit time spectrum according to the ratio of the total number of peaks to the effective time window length. At the same time, draw the peak envelope curve of the ultrasonic echo transit time spectrum, and calculate the spectral line area S_PKS of the peak envelope curve within the effective time window length;

[0030] Step S3: Perform linear regression analysis. The specific steps are as follows: Use the linear regression statistical analysis method to calculate the correlation parameters between PKS and S_PKS and the bone density information respectively. The correlation parameters include the correlation coefficient and the significance test value. When the significance test value is less than the preset threshold, determine the bone density information based on the correlation parameters at this time.

[0031] The expression for the spectral peak number density is:

[0032]

[0033] where PKS represents the spectral peak number density, pks represents the total number of peaks in the ultrasonic echo transit time spectrum within the effective time window length, and t w represents the effective time window length intercepted from the ultrasonic echo transit time spectrum.

[0034] The expression for the area under the spectral line is:

[0035]

[0036] where S_PKS is the area under the spectral line, pks represents the total number of peaks in the ultrasonic echo transit time spectrum within the effective time window length, P t i ) represents the proportion of the acoustic ray at time point t i , dt represents the time interval of the ultrasonic echo transit time spectrum signal, and i represents the i-th peak.

[0037] In S3, the bone density information includes one or more groups of the average trabecular bone number, the average trabecular bone spacing, and the bone surface / total volume. The bone density information is used to calculate the bone density. The correlation parameters include the correlation coefficient R and the significance test value p. The preset threshold can be 0.01 or 0.001. Generally, it is considered that p < 0.01 indicates a significant statistical difference, and p < 0.001 indicates an extremely significant statistical difference. The meanings of p < 0.01 and p < 0.001 are that the probability that the difference between samples is due to sampling is less than 0.01 and 0.001 respectively.

[0038] The advantage of the present invention is that it can derive the ultrasonic echo transit time spectrum from the ultrasonic echo signal in a relatively simple ultrasonic echo mode, directly infer the bone density based on the relevant parameters of the ultrasonic echo transit time spectrum, while reducing the radiation risk and saving the detection time and cost.

[0039] As Figure 2 shown, the vertical dotted line represents intercepting the effective signal by the time window, and the solid triangle symbol represents the peak of the ultrasonic echo transit time spectrum. Figure 2 (a)-(c) correspond to the ultrasonic echo transit time spectra when the bone volume fraction is 34.8%, when the bone volume fraction is 24.29%, and when the bone volume fraction is 16.12% respectively.

[0040] As Figure 3 shown Figure 3 (a) represents the correlation between PKS and the average trabecular bone number (Tb.N); (b) represents the correlation between PKS and the average trabecular bone spacing (Tb.Sp). Figure 4 (a) represents the correlation between S_PKS and bone surface / total volume (BS / TV); Figure 4 (b) represents the correlation between S_PKS and the average trabecular bone number (Tb.N).

[0041] The preferred specific embodiments of the present invention have been described in detail above. It should be understood that those of ordinary skill in the art can make many modifications and variations based on the concept of the present invention without creative efforts. Therefore, all technical solutions that can be obtained by those skilled in the art in the technical field according to the concept of the present invention through logical analysis, reasoning or limited experiments on the basis of the prior art should be within the protection scope determined by the claims.

Claims

1. An ultrasonic backscattering bone density detection method, characterized in that, Including the following steps: S1. Obtain the reference signal and the ultrasonic backscattering signal passing through the bone to be measured. Based on the parallel acoustic wave ray theory, use the active set method of the deconvolution algorithm to solve the deconvolution, and calculate the ultrasonic echo transit time spectrum; S2. Select the effective time window length, calculate the total number of peaks of the ultrasonic echo transit time spectrum within the effective time window length, and obtain the peak number density of the calculated ultrasonic echo transit time spectrum according to the ratio of the total number of peaks to the effective time window length. At the same time, plot the peak envelope curve of the ultrasonic echo transit time spectrum and calculate the spectral line area under the peak envelope curve within the effective time window length; S3. Perform linear regression analysis on the peak number density and the spectral line area in S2 to obtain bone density information; The expression for the peak number density is: Among them, PKS represents the spectral peak number density, pks represents the total number of peaks in the ultrasonic echo transit time spectrum within the effective time window length, and t w represents the effective time window length intercepted from the ultrasonic echo transit time spectrum; The expression for the spectral line area is: Among them, S_PKS is the area under the spectrum line, pks represents the total number of peaks in the ultrasonic echo transit time spectrum within the effective time window length, P(t i ) represents the proportion of the acoustic ray corresponding to the time point t i , dt represents the time interval of the ultrasonic echo transit time spectrum signal, and i represents the i-th peak.

2. The ultrasonic backscattering bone density detection method according to claim 1, wherein The specific steps of the linear regression analysis are as follows: Calculate the correlation parameters of the peak number density and the spectral line area with the bone density information respectively based on the linear regression analysis algorithm. The correlation parameters include the correlation coefficient and the significance test value. When the significance test value is less than the preset threshold, determine the bone density information based on the correlation parameters at this time.

3. The ultrasonic backscattering bone density detection method according to claim 2, characterized in that, The bone density information includes one or more groups of the average trabecular bone number, the average trabecular bone spacing, and the bone surface / total volume, and the bone density information is used to calculate the bone density.

4. The ultrasonic backscattering bone density detection method according to claim 1, wherein The reference signal is the signal reflected by the polished steel plate measured through the pulsed ultrasonic echo mode.

5. An ultrasonic backscattering bone density detection device, characterized in that, Including a memory, a processor, and a program stored in the memory, characterized in that when the processor executes the program, the following steps are implemented: S1. Obtain the reference signal and the ultrasonic backscattering signal passing through the bone to be measured. Based on the parallel acoustic wave ray theory, use the active set method of the deconvolution algorithm to solve the deconvolution, and calculate the ultrasonic echo transit time spectrum; S2. Select the effective time window length, calculate the total number of peaks of the ultrasonic echo transit time spectrum within the effective time window length, and obtain the peak number density of the calculated ultrasonic echo transit time spectrum according to the ratio of the total number of peaks to the effective time window length. At the same time, plot the peak envelope curve of the ultrasonic echo transit time spectrum and calculate the spectral line area under the peak envelope curve within the effective time window length; S3. Perform linear regression analysis on the peak number density and the spectral line area in S2 to obtain bone density information; The expression for the peak number density is: Among them, PKS represents the spectral peak number density, pks represents the total number of peaks in the ultrasonic echo transit time spectrum within the effective time window length, and t w represents the effective time window length intercepted from the ultrasonic echo transit time spectrum; The expression for the spectral line area is: Among them, S_PKS is the area under the spectrum line, pks represents the total number of peaks of the ultrasonic echo transit time spectrum within the effective time window length, P(t i ) represents the proportion of the acoustic ray corresponding to the time point t i , dt represents the time interval of the ultrasonic echo transit time spectrum signal, and i represents the i-th peak.

6. An ultrasonic backscattering bone density detection device according to claim 5, characterized in that, The specific steps of the linear regression analysis are as follows: Calculate the correlation parameters of the peak number density and the spectral line area with the bone density information respectively based on the linear regression analysis algorithm. The correlation parameters include the correlation coefficient and the significance test value. When the significance test value is less than the preset threshold, determine the bone density information based on the correlation parameters at this time.

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