KR101002079B1 - Method of measuring blood vessel by blood vessel measurement apparatus - Google Patents

Abstract

PURPOSE: A method for measuring a blood vessel by a blood vessel measuring device is provided to simply diagnose a cardiovascular disease by measuring the intima-media thickness of a carotid artery in consideration of the change of space and time. CONSTITUTION: A still image of a blood vessel is obtained(1-1). A pixel about the still image of the blood vessel is corrected(1-2). An ROI(Region of Interest) of the blood vessel is determined in the still image of the blood vessel(1-3). The intima line and adventitia line of the blood vessel included in the region of interest are read(1-4). The intima-media thickness of the blood vessel is measured through the intima and adventitia lines(1-5).

Description

Blood vessel measurement method of a blood vessel measurement device {METHOD OF MEASURING BLOOD VESSEL BY BLOOD VESSEL MEASUREMENT APPARATUS}

The present invention relates to a method for measuring blood vessels of a blood vessel measuring device, and more particularly, to read the inner membrane line and outer membrane line of the blood vessel through a still image or a moving image of a blood vessel, such as a carotid artery, and the read each line. The present invention relates to a blood vessel measuring method of a blood vessel measuring apparatus for measuring the intima film thickness in consideration of temporal variability or correlation with a biosignal. In addition, the present invention is obtained by adding the ECG signal or carotid wave signal as temporal information with higher temporal resolution to the image signal including the structural and temporal information of the carotid artery, thereby improving the accuracy of the temporal information, and in the spatial measurement range The present invention relates to a vascular measurement method of an angiography apparatus for measuring the thickness and temporal variability (ie, time variability) of each of the medial intima thickness of the carotid artery and its variability and temporal measurement range.

Rapid aging and lifestyle changes are increasing the deaths from cardiovascular and cerebrovascular diseases. Myocardial infarction and cerebral infarction caused by blockage of blood vessels are representative of cardiovascular / cerebrovascular diseases, which can lead to a serious condition in which death or recovery is impossible unless the vessel is reopened within 6 hours after the onset. In particular, myocardial infarction is the main cause of 90% of sudden deaths within 1 hour of onset.

There is an angiography for early diagnosis of such a disease, but there is a problem that the risk is large as invasive and does not include information indicating arteriosclerosis but only a change in the vascular diameter. Intravascular ultrasonography is also available but is not suitable for early diagnosis. Computed tomography (CT) is the preferred method for acquiring the internal state of the human body as a visual image.However, the morphological imaging of blood vessels requires the injection of a separate contrast agent into the body and requires expensive examination costs. . Magnetic Resonance Imaging (MRI) has the disadvantage of high cost and long acquisition time.

Carotid artery (IMT) Intima-Media Thickness (IMT) to measure morphological abnormalities, and blood flow-dependent brachial artery dilatation (FMD: Flow-Mediated brachial) to measure vascular endothelial function. artery dilation, arterial stiffness, and measured by pulse wave velocity.

In 2000, the American Heart Association (AHA) recognized that carotid endometrial thickness was an independent factor for cardiovascular / cerebrovascular disease risk. Carotid endometrial thickness can provide additional valuable information.

In addition, the rupture of the carotid endometrium over time and the degree of calcification of the flakes rupture more easily in the early stages of flake formation, resulting in a clinical outcome in which a relatively mild stenosis is more likely to cause acute myocardial infarction than a severe stenosis. It is thought that this can be explained, but there is no research report on this. On the other hand, the non-invasive and easy to measure method can be used to measure the median thickness, variability and time variability of the carotid artery by using an ultrasound medical device.

In addition, the carotid endometrial thickness is measured at a specific point of time such as the R-peak point of the electrocardiogram provided in the carotid artery ultrasound image for the reliability and reproducibility of the measurement. Since the time resolution is greatly reduced, the R-peak point of the ECG in the image is not accurate.

The present invention has been made to improve the prior art as described above, the blood vessels corresponding to a specific time point of the biological signal after measuring the biological signal such as electrocardiogram signal and carotid artery wave signal with vascular ultrasound imaging of the carotid artery It is an object of the present invention to provide a vascular measurement method of a vascular measuring apparatus capable of measuring the endometrial thickness of blood vessels such as carotid arteries in consideration of the correlation with the bio-signal by measuring the endometrial thickness of the through the video.

In addition, an object of the present invention is to provide a method for measuring blood vessels of a blood vessel measuring apparatus capable of acquiring an ECG signal and a carotid wave signal having a relatively higher temporal information resolution in addition to the carotid artery ultrasound video, which is spatiotemporal information.

Another object of the present invention is to provide a measurement probe capable of measuring a carotid artery wave while acquiring a carotid video that is spatiotemporal information using an ultrasonic probe.

Another object of the present invention is to provide a blood vessel measuring method of a blood vessel measuring apparatus capable of obtaining an optimal selection region from a measurement target region of a carotid artery ultrasound image.

In addition, an object of the present invention is to provide a method for measuring blood vessels of an apparatus for measuring blood vessels that can utilize specific points of ECG and carotid waves such as accurate maximum and minimum expansion times of blood vessels for reliability and reproducibility of measurement.

In order to achieve the above object and to solve the problems of the prior art, the blood vessel measuring method of the blood vessel measuring apparatus according to an embodiment of the present invention, the step of obtaining a still image of the predetermined vessel (S1-1) ); Determining a region of interest (ROI) of the blood vessel in a still image of the blood vessel (S1-3); Reading the inner membrane line and the outer membrane line of the blood vessel included in the thickness measurement area (S1-4); And measuring the intima film thickness of the blood vessel through the inner film line and the outer film line (S1-5).

In addition, the blood vessel measuring method of the blood vessel measuring apparatus according to another embodiment of the present invention, the step (S2-1) to obtain a video photographing the blood vessel (predetermined); Selecting a first frame among one or more frames included in the video (S2-2); Determining a first region of interest (ROI) of the blood vessel in the first frame (S1-3); Reading the first inner membrane line and the first outer membrane line of the blood vessel included in the first thickness measuring region (S1-4); Reading an intima line and an intima line for each of the other frames of the video through the read first inner line and the first outer line of the first frame (S2-3); And measuring the intima film thickness of the blood vessel for each frame included in the video (S2-4).

In addition, the blood vessel measuring method of the blood vessel measuring apparatus according to another embodiment of the present invention, the step (S3-1) to obtain a video photographing the (predetermined) blood vessels; Acquiring a biosignal signal of the body photographing the blood vessel (S3-2); Selecting a specific viewpoint or section of the biosignal as a first viewpoint (S3-3); Selecting a first frame corresponding to a first time point of the bio signal from one or more frames included in the video (S3-4); Determining a first region of interest (ROI) of the blood vessel in the first frame (S1-3); Reading the first inner membrane line and the first outer membrane line of the blood vessel included in the first thickness measuring region (S1-4); And measuring a first intima film thickness of the blood vessel with respect to the first frame (S3-6).

In addition, the blood vessel measuring method of the blood vessel measuring apparatus according to another embodiment of the present invention, the step (S4-1) to obtain a video photographing a predetermined (predetermined) vessel; Acquiring a bio-signal of the body that photographed the blood vessel (S4-2); Selecting a first frame among one or more frames included in the video (S4-3); Determining a first region of interest (ROI) of the blood vessel in the first frame (S1-3); Reading the first inner membrane line and the first outer membrane line of the blood vessel included in the first thickness measuring region (S1-4); Reading an intima line and an intima line for each of the other frames of the video through the read first inner line and the first outer line of the first frame (S2-3); Generating an inner film time line and an outer film time line for the video by interpolating the inner film line and the outer film line of each frame included in the video on a time axis (S3-5); And measuring the first intima film thickness of the blood vessel corresponding to the first time point of the biosignal through the inner film time line and the outer film time line (S2-4).

According to the blood vessel measuring device and the blood vessel measuring method of the present invention, by measuring the median medial thickness of the carotid artery using spatial or temporal variability, it is possible to examine and evaluate the degree of cardiovascular disease more easily and safely at a minimum cost. The effect can be obtained.

In addition, according to the blood vessel measuring device and the blood vessel measuring method of the present invention, it is possible to obtain the effect of improving the temporal resolution without newly configuring the ultrasonic probe.

In addition, according to the blood vessel measuring device and the blood vessel measuring method of the present invention, by measuring the intima-media thickness of blood vessels, such as carotid arteries at a desired time point or section through an electrocardiogram signal or carotid wave signal, by considering the correlation with the biological signal, The effect of improving the reliability and reproducibility of blood vessel measurement can be obtained.

In addition, according to the blood vessel measuring apparatus and the blood vessel measuring method of the present invention, by measuring the information on the blood vessels, such as carotid arteries in consideration of the correlation with the biological signal through the ultrasound video and considering the spatial and temporal variability of the vascular measurement, respectively, Advances in medicine and easier and simpler examinations can provide the benefits of patient convenience.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a block diagram of an entire system for a blood vessel measuring apparatus using ultrasonic waves according to an embodiment of the present invention.

The present invention will be described based on the measurement of endometrial thickness and variability and time variability of the carotid artery using the carotid artery using ultrasound, but the present invention is not limited thereto. That is, the present invention includes an apparatus and method for measuring the median film thickness, the variability and the time variability of the carotid artery by using a carotid artery image obtained by using a device other than ultrasound. Also included are devices and methods for measuring in-film thickness and variability and time variability.

The blood vessel measuring method of the blood vessel measuring apparatus according to an embodiment of the present invention can measure the intima film thickness, spatial variability, and temporal variability of various blood vessels existing in the human body. However, in the present specification, for convenience of description, the blood vessel measuring apparatus will be described by taking an example of measuring the medial film thickness, spatial variability, and temporal variability of the carotid artery.

In addition, the blood vessel measuring apparatus according to the embodiment of the present invention as shown in FIG. 1 may include an ultrasound probe, an ultrasonic medical device, a computing device, a carotid wave sensor, an electrocardiogram sensor, and a carotid image acquisition device.

The ultrasound medical apparatus measures a carotid artery image signal by using the ultrasound probe. The carotid artery of a person may be measured for 1 to 10 seconds using the ultrasonic probe. The ultrasound medical apparatus includes an NTSC output port, and the measured ultrasound carotid artery image signal may output a carotid ultrasound image signal through the NTSC output port. The output video signal may be input to the computing device through a LAN cable.

The computing device converts the analog image signal generated by the ultrasound medical device into a digital image signal, and analyzes and processes the digital image signal to generate information measuring the median film thickness, the variability, and the time variability of the carotid artery. can do. When the digital image signal is analyzed and processed on the time axis, the analysis and processing may be performed using only a carotid artery ultrasound image signal measured for 1 to 10 seconds.

In addition, when analyzing and processing the digital video signal on the time axis, an ECG signal measured by an ECG sensor may be used. The ECG signal may be input to the computing device via an ECG signal cable. The sampling frequency of the ECG signal can be varied from 200 Hz to 2 kHz.

In addition, when analyzing and processing the digital image signal on the time axis, the carotid artery wave signal measured by the ultrasonic probe may be used. The carotid wave signal may be measured through a carotid wave sensor attached to the ultrasonic probe. The carotid wave signal may be input to the computing device via a carotid wave signal cable. The sampling frequency of the carotid artery wave signal is also variable from 200 Hz to 2 kHz.

One or more pressure sensors may be attached to the ultrasonic probe to measure the carotid wave signal through the pressure sensor. Each pressure sensor may be connected to an ultrasonic probe cable to transmit the measured carotid artery wave signal to the ultrasound medical apparatus or the computing device.

Figure 2 is an internal configuration of the carotid artery intima membrane measuring apparatus using the ultrasound according to an embodiment of the present invention.

Carotid endocardium measuring device includes a video signal circuit, an electrocardiogram measuring circuit, an electrocardiogram signal amplifier circuit, a carotid wave measurement circuit, a carotid wave signal amplifier circuit, a video processor, an analog-digital converter (ADC), a main processor, RAM, ROM, and LAN. Each circuit includes a filter circuit.

As shown in FIG. 2, the video signal circuit receives and filters a plurality of carotid image signals measured by an ultrasound medical apparatus. The ECG amplifier circuit filters and amplifies the ECG signal measured by the ECG measurement circuit. The carotid wave signal amplification circuit filters and amplifies the carotid wave signal through the carotid wave measuring circuit. The apparatus for measuring the carotid endocardium includes at least one of the electrocardiogram signal related circuit and the carotid wave signal related circuit. The ECG signal and / or carotid wave signal are digitized through a filter and amplification circuit at a sampling frequency of 200 Hz to 2 kHz.

The carotid endocardium measuring apparatus according to the present invention may include a video processor for digitizing the NTSC signal, and may include at least one RAM for each operation.

The ROM stores a program for driving the carotid endometrium measurement device. A field-programmable gate array (FPGA) is a programmable logic chip that is manipulated through a control switch. The LAN transmits the information generated by the carotid endometrial medulla measuring apparatus according to the present invention to a computer.

3 is a block diagram of an ultrasonic probe according to an embodiment of the present invention.

At least one pressure sensor is attached to the ultrasonic probe, and the carotid artery wave signal may be measured using the pressure sensor. Each pressure sensor is connected to an ultrasonic probe cable to transmit the measured carotid artery wave signal to the carotid artery analysis computer through the carotid artery image acquisition device, rather than to the ultrasound medical device.

In order to measure the endometrial thickness and variability of the carotid artery by time-varying, the present invention provides a cardiac artery over 10 mm in the cardiac direction from a point about 10 mm away from the cardiac direction at the point where the carotid artery bulge and the total carotid artery are in contact (branch). Carotid artery images in the region can be precisely measured at regular time intervals for about 1 to 10 seconds using an ultrasound medical device. In the measurement, not only a still image at a specific point in time but also a video of about 1 second to 10 seconds may be obtained. Conventionally, the carotid artery was measured only with a still image, but in the present invention, the carotid artery may be measured. When measured for 10 seconds, a still image of 300 still images can be obtained at 30 still images / s × 10s. Hereinafter, the video measured for 1 second will be described as an example.

4 is a diagram illustrating a method of correcting a pixel size in a carotid artery image measured using an ultrasound medical apparatus, according to an exemplary embodiment.

First, pixel size correction is necessary before measuring the carotid artery. When the carotid artery is measured by an ultrasonic medical device, a dot may be taken every 10 mm on the right side as shown in FIG. 4. By repeating the 10 mm calibration point at least three times, one pixel size can be calculated by determining the number of pixels in the 10 mm interval. At this time, the average and standard deviation can be obtained and the standard deviation can be measured again if the standard deviation is 5% or more of the average. This can be done to enable measurements of median medial thickness, variability and time variability of the carotid artery, as well as sub- or enlarged images of 40 mm depth images.

5 is a flow chart showing the flow of the blood vessel measuring method according to the first embodiment of the present invention.

The blood vessel measuring method of the blood vessel measuring apparatus according to the first embodiment of the present invention may be implemented through an ultrasound still image taken of a carotid artery. According to a first embodiment of the present invention, the blood vessel measuring device obtains a still image of a predetermined blood vessel. The blood vessel measuring apparatus determines a region of interest (ROI) of the blood vessel in a still image of the blood vessel. The blood vessel measuring device reads the inner membrane line and outer membrane line of the blood vessel included in the thickness measuring region. The blood vessel measuring device measures the intima film thickness of the blood vessel through the inner membrane line and the outer membrane line.

The blood vessel is a carotid artery, and the still image of the blood vessel may be implemented as an ultrasonic still image of the blood vessel. The blood vessel measuring apparatus may correct the pixel size of the still image of the blood vessel as described with reference to FIG. 4.

The blood vessel measuring device requests a user to select the thickness measuring region, secures an area to which the reference point of the thickness measuring region selected by the user moves up, down, left and right, and includes the still image of the blood vessel through the movement of the reference point. The thickness measurement region may be determined so that the boundary between blood and tissue is located at the center.

The blood vessel measuring device calculates any one or more of the average, standard deviation, skewness, kurtosis, uniformity, and entropy of the thickness measurement area while moving the reference point, and when the calculation result is greater than or equal to a selected threshold, the blood And calculating a maximum value of the correlation coefficient to allow the boundary of the tissue to be located at the center, and determine the thickness measurement area through the maximum value of the correlation coefficient.

The apparatus for measuring blood vessels may acquire respective boundary points of the inner and outer membranes of the blood vessel through the differential change amount of the blood vessel still image, and connect the respective boundary points to generate the inner membrane line and the outer membrane line of the blood vessel. When at least one of the boundary points of the inner and outer membranes of the blood vessel does not exist at a predetermined position, the blood vessel measuring apparatus may obtain the respective boundary points by deleting other boundary points of the position or interpolating boundary points of another position. Can be.

The vascular measuring apparatus may measure the endometrial thickness through the number of pixels and the unit pixel size of the vascular still image positioned between the inner membrane line and the outer membrane line.

Referring to Figure 5, the blood vessel measuring device reads the ultrasound carotid artery still image (step 1-1). The apparatus for measuring blood vessels performs pixel calibration on the still image (steps 1-2), and selects a thickness measuring area (hereinafter referred to as "ROI") (steps 1-3). The blood vessel measuring device detects the carotid intima and outer membrane lines in the ROI (steps 1-4), and measures the carotid intima thickness and variability using the detected lines (steps 1-5). As variability, standard deviation, variance, etc. can be calculated. A detailed method of measuring the thickness and the variability will be described later with reference to FIG. 12.

6 is a flow chart showing the flow of the blood vessel measuring method according to a second embodiment of the present invention.

The blood vessel measuring method of the blood vessel measuring apparatus according to the second embodiment of the present invention may be implemented through an ultrasound image photographed against the carotid artery. According to a second embodiment of the present invention, the blood vessel measuring device obtains a video photographing a predetermined blood vessel, selects a first frame among one or more frames included in the video, and in the first frame The first thickness measuring region (ROI) of the blood vessel is determined, and the first inner membrane line and the first outer membrane line of the vessel included in the first thickness measuring region are read, and the read first After reading the intima line and outer membrane line for each of the other frames of the video through the first intima line and the first outer membrane line of the frame, measuring the intima film thickness of the blood vessel for each frame included in the video. do.

The blood vessel is a carotid artery, and the still image of the blood vessel may be implemented as an ultrasonic still image of the blood vessel. The blood vessel measuring apparatus may correct the pixel size of the still image of the blood vessel as described with reference to FIG. 4.

The blood vessel measuring device requests a user to select the thickness measuring region, secures an area to which the reference point of the thickness measuring region selected by the user moves up, down, left and right, and includes the still image of the blood vessel through the movement of the reference point. The thickness measurement region may be determined so that the boundary between blood and tissue is located at the center.

The blood vessel measuring device calculates any one or more of the average, standard deviation, skewness, kurtosis, uniformity, and entropy of the thickness measurement area while moving the reference point, and when the calculation result is greater than or equal to a selected threshold, the blood And calculating a maximum value of the correlation coefficient to allow the boundary of the tissue to be located at the center, and determine the thickness measurement area through the maximum value of the correlation coefficient.

The apparatus for measuring blood vessels may obtain respective boundary points of the inner and outer membranes of the blood vessel through the differential change amount of the blood vessel still image, and connect the respective boundary points to generate the inner membrane line and the outer membrane line of the blood vessel. When at least one of the boundary points of the inner and outer membranes of the blood vessel does not exist at a predetermined position, the blood vessel measuring apparatus may obtain the respective boundary points by deleting other boundary points of the position or interpolating boundary points of another position. Can be.

The vascular measuring apparatus may measure the endometrial thickness through the number of pixels and the unit pixel size of the vascular still image positioned between the inner membrane line and the outer membrane line.

The blood vessel measuring device connects each point of the inner film line and each point of the outer film line of each frame included in the video to each other on the time axis to generate the inner film time line and the outer film time line, and the inner film time line and The time variability of the inner film thickness may be measured through the outer film time line.

Referring to FIG. 6, the blood vessel measuring apparatus first reads an ultrasound carotid video (step 2-1) and selects a still image from the video (step 2-2). Then, steps 1-2 to 1-4 (hereinafter referred to as "1-6" steps) shown in FIG. 5 are performed (steps 1-6). That is, the pixel calibration of the selected still image may be performed, the ROI may be selected, and the carotid artery membrane and the outer membrane line may be detected.

The blood vessel measuring apparatus detects each of the inner and outer membrane lines of the remaining left and right still images based on the detected lines (steps 2-3). The vascular measuring apparatus measures carotid intima media thickness and variability of each still image using the inner and outer membrane lines detected for each still image (steps 2-4), and detects lines and variability of each still image. Is connected to the time axis to measure the variability of the intima film thickness and the variability (steps 2-5). Dispersion may be used to obtain the variability of the thickness used for the time variability measurement.

7 is a flow chart showing the flow of the blood vessel measuring method according to a third embodiment of the present invention.

The blood vessel measuring method of the blood vessel measuring apparatus according to the third embodiment of the present invention may be implemented through a biosignal measured together with an ultrasound image photographed against the carotid artery.

According to a third embodiment of the present invention, the blood vessel measuring apparatus obtains a moving image of a predetermined blood vessel and acquires a raw signal of the body of the blood vessel. The blood vessel measuring apparatus selects a first frame corresponding to a first time point of the bio signal from one or more frames included in the video, and a first thickness measuring region (ROI) of the blood vessel in the first frame. Is determined. The blood vessel measuring apparatus reads the first inner membrane line and the first outer membrane line of the blood vessel included in the first thickness measuring region, and measures the first intima thickness of the blood vessel with respect to the first frame.

The blood vessel measuring apparatus reads the inner membrane line and the outer membrane line for each of the other frames of the moving image through the first inner membrane line and the first outer membrane line of the read first frame, and each frame included in the moving image. Interstitial line and outer line of the interpolation line are interpolated on a time axis to generate an inner time line and an outer time line for the video, and the inner time line and the outer time line correspond to the first time point of the bio-signal through the inner time line. Any one or more of the first inner median thickness of blood vessels can be measured.

The blood vessel is a carotid artery, and the still image of the blood vessel may be implemented as an ultrasonic still image of the blood vessel. The blood vessel measuring apparatus may correct the pixel size of the still image of the blood vessel as described with reference to FIG. 4.

The blood vessel measuring device requests a user to select the thickness measuring region, secures an area to which the reference point of the thickness measuring region selected by the user moves up, down, left and right, and includes the still image of the blood vessel through the movement of the reference point. The thickness measurement region may be determined so that the boundary between blood and tissue is located at the center.

The blood vessel measuring device calculates any one or more of the average, standard deviation, skewness, kurtosis, uniformity, and entropy of the thickness measurement area while moving the reference point, and when the calculation result is greater than or equal to a selected threshold, the blood And calculating a maximum value of the correlation coefficient to allow the boundary of the tissue to be located at the center, and determine the thickness measurement area through the maximum value of the correlation coefficient.

The apparatus for measuring blood vessels may acquire respective boundary points of the inner and outer membranes of the blood vessel through the differential change amount of the blood vessel still image, and connect the respective boundary points to generate the inner membrane line and the outer membrane line of the blood vessel. When at least one of the boundary points of the inner and outer membranes of the blood vessel does not exist at a predetermined position, the blood vessel measuring apparatus may obtain the respective boundary points by deleting other boundary points of the position or interpolating boundary points of another position. Can be.

The vascular measuring apparatus may measure the endometrial thickness through the number of pixels and the unit pixel size of the vascular still image positioned between the inner membrane line and the outer membrane line.

In addition, the biosignal is an electrocardiogram signal, and the first time point of the biosignal may be implemented as any one of a P-peak point, an R-peak point, and a T-peak point of the ECG signal. have. In addition, the biosignal is a carotid artery wave signal, and the first time point of the biosignal signal is a PS-peak point, a PS-PP section midpoint, a PP-peak point, and PT of the carotid wave signal. It may be implemented at any one of the peak points.

Referring to FIG. 7, the blood vessel measuring apparatus reads an ultrasound carotid video (step 3-1), selects a biosignal (step 3-2), and selects a specific time point (or a specific section) of the selected biosignal ( Steps 3-3). An electrocardiogram signal or a carotid artery wave signal may be used as the biosignal. The blood vessel measuring apparatus selects a still image including the specific time point from the video (steps 3-4), and steps 1-6 and 2-3 (hereinafter, referred to as "steps 2-6") shown in FIG. (Steps 2-6). That is, the blood vessel measuring device performs pixel calibration on the selected still image, selects an ROI, detects carotid intima and outer membrane lines, and each of the inner and outer membrane lines of the remaining still images based on the detected lines. Can be detected. The vessel measuring device connects the detected lines through interpolation on the time axis (step 3-5), and measures carotid intima thickness and variability at a specific time point (or a specific section) selected in step 3-3. You can do it (steps 3-6).

8 is a flow chart showing the flow of the blood vessel measuring method according to a fourth embodiment of the present invention.

The blood vessel measuring method of the blood vessel measuring apparatus according to the fourth embodiment of the present invention may be implemented through a biosignal measured together with an ultrasound image photographed against the carotid artery.

According to the fourth embodiment of the present invention, the blood vessel measuring apparatus acquires a video photographing a predetermined blood vessel and selects a first frame among one or more frames included in the video. The blood vessel measuring device determines a first region of interest (ROI) of the blood vessel in the first frame, and the first inner membrane line and the first outer membrane line of the vessel included in the first thickness measuring region. Read it.

The blood vessel measuring apparatus reads the inner membrane line and the outer membrane line for each of the other frames of the moving image through the first inner membrane line and the first outer membrane line of the read first frame, and each frame included in the moving image. The inner film line and the outer film line of are interpolated on a time axis to generate an inner film time line and an outer film time line for the video.

The apparatus for measuring blood vessels acquires a biosignal of a body in which the blood vessel is photographed, and the first endometrial thickness of the blood vessel corresponding to the first time point of the biosignal through the inner membrane timeline and the outer membrane timeline. Measure

The blood vessel is a carotid artery, and the video of the blood vessel may be implemented as an ultrasound video of the blood vessel. In addition, the biosignal is an electrocardiogram signal, and the first time point of the biosignal may be implemented as any one of a P-peak point, an R-peak point, and a T-peak point of the ECG signal. have. In addition, the biosignal is a carotid artery wave signal, and the first time point of the biosignal signal is a PS-peak point, a PS-PP section midpoint, a PP-peak point, and PT of the carotid wave signal. It may be implemented at any one of the peak points.

Referring to FIG. 8, the blood vessel measuring apparatus reads an ultrasound carotid video (step 4-1), selects a bio signal (step 4-2), and selects a still image from the video (step 4-3). ). The blood vessel measuring apparatus performs steps 2-6 and 3-5 (hereinafter, referred to as “3-7 steps”) shown in FIG. 7. That is, the blood vessel measuring device performs pixel correction on the selected still image, selects an ROI, detects carotid intima and outer membrane lines, and each of the inner and outer membrane lines of the remaining still images based on the detected lines. Is detected and the detected lines are connected through interpolation on the time axis.

The vascular measuring apparatus measures carotid endometrial thickness and variability of each still image (steps 2-4), and analyzes variability of endometrial thickness and variability by connecting lines for each still image with a time axis. (Steps 2-5).

The final ROI is shown in FIG. 9. As shown in FIG. 9, the optimal ROI is preferably selected such that the boundary between blood and tissue is centered in the measurement area.

FIG. 10 is a diagram illustrating a specific method of measuring inner-film thickness and variability according to an embodiment of the present invention.

Referring to FIG. 10, the lines detected in the ROI are separated by the vertical axis, and the number of pixels between the inner film start point i and the outer film start point i is counted and multiplied by one pixel size obtained during the pixel calibration operation. Calculate Where n is the detected number. The inner film thickness is measured by averaging from the obtained inner films. In addition, the variability is also measured by expressing n detected thicknesses in one dimension. If the vessel is a morphologically curved vessel, each point i is calculated as a normal rather than as shown above. In the same manner as described above, steps 1-5 shown in FIG. 5 may be performed.

The method illustrated in FIG. 6 is a method of enabling temporal analysis by applying the method illustrated in FIG. 5 to a video. By drawing the median thickness obtained from each still image over time, the variation can be analyzed. Time domain, frequency domain, and nonlinear analyzes can be used to analyze the thickness variation of each film. Typical examples include standard deviation, variance, and fast fourier transform (FFT). For more detailed analysis, you can also interpolate and use resampling.

11 is a diagram illustrating a method of connecting the carotid intima and outer membrane lines in the time axis according to an embodiment of the present invention.

Referring to FIG. 11, the intima and outer membranous lines are diagrammatically plotted into several points, such as a still image (n) ROI. When the i-th intima start point is interpolated with the i-th intima points in the left and right still images (n-1) and the still image (n + 1), a signal called intima start point interpolation (i) can be obtained. As described above, the envelope starting point interpolation (i) can be obtained from the envelope. The signals thus obtained are calculated from 1 to i (in one embodiment, 128 of the number of x-axis pixels of the ROI) to obtain interpolated inner film start line and outer film start line.

The intima start line and the outer start line in each of the detected still images may form a line on the time axis. Lines on the time axis account for carotid intima thickness and variability and time variability. The line on the time axis can be generated using an interpolation method. The interpolation of the intima and outer membrane lines in each still image using interpolation on the time axis is to measure the endometrial thickness and variability of the carotid artery at that point when using a specific time point of the biosignal.

FIG. 12 illustrates a specific time point that can be selected using an ECG signal or a carotid wave signal according to an embodiment of the present invention.

Referring to FIG. 12, in the present invention, an ultrasound carotid artery image and a biosignal may be simultaneously obtained. The biosignal includes an electrocardiogram signal and / or a carotid wave signal. In the case of using the ECG signal, the P-peak point, the R-peak point, or the T-peak point may be selected as a specific time point to obtain a carotid artery image.

When the carotid artery wave signal is used, the PS-peak point, the PS-PP section midpoint, the PP-peak point, the PT-peak point, or the PT-PS section point may be selected as a specific time point to obtain a carotid artery image.

When a specific time point is selected, the carotid artery video including the specific time point is selected. According to the NTSC standard, 30 still image signals are acquired in one second.

When the R-peak point is selected as a specific time point, the still image 13 including the same is selected. When the PP-peak point is selected as the specific time point, the still image 18 including the same is selected. The intima and outer membrane lines may be detected using the selected still image, and the inner and outer membrane lines for the remaining still images may be detected based on the selected still image.

FIG. 13 illustrates a method of obtaining an ultrasound carotid artery image at a specific time point through time-axis interpolation according to an embodiment of the present invention.

Referring to FIG. 13, an image including a specific point in time (eg, an R-peak point of an ECG signal or a PP-peak point of a carotid wave signal) may be more detailed.

That is, one still image, for example, the still image n, includes sampling points of six electrocardiogram signals or carotid wave signals. Therefore, since the sampling time point of any of the six samples corresponds to the R-peak point or the PP-peak point, the still image n cannot be regarded as representing an image at the correct R-peak point or the PP-peak point. . Therefore, as shown in FIG. 13, an image at an accurate R-peak point or a PP-peak point can be estimated through interpolation (e.g., cubic spline interpolation) on the time axis, and an accurate R-peak is obtained from the image. Carotid intima thickness and variability at points or PP-peak points can be measured.

The blood vessel measuring method according to the present invention may be embodied in the form of program instructions that can be executed by various computer means and recorded in a computer readable medium. The computer readable medium may include program instructions, data files, data structures, etc. alone or in combination. Program instructions recorded on the media may be those specially designed and constructed for the present invention, or they may be of the kind well-known and available to those in charge of computer software. Examples of computer-readable recording media include magnetic media such as hard disks, floppy disks, and magnetic tape, optical media such as CD-ROMs, DVDs, and magnetic disks, such as floppy disks. Magneto-optical media, and hardware devices specifically configured to store and execute program instructions, such as ROM, RAM, flash memory, and the like. The medium may be a transmission medium such as an optical or metal line, a wave guide, or the like, including a carrier wave for transmitting a signal designating a program command, a data structure, or the like. Examples of program instructions include not only machine code generated by a compiler, but also high-level language code that can be executed by a computer using an interpreter or the like. The hardware device described above may be configured to operate as one or more software modules to perform the operations of the present invention, and vice versa.

As described above, the present invention has been described by way of limited embodiments and drawings, but the present invention is not limited to the above-described embodiments, which can be variously modified and modified by those skilled in the art to which the present invention pertains. Modifications are possible. Accordingly, the spirit of the present invention should be understood only by the claims set forth below, and all equivalent or equivalent modifications thereof will belong to the scope of the present invention.

1 is a block diagram of an entire system including a device for measuring the median thickness of the carotid artery using ultrasound according to an embodiment of the present invention.

Figure 2 is an internal configuration of the device for measuring the median thickness of the carotid artery using ultrasound according to an embodiment of the present invention.

3 is a view showing the structure of an ultrasonic probe according to an embodiment of the present invention.

4 is a diagram illustrating a method of correcting a pixel size in a carotid artery image measured using an ultrasound medical apparatus, according to an embodiment of the present invention.

Figure 5 is a flow chart showing the flow of the blood vessel measuring method according to a first embodiment of the present invention.

Figure 6 is a flow chart showing the flow of the blood vessel measuring method according to a second embodiment of the present invention

7 is a flow chart showing the flow of the blood vessel measuring method according to a third embodiment of the present invention.

8 is a flow chart showing the flow of the blood vessel measuring method according to a fourth embodiment of the present invention.

9 is a view showing a finally determined thickness measurement area in accordance with an embodiment of the present invention.

10 is a view showing a specific method for measuring the inner film thickness and the variability according to an embodiment of the present invention.

11 is a view showing a method of connecting the carotid intima and outer membrane lines in the time axis according to an embodiment of the present invention.

12 is a diagram illustrating a specific time point that can be selected using an electrocardiogram signal or a carotid wave signal according to an embodiment of the present invention.

FIG. 13 illustrates a method of obtaining an ultrasound carotid artery image at a specific time point through time-axis interpolation according to an embodiment of the present invention. FIG.

<Description of the symbols for the main parts of the drawings>

Step 1-1: Carotid Artery Ultrasound Still Image Reading

Step 1-2: Pixel Calibration

Step 1-3: Select Thickness Measurement Area

Step 1-4: Detect inner line and outer line

Steps 1-5: Measuring Intima Thickness and Variability

Claims (32)

delete delete delete delete Obtaining a still image of a predetermined blood vessel (S1-1); Determining a region of interest (ROI) of the blood vessel in a still image of the blood vessel (S1-3); Reading the inner membrane line and the outer membrane line of the blood vessel included in the thickness measurement area (S1-4); And Measuring the intima film thickness of the blood vessel through the inner film line and the outer film line (S1-5) Including, Determining a region of interest (ROI) of the vessel in the still image of the vessel (S1-3), Requesting a user to select the thickness measurement area; Securing an area to which the reference point of the thickness measurement area selected by the user moves up, down, left, and right; And Determining the thickness measurement area such that a boundary between blood and tissue included in the still image of the blood vessel is located at the center by moving the reference point Including; Determining the thickness measurement area so that the boundary of blood and tissue included in the still image of the blood vessel is located in the center through the movement of the reference point, Calculating at least one of an average, standard deviation, skewness, kurtosis, uniformity, and entropy of the thickness measurement region while moving the reference point; And Calculating a maximum value of a correlation coefficient such that a boundary between the blood and the tissue is located at the center when the calculation result is greater than or equal to a predetermined threshold; Determining the thickness measurement region based on the maximum value of the correlation coefficient A blood vessel measuring method of a blood vessel measuring apparatus comprising a. The method of claim 5, Reading the inner membrane line and outer membrane line of the blood vessel included in the thickness measurement area (S1-4), Acquiring respective boundary points of the inner and outer membranes of the blood vessel through the differential change amount of the blood vessel still image; And Connecting the boundary points to generate the inner line and the outer line of the blood vessel; A blood vessel measuring method of a blood vessel measuring apparatus comprising a. The method of claim 6, Acquiring the respective boundary points for the inner and outer membranes of the blood vessel through the differential change amount of the vascular still image, If at least one of the boundary points of the inner and outer membranes of the blood vessel is not present at a predetermined position, removing the other boundary points of the position or interpolating the boundary points of the other position to obtain the respective boundary points A blood vessel measuring method of a blood vessel measuring apparatus comprising a. The method of claim 5, Measuring the intima film thickness of the blood vessel through the inner film line and the outer film line (S1-5), Measuring the endometrial thickness through the pixel number and unit pixel size of the vascular still image located between the endocardium line and the outer membrane line A blood vessel measuring method of a blood vessel measuring apparatus comprising a. delete delete delete delete Acquiring a video of the predetermined blood vessel (S2-1); Selecting a first frame among one or more frames included in the video (S2-2); Determining a first region of interest (ROI) of the blood vessel in the first frame (S1-3); Reading the first inner membrane line and the first outer membrane line of the blood vessel included in the first thickness measuring region (S1-4); Reading an intima line and an intima line for each of the other frames of the video through the read first inner line and the first outer line of the first frame (S2-3); And Measuring the intima film thickness of the blood vessel for each frame included in the video (S2-4) Including, Determining a region of interest (ROI) of the blood vessel in the first frame (S1-3), Requesting a user to select the thickness measurement area for the first frame; Securing an area to which the reference point of the thickness measurement area selected by the user moves up, down, left, and right; And Determining the thickness measurement area such that a boundary between blood and tissue included in the first frame is located at the center by moving the reference point Including; Determining the thickness measurement area so that the boundary between the blood and tissue included in the first frame is located in the center through the movement of the reference point, Calculating at least one of an average, standard deviation, skewness, kurtosis, uniformity, and entropy of the thickness measurement region while moving the reference point; And Calculating a maximum value of a correlation coefficient such that a boundary between the blood and the tissue is located at the center when the calculation result is greater than or equal to a predetermined threshold; Determining the thickness measurement region based on the maximum value of the correlation coefficient A blood vessel measuring method of a blood vessel measuring apparatus comprising a. The method of claim 13, The inner film time line and the outer film time line are generated by connecting the respective points of the inner film line and the outer film line of each frame included in the video on the time axis corresponding to each other. Measuring the time variability of the inner film thickness through the (S2-5) A blood vessel measuring method of a blood vessel measuring apparatus further comprising a. The method of claim 13, In operation S1-4, the first inner membrane line and the first outer membrane line of the blood vessel included in the first thickness measurement region are read. Obtaining respective boundary points of the inner and outer membranes of the blood vessel through the differential change amount of the first frame; And Connecting the boundary points to generate the inner line and the outer line of the blood vessel; A blood vessel measuring method of a blood vessel measuring apparatus comprising a. The method of claim 15, Acquiring respective boundary points for the inner and outer membranes of the blood vessel through the differential change amount of the first frame, If at least one of the boundary points of the inner and outer membranes of the blood vessel is not present at a predetermined position, removing the other boundary points of the position or interpolating the boundary points of the other position to obtain the respective boundary points A blood vessel measuring method of a blood vessel measuring apparatus comprising a. Acquiring a moving picture of a predetermined blood vessel (S3-1); Acquiring a biosignal signal of the body photographing the blood vessel (S3-2); Selecting a specific viewpoint or section of the biosignal as a first viewpoint (S3-3); Selecting a first frame corresponding to a first time point of the bio signal from one or more frames included in the video (S3-4); Determining a first region of interest (ROI) of the blood vessel in the first frame (S1-3); Reading the first inner membrane line and the first outer membrane line of the blood vessel included in the first thickness measuring region (S1-4); And Measuring the first intima film thickness of the blood vessel with respect to the first frame (S3-6) A blood vessel measuring method of a blood vessel measuring apparatus comprising a. The method of claim 17, Reading an intima line and an intima line for each of the other frames of the video through the read first inner line and the first outer line of the first frame (S2-3); And Generating an inner film time line and an outer film time line for the video by interpolating the inner film line and the outer film line of each frame included in the video on a time axis (S3-5); Contains more Measuring the first intima film thickness of the blood vessel with respect to the first frame (S3-6) is the blood vessel of the blood vessel corresponding to the first time point of the biological signal through the inner film time line and the outer film time line A blood vessel measuring method of a blood vessel measuring device, characterized in that the first inner film thickness is measured. The method of claim 17, The blood vessel is a carotid artery, and the video of the blood vessel is a blood vessel measuring method of the blood vessel measuring apparatus, characterized in that the ultrasonic video taken by the blood vessel. The method of claim 17, Correcting a pixel size of each frame included in the blood vessel video (S1-2) A blood vessel measuring method of a blood vessel measuring apparatus further comprising a. The method of claim 17, Determining a region of interest (ROI) of the blood vessel in the first frame (S1-3), Requesting a user to select the thickness measurement area for the first frame; Securing an area to which the reference point of the thickness measurement area selected by the user moves up, down, left, and right; And Determining the thickness measurement area such that a boundary between blood and tissue included in the first frame is located at the center by moving the reference point A blood vessel measuring method of a blood vessel measuring apparatus comprising a. The method of claim 21, Determining the thickness measurement area so that the boundary of blood and tissue included in the first frame is located in the center through the movement of the reference point, Calculating at least one of an average, standard deviation, skewness, kurtosis, uniformity, and entropy of the thickness measurement region while moving the reference point; And Calculating a maximum value of a correlation coefficient such that a boundary between the blood and the tissue is located at the center when the calculation result is greater than or equal to a predetermined threshold; Determining the thickness measurement region based on the maximum value of the correlation coefficient A blood vessel measuring method of a blood vessel measuring apparatus comprising a. The method of claim 17, Reading the first inner membrane line and the first outer membrane line of the blood vessel included in the first thickness measurement region (S1-4), Obtaining respective boundary points of the inner and outer membranes of the blood vessel through the differential change amount of the first frame; And Connecting the boundary points to generate the inner line and the outer line of the blood vessel; A blood vessel measuring method of a blood vessel measuring apparatus comprising a. 24. The method of claim 23, Acquiring respective boundary points for the inner and outer membranes of the blood vessel through the differential change amount of the first frame, If at least one of the boundary points of the inner and outer membranes of the blood vessel is not present at a predetermined position, removing the other boundary points of the position or interpolating the boundary points of the other position to obtain the respective boundary points A blood vessel measuring method of a blood vessel measuring apparatus comprising a. The method of claim 17, The biosignal is an electrocardiogram signal, and the first time point of the biosignal is any one of a P-peak point, an R-peak point, and a T-peak point of the ECG signal. . The method of claim 17, The biosignal is a carotid artery wave signal, and the first time point of the biosignal signal is any one of a PS-peak point, a PS-PP section intermediate point, a PP-peak point, and a PT-peak point of the carotid artery wave signal. A blood vessel measuring method of a blood vessel measuring apparatus. Acquiring a video of the predetermined blood vessel (S4-1); Acquiring a bio-signal of the body that photographed the blood vessel (S4-2); Selecting a first frame among one or more frames included in the video (S4-3); Determining a first region of interest (ROI) of the blood vessel in the first frame (S1-3); Reading the first inner membrane line and the first outer membrane line of the blood vessel included in the first thickness measuring region (S1-4); Reading an intima line and an intima line for each of the other frames of the video through the read first inner line and the first outer line of the first frame (S2-3); Generating an inner film time line and an outer film time line for the video by interpolating the inner film line and the outer film line of each frame included in the video on a time axis (S3-5); And Measuring the first intima film thickness of the blood vessel corresponding to the first time point of the biosignal through the intima time line and the outer film time line (S2-4) A blood vessel measuring method of a blood vessel measuring apparatus comprising a. The method of claim 27, The blood vessel is a carotid artery (carotid artery), the video of the blood vessel is a blood vessel measuring method of the blood vessel measuring device, characterized in that the ultrasonic video taken by the ultrasound. The method of claim 27, The biosignal is an electrocardiogram signal, and the first time point of the biosignal is any one of a P-peak point, an R-peak point, and a T-peak point of the ECG signal. Way. The method of claim 27, The biosignal is a carotid artery wave signal, and the first time point of the biosignal signal is any one of a PS-peak point, a PS-PP section midpoint, a PP-peak point, and a PT-peak point of the carotid artery wave signal. A blood vessel measuring method of a blood vessel measuring apparatus, characterized in that. The method of claim 27, Measuring time variability of the inner film thickness through the inner film time line and the outer film time line (S2-5); A blood vessel measuring method of a blood vessel measuring apparatus further comprising a. delete

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