TWI809601B - Vascular state measuring device and method - Google Patents

Abstract

A vascular state measuring device comprises a coil set, a signal source and a processing module. The coil set is configured to output a first electromagnetic signal to a target area to generate an eddy current in the target area, and receive a second electromagnetic signal induced by the eddy current. The signal source is coupled to the coil set and configured to output an AC signal to the coil set to generate the first electromagnetic signal. The processing module is coupled to the coil set and configured to compute a feature signal based on the first electromagnetic signal and the second electromagnetic signal. Wherein the feature signal is related to at least one status of at least one vessel located at the target area.

Description

Device and method for measuring blood vessel state

The present invention relates to a blood vessel state measurement device and method; in particular, it relates to a magnetoelectric effect non-invasive blood vessel state measurement device and method.

The measurement of vascular status can be used, for example, in applications such as real-time heart rate, continuous blood pressure, monitoring of cardiovascular function, and the like. Moreover, in order to improve the quality of life and convenience, portable or wearable measurement methods will gradually become the mainstream, while traditional on-site measurement methods (for example, medical instruments such as blood pressure machines used in medical institutions) will gradually decline. In order to achieve portable or wearable non-invasive measurement, most common measurement methods use optics or mechanics (for example, piezoelectric conversion) as the measurement mechanism.

However, the use of optics or mechanics is very easy to face the problem of insufficient measurement accuracy due to environmental interference. And the individual differences of the subjects/users (for example, skin color, cutin thickness, body shape) will cause errors in the measurement of optical or mechanical mechanisms, resulting in measurement errors obtained by traditional portable or wearable measurement devices. Values are not trusted.

Therefore, while pursuing the portability or convenience of the device, it will be a major focus of technical development in this field to avoid measurement errors caused by individual differences among users.

One of the objectives of the present invention is to provide a non-invasive blood vessel state measurement device and method that avoids measurement errors caused by individual differences among users.

The invention provides a blood vessel state measurement device, which includes a coil group, a signal source and a processing module. The coil group outputs the first electromagnetic signal to the target area to generate eddy current in the target area, and receives the second electromagnetic signal generated corresponding to the eddy current. The signal source is coupled to the coil set and outputs an AC signal to the coil set to generate the first electromagnetic signal. The processing module is coupled to the coil set and calculates characteristic signals according to the first electromagnetic signal and the second electromagnetic signal. Wherein the characteristic signal corresponds to at least one state of at least one blood vessel in the target area.

The present invention provides a blood vessel state measurement method, which includes: outputting a first electromagnetic signal to a target area to generate an eddy current in the target area; receiving a second electromagnetic signal corresponding to the eddy current; and according to the first electromagnetic signal and the second electromagnetic signal The signal calculation is a characteristic signal corresponding to at least one state of at least one blood vessel in the target area.

As mentioned above, the electromagnetic signal is output through the coil group to cause the blood vessels in the target area to generate magnetoelectric effect. The magnetoelectric effect can effectively avoid the measurement errors caused by the individual differences of the subjects/users.

100: Vascular state measuring device

110: coil group

120: signal source

130: Processing module

140: Matching components

150: Depth detection module

160: Communication module

170: barrier element

171: Gap

500: electronic device

MS1: First Electromagnetic Signal

MS2: Second Electromagnetic Signal

TA: target area

AS: AC signal

FS: characteristic signal

I: eddy current

V: blood vessel

FIG. 1 is a schematic diagram of a blood vessel state measuring device according to an embodiment of the present invention.

FIG. 2 is a signal diagram of blood vessel characteristic signal measurement in an embodiment of the present invention.

FIG. 3 is a schematic diagram of setting a matching element in an embodiment of the present invention.

FIG. 4 is a schematic diagram of a blood vessel state measuring device measuring blood vessel depth according to an embodiment of the present invention.

FIG. 5 is a schematic diagram of a blood vessel state measuring device coupled to an electronic device according to an embodiment of the present invention.

FIG. 6 is a schematic diagram of an arrangement of barrier elements in an embodiment of the present invention.

7A-7C are flowcharts of a method for measuring a blood vessel state in an embodiment of the present invention.

The drawings are presented to help describe various aspects of the present invention. In order to simplify the drawings and highlight the content to be presented in the drawings, the known structures or elements in the drawings may be drawn in a simple schematic manner or presented in an omitted manner . For example, the number of elements may be singular or plural. These figures are provided merely to illustrate these aspects and not to limit them.

Any reference to an element herein using a designation such as "first," "second," etc. generally does not limit the number or order of those elements. Rather, these designations are used herein as a convenient way of distinguishing between two or more elements or instances of an element. Therefore, it should be understood that designations "first", "second", etc. in the claims do not necessarily correspond to the same designations in the written description. Furthermore, it should be understood that reference to first and second elements does not mean that only two elements may be used or that the first element must precede the second element. "Includes", "including", "has", "containing" and so on used in this article are all open terms, meaning including but not limited to.

The term "coupled" is used herein to refer to a direct or indirect electrical coupling between two structures. For example, in one example of indirect electrical coupling, one structure may be coupled to another structure via a passive element such as a resistor, capacitor, or inductor.

In the present invention, the words "exemplary" and "for example" are used to mean "serving as an example, instance or illustration". Any implementation or aspect described herein as "exemplary", "such as" is not necessarily construed as preferred or advantageous over other aspects of the invention. The terms "about" and "approximately" as used herein with respect to a stated value or characteristic are intended to mean within a certain value (eg, 10%) of the stated value or characteristic.

In the present invention, the "vascular state" referred to herein is, for example but not limited to, vasoconstriction and/or dilation, vascular elasticity, intravascular state (for example, whether the inside of the blood vessel is blocked or smooth, blood flow state, etc.), vascular hyperplasia, Vessel density, vessel wall state (eg, whether the vessel wall is damaged).

Please refer to FIG. 1 . FIG. 1 illustrates a blood vessel state measuring device 100 including a coil set 110 , a signal source 120 and a processing module 130 . The coil set 110 outputs the first electromagnetic signal MS1 to the target area TA to generate the eddy current I in the target area TA, and receives the second electromagnetic signal MS2 generated corresponding to the eddy current I. The signal source 120 is coupled to the coil set 110 and outputs the AC signal AS to the coil set 110 to generate the first electromagnetic signal MS1. The processing module 130 is coupled to the coil set 110 and calculates the characteristic signal FS according to the first electromagnetic signal MS1 and the second electromagnetic signal MS2. The feature signal FS corresponds to at least one state of at least one blood vessel in the target area TA.

Specifically, the signal source 120 can be an AC signal generator formed by integrating active components (such as oscillators, timers) and/or passive components (such as resistors and capacitors) on a printed circuit board, or Any known device or device for generating AC signals. The processing module 130 can be a module formed by components such as a microprocessor, field programmable logic gate (FPGA), application-specific integrated circuit (ASIC), etc. A device or device that performs a capability. It should be noted that the signal source can be controlled through the processing module, or through any control element coupled to the signal source.

The signal source 120 provides the AC signal AS to the coil set 110, and the coil set 110 generates the first electromagnetic signal MS1 due to the electromagnetic effect. The coil group 110 is specifically arranged in the target area TA outside. Roughly speaking, the position and direction of the coil assembly 110 can transmit most of the energy of the first electromagnetic signal MS1 to the blood vessel V in the target area TA. In a preferred embodiment, the setting angle of the coil group 110 is such that the emission direction of the first electromagnetic signal MS1 is aimed at a larger volume (or cross-sectional area) of blood flow in the blood vessel V covering the target area TA. In addition, although FIG. 1 only draws a group of coil groups 110, the coil group 110 of the present invention is not limited to its shape (for example, it can be circular, oval, square, etc.) or quantity (for example, two coils respectively produce Two magnetic fields (for example, two coils receiving two different AC signals or the same AC signal)). Different coil shapes or quantities can be selected according to the setting area and different needs.

The coil group 110 outputs the first electromagnetic signal MS1 to the target area TA so that the target area TA generates an eddy current I. Specifically, after the first electromagnetic signal MS1 is applied to the target area TA, the target area TA (for example, the Tissues, blood vessels or blood, which can be regarded as planar conductors, will generate eddy current I correspondingly due to the first electromagnetic signal MS1. The eddy current I will generate the second electromagnetic signal MS2 opposite to the direction of the magnetic field of the first electromagnetic signal MS1. The second electromagnetic signal MS2 will be received by the coil set 110 (that is, the second electromagnetic signal MS2 will generate a magnetoelectric effect on the coil set 110 ) to generate an induced AC signal. The processing module 130 will measure the induced AC signal and generate the characteristic signal FS. For example, the characteristic signal FS may be the measured impedance variation of the coil assembly 110 , or the variation of the first electromagnetic signal MS1 due to the influence of the second electromagnetic signal MS2 . In addition, the value of the second electromagnetic signal MS2 (for example, frequency variation, amplitude variation) can also be directly measured as the characteristic signal FS. The characteristic signal FS may, for example, correspond to the increase or decrease of the blood volume in the blood vessel V (for example, the blood volume in the blood vessel V increases and/or decreases according to the contraction and relaxation of the blood vessel V). For example, please refer to FIG. 2 . FIG. 2 is an example of the impedance variation (Y axis) of the coil set 110 as the characteristic signal FS. When the blood vessel contracts and/or relaxes, the vortex generated by the first electromagnetic signal MS1 in the target area TA The current I also changes accordingly (for example, due to the change of the blood volume in the blood vessel when the blood vessel contracts/dilates), and the second electromagnetic signal MS2 generated due to the eddy current I also produces a relative change amount. At this time, after the coil set 110 receives the second electromagnetic signal MS2, the second electromagnetic signal MS2 causes the processing module 130 to measure the impedance value of the coil set 110 to change (in this case, the processing module 130 can be an impedance meter). However, the above-mentioned embodiments are only examples, and are not intended to limit the blood vessel states and measurement mechanisms measured by the present invention.

In one embodiment, the blood vessel state measuring device further includes a matching element. Referring to FIG. 3 , the matching element 140 is disposed between the coil assembly 110 and the target area TA. The magnetic impedance of the matching element 140 is between the magnetic impedance of the target area TA and the magnetic impedance of the coil assembly 110 . Specifically, for the blood vessels (for example, arteries) located in the target area TA, when the coil set 110 is attached to the position closest to the target area TA, the matching element 140 can be arranged on the skin S outside the coil set 110 and the target area TA ( Or, between clothing, obstacles). Preferably, the magnetic impedance of the matching element 140 can be between the equivalent magnetic impedance of the target area TA to the skin S (or clothing, obstacles) and the equivalent magnetic impedance of the medium between the coil group 110 and the matching element 140. between. In this way, the energy loss during the energy transfer between the first electromagnetic signal MS1 and the second electromagnetic signal MS2 is reduced, so as to achieve the purpose of measuring the required signal or improving the signal-to-noise ratio with less energy. Avoid problems such as excessive energy causing injury to the subject or insufficient battery life of the device. However, the purpose of disposing the matching element 140 is not limited to the above examples.

In one embodiment, please refer to FIG. 4 , the blood vessel state measurement device 100 further includes a depth configured to send a detection signal DS to the target area TA and provide depth information DI corresponding to the at least one blood vessel V to the signal source 120. The detection module 150 enables the signal source 120 to adjust the frequency and/or amplitude of the AC signal AS according to the depth information DI. Alternatively, the depth detection module 150 provides the depth information DI to the control module 130 so that the control module 130 adjusts the impedance of the coil set 110 (for example, by adjusting the capacitance and/or inductance of the coil set 110 ). For example, the depth detection module 150 can be an optical (detection The detection signal is a light signal) or acoustic (the detection signal is a sound wave signal) and other penetrating (for example, through the skin or clothing) detection mechanism components. Measure the depth of blood vessels in the target area through ranging mechanisms such as time-of-flight (TOF), and provide the depth information DI to the control element of the signal source 120 (in this embodiment, the processing module 130), and process The module 130 adjusts the frequency and/or amplitude of the AC signal AS output by the signal source 120 according to the depth information DI, or adjusts and adjusts the capacitance and/or inductance of the coil group 110 to achieve a better effect (for example, to generate a better large eddy current I or receiving a large second electromagnetic signal MS2, etc.).

In an embodiment where the capacitance and/or inductance of the coil set 110 is adjusted, the coil set may, for example, be coupled to an adjustable capacitor and/or inductor. Specifically, before the signal source 120 outputs the AC signal AS, adjust the value of the adjustable capacitor and/or inductor to obtain the maximum response (for example, increase or decrease the capacitance value and/or the inductance value of the coil group 110 to perform most suitable capacitance value and/or inductance value range), or adjust the capacitance value and/or inductance value of the coil group 110 according to the depth information DI obtained by the depth detection module 150 (for example, establish a depth-impedance value mapping table, when the vessel depth is known, measure with a known suitable impedance value), or a mixture of the above methods. In this embodiment, the signal source 120 can provide the AC signal AS with a fixed frequency, and only change the ratio (LC value) of the capacitance and inductance of the coil assembly 110 to achieve the effect of adjusting the first electromagnetic signal MS1. By adjusting the capacitance of the adjustable capacitor, the first electromagnetic signal MS1 can generate a larger response (ie, a larger eddy current I or a larger second electromagnetic signal MS2 ) after it is output to the target area TA.

However, the mechanism for adjusting the AC signal AS output by the signal source 120 is not limited to receiving the depth information DI provided by the depth detection module 150 . In one embodiment, before the signal source 120 outputs the AC signal AS, the signal source 120 outputs a frequency scanning signal corresponding to a frequency interval in the blood vessel state measuring device 100, and the frequency when the AC signal AS is output can be selected from the frequency scanning signal. produce a response The frequency of the largest. Specifically, the signal source 120 sequentially outputs AC signals of different frequencies (eg, in a manner of increasing or decreasing frequency) in a possible frequency range (eg, kilohertz to megahertz). Scanning the AC signals with different frequencies may cause the target area TA to generate different magnitudes of eddy current I, and correspondingly generate different magnitudes of responses (for example, generate different magnitudes of the second electromagnetic signal MS2). The processing module 130 can determine the frequency of the AC signal AS output by the signal source 120 according to the transmission frequency corresponding to the maximum or best response among the responses received by the coil set 110 . In this way, it is possible (for example but not limited) to make the blood vessel state measuring device 100 measure with a more suitable AC signal AS to obtain a better effect (eg, better signal-to-noise ratio).

In one embodiment, as shown in FIG. 5 , the blood vessel state measuring device 100 further includes a communication module 160 coupled to the processing module 130 and configured to output the characteristic signal FS to the electronic device 500 . Specifically, the electronic device 500 is, for example, a backend device such as a smart phone, a desktop computer, or a notebook computer. The communication module 160 communicates with the electronic device 500 wirelessly (eg, bluetooth, wireless network, infrared, etc.) or wired (eg, wired network or cable, etc.) and provides the characteristic signal FS to the electronic device 500 . An application program can be installed in the electronic device 500 to record or analyze the characteristic signal FS. In this way, the purpose of tracking or evaluating the state of blood vessels can be achieved, but not limited thereto.

In an embodiment, please refer to FIG. 6 , the blood vessel state measurement device 100 further includes a blocking element 170 . The blocking element 170 is disposed between the coil set 110 and the target area TA (can be disposed alone or together with the matching element 140 ). The barrier element 170 has a notch 171 . The first part P1 of the first electromagnetic signal MS1 pointing to the target area TA can pass through the gap 171 (not blocked), and the blocking element 170 blocks the second part P2 of the first electromagnetic signal MS1 that does not pass through the gap 171 (blocked by the blocking element 170 and not blocked). impenetrable). Specifically, the material of the blocking element 170 is an electric conductor or a magnetic conductor material or other materials capable of blocking electromagnetic waves. Although the first electromagnetic signal MS1 is directed toward the target by the coil set 110 Issued for area TA. However, the first electromagnetic signal MS1 still has a part (ie, the second part P2 ) that diverges (for example, the magnetic flux diverges and does not point to the target area TA). Therefore, the second part P2 of the first electromagnetic signal MS1 does not completely (or cannot) act on the target area TA, and noise may be generated. The generated noise may interfere with the first part P1 of the first electromagnetic signal MS1 (the part where the first electromagnetic signal is sent toward the target area but not diverged) and/or the second electromagnetic signal MS2 generated in response to the eddy current I. In this embodiment, through the gap 171 of the blocking element 170, the first part P1 of the first electromagnetic signal MS1 can pass through the blocking element 170 without being shielded by the blocking element 170, and the second part P2 of the first electromagnetic signal MS1 will Shielded by blocking element 170 . By disposing the blocking element 170, for example, the purpose of improving the signal-to-noise ratio can be achieved. In addition, the notch 171 can be a circular notch, a square notch or other shapes according to the shape of the coil assembly 110 . It should be noted that the shape and/or location of the notch 171 can be adjusted according to actual needs.

Referring to FIG. 7A , a method for measuring a blood vessel state is illustrated. Step S1: output the first electromagnetic signal to the target area to generate eddy current in the target area; step S2: receive the second electromagnetic signal corresponding to the eddy current; and step S3: calculate the corresponding A characteristic signal of at least one state of at least one blood vessel in the target area. In addition, in an embodiment, step S4 may be included: outputting the feature signal to an electronic device for subsequent calculation or statistics.

In one embodiment, please refer to FIG. 7B. FIG. 7B illustrates that before step S1 outputs the first electromagnetic signal to the target area, there may also be a step S1-1: setting a matching element between the output end of the first electromagnetic signal and the target area To reduce the difference in electromagnetic impedance between the output and the target area. In addition, in step S1-1, a blocking element may also be disposed between the output end of the first electromagnetic signal and the target area. The blocking element has a gap, the first part of the first electromagnetic signal directed to the target area can pass through the gap, and the blocking element blocks the second part of the first electromagnetic signal not passing through the gap. In other words, the first part because the gap does not Unblocked by barrier elements, it can be delivered to the target area. However, the second part is not delivered to the target area because it is blocked by the blocking element. It should be noted that the matching element and the blocking element can be set together or separately, and can be adjusted according to actual needs. The present invention is not limited.

In one embodiment, please refer to FIG. 7C . FIG. 7C illustrates that before step S1 of outputting the first electromagnetic signal to the target area, there may be step S1-2: adjusting and/or optimizing the output parameters of the first electromagnetic signal. For example, in one embodiment, the depth information of blood vessels corresponding to the target area can be measured, and the frequency or amplitude of the first electromagnetic signal can be adjusted according to the depth information. In one embodiment, a frequency-sweeping electromagnetic signal corresponding to a frequency range may be output, and the frequency of the first electromagnetic signal is selected from the frequency with the largest response among the frequency-sweeping electromagnetic signals. In one embodiment, the adjustment and/or optimization of the first electromagnetic signal can be achieved by changing the ratio (LC value) of the capacitance to the inductance of the coil group. In this embodiment, for example, by scanning the capacitance and/or inductance values or establishing a depth-LC value correspondence relationship based on the obtained depth information, the first electromagnetic signal can generate a larger response (that is, a larger eddy current generation or a larger second electromagnetic signal). In addition, the step S1-2 can dynamically adjust and/or optimize the output parameters of the first electromagnetic signal according to the actual measurement results (for example, the signal-to-noise ratio of the characteristic signal) during the measurement process.

The previous description of the invention is provided to enable one of ordinary skill in the art to make or practice the invention. Various modifications to the invention will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other changes without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the examples described herein but is to be accorded the widest scope consistent with the principles and novel features of the invention herein.

100 Vascular state measuring device 110 coil set 120 signal sources 130 processing modules MS1 first electromagnetic signal MS2 second electromagnetic signal TA target area AS AC signal FS characteristic signal I eddy current V vessel

Claims (12)

A blood vessel state measurement device, comprising: a coil group, outputting a first electromagnetic signal to a target area to generate an eddy current in the target area, and receiving a second electromagnetic signal corresponding to the eddy current; a signal source , coupled to the coil set, the signal source outputs an AC signal to the coil set to generate the first electromagnetic signal; a processing module, coupled to the coil set, the processing module according to the first electromagnetic signal and The second electromagnetic signal calculates a characteristic signal; and a blocking element is disposed between the coil group and the target area, the blocking element has a gap through which a first part of the first electromagnetic signal directed to the target area passes through the gap , and the blocking element blocks a second portion of the first electromagnetic signal that does not pass through the gap; wherein the characteristic signal corresponds to at least one state of at least one blood vessel at the target area. The blood vessel state measuring device according to claim 1, further comprising: a matching element, disposed between the coil set and the target area, the magnetic impedance of the matching element is between the magnetic impedance of the target area and the coil set Between the magnetic impedance. The blood vessel state measurement device as described in claim 1, further comprising: a depth detection module configured to send a detection signal to the target area, and provide a depth information corresponding to the at least one blood vessel to the A signal source, the signal source adjusts the frequency or amplitude of the AC signal according to the depth information. The blood vessel state measurement device as described in Claim 1, wherein before the signal source outputs the AC signal, the signal source outputs a frequency scanning signal corresponding to a frequency interval, and the frequency of the AC signal is selected from the frequency scanning signal response The frequency of the largest. The blood vessel state measuring device according to claim 1, wherein the coil group is coupled to an adjustable capacitor, and before the signal source outputs the AC signal, the adjustable capacitor is adjusted to a first value to obtain a maximum response. The blood vessel state measurement device as described in claim 1 further includes: a communication module coupled to the processing module, and the communication module is configured to output the characteristic signal to an electronic device. A blood vessel state measurement method, comprising: outputting a first electromagnetic signal to a target area to generate an eddy current in the target area; receiving a second electromagnetic signal corresponding to the eddy current; according to the first electromagnetic signal and the The second electromagnetic signal calculates a characteristic signal corresponding to at least one state of at least one blood vessel at the target area; and before outputting the first electromagnetic signal to the target area, disposing a blocking element on one of the first electromagnetic signals Between the output end and the target area, the blocking element has a gap, a first part of the first electromagnetic signal directed to the target area passes through the gap, and the blocking element blocks a first part of the first electromagnetic signal that does not pass through the gap two parts. The blood vessel state measurement method according to claim 7, further comprising: before outputting the first electromagnetic signal to the target area, a matching element is arranged between an output terminal of the first electromagnetic signal and the target area to A difference in electromagnetic impedance between the output and the target area is reduced. The blood vessel state measurement method as described in claim item 7, further comprising: before outputting the first electromagnetic signal to the target area, measuring a depth information corresponding to at least one blood vessel, and adjusting the first one according to the depth information The frequency or amplitude of an electromagnetic signal. The blood vessel state measurement method according to claim 7, further comprising: before outputting the first electromagnetic signal to the target area, outputting a frequency scanning electromagnetic signal corresponding to a frequency interval, the frequency of the first electromagnetic signal is selected from The frequency scans the frequency of the most responsive electromagnetic signal. The blood vessel state measurement method as described in Claim 7, wherein the first electromagnetic signal is sent by a coil group, and the capacitance value coupled to the coil group is adjusted before outputting the first electromagnetic signal to the target area to a first value that obtains the maximum response. The blood vessel state measuring method as described in Claim 7 further includes: outputting the characteristic signal to an electronic device.

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