JP2007267977A - Vascular lumen diameter measuring device - Google Patents

Abstract

To provide a blood vessel lumen diameter measuring apparatus capable of accurately measuring the lumen diameter of a blood vessel under the skin of a living body.
According to a vascular endothelial function testing device (blood vessel lumen diameter measuring device) 30, measurement is performed by a biological information measuring device 68 at least in a rest period A provided before stimulating the artery 20. Since the biological information is displayed and output on the image display device (display device) 34, the resting state of the living body 14 in the resting period A can be easily confirmed. Therefore, only the measurement values for the living body that has confirmed the resting state are employed. Thus, the lumen diameter d of the blood vessel under the skin 18 of the living body 14 can be accurately measured.
[Selection] Figure 4

Description

  The present invention relates to a blood vessel lumen diameter measuring apparatus that repeatedly measures the lumen diameter of a blood vessel under the skin of a living body in order to obtain a change rate of the lumen diameter.

  For example, in order to evaluate the vascular endothelial function, as described in FIG. 9 of Patent Document 1, the rate of change in blood vessel diameter (FMD (blood flow-dependent vasodilator response) after ischemic reactive hyperemia) ( % FMD), it is necessary to accurately measure the blood vessel diameter before and after ischemia. However, since the blood vessel diameter is uniformly measured after a certain resting time without considering the physiological state of the living body that affects the blood vessel diameter, whether the measured blood vessel diameter is a change in the blood vessel diameter reflecting the endothelial function, It was unclear whether changes in other biological parameters or psychological influences were included, and it was difficult to say that accurate changes in lumen diameter were necessarily measured.

On the other hand, as shown in FIG. 3 of Non-Patent Document 1, the blood flow increase rate together with the blood vessel diameter increase rate is displayed on a common time axis, or as shown in FIG. It is done to display. However, as a cause of FMD, the increase in shear stress (shear stress) due to blood flow at the time of release of ischemia produces nitric oxide NO, and as a result, blood flow is monitored in order to monitor the promising explanation that blood vessel diameter is increased. I'm just measuring. In such a device, only a change in blood flow after the release of ischemia is displayed, and it does not indicate biological information, so it cannot be determined whether or not the living body is in a resting state.
JP 2003-245280 A "Vessel Failure Frontier" December 1, 2004, issued by Medical Review Inc., pages 182-183, Figs.

  As described above, the blood vessel diameter measuring device is a change in blood vessel diameter representing FMD (blood flow-dependent vasodilatation reaction) after ischemic reactive hyperemia to evaluate arterial vascular endothelial function based on a slight diameter change. Used to determine the rate (% FMD). The arterial vascular endothelial function test is performed by measuring the lumen diameter of the arterial blood vessel after the rest period has been set, for example, about 15 minutes, and then measuring the lumen diameter of the arterial blood vessel after release of the ischemia. The change rate (% FMD), which is the ratio of the maximum value of the lumen diameter of the arterial blood vessel after the release of ischemia to the lumen diameter, is performed.

  However, the time required for each individual living body to obtain a resting state varies depending on individual differences and the situation immediately before measurement, and the living body after the uniform resting period has not necessarily been in a resting state. Although there was a problem, the lumen diameter of the arterial blood vessel is measured when the living body is not at rest, so that a large error is included in the lumen diameter, and the change rate of the lumen diameter calculated from the error (% FMD) ) May not be reliable.

  The present invention has been made in the background of the above circumstances, and an object of the present invention is to provide a blood vessel lumen diameter measuring device capable of accurately measuring the lumen diameter of a blood vessel under the skin of a living body. It is in.

  In order to achieve the above object, the gist of the invention according to claim 1 is to obtain a rate of change in the lumen diameter of a blood vessel, after giving a stimulus to the living body, the lumen diameter of the blood vessel of the living body. A blood vessel lumen diameter measuring device that repeatedly measures (a) a display, and (b) a biological information measuring device that measures biological information generated in connection with the activity of the autonomic nerve of the living body from the living body, (c) It includes display means for causing the display to display and output the biological information measured by the biological information measuring device at least during a rest period provided before the stimulation.

  According to the blood vessel lumen diameter measuring device of the invention according to claim 1, the activity of the autonomic nerve of the living body measured by the living body information measuring device at least during a rest period provided before stimulating the blood vessel. Since the biological information generated in association with the display is output on the display, the resting state of the living body during the resting period can be easily confirmed from the biological information generated in relation to the activity of the autonomic nerve. By adopting only the measured values for the living body, the lumen diameter of the blood vessel under the skin of the living body can be accurately measured.

  Here, it is preferable that the biological information measuring device repeatedly measures the biological information during the rest period, and the display means displays the biological information repeatedly measured during the rest period, as the display unit. Are displayed in time series. In this way, there is an advantage that the resting state of the living body can be easily recognized based on the change of the biological information repeatedly measured during the resting period.

  Preferably, the indicator displays a two-dimensional coordinate having a time axis including the rest period and the period after the stimulus is released, and the lumen diameter is set in the period after the stimulus is released. It is repeatedly measured, and the display means displays the lumen diameter or its rate of change and the biological information in a graph along the time axis. In this way, there is an advantage that the biological information can be grasped at the timing when the lumen diameter of the blood vessel is measured.

  Preferably, the biological information measuring device measures at least one of the heart rate, respiratory rate, blood pressure, body temperature, and electroencephalogram of the living body as the biological information. In this way, there is an advantage that the resting state of the living body can be easily grasped.

  Preferably, the stimulation on the blood vessel compresses a part of the living body to block a continuous blood vessel in the part of the living body and then releases the pressure to resume blood flow in the blood vessel. Sometimes shear stress applied to the endothelial cells of the blood vessel. In this way, there is an advantage that a stimulus to a blood vessel can be given without being invasive.

  Preferably, the rest period on the time axis has a shorter time per unit length than the release period, and more preferably a longer time per unit length than the period after release of the ischemia. It is set to be. In this way, changes in biological information can be easily seen in a limited display area.

  FIG. 1 shows an ultrasonic probe (ultrasonic probe) 12 held by a sensor holding device 10 according to an embodiment of the present invention, and the skin 18 of an upper arm 16 of a living body 14 which is a detection target is viewed from above. It is a front view explaining the vascular endothelial function test | inspection apparatus 30 provided with the blood vessel image display apparatus 22 which displays the cross-sectional image (short-axis image) or longitudinal cross-sectional image (long-axis image) of the arterial blood vessel 20 located just under the skin 18. FIG. is there. This vascular endothelial function testing device 30 is used to obtain a change rate (% FMD) of a blood vessel diameter representing FMD (blood flow-dependent vasodilatation reaction) after ischemic reactive hyperemia in order to evaluate vascular endothelial function. After the blood is blocked for a certain time by the compression of the cuff 88 wound around the cuff 88, the change in the blood vessel diameter after the release of the cuff 88 by the release of the cuff 88 is obtained. It also functions as a measuring device.

  The ultrasonic probe 12 also functions as a blood vessel diameter sensor. For example, the ultrasonic probe 12 is formed by arranging a plurality of ultrasonic transducers made of piezoelectric ceramics in a single row or parallel to each other. A tip portion 24 including two rows of ultrasonic arrays 24 a is provided on the probe main body 28 via a triaxial drive mechanism 26.

  The vascular endothelial function testing device 30 includes an electronic control device 32 constituted by a so-called microcomputer, an image display device 34 for monitoring, a keyboard 36 and a mouse 37 which are input operation devices, and an ultrasonic drive control circuit 38. The electronic control device 32 supplies a drive signal from the ultrasonic drive control circuit 38 to emit ultrasonic waves from the ultrasonic array at the distal end portion 24 of the ultrasonic probe 12, and the ultrasonic array at the distal end portion 24. By receiving the ultrasonic reflection signal SR detected by the above-described processing and processing the ultrasonic reflection signal SR, an ultrasonic cross-sectional image under the skin 18 is generated and displayed on the image display device 34. The lower end surface of the distal end portion 24 corresponds to the radiation surface S that emits ultrasonic waves. Further, when generating a cross-sectional image (short axis image) of the blood vessel 20, the electronic control device 32 drives the three-axis positioning mechanism 26 so that the ultrasonic array is at a position orthogonal to the blood vessel 20. Therefore, when generating a longitudinal section image (long axis image) of the blood vessel 20, the ultrasonic array is positioned by the triaxial positioning mechanism 26 so as to be parallel to the blood vessel 20.

  In accordance with a command from the electronic control unit 32, the ultrasonic drive control circuit 38 has a certain number of ultrasonic transducers (piezoelectric ceramics) arranged in a line constituting the ultrasonic array from its end. By applying beam forming at a frequency of about 10 MHz while giving a predetermined phase difference to each ultrasonic transducer group, a convergent ultrasonic beam is sequentially emitted toward the blood vessel 20 in the arrangement direction of the ultrasonic transducers. The reflected wave for each radiation is received and input to the electronic control unit 32. An acoustic lens for converging the ultrasonic beam in a direction orthogonal to the arrangement direction of the ultrasonic transducers is provided on the radiation surface of the ultrasonic array.

  The electronic control unit 32 synthesizes an ultrasonic cross-sectional image based on the reflected wave detected by the ultrasonic array, generates a cross-sectional image (short axis image) of the blood vessel 20 under the skin 18, or A longitudinal section image (long axis image) is generated and displayed on the image display device 34. In addition, the inner diameter or lumen diameter (intimal diameter) of the blood vessel 20 is calculated from the image. In order to evaluate the vascular endothelial function, the change rate (%) of the endothelial diameter (intimal diameter) of the blood vessel representing FMD (blood flow-dependent vasodilatation reaction) after ischemic reactive hyperemia [= 100 × ( dmax−d) / d] (where d is the vascular lumen diameter at rest and dmax is the maximum vascular lumen diameter after release of ischemia). When the blood vessel lumen diameter is detected, an accurate flow cross-sectional area of the blood vessel 20 is calculated. For example, an accurate blood flow rate can be calculated using a blood flow velocity detected by an ultrasonic Doppler device.

  The ultrasonic probe 12 does not deform the blood vessel 20 located just below the skin 18 from the skin 18 of the upper arm 16 of the living body 14 which is a detection target at a desired position in the three-dimensional space, that is, a predetermined position. The sensor holding device 10 is held in a desired posture in a state where it is lightly contacted. The ultrasonic probe 12 is generally well-known between the end face of the distal end portion 24 and the skin 18 in order to clarify an ultrasonic cross-sectional image by suppressing ultrasonic attenuation, reflection and scattering at the boundary surface. A coupling agent such as jelly is interposed. This jelly is a gel-like water-absorbing polymer containing water at a high rate, for example, agar, etc., and has a sufficiently higher specific impedance (= sound speed × density) than air to suppress attenuation of ultrasonic transmission / reception signals Is. Further, instead of the jelly, a water bag in which water is confined in a resin bag, olive oil, glycerin, or the like can be used.

  The sensor holding device 10 is provided in a fixed position on a desk, a pedestal or the like, and has a base 42 having a fitting hole 40 formed in the direction of the vertical rotation axis C, and a relative position in the fitting hole 40. A rotation member 46 that includes a fitting shaft 44 that is rotatably fitted, is provided so as to be rotatable about a rotation axis C perpendicular to the base 42, and is fixed to the rotation member 46. The first link mechanism 48 includes four links 48a to 48d including the first fixed link 48a, and the four links 50a to 50d include the first fixed link 50a fixed to the distal end portion of the first link mechanism 48. The second link mechanism 50, the universal joint 52 which is fixed at the distal end of the second link mechanism 50 and rotatably connects the ultrasonic probe 12 and supports the second probe mechanism 50, and the operation lever 54 is not operated. Always turn the joint 52 Fixed, and a stopper device 56 for releasing acceptable i.e. the fixed state the times songs that were fixed at all times in accordance with operation of the operating lever 54.

  The first link mechanism 48 includes a pair of first fixed links 48a and first movable links 48b parallel to each other, and the pair of first fixed links 48a and first movable links so as to form a parallelogram. A pair of first rotation links 48c and 48d parallel to each other are rotatably connected to both ends of 48b, and the first movable link 48b moves in a plane including the rotation axis C. Thus, the first fixed link 48a is fixed to the rotating member 46. The first link mechanism 48 is provided with a first coil spring 49 that functions as a first urging device that generates a thrust having a directional component against the load applied to the first movable link 48b. . The first coil spring 49 is stretched between a connection point between the first rotation link 48c and the first fixed link 48a and a connection point between the first rotation link 48d and the first movable link 48b. The first movable link 48b generated by the moment that pulls up the first movable link 48b generated by the first coil spring 49 and the load applied to the first movable link 48b. The moment in the downward pulling direction is substantially canceled out.

  The second link mechanism 50 has a pair of second rotation links 50c and 50d that are parallel to each other, and rotates at both ends of the pair of second rotation links 50c and 50d so as to form a parallelogram. A pair of second fixed links 50a and a second movable link 50b that are movably connected to each other, and the second fixed link 50b is moved so as to move within a plane including the rotation axis C. The link 50a is fixed in a posture substantially orthogonal to the first movable link 48b. The second link mechanism 50 is provided with a second coil spring 51 that functions as a second urging device that generates a thrust having a directional component against a load applied to the second movable link 50b. The second coil spring 51 is stretched between a connection point between the second rotation link 50c and the second fixed link 50a and a connection point between the second rotation link 50d and the first movable link 50b. The second movable link 50b generated by the second coil spring 51 and the moment in the direction of pulling up the second movable link 50b upward and the load applied to the second movable link 50b. The moment in the downward pulling direction is substantially canceled out. Due to the canceling action of the first coil spring 49 and the second coil spring 51 as described above, the ultrasonic probe 12 is held at a desired position in the three-dimensional space or is slowly lowered, and the blood vessel 20 is deformed. The tip portion 24 of the ultrasonic probe 12 can be lightly adhered in a surface contact state via a coupling agent such as jelly to such an extent that it does not occur.

  As shown in an enlarged view in FIG. 2, the universal joint 52 includes a first connecting member 52a having a distal end portion 58 having a base end portion fixed to the second movable link 50b and formed in a spherical shape, and a first connection member 52a. A second connecting member 52b provided with a fitting hole 60 into which the spherical tip 58 of the connecting member 52a is slidably fitted, and connected so as to be capable of relative turning around the spherical center B of the spherical tip 58. The ultrasonic probe 12 is held in a desired posture.

  The stopper device 56 includes an operation lever 54 guided by a pair of guide holes 62 and 64 provided in the second connecting member 52b so as to be able to approach and separate from the spherical tip 58, and the operation lever 54 in a spherical shape. And a pressing spring 66 that presses against the distal end portion 58. Normally, when the operating lever 54 is not operated, the operating lever 54 is pressed against the spherical distal end portion 58 by the pressing spring 66. The joint 52 is prevented from turning and is always fixed, but when the operation lever 54 is operated against the urging force of the pressing spring 66, the operation lever 54 is separated from the spherical tip 58. The fixing of the universal joint 52 is released and its turning is allowed.

  Returning to FIG. 1, the vascular endothelial function testing device 30 is provided with a biological information measuring device 68 that measures and outputs biological information that is information representing the autonomous activity of the living body 14. This biological information is closely related to the activity of the autonomic nerve of the living body 14 and corresponds to the activity of the autonomic nerve, particularly the sympathetic nerve. The heart rate sensor 68a detects, for example, an R wave periodically included in an electrocardiographic induction signal that is a surface potential generated between a plurality of electrodes adhered to the living body 14, and measures a pulse signal representing the R wave as a biological information measurement. Supply to device 68. The biological information measuring device 68 calculates the heart rate HR (1 / min) of the living body 14 based on the number of R waves per unit time, for example, the number per minute. The respiration rate sensor 68 b detects, for example, the expiratory temperature of the nostril and supplies a signal representing the expiratory temperature to the biological information measuring device 68. The biological information measuring device 68 calculates the respiration rate RR (1 / min) of the living body 14 based on the change of the expiration temperature per unit time, for example, per minute. For example, the blood pressure sensor 68c detects the internal pressure by pressing the arterial blood vessel until the tube wall becomes flat, and supplies a signal representing the internal pressure to the biological information measuring device 68. The biological information measuring device 68 calculates a systolic blood pressure value Psys and a diastolic blood pressure value Pdia for each beat based on a signal representing the internal pressure from a relationship obtained in advance. The oxygen saturation sensor 68d is a so-called photoelectric pulse oximeter sensor (probe), and supplies a signal representing transmitted light intensity of two wavelengths to the biological information measuring device 68. The biological information measuring device 68 calculates the oxygen saturation SpO2 (%) based on a signal representing the transmitted light intensity of the two wavelengths from the relationship obtained in advance. The electroencephalogram sensor 68e detects an electroencephalogram BW, which is a surface potential generated between a plurality of electrodes adhered to the head of the living body, and supplies a signal representing the electroencephalogram to the biometric information measuring device 68.

  The biological information measuring device 68 displays the calculated heart rate HR, respiration rate RR, systolic blood pressure value Psys and diastolic blood pressure value Pdia, oxygen saturation SpO2, and electroencephalogram BW in a time-series trend display on its own monitor screen 68f, In order to display on the image display device 34, signals representing the plurality of types of biological information are supplied to the vascular endothelial function testing device 30.

  FIG. 3 is a diagram showing in detail the electrical configuration including the ultrasonic array 24a provided at the distal end portion 24 of the ultrasonic probe 12 of this embodiment, the ultrasonic drive control circuit 38, and the electronic control unit 32. . In FIG. 3, the ultrasonic drive control circuit 38 sequentially emits a convergent ultrasonic beam toward the blood vessel 20 positioned in a direction orthogonal to the arrangement direction of the ultrasonic transducers E according to a command from the electronic control device 32. Therefore, among the multiple ultrasonic transducers (piezoelectric ceramics) E arranged in a line along the direction intersecting the blood vessel 20 in order to form the ultrasonic array 24a, one by one is sequentially shifted from the end thereof. For example, beam forming is performed so that a single period of vibration having a frequency of about 10 MHz to which a predetermined phase difference is applied is output for each group of a constant number (one group) of about 16 to 32 ultrasonic transducers E. A drive signal for generating one cycle of ultrasonic pulses is supplied from the pulser 72 to each ultrasonic transducer E in accordance with a command from the circuit 70. For each ultrasonic radiation generated by the beam forming drive, the reflected wave from the boundary surface of the tube wall where the acoustic impedance changes suddenly is received by the ultrasonic array 24a, and the received signal is radiated by the multiplexer 74. A changeover switch 76 for preventing wraparound of ultrasonic waves, a receiver 78 with TGC having a gain adjustment and signal amplification function, a band-pass filter 80 for selectively passing a frequency of an ultrasonic reflected signal, that is, a signal of 10 MHz, The signal is supplied to the electronic control unit 32 through the A / D converter 82 and the beam forming circuit 70. Although not shown, the pulsar 72, the changeover switch 76, the receiver 78 with TGC, the band pass filter 80, and the A / D converter 82 are ultrasonic waves that emit ultrasonic waves to which a phase difference is added for the beam forming. A plurality of sets corresponding to the number of channels (a certain number of ultrasonic transducers) is provided. The beam forming circuit 70 is provided with a buffer function and an arithmetic function. Regarding the received signal, each reflected signal received by each ultrasonic transducer E is processed, and a group of ultrasonic waves emitting ultrasonic waves is processed. A reflection signal like a signal received by one ultrasonic transducer E located at the center of the transducer E is sequentially generated. The electronic control device 32 processes the reflection signal SR representing the reflected wave of the ultrasonic wave, and causes the image display device 34 to display the vascular lumen diameter d and the change rate (%) of the vascular lumen diameter as a processing result. In addition, the electronic control unit 32 causes the image display unit 34 to display the heart rate HR, the respiratory rate RR, the maximum blood pressure value Psys, the minimum blood pressure value Pdia, the oxygen saturation SpO2, and the electroencephalogram BW calculated by the biological information measuring device 68. .

  FIG. 4 is a functional block diagram illustrating a main part of the control function of the electronic control device 32. The reflected signal detection means 90 detects a reflected wave that passes through the vicinity of the center of the blood vessel 20 out of a series of reflected signals SR received by the ultrasonic array 24a, and causes a predetermined storage device to read it. This reflected signal SR is a digital signal with a sampling frequency of 100 MHz, for example, and shows a waveform composed of data points shown in the image of the reflected signal (RF signal) in FIG. One period of the reflected waveform shown in FIG. 5 corresponds to 10 MHz of the ultrasonic radiation wave. Although only one group of reflected waveforms SR1 is shown in FIG. 5, the reflected waves passing near the center of the blood vessel 20 include two groups of reflected waves SR1 and SR2 reflected from the tube wall of the blood vessel 20. The maximum distance between the reflected waves SR1 and SR2 or the maximum amplitude of the reflected waves is used.

  As is well known, for example, the ultrasonic cross-sectional image generating means 92 detects and squares the reflected wave signal of the ultrasonic wave to convert it to a signal corresponding to the signal power, and converts the signal power into an envelope. It is converted into a smooth signal that changes smoothly by processing and smoothing, and a grayscale signal is generated by converting the magnitude of the smoothed signal into a stepwise grayscale, and the two-dimensional signal indicated by the grayscale An ultrasonic cross-sectional image MG is generated.

  The detection means 94 executes a detection process (full wave rectification process) in which the negative portion of the reflected signal SR shown in FIG. 5 is positive, and as shown in FIG. 6, the absolute value of the reflected signal SR. Convert to a signal that shows the waveform. The peak time signal generating means 96 generates a peak time signal SP indicated by a data point indicating the peak size (peak value) of the waveform of the detected reflected signal SR and the time position of the peak. FIG. 7 shows the peak time signal SP, and the number of data points is 1/5 or less compared to the reflected signal SR after detection in FIG. The upper peak of the peak time signal SP is indicated by the data point, and the lower peak is located between the upper peaks and on the baseline. The waveform of FIG. 7 may be indicated by an envelope connecting those peaks.

  The measurement position determining means 98 uses the peak time of the two groups as an interval between the two groups of peak time signal waveforms corresponding to the two groups of waveforms corresponding to the blood vessel wall of the blood vessel 20 included in the peak time signal SP. The end point of the wave train located at the end of the peak time signal waveform of one group of the signal waveforms and the start point of the wave train located at the start of the peak time signal waveform of the other group are determined as measurement positions A1 and A2. To do. In FIG. 7, the peak time signal waveforms of the first group from the blood vessel wall on the side close to the skin are shown, and the measurement position A1, which is the end point of the wave train located at the end, is shown.

  The lumen diameter calculation unit 100 calculates a time interval t between the measurement position A1 and the measurement position A2 in the peak time signal SP determined by the measurement position determination unit 98, and stores a relationship (d = Based on the time interval from t × V), a predetermined timing in one beat, for example, the lumen diameter d of the blood vessel 20 at the time of diastolic blood pressure is sequentially and repeatedly calculated for each beat, for example. In this relation, V is the speed of sound in the living body, and for example, 1530 m / sec is used. Note that the lumen diameter d of the blood vessel 20 may be measured at the timing of the maximum blood pressure during one beat.

  Endothelial function evaluation value calculation means 102 calculates the relationship [= 100 × (dmax−d) / d] (where d is the vascular lumen diameter at rest before ischemia and dmax is within the ischemia release period C). Based on the vascular lumen diameter d and the maximum vascular lumen diameter dmax calculated by the lumen diameter calculating means 100, the lumen diameter change rate Δd (%) in the ischemia release period C is calculated from the maximum vascular lumen diameter). The maximum value of the lumen diameter change rate Δd after the end of the ischemia release period C is determined as% FMD which is an evaluation value for evaluating the vascular endothelial function. When a shear stress is applied to the endothelial cells of the artery 20 by starting blood flow by releasing the ischemia, a physiological phenomenon occurs in which the endothelial cells produce NO and consequently increase the blood vessel diameter. This increase in blood vessel diameter is said to be closely related to arteriosclerosis.

  The display means 104 displays the peak time signal used for calculating the lumen diameter d together with the lumen diameter d calculated by the lumen diameter calculation means 100 and the range on the waveform corresponding to the lumen diameter d. Two groups of SP peak time signal waveforms are displayed on the image display device 34. That is, as shown in the display example of FIG. 8, the display unit 104 generates the two groups of peak time signal waveforms of the peak time signal SP used for calculating the lumen diameter d and the ultrasonic cross-sectional image generation unit 92. The two-dimensional ultrasonic cross-sectional image MG thus displayed is displayed on the image display device 34 in parallel so that they can be compared with each other. In addition, the display unit 104 displays a trend graph showing a change over time of the lumen diameter d calculated by the lumen diameter calculation unit 100 after the release of ischemia and the vascular endothelial function calculated by the endothelial function evaluation value calculation unit 102. % FMD, which is an evaluation value for evaluation, is displayed at a predetermined display location on the screen of the image display device 34, for example, as shown in FIG.

  In the display example of the screen in the image display device 34 of FIG. 8, the two-dimensional ultrasonic cross-sectional image MG indicated by the shading generated by the ultrasonic cross-sectional image generating unit 92 is displayed on the left side of the screen by the peak time signal generating unit 96. The waveform shown by the envelope of the peak value of the peak time signal SP including the two groups of peak time signal waveforms SW1 and SW2 corresponding to the two groups of waveforms corresponding to the blood vessel walls of the blood vessel 20 is shown on the right side of the screen. Displayed in parallel as possible. In the above screen, the ultrasonic cross-sectional image MG is displayed so that the vertical direction corresponds to the depth direction from the skin, and the waveform of the peak time signal SP is such that the time axis, that is, the distance axis is vertical, that is, the depth. The path L of the reflected signal SR used for calculating the lumen diameter d is displayed in the ultrasonic cross-sectional image MG, and the waveform of the peak time signal SP is on the time axis. A corresponding baseline M is displayed. The two positions of the peak time signal waveforms SW1 and SW2 included in the peak time signal SP display the measurement positions A1 and A2 determined by the measurement position determination means 98 and are calculated by the lumen diameter calculation means 100. The lumen diameter d of the blood vessel 20 is displayed between the two groups of peak time signal waveforms SW1 and SW2 with a distance and a numerical value indicated by the length of the arrow. The lumen diameter d is displayed at a position corresponding to the blood vessel 20 in the ultrasonic cross-sectional image MG. The ultrasonic cross-sectional image MG is a black and white grayscale image called a so-called B-mode image, and an arrow indicating the position of the lumen diameter d is displayed inside the blood vessel 20 therein.

  In FIG. 4, the biological information measuring means 106 corresponds to the biological information measuring device 68, and a plurality of types of biological information indicating the autonomous activity state of the living body 14, for example, heart rate HR, respiratory rate RR, The hypertension value Psys, the minimum blood pressure value Pdia, the oxygen saturation level SpO2, and the electroencephalogram BW are measured and supplied to the display means 104 of the vascular endothelial function testing device 30. For example, as shown in FIG. 9, the display unit 104 displays the image at a predetermined display location on the screen of the image display device 34. As shown in FIG. 9, the two-dimensional coordinates having the time axis 108 and the biological parameter axis 110 are displayed on the display means 104 by the biological information measuring means 106 at least in the rest period A provided before the ischemic period B. The biological information repeatedly measured is displayed in a trend graph in a time series together with the lumen diameter d and the rate of change with respect to the value at rest. The time axis 108 has a rest period A of at least about 15 minutes, an ischemia period B of about 5 minutes, and an ischemia release period C. The rest time A is longer than the ischemic period B so that the display is easy to see. The time per unit length is long, and the time per unit length is set shorter than the ischemia release period C.

  In FIG. 9, t1 indicates the time when the rest period A ends and the ischemic period B starts, and t2 indicates the time when the ischemic period B ends and blood flow starts. The time t2 indicates the time when stimulation (increase in shear stress) due to increased blood flow is started on the endothelial cells of the artery 20 due to increased blood flow.

  As described above, according to the vascular endothelial function testing device (vascular lumen diameter measuring device) 30 of the present embodiment, at least in the rest period A provided before stimulating the artery 20, the biological information measuring device Since the biological information measured by 68 is displayed and output on the image display device (display device) 34, the resting state of the living body 14 in the resting period A can be easily confirmed. By adopting only the value, the lumen diameter d of the blood vessel under the skin 18 of the living body 14 can be accurately measured.

  In addition, according to the vascular endothelial function testing device (vascular lumen diameter measuring device) 30 of the present embodiment, the biological information measuring device 68 repeatedly measures biological information in the rest period A, and the display means 104 includes: Since the biological information repeatedly measured in the rest period A is displayed in time series along the time axis 108 on the display screen of the image display device 34, the change in the biological information repeatedly measured in the rest period A Based on the above, there is an advantage that the resting state of the living body can be easily recognized.

  In addition, according to the vascular endothelial function testing device (vascular lumen diameter measuring device) 30 of the present embodiment, the image display device 34 has a two-dimensional coordinate having a time axis 108 including a rest period A and a period C after releasing the stimulus. The lumen diameter d is repeatedly measured in the period C after the release of stimulation, and the display means 104 displays the lumen diameter d or its change rate (%) and biological information as time. Since the graph is displayed along the axis 108, there is an advantage that the biological information can be easily grasped at the timing when the lumen diameter d of the blood vessel is measured.

  In addition, according to the vascular endothelial function testing device (vascular lumen diameter measuring device) 30 of the present embodiment, the biological information measuring device 68 uses the heart rate HR, respiratory rate RR, blood pressure BP, oxygen of the living body 14 as biological information. Since at least one of the saturation SpO2 and the electroencephalogram BW is measured, there is an advantage that the activity state of the autonomic nerve of the living body can be easily grasped and the resting state of the living body 14 can be easily grasped.

  Further, according to the vascular endothelial function testing device (vascular lumen diameter measuring device) 30 of the present embodiment, stimulation of the endothelial cells of the artery 20 is performed by compressing the forearm part which is a part of the living body 14 with the cuff 88. This is a shearing stress applied to the endothelial cells of the artery 20 when the continuous artery 20 in the forearm of the living body 14 is occluded and then the pressure is released to resume blood flow in the artery 20. There is an advantage that stimulation to the artery 20 can be given by invasion.

  Further, according to the vascular endothelial function testing device (vascular lumen diameter measuring device) 30 of the present embodiment, the rest period A on the time axis 108 is shorter in time per unit length than the period C after releasing the heavy tree. More preferably, since the time per unit length is set to be longer with respect to the ischemic period B, there is an advantage that changes in biological information are easily seen in a limited display area.

  Further, according to the vascular endothelial function testing device (vascular lumen diameter measuring device) 30 of the present embodiment, when the reflected signal SR from the arterial blood vessel 20 when the ultrasonic wave is emitted from the ultrasonic probe 12 is detected, Based on the interval between the two groups of peak time signal waveforms SW1 and SW2 of the peak time signal SP corresponding to the two groups of reflected wave signals SR1 and SR2 from the vessel wall of the blood vessel 20 included in the reflected signal SR. And a lumen diameter calculating means 100 for calculating the blood vessel lumen diameter d. For this reason, the reflection signal SR and the peak time signal SP converted from the reflected signal SR contain all of the minute and weak amplitudes, so that important time information remains, and an envelope for displaying the ultrasonic cross-sectional image is displayed. Since the blood vessel lumen diameter d is calculated based on the interval between the two groups of reflected waves from the intima of the fine arterial blood vessels that are erased by the processing, the blood vessel lumen diameter d is accurately measured. The

  In addition, according to the vascular endothelial function testing device (vascular lumen diameter measuring device) 30 of the present embodiment, (a) the waveform of each waveform is obtained from the signal obtained by detecting the reflected signal SR including the two groups of reflected waves from the blood vessel 20. A peak time signal generating means 96 for generating a peak time signal SP indicated by a peak size and a time position of the peak; and (b) the lumen diameter calculating means 100 includes a blood vessel 20 in the peak time signal SP. Since the blood vessel lumen diameter d is calculated based on the interval between the two groups of peak time signal waveforms SW1 and SW2 corresponding to the two groups of waveforms due to reflection from the tube wall, the blood vessel lumen diameter d Is measured accurately. Since the peak time signal SP is indicated by the peak value of each waveform and the time position of the peak, the amount of data is reduced to a fraction of that of the sampled time-discrete reflected signal SR. The capacity of the memory and hard disk can be reduced, and the signal processing load is also reduced.

  Further, according to the vascular endothelial function testing device (vascular lumen diameter measuring device) 30 of the present embodiment, (a) the peak time signal waveform included in the two groups of peak time signal waveforms of the peak time signal SP. Measurement position determination means 98 for determining the measurement positions for measuring the interval between SW1 and SW2, respectively. (B) The lumen diameter calculation means 100 is a measurement position A1 determined by the measurement position determination means 98. Since the blood vessel lumen diameter d is calculated based on the distance between A2 and A2, the interval between the measurement positions included in the two groups of peak time signal waveforms SW1 and SW2 determined by the measurement position determination means 98 is calculated. Therefore, the blood vessel lumen diameter d is calculated more accurately.

  In addition, according to the vascular endothelial function testing device (vascular lumen diameter measuring device) 30 of the present embodiment, the measurement position determining means 98 includes two groups of peaks corresponding to the vessel wall of the blood vessel 20 in the peak time signal SP. As the interval between the time signal waveforms SW1 and SW2, the end point A1 and the second group of the small wave train located at the end of the first group of peak time signal waveforms SW1 of the two groups of peak time signal waveforms SW1 and SW2 are used. Since the start point A2 of the small wave train located at the beginning of the peak time signal waveform SW2 is determined as the measurement position, the lumen diameter calculating means 100 at the end of the peak time signal waveform SW1 of the first group. Since the vascular lumen diameter d is calculated based on the interval between the end point A1 of the positioned small wave train and the start point A2 of the small wave train located at the beginning of the peak time signal waveform SW2 of the second group, the vascular endothelium Considering vessel lumen diameter d is more accurately measured.

  Further, according to the vascular endothelial function testing device (vascular lumen diameter measuring device) 30 of the present embodiment, the waveform of the peak time signal SP is displayed on the image display device 34 by the display means 104, so the image display device 34. The vessel lumen diameter d can be viewed on the screen.

Further, according to the vascular endothelial function testing device (vascular lumen diameter measuring device) 30 of the present embodiment, an ultrasonic cross-sectional image that generates a cross-sectional image MG under the skin of the living body 14 based on the reflected signal SR from the artery 20. Generation means 92 is included, and the display means 104 causes the waveform of the peak time signal SP and the cross-sectional image MG to be parallel to the time axis of the waveform of the peak time signal SP and the depth direction of the cross-sectional image. Thus, the blood vessel lumen diameter d can be visually recognized on the image display device 34 in a state where the waveform of the peak time signal SP is compared with the ultrasonic cross-sectional image MG in parallel.

  Further, according to the vascular endothelial function testing device (vascular lumen diameter measuring device) 30 of the present embodiment, an ultrasonic cross-sectional image that generates a cross-sectional image MG under the skin of the living body 14 based on the reflected signal SR from the artery 20. Generation means 92 is included, and the display means 104 causes the waveform of the peak time signal SP and the cross-sectional image MG to be the end points A1 and A2 of the SP2 of the two groups of peak time signal waveforms SP1 included in the peak time signal SP. Are displayed on the image display device 34 so that the interval dimension of the tube and the lumen diameter d of the tube wall shown in the cross-sectional image MG have the same size and are positioned at the same position on the image display device. The interval between the two peak time signal waveforms SP1 and SP2 of the peak time signal SP is parallel with the same height and the same dimension as the lumen of the ultrasonic cross-sectional image MG. The lumen diameter d of the artery 20 can be more easily visible in the state of being.

  As mentioned above, although the Example of this invention was described in detail based on drawing, this invention can be applied also in another aspect.

  For example, in the above-described embodiment, the heart rate HR detected by the heart rate sensor 68a is used. However, the number of occurrences of the heart sound detected by the heart sound microphone per unit time and the artery detected by the pressure pulse wave sensor are used. Or the number of occurrences of pulse per unit time. Further, although the blood pressure value for each beat detected by the blood pressure sensor 68c is used as the biological information, the blood pressure value measured by the oscillometric method or the Korotkoff sound method using a cuff may be used.

  The biological information related to the autonomic nerve of the living body 14 includes not only the heart rate HR, the respiratory rate RR, the highest blood pressure value Psys and the lowest blood pressure value Pdia, the oxygen saturation level SpO2, and the electroencephalogram BW but also from them. It may be a calculated value. For example, the biological information in which the short period fluctuation component HF included in the fluctuation of the heart rate HR or the heartbeat period T, the long period fluctuation component LF around 10 seconds, or the ratio thereof (LF / HF) is related to the autonomic nerve of the living body 14. It is also possible to evaluate the autonomic nerve itself and use it together with% FMD for diagnosis.

  In addition, the above-described biological information measuring apparatus 68 measures the heart rate HR, the respiratory rate RR, the blood pressure BP, the oxygen saturation SpO2, and the brain wave BW of the living body 14 as biological information related to the autonomic nerve of the living body 14. However, what is necessary is just to measure at least one of them.

  In the above-described embodiment, the heart rate HR, the respiratory rate RR, the blood pressure BP, the oxygen saturation SpO2, and the brain wave BW of the living body 14 are displayed on the image display device 34 by the display unit 104 as a trend graph as shown in FIG. However, the average value of the biological information measured in the rest period A may be displayed on a radar chart having a plurality of axes radially indicating values of a plurality of types of biological information.

  Further, in the vascular endothelial function testing device (vascular lumen diameter measuring device) 30 of the above-described embodiment, the inside of the artery 20 is based on the interval between the two groups of peak time signal waveforms SW1 and SW2 obtained from the reflected signal SR. Although the cavity diameter d has been measured, for example, the lumen diameter d may be measured from the image of the artery 20 in the ultrasonic cross-sectional image MG shown in FIG.

  In the vascular endothelial function testing device (vascular lumen diameter measuring device) 30 of the above-described embodiment, the artery 20 is blocked by compression with the cuff 88 and then the pressure is released to resume blood flow in the artery 20. Thus, stimulation as a shearing stress is given to the endothelial cells of the artery 20, but it may be stimulation to the artery 20 by temperature and medicine. The stimulation of the artery 20 due to the above temperature is the same as the so-called cold presser test in which water is placed at 4 ° C., thereby enhancing the sympathetic nerve and changing the blood flow, and applying shear stress to the endothelial cells. Is physically stimulating. In addition, stimulation of the artery 20 by the above-mentioned drug is to administer nitroglycerin sublingually or by spraying to act (stimulate) NO (nitro) on vascular smooth muscles to relax the blood vessels. In this case,% NMD [= 100 × (dmax−d) / d] (where d is the vascular lumen diameter at rest before nitro administration, and dmax is the maximum vascular lumen diameter after nitro administration) is evaluated. Used as a value.

  Further, in the vascular endothelial function testing device 30 of the above-described embodiment, the artery 20 is blocked by the forearm being compressed by the cuff 88, but other parts of the living body 14, such as the upper arm or ankle, may be compressed.

  Further, in the vascular endothelial function testing device 30 of the above-described embodiment, the display of the biological information shown in FIG. 9 is displayed on the image display device 34 provided therein, but is separate from the vascular endothelial function testing device 30. The biological information measuring device 68 may be displayed, or the biological information and the blood vessel lumen diameter d and% FMD may be separately displayed on different screens.

  Further, in the above-described embodiment, the sensor holding device 10 including the two link mechanisms 48 and 50 is used to hold the ultrasonic probe 12. However, other sensors including an extendable arm, a robot arm, and the like are used. A sensor holding device having a configuration may be used, and the ultrasonic probe 12 may be directly attached to the upper arm or the like of the living body 14 by an arm band or the like. The ultrasonic probe 12 may be used while being held by an operator's hand.

  The above description is only an embodiment, and the present invention can be implemented in variously modified and improved forms based on the knowledge of those skilled in the art.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which illustrates roughly the structure of the vascular endothelial function test | inspection apparatus of one Example of this invention. It is a figure which expands and demonstrates the structure of the universal joint and stopper apparatus which hold | maintain an ultrasonic array in the front-end | tip part of the sensor holding apparatus of FIG. FIG. 2 is a diagram showing in detail an electrical configuration including an ultrasonic array, an ultrasonic drive control circuit, and an electronic control device provided at the tip of the ultrasonic probe in the embodiment of FIG. 1. It is a functional block diagram explaining the principal part of the control function of the electronic control apparatus of FIG. It is a figure which shows a part of reflected signal detected by the reflected signal detection means of FIG. It is a figure which shows a part of reflected signal detected by the detection means of FIG. It is a figure which shows a part of peak time signal produced | generated by the peak time signal production | generation means of FIG. It is a figure which shows the parallel display example of the ultrasonic cross-sectional image MG of biometric information by the display means of FIG. 3, and the peak time signal SP. It is a figure which shows the example of a display of the biometric information by the display means of FIG.

Explanation of symbols

14: Living body 20: Arteries (blood vessels)
30: Vascular endothelial function testing device (luminal diameter measuring device)
34: Image display device (display)
68: Biological information measuring device 104: Display means

Claims (6)

In order to obtain the rate of change of the lumen diameter of a blood vessel, a blood vessel lumen diameter measuring device that repeatedly measures the lumen diameter of the blood vessel of the living body after giving a stimulus to the living body,

An indicator,
A biological information measuring device for measuring biological information generated from the living body in relation to the activity of the autonomic nerve of the living body;
A blood vessel lumen diameter measuring device comprising: display means for causing the display to display and output biological information measured by the biological information measuring device at least during a rest period provided before the stimulation. The biological information measuring device repeatedly measures the biological information in the rest period,
2. The blood vessel lumen diameter measuring device according to claim 1, wherein the display means displays the biological information repeatedly measured in the rest period on the display in time series. The indicator displays two-dimensional coordinates having a time axis including the rest period and the period after the stimulus is released,
The lumen diameter is repeatedly measured in the period after the release of the stimulus,
3. The blood vessel lumen diameter measuring device according to claim 1, wherein the display means displays the lumen diameter or a rate of change thereof and the biological information in a graph along the time axis. 4. The biological information measuring device measures at least one of heart rate, respiratory rate, blood pressure, body temperature, and electroencephalogram of the living body as the biological information. Blood vessel lumen diameter measuring device. The stimulation to the blood vessel is performed by compressing a part of the living body and blocking a blood vessel continuous in the part of the living body within a predetermined ischemic period, and then releasing the pressure to resume blood flow in the blood vessel. The blood vessel lumen diameter measuring device according to any one of claims 1 to 4, wherein the device is a shear stress applied to the endothelial cells of the blood vessel. The rest period on the time axis is set so that the time per unit length is longer with respect to the ischemic period, and the time per unit length is shorter than the period after the ischemia is released. The blood vessel lumen diameter measuring device according to claim 5.

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