Ultrasonic diagnostic device, control method of ultrasonic diagnostic device, and processor for ultrasonic diagnostic device

Abstract

An ultrasonic diagnostic apparatus (1) comprises: a first blood vessel wall detection unit (10) for analyzing a B-mode image including a short-axis image of a blood vessel to detect the blood vessel wall in the short-axis direction; a first blood vessel diameter calculation unit (11) for calculating a first blood vessel diameter based on the blood vessel wall in the short-axis direction; a second blood vessel wall detection unit (12) for analyzing a B-mode image including a long-axis image of a blood vessel to detect the blood vessel wall in the long-axis direction; a second blood vessel diameter calculation unit (13) for calculating a second blood vessel diameter based on the blood vessel wall in the long-axis direction; a blood flow velocity calculation unit (15) for calculating the blood flow velocity based on Doppler data within a Doppler gate set on the B-mode image; and a blood flow measurement unit (16) for measuring the blood flow based on the blood vessel wall and the blood flow velocity in the long-axis direction or the short-axis direction, and automatically measuring the blood flow when the second blood vessel diameter is within a range determined relative to the first blood vessel diameter.

Description

Technical Field

[0001] The present invention relates to an ultrasonic diagnostic device for acquiring B-mode data and Doppler data, a control method for the ultrasonic diagnostic device, and a processor for the ultrasonic diagnostic device. Background Art

[0002] As a device for obtaining an image of the inside of a subject, an ultrasonic diagnostic device is known. The ultrasonic diagnostic device generally includes an ultrasonic probe having a transducer array formed by arranging a plurality of elements. When the ultrasonic probe is in contact with the body surface of the subject, an ultrasonic beam is emitted from the transducer array toward the inside of the subject, and the transducer array receives ultrasonic echoes from the subject to obtain element data. Furthermore, the ultrasonic diagnostic device electrically processes the obtained element data to generate an ultrasonic image of the part of the subject.

[0003] For example, Patent Document 1 discloses an ultrasonic diagnostic device that, when an ultrasonic image including a long-axis image of a subject's blood vessels is displayed on a display device, measures the blood flow in a designated vascular area triggered by a user specifying a vascular area on the ultrasonic image displayed on the display device.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: International Publication No. 2019-187649 Summary of the invention

[0007] Technical issues to be solved by the invention

[0008] Here, in order to accurately measure the blood flow, it is expected that the long-axis image of the blood vessel included in the ultrasonic image corresponds to the longitudinal section of the blood vessel where the longitudinal section of the blood vessel passing through the center of the blood vessel (i.e., the measured blood vessel diameter) becomes the largest. However, in Patent Document 1, since the ultrasonic image including the long-axis image of the blood vessel is acquired after the position of the ultrasonic probe is determined based on judgment based on the user's experience, etc., it is sometimes impossible to obtain an ultrasonic image including the long-axis image of the appropriate blood vessel. In addition, in the invention of Patent Document 1, in order to measure the blood flow, the user needs to specify the blood vessel area, so there is still room for improvement in terms of simplifying the measurement.

[0009] The present invention has been made to solve such conventional problems, and an object of the present invention is to provide an ultrasonic diagnostic apparatus capable of easily performing measurement while improving the measurement accuracy of blood flow.

[0010] Means for solving technical problems

[0011] In order to achieve the above-mentioned object, the ultrasonic diagnostic apparatus according to the present invention is characterized in that it comprises: a transducer array for acquiring a received signal by transmitting and receiving ultrasonic waves to a subject; a B-mode processing unit for generating a B-mode image of at least a captured blood vessel based on the received signal; a display device for displaying the B-mode image generated by the B-mode processing unit; a first blood vessel wall detection unit for detecting a blood vessel wall in a short-axis direction by analyzing a B-mode image of a captured short-axis image of a blood vessel; a first blood vessel diameter calculation unit for calculating a first blood vessel diameter based on the blood vessel wall in the short-axis direction detected by the first blood vessel wall detection unit; and a second blood vessel wall detection unit for detecting a blood vessel in a long-axis direction by analyzing a B-mode image of a captured long-axis image of a blood vessel. a second blood vessel diameter calculation unit that calculates a second blood vessel diameter based on the blood vessel wall in the long-axis direction detected by the second blood vessel wall detection unit; a gate setting unit that sets a Doppler gate in the blood vessel on the B-mode image in which the long-axis image is captured; a Doppler processing unit that acquires Doppler data in the Doppler gate; a blood flow velocity calculation unit that calculates the blood flow velocity based on the Doppler data; and a blood flow measurement unit that measures the blood flow based on any one of the detected blood vessel wall in the long-axis direction and the blood vessel wall in the short-axis direction and the calculated blood flow velocity, and automatically measures the blood flow when the second blood vessel diameter calculated by the second blood vessel diameter calculation unit is within a range determined relative to the first blood vessel diameter calculated by the first blood vessel diameter calculation unit.

[0012] The second vascular wall detection unit may set a search line for searching for the vascular wall in the longitudinal direction on the B-mode image, and detect the anterior vascular wall and the posterior vascular wall as the vascular wall in the longitudinal direction based on the brightness distribution of the B-mode image on the set search line.

[0013] In this case, the second vascular wall detection unit may set detection point marks on the detected anterior vascular wall and posterior vascular wall, respectively, and display them on the display device.

[0014] Furthermore, the gate setting unit may set the Doppler gate having a center position and a size determined based on the coordinates of the anterior blood vessel wall and the posterior blood vessel wall detected by the second blood vessel wall detection unit.

[0015] Furthermore, the second vascular wall detection unit may estimate the blood vessel running angle based on at least one of the detected anterior blood vessel wall and posterior blood vessel wall, and set the Doppler deflection angle so that the angle correction value with respect to the blood vessel running angle is within 60 degrees.

[0016] In this case, the B-mode processing unit may generate a B-mode image based on a B-mode deflection angle that is set based on the blood vessel running angle estimated by the second blood vessel wall detection unit.

[0017] Furthermore, the Doppler processing unit may generate a Doppler waveform image based on the Doppler data, and the display device may display both the B-mode image generated by the B-mode processing unit and the Doppler waveform image generated by the Doppler processing unit.

[0018] Furthermore, the Doppler processing unit generates a Doppler waveform image in parallel with the B-mode processing unit generating the B-mode image, and the blood flow measurement unit measures the blood flow after both the B-mode image and the Doppler waveform image are frozen.

[0019] Alternatively, the Doppler processing unit acquires Doppler data within the Doppler gate to generate a Doppler waveform image after the B-mode image is frozen, and the blood flow measurement unit measures the blood flow after the Doppler waveform image is frozen.

[0020] Furthermore, the blood flow rate may be automatically measured when the second blood vessel diameter calculated over a predetermined number of frames is maintained within a range determined with respect to the calculated first blood vessel diameter.

[0021] The control method of the ultrasonic diagnostic apparatus according to the present invention is characterized in that it includes the steps of: generating a B-mode image in which at least a blood vessel is imaged based on a reception signal obtained by transmitting and receiving ultrasonic waves to a subject; displaying the B-mode image; detecting a blood vessel wall in a short-axis direction by analyzing a short-axis image of the blood vessel imaged in the B-mode image; calculating a first blood vessel diameter based on the detected blood vessel wall in the short-axis direction; detecting a blood vessel wall in a long-axis direction by analyzing a B-mode image in which a long-axis image of the blood vessel is imaged; calculating a second blood vessel diameter based on the detected blood vessel wall in the long-axis direction; setting a Doppler gate in the blood vessel on the B-mode image in which the long-axis image is imaged when the calculated second blood vessel diameter is within a predetermined range with respect to the calculated first blood vessel diameter; acquiring Doppler data in the Doppler gate; calculating a blood flow velocity based on the Doppler data; and measuring a blood flow volume based on either the detected blood vessel wall in the long-axis direction or the detected blood vessel wall in the short-axis direction and the calculated blood flow velocity.

[0022] The processor for ultrasonic diagnostic apparatus according to the present invention is characterized in that the processor performs the following processing: generating a B-mode image in which at least a blood vessel is imaged based on a reception signal obtained by transmitting and receiving ultrasonic waves to a subject; displaying the B-mode image; detecting a blood vessel wall in a short-axis direction by analyzing a short-axis image of the blood vessel imaged in the B-mode image; calculating a first blood vessel diameter based on the detected blood vessel wall in the short-axis direction; detecting a blood vessel wall in a long-axis direction by analyzing a B-mode image in which a long-axis image of the blood vessel is imaged; calculating a second blood vessel diameter based on the detected blood vessel wall in the long-axis direction; setting a Doppler gate in the blood vessel on the B-mode image in which the long-axis image is imaged when the calculated second blood vessel diameter is within a range determined with respect to the calculated first blood vessel diameter; acquiring Doppler data in the Doppler gate; calculating a blood flow velocity based on the Doppler data; and measuring a blood flow volume based on either the detected blood vessel wall in the long-axis direction or the detected blood vessel wall in the short-axis direction and the calculated blood flow velocity.

[0023] Effects of the Invention

[0024] According to the present invention, the present invention comprises: a first blood vessel wall detection unit for detecting the blood vessel wall in the short-axis direction by analyzing a B-mode image in which a short-axis image of the blood vessel is captured; a first blood vessel diameter calculation unit for calculating a first blood vessel diameter based on the blood vessel wall in the short-axis direction; a second blood vessel wall detection unit for detecting the blood vessel wall in the long-axis direction by analyzing a B-mode image in which a long-axis image of the blood vessel is captured; a second blood vessel diameter calculation unit for calculating a second blood vessel diameter based on the blood vessel wall in the long-axis direction; and a gate setting unit for setting a doppler gate in the blood vessel on the B-mode image in which the long-axis image is captured. a Doppler gate; a Doppler processing unit that acquires Doppler data within the Doppler gate; a blood flow velocity calculation unit that calculates the blood flow velocity based on the Doppler data; and a blood flow measurement unit that measures the blood flow based on either the blood vessel wall in the long-axis direction or the blood vessel wall in the short-axis direction and the blood flow velocity, and automatically measures the blood flow when the second blood vessel diameter calculated by the second blood vessel diameter calculation unit is within a range determined relative to the first blood vessel diameter calculated by the first blood vessel diameter calculation unit, thereby enabling simple measurement while improving the measurement accuracy of the blood flow. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a block diagram showing the configuration of an ultrasonic diagnostic apparatus according to the first embodiment of the present invention.

[0026] Figure 2 This is a block diagram showing the internal structure of the receiving circuit in the first embodiment of the present invention.

[0027] Figure 3 This is a block diagram showing the internal structure of the B-mode processing unit in the first embodiment of the present invention.

[0028] Figure 4 FIG. 1 is a diagram schematically showing an example of a B-mode image showing a short-axis image of a blood vessel.

[0029] Figure 5 This is a diagram schematically showing an example of the brightness distribution of an image on a straight line crossing the short-axis image of a blood vessel.

[0030] Figure 6 FIG. 1 is a diagram schematically showing an example of a B-mode image showing a long-axis image of a blood vessel.

[0031] Figure 7 This is a diagram schematically showing an example of the brightness distribution of an image on a straight line crossing the long-axis image of a blood vessel.

[0032] Figure 8 FIG. 2 is a diagram schematically showing the estimated propagation angle of a blood vessel on a B-mode image.

[0033] Fig. 9 It is a diagram schematically showing a method of setting the B-mode deflection angle in the first embodiment of the present invention.

[0034] Fig.10 It is a diagram schematically showing a method of setting a Doppler deflection angle in the first embodiment of the present invention.

[0035] Fig.11 This is a graph showing the relationship between the angle between the ultrasonic beam and the blood flow and the estimation error of the blood flow velocity.

[0036] Fig.12 It is a diagram schematically showing a B-mode image displayed on a display device and a Doppler gate set on the B-mode image in the first embodiment of the present invention.

[0037] Fig.13 This is a block diagram showing the internal structure of the Doppler processing unit in the first embodiment of the present invention.

[0038] Fig.14 This is a flowchart showing the operation of the ultrasonic diagnostic apparatus according to the first embodiment of the present invention.

[0039] Fig.15 It is a diagram schematically showing a B-mode image and a Doppler waveform image displayed on a display device in the first embodiment of the present invention.

[0040] Fig.16 This is a flowchart showing the operation of automatic blood flow measurement in the first embodiment of the present invention.

[0041] Fig.17It is a diagram schematically showing a B-mode image, a Doppler waveform image, and a measured value of a blood flow rate displayed on a display device in the first embodiment of the present invention.

[0042] Fig.18 FIG. 2 is a diagram schematically showing measurement point marks arranged on a short-axis image of a blood vessel.

[0043] Fig.19 FIG. 1 is a diagram schematically showing measurement point marks arranged on a long-axis image of a blood vessel.

[0044] Fig. 20 This is a flowchart showing the operation of the ultrasonic diagnostic apparatus according to the second embodiment of the present invention.

[0045] Fig.21 This is a block diagram schematically showing the temporal change of the blood vessel diameter in the second embodiment of the present invention.

[0046] Fig. 22 This is a block diagram showing the configuration of an ultrasonic diagnostic apparatus according to a third embodiment of the present invention. DETAILED DESCRIPTION

[0047] Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[0048] The description of the constituent elements described below is based on typical embodiments of the present invention, but the present invention is not limited to these embodiments.

[0049] In addition, in this specification, the numerical range expressed using "to" means a range including the numerical values ​​described before and after "to" as the lower limit and the upper limit.

[0050] Furthermore, in this specification, "perpendicular" and "parallel" include the error range allowed in the technical field to which the present invention belongs. For example, "perpendicular" and "parallel" mean that the error is within a range of less than ±10 degrees relative to the vertical or parallel in the strict sense, and the error relative to the vertical or parallel in the strict sense is preferably less than 5 degrees, and more preferably less than 3 degrees.

[0051] In this specification, "same" or "identical" includes the error range generally allowed in the technical field. In addition, in this specification, when "all", "all" or "entire surface" is recorded, in addition to 100%, it also includes the error range generally allowed in the technical field, such as 99% or more, 95% or more, or 90% or more.

[0052] First Embodiment

[0053] Figure 1 FIG. 2 shows a structure of an ultrasonic diagnostic apparatus 1 according to a first embodiment of the present invention. Figure 1As shown, the ultrasonic diagnostic apparatus 1 includes a transducer array 2, and a transmitting circuit 3 and a receiving circuit 4 are connected to the transducer array 2. Here, the transmitting circuit 3 and the receiving circuit 4 constitute a transceiver circuit 5. The receiving circuit 4 is connected to a B-mode (Brightness mode) processing unit 6 and a Doppler processing unit 7, and the B-mode processing unit 6 and the Doppler processing unit 7 are connected to a display device 9 via a display control unit 8.

[0054] Furthermore, the first blood vessel wall detection unit 10 is connected to the B-mode processing unit 6, and the first blood vessel diameter calculation unit 11 is connected to the first blood vessel wall detection unit 10. Furthermore, the second blood vessel wall detection unit 12 is connected to the B-mode processing unit 6, and the second blood vessel diameter calculation unit 13 and the gate setting unit 14 are connected to the second blood vessel wall detection unit 12. The gate setting unit 14 is connected to the Doppler processing unit 7. Furthermore, the blood flow velocity calculation unit 15 is connected to the Doppler processing unit 7. Furthermore, the first blood vessel diameter calculation unit 11, the second blood vessel diameter calculation unit 13, and the blood flow velocity calculation unit 15 are connected to the blood flow measurement unit 16. Furthermore, the first blood vessel wall detection unit 10, the first blood vessel diameter calculation unit 11, the second blood vessel wall detection unit 12, the second blood vessel diameter calculation unit 13, the gate setting unit 14, and the blood flow measurement unit 16 are connected to the display control unit 8.

[0055] Furthermore, a device control unit 17 is connected to the transceiver circuit 5, the B-mode processing unit 6, the Doppler processing unit 7, the display control unit 8, the first blood vessel wall detection unit 10, the first blood vessel diameter calculation unit 11, the second blood vessel wall detection unit 12, the second blood vessel diameter calculation unit 13, the gate setting unit 14, the blood flow velocity calculation unit 15, and the blood flow measurement unit 16. Furthermore, an input device 18 and a storage unit 19 are connected to the device control unit 17. The device control unit 17 and the storage unit 19 are connected to each other so as to be able to exchange information bidirectionally.

[0056] The transducer array 2 is included in the ultrasonic probe 21. The B-mode processing unit 6, the Doppler processing unit 7, the display control unit 8, the first blood vessel wall detection unit 10, the first blood vessel diameter calculation unit 11, the second blood vessel wall detection unit 12, the second blood vessel diameter calculation unit 13, the gate setting unit 14, the blood flow velocity calculation unit 15, and the blood flow measurement unit 16 constitute a processor 22 for the ultrasonic diagnostic apparatus 1.

[0057] Figure 1The transducer array 2 of the ultrasonic probe 21 shown has a plurality of transducers arranged in one dimension or two dimensions. These transducers transmit ultrasonic waves according to the driving signal supplied from the transmitting circuit 3, respectively, and receive ultrasonic echoes from the subject to output signals based on the ultrasonic echoes. Each transducer is constituted by forming electrodes at both ends of a piezoelectric body including, for example, a piezoelectric ceramic represented by PZT (Lead Zirconate Titanate), a polymer piezoelectric element represented by PVDF (Poly Vinylidene Di Fluoride), and a piezoelectric single crystal represented by PMN-PT (Lead Magnesium Niobate-Lead Titanate).

[0058] The transmitting circuit 3 includes, for example, a plurality of pulse generators, and supplies respective drive signals to the plurality of transducers by adjusting the delay amount according to a transmission delay pattern selected according to a control signal from the device control unit 17, so that the ultrasonic waves transmitted from the plurality of transducers of the transducer array 2 form an ultrasonic beam. In this way, when a pulsed or continuous wave voltage is applied to the electrodes of the transducers of the transducer array 2, the piezoelectric body expands and contracts, and a pulsed or continuous wave ultrasonic wave is generated from each transducer, and an ultrasonic beam is formed by the synthetic wave of these ultrasonic waves.

[0059] The transmitted ultrasonic beam is reflected at an object such as a part of a subject, and propagates toward the transducer array 2 of the ultrasonic probe 21. The ultrasonic wave thus propagated toward the transducer array 2 is received by each transducer constituting the transducer array 2. At this time, each transducer constituting the transducer array 2 expands and contracts by receiving the propagated ultrasonic echo, thereby generating electrical signals, and outputs the electrical signals to the receiving circuit 4.

[0060] The receiving circuit 4 processes the signal output from the transducer array 2 according to the control signal from the device control unit 17, thereby generating so-called RF (Radio Frequency) data, that is, received data. Figure 2 As shown, the receiving circuit 4 has a structure in which an amplifier 23, an AD (Analog Digital) converter 24, and a beam former 25 are connected in series.

[0061] The amplifier 23 amplifies the signal input from each transducer constituting the transducer array 2, and sends the amplified signal to the AD converter 24. The AD converter 24 converts the signal sent from the amplifier 23 into digital data, and sends the data to the beamformer 25. The beamformer 25 performs so-called reception focusing processing by providing each data converted by the AD converter 24 with respective delays according to the sound velocity or the distribution of the sound velocity, which is set according to the reception delay mode selected according to the control signal from the device control unit 17, and adding them. Through this reception focusing processing, reception data obtained by phasing and adding each data converted by the AD converter 24 and narrowing the focus of the ultrasonic echo is acquired.

[0062] like Figure 3 As shown, the B-mode processing unit 6 has a structure in which a signal processing unit 26, a DSC (Digital Scan Converter) 27, and an image processing unit 28 are sequentially connected in series.

[0063] The signal processing unit 26 corrects the attenuation due to distance according to the depth of the ultrasonic reflection position of the reception data generated by the reception circuit 4 and then performs envelope detection processing to generate a B-mode image signal which is tomographic image information related to the tissue in the subject.

[0064] The DSC 27 converts (raster converts) the B-mode image signal generated by the signal processing unit 26 into an image signal conforming to a scanning method of a normal television signal.

[0065] Image processing unit 28 performs various necessary image processing such as grayscale processing on the B-mode image signal input from DSC 27, and then outputs the B-mode image signal to display control unit 8. Hereinafter, the B-mode image signal subjected to the image processing by image processing unit 28 is simply referred to as a B-mode image.

[0066] When the B-mode image generated by the B-mode processing unit 6 includes a short-axis image of a blood vessel of the subject, the first blood vessel wall detection unit 10 detects the blood vessel wall in the short-axis direction by analyzing the short-axis image of the blood vessel captured in the B-mode image. Here, the short-axis image of the blood vessel refers to a cross section of the blood vessel along a direction orthogonal to the traveling direction of the blood vessel.

[0067] When detecting the vessel wall in the short axis direction, e.g. Figure 4As shown in FIG. 1 , the first blood vessel wall detection unit 10 sets a search region R1 of the blood vessel B in the central portion of the azimuth direction D2 that is orthogonal to the depth direction D1 of the B-mode image UB, and detects the brightness on the search line SL1 while scanning a virtual search line SL1 extending along the depth direction D1 of the B-mode image UB along the lateral direction D2 within the set search region R1, so as to generate a brightness distribution of an image along the search line SL1 within the search region R1. For example, Figure 5 As shown, the brightness distribution of the image represents the relationship between the depth in the B-mode image UB and the brightness of the image on the search line SL1. Figure 5 In the example shown, depth is plotted on the horizontal axis and brightness is plotted on the vertical axis.

[0068] in addition, Figure 4 In FIG. 1 , as examples of the search line SL1 , a dotted search line SL1 passing through a position relatively far from the center of the blood vessel B on the short-axis image of the blood vessel B and a solid search line SL1 passing through the vicinity of the center of the blood vessel B are shown. Figure 5 , as an example of brightness distribution, a dotted line graph G1 corresponding to the dotted line search line SL1 and a solid line graph G2 corresponding to the solid line search line SL1 are shown.

[0069] Here, the brightness change of the image on the search line SL1 passing through the short-axis image of the blood vessel B is greater at the two points X1 and X2 corresponding to the blood vessel wall than at other points on the search line SL1. Figure 5 In the brightness distribution of , two depths J1 and J2 at which the brightness value becomes the maximum value greater than the constant brightness threshold value K1 correspond to the two points X1 and X2 corresponding to the blood vessel wall. Furthermore, when the search line SL1 is scanned along the horizontal direction D2 on the short-axis image of the approximately circular blood vessel B, the value of the difference L1 between the depth J1 and the depth J2 in the brightness distribution increases from zero to a maximum value corresponding to the diameter of the blood vessel B as the search line SL1 is scanned from one end to the other end on the horizontal direction D2 of the short-axis image of the blood vessel B, and then decreases to zero. In this way, the value of the difference L1 calculated while scanning the search line SL1 along the horizontal direction D2 on the short-axis image of the blood vessel B changes so as to have a maximum value.

[0070] Therefore, the first vascular wall detection unit 10 can determine whether the short-axis image of the blood vessel is included in the B-mode image UB based on the brightness distribution generated while scanning the search line SL1 along the horizontal direction D2. For example, when the difference L1 between the depth J1 and the depth J2 in the brightness distribution is calculated while scanning the search line SL1 along the horizontal direction D2, and the value of the calculated difference L1 changes so as to have a maximum value, the first vascular wall detection unit 10 can recognize that the short-axis image of the blood vessel B exists in the search area R1 of the B-mode image UB. In this case, the first vascular wall detection unit 10 detects the locus of the points X1 and X2 corresponding to the depths J1 and J2 where the brightness value in the brightness distribution becomes maximum as the vascular wall. In addition, the first vascular wall detection unit 10 detects the information of the positions of the points X1M and X2M corresponding to the depths J1M and J2M where the difference L1 calculated while scanning the search line SL1 along the horizontal direction D2 becomes the maximum value L1M, and sends it to the first vascular diameter calculation unit 11. The points X1M and X2M correspond to intersections of the search line SL1 passing through the center of the blood vessel B and the contour line of the short-axis image of the blood vessel B.

[0071] The first blood vessel diameter calculation unit 11 calculates a first blood vessel diameter corresponding to the diameter of the blood vessel B based on the information on the positions of the points X1M and X2M on the blood vessel wall received from the first blood vessel wall detection unit 10. Figure 4 As shown, the first blood vessel diameter calculation unit 11 may display the calculated first blood vessel diameter DF on the display device 9 , for example.

[0072] The second blood vessel wall detection unit 12 detects the blood vessel wall in the long-axis direction by analyzing the B-mode image UB generated based on the first blood vessel diameter DF calculated by the first blood vessel diameter calculation unit 11 and capturing the long-axis image of the blood vessel B. Here, the long-axis image of the blood vessel B refers to a longitudinal section of the blood vessel B along the direction in which the blood vessel B runs.

[0073] When detecting the vessel wall in the long axis direction, e.g. Figure 6 As shown in FIG. 1 , the second vascular wall detection unit 12 sets a search area R2 in the central portion of the B-mode image UB in the horizontal direction D2, and detects the brightness on the search line SL2 while scanning a virtual search line SL2 extending in the depth direction D1 in the horizontal direction D2 within the set search area R2, so as to generate a virtual search line SL2 as shown in FIG. Figure 7 The brightness distribution of the image along the search line SL2 is shown.

[0074] in addition, Figure 6 In FIG. 1 , as examples of the search line SL2, a dotted search line SL2 and a solid search line SL2 arranged at a position different from the search line SL2 are shown. Figure 7, as an example of a graph of brightness distribution, a dotted line graph G3 corresponding to the dotted line search line SL2 and a solid line graph G4 corresponding to the solid line search line SL2 are shown. The graphs G3 and G4 are offset from each other in a direction parallel to the horizontal axis, but the depth differences between the two points where the brightness becomes maximum are almost the same.

[0075] Here, similarly to the brightness change of the image on the search line SL1 passing through the short-axis image of the blood vessel B, the brightness change of the image on the search line SL2 passing through the long-axis image of the blood vessel B is greater at two points X3 and X4 corresponding to the blood vessel wall than at other points on the search line SL2. Figure 7 In the brightness distribution of , two depths J3 and J4 where the brightness value becomes the maximum value greater than the constant brightness threshold value K2 correspond to two points X3 and X4 corresponding to the blood vessel wall. Figure 6 As shown, when the search line SL2 is scanned along the horizontal direction D2 on the long-axis image of the tubular blood vessel B extending roughly along the horizontal direction D2, ideally, even if the search line SL2 is scanned along the horizontal direction D2, the difference L2 between the depth J3 and the depth J4 in the brightness distribution hardly changes, and even if it changes, the range of change is very small.

[0076] Therefore, the second vascular wall detection unit 12 can determine whether the long-axis image of the blood vessel B is included in the B-mode image UB based on the brightness distribution generated while scanning the search line SL2 along the horizontal direction D2. For example, when the difference L2 between the depth J3 and the depth J4 in the brightness distribution is calculated while scanning the search line SL2 along the horizontal direction D2, and the calculated difference L2 has a substantially constant value, the second vascular wall detection unit 12 can determine that the long-axis image of the blood vessel B exists in the search region R2 of the B-mode image UB. Here, the substantially constant value of the difference L2 means, for example, that the difference between the maximum value and the minimum value of the difference L2 is equal to or less than a predetermined value.

[0077] The second vascular wall detection unit 12 detects the position of the relatively shallow depth J3 of the depths J3 and J4 where the brightness value detected in this way becomes the maximum value as the position of the vascular anterior wall W1, and detects the position of the relatively deep depth J4 as the position of the vascular posterior wall W2. The second vascular wall detection unit 12 transmits information on the detected positions of the vascular anterior wall W1 and the vascular posterior wall W2 to the second vascular diameter calculation unit 13.

[0078] The second blood vessel diameter calculation unit 13 calculates the second blood vessel diameter of the blood vessel B based on the information on the positions of the blood vessel anterior wall W1 and the blood vessel posterior wall W2 detected by the second blood vessel wall detection unit 12. For example, the second blood vessel diameter calculation unit 13 calculates the maximum distance in the depth direction D1 between the blood vessel anterior wall W1 and the blood vessel posterior wall W2 as the second blood vessel diameter. Figure 6As shown, the second blood vessel wall detection unit 12 displays the calculated second blood vessel diameter DS on the display device 9 .

[0079] Then, the second blood vessel diameter calculation unit 13 compares the calculated second blood vessel diameter DS with the first blood vessel diameter DF calculated by the first blood vessel diameter calculation unit 11 to determine whether the second blood vessel diameter DS has a value within a predetermined range including the first blood vessel diameter DF. When it is determined that the second blood vessel diameter DS has a value within the predetermined range, the second blood vessel diameter calculation unit 13 determines that a B-mode image UB including a long-axis image of the blood vessel B representing a longitudinal section passing through the center of the blood vessel B has been obtained, and transmits the value of the second blood vessel diameter DS within the predetermined range to the blood flow measurement unit 16.

[0080] Furthermore, the second vascular wall detection unit 12 estimates the angle of the blood vessel in the B-mode image UB. For example, the second vascular wall detection unit 12 can estimate the inclination of the blood vessel B by estimating a straight line passing through a plurality of positions on the detected vascular anterior wall W1 and a straight line passing through a plurality of positions on the detected vascular posterior wall W2, and averaging the inclinations of the estimated two straight lines. Figure 6 In the example shown, a virtual blood vessel gradient line BL is obtained that indicates the gradient of the blood vessel B. Furthermore, the second blood vessel wall detection unit 12 may estimate the inclination of the blood vessel B based on any one of a straight line passing through a plurality of positions on the detected blood vessel anterior wall W1 or a straight line passing through a plurality of positions on the detected blood vessel posterior wall W2.

[0081] And, for example, Figure 8 As shown, the second vascular wall detection unit 12 can estimate the angle between the obtained vascular gradient line BL and a virtual straight line AL along the depth direction D1 of the B-mode image UB as the vascular running angle BA.

[0082] Then, the second vascular wall detection unit 12 sets the B-mode deflection angle using the estimated vascular running angle BA. Fig. 9 As shown in FIG. 1 , the angle A1 and the like are set as the B-mode deflection angle. The B-mode deflection angle is defined as the angle between the scanning line when the B-mode processing unit 6 generates the B-mode image UB and the straight line AL along the depth direction D1 in the B-mode image UB. Here, in order to obtain a B-mode image UB that clearly shows the anterior vascular wall W1 and the posterior vascular wall W2, the second vascular wall detection unit 12 sets the B-mode deflection angle so that the angle between the scanning line when generating the B-mode image UB and the vascular gradient line BL is close to 90 degrees.

[0083] For example, the second vascular wall detection unit 12 can use the vascular advancing angle BA, the predetermined angle A1, and the predetermined angle A2 greater than the angle A1, and when the relationship 90-BA<A1 / 2 is satisfied, the B-mode deflection angle is set to 0 degrees, and when the relationship A1 / 2≤90-BA<A2 / 2 is satisfied, the B-mode deflection angle is set to 0 degrees. Fig. 9 As shown, the B-mode deflection angle is set to angle A1, and when the relationship A2 / 2≤90-BA is satisfied, the B-mode deflection angle is set to angle A2. Here, for example, angle A1 can be preset to 7.5 degrees, and angle A2 can be preset to 15 degrees.

[0084] Then, the second vascular wall detection unit 12 sets the Doppler deflection angle using the estimated vascular running angle BA. Fig.10 As shown in FIG. 1 , angle B1 or angle B2 is set as the Doppler deflection angle. Here, the Doppler deflection angle refers to the inclination of the scanning line when acquiring Doppler data.

[0085] Here, it is known that there is a certain difference between the angle H between the ultrasonic beam emitted into the blood vessel B to obtain Doppler data and the blood flow in the blood vessel B and the estimated error E of the blood flow velocity calculated based on the obtained Doppler data. Fig.11 According to this relationship, the larger the angle H of the ultrasonic beam relative to the blood flow, the larger the estimated error E of the blood flow velocity exponentially becomes. Also, the larger the error of the angle correction relative to the angle of the blood vessel, the larger the estimated error E of the blood flow velocity becomes.

[0086] In addition, regarding the angle H between the ultrasonic beam and the blood flow and the estimation error E of the blood flow velocity, it is known that, for example, as long as the angle H between the ultrasonic beam and the blood flow is maintained within 60 degrees, even if there is an error of 3 degrees in the angle correction relative to the blood vessel advancing angle, the estimation error E of the blood flow velocity will fall within 10%, and the blood flow velocity can be accurately obtained. Here, in order to accurately calculate the blood flow velocity, the second blood vessel wall detection unit 12 sets the Doppler deflection angle so that the angle correction value relative to the blood vessel advancing angle BA, that is, the angle between the scanning line and the blood vessel gradient line BL, is within 60 degrees.

[0087] For example, the second vascular wall detection unit 12 may use the vascular running angle BA, Fig.10 The predetermined angle B1 and the angle B2 greater than the angle B1 shown in the figure, when the relationship BA < 60 is satisfied, the Doppler deflection angle is set to 0 degrees, when the relationship 60 ≤ BA < 60 + B1 is satisfied, the Doppler deflection angle is set to the angle B1, and when the relationship 60 + B1 ≤ BA is satisfied, the Doppler deflection angle is set to the angle B2. Here, for example, the angle B1 can be preset to 15 degrees, and the angle B2 can be preset to 30 degrees.

[0088] like Fig.12 As shown, the gate setting unit 14 sets the Doppler gate DG having a center position and a size determined based on the coordinates of the blood vessel anterior wall W1 and the blood vessel posterior wall W2 detected by the second blood vessel wall detection unit 12, within the blood vessel region BR on the B-mode image UB. At this time, the gate setting unit 14 may set the midpoint C between the positions of two points X3 and X4 detected by the second blood vessel wall detection unit 12 as the position of the blood vessel anterior wall W1 and the blood vessel posterior wall W2 as the center position of the Doppler gate DG, and set the Doppler gate DG on a virtual straight line JL that passes through the midpoint C and is inclined with respect to the depth direction D1 by a set Doppler deflection angle.

[0089] The straight line JL corresponds to the scanning line. Furthermore, the gate setting unit 14 may set a length calculated by multiplying the second blood vessel diameter DS calculated by the second blood vessel wall detection unit 12 by a predetermined value as the gate width LG of the Doppler gate DG. Here, the predetermined value multiplied by the second blood vessel diameter DS is a number greater than 0 and less than 1.00, such as 0.75, and is determined by, for example, an input operation of a user via the input device 18.

[0090] And, if Fig.12 As shown, the gate setting unit 14 displays the set Doppler gate DG on the display device 9 by superimposing it on the B-mode image UB.

[0091] The Doppler processing unit 7 acquires the Doppler data in the Doppler gate DG set by the gate setting unit 14 in the blood vessel region BR, and generates a Doppler waveform image based on the acquired Doppler data. Fig.13 As shown, the Doppler processing unit 7 has a structure in which a quadrature detection unit 29, a high-pass filter 30, a fast Fourier transform unit 31 and a Doppler waveform image generating unit 32 are connected in series in sequence, and a data memory 33 is connected to the output end of the quadrature detection unit 29.

[0092] The quadrature detection unit 29 performs quadrature detection on the reception data generated by the reception circuit 4 by mixing a carrier signal of a reference frequency with the reception data, and converts the received data into complex data.

[0093] The high-pass filter 30 functions as a so-called wall filter, and removes frequency components derived from the motion of the in vivo tissue of the subject from the complex data generated by the orthogonal detection unit 29 .

[0094] The fast Fourier transform unit 31 performs Fourier transform on complex data of a plurality of sample points to perform frequency analysis and obtain the blood flow velocity, thereby generating a spectrum signal.

[0095] The Doppler waveform image generating unit 32 generates a Doppler waveform image signal by arranging the spectrum signal generated by the fast Fourier transform unit 31 on the time axis and expressing the magnitude of each frequency component by brightness. Hereinafter, the Doppler waveform image signal generated by the Doppler waveform image generating unit 32 is simply referred to as a Doppler waveform image.

[0096] Furthermore, the data memory 33 stores the complex data converted from the received data by the quadrature detection unit 29 .

[0097] The blood flow velocity calculation unit 15 calculates the blood flow velocity by a so-called pulse Doppler method based on the Doppler data acquired by the Doppler processing unit 7. Alternatively, the blood flow velocity calculation unit 15 may calculate an average blood flow velocity for each cardiac cycle.

[0098] The blood flow measurement unit 16 calculates the cross-sectional area of ​​the blood vessel B based on the second blood vessel diameter DS corresponding to the diameter of the blood vessel B calculated by the second blood vessel diameter calculation unit 13, assuming that the blood vessel has a circular cross-section. Furthermore, the blood flow measurement unit 16 measures the blood flow rate representing the volume of blood flowing through the blood vessel B per unit time based on the calculated cross-sectional area of ​​the blood vessel B and the blood flow velocity calculated by the blood flow velocity calculation unit 15.

[0099] The device control unit 17 controls each unit of the ultrasonic diagnostic apparatus 1 based on a program stored in advance in the storage unit 19 or the like and an input operation performed by a user via the input device 18 .

[0100] The display control unit 8 performs predetermined processing on the B-mode image UB generated by the B-mode processing unit 6 and the Doppler waveform image generated by the Doppler processing unit 7 under the control of the device control unit 17 , and displays the B-mode image UB and the Doppler waveform image on the display device 9 .

[0101] The display device 9 displays the B-mode image UB, the Doppler waveform image, etc. under the control of the display control unit 8 , and includes, for example, a display device such as an LCD (Liquid Crystal Display) or an organic EL display (Organic Electroluminescence Display).

[0102] The input device 18 is used by the user to perform input operations, and may be configured to include a keyboard, a mouse, a trackball, a touch pad, a touch panel, and the like.

[0103] The storage unit 19 stores the action program of the ultrasonic diagnostic device 1, etc., and can use a flash memory, HDD (Hard Disk Drive), SSD (Solid State Drive), FD (Flexible Disk), MO optical disc (Magneto-Optical disc), MT (Magnetic Tape), RAM (Random Access Memory), CD (Compact Disc), DVD (Digital Versatile Disc), SD card (Secure Digital card), USB memory (Universal Serial Bus memory) and other recording media or servers, etc.

[0104] The processor 22 including the B-mode processing unit 6, the Doppler processing unit 7, the display control unit 8, the first vascular wall detection unit 10, the first vascular diameter calculation unit 11, the second vascular wall detection unit 12, the second vascular diameter calculation unit 13, the gate setting unit 14, the blood flow velocity calculation unit 15, the blood flow measurement unit 16, and the device control unit 17 is composed of a CPU (Central Processing Unit) and a control program for causing the CPU to perform various processes, but may be composed of an FPGA (Field Programmable Gate Array), a DSP (Digital Signal Processor), an ASIC (Application Specific Integrated Circuit), a GPU (Graphics Processing Unit), or other ICs (Integrated Circuits), or may be composed of a combination of these.

[0105] Furthermore, part or all of the B-mode processing unit 6, the Doppler processing unit 7, the display control unit 8, the first vascular wall detection unit 10, the first vascular diameter calculation unit 11, the second vascular wall detection unit 12, the second vascular diameter calculation unit 13, the gate setting unit 14, the blood flow velocity calculation unit 15, the blood flow measurement unit 16, and the device control unit 17 of the processor 22 may be integrated into one CPU or the like.

[0106] Below, use Fig.14 The flowchart shown will explain in detail the operation of the ultrasonic diagnostic apparatus 1 in the first embodiment.

[0107] First, in step S1, in order for the user to capture a short-axis image of the blood vessel B of the subject, a B-mode image UB is generated in a state where the ultrasonic probe 21 is in contact with the body surface of the subject, and the generated B-mode image UB is displayed on the display device 9. When the B-mode image UB is generated, ultrasonic beams are transmitted from the plurality of transducers of the transducer array 2 according to the drive signal from the transmission circuit 3, and the receiving signals are output from each transducer that receives the ultrasonic echo from the subject to the receiving circuit 4, amplified by the amplifier 23 and AD-converted by the AD converter 24, and then phased and added by the beamformer 25, thereby generating received data. The received data is subjected to envelope detection processing by the signal processor 26 in the B-mode processor 6 to become a B-mode image signal, and is output to the display controller 8 via the DSC 27 and the image processor 28, so that the B-mode image UB is displayed on the display device 9 under the control of the display controller 8.

[0108] In step S2, the first vascular wall detection unit 10 sets a search region R1 in the B-mode image UB generated in step S1, and determines whether there is a short-axis image of the blood vessel B in the set search region R1. Figure 4 As shown, the first blood vessel wall detection unit 10 detects the brightness of the image on the search line SL1 while scanning the virtual search line SL1 extending along the depth direction D1 in the search area R1 along the lateral direction D2, so as to generate a Figure 5 Brightness distribution shown.

[0109] The first vascular wall detection unit 10 calculates the difference L1 between the two depths J1 and the depth J2 at which the brightness value in the generated brightness distribution becomes the maximum value greater than the constant brightness threshold value K1 while scanning the search line SL1 along the lateral direction D2. For example, when the value of the difference L1 calculated while scanning the search line SL1 from one end to the other end in the lateral direction D2 of the search area R1 changes so as to have the maximum value, the first vascular wall detection unit 10 determines that the short-axis image of the blood vessel B exists in the search area R1. On the other hand, when the value of the difference L1 does not change so as to have the maximum value but is almost constant, the first vascular wall detection unit 10 determines that the short-axis image of the blood vessel B does not exist in the search area R1.

[0110] If it is determined in step S2 that there is no short-axis image of the blood vessel B in the search region R1 , the process returns to step S1 , and the user adjusts the position and orientation of the ultrasonic probe 21 while generating a B-mode image UB.

[0111] In step S2, when it is determined that the short-axis image of the blood vessel B exists in the search region R1, the first blood vessel wall detection unit 10 detects the loci of the points X1 and X2 corresponding to the depths J1 and J2 at which the brightness value in the brightness distribution becomes maximum as the blood vessel wall. The first blood vessel wall detection unit 10 also sends information on the positions of the points X1M and X2M corresponding to the depths J1M and J2M at which the difference L1 calculated while scanning the search line SL1 along the horizontal direction D2 becomes the maximum value L1M to the first blood vessel diameter calculation unit 11.

[0112] In step S3, the first blood vessel diameter calculation unit 11 calculates the first blood vessel diameter DF corresponding to the diameter of the blood vessel B by measuring the distance between the points X1M and X2M on the blood vessel wall corresponding to the depths J1M and J2M at which the difference L1 becomes maximum detected in step S2. Figure 4 As shown, the first blood vessel diameter calculation unit 11 displays the calculated first blood vessel diameter DF on the display device 9 .

[0113] In the next step S4 , in order to capture a long-axis image of the blood vessel B, the user changes the orientation of the ultrasonic probe 21 to generate a B-mode image UB.

[0114] In step S5, the second vascular wall detection unit 12 determines whether or not there is a long-axis image of the blood vessel B in the B-mode image UB generated in step S4. Figure 6 As shown, the second vascular wall detection unit 12 sets a search area R2 on the B-mode image UB, and detects the brightness on the search line SL2 while scanning a virtual search line SL2 extending along the detection depth direction D1 along the horizontal direction D2 in the set search area R2. Figure 7 Brightness distribution shown.

[0115] The second blood vessel wall detection unit 12 calculates the difference L2 between the two depths J3 and J4 at which the brightness value in the brightness distribution generated while scanning the search line SL2 along the horizontal direction D2 becomes the maximum value greater than the constant brightness threshold value K2, and when the calculated difference L2 has a value that is almost constant, it is determined that the long-axis image of the blood vessel B exists in the search area R2 of the B-mode image UB, and when the difference L2 does not have a value that is almost constant, it is determined that the long-axis image of the blood vessel B does not exist in the search area R2.

[0116] If it is determined in step S5 that the long-axis image of the blood vessel B does not exist in the B-mode image UB, the process returns to step S4 , and the user adjusts the position and orientation of the ultrasonic probe 21 to generate a new B-mode image UB.

[0117] In step S5, when it is determined that the long-axis image of the blood vessel B exists in the B-mode image UB, the second blood vessel wall detection unit 12 detects the positions of depths J3 and J4 where the brightness value reaches a maximum value in the long-axis image of the identified blood vessel B as the positions of the blood vessel anterior wall W1 and the blood vessel posterior wall W2, respectively.

[0118] In step S6, the second blood vessel diameter calculation unit 13 calculates the second blood vessel diameter DS corresponding to the diameter of the blood vessel B based on the long-axis image of the blood vessel B detected in step S5. For example, the second blood vessel diameter calculation unit 13 calculates the maximum distance in the depth direction D1 between the blood vessel anterior wall W1 and the blood vessel posterior wall W2 as the second blood vessel diameter DS. Figure 6 As shown, the second blood vessel diameter calculation unit 13 displays the calculated second blood vessel diameter DS on the display device 9 .

[0119] In step S7, the second blood vessel diameter calculation unit 13 compares the calculated second blood vessel diameter DS with the first blood vessel diameter DF calculated in step S3 to determine whether the second blood vessel diameter DS has a value within a predetermined range including the first blood vessel diameter DF. The predetermined range is set to, for example, a range having a lower limit value lower than the first blood vessel diameter DF by a predetermined value and an upper limit value higher than the first blood vessel diameter DF by a predetermined value.

[0120] In step S7, if it is determined that the second blood vessel diameter DS is outside the predetermined range, the process returns to step S4 and the process of steps S4 to S7 is repeated. At this time, the user adjusts the position of the ultrasonic probe 21 so that the value of the second blood vessel diameter DS approaches the value of the first blood vessel diameter DF while checking the value of the second blood vessel diameter DS displayed on the display device 9.

[0121] In step S7, when it is determined that the second blood vessel diameter DS is within the predetermined range, it is determined that a B-mode image UB including a long-axis image of the blood vessel B having the first blood vessel diameter DF, i.e., a long-axis image of the blood vessel B representing a longitudinal section passing through the center of the blood vessel B, has been obtained, and the process proceeds to step S8.

[0122] In step S8, the second vascular wall detection unit 12 estimates the gradient of the blood vessel B using the B-mode image UB including the long-axis image of the blood vessel B having the second blood vessel diameter DS within the predetermined range obtained in step S7, and estimates the blood vessel running angle BA based on the estimated gradient of the blood vessel B. The second vascular wall detection unit 12 can estimate the gradient of the blood vessel B by, for example, estimating a straight line passing through a plurality of positions on the blood vessel anterior wall W1 and a straight line passing through a plurality of positions on the blood vessel posterior wall W2 detected in step S5 and averaging the inclinations of the estimated two straight lines, thereby estimating the gradient of the blood vessel B. Figure 8As shown, a virtual blood vessel gradient line BL is obtained indicating the gradient of the blood vessel B. The second blood vessel wall detection unit 12 can estimate the angle between the obtained blood vessel gradient line BL and a virtual straight line AL along the depth direction D1 of the B-mode image UB as a blood vessel running angle BA.

[0123] In the next step S9, the second vascular wall detection unit 12 uses the vascular advancement angle BA estimated in step S8 to set a B-mode deflection angle indicating the inclination of the scanning line when the B-mode processing unit 6 generates the B-mode image UB. At this time, for example, the second vascular wall detection unit 12 can use the vascular advancement angle BA, Fig. 9 The predetermined angle A1 and the predetermined angle A2 greater than the angle A1 are shown. When the relationship 90-BA<A1 / 2 is satisfied, the B-mode deflection angle is set to 0 degrees. When the relationship A1 / 2≤90-BA<A2 / 2 is satisfied, the B-mode deflection angle is set to the angle A1. When the relationship A2 / 2≤90-BA is satisfied, the B-mode deflection angle is set to the angle A2. Here, for example, the angle A1 can be preset to 7.5 degrees, and the angle A2 can be preset to 15 degrees.

[0124] In step S10, the second vascular wall detection unit 12 uses the vascular advancement angle BA estimated in step S8 to set a Doppler deflection angle indicating the inclination of the scanning line when the Doppler processing unit 7 acquires Doppler data. At this time, for example, the second vascular wall detection unit 12 may use the vascular advancement angle BA, such as Fig.10 The predetermined angle B1 and the angle B2 greater than the angle B1 shown in the figure, when the relationship BA < 60 is satisfied, the Doppler deflection angle is set to 0 degrees, when the relationship 60 ≤ BA < 60 + B1 is satisfied, the Doppler deflection angle is set to the angle B1, and when the relationship 60 + B1 ≤ BA is satisfied, the Doppler deflection angle is set to the angle B2. Here, for example, the angle B1 can be preset to 15 degrees, and the angle B2 can be preset to 30 degrees.

[0125] In step S11, Fig.12As shown, the gate setting unit 14 sets a Doppler gate DG having a center position and a size determined based on the coordinates of the blood vessel front wall W1 and the blood vessel back wall W2 detected in step S5, in the blood vessel region BR on the B-mode image UB used when estimating the blood vessel advancing angle BA in step S8. At this time, the gate setting unit 14 may set, for example, the midpoint C of the positions of the two points X3 and X4 detected as the positions of the blood vessel front wall W1 and the blood vessel back wall W2 in step S5 as the center position of the Doppler gate DG, and may set the length calculated by multiplying the second blood vessel diameter DS measured in step S6 by a predetermined value as the gate width LG of the Doppler gate DG. Here, the predetermined value to be multiplied by the second blood vessel diameter DS is a number greater than 0 and less than 1.00, such as 0.75, and may be determined, for example, by an input operation of the user via the input device 18.

[0126] And, if Fig.12 As shown, the gate setting unit 14 displays the set Doppler gate DG on the display device 9 by superimposing it on the B-mode image UB.

[0127] In step S12, the Doppler processing unit 7 starts to continuously generate the Doppler waveform image, and displays the generated Doppler waveform image on the display device 9. Fig.12 As shown in FIG. 1 , the Doppler processing unit 7 acquires the Doppler data within the Doppler gate DG set in step S10, continuously generates Doppler waveform images based on the acquired Doppler data, and displays the generated Doppler waveform images on the display device 9. In addition, the B-mode processing unit 6 also starts to continuously generate the B-mode image UB, and displays the generated B-mode image UB on the display device 9. Thus, the two images of the B-mode image UB and the Doppler waveform image are continuously generated, and as shown in FIG. Fig.17 As shown, the B-mode image UB and the Doppler waveform image UD are displayed on the display device 9 .

[0128] In step S13, the Doppler waveform WD in the Doppler waveform image UD generated in step S11 is adjusted so that the Doppler processing unit 7 can accurately obtain Doppler data. Fig.15As shown in FIG. 1 , the Doppler waveform WD changes periodically with the heartbeat, so the Doppler waveform WD is adjusted, for example, from the time point when the start position and the end position of the heartbeat cycle are detected. Furthermore, the adjustment of the Doppler waveform WD includes the adjustment of the position of the horizontal axis of the graph of the Doppler waveform WD, that is, the baseline, and the adjustment of the scale of the vertical axis of the Doppler waveform WD. When adjusting the Doppler waveform WD, not only the display of the Doppler waveform WD in the display device 9 is adjusted, but also the repetition frequency of the ultrasonic pulses emitted from the transducer array 2 of the ultrasonic probe 21 into the subject by controlling the transmitting circuit 3 by the device control unit 17 is adjusted. In this way, for example, the Doppler waveform WD is adjusted so that the maximum value and the minimum value of the Doppler waveform WD fall within 70% of the scale of the vertical axis.

[0129] Normally, blood flow velocity in blood vessels increases during the systole of the heart and decreases during the diastole of the heart. Fig.15 As shown, the change amount of the Doppler waveform WD is large in the systolic period P1, and the change amount of the Doppler waveform WD is small in the diastolic period P2. Here, in step S14, the period information of the Doppler waveform WD is acquired, and it is determined whether the current time point is the diastolic period P2 of the heart of the subject based on the acquired period information. If it is determined that the current time point is not the diastolic period P2 of the heart of the subject, the processing of step S14 is re-implemented. If it is determined that the current time point is the diastolic period P2 of the heart of the subject, the process proceeds to step S15.

[0130] In step S15, the two images of the B-mode image UB and the Doppler waveform image UD displayed on the display device 9 are frozen and displayed. Here, freezing and displaying the B-mode image UB and the Doppler waveform image UD means that, in a state where the B-mode image UB continuously generated by the B-mode processing unit 6 and the Doppler waveform image UD continuously generated by the Doppler processing unit 7 are displayed on the display device 9, the display of the B-mode image UB and the Doppler waveform image UD is temporarily stopped, and a single still B-mode image UB and a single still Doppler waveform image UD are displayed on the display device 9.

[0131] In this way, the Doppler data in the diastolic period P2 in which the amount of change in the Doppler waveform WD is small can be used for the measurement of the blood flow rate.

[0132] In the next step S16, the blood flow in the blood vessel region BR is automatically measured. Fig.16 The flowchart shown in FIG. 1 illustrates step S16. Step S16 is composed of steps S18 to S20.

[0133] First, in step S18 , the blood flow measurement unit 16 calculates the cross-sectional area of ​​the blood vessel B based on the second blood vessel diameter DS determined to be within a predetermined range in step S7 , assuming that the blood vessel B has a circular cross section.

[0134] Next, in step S19, the blood velocity calculator 15 calculates the blood velocity based on the Doppler data acquired by the Doppler processor 7 when the B-mode image UB and the Doppler waveform image UD are freeze displayed in step S15. At this time, the blood velocity calculator 15 may calculate the average blood velocity within the cardiac cycle.

[0135] In the next step S20 , the blood flow measurement unit 16 calculates the blood flow rate indicating the volume of blood flowing in the blood vessel B per unit time based on the cross-sectional area of ​​the blood vessel B calculated in step S18 and the blood flow velocity calculated in step S19 .

[0136] In this way, the automatic measurement of blood flow in step S16 is completed.

[0137] In step S17, the blood flow measurement result obtained in step S16 is displayed on the display device 9. For example, Fig.17 As shown, the blood flow measurement value MV is displayed on the display device 9 together with the B-mode image UB and the Doppler waveform image UD.

[0138] In this way, when the measured value MV of the blood flow rate is displayed on the display device 9, the operation of the ultrasonic diagnostic apparatus 1 is terminated.

[0139] In summary, according to the ultrasonic diagnostic device 1 involved in the first embodiment of the present invention, the first blood vessel diameter DF is calculated based on the B-mode image UB representing the short-axis image of the blood vessel B, the B-mode image UB representing the long-axis image passing through the center of the blood vessel B is accurately acquired based on the first blood vessel diameter DF, and the blood flow is measured using the B-mode image UB representing the acquired long-axis image of the blood vessel B. Therefore, the fluctuation of the blood flow measurement accuracy caused by the user adjusting the position of the ultrasonic probe 21 on the body surface of the subject can be reduced, thereby improving the measurement accuracy.

[0140] Furthermore, the blood flow rate is automatically measured by acquiring a B-mode image UB showing a long-axis image passing through the center of the blood vessel B, and the blood flow rate measurement result is displayed on the display device 9, so that the blood flow rate can be measured easily.

[0141] In particular, although not shown in the figure, even in a situation where the user cannot free both hands, such as when the display device 9 is composed of a small portable display and the user holds the display device 9 in one hand and the ultrasonic probe 21 in the other hand, according to the ultrasonic diagnostic device 1 involved in the first embodiment of the present invention, the user does not need to perform operations via the input device 18, etc., and can therefore easily measure blood flow.

[0142] In step S2, the first vascular wall detection unit 10 sets the search region R1 on the B-mode image UB and searches for the short-axis image of the blood vessel B in the set search region R1. However, the entire B-mode image UB may be searched for the short-axis image of the blood vessel B. However, in order to reduce the amount of calculation required for the search process of the blood vessel B and recognize the short-axis image of the blood vessel B as early as possible, it is preferable to search for the short-axis image of the blood vessel B in the search region R1.

[0143] Similarly, in step S5 , the long-axis image of the blood vessel B may be searched in the entire B-mode image UB. However, from the viewpoint of identifying the long-axis image of the blood vessel B as early as possible, it is preferable to search for the long-axis image of the blood vessel B in the search area R2 .

[0144] Furthermore, when the short-axis image of the blood vessel B is captured, the position of the short-axis image of the blood vessel B in the lateral direction D2 is likely to change on the B-mode images UB of the plurality of frames that are continuously generated due to slight changes in the inclination and position of the ultrasonic probe 21 that is in contact with the body surface of the subject. Therefore, the first blood vessel wall detection unit 10 tracks and identifies the short-axis image of the blood vessel B by, for example, detecting the movement of the short-axis image of the blood vessel B between the B-mode images UB of the consecutive frames. The movement detection of the short-axis image of the blood vessel B can be performed by, for example, scanning the search line SL1 on the entire B-mode image UB and comparing the obtained brightness distribution with the brightness distribution of the short-axis image of the detected blood vessel B. In addition, a common image analysis method such as so-called pattern matching can be used.

[0145] By tracking the short-axis image of the blood vessel B in this manner, even if the short-axis image of the blood vessel B moves between consecutive frames, the first blood vessel diameter DF of the short-axis image of the blood vessel B can be easily calculated.

[0146] And, for example, in step S2, when the short-axis image of the blood vessel B is identified, Fig.18 As shown, the display device 9 may display the measurement point marks M1 and M2 at the positions of the two intersections of the search line SL1 passing through the center of the blood vessel B and the contour line of the blood vessel B (i.e., the positions of the depths J1 and J2 where the difference L1 in the depth direction D1 between the depths J1 and J2 measured in step S2 becomes the maximum). In this way, by displaying the measurement point marks M1 and M2, the user can understand the recognition of the short-axis image of the blood vessel B in step S2 and the measurement position of the blood vessel diameter.

[0147] And similarly, in step S5, when the long-axis image of blood vessel B is identified, Fig.19 As shown, in the display device 9, the measurement point marks M3 and M4 can be displayed at the intersection of the search line SL2 and the blood vessel anterior wall W1 and at the intersection of the search line SL2 and the blood vessel posterior wall W2.

[0148] Furthermore, when the short-axis image of the blood vessel B is identified, the display method such as the color and thickness of the contour line of the identified short-axis image of the blood vessel B may be changed instead of displaying the measurement point marks M1 and M2. Similarly, when the long-axis image of the blood vessel B is identified, the display method such as the color and thickness of the contour line of the identified long-axis image of the blood vessel B may be changed instead of displaying the measurement point marks M3 and M4.

[0149] Furthermore, in step S2 and step S5, the brightness distribution of the image along the search lines SL1 and SL2 is used to identify the short-axis image and the long-axis image of the blood vessel B, but the method for identifying the short-axis image and the long-axis image of the blood vessel B is not limited thereto. For example, a so-called template matching method may be used, in which typical pattern data of the short-axis image and the long-axis image of the blood vessel B are stored in advance as a template, and the similarity with the pattern data is calculated while searching the B-mode image UB with the template, and it is considered that the short-axis image or the long-axis image of the blood vessel B exists at a position where the similarity is greater than a threshold value and is the largest.

[0150] In addition to simple template matching, similarity can also be calculated using, for example, the machine learning method described in Csurka et al.: Visual Categorization with Bags of Keypoints, Proc. of ECCV Workshop on Statistical Learning in Computer Vision, pp. 59-74 (2004) or the general image recognition method using deep learning described in Krizhevsk et al.: ImageNet Classification with Deep Convolutional Neural Networks, Advances in Neural Information Processing Systems 25, pp. 1106-1114 (2012).

[0151] Furthermore, in step S3, the first blood vessel diameter DF is calculated based on the information of the blood vessel wall detected in step S2 for one frame of B-mode image UB, but the first blood vessel diameter DF may be calculated based on the information of the blood vessel wall detected for multiple frames of B-mode image UB. For example, when the value of the first blood vessel diameter DF calculated over a predetermined number of frames such as 5 to 10 frames is less than a predetermined value, the first blood vessel diameter calculation unit 11 may calculate the largest first blood vessel diameter DF among the first blood vessel diameters DF calculated for the predetermined number of B-mode images UB as the final value of the first blood vessel diameter DF. Furthermore, for example, the first blood vessel diameter calculation unit 11 may calculate the average value of the first blood vessel diameters DF calculated for the predetermined number of B-mode images UB as the final value of the first blood vessel diameter DF.

[0152] This can eliminate the case where the calculated first blood vessel diameter DF has an abnormal value such as an extremely large value or an extremely small value relative to the actual diameter of the blood vessel B, and thus the final value of the first blood vessel diameter DF can be accurately calculated.

[0153] Furthermore, the determination in step S7 can be performed based on the second blood vessel diameter DS calculated for the plurality of frames of B-mode images UB. For example, when the second blood vessel diameter DS calculated over a predetermined number of frames such as 5 to 10 frames maintains a predetermined range of 5 to 10 frames including the first blood vessel diameter DF calculated in step S3, the second blood vessel diameter calculation unit 13 can determine that the second blood vessel diameter DS has a value within the predetermined range and proceed to step S8. Thus, the determination accuracy in step S7 can be improved, and a B-mode image UB representing a longitudinal section passing through the center of the blood vessel B can be accurately acquired.

[0154] Furthermore, the second blood vessel diameter calculation unit 13 may calculate the largest second blood vessel diameter DS value among the second blood vessel diameters DS calculated for the B-mode images UB of a predetermined number of frames, which is used when it is determined that the second blood vessel diameter DS has a value within a predetermined range, as the final value of the second blood vessel diameter DS. In this case, the second blood vessel wall detection unit 12 may perform the processing of steps S8 to S11, for example, using the B-mode image UB used when calculating the final second blood vessel diameter DS.

[0155] Furthermore, the second blood vessel diameter calculation unit 13 may average the second blood vessel diameter DS calculated for the B-mode images UB of a predetermined number of frames, which are used when it is determined that the second blood vessel diameter DS has a value within a predetermined range, and calculate the average value as the final value of the second blood vessel diameter DS. In this case, the second blood vessel wall detection unit 12 may perform the processing of steps S8 to S11 using, for example, the last acquired B-mode image UB among the B-mode images UB of a predetermined number of frames.

[0156] Furthermore, in steps S5 to S7, the value of the first blood vessel diameter DF calculated in step S3 may be displayed together with the long-axis image of the blood vessel B and the value of the second blood vessel diameter DS displayed on the display device 9. In this case, the user can adjust the position of the ultrasonic probe 21 so that the second blood vessel diameter DS calculated in step S6 approaches the first blood vessel diameter DF while checking the value of the first blood vessel diameter DF. Therefore, the user can adjust the position of the ultrasonic probe 21 more easily.

[0157] Furthermore, when calculating the first blood vessel diameter DF in step S3, the first blood vessel diameter calculation unit 11 may also calculate the distance between the short-axis image of the blood vessel B and the body surface of the subject as the first blood vessel depth based on the relatively shallower depth J1 among the depths J1 and J2 corresponding to the position of the blood vessel wall detected in step S2, and display the calculated first blood vessel depth on the display device 9.

[0158] Furthermore, when calculating the second blood vessel diameter DS in step S6, the second blood vessel diameter calculation unit 13 can, for example, calculate the distance between the blood vessel front wall W1 and the body surface of the subject as the second blood vessel depth based on the depth J3 corresponding to the position of the blood vessel front wall W1 detected in step S5, and display the calculated second blood vessel depth on the display device 9.

[0159] Here, in steps S4 to S7, both the calculated first blood vessel depth and the second blood vessel depth may be displayed on the display device 9. Thus, the user can compare the first blood vessel depth and the second blood vessel depth to confirm whether the long-axis image of the blood vessel B in the B-mode image UB generated in step S4 corresponds to the short-axis image of the blood vessel B in the B-mode image UB generated in step S1, and adjust the position of the ultrasonic probe 21. Thus, it is possible to prevent the long-axis image of the blood vessel B that does not correspond to the short-axis image of the blood vessel B in the B-mode image UB generated in step S1 from being captured in step S4, thereby capturing an appropriate long-axis image of the blood vessel B, and thus improving the measurement accuracy of the blood flow.

[0160] Furthermore, for example, when the long-axis image of the blood vessel B is recognized in step S5, the first blood vessel depth may be added. For example, when the variation range of the difference L2 between the depths J3 and J4 calculated by the second blood vessel wall detection unit 12 while scanning the search line SL2 along the transverse direction D2 is less than the variation range threshold and the second blood vessel depth has a value within the depth range including the first blood vessel depth, it is determined that the long-axis image of the blood vessel B exists in the search region R2. Furthermore, when the variation range of the difference L2 calculated while scanning the search line SL2 along the transverse direction D2 is greater than the variation range threshold or the second blood vessel depth has a value outside the depth range, it is determined that the long-axis image of the blood vessel B does not exist in the search region R2.

[0161] This can also prevent the long-axis image of the blood vessel B that does not correspond to the short-axis image of the blood vessel B in the B-mode image UB generated in step S1 from being captured in step S4 .

[0162] Furthermore, a step of continuously generating a B-mode image UB including the long-axis image of the blood vessel B and determining that the position of the long-axis image of the blood vessel B has stabilized may be set between step S11 and step S12, so that the process proceeds to step S11 with the stabilization of the position of the long-axis image of the blood vessel B as a trigger. For example, when the position of the long-axis image of the blood vessel B in the multiple frames of B-mode images UB generated within a predetermined time such as 1 second changes by less than a predetermined value such as 0.2 mm, the position of the long-axis image of the blood vessel B is determined to be stable. Furthermore, when the position of the long-axis image of the blood vessel B in the multiple frames of B-mode images UB generated within a predetermined time such as 1 second changes by more than a predetermined value such as 0.2 mm, the position of the long-axis image of the blood vessel B is determined to be unstable.

[0163] In this way, step S11 and subsequent processing are performed with the position of the long-axis image of the blood vessel B in the B-mode image UB being stable (i.e., the position of the ultrasonic probe 21 arranged on the body surface of the subject being stable), so that the blood flow can be measured using a stable image, thereby improving the measurement accuracy of the blood flow.

[0164] Furthermore, although the processing of steps S5 to S7 is performed on the B-mode image UB generated in step S4, the processing of steps S5 to S7 may be performed on the B-mode image UB generated in any one of steps S12 to S14. In this case, for example, the calculation of the cross-sectional area of ​​the blood vessel B in step S18 may be performed using the second blood vessel diameter DS calculated for the B-mode image UB generated in any one of steps S12 to S14 and determined to be within the predetermined range including the first blood vessel diameter DF calculated in step S3, instead of the second blood vessel diameter DS determined to be within the predetermined range in step S7.

[0165] Furthermore, in step S18, instead of calculating the cross-sectional area of ​​the blood vessel B based on the second blood vessel diameter DS determined to be within the predetermined range by the blood flow measurement unit 16, the cross-sectional area of ​​the blood vessel B may be calculated based on the first blood vessel diameter DF calculated in step S3. For example, when the first blood vessel diameter DF is larger than the second blood vessel diameter DS determined to be within the predetermined range, the cross-sectional area of ​​the blood vessel B is calculated based on the first blood vessel diameter DF.

[0166] Furthermore, in step S12, the Doppler waveform image UD is generated and displayed on the display device 9. However, as long as the data of the Doppler waveform WD can be acquired, the Doppler waveform image UD does not necessarily need to be displayed on the display device 9. Thus, even when the Doppler waveform image UD is not displayed on the display device 9, the blood flow rate is measured in step S16 based on the data of the Doppler waveform WD acquired in step S13 and the value of the second blood vessel diameter DS determined to be within the predetermined range in step S7, as in the case where the Doppler waveform image UD is displayed on the display device 9. Furthermore, when the Doppler waveform image UD is not displayed on the display device 9, instead of freezing the display of the Doppler waveform image UD on the display device 9 in step S15, only the acquisition of the data of the Doppler waveform WD may be stopped.

[0167] Furthermore, an example is shown in which the adjustment of the Doppler waveform WD is performed from the time when the start position and the end position of the cardiac cycle in the Doppler waveform WD are detected in step S13, but the adjustment of the Doppler waveform WD in step S13 may be automatically performed, for example, when a predetermined time such as 2 seconds has passed since the generation of the Doppler waveform image UD in step S12 is started.

[0168] Furthermore, when adjusting the Doppler waveform WD, in addition to adjusting the position of the baseline and the scale of the vertical axis of the Doppler waveform WD, the position of the Doppler gate DG may be readjusted so that the maximum and minimum values ​​of the Doppler waveform WD fall within 70% of the scale of the vertical axis.

[0169] However, since the accuracy of the blood velocity calculated by the blood velocity calculation unit 15 and the accuracy of the blood flow measured by the blood flow measurement unit 16 can be improved by adjusting the Doppler waveform WD, it is preferable to implement step S12.

[0170] Then, in step S14, the current time point is the diastolic period P2 of the heart of the subject, which is used as a trigger to proceed to the next step S15. However, the trigger for proceeding from step S14 to step S15 is not limited to this.

[0171] For example, it is also possible to determine whether the current time point is the systolic period P1 instead of determining whether the current time point is the diastolic period P2. In this case, if it is determined that the current time point is not the systolic period P1, the determination of whether the current time point is the systolic period P1 is repeated, and if it is determined that the current time point is the systolic period P1, the next step S15 is entered. However, regarding the change amount of the Doppler waveform WD, the diastolic period P2 is smaller than the systolic period P1, so it is more preferable to use the current time point as the diastolic period P2 as a trigger to enter step S15 than to use the current time point as the systolic period P1 as a trigger to enter step S15.

[0172] Furthermore, for example, instead of executing step S14 , the process may proceed to step S15 when a predetermined time such as two seconds has passed since the completion of the operation of adjusting the Doppler waveform WD in step S13 is used as a trigger.

[0173] Furthermore, for example, instead of executing step S14, the process may proceed to step S15 using the timing when the start position and the end position of a plurality of cardiac cycles such as two or three cycles are detected in the Doppler waveform WD as a trigger.

[0174] Furthermore, when the B-mode image UB and the Doppler waveform image UD are frozen and displayed on the display device 9 in step S15, the Doppler waveform image UD may be scrolled back so that the end position of the diastolic period P2 or the end position of the systolic period P1 in the Doppler waveform WD is aligned with, for example, the right end of the Doppler waveform image UD. In this way, by changing the position of the Doppler waveform WD displayed on the display device 9 after the B-mode image UB and the Doppler waveform image UD are frozen and displayed, the time phase of the B-mode image UB displayed on the display device 9 can be aligned with the diastolic period P2 or the systolic period P1.

[0175] Furthermore, after determining that the second blood vessel diameter DS has a value within the predetermined range in step S7, the estimation of the blood vessel running angle BA in step S8 is performed, but the processing of step S8 may be performed between steps S5 to S7. Thus, the estimation of the blood vessel running angle BA is not particularly limited as long as it is performed before the processing of steps S9 to S11.

[0176] Furthermore, in step S6, the second blood vessel diameter calculation unit 13 calculates the distance in the depth direction D1 between the blood vessel front wall W1 and the blood vessel rear wall W2 detected in step S5 as the second blood vessel diameter DS. However, for example, the second blood vessel diameter DS may be calculated by performing the process of estimating the blood vessel running angle BA in step S8 before performing the process of calculating the second blood vessel diameter DS in step S6. Figure 6 A search line SL2 is set in a direction perpendicular to the blood vessel gradient line BL to calculate the blood vessel diameter in a direction perpendicular to the traveling direction of the blood vessel B as the second blood vessel diameter DS. This allows the second blood vessel diameter DS to be calculated more accurately, thereby improving the measurement accuracy of the blood flow rate.

[0177] Furthermore, in step S8 , the second vascular wall detection unit 12 estimates the gradient of the blood vessel based on both the anterior vascular wall W1 and the posterior vascular wall W2 . However, a virtual blood vessel gradient line BL indicating the gradient of the blood vessel may be estimated based on either the anterior vascular wall W1 or the posterior vascular wall W2 .

[0178] Furthermore, after the B-mode deflection angle is set in step S9, the Doppler deflection angle is set in step S10, and after the Doppler deflection angle is set, the Doppler gate DG is set in step S11, but the order of performing steps S9 to S11 is not particularly limited and can be interchanged. For example, after the B-mode deflection angle is set in step S9, the setting of the Doppler deflection angle in step S10 and the setting of the Doppler gate DG in step S11 can be performed simultaneously. Furthermore, for example, the processing of steps S9 to S11 can be performed in the order of setting the Doppler deflection angle in step S10, setting the Doppler gate DG in step S11, and setting the B-mode deflection angle in step S9.

[0179] Furthermore, in step S10, the second vascular wall detection unit 12 sets the Doppler deflection angle so that the angle correction value relative to the blood vessel advancing angle BA is within 60 degrees, but the blood vessel advancing angle BA may be set to the angle correction value of the Doppler deflection angle. In this case, the angle correction value of the Doppler deflection angle may exceed 60 degrees, but when the angle correction value of the Doppler deflection angle exceeds 60 degrees, information indicating that the angle correction value exceeds 60 degrees may be displayed on the display device 9. For example, the user can re-perform the automatic measurement of the blood flow velocity by the ultrasonic diagnostic apparatus 1 by confirming the information indicating that the angle correction value exceeds 60 degrees and adjusting the inclination of the ultrasonic probe 21 in contact with the subject.

[0180] Furthermore, after setting the Doppler gate DG in step S11, the blood vessel region BR including the Doppler gate DG in the B-mode image UB may be enlarged and displayed on the display device 9. Therefore, the blood vessel region BR on the enlarged B-mode image UB can be clearly confirmed. In this case, the blood vessel diameter is measured based on the enlarged B-mode image UB. For example, due to the resolution of the B-mode image UB, the position of the blood vessel wall can be detected more accurately by detecting the blood vessel wall based on the enlarged B-mode image UB than by detecting the blood vessel wall based on the B-mode image UB before enlargement. Therefore, by measuring the blood vessel diameter based on the enlarged B-mode image UB, the measurement accuracy of the blood flow rate can be improved.

[0181] Furthermore, although not shown in the figure, a guide unit for guiding the user may be set in the ultrasonic diagnostic apparatus 1, and in step S1, a message to align the short-axis image of the blood vessel B within the search area R1 may be displayed on the display device 9 by the guide unit. This can improve the accuracy of the first blood vessel wall detection unit 10 in recognizing the short-axis image of the blood vessel B, thereby setting the search line SL at a more appropriate position. Therefore, the blood vessel diameter and the cross-sectional area of ​​the blood vessel can be accurately obtained, thereby improving the measurement accuracy of the blood flow rate.

[0182] In this case, a message to the effect that the long-axis image of the blood vessel B is aligned within the search region R2 may be displayed on the display device 9 in step S4. This can improve the accuracy of the second vascular wall detection unit 12 in recognizing the long-axis image of the blood vessel B.

[0183] In addition, it is generally known that the blood vessel diameter changes periodically between the minimum diameter and the maximum diameter with the heartbeat. Therefore, although not shown in the figure, the second blood vessel diameter calculation unit 13 may, for example, superimpose a graph showing the time change of the second blood vessel diameter DS corresponding to the diameter of the blood vessel B (i.e., the second blood vessel diameter DS calculated for the B-mode image UB including the long-axis image of the longitudinal section corresponding to the center of the blood vessel B) on the B-mode image UB and display it on the display device 9. Thus, the user can easily grasp the time change of the second blood vessel diameter DS corresponding to the diameter of the blood vessel B.

[0184] Furthermore, by obtaining information on the time variation of the second blood vessel diameter DS corresponding to the diameter of the blood vessel B, the minimum diameter and maximum diameter of the blood vessel B in the long-axis image can be easily measured. Here, for example, an elasticity index calculation unit (not shown) can be set in the ultrasonic diagnostic apparatus 1, and the elasticity index calculation unit measures the minimum diameter and maximum diameter of the blood vessel B based on the information on the time variation of the second blood vessel diameter DS corresponding to the diameter of the blood vessel B, and calculates an elasticity index representing the elasticity of the blood vessel based on the measured minimum diameter and maximum diameter. The elasticity index calculation unit can, for example, calculate the difference between the maximum diameter and the minimum diameter of the blood vessel as the elasticity index. Furthermore, the elasticity index calculation unit can calculate a value standardized by dividing the difference between the maximum diameter and the minimum diameter of the blood vessel by the minimum diameter of the blood vessel as the elasticity index.

[0185] Furthermore, by using a sphygmomanometer (not shown) to measure the subject's blood pressure Q1 at the time when the diameter of the blood vessel becomes minimum and the subject's blood pressure Q2 at the time when the diameter of the blood vessel becomes maximum, the elasticity index calculation unit can also use the blood pressures Q1, Q2, the minimum diameter DA of the blood vessel, and the maximum diameter DB of the blood vessel to calculate the stiffness parameter X = {Log (Q2 / Q1)} / {(DB / DA)-1} recorded in Japanese Patent Gazette No. 5384919 as an elasticity index.

[0186] Second Embodiment

[0187] In step S12 of the operation of the ultrasonic diagnostic apparatus 1 according to the first embodiment, the B-mode image UB and the Doppler waveform image UD are simultaneously generated. However, the generation of the B-mode image UB may be temporarily stopped to generate only the Doppler waveform image UD.

[0188] Below, use Fig. 20 The operation of the ultrasonic diagnostic apparatus 1 according to the second embodiment is described with reference to the flowchart. Fig.14 In the flowchart of the first embodiment shown, steps S21 to S23 are added instead of step S12 , and step S24 is added instead of step S15 .

[0189] Therefore, description of the processing of step S1 to step S11 will be omitted.

[0190] In step S21 following step S11, continuous generation of B-mode images UB is started, and it is determined whether the current time point is the diastolic period P2 of the heart of the subject based on the value of the second blood vessel diameter DS determined to be within the predetermined range in step S7. Fig.21 As shown, usually, the blood vessel diameter changes periodically between the minimum diameter DA and the maximum diameter DB with the heartbeat, and has the maximum diameter DB in the heart's systolic period P1, and has the minimum diameter DA in the heart's diastolic period P2. Therefore, for example, by measuring the minimum diameter DA of the blood vessel, it can be determined that the current time point is the diastolic period P2 of the subject's heart. If it is determined that the current time point is not the diastolic period P2 of the subject's heart, the process of step S21 is re-implemented. If it is determined that the current time point is the diastolic period P2 of the subject's heart, the process proceeds to step S22.

[0191] In step S22 , the B-mode image UB displayed on the display device 9 is freeze-displayed.

[0192] In the next step S23, the Doppler processing unit 7 starts to continuously generate the Doppler waveform image UD and displays the generated Doppler waveform image UD on the display device 9. Thus, the Doppler waveform image UD is displayed on the display device 9 while the B-mode image UB is frozen and displayed.

[0193] When the Doppler waveform image UD is displayed on the display device 9 in this manner, the process proceeds to step S13 , and the Doppler waveform WD in the Doppler waveform image UD generated in step S23 is adjusted.

[0194] Next, in step S14, the period information of the Doppler waveform WD is obtained, and it is determined whether the current time point is the diastolic period P2 of the heart of the subject based on the obtained period information. If it is determined that the current time point is not the diastolic period P2 of the heart of the subject, the processing of step S14 is re-implemented. If it is determined that the current time point is the diastolic period P2 of the heart of the subject, the process proceeds to step S24.

[0195] In step S24, the Doppler waveform image UD displayed on the display device 9 is frozen and displayed. Thus, the B-mode image UB and the Doppler waveform image UD in the diastolic period P2 can be frozen and displayed on the display device 9, and the Doppler data in the diastolic period P2 in which the change amount of the Doppler waveform WD is small can be used for the measurement of blood flow.

[0196] In the next step S16, the blood flow in the blood vessel region BR is automatically measured based on the value of the second blood vessel diameter DS determined to be within the predetermined range in step S7 and the Doppler waveform image UD frozen and displayed in step S24, and in step S17, as shown in FIG. Fig.17 As shown, the blood flow measurement value MV is displayed on the display device 9 together with the B-mode image UB and the Doppler waveform image UD.

[0197] In this way, when the measured value MV of the blood flow rate is displayed on the display device 9, the operation of the ultrasonic diagnostic apparatus 1 is terminated.

[0198] As described above, according to the ultrasonic diagnostic apparatus 1 according to the second embodiment of the present invention, even when the generation of the B-mode image UB is temporarily stopped and only the Doppler waveform image UD is generated, the first blood vessel diameter DF is calculated based on the B-mode image UB representing the short-axis image of the blood vessel B, and the B-mode image UB representing the long-axis image passing through the center of the blood vessel B is accurately acquired based on the first blood vessel diameter DF, and the blood flow is measured using the B-mode image UB representing the acquired long-axis image of the blood vessel B. Therefore, the fluctuation of the measurement accuracy of the blood flow caused by the user adjusting the position of the ultrasonic probe 21 on the body surface of the subject can be reduced, thereby improving the measurement accuracy.

[0199] In step S21, the current time point is the diastolic period P2 of the heart of the subject, which is used as a trigger to proceed to the next step S22. However, the trigger for proceeding from step S21 to step S22 is not limited to this.

[0200] For example, it is also possible to determine whether the current time point is the systolic period P1 instead of determining whether the current time point is the diastolic period P2. In this case, if it is determined that the current time point is not the systolic period P1, the determination of whether the current time point is the systolic period P1 is repeated, and if it is determined that the current time point is the systolic period P1, the next step S22 is entered. However, regarding the change amount of the Doppler waveform WD, the diastolic period P2 is smaller than the systolic period P1, so it is more preferable to use the current time point as the diastolic period P2 as a trigger to enter step S22 than to use the current time point as the systolic period P1 as a trigger to enter step S22.

[0201] Furthermore, for example, step S21 may be omitted. In this case, the setting of the Doppler gate DG on the B-mode image UB in step S11 is used as a trigger, and the B-mode image UB is freeze-displayed on the display device 9 in step S22.

[0202] Furthermore, for example, the elapse of a predetermined time such as 2 seconds from the time when the setting of the Doppler gate DG in step S11 is completed may be used as a trigger for proceeding to step S22 .

[0203] Furthermore, in step S23 , the Doppler waveform image UD is generated and displayed on the display device 9 . However, the Doppler waveform image UD does not necessarily need to be displayed on the display device 9 as long as the data of the Doppler waveform WD can be acquired as in step S12 in the first embodiment.

[0204] Third Embodiment

[0205] The ultrasonic diagnostic apparatus 1 of the first embodiment has a configuration in which the display device 9, the input device 18, and the ultrasonic probe 21 are directly connected to the processor 22. However, the display device 9, the input device 18, the ultrasonic probe 21, and the processor 22 may be indirectly connected via a network, for example.

[0206] like Fig. 22 As shown in FIG. 1 , the display device 9, the input device 18, and the ultrasonic probe 21 of the ultrasonic diagnostic apparatus 1A in the third embodiment are connected to the ultrasonic diagnostic apparatus main body 41 via the network NW. Figure 1 The ultrasonic diagnostic apparatus 1 of the first embodiment shown in the figure is constituted by the transceiver circuit 5 , the storage unit 19 , and the processor 22 , except for the display device 9 , the input device 18 , and the ultrasonic probe 21 .

[0207] Even when the ultrasonic diagnostic apparatus 1A has such a configuration, similarly to the ultrasonic diagnostic apparatus 1 of the first embodiment, the first blood vessel diameter DF is calculated based on the B-mode image UB showing the short-axis image of the blood vessel B, the B-mode image UB showing the long-axis image passing through the center of the blood vessel B is accurately acquired based on the first blood vessel diameter DF, and the blood flow rate is measured using the B-mode image UB showing the acquired long-axis image of the blood vessel B. Therefore, fluctuations in the measurement accuracy of the blood flow rate caused by the user adjusting the position of the ultrasonic probe 21 on the body surface of the subject can be reduced, thereby improving the measurement accuracy.

[0208] Furthermore, since the display device 9, the input device 18, and the ultrasonic probe 21 are connected to the ultrasonic diagnostic apparatus main body 41 via the network NW, the ultrasonic diagnostic apparatus main body 41 can be used as a so-called remote server. Thus, for example, the user can diagnose the subject by preparing the display device 9, the input device 18, and the ultrasonic probe 21 near the user, thereby improving the convenience of performing ultrasonic diagnosis.

[0209] Furthermore, for example, when a portable thin computer called a so-called tablet computer is used as the display device 9 and the input device 18, the user can more easily perform ultrasonic diagnosis of the subject, and the convenience of ultrasonic diagnosis can be further improved.

[0210] In addition, the display device 9, input device 18, and ultrasonic probe 21 are connected to the ultrasonic diagnostic device body 41 via the network NW. In this case, the display device 9, input device 18, and ultrasonic probe 21 can be connected to the network NW by wire or wirelessly.

[0211] Furthermore, the method of the third embodiment has been described as being applicable to the first embodiment, but the method can also be applied to the second embodiment in the same manner.

[0212] Explanation of symbols

[0213] 1. 1A-ultrasonic diagnostic device, 2-transducer array, 3-transmitting circuit, 4-receiving circuit, 5-transmitting and receiving circuit, 6-B mode processing unit, 7-Doppler processing unit, 8-display control unit, 9-display device, 10-first blood vessel wall detection unit, 11-first blood vessel diameter calculation unit, 12-second blood vessel wall detection unit, 13-second blood vessel diameter calculation unit, 14-gate setting unit, 15-blood flow velocity calculation unit, 16-blood flow measurement unit, 17-device Control unit, 18-input device, 19-storage unit, 21-ultrasonic probe, 22-processor, 23-amplifier, 24-AD converter, 25-beam former, 26-signal processor, 27-DSC, 28-image processor, 29-quadrature detector, 30-high-pass filter, 31-fast Fourier transform unit, 32-Doppler waveform image generator, 33-data storage, 41-ultrasonic diagnostic device body, A1, B1, B2 , H-angle, AL, JL-straight line, B-blood vessel, BA-blood vessel advancing angle, BR-blood vessel area, BL-blood vessel gradient line, C-midpoint, E-estimation error, D1-depth direction, D2-lateral direction, DA-minimum diameter, DB-maximum diameter, DF-first blood vessel diameter, DG-Doppler gate, DS-second blood vessel diameter, G1, G2, G3, G4-curve graph, J1, J2, J3, J4-depth, K1, K2-brightness threshold , L1, L2-difference, L1M-maximum value, LG-gate width, M1, M2, M3, M4-measurement point markers, MV-measurement value, NW-network, P1-systole, P2-diastole, R1, R2-search area, SL1, SL2-search line, UB-B mode image, UD-Doppler waveform image, W1-anterior vessel wall, W2-posterior vessel wall, WD-Doppler waveform, X1, X1M, X2, X2M, X3, X4-points.

Claims

1. An ultrasonic diagnostic device comprising: A transducer array, which transmits and receives ultrasonic waves to a subject and obtains a received signal; A B-mode processing unit that generates a B-mode image in which at least a blood vessel is photographed based on the received signal; a display device that displays the B-mode image generated by the B-mode processing unit; a first blood vessel wall detection unit that detects the blood vessel wall in a short-axis direction by analyzing the B-mode image in which the short-axis image of the blood vessel is captured; a first blood vessel diameter calculation unit that calculates a first blood vessel diameter based on the blood vessel wall in the short-axis direction detected by the first blood vessel wall detection unit; a second blood vessel wall detection unit that detects the blood vessel wall in the long-axis direction by analyzing the B-mode image in which the long-axis image of the blood vessel is captured; a second blood vessel diameter calculation unit that calculates a second blood vessel diameter based on the blood vessel wall in the long-axis direction detected by the second blood vessel wall detection unit; a gate setting unit that sets a Doppler gate in the blood vessel on the B-mode image in which the long-axis image is captured; A Doppler processing unit, which obtains Doppler data within the Doppler gate; a blood flow velocity calculation unit, which calculates the blood flow velocity according to the Doppler data; as well as a blood flow measurement unit for measuring the blood flow based on the detected blood vessel wall in the long-axis direction and the detected blood vessel wall in the short-axis direction and the calculated blood flow velocity, The blood flow rate is automatically measured when the second blood vessel diameter calculated by the second blood vessel diameter calculation unit is within a range determined with respect to the first blood vessel diameter calculated by the first blood vessel diameter calculation unit.

2. The ultrasonic diagnostic apparatus according to claim 1, in, The second vascular wall detection unit sets a search line for searching the vascular wall in the long-axis direction on the B-mode image, Based on the brightness distribution of the B-mode image on the set search line, a blood vessel front wall and a blood vessel back wall are detected as blood vessel walls in the long-axis direction.

3. The ultrasonic diagnostic apparatus according to claim 2, in, The second vascular wall detection unit sets detection point marks on the detected anterior vascular wall and posterior vascular wall, respectively, and displays the marks on the display device.

4. The ultrasonic diagnostic apparatus according to claim 2 or 3, in, The gate setting unit sets the Doppler gate having a center position and a size determined based on coordinates of the anterior blood vessel wall and the posterior blood vessel wall detected by the second blood vessel wall detection unit.

5. The ultrasonic diagnostic apparatus according to claim 2 or 3, in, The second vascular wall detection unit estimates a blood vessel running angle based on at least one of the detected anterior blood vessel wall and posterior blood vessel wall, and sets a Doppler deflection angle so that an angle correction value with respect to the blood vessel running angle is within 60 degrees.

6. The ultrasonic diagnostic apparatus according to claim 5, in, The B-mode processing unit generates the B-mode image based on a B-mode deflection angle set based on the blood vessel running angle estimated by the second blood vessel wall detection unit.

7. The ultrasonic diagnostic apparatus according to any one of claims 1 to 3, wherein, the Doppler processing unit generates a Doppler waveform image based on the Doppler data, and the display device displays both the B-mode image generated by the B-mode processing unit and the Doppler waveform image generated by the Doppler processing unit.

8. The ultrasonic diagnostic apparatus according to claim 7, wherein, the Doppler processing unit generates a Doppler waveform image in parallel when the B-mode processing unit generates the B-mode image, and the blood flow rate is measured by the blood flow rate measurement unit after both the B-mode image and the Doppler waveform image are frozen.

9. The ultrasonic diagnostic apparatus according to claim 7, wherein, the Doppler processing unit acquires Doppler data within the Doppler gate after the B-mode image is frozen, generates a Doppler waveform image, and the blood flow rate is measured by the blood flow rate measurement unit after the Doppler waveform image is frozen.

10. The ultrasonic diagnostic apparatus according to any one of claims 1 to 3, wherein, the blood flow rate is automatically measured when the second blood vessel diameter calculated over a predetermined number of frames is maintained within a range determined with respect to the calculated first blood vessel diameter.

11. A control method for an ultrasonic diagnostic apparatus, comprising the following steps: generating at least a B-mode image in which a blood vessel is photographed based on a reception signal obtained by transmitting and receiving ultrasonic waves to a subject; displaying the B-mode image; detecting a blood vessel wall in the short-axis direction by analyzing a short-axis image of the blood vessel photographed in the B-mode image; calculating a first blood vessel diameter based on the detected blood vessel wall in the short-axis direction; detecting a blood vessel wall in the long-axis direction by analyzing the B-mode image in which the long-axis image of the blood vessel is photographed; calculating a second blood vessel diameter based on the detected blood vessel wall in the long-axis direction; setting a Doppler gate within the blood vessel in the B-mode image in which the long-axis image is photographed when the calculated second blood vessel diameter is within a range determined with respect to the calculated first blood vessel diameter; acquiring Doppler data within the Doppler gate; calculating a blood flow velocity based on the Doppler data; and measuring a blood flow rate based on any one of the detected blood vessel wall in the long-axis direction and the detected blood vessel wall in the short-axis direction and the calculated blood flow velocity.

12. A processor for an ultrasonic diagnostic apparatus, which performs the following processing: generating at least a B-mode image in which a blood vessel is photographed based on a reception signal obtained by transmitting and receiving ultrasonic waves to a subject; displaying the B-mode image; detecting a blood vessel wall in the short-axis direction by analyzing a short-axis image of the blood vessel photographed in the B-mode image; calculating a first blood vessel diameter based on the detected blood vessel wall in the short-axis direction; detecting a blood vessel wall in the long-axis direction by analyzing the B-mode image in which the long-axis image of the blood vessel is photographed; calculating a second blood vessel diameter based on the detected blood vessel wall in the long-axis direction; When the calculated second blood vessel diameter is within a range determined with respect to the calculated first blood vessel diameter, setting a Doppler gate within the blood vessel on the B-mode image in which the long-axis image is captured; Acquiring Doppler data within the Doppler gate; calculating blood flow velocity according to the Doppler data; as well as The blood flow rate is measured based on any one of the detected blood vessel wall in the long-axis direction and the detected blood vessel wall in the short-axis direction and the calculated blood flow velocity.

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