Ultrasound diagnostic device and method for controlling the ultrasound diagnostic device

Abstract

To provide an ultrasonic diagnostic apparatus and a control method of the ultrasonic diagnostic apparatus that allow an examiner to easily grasp the depth that an insert reaches when inserting the insert into a blood vessel while taking an ultrasonic image that shows a cross section of a blood vessel of a subject.SOLUTION: An ultrasonic diagnostic apparatus includes: an ultrasonic probe (1); a monitor (23); an image acquisition unit (41) for acquiring ultrasonic images of a plurality of frames capturing a cross section of a blood vessel of a subject continuously while moving the ultrasonic probe (1); an insert detection unit (24) for detecting inserts inserted into a subject from the ultrasonic images of a plurality of frames respectively; and a superimposition display unit (25) for superimposing at least one insert detected from the ultrasonic images of a plurality of frames by the insert detection unit (24) on the ultrasonic image of a newest frame of the ultrasonic images of a plurality of frames, and displaying the superimposition image in the monitor (23).SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an ultrasonic diagnostic apparatus used for observing an object inserted into a blood vessel of a subject, and a method for controlling the ultrasonic diagnostic apparatus. [Background technology]

[0002] A conventional procedure involves inserting an insert such as a puncture needle into a blood vessel of a subject while observing the inside of the subject using a so-called ultrasound diagnostic device. By checking ultrasound images taken by the ultrasound diagnostic device, an examiner can confirm the insert inserted into the subject's blood vessel and advance the insert into the blood vessel. However, a certain level of proficiency in ultrasound examination is often required to accurately determine the position of the insert from the ultrasound images.

[0003] In order to easily grasp the position of an insert, for example, technologies disclosed in Patent Documents 1 and 2 have been developed. Patent Document 1 discloses detecting the tip of the insert based on multiple frames of ultrasound images in which a longitudinal cross section of the insert is captured, and calculating the trajectory of the tip of the insert based on the position of the tip of the insert detected in the multiple frames of ultrasound images. Patent Document 2 discloses calculating the difference between multiple consecutive frames of ultrasound images in which a longitudinal cross section of the insert is captured, and displaying the trajectory of the insert based on the calculated difference. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-212922 [Patent Document 2] Japanese Patent Application Laid-Open No. 2001-269339 Summary of the Invention [Problem to be solved by the invention]

[0005] There is a known procedure in which an inserting object is inserted into a blood vessel while checking ultrasound images of cross sections of the blood vessel and the inserting object. In such a procedure, for example, the advancement of the inserting object along the direction of the blood vessel and the translation of the ultrasound probe along the direction of the blood vessel are often repeated alternately. In this case, the entire image of the inserting object is not captured in the ultrasound image, so even when the techniques disclosed in Patent Documents 1 and 2 are used, it may be difficult for an examiner with low skill to grasp the depth to which the tip of the inserting object has reached.

[0006] The present invention has been made to solve these conventional problems, and aims to provide an ultrasound diagnostic device and a control method for an ultrasound diagnostic device that allows an examiner to easily grasp the depth to which an insert has reached when inserting an insert into a blood vessel of a subject while capturing ultrasound images showing the cross section of the blood vessel. [Means for solving the problem]

[0007] In order to achieve the above object, the ultrasound diagnostic device according to the present invention is characterized by comprising an ultrasound probe, a monitor, an image acquisition unit that acquires multiple frames of ultrasound images in which cross sections of the subject's blood vessels are continuously photographed while moving the ultrasound probe, an insertion object detection unit that detects an insertion object inserted into the subject from each of the multiple frames of ultrasound images, and a superimposition display unit that superimposes at least one insertion object detected from the multiple frames of ultrasound images by the insertion object detection unit on the latest frame of ultrasound image among the multiple frames of ultrasound images and displays the superimposed image on the monitor.

[0008] The superimposition display unit can superimpose and display at least the deepest insertion object among the multiple insertion objects detected from the multiple frames of ultrasound images. The superimposition display unit can superimpose and display a plurality of inset objects detected from a plurality of frames of ultrasound images by decreasing the brightness or saturation of inset objects detected from ultrasound images of earlier frames.

[0009] The superimposition display unit can superimpose and display only the insertion objects detected by the insertion object detection unit within a specified time range from the latest frame, out of the multiple insertion objects detected from multiple frames of ultrasound images. In addition, the superimposition display unit can also superimpose and display only the insertions, out of the multiple insertions detected from the multiple frames of ultrasound images, that are located within a specified depth range relative to the insertion detected from the latest frame of ultrasound image. In addition, the superimposition display unit can also superimpose and display only the insertions, out of the multiple insertions detected from the ultrasound images of multiple frames, that are located within a specified width range perpendicular to the depth direction of the insertion detected from the ultrasound image of the latest frame.

[0010] The ultrasound diagnostic device is equipped with an angle detection unit that detects the angle of the ultrasound probe, and the superimposed display unit can superimpose and display only the insertion object detected by the insertion object detection unit when the angle of the ultrasound probe detected by the angle detection unit is within a specified angle range.

[0011] The angle detection unit may include an angle sensor disposed on the ultrasound probe. The angle detection unit may also include an optical camera that photographs the ultrasound probe to obtain an optical image, and an optical image analysis unit that detects the angle of the ultrasound probe by analyzing the optical image obtained by the optical camera.

[0012] The ultrasound diagnostic device includes an ultrasound image analysis unit that calculates the brightness change rate of multiple insertions detected from multiple frames of ultrasound images, and the superimposition display unit can superimpose and display only insertions whose brightness change rate calculated by the ultrasound image analysis unit is within a specified range. The ultrasound diagnostic device also includes an ultrasound image analysis unit that calculates the rate of change of the background image excluding the inserted object in multiple frames of ultrasound images, and the superimposition display unit can superimpose and display only the inserted object detected from the ultrasound image of a frame in which the rate of change of the background image calculated by the ultrasound image analysis unit is within a specified range.

[0013] The ultrasound diagnostic device is equipped with a tip detection unit that detects the tip of an insert detected from multiple frames of ultrasound images by the insert detection unit, and the superimposition display unit can also superimpose and display only the tip of the insert detected by the tip detection unit.

[0014] The control method for an ultrasound diagnostic device according to the present invention is characterized in that it comprises: acquiring a plurality of frames of ultrasound images in which cross sections of blood vessels of a subject are successively photographed while moving an ultrasound probe; detecting an insertion object inserted into the subject from each of the plurality of frames of ultrasound images; and superimposing at least one of the insertion objects detected from the plurality of frames of ultrasound images on the latest frame of ultrasound image among the plurality of frames of ultrasound images and displaying the superimposed image on a monitor. [Effects of the Invention]

[0015] According to the present invention, an ultrasound diagnostic device comprises an ultrasound probe, a monitor, an image acquisition unit that acquires multiple frames of ultrasound images in which the cross section of the subject's blood vessel is continuously captured while moving the ultrasound probe, an insertion object detection unit that detects an insertion object inserted into the subject from each of the multiple frames of ultrasound images, and a superimposition display unit that superimposes at least one insertion object detected from the multiple frames of ultrasound images by the insertion object detection unit on the latest frame of ultrasound image among the multiple frames of ultrasound images and displays the superimposed image on the monitor.Therefore, when an insertion object is inserted into the blood vessel while capturing ultrasound images showing the cross section of the subject's blood vessel, the examiner can easily grasp the depth to which the insertion object has reached. [Brief explanation of the drawings]

[0016] [Figure 1] 1 is a block diagram showing the configuration of an ultrasound diagnostic apparatus according to a first embodiment of the present invention. [Figure 2] 1 is a block diagram showing a configuration of a transmission / reception circuit according to a first embodiment of the present invention. [Figure 3] FIG. 2 is a block diagram showing a configuration of an image generating unit according to the first embodiment of the present invention. [Figure 4] 3 is a diagram showing an example of the positional relationship between an ultrasonic probe and an insertion object according to the first embodiment of the present invention. FIG. [Figure 5] FIG. 2 is a diagram schematically showing an inserted object detected from an ultrasound image in the first embodiment of the present invention. [Figure 6] FIG. 2 is a diagram schematically showing an example of an ultrasound image on which a plurality of inset objects detected from ultrasound images of a plurality of frames are superimposed in the first embodiment of the present invention. [Figure 7] 4 is a flowchart showing the operation of the ultrasound diagnostic apparatus according to the first embodiment of the present invention. [Figure 8] FIG. 10 is a diagram schematically illustrating an example of an ultrasound image on which contours of a plurality of inset objects detected from ultrasound images of a plurality of frames are superimposed in a first modification of the first embodiment of the present invention. [Figure 9] FIG. 10 is a diagram schematically illustrating an example of an ultrasound image on which multiple figures surrounding multiple insets detected from ultrasound images of multiple frames are superimposed in a second modification of the first embodiment of the present invention. [Figure 10] FIG. 10 is a diagram showing a schematic example of an ultrasound image on which the center points of multiple insets detected from multiple frames of ultrasound images in a third variant of embodiment 1 of the present invention and the connecting lines connecting these center points are superimposed. [Figure 11] FIG. 10 is a diagram showing a schematic example of an ultrasound image on which multiple horizontal lines are superimposed, positioned at the depth positions of multiple insertions detected from multiple frames of ultrasound images in a fourth variant of embodiment 1 of the present invention. [Figure 12] FIG. 10 is a diagram schematically illustrating an example of an ultrasound image on which multiple indicators corresponding to the depth positions of multiple insertion objects detected from multiple frames of ultrasound images are superimposed in the fifth variant of embodiment 1 of the present invention. [Figure 13] FIG. 10 is a block diagram showing the configuration of an ultrasound diagnostic apparatus according to a second embodiment of the present invention. [Figure 14] FIG. 10 is a diagram showing an example of an inclined ultrasonic probe according to the second embodiment of the present invention. [Figure 15] FIG. 10 is a block diagram showing the configuration of an ultrasound diagnostic apparatus according to a third embodiment of the present invention. [Figure 16]FIG. 10 is a block diagram showing the configuration of an ultrasound diagnostic apparatus according to a fourth embodiment of the present invention. [Figure 17] FIG. 10 is a block diagram showing the configuration of an ultrasound diagnostic apparatus according to a fifth embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0017] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings. The following description of the components will be given based on a representative embodiment of the present invention, but the present invention is not limited to such an embodiment. In this specification, a numerical range expressed using "to" means a range that includes the numerical values ​​before and after "to" as the lower and upper limits. In this specification, the terms "same" and "identical" include a margin of error generally accepted in the technical field.

[0018] Embodiment 1 1 shows the configuration of an ultrasound diagnostic apparatus according to a first embodiment of the present invention. The ultrasound diagnostic apparatus includes an ultrasound probe 1 and an apparatus main body 2 connected to the ultrasound probe 1. The ultrasound diagnostic apparatus is used, for example, in a procedure in which an insert such as a puncture needle is inserted into the blood vessel of a subject, to observe the blood vessel of the subject and the insert inserted into the blood vessel.

[0019] The ultrasonic probe 1 has a transducer array 11. A transmitting / receiving circuit 12 is connected to the transducer array 11.

[0020] The device main body 2 has an image generation unit 21 connected to the transmission / reception circuit 12 of the ultrasound probe 1. A display control unit 22 and a monitor 23 are connected to the image generation unit 21, in that order. An image memory 26 is also connected to the image generation unit 21. An insertion object detection unit 24 is connected to the image memory 26. A superimposed display unit 25 is connected to the insertion object detection unit 24. The superimposed display unit 25 is connected to the display control unit 22. A measurement unit 27 is also connected to the image memory 26. A measurement result memory 28 and the display control unit 22 are connected to the measurement unit 27.

[0021] A main body control unit 29 is connected to the transmitting / receiving circuit 12, the image generating unit 21, the display control unit 22, the inserted object detecting unit 24, the superimposed display unit 25, the image memory 26, the measuring unit 27, and the measurement result memory 28. An input device 30 is also connected to the main body control unit 29.

[0022] The transmitting / receiving circuit 12 of the ultrasonic probe 1 and the image generating unit 21 of the device main body 2 constitute an image acquiring unit 41. The image generating unit 21, the display control unit 22, the inserted object detecting unit 24, the superimposed display unit 25, the measuring unit 27, and the main body control unit 29 constitute a processor 43 for the device main body 2.

[0023] The transducer array 11 of the ultrasonic probe 1 has a plurality of ultrasonic transducers arranged one-dimensionally or two-dimensionally. These ultrasonic transducers transmit ultrasonic waves in accordance with drive signals supplied from the transmission / reception circuit 12, receive ultrasonic echoes from the subject, and output signals based on the ultrasonic echoes. Each ultrasonic transducer is configured by forming electrodes on both ends of a piezoelectric element made of, for example, a piezoelectric ceramic typified by PZT (Lead Zirconate Titanate), a polymer piezoelectric element typified by PVDF (Poly Vinylidene Di Fluoride), or a piezoelectric single crystal typified by PMN-PT (Lead Magnesium Niobate-Lead Titanate).

[0024] The transmission / reception circuit 12, under the control of the main body control unit 29, transmits ultrasonic waves from the transducer array 11 and generates sound ray signals based on reception signals acquired by the transducer array 11. As shown in Fig. 2, the transmission / reception circuit 12 has a pulser 51 connected to the transducer array 11, an amplifier unit 52, an AD (Analog to Digital) converter unit 53, and a beamformer 54, which are connected in series from the transducer array 11 in this order.

[0025] The pulser 51 includes, for example, a plurality of pulse generators, and adjusts the delay amount of each drive signal and supplies it to the plurality of ultrasonic transducers of the transducer array 11 so that the ultrasonic waves transmitted from the plurality of ultrasonic transducers form an ultrasonic beam based on a transmission delay pattern selected in response to a control signal from the main body control unit 29. In this way, when a pulsed or continuous wave voltage is applied to the electrodes of the ultrasonic transducers of the transducer array 11, the piezoelectric material expands and contracts, and pulsed or continuous wave ultrasonic waves are generated from each ultrasonic transducer, and an ultrasonic beam is formed from the composite wave of these ultrasonic waves.

[0026] The transmitted ultrasonic beam is reflected by an object such as a part of the subject, and propagates toward the transducer array 11 of the ultrasonic probe 1. The ultrasonic echo propagating toward the transducer array 11 in this manner is received by each ultrasonic transducer constituting the transducer array 11. At this time, each ultrasonic transducer constituting the transducer array 11 expands and contracts upon receiving the propagating ultrasonic echo, generating a received signal which is an electrical signal, and outputs this received signal to the amplifier unit 52.

[0027] The amplifier 52 amplifies the signals input from each ultrasonic transducer constituting the transducer array 11 and transmits the amplified signals to the AD converter 53. The AD converter 53 converts the signals transmitted from the amplifier 52 into digital reception data. The beamformer 54 performs so-called reception focusing processing by delaying and adding each piece of reception data received from the AD converter 53. This reception focusing processing causes the reception data converted by the AD converter 53 to be phased and added, and a sound ray signal in which the focus of the ultrasonic echo is narrowed is acquired.

[0028] As shown in FIG. 3, the image generating unit 21 has a configuration in which a signal processing unit 55, a DSC (Digital Scan Converter) 56, and an image processing unit 57 are connected in series.

[0029] The signal processing unit 55 corrects the sound ray signals received from the transmission / reception circuit 12 for attenuation due to distance in accordance with the depth of the ultrasonic reflection position using the sound velocity value set by the main body control unit 29, and then performs envelope detection processing to generate a B-mode image signal, which is tomographic image information regarding the tissue within the subject.

[0030] The DSC 56 converts (raster converts) the B-mode image signal generated by the signal processing unit 55 into an image signal that conforms to the scanning method of a normal television signal. The image processing unit 57 performs various necessary image processing such as gradation processing on the B-mode image signal input from the DSC 56, and then sends the B-mode image signal to the display control unit 22 and the image memory 26. Hereinafter, the B-mode image signal that has been subjected to image processing by the image processing unit 57 will be referred to as an ultrasound image.

[0031] Under the control of the main body control unit 29, the display control unit 22 performs predetermined processing on the ultrasound image etc. generated by the image generation unit 21 and displays it on the monitor . The monitor 23 performs various displays under the control of the display control unit 22. The monitor 23 may include a display device such as an LCD (Liquid Crystal Display) or an organic EL display (Organic Electroluminescence Display).

[0032] The image memory 26 stores the ultrasound images generated by the image generation unit 21 under the control of the main body control unit 29. Furthermore, as will be described in detail later, the image memory 26 can store information about an insertion object detected from the ultrasound image by the insertion object detection unit 24 in association with the ultrasound image.

[0033] As the image memory 26, for example, a recording medium such as a flash memory, an HDD (Hard Disk Drive), an SSD (Solid State Drive), an FD (Flexible Disk), an MO disk (Magneto-Optical disk), an MT (Magnetic Tape), a RAM (Random Access Memory), a CD (Compact Disc), a DVD (Digital Versatile Disc), an SD card (Secure Digital card), or a USB memory (Universal Serial Bus memory) can be used.

[0034] A commonly known procedure involves capturing ultrasound images of the cross sections of a subject's blood vessel and an insert such as a puncture needle, and then inserting the insert into the blood vessel substantially along the direction of the blood vessel while checking the captured ultrasound images. Here, the cross section of the blood vessel refers to a cross section of the blood vessel that intersects with the direction of the blood vessel. Furthermore, the cross section of the insert refers to a cross section of the insert that intersects with the direction of extension of the insert.

[0035] In such a procedure, as shown in Fig. 4, advancement of the insert J along the running direction of the blood vessel B and translation of the ultrasound probe 1 on the body surface S of the subject along the running direction of the blood vessel B are usually repeated alternately. That is, after advancing the insert J into the blood vessel B along the running direction of the blood vessel B, the ultrasound probe 1 is translated on the body surface S of the subject along the running direction of the blood vessel B, and the insert J is further advanced into the blood vessel B along the running direction of the blood vessel B, and so on. In this way, advancement of the insert J and translation of the ultrasound probe 1 are often repeated alternately. As a result, an ultrasound image U is captured in which the cross section of the insert J is reflected inside the cross section of the blood vessel B, for example, as shown in Fig. 5.

[0036] The insertion object detection unit 24 analyzes multiple frames of ultrasound images U continuously generated by the image generation unit 21 while the ultrasound probe 1 is moved by the examiner, and detects an insertion object J inserted into the subject from each of the multiple frames of ultrasound images U.

[0037] The insertion object detection unit 24 can detect the insertion object J using, for example, a segmentation algorithm such as a binarization method or a watershed method. The insertion object detection unit 24 can also detect the insertion object J by storing, for example, a plurality of different template images representing cross sections of the insertion object J and searching the ultrasound image U using a so-called template matching method that uses these plurality of template images. The insertion object detection unit 24 can also detect the insertion object J using, for example, a 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 a 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).

[0038] The insertion object detection unit 24 sends information about the detected insertion object J to the superimposition display unit 25. The information about the detected insertion object J includes, for example, the position and shape of the insertion object J in the ultrasound image U. The insertion object detection unit 24 can also link the information to the ultrasound image U used in the detection process and send it to the image memory 26. The image memory 26 can store the information about the insertion object J received from the insertion object detection unit 24 and the corresponding ultrasound image U in a linked relationship.

[0039] The superimposition display unit 25 superimposes at least one insertion J detected from the multiple consecutive frames of ultrasound images U by the insertion detection unit 24 on the latest frame of ultrasound image U among the multiple consecutive frames of ultrasound images U generated by the image generation unit 21, and displays the superimposed image on the monitor 23. Here, the multiple consecutive frames of ultrasound images U also include the latest frame of ultrasound image. For example, as shown in FIG. 6 , the superimposition display unit 25 can superimpose insertions K1, K2, K3, and K4 that are highlighted by filling in the area of ​​the insertion J detected by the insertion detection unit 24 from the multiple frames of ultrasound images U, for example, on the latest frame of ultrasound image U, and display them on the monitor 23.

[0040] The measurement unit 27, under the control of the main body control unit 29, reads out the ultrasound image U stored in the image memory 26 and measures, for example, the dimensions of the captured blood vessel B based on the read out ultrasound image U. The measurement unit 27 can perform measurements based on, for example, input operations by the examiner via the input device 30.

[0041] Measurement result memory 28 stores the results of measurement by measurement unit 27 in association with the ultrasound image U used for the measurement, under the control of main body control unit 29. As measurement result memory 28, for example, a recording medium such as a flash memory, HDD, SSD, FD, MO disk, MT, RAM, CD, DVD, SD card, or USB memory can be used.

[0042] The input device 30 accepts input operations by the examiner and sends the input information to the main body control unit 29. The input device 30 is configured by devices such as a keyboard, a mouse, a trackball, a touchpad, and a touch panel that allow the examiner to perform input operations.

[0043] The processor 43, which is composed of the image generation unit 21, display control unit 22, inserted object detection unit 24, superimposed display unit 25, measurement unit 27 and main body control unit 29 of the device main body 2, is composed of a CPU (Central Processing Unit) and a control program for causing the CPU to perform various processes, but may also be composed using an FPGA (Field Programmable Gate Array), DSP (Digital Signal Processor), ASIC (Application Specific Integrated Circuit), GPU (Graphics Processing Unit), or other ICs (Integrated Circuits), or a combination of these.

[0044] In addition, the image generation unit 21, display control unit 22, insertion object detection unit 24, superimposed display unit 25, measurement unit 27 and main body control unit 29 of the processor 43 can be partially or entirely integrated into a single CPU or the like.

[0045] Next, an example of the operation of the ultrasound diagnostic apparatus according to the first embodiment will be described with reference to the flowchart of FIG.

[0046] First, in step S1, an examiner places the ultrasound probe 1 on the body surface S of the subject, and the image acquisition unit 41 acquires an ultrasound image U. At this time, the transducer array 11 of the ultrasound probe 1 transmits an ultrasound beam into the subject, receives ultrasound echoes from within the subject, and generates received signals. The transmission / reception circuit 12 of the image acquisition unit 41 performs so-called reception focus processing on the received signals under the control of the main body control unit 29 to generate sound ray signals. The sound ray signals generated by the transmission / reception circuit 12 are sent to the image generation unit 21. The image generation unit 21 generates an ultrasound image U using the sound ray signals sent from the transmission / reception circuit 12.

[0047] Next, in step S2, the insertion object detection unit 24 analyzes the ultrasound image U acquired in step S1 and detects an insertion object J from the ultrasound image U. The insertion object detection unit 24 can detect the insertion object J using, for example, a general image recognition method such as a segmentation algorithm, template matching, machine learning, or deep learning. In addition, the insertion object detection unit 24 sends information about the detected insertion object J to the superimposition display unit 25.

[0048] In step S3, the superimposed display unit 25 determines whether or not an insertion object J has been detected by the insertion object detection unit 24 in the ultrasound image U of a predetermined N frames since the start of the ultrasound examination. Here, N, which is the predetermined number of frames, can be set to a number equal to or greater than 2. If it is determined that an insertion object J has not been detected in the ultrasound image U of the predetermined N frames, the process returns to step S1, and a new ultrasound image U is acquired.

[0049] In this manner, the processes of steps S1 to S3 are repeated until it is determined in step S3 that the insertion object J has been detected in the ultrasound images U of the predetermined N frames. While steps S1 to S3 are being repeated, the examiner translates the ultrasound probe 1 on the body surface S of the subject to acquire a plurality of consecutive frames of ultrasound images U. At this time, the ultrasound probe 1 is moved, for example, from a position overlapping the middle portion of the insertion object J to a position overlapping the tip of the insertion object J to a position beyond the tip of the insertion object J. Therefore, by repeating steps S1 to S3, for example, an ultrasound image U showing a cross section of the middle portion of the insertion object J, an ultrasound image U showing a cross section of the tip of the insertion object J, and an ultrasound image U not showing the insertion object J are acquired. Usually, the cross section closer to the tip of the insertion object J is located deeper in the ultrasound image U.

[0050] At this time, the examiner alternately translates the ultrasonic probe 1 and advances the insert J into the subject, as shown in Figure 4. As shown in Figure 4, the insert J is inserted into the subject at a slight incline toward the deeper part of the subject along the approximate running direction of the blood vessel B, so when the examiner inserts the insert J into the blood vessel B from the so-called anterior wall of the blood vessel, the tip of the insert J gradually approaches the posterior wall of the blood vessel.

[0051] As a result of repeating the processes of steps S1 to S3 in this manner, if it is determined in step S3 that an insertion J has been detected in the ultrasound image U of the predetermined N frames, the process proceeds to step S4.

[0052] In step S4, the superimposed display unit 25 determines at least one insert J to be displayed on the monitor 23 from among the multiple inserts J detected by repeating steps S1 to S3. The superimposed display unit 25 can determine, for example, all inserts J detected by repeating steps S1 to S3 as the inserts J to be displayed on the monitor 23.

[0053] In step S5, the superimposition display unit 25 superimposes the insertion object J determined in step S4 as the insertion object J to be displayed on the monitor 23 on the latest frame of the ultrasound image U. For example, as shown in Fig. 6, the superimposition display unit 25 can display the insertion objects K1, K2, K3, and K4 detected from the ultrasound image U of multiple frames on the monitor 23 by highlighting them, for example by filling them in a color different from other areas in the ultrasound image U.

[0054] In this way, the history of the depth positions of the implants K1, K2, K3, and K4 detected in multiple frames of ultrasound image U, i.e., the implant J inserted into the subject, is superimposed on the latest frame of ultrasound image U, allowing the examiner to easily grasp the depth position of the implant J currently inserted into the subject. Furthermore, as the examiner advances the implant J inside the subject, the tip of the implant J gradually approaches the posterior wall of the blood vessel. By checking the implants K1, K2, K3, and K4 superimposed on the ultrasound image U and grasping the depth position of the implant J, the examiner can easily adjust the advancement of the implant J to prevent accidents such as the implant J penetrating the posterior wall of the blood vessel.

[0055] When the process of step S5 is completed in this manner, the operation of the ultrasonic diagnostic apparatus according to the flowchart of FIG. 7 ends.

[0056] As described above, according to the ultrasound diagnostic apparatus of embodiment 1, the insertion object detection unit 24 detects an insertion object J inserted into the subject from each of multiple consecutive frames of ultrasound images U acquired by the image acquisition unit 41, and the superimposition display unit 25 superimposes at least one insertion object J detected from the multiple frames of ultrasound images U on the latest frame of ultrasound image U and displays it on the monitor 23. Therefore, when inserting an insertion object J into the subject's blood vessel B while capturing ultrasound images U showing a cross section of the blood vessel B, the examiner can easily grasp the depth to which the insertion object J has reached. Therefore, the examiner can reliably advance the insertion object J to an appropriate position in the blood vessel B and can also prevent accidents such as the insertion object J penetrating the blood vessel B.

[0057] Although the image generating unit 21 has been described as being provided in the device main body 2, it may also be provided in the ultrasound probe 1 instead of in the device main body 2.

[0058] Furthermore, in step S4, the superimposed display unit 25 determines at least the deepest one of the multiple insertion objects K1, K2, K3, and K4 detected by the insertion object detection unit 24 from multiple frames of ultrasound image U as the insertion object J to be displayed on the monitor 23, and in step S5, the insertion object J determined in this manner can be superimposed on the latest frame of ultrasound image U. This allows the examiner to easily understand the depth range in which the insertion object J currently inserted into the subject is located.

[0059] The superimposition display unit 25 can also superimpose and display the multiple insertions K1, K2, K3, and K4 detected from multiple frames of ultrasound image U by the insertion detection unit 24 on the latest frame of ultrasound image U by lowering the brightness or saturation of the insertions K1, K2, K3, and K4 detected from the previous frame of ultrasound image U, i.e., the ultrasound image U of a frame acquired in the past. This allows the examiner to easily confirm the chronological order in which the multiple insertions K1, K2, K3, and K4 superimposed on the ultrasound image U were detected, and to easily confirm the direction of progression of the insertion J in the depth direction.

[0060] In this case, in step S4, the superimposed display unit 25 determines, among the multiple insertion objects K1, K2, K3, and K4 detected by the insertion object detection unit 24 from multiple frames of ultrasound image U, only those that have been detected by the insertion object detection unit 24 within a predetermined time range from the time the latest frame was acquired, as insertion objects J to be displayed on the monitor 23, and in step S5, the insertion object J determined in this manner can be superimposed on the latest frame of ultrasound image U. This allows the examiner to easily understand the depth range in which the insertion object J currently inserted into the subject is located.

[0061] In addition, in step S4, the superimposition display unit 25 determines, as the insertion J to be displayed on the monitor 23, only the insertions K1, K2, K3 and K4 detected by the insertion detection unit 24 from the ultrasound image U of multiple frames, and the insertions located within a specified depth range relative to the insertion K1 detected from the ultrasound image U of the latest frame, and can also superimpose the insertion J determined in this manner on the ultrasound image U of the latest frame in step S5.

[0062] The superimposition display unit 25 can set, for example, a range that is located at the center of the depth direction of the ultrasound image U and has predetermined dimensions in the depth direction as the predetermined depth range. In addition, the superimposition display unit 25 can also detect a blood vessel B from the ultrasound image U using a method such as template matching, and set, as the predetermined depth range, a range from one end to the other end of the blood vessel B in the depth direction. In this way, even when only inserts located within a specified depth range are displayed, the examiner can easily understand the depth range in which the insert J currently inserted into the subject is located.

[0063] Furthermore, the superimposition display unit 25 determines as the insert J to be displayed on the monitor 23 only the multiple inserts K1, K2, K3 and K4 detected by the insert detection unit 24 from the ultrasound image U of multiple frames, and only the inserts located within a specified width range in the width direction perpendicular to the depth direction relative to the insert K1 detected from the ultrasound image U of the latest frame, and can also superimpose the insert J determined in this manner on the ultrasound image U of the latest frame in step S5.

[0064] The superimposing display unit 25 can set the predetermined width range to, for example, a range located at the center of the width direction of the ultrasound image U and having a predetermined dimension in the width direction. The superimposing display unit 25 can also detect a blood vessel B from the ultrasound image U using a method such as template matching, and set the range from one end to the other end of the blood vessel B in the width direction as the predetermined width range. Normally, when inserting an insert J into a blood vessel B, the tip of the insert J is located within the range from one end to the other end of the blood vessel B in the width direction. Therefore, even if only inserts located within the predetermined width range are displayed, the examiner can easily grasp the depth range of the insert J currently inserted into the subject.

[0065] It has also been described that the inserts K1, K2, K3 and K4 detected by the insert detection unit 24 from multiple frames of ultrasound image U are highlighted on the monitor 23 by being filled in with a color different from other parts of the ultrasound image U, but the method of displaying the inserts K1, K2, K3 and K4 is not particularly limited to this.

[0066] 8, the superimposition display unit 25 can also superimpose contour lines K5, K6, K7, and K8 of the insertions detected by the insertion detection unit 24 from the ultrasound image U of the latest frame as representing the insertions, respectively, on the ultrasound image U of the latest frame. In this case, the insertion J detected from the ultrasound image U of the latest frame is not obscured, so the examiner can clearly grasp the current position of the insertion J.

[0067] 9, the superimposition display unit 25 can also superimpose a plurality of figures K9, K10, K11, and K12 surrounding the inserts detected by the insert detection unit 24 from the ultrasound image U of the latest frame as representing the inserts respectively, on the ultrasound image U of the latest frame. In the example of FIG. 9, rectangular figures K9, K10, K11, and K12 are superimposed on the ultrasound image U of the latest frame. In this case, the insert J detected in the ultrasound image U of the latest frame is not obscured, so the examiner can clearly grasp the position of the current insert J. Note that the shapes of the figures K9, K10, K11, and K12 are not particularly limited as long as they do not obscure the insert J detected in the ultrasound image U of the latest frame.

[0068] 10, the superimposition display unit 25 can also superimpose center points K13, K14, K15, and K16 of the insertions detected by the insertion object detection unit 24 from multiple frames of ultrasound image U onto the latest frame of ultrasound image U as representing the insertions. In this case, the insertion object J detected from the latest frame of ultrasound image U is not obscured, so the examiner can clearly grasp the current position of the insertion object J. The superimposition display unit 25 can also display a connection line L connecting the multiple center points K13, K14, K15, and K16 to one another on the latest frame of ultrasound image U. By checking the connection line L, the examiner can easily grasp the trajectory of the insertion object J's progression in the depth direction and reliably advance the insertion object J to an appropriate position within the blood vessel B.

[0069] 11, the superimposition display unit 25 can also superimpose a plurality of horizontal lines K17, K18, K19, and K20 arranged at the depth positions of the insertions detected by the insertion detection unit 24 from the plurality of frames of ultrasound image U onto the latest frame of ultrasound image U. The examiner can easily grasp the depth position of the insertion J by checking the plurality of horizontal lines K17, K18, K19, and K20.

[0070] 12, the superimposition display unit 25 can also superimpose a plurality of indicators K21, K22, K23, and K24, which are arranged at the depth positions of the insertions detected by the insertion object detection unit 24 from the plurality of frames of ultrasound image U, on the latest frame of ultrasound image U. In this case as well, the examiner can easily grasp the depth position of the insertion object J by checking the plurality of horizontal lines K17, K18, K19, and K20.

[0071] Embodiment 2 When inserting an insert J into a blood vessel B of a subject while observing an ultrasound image U of a cross section of the blood vessel B, it is preferable to acquire an ultrasound image U representing a cross section that is approximately perpendicular to the running direction of the blood vessel B so that the examiner can accurately grasp the depth position of the insert J. Therefore, the ultrasound diagnostic device can superimpose the detected insert J on the ultrasound image U only when the angle of the ultrasound probe 1 is within a predetermined angle range, for example.

[0072] 13 shows the configuration of an ultrasonic diagnostic apparatus according to embodiment 2. The ultrasonic diagnostic apparatus according to embodiment 2 includes an ultrasonic probe 1A instead of the ultrasonic probe 1 and a device main body 2A instead of the device main body 2 of the ultrasonic diagnostic apparatus according to embodiment 1 shown in FIG.

[0073] The ultrasonic probe 1A is the ultrasonic probe 1 according to the first embodiment to which an angle sensor 61 is added. The device main body 2A is the same as the device main body 2 in embodiment 1, except that it includes a main body control unit 29A instead of the main body control unit 29. The superimposed display unit 25 of the device main body 2A is connected to the angle sensor 61 of the ultrasound probe 1A. The image generation unit 21, the display control unit 22, the inserted object detection unit 24, the superimposed display unit 25, the measurement unit 27, and the main body control unit 29A form a processor 43A for the device main body 2A.

[0074] 14, the angle sensor 61 of the ultrasonic probe 1A is a sensor that detects the angle A of the ultrasonic probe 1A. For example, the angle sensor 61 can detect the angle A at which the ultrasonic probe 1A is tilted, with the angle A being 0 degrees when the tip of the ultrasonic probe 1A is pointing vertically downward. The angle sensor 61 can be configured with a known sensor device, such as a so-called acceleration sensor or a so-called gyro sensor.

[0075] The superimposition display unit 25 determines whether the angle A of the ultrasound probe 1A detected by the angle sensor 61 is within a predetermined angle range, and if the angle A is within the angle range, it can superimpose and display only the insertion object J detected by the insertion object detection unit 24 on the ultrasound image U of the latest frame. At this time, the superimposition display unit 25 can set an angle serving as a reference for the predetermined angle range, i.e., a central angle in the predetermined angle range, based on, for example, an input operation by the examiner via the input device 30. In this case, the predetermined angle range is a certain angle range based on the central angle. As a result, only the insertion object J detected from the ultrasound image U representing a cross-sectional plane substantially perpendicular to the running direction of the subject's blood vessel B can be superimposed and displayed on the ultrasound image U.

[0076] As described above, according to the ultrasonic diagnostic apparatus of the second embodiment, the superimposition display unit 25 superimposes on the ultrasonic image U of the latest frame only the insertion object J detected by the insertion object detection unit 24 when the angle A of the ultrasonic probe 1A is within a predetermined angle range. In other words, only the insertion object J detected from the ultrasonic image U representing the cross section substantially perpendicular to the running direction of the blood vessel B of the subject is superimposed on the ultrasonic image U. Therefore, the examiner can accurately grasp the actual depth position of the insertion object J by checking the insertion object J superimposed on the ultrasonic image U.

[0077] Although an example has been described in which a reference angle for a predetermined angle range is set based on an input operation by the examiner via the input device 30, the superimposed display unit 25 can also set the angle A of the ultrasound probe 1 at a point in time when a predetermined time, such as several seconds, has elapsed since the start of the ultrasound examination as the reference angle. This saves the examiner time and effort in setting the reference angle of the ultrasound probe 1, allowing the examiner to perform the ultrasound examination smoothly.

[0078] Furthermore, although it has been described that the angle detection unit that detects the angle A of the ultrasonic probe 1A is composed of the angle sensor 61, the angle detection unit may also include a relative angle calculation unit (not shown) that calculates the relative angle between the ultrasonic probe 1A and anatomical structures in the subject, such as blood vessels B and nerves, based on the angle A of the ultrasonic probe 1A detected by the angle sensor 61 and the ultrasonic image U. For example, the relative angle calculation unit can calculate the angle between the ultrasonic probe 1A and the direction in which the blood vessels B and nerves in the subject run on the cross-sectional plane represented by the ultrasonic image U, assuming that the depth direction of the ultrasonic image U is the orientation of the ultrasonic probe 1A. Based on the angle calculated in this manner and the angle A of the ultrasonic probe 1A detected by the angle sensor 61, the relative angle calculation unit can calculate the relative angle between the ultrasonic probe 1A and anatomical structures in the subject, such as blood vessels B and nerves.

[0079] Here, when the relative angle between the ultrasonic probe 1A and the running direction of the blood vessel B is calculated, the superimposed display unit 25 can set the reference angle of the determined angle range to, for example, 90 degrees. As a result, when inserting the insertion object J into the blood vessel B of the subject, the insertion object J detected on the ultrasound image U representing a cross section substantially perpendicular to the running direction of the blood vessel B is displayed on the monitor 23, allowing the examiner to accurately grasp the actual depth position of the insertion object J.

[0080] Furthermore, when inserting an insert J into a blood vessel B of a subject, an ultrasound image U representing a cross section perpendicular to the direction in which the insert J extends may be acquired in order to clearly capture the image of the insert J. Therefore, the relative angle calculation unit can also calculate the relative angle between the ultrasound probe 1A and the insert J based on the angle A of the ultrasound probe 1A detected by the angle sensor 61 and the ultrasound image U. In this case, the superimposed display unit 25 can set the reference angle of the determined angle range to, for example, 90 degrees in order to display the insert J detected from the ultrasound image U in which the insert J is clearly captured on the monitor 23.

[0081] Embodiment 3 In the second embodiment, the angle sensor 61 is used as the angle detection unit that detects the angle A of the ultrasonic probe 1A, but the configuration of the angle detection unit is not particularly limited to this as long as it can detect the angle A of the ultrasonic probe 1A. For example, the angle detection unit may have a configuration that detects the angle A of the ultrasonic probe 1A by analyzing an optical camera that captures an optical image of the ultrasonic probe 1A.

[0082] 15 shows the configuration of an ultrasonic diagnostic apparatus according to embodiment 3. The ultrasonic diagnostic apparatus according to embodiment 3 is configured by adding an optical camera 62 to the ultrasonic diagnostic apparatus according to embodiment 1 shown in FIG. 1 and including a device main body 2B instead of the device main body 2.

[0083] The device main body 2B is similar to the device main body 2 in embodiment 1 except that an optical image analysis unit 63 is added and a main body control unit 29B is provided instead of the main body control unit 29. In the device main body 2B, an optical camera 62 and the main body control unit 29B are connected to the optical image analysis unit 63. The optical image analysis unit 63 is also connected to the superimposition display unit 25. The image generation unit 21, the display control unit 22, the inserted object detection unit 24, the superimposition display unit 25, the measurement unit 27, the main body control unit 29B, and the optical image analysis unit 63 form a processor 43B for the device main body 2B. The optical camera 62 and the optical image analysis unit 63 of the device main body 2B form an angle detection unit 44.

[0084] The optical camera 62 includes an image sensor such as a so-called CCD (Charge Coupled Device) image sensor or a so-called CMOS (Complementary Metal-Oxide-Semiconductor) image sensor, and captures an optical image by photographing the ultrasound probe 1. The optical camera 62 sends the captured optical image to the optical image analysis unit 63.

[0085] The optical image analysis unit 63 detects the angle A of the ultrasound probe 1 by analyzing the optical image acquired by the optical camera 62. For example, the optical image analysis unit 63 can detect an absolute angle as angle A, with a vertical downward angle set to 0 degrees, based on the orientation of the ultrasound probe 1 in three-dimensional space. For example, the optical image analysis unit 63 can also detect a relative angle as angle A, which is the angle between the ultrasound probe 1 and the subject's body surface S, by analyzing the relationship between the ultrasound probe 1 and the subject's body surface S in the optical image.

[0086] The optical image analysis unit 63 stores, for example, a plurality of different template images representing the ultrasound probe 1, and searches the optical image by a so-called template matching method using these plurality of template images to detect the ultrasound probe 1 and detect the angle A of the detected ultrasound probe 1. The optical image analysis unit 63 can also detect the ultrasound probe 1 and detect the angle A of the ultrasound probe 1 using, for example, a 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 a 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).

[0087] Similar to the superimposition display unit 25 in embodiment 2, the superimposition display unit 25 determines whether the angle A of the ultrasound probe 1 detected by the optical image analysis unit 63 is within a specified angle range, and if the angle A is within that angle range, it can superimpose only the insertion J detected by the insertion detection unit 24 on the ultrasound image U of the latest frame.

[0088] As described above, according to the ultrasound diagnostic device of the third embodiment, when the angle A of the ultrasound probe 1 detected by the angle detection unit 44 is within a predetermined angle range, the superimposition display unit 25 superimposes only the insertion object J detected by the insertion object detection unit 24 on the ultrasound image U of the latest frame. Therefore, the examiner can accurately grasp the actual depth position of the insertion object J by checking the insertion object J superimposed on the ultrasound image U, in the same manner as in the second embodiment.

[0089] The angle detection unit 44 may also include a relative angle calculation unit (not shown) that calculates the relative angle between the ultrasound probe 1 and anatomical structures within the subject, such as blood vessels B and nerves, based on, for example, the angle A of the ultrasound probe 1 detected by the optical image analysis unit 63 and the ultrasound image U. The relative angle calculation unit can calculate the angle between the ultrasound probe 1A and the direction in which the blood vessels B and nerves within the subject run on the cross-sectional plane represented by the ultrasound image U, assuming that the depth direction of the ultrasound image U is the orientation of the ultrasound probe 1A. The relative angle calculation unit can calculate the relative angle between the ultrasound probe 1A and anatomical structures within the subject, such as blood vessels B and nerves, based on the angle calculated in this manner and the angle A of the ultrasound probe 1A detected by the optical image analysis unit 63.

[0090] Here, when the relative angle between the ultrasonic probe 1 and the running direction of the blood vessel B is calculated, the superimposed display unit 25 can set the reference angle of the determined angle range to, for example, 90 degrees. As a result, when inserting the insertion object J into the blood vessel B of the subject, the insertion object J detected on the ultrasound image U representing a cross-sectional plane approximately perpendicular to the running direction of the blood vessel B is displayed on the monitor 23, allowing the examiner to accurately grasp the actual depth position of the insertion object J.

[0091] Furthermore, when inserting an insert J into a blood vessel B of a subject, an ultrasound image U representing a cross section perpendicular to the direction in which the insert J extends may be acquired in order to clearly capture the insert J. Therefore, the relative angle calculation unit can also calculate the relative angle between the ultrasound probe 1 and the insert J based on the angle A of the ultrasound probe 1 detected by the optical image analysis unit 63 and the ultrasound image U. In this case, the superimposition display unit 25 can set the reference angle of the determined angle range to, for example, 90 degrees in order to display the insert J detected from the ultrasound image U in which the insert J is clearly captured on the monitor 23.

[0092] Embodiment 4 When an ultrasonic beam is transmitted at an angle of 90 degrees relative to the extension direction of the insert J, the intensity of the ultrasonic echo from the insert J is higher than when the ultrasonic beam is transmitted at an angle inclined from 90 degrees. As such, it can be seen that the brightness of the ultrasonic image U of the insert J changes depending on the angle A of the ultrasonic probe 1. Furthermore, when the angle A of the ultrasonic probe 1 changes, the scanned cross section within the subject changes, and therefore the overall brightness of the background image excluding the region of the insert J from the ultrasonic image U also changes.

[0093] Therefore, the ultrasound diagnostic device can also superimpose the insert J on the ultrasound image U based on, for example, the brightness change rate of the insert J in multiple frames of ultrasound image U or the overall brightness change rate of the background image, instead of the angle A of the ultrasound probe 1.

[0094] 16 shows the configuration of an ultrasonic diagnostic apparatus according to embodiment 4. The ultrasonic diagnostic apparatus according to embodiment 4 includes a device body 2C instead of the device body 2 in the ultrasonic diagnostic apparatus according to embodiment 1 shown in FIG. 1. The device body 2C is configured by adding an ultrasound image analysis unit 64 to the device body 2 in embodiment 1 and including a body control unit 29C instead of the body control unit 29.

[0095] In the device main body 2C, an ultrasound image analysis unit 64 is connected to the insertion object detection unit 24 and the image memory 26. The ultrasound image analysis unit 64 is also connected to the superimposed display unit 25 and the main body control unit 29C. The image generation unit 21, the display control unit 22, the insertion object detection unit 24, the superimposed display unit 25, the measurement unit 27, the main body control unit 29C, and the ultrasound image analysis unit 64 form a processor 43C for the device main body 2C.

[0096] The ultrasound image analysis unit 64 analyzes the multiple frames of ultrasound images U generated by the image generation unit 21, acquires the brightness of each image of an insert J detected from the multiple frames of ultrasound images U by the insert detection unit 24, and calculates the brightness change rate of the images of the multiple detected inserts J. The ultrasound image analysis unit 64 can, for example, calculate the average brightness of the area representing the insert J as the brightness of the image of the insert J included in each ultrasound image U.

[0097] The ultrasound image analysis unit 64 can also analyze multiple frames of ultrasound images U generated by the image generation unit 21, acquire the luminance of background images other than the insertion J detected by the insertion detection unit 24 in the multiple frames of ultrasound images U, and calculate the rate of change in luminance of the acquired multiple background images. The ultrasound image analysis unit 64 can, for example, calculate the average value of the overall luminance of the background images as the luminance of each background image.

[0098] Here, since the brightness change rate of the image of the insert J changes depending on the angle range of the ultrasound probe 1, by using the brightness of the image of the insert J at angle A of the ultrasound probe 1, which can capture a cross-sectional plane perpendicular to the running direction of the blood vessel B, as a reference, and acquiring an ultrasound image U so that the brightness change rate of the image of the insert J is within a specified range, it is possible to acquire an ultrasound image U representing a cross-sectional plane that is approximately perpendicular to the running direction of the blood vessel B.

[0099] In addition, the brightness change rate of the background image, like the brightness change rate of the image of the insert J, also changes depending on the angle range of the ultrasound probe 1. Therefore, by using the brightness of the background image at angle A of the ultrasound probe 1, which can capture a cross-sectional surface perpendicular to the direction of travel of the blood vessel B, as a reference, and acquiring an ultrasound image U so that the brightness change rate of the background image is within a specified range, it is possible to acquire an ultrasound image U representing a cross-sectional surface that is approximately perpendicular to the direction of travel of the blood vessel B.

[0100] Therefore, the superimposition display unit 25 can superimpose and display only the insertion object J whose brightness change rate calculated by the ultrasound image analysis unit 64 is within a predetermined range on the latest frame of ultrasound image U. At this time, the superimposition display unit 25 can set the predetermined range of the brightness change rate based on, for example, the brightness of the insertion object J in the ultrasound image U acquired at an arbitrary angle A of the ultrasound probe 1 or the brightness of the background image, based on an input operation by the examiner via the input device 30. This allows only the insertion object J detected from the ultrasound image U representing a cross section substantially perpendicular to the running direction of the subject's blood vessel B to be superimposed and displayed on the ultrasound image U.

[0101] Thus, according to the ultrasound diagnostic device of embodiment 4, when the brightness change rate calculated by the ultrasound image analysis unit 64 is within a specified range, the superimposition display unit 25 superimposes only the insertion object J detected by the insertion object detection unit 24 on the ultrasound image U of the latest frame. Therefore, the examiner can accurately grasp the actual depth position of the insertion object J by checking the insertion object J superimposed on the ultrasound image U, as in embodiments 2 and 3.

[0102] Fifth embodiment 4, the implant J is inserted into the subject at a slight incline toward the deeper part of the subject along the approximate running direction of the blood vessel B, and therefore, as the examiner advances the implant J, the tip of the implant J gradually approaches the so-called posterior wall of the blood vessel. Therefore, in order to allow the examiner to grasp the depth position of the tip of the implant J and to prevent accidents such as the tip of the implant J penetrating the posterior wall of the blood vessel, the ultrasound diagnostic device can also superimpose the tip of the implant J on the ultrasound image U of the latest frame.

[0103] 17 shows the configuration of an ultrasonic diagnostic apparatus according to embodiment 5. The ultrasonic diagnostic apparatus according to embodiment 5 includes a device main body 2D instead of the device main body 2 in the ultrasonic diagnostic apparatus according to embodiment 1 shown in FIG. 1. The device main body 2D is the same as the device main body 2 in embodiment 1 except that a tip detection unit 65 is added, and a main body control unit 29D is provided instead of the main body control unit 29.

[0104] In the device main body 2D, a tip detection unit 65 is connected to the insertion object detection unit 24. The tip detection unit 65 is also connected to the superimposed display unit 25 and the main body control unit 29D. The image generation unit 21, the display control unit 22, the insertion object detection unit 24, the superimposed display unit 25, the measurement unit 27, the main body control unit 29D, and the tip detection unit 65 form a processor 43D for the device main body 2D.

[0105] The tip detection unit 65 detects the tip of the insert J detected from multiple frames of ultrasound images U by the insert detection unit 24. Here, when multiple frames of ultrasound images U are captured while the ultrasound probe 1 moves parallel from the middle of the insert J toward the tip while the position of the insert J is fixed within the subject, ultrasound images U showing the cross section of the insert J are obtained up to a certain point, but ultrasound images U not showing the insert J are obtained from that point on. In this case, it can be determined that the insert J shown in the ultrasound image U of the frame immediately before the insert J disappears from the multiple consecutive frames of ultrasound images U represents the tip of the insert J. Therefore, the tip detection unit 65 can detect, for example, the insert J shown in the ultrasound image U of the frame immediately before the insert J detected by the insert detection unit 24 disappears from the multiple consecutive frames of ultrasound images U as the tip of the insert J.

[0106] Furthermore, since the tip of the puncture needle is sharp and has a different shape from the middle part, the brightness pattern of the tip of the puncture needle and the brightness pattern of the middle part are different from each other. Therefore, when the insertion object J is a puncture needle, the tip detection unit 65 acquires the brightness pattern of the insertion object J detected by the insertion object detection unit 24 for multiple consecutive frames of ultrasound image U, and can detect the tip of the insertion object J by analyzing the acquired brightness pattern.

[0107] In this case, the tip detection unit 65 stores, for example, a plurality of template patterns representing the brightness pattern of the tip of the insert J, and can detect the tip of the insert J by a template matching method using these plurality of template patterns. In addition, the tip detection unit 65 can also detect the tip of the insert J by 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 a 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).

[0108] The superimposed display unit 25 can superimpose and display only the tip of the insertion object J detected by the tip detection unit 65 on the ultrasound image U of the latest frame.

[0109] As described above, according to the ultrasonic diagnostic apparatus of the fifth embodiment, the tip detection unit 65 detects the tip of the insert J, and the superimposition display unit 25 superimposes only the detected tip of the insert J on the ultrasonic image U of the latest frame. Therefore, by checking the insert J superimposed on the ultrasonic image U, the examiner can easily grasp the depth position of the tip of the insert J, thereby preventing accidents such as the tip of the insert J penetrating the posterior wall of a blood vessel.

[0110] Although the aspect of the fifth embodiment has been described as being applied to the first embodiment, it can also be applied to the second to fourth embodiments. That is, the ultrasonic diagnostic devices of the second to fourth embodiments can be provided with the tip detecting unit 65 in the same manner as the ultrasonic diagnostic device of the fifth embodiment. [Explanation of symbols]

[0111] 1,1A Ultrasound probe, 2,2A,2B,2C,2D Device main body, 11 Transducer array, 12 Transmitting and receiving circuit, 21 Image generation unit, 22 Display control unit, 23 Monitor, 24 Insertion detection unit, 25 Superimposed display unit, 26 Image memory, 27 Measurement unit, 28 Measurement result memory, 29,29A,29B,29C,29D Main body control unit, 30 Input device, 41 Image acquisition unit, 43,43A,43B,43C,43D Processor, 51 Pulser, 52 Amplification unit, 53 AD conversion unit, 54 Beam former, 55 Signal processing unit, 56 DSC, 57 Image processing unit, 61 Angle sensor, 62 Optical camera, 63 Optical image analysis unit, 64 Ultrasound image analysis unit, 65 Tip detection unit, A Angle, B Blood vessel, J,K1,K2,K3,K4 Inserts, K5,K5,K6,K7 contour lines, K9,K10,K11,K12 shapes, K13, K14, K15, K16 center points, K17, K18, K19, K20 horizontal lines, K21, K22, K23, K24 indicators, L connecting line, S body surface, U ultrasound image.

Claims

1. an ultrasound probe; The monitor and an image acquisition unit that acquires a plurality of frames of ultrasound images of cross sections of blood vessels of a subject successively while moving the ultrasound probe; an insertion object detection unit that detects an insertion object inserted into the subject from each of the plurality of frames of ultrasound images; a superimposition display unit that superimposes the plurality of insertion objects detected from the ultrasound images of the plurality of frames by the insertion object detection unit on the ultrasound image of the latest frame among the ultrasound images of the plurality of frames by decreasing the brightness or saturation of the insertion objects detected from the ultrasound images of the past frames and displays the superimposed image on the monitor; An ultrasound diagnostic device comprising:

2. 2. The ultrasound diagnostic device according to claim 1, wherein the superimposition display unit superimposes and displays only the insertions detected by the insertion detection unit within a predetermined time range from the latest frame, among the multiple insertions detected from the multiple frames of ultrasound images.

3. 2. The ultrasound diagnostic device according to claim 1, wherein the superimposition display unit superimposes and displays only the insertions, among the plurality of insertions detected from the plurality of frames of ultrasound images, that are located within a predetermined depth range relative to the insertions detected from the ultrasound image of the latest frame.

4. 4. The ultrasound diagnostic device according to claim 3, wherein the superimposition display unit superimposes and displays only the insertions, among the plurality of insertions detected from the plurality of frames of ultrasound images, that are located within a predetermined width range perpendicular to the depth direction of the insertions detected from the ultrasound image of the latest frame.

5. an angle detection unit that detects the angle of the ultrasonic probe; 5. The ultrasound diagnostic device according to claim 1, wherein the superimposed display unit superimposes and displays only the insertion object detected by the insertion object detection unit when the angle of the ultrasound probe detected by the angle detection unit is within a predetermined angle range.

6. The ultrasonic diagnostic apparatus according to claim 5 , wherein the angle detection unit includes an angle sensor disposed on the ultrasonic probe.

7. The angle detection unit an optical camera that captures an optical image by photographing the ultrasound probe; an optical image analysis unit that detects the angle of the ultrasound probe by analyzing the optical image acquired by the optical camera; The ultrasonic diagnostic apparatus according to claim 5 ,

8. an ultrasound image analysis unit that calculates a brightness change rate of the plurality of insertions detected from the plurality of frames of ultrasound images; 5. The ultrasound diagnostic device according to claim 1, wherein the superimposition display unit superimposes and displays only the insert whose brightness change rate calculated by the ultrasound image analysis unit is within a predetermined range.

9. an ultrasound image analysis unit that calculates a rate of change of a background image other than the inserted object in the ultrasound images of the plurality of frames; The ultrasound diagnostic device according to any one of claims 1 to 4, wherein the superimposition display unit superimposes and displays only the insertion detected from the ultrasound image of a frame in which the rate of change of the background image calculated by the ultrasound image analysis unit is within a predetermined range.

10. a tip detection unit that detects the tip of the insertion object detected from the plurality of frames of ultrasound images by the insertion object detection unit; 10. The ultrasonic diagnostic apparatus according to claim 1, wherein the superimposed display unit displays in a superimposed manner only the tip of the insertion object detected by the tip detection unit.

11. While moving the ultrasound probe, a plurality of frames of ultrasound images are continuously acquired, each of which captures a cross section of the subject's blood vessel; Detecting an object inserted into the subject from each of the plurality of frames of ultrasound images; The plurality of inset objects detected from the plurality of frames of ultrasound images are superimposed on the latest ultrasound image of the plurality of frames of ultrasound images with brightness or saturation reduced as the inset objects detected from the ultrasound images of the previous frames are displayed on a monitor. A method for controlling an ultrasound diagnostic device.

Images