JP2009131420A - Ultrasonic image diagnosing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce the effect of movement of hands in a heart beat synchionizing three-dimensional scanning method. <P>SOLUTION: A wide range of the three-dimensional region S0 of a subject is divided to set a plurality of three-dimensional sub-regions S1-S4 and three-dimensional scanning regions P1-P4 having sizes, in which the end parts of the adjacent three-dimensional sub-regions are contained, are further set centering around these respective three-dimensional sub-regions. Then, ultrasonic transmission and reception is performed with respect to those three-dimensional scanning regions to collect a plurality of sub-volume data Vd1-Vd4. Subsequently, correlational operation is adapted to the sub-volume data of a region wherein the adjacent three-dimensional scanning regions are overlapped with each other to detect the relative positional shift of those sub-volume data and the sub-volume data are further synthesized on the basis of the positional data of the three-dimensional scanning regions corrected on the basis of the positional shift to form the volume data over a wide range of the three-dimensional scanning regions. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an ultrasonic diagnostic imaging apparatus, and more particularly to an ultrasonic diagnostic imaging apparatus that enables collection of volume data for a wide range of three-dimensional regions by applying a heartbeat-synchronized three-dimensional scanning method.

  An ultrasonic diagnostic imaging apparatus transmits and receives ultrasonic waves in multiple directions of a subject using an ultrasonic probe in which a plurality of vibration elements are arranged, and monitors image data generated based on the reflected waves obtained at this time It is what is displayed above. This device can observe 2D image data and 3D image data in the body in real time with a simple operation by simply bringing the tip of the ultrasound probe into contact with the body surface. Widely used in

  In conventional three-dimensional scanning for the purpose of collecting three-dimensional image data, an ultrasonic probe in which a plurality of vibration elements are arranged one-dimensionally is moved or rotated in a direction perpendicular to the arrangement direction of the subject. Three-dimensional image data has been generated by transmitting / receiving ultrasonic waves to / from a three-dimensional region and rendering the volume data collected at this time. In recent years, an ultrasonic probe (two-dimensional array ultrasonic probe) in which a plurality of vibration elements are two-dimensionally arranged has been put into practical use. By using this two-dimensional array ultrasonic probe, all transmission and reception of ultrasonic waves to and from the three-dimensional region can be performed electronically, so the time required for three-dimensional scanning is greatly reduced and the operability in inspection is significantly improved. did.

  However, when collecting three-dimensional data (volume data) by transmitting / receiving ultrasonic waves to / from a desired three-dimensional region, it is necessary to repeat a large number of transmission / receptions, and the time required for each transmission / reception propagates through the body of the subject. Therefore, a large amount of time is required for collecting volume data with excellent spatial resolution.

  On the other hand, a method for improving the real-time property of image data by a so-called parallel simultaneous reception method that simultaneously receives reflected waves from a plurality of directions in a subject has been developed. By applying this method to the above-described three-dimensional scanning, It is possible to reduce the time required for collecting volume data. However, three-dimensional scanning of an organ with pulsatile movement such as the heart requires a large number of parallel receptions, and there is a problem that the circuit configuration of the apparatus becomes extremely complicated in order to realize this. .

  In order to solve such a problem, a three-dimensional region including a diagnosis target part of a subject is divided into a plurality of three-dimensional subregions, and time-series volume data collected from these three-dimensional subregions ( In the following, a heartbeat-synchronized three-dimensional scanning method (Triggered Volume Scan) that synthesizes sub-volume data) based on the heartbeat time phase has been proposed (for example, see Patent Document 1).

In the above-described method, three-dimensional scanning of a predetermined period (for example, one heartbeat period) is sequentially performed on a plurality of three-dimensional subareas constituting the three-dimensional area, and heartbeat time phase information is added to the subvolume data obtained at this time. Add and save once. When the collection of sub-volume data for a plurality of three-dimensional sub-regions is completed, the volume data of the three-dimensional regions in each heartbeat time phase is generated by synthesizing the sub-volume data collected in the same heartbeat time phase. Further, the volume data is processed to generate three-dimensional image data such as time-series volume rendering image data and MPR (Multi Planar Reconstruction) image data in a desired slice cross section, thereby obtaining the diagnosis target region. It is possible to observe three-dimensional information in a desired heartbeat time phase as a moving image or a still image.
US Pat. No. 6,544,175

  As described above, the sub-volume data collected from each of the three-dimensional sub-regions by applying the heart-beat synchronized three-dimensional scanning method is synthesized based on the heartbeat time phase information, so that time-series for a wide range of three-dimensional regions is obtained. Volume data can be generated.

  However, when the relative position of the ultrasound probe with respect to the subject changes due to camera shake or the like when sequentially collecting sub-volume data in a plurality of three-dimensional sub-regions while synchronizing the heartbeat, it differs from the preset three-dimensional sub-region. Sub-volume data is collected in the area. For this reason, when generating three-dimensional image data or MPR image data based on the volume data obtained by synthesizing these sub-volume data, discontinuous areas are generated in these image data, and the image quality deteriorates. It had the problem that.

  The present invention has been made in view of such conventional problems, and an object of the present invention is to sequentially collect a plurality of sub-volume data by applying a heartbeat-synchronized three-dimensional scanning method and obtain these sub-volumes. When generating time-series volume data for a wide range of three-dimensional areas by synthesizing volume data based on heartbeat time phase information, the position of the ultrasound probe changes due to camera shake during sub-volume data collection. Is to provide an ultrasonic diagnostic imaging apparatus capable of generating accurate volume data.

  In order to solve the above-described problem, an ultrasonic diagnostic imaging apparatus according to a first aspect of the present invention uses a heartbeat-synchronized three-dimensional scanning method for a plurality of three-dimensional scanning regions set for a diagnosis target region of a subject. In an ultrasonic diagnostic imaging apparatus that applies and collects volume data in a wide range of three-dimensional regions of the subject, the three-dimensional ultrasound of the subject is overlapped so that ends of adjacent three-dimensional scanning regions overlap each other. Scanning control means for controlling scanning; sub-volume data generating means for generating sub-volume data based on a reception signal obtained by ultrasonic transmission / reception for each of the three-dimensional scanning areas; and The relative position of the sub-volume data based on the two-dimensional data or the three-dimensional data of the sub-volume data corresponding to the overlapping area Is characterized by comprising a positional displacement detecting means for detecting, and a volume data generation means for generating position correction is volume data by combining the sub-volume data was based on the detected the positional shift of.

  According to a third aspect of the present invention, there is provided an ultrasonic image diagnostic apparatus according to the present invention, wherein a heartbeat-synchronized three-dimensional scanning method is applied to a plurality of three-dimensional scanning regions set by dividing a three-dimensional region including a diagnosis target part of a subject. In an ultrasonic diagnostic imaging apparatus that applies and collects volume data in a wide range of three-dimensional regions of the subject, scanning control means for controlling three-dimensional scanning of ultrasonic waves with respect to the plurality of three-dimensional scanning regions, and the three-dimensional Sub-volume data generating means for generating sub-volume data based on a reception signal obtained by ultrasonic transmission / reception with respect to the scanning area, and two-dimensional of the sub-volume data corresponding to the boundary area in each of the adjacent three-dimensional scanning areas A positional deviation detecting means for detecting a relative positional deviation of the sub-volume data based on data or three-dimensional data; It is characterized in that a volume data generation unit generates volume data by combining the sub-volume data position correction based on the positional deviation.

  According to the present invention, a plurality of sub-volume data is sequentially collected by applying a heart-beat synchronized three-dimensional scanning method, and the obtained sub-volume data is synthesized based on heartbeat time phase information to obtain a wide range of three-dimensional data. When generating time-series volume data for an area, accurate volume data can be generated even when the position of the ultrasound probe changes due to camera shake or the like during collection of sub-volume data. Accordingly, it is possible to improve the image quality of the three-dimensional image data and MPR image data generated based on the volume data.

  Embodiments of the present invention will be described below with reference to the drawings.

  In the embodiments of the present invention to be described below, first, a wide range of three-dimensional regions with respect to a diagnosis target region of a subject are divided at predetermined intervals in a predetermined direction to set a plurality of three-dimensional subregions. A region (hereinafter, referred to as a three-dimensional scanning region) having a size including the end of each adjacent three-dimensional sub region is set with each sub region as a center. Then, each of these three-dimensional scanning regions is subjected to a three-dimensional scan for a predetermined heartbeat period to collect a plurality of subvolume data. Next, a cross-correlation operation is applied to sub-volume data collected from areas where adjacent three-dimensional scanning areas overlap each other (hereinafter referred to as overlapping areas) to detect relative positional deviation of these sub-volume data. In addition, volume data for the wide-range three-dimensional area is generated by synthesizing the sub-volume data based on the position information of the three-dimensional scanning area corrected based on the positional deviation.

  In the following embodiments, B-mode data is generated by processing a reception signal obtained by transmitting / receiving ultrasonic waves to / from the above-described three-dimensional scanning region, and a sub-volume of the three-dimensional scanning region is generated based on this B-mode data. Although the case where data is generated will be described, sub-volume data may be generated based on other ultrasonic data such as color Doppler data.

(Device configuration)
The configuration and basic operation of the ultrasonic diagnostic imaging apparatus according to the embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a block diagram showing the overall configuration of the ultrasonic diagnostic imaging apparatus, and FIGS. 2 and 5 show the transmission / reception unit / reception signal processing unit and subvolume data generation unit of the ultrasonic diagnostic imaging apparatus. It is a block diagram which shows a specific structure.

  The ultrasonic diagnostic imaging apparatus 100 shown in FIG. 1 transmits an ultrasonic pulse (transmission ultrasonic wave) to a three-dimensional region in which a diagnosis target part of a subject is arranged, and an ultrasonic reflected wave (transmission ultrasonic wave) obtained by this transmission ( An ultrasonic probe 3 in which a plurality of vibration elements for converting received ultrasonic waves into electrical signals (received signals) are two-dimensionally arranged, and a drive signal for transmitting ultrasonic pulses in a predetermined direction of the subject And transmitting / receiving unit 2 for phasing and adding reception signals of a plurality of channels obtained from these oscillating elements, and a receiving signal for processing the received signals after phasing and adding to generate B-mode data The B-mode data collected in the three-dimensional scanning region centered on each of the processing unit 4 and the plurality of three-dimensional subregions set for the three-dimensional region of the subject is position information on the three-dimensional scanning region. And heartbeat time phase information And a sub-volume data generating unit 5 for generating a sub-volume data stored in correspondence to the ultrasonic transmitting and receiving direction.

  In addition, the ultrasonic diagnostic imaging apparatus 100 performs a cross-correlation operation on the overlapping area of the sub-volume data generated in each of the adjacent three-dimensional scanning areas, and detects a relative positional shift between these sub-volume data. A positional deviation detection unit 6; a positional information correction unit 7 that corrects positional information of a three-dimensional scanning region attached to the sub-volume data based on the positional deviation; and a corrected positional information of the three-dimensional scanning region. A volume data generation unit 8 that synthesizes a plurality of sub-volume data based on the above heartbeat time phase information to generate volume data for a wide range of three-dimensional regions, and an MPR based on the volume data supplied from the volume data generation unit 8 An image data generation unit 9 that generates image data and three-dimensional image data, and an image data generation unit 9 And a display unit 10 for displaying the PR image data and three-dimensional image data.

  Furthermore, the ultrasonic diagnostic imaging apparatus 100 inputs subject information, sets subvolume data generation conditions and image data generation conditions, sets a three-dimensional area, sets a region of interest for subvolume data, and inputs various command signals. An input unit 11 for performing transmission and reception, and a scanning control unit 12 for performing control for transmitting and receiving ultrasonic waves to and from a three-dimensional scanning region set around a plurality of three-dimensional subregions, Further, the biological signal measurement unit 13 that measures the electrocardiogram waveform of the subject, the heartbeat time phase detection unit 14 that detects the heartbeat time phase based on the electrocardiogram waveform, and the above-described units are centrally controlled. A system control unit 15 is provided.

  The ultrasonic probe 3 has M vibrating elements (not shown) arranged two-dimensionally at its tip, and transmits and receives ultrasonic waves by bringing the tip into contact with the body surface of the subject. The vibration element is an electroacoustic transducer, which converts an electric pulse (drive signal) into an ultrasonic pulse (transmitted ultrasonic wave) at the time of transmission, and converts an ultrasonic reflected wave (received ultrasonic wave) into an electric reception signal at the time of reception. It has the function to convert to. Each of these vibration elements is connected to the transmission / reception unit 2 via an M channel multi-core cable (not shown). In the present embodiment, an ultrasonic diagnostic imaging apparatus 100 using the sector scanning ultrasonic probe 3 in which M vibrating elements are two-dimensionally arranged will be described. However, ultrasonic waves corresponding to linear scanning, convex scanning, and the like are described. A probe may be used.

  Next, the transmission / reception unit 2 illustrated in FIG. 2 includes a transmission unit 21 that supplies a drive signal to the vibration element of the ultrasonic probe 3 and a reception unit that performs phasing addition on the reception signal obtained from the vibration element. 22 is provided.

  The transmission unit 21 includes a rate pulse generator 211, a transmission delay circuit 212, and a drive circuit 213. The rate pulse generator 211 generates a rate pulse that determines a repetition period of the transmission ultrasonic wave and transmits the transmission delay circuit 212. To supply. The transmission delay circuit 212 is composed of the same number of independent delay circuits as the Mt number of vibration elements used for transmission, and a focusing delay time for focusing the transmission ultrasonic wave to a predetermined depth and a predetermined direction (θp, A deflection delay time for transmission to φq) is given to the rate pulse and supplied to the drive circuit 213. The drive circuit 213 has the same number of independent drive circuits as the transmission delay circuit 212, and Mt (Mt) selected for transmission from among the M vibration elements arranged two-dimensionally by the ultrasonic probe 3. ≦ M) Drives the vibration elements and radiates transmission ultrasonic waves into the body of the subject.

  On the other hand, the receiving unit 22 is an A / D converter of an Mr channel corresponding to Mr (Mr ≦ M) vibrating elements selected for reception from among the M vibrating elements built in the ultrasonic probe 3. 221, a reception delay circuit 222, and an adder 223. The Mr channel reception signal supplied from the reception vibration element is converted into a digital signal by the A / D converter 221, and the reception delay circuit 222 receives the signal. Sent.

  The reception delay circuit 222 has a focusing delay time for focusing the received ultrasonic wave from a predetermined depth and a deflection delay time for setting the reception directivity for a predetermined direction (θp, φq). An adder 223 adds the reception signals from the reception delay circuit 222 to each of the Mr channel reception signals output from the / D converter 221. That is, the reception delay circuit 222 and the adder 223 perform phasing addition on the reception signal obtained from a predetermined direction. In addition, the reception delay circuit 222 and the adder 223 of the reception unit 22 enable so-called parallel simultaneous reception in which reception directivities in a plurality of directions are simultaneously formed by controlling the delay time. By applying this parallel simultaneous reception method, three-dimensional The time required for scanning is greatly reduced. A part of the transmission unit 21 and the reception unit 22 included in the transmission / reception unit 2 may be provided inside the ultrasonic probe 3.

  FIG. 3 shows the ultrasonic transmission / reception direction (θp, φq) in orthogonal coordinates (xyz) with the central axis of the ultrasonic probe 3 as the z axis. In this case, the vibration element is the x axis. Two-dimensionally arranged in the direction and the y-axis direction, and θp and φq indicate angles with respect to the z-axis in the ultrasonic transmission / reception direction projected on the xz plane and the yz plane. Then, the delay times in the transmission delay circuit 212 of the transmission unit 21 and the reception delay circuit 222 of the reception unit 22 are controlled according to the scanning control signal supplied from the scanning control unit 12, and set around each of the plurality of three-dimensional sub-regions. Ultrasonic wave transmission / reception is sequentially performed on the three-dimensional scanning region of a predetermined size.

  Next, a plurality of three-dimensional sub-regions set by dividing the three-dimensional region of the subject and a three-dimensional scanning region set so that the ends overlap each other around each of these three-dimensional sub-regions This will be described with reference to FIG.

  FIG. 4A shows the three-dimensional region S0 and the three-dimensional subregions S1 to S4 set as the diagnosis target region of the subject. For example, the three-dimensional region S0 is represented by a predetermined number of subregions N (N = N = 4) Alternatively, four three-dimensional sub-regions S1 to S4 are set by dividing in the y-direction with a maximum three-dimensional sub-region width ΔS. On the other hand, FIG. 4B shows three-dimensional scanning regions P1 to P4 that are set so that the ends thereof overlap with each other of the three-dimensional subregions S1 to S4. However, in order to facilitate explanation in FIG. 4B, cut surfaces of the three-dimensional sub-regions S1 to S4 and the three-dimensional scanning regions P1 to P4 in the cross section C parallel to the yz plane of FIG. Is used to show the relationship between the three-dimensional sub-region and the three-dimensional scanning region.

  That is, in FIG. 4B, the three-dimensional sub-regions S1 to S4 having the maximum three-dimensional sub-region width ΔS are set by dividing the maximum three-dimensional region width Ry in the y direction by N (N = 4). Three-dimensional scanning regions P1 to P4 having a predetermined maximum three-dimensional scanning region width ΔP (ΔP> ΔS) are set so as to cover each of the dimensional subregions S1 to S4. Each of the three-dimensional scanning regions P1 to P4 is set so that the end thereof overlaps the end of another three-dimensional scanning region adjacent in the y direction, and is thus collected from the adjacent three-dimensional scanning region. The end of the subvolume data is formed by three-dimensional information of the same diagnosis target part. In this embodiment, the three-dimensional region at the end where adjacent three-dimensional scanning regions overlap each other is called an overlapping region, and the three-dimensional region-of-interest data set for this overlapping region is the region of interest. Called data.

  Returning to FIG. 2, the reception signal processing unit 4 has a function of generating B-mode data as ultrasonic data, and includes an envelope detector 41 and a logarithmic converter 42. The envelope detector 41 envelope-detects the reception signal after the phasing addition supplied from the adder 223 of the receiving unit 22, and the logarithmic converter 42 logarithmically converts the amplitude of the reception signal subjected to the envelope detection. To generate B-mode data. Note that the envelope detector 41 and the logarithmic converter 42 may be configured by changing the order.

  Next, a specific configuration of the sub-volume data generation unit 5 shown in FIG. 1 will be described using the block diagram of FIG. The subvolume data generation unit 5 includes an ultrasonic data storage unit 51, an interpolation processing unit 52, and a subvolume data storage unit 53.

  In the ultrasonic data storage unit 51, time-series B-mode data generated by the reception signal processing unit 4 based on the reception signal obtained by ultrasonic transmission / reception for each of the three-dimensional scanning regions is stored in the ultrasonic transmission / reception direction (θp). , Φq) are sequentially stored as supplementary information. On the other hand, the interpolation processing unit 52 forms three-dimensional B-mode data by arranging a plurality of B-mode data read from the ultrasonic data storage unit 51 in units of three-dimensional scanning regions in correspondence with the ultrasonic transmission / reception direction. Further, time-series subvolume data composed of isotropic voxels is generated by interpolating the unequally spaced voxels constituting the three-dimensional B-mode data. The above-described sub-volume data generated for each of the three-dimensional scanning areas is the position information of the three-dimensional scanning area supplied from the system control unit 15 or the heartbeat time phase detection unit 14 described later. The heartbeat time phase information of the subject is stored in the subvolume data storage unit 53 as supplementary information. However, when a positional shift occurs in the sub-volume data, the position information of the three-dimensional scanning area stored together with the sub-volume data in the sub-volume data storage unit 53 is corrected by the position information correction unit 7 described later, Position information is newly stored as incidental information of the sub-volume data. Similarly, information on the ultrasonic transmission / reception direction stored together with the B mode data in the ultrasonic data storage unit 51 is converted based on the corrected position information and newly stored as incidental information of the ultrasonic data.

  Returning to FIG. 1 again, the positional deviation detection unit 6 includes an arithmetic circuit (not shown), and is collected from, for example, the three-dimensional scanning region P2 adjacent to the subvolume data Vd1 collected from the three-dimensional scanning region P1 of FIG. The sub volume data Vd2 is read from the sub volume data storage unit 53 of the sub volume data generation unit 5. Then, a three-dimensional region of interest having a predetermined size is set for the overlapping region of the subvolume data Vd1 and the subvolume data Vd2, and the region-of-interest data extracted from the region of interest of the subvolume data Vd1 and the subvolume data Vd2 The relative positional deviation of the subvolume data Vd2 with respect to the subvolume data Vd1 is detected by the arithmetic processing. Various methods have been proposed as a positional deviation detection method for two-dimensional image data and the like. Here, the positional deviation detection method to which the cross-correlation method is applied will be described with reference to FIG.

In FIG. 6, the signal intensity (luminance) of the region-of-interest data in the three-dimensional region of interest Ro1 set in the overlapping region of the sub-volume data Vd1 collected from the three-dimensional scanning region P1 is represented by A (p, q, r ) (P = 1 to P, q = 1 to Q, r = 1 to R) Voxel signals in the overlapping region of the sub-volume data Vd2 collected from the three-dimensional scanning region P2 adjacent to the three-dimensional scanning region P1 If the intensity is B (p, q, r), the evaluation function β _AB (j, k, s) for detecting the positional deviation of the subvolume data Vd2 with respect to the subvolume data Vd1 is expressed by the following equation (1). Indicated.

Then, while sequentially moving the region of interest Ro1 set in the overlapping region of the subvolume data Vd1 in the p direction, q direction, and r direction with respect to the subvolume data Vd2, the evaluation function γ _AB (j, k, s) is calculated, and when γ _AB (j, k, s) has a peak value at j = jx, k = kx and s = sx, the subvolume data Vd2 is p with respect to the subvolume data Vd1. It is detected that the position is shifted by jx voxels in the direction, kx voxels in the q direction, and sx voxels in the r direction. However, N in the above equation (1) represents the product of the number P of voxels in the p direction, the number of voxels Q in the q direction, and the number R of voxels in the r direction in the region of interest data.

  In FIG. 6, the case where the positional deviation of the subvolume data Vd2 with respect to the subvolume data Vd1 is detected by the cross-correlation calculation between the region-of-interest data of the subvolume data Vd1 and the subvolume data Vd2 has been described. The positional deviation of the subvolume data Vd3 collected from P3 with respect to the subvolume data Vd2 and the positional deviation of the subvolume data Vd4 collected from the three-dimensional scanning region P4 with respect to the subvolume data Vd3 are also detected by the same procedure.

  On the other hand, the position information correction unit 7 in FIG. 1 reads the position information of the three-dimensional scanning region stored together with the subvolume data in the subvolume data storage unit 53 of the subvolume data generation unit 5. Next, the positional information of the three-dimensional scanning area is corrected based on the positional deviation information detected by the positional deviation detection unit 6, and the corrected positional information of the three-dimensional scanning area is stored in the subvolume data storage unit 53. That is, the position information of the three-dimensional scanning area before correction stored as the auxiliary information of the sub-volume data is updated to the position information of the corrected three-dimensional scanning area supplied from the position information correction unit 7.

  Next, the volume data generation unit 8 includes an arithmetic circuit and a volume data storage circuit (not shown). The arithmetic circuit reads the subvolume data stored in the subvolume data storage unit 53 of the subvolume data generation unit 5, the heartbeat time phase information that is the accompanying information, and the position information of the corrected three-dimensional scanning region, Based on these incidental information, a plurality of sub-volume data collected in each of the three-dimensional scanning regions is synthesized to generate time-series volume data for a wide range of three-dimensional regions. The obtained volume data is temporarily stored in the volume data storage circuit.

  The image data generation unit 9 includes an MPR image data generation unit and a three-dimensional image data generation unit (not shown). The MPR image data generation unit reads time-series volume data stored in the volume data storage circuit of the volume data generation unit 8 and selects voxels corresponding to preset MPR image sections from the volume data. Extract and generate time-series MPR image data.

  On the other hand, the three-dimensional image data generation unit has a function of rendering volume data supplied from the volume data generation unit 8 to generate three-dimensional image data such as volume rendering image data and surface rendering image data. For example, an opacity / color tone setting unit and a rendering processing unit are provided. The opacity / color tone setting unit sets the opacity and color tone of each voxel based on the voxel value of the volume data, and the rendering processing unit sets the opacity and color tone set by the opacity / color tone setting unit. The volume data is rendered based on the color tone information to generate three-dimensional image data.

  Next, the display unit 10 includes a display data generation unit, a data conversion unit, and a monitor (not shown), and the display data generation unit is a desired MPR image cross section generated in the MPR image data generation unit of the image data generation unit 9. Display data is generated by adding incidental information such as subject information to the MPR image data and the three-dimensional image data generated by the three-dimensional image data generation unit. The data converter performs D / A conversion and display format conversion on the display data generated by the display data generator and displays the display data on the monitor.

  The input unit 11 includes an input device such as a display panel, a keyboard, a trackball, a mouse, a selection button, and an input button on the operation panel, and a region-of-interest setting unit 111 that sets a region of interest for an overlapping region of sub-volume data. A three-dimensional region setting unit 112 that sets a three-dimensional region including a diagnosis target part is included. Also, input of object information, setting of subvolume data generation conditions, setting of image data generation conditions and display conditions, setting of MPR image section, setting of the number of subareas N or maximum three-dimensional subarea width ΔS, maximum 3 The setting of the dimension scanning area width ΔP and the input of various command signals are also performed using the above-described display panel and input device.

  The scanning control unit 12 applies the above-described plurality of three-dimensional scanning regions (for example, P1 to P4 in FIG. 4B) set in the three-dimensional region of the subject to which the heartbeat-synchronized three-dimensional scanning is applied. On the other hand, delay time control for sequentially performing ultrasonic transmission / reception is performed on the transmission delay circuit 212 of the transmission unit 21 and the reception delay circuit 222 of the reception unit 22.

  The biological signal measurement unit 13 has a function of measuring an electrocardiogram waveform of the subject, a measurement electrode attached to the surface of the subject body and detecting the electrocardiogram waveform, and an electrocardiogram waveform detected by the measurement electrode. And an A / D converter (both not shown) for converting the amplified electrocardiogram waveform into a digital signal.

  On the other hand, the heartbeat time phase detection unit 14 detects a heartbeat time phase based on the electrocardiogram waveform supplied from the biological signal measurement unit 13. Specifically, first, the position of the R wave is detected by measuring the peak value of the electrocardiogram waveform, and then the interval between two R waves adjacent in the time direction (RR interval) is set to a predetermined time interval. The heartbeat time phase is detected by dividing by. The information on the heartbeat time phase detected at this time is added to the subvolume data generated by the subvolume data generation unit 5 as supplementary information.

  Next, the system control unit 15 includes a CPU and a storage circuit (not shown), and the above-described various information input / set by the input unit 11 is stored in the storage circuit. Then, the CPU controls each unit of the ultrasonic image diagnostic apparatus 100 based on the input / setting information described above, sets a three-dimensional area for the diagnosis target region, a three-dimensional sub-area and a three-dimensional area for the three-dimensional area. Setting of a scanning area, collection of sub-volume data in the three-dimensional scanning area, generation of volume data by synthesis of these sub-volume data, and generation and display of three-dimensional image data based on the volume data are performed.

(Procedure for generating image data by heartbeat synchronization three-dimensional scanning method)
Next, a procedure for generating image data based on a plurality of sub-volume data collected from the subject by applying the heartbeat-synchronized three-dimensional scanning method will be described with reference to the flowchart of FIG.

  Prior to generating three-dimensional image data by the heartbeat-synchronized three-dimensional scanning method, the operator of the ultrasonic image diagnostic apparatus 100 inputs object information, sets subvolume data generation conditions, and image data generation conditions in the input unit 11. If necessary, setting of display conditions, setting of MPR image section, setting of the number of sub-regions N or maximum three-dimensional sub-region width ΔS, setting of maximum three-dimensional scanning region width ΔP, etc. are performed. These input information and setting information are stored in the storage circuit of the system control unit 15 (step S1 in FIG. 7).

  When the above initial setting is completed, the operator sets the three-dimensional area S0 of the input unit 11 to collect volume data for the diagnosis target part of the subject based on past examination data and the like. Setting is performed by the setting unit 112. The system control unit 15 that has received the setting information of the three-dimensional region S0 from the three-dimensional region setting unit 112 sets the three-dimensional region S0 to N based on the number N of subregions already set or the maximum three-dimensional subregion width ΔS. The three-dimensional sub-regions S1 to SN are divided and set (step S2 in FIG. 7), and each of the three-dimensional sub-regions S1 to SN is the center and has a maximum three-dimensional scanning region width ΔP (ΔP> ΔS). The dimension scanning areas P1 to PN are set (step S3 in FIG. 7).

  Next, the operator inputs a generation start command of 3D image data by the heartbeat synchronization 3D scanning method at the input unit 11, and the command signal is supplied to the system control unit 15 to generate 3D image data. Is displayed (step S4 in FIG. 7).

  When generating the sub-volume data for the first three-dimensional scanning region P1, the rate pulse generator 211 of the transmission unit 21 shown in FIG. 2 generates a rate pulse by dividing the reference signal supplied from the system control unit 15 To the transmission delay circuit 212. The transmission delay circuit 212 has a focusing delay time for focusing the ultrasonic wave to a predetermined depth and a deflection for transmitting the ultrasonic wave in the first ultrasonic transmission / reception direction (θ1, φ1) in the three-dimensional scanning region P1. The delay time is given to the rate pulse, and this rate pulse is supplied to the drive circuit 213 of the Mt channel. Next, the drive circuit 213 generates a drive signal based on the rate pulse supplied from the transmission delay circuit 212, and supplies this drive signal to the Mt transmitting vibration elements provided in the ultrasonic probe 3 to be covered. Transmit ultrasonic waves into the specimen.

  A part of the transmitted ultrasonic wave is reflected by the organ boundary surface or tissue of the subject having different acoustic impedance, and is received by the Mr receiving vibration elements provided in the ultrasonic probe 3 to be used in the Mr channel. It is converted into an electrical reception signal. Next, the received signal is converted into a digital signal by the A / D converter 221 of the receiving unit 22, and is further used for focusing for converging received ultrasonic waves from a predetermined depth in the Mr channel reception delay circuit 222. After the delay time and the deflection delay time for setting a strong reception directivity with respect to the received ultrasonic wave from the ultrasonic transmission / reception direction (θ1, φ1), the phasing addition is performed by the adder 223. Then, the envelope detector 41 and the logarithmic converter 42 of the received signal processing unit 4 to which the received signal after the phasing addition is supplied perform envelope detection and logarithmic conversion on the received signal to obtain B-mode data. The generated B-mode data is stored in the ultrasonic data storage unit 51 of the sub-volume data generation unit 5 with the ultrasonic transmission / reception direction (θ1, φ1) as supplementary information.

  Next, the system control unit 15 controls the delay time in the transmission delay circuit 212 of the transmission unit 21 and the reception delay circuit 222 of the reception unit 22 to sequentially update the three-dimensional scanning region by Δθ in the θ direction and Δφ in the φ direction. For each of the ultrasonic transmission / reception directions (θp, φq) of P1 (θp = θ1 + (p−1) Δθ (p = 2 to P), φq = φ1 + (q−1) Δφ (q = 2 to Q)) Three-dimensional scanning is performed by transmitting and receiving ultrasonic waves in the same procedure. The B-mode data obtained in each transmission / reception direction is also stored in the ultrasonic data storage unit 51 of the sub-volume data generation unit 5 with the above-described ultrasonic transmission / reception direction as supplementary information.

  When the generation and storage of the B-mode data for the three-dimensional scanning region P1 is completed, the interpolation processing unit 52 of the sub-volume data generation unit 5 reads a plurality of time-series B data read from the ultrasonic data storage unit 51. The mode data is made to correspond to the ultrasonic transmission / reception direction (θp, φq) (θp = θ1 + (p−1) Δθ (p = 1 to P), φq = φ1 + (q−1) Δφ (q = 1 to Q)). The three-dimensional B-mode data is formed by arranging them, and the sub-volume data Vd1 composed of isotropic voxels is generated by interpolating the non-uniformly spaced voxels constituting the three-dimensional B-mode data. To do. Next, the sub-volume data Vd1 collected in the three-dimensional scanning region P1 is obtained from the heartbeat time phase information of the subject supplied from the heartbeat time phase detection unit 14 and the three-dimensional scanning region P1 supplied from the system control unit 15. The position information is stored as supplementary information in the subvolume data storage unit 53 of the subvolume data generation unit 5 (step S5 in FIG. 7).

  Furthermore, ultrasonic waves are transmitted / received to / from the three-dimensional scanning areas P2 to PN by the same procedure to generate subvolume data Vd2 to VdN, and the obtained subvolume data Vd2 to VdN are also used for heartbeat time phase information and three-dimensional scanning areas. The position information of P2 to PN is stored as supplementary information in the subvolume data storage unit 53 of the subvolume data generation unit 5 (step S5 in FIG. 7).

  When the generation and storage of the sub-volume data Vd1 to VdN is completed, the positional deviation detection unit 6 first collects the sub-volume data Vd1 collected from the three-dimensional scanning region P1 and is collected from the adjacent three-dimensional scanning region P2. The subvolume data Vd2 is read from the subvolume data storage unit 53 of the subvolume data generation unit 5. Then, a three-dimensional region of interest having a predetermined size is set for the overlapping region of the subvolume data Vd1 and the subvolume data Vd2, and the region-of-interest data extracted from the region of interest of the subvolume data Vd1 and the subvolume data Vd2 The relative positional deviation of the sub-volume data Vd2 with respect to the sub-volume data Vd1 is detected by the cross-correlation calculation.

  Further, the subvolume data Vd2 and the subvolume data Vd3 collected from the three-dimensional scanning area P3 adjacent to the three-dimensional scanning area P2,... The subvolume data VdN-1 collected from the three-dimensional scanning area PN-1 For each of the sub-volume data VdN collected from the three-dimensional scanning region PN adjacent to the three-dimensional scanning region PN-1, a relative positional shift is detected by the same procedure as described above (step S6 in FIG. 7). .

  The position information correction unit 7 that has received the position shift information of the sub-volume data Vd2 to VdN from the position shift detection unit 6 saves the sub-volume data Vd2 to VdN together with the sub-volume data storage unit 53 of the sub-volume data generation unit 5. The position information of the three-dimensional scanning area being read is read out. Next, the position information of the three-dimensional scanning region is corrected based on the position shift information of the sub-volume data Vd2 to VdN supplied from the position shift detection unit 6, and the pre-correction 3 stored in the sub-volume data storage unit 53 is corrected. The position information of the three-dimensional scanning area is updated with the corrected position information of the three-dimensional scanning area (step S7 in FIG. 7).

  Next, the arithmetic circuit of the volume data generation unit 8 performs sub-volume data stored in the sub-volume data storage unit 53 of the sub-volume data generation unit 5 and the accompanying heartbeat time phase information and its corrected three-dimensional information. The position information of the scanning area is read out, and a plurality of sub-volume data collected in each of the three-dimensional scanning areas is synthesized based on the incidental information to generate time-series volume data for a wide range of three-dimensional areas. Then, the obtained volume data is temporarily stored in its own volume data storage circuit (step S8 in FIG. 7).

  On the other hand, the image data generation unit 9 reads time-series volume data stored in the volume data storage circuit of the volume data generation unit 8. Then, MPR image data and three-dimensional image data in a predetermined MPR image section are generated and displayed on the monitor of the display unit 10 as a moving image or a still image in a desired heartbeat time phase (step S9 in FIG. 7).

(Modification)
Next, a modification of the present embodiment will be described with reference to FIG. In the above-described embodiment, a three-dimensional sub-region composed of a plurality of three-dimensional sub-regions is set by dividing the three-dimensional region of the subject into three pieces, and each of the three-dimensional sub-regions is set as the center and the end portions thereof are overlapped. Although the case where the cross-correlation calculation is applied to the overlapping area of the sub-volume data collected from the scanning area to detect the positional deviation of the sub-volume data has been described, in this modification, the above-described three-dimensional sub-area is changed to 3 A position shift of the sub-volume data is detected by applying a cross-correlation operation to two two-dimensional data collected from the boundary surface of the adjacent three-dimensional scanning region or the vicinity thereof.

  FIG. 8A shows the three-dimensional region S0 and the three-dimensional subregions S1 to S4 set in the diagnosis target region of the subject as in FIG. 4A. For example, the three-dimensional region S0 is set as a predetermined value. The four three-dimensional subregions S1 to S4 are set by dividing in the y direction by the number of subregions N (N = 4) or the maximum three-dimensional subregion width ΔS. On the other hand, FIG. 4B shows six two-dimensional data Q1b, Q2a, Q2b collected from the three-dimensional scanning regions P1 to P4 set in the three-dimensional subregions S1 to S4 and their boundary surfaces or the vicinity thereof. Q3a, Q3b and Q4a are shown. However, in order to facilitate the description also in FIG. 8B, the three-dimensional scanning regions P1 to P4 in the cross section C parallel to the yz plane in FIG. 8A and the cut surface of the two-dimensional data are used. 2D data collected from the boundary surface of an adjacent 3D scanning region or the vicinity thereof is shown.

  That is, in FIG. 8B, the three-dimensional scanning regions P1 to P4 having the maximum three-dimensional scanning region width ΔP are set by dividing the maximum three-dimensional region width Ry in the y direction by N (N = 4). Sub-volume data Vd1 to Vd4 are generated by ultrasonic transmission / reception with respect to the three-dimensional scanning regions P1 to P4. Next, two-dimensional data Q1b and Q2a at or near the boundary surface between the three-dimensional scanning region P1 and the three-dimensional scanning region P2 are generated based on the sub-volume data Vd1 and the sub-volume data Vd2, and the obtained two-dimensional data A cross-correlation operation is applied to the data Q1b and Q2a to detect a positional shift of the subvolume data Vd2 with respect to the subvolume data Vd1.

  Similarly, the two-dimensional data Q2b, Q3a, Q3b, and Q4a at or near the boundary surface between the three-dimensional scanning region P2, the three-dimensional scanning region P3, the three-dimensional scanning region P3, and the three-dimensional scanning region P4 are sub-volume data Vd2. To Vd4. Then, a positional shift of the subvolume data Vd3 with respect to the subvolume data Vd2 is detected by the cross-correlation calculation of the two-dimensional data Q2b and the two-dimensional data Q3a, and the subvolume data Vd3 is calculated by the cross-correlation calculation of the two-dimensional data Q3b and the two-dimensional data Q4a. The positional deviation of the sub volume data Vd4 with respect to is detected.

  Note that the two two-dimensional data (for example, the two-dimensional data Q1b and the two-dimensional data Q2a) used for the cross-correlation calculation of the present modification are not collected from the same part of the subject, but from extremely close parts. Since it is collected, it can be handled as substantially the same two-dimensional data. According to this method, since the cross-correlation calculation is performed on the two-dimensional data, the time required for detecting the positional deviation is significantly shortened as compared with the above-described embodiment in which the cross-correlation calculation is performed on the three-dimensional data. Temporal continuity in the display of three-dimensional image data can be improved.

  According to the embodiment of the present invention described above, a plurality of sub-volume data are sequentially collected by applying the heartbeat-synchronized three-dimensional scanning method, and the obtained plurality of sub-volume data is synthesized based on the heartbeat time phase information. As a result, when generating time-series volume data for a wide range of three-dimensional regions, accurate volume data can be generated even when the position of the ultrasound probe changes due to camera shake during the collection of sub-volume data. . Accordingly, it is possible to improve the image quality of the three-dimensional image data and MPR image data generated based on the volume data. In addition, since re-collection of sub-volume data due to camera shake is not necessary, examination efficiency is improved and the burden on the subject and the operator is reduced.

  In particular, since the three-dimensional scanning region where the sub-volume data is collected is set so that the end thereof overlaps the end of another adjacent three-dimensional scanning region, the three-dimensional scanning region in the same diagnosis target region of the subject The cross-correlation calculation can be applied to the two sub-volume data including the information, and the relative positional deviation between the sub-volume data can be accurately detected.

  Also, the position information of the three-dimensional scanning area and the information on the ultrasonic transmission / reception direction stored together with the sub-volume data are converted based on the position information of the three-dimensional scanning area corrected based on the above-described position deviation and the position information. Therefore, when the volume data is generated by repeating or reusing these ultrasonic data and sub-volume data, the position detection of the sub-volume data and the position of the three-dimensional scanning area are performed. Information correction can be omitted. Accordingly, it is possible to reduce the time required for generating volume data.

  On the other hand, according to the above-described modification, since the cross-correlation calculation is performed on the two-dimensional data, the time required for detecting the positional deviation is greatly shortened. Accordingly, the time required for generating the volume data is further shortened, and the temporal continuity in displaying the time-series three-dimensional image data generated based on the volume data can be improved.

  As mentioned above, although the Example of this invention and its modification were described, this invention is not limited to the above-mentioned Example and its modification, It can change and implement further. For example, in the above-described embodiment, a three-dimensional region of interest is set in the overlapping region in two adjacent subvolume data, and the relative position between the subvolume data is based on the three-dimensional data obtained from this region of interest. In the case of detecting a deviation, a two-dimensional region of interest is set in a desired direction with respect to the overlapping region, and a positional deviation between sub-volume data is detected based on the two-dimensional data obtained from the region of interest. May be. According to this method, it is possible to significantly reduce the time required for detecting the positional deviation.

  In addition, the case where a three-dimensional region is set for a diagnosis target part of the subject based on past examination data has been described. However, prior to the collection of subvolume data, a two-dimensional image is obtained by a single plane method or a multiplane method. Data may be collected and the 3D region may be set based on these 2D image data, or the 3D region may be set based on provisional 3D image data collected by 3D scanning. May be.

  On the other hand, in the above-described modification, a case where a relative positional shift between sub-volume data is detected by performing a cross-correlation operation on two two-dimensional data collected from the boundary surface of adjacent three-dimensional scanning regions or the vicinity thereof. As described above, the positional deviation between the sub-volume data may be detected by performing a cross-correlation operation on two three-dimensional data collected from the boundary surface of the three-dimensional scanning region or its vicinity.

  Furthermore, in the above-described embodiment and its modification, the method for detecting the relative positional deviation between the sub-volume data by applying the cross-correlation method has been described. However, the difference value between the sub-volume data is calculated, and this difference is calculated. Applying other methods such as a method of detecting the amount of movement of the region of interest that minimizes the sum of absolute values or the sum of squares (referred to here as the difference sum minimum method) and the entropy method between sub-volume data The positional deviation may be detected.

1 is a block diagram showing the overall configuration of an ultrasound diagnostic imaging apparatus according to an embodiment of the present invention. The block diagram which shows the specific structure of the transmission / reception part with which the ultrasonic diagnostic imaging apparatus of the Example is provided, and a received signal processing part. The figure for demonstrating the ultrasonic transmission / reception direction in the three-dimensional scanning of the Example. The figure for demonstrating the several three-dimensional sub area | region with respect to the three-dimensional area | region of the Example, and the three-dimensional scanning area | region set based on these three-dimensional sub areas. The block diagram which shows the specific structure of the subvolume data generation part with which the ultrasonic diagnostic imaging apparatus of the Example is provided. The figure for demonstrating the position shift detection of the subvolume data by the cross correlation method of the Example. The flowchart which shows the production | generation procedure of the image data by the heart rate synchronous three-dimensional scanning method of the Example. The figure for demonstrating the modification of the Example.

Explanation of symbols

2. Transmission / reception unit 21 ... Transmission unit 211 ... Rate pulse generator 212 ... Transmission delay circuit 213 ... Drive circuit 22 ... Reception unit 221 ... A / D converter 222 ... Reception delay circuit 223 ... Adder 3 ... Ultrasonic probe 4 ... Received signal processing unit 41 ... envelope detector 42 ... logarithmic converter 5 ... subvolume data generation unit 51 ... ultrasonic data storage unit 52 ... interpolation processing unit 53 ... subvolume data storage unit 6 ... position shift detection unit 7 ... position Information correction unit 8 ... volume data generation unit 9 ... image data generation unit 10 ... display unit 11 ... input unit 111 ... region of interest setting unit 112 ... three-dimensional region setting unit 12 ... scanning control unit 13 ... biological signal measurement unit 14 ... heartbeat Time phase detector 15 ... system controller 100 ... ultrasonic diagnostic imaging apparatus

Claims (9)

An ultrasonic diagnostic imaging apparatus that collects volume data in a wide range of three-dimensional regions of the subject by applying a heartbeat-synchronized three-dimensional scanning method to a plurality of three-dimensional scanning regions set for a region to be diagnosed of the subject In
Scanning control means for controlling the three-dimensional scanning of the ultrasonic wave on the subject so that the end portions of the adjacent three-dimensional scanning regions overlap each other;
Sub-volume data generating means for generating sub-volume data based on a reception signal obtained by ultrasonic transmission / reception for each of the three-dimensional scanning regions;
A positional deviation detecting means for detecting a relative positional deviation of the sub-volume data based on two-dimensional data or three-dimensional data of the sub-volume data corresponding to an overlapping area of the adjacent three-dimensional scanning area;
An ultrasonic diagnostic imaging apparatus comprising: volume data generation means for generating volume data by synthesizing the sub-volume data whose position is corrected based on the detected positional deviation.   The scanning control means includes the three-dimensional scanning including an end portion of an adjacent three-dimensional sub-region, with each of a plurality of three-dimensional sub-regions set by dividing a wide three-dimensional region of the subject as a reference The ultrasonic diagnostic imaging apparatus according to claim 1, wherein the three-dimensional scanning of the region is controlled. Collection of volume data in a wide range of three-dimensional regions of the subject by applying a heartbeat-synchronized three-dimensional scanning method to a plurality of three-dimensional scanning regions set by dividing a three-dimensional region including a diagnosis target part of the subject In the ultrasonic diagnostic imaging apparatus,
Scanning control means for controlling three-dimensional scanning of ultrasonic waves for the plurality of three-dimensional scanning regions;
Subvolume data generation means for generating subvolume data based on a reception signal obtained by ultrasonic transmission / reception with respect to the three-dimensional scanning region;
Position shift detection means for detecting a relative position shift of the sub-volume data based on two-dimensional data or three-dimensional data of the sub-volume data corresponding to a boundary region in each of the adjacent three-dimensional scan areas;
An ultrasonic diagnostic imaging apparatus comprising: volume data generation means for generating volume data by synthesizing the sub-volume data whose position is corrected based on the detected positional deviation.   Position information correction means for correcting position information of the three-dimensional scanning area based on the position shift is provided, and the volume data generation means converts the sub-volume data based on the corrected position information of the three-dimensional scanning area. The ultrasonic image diagnostic apparatus according to claim 1 or 3, wherein the volume data is generated by synthesis.   Receiving signal processing means for processing a reception signal obtained by ultrasonic transmission / reception with respect to the three-dimensional scanning region and generating at least one of B-mode data and color Doppler data as ultrasonic data; and the sub-volume data generation means The ultrasonic image diagnostic apparatus according to claim 1, wherein the sub-volume data is generated based on the ultrasonic data generated by the reception signal processing means.   The positional deviation detection means is one of a cross-correlation method, a difference sum minimum method, and an entropy method for two-dimensional data or three-dimensional data of sub-volume data corresponding to an overlapping region or boundary region of the adjacent three-dimensional scanning region. The ultrasonic image diagnostic apparatus according to claim 1, wherein a relative positional shift of the sub-volume data is detected by applying the sub-volume data.   A region-of-interest setting unit is provided for setting a region of interest for the subvolume data corresponding to an overlapping region or boundary region of the adjacent three-dimensional scanning region, and the positional deviation detecting unit is configured to detect from the region of interest of the subvolume data. 4. The ultrasonic diagnostic imaging apparatus according to claim 1, wherein a relative positional shift of the sub-volume data is detected based on the obtained two-dimensional data or three-dimensional data.   The sub-volume data generation means includes ultrasonic data storage means for storing the ultrasonic data using information on the ultrasonic transmission / reception direction with respect to the three-dimensional scanning region as supplementary information, and the position information correction means includes the ultrasonic data 5. The ultrasonic diagnostic imaging apparatus according to claim 4, wherein the information on the ultrasonic transmission / reception direction stored in the storage unit is updated based on the corrected position information of the three-dimensional scanning region.   The sub-volume data generation means includes sub-volume data storage means for storing the sub-volume data using the position information of the three-dimensional scanning area as supplementary information, and the position information correction means is stored in the sub-volume data storage means 5. The ultrasonic diagnostic imaging apparatus according to claim 4, wherein the position information of the three-dimensional scanning area that has been updated is updated to the position information of the corrected three-dimensional scanning area.

Images