JPS62500283A - Ultrasound diagnostic equipment - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] Super 111u fake Naomata Cultivation and growth The present invention relates generally to ultrasonic diagnostic devices, and more particularly to superimposed anatomical information and The present invention relates to a device capable of displaying blood flow rate information and blood flow rate information.

! eastern cunning blood Ultrasound diagnostic equipment provides comprehensive information on physical health and disease. Ultrasonic method is that It has been proven safe and effective and is therefore widely available to both patients and physicians. Accepted ultrasound diagnostic equipment uses very high frequency sound waves (typically 3.0 M on the order of Hz) and then analyze the waves reflected from body structures. generates an image of the internal structure of the body. Probably the most widely used ultrasound The diagnostic device displays structural information of the organ in the form of a two-dimensional image of a selected cross section of the organ. Ru. The ultrasound waves are typically scanned across the organ in the form of a fan scan. The sector scan is Usually done in real time so that images are obtained during the examination. In such cases, the organ The movement of causes a correspondingly moving image.

In cardiology, most diseases are associated with both anatomical and blood flow abnormalities. There is. Two-dimensional anatomical images include, for example, mitral stenosis, intracardiac shunts, and wall motion abnormalities. Although it has been proven to be very effective in detecting aortic stenosis, It is less effective for evaluating mitral valve and aortic insufficiency and congenital defects. do not have. Within these latter regions, anatomical defects are extremely small and often It exceeds the resolution of conventional anatomical ultrasound equipment. However, due to the lack of these Information regarding blood flow abnormalities caused by this is very important. Therefore, if blood These anomalies can be more easily detected if the flow can be monitored.

Several currently available ultrasound devices use the Doppler principle to provide blood source information. provide Typical Dotsupura ultrasound devices include the Ii, Numa, and other U.S. No. 4.318.413 and tleubscher and other rice It is disclosed in National Patent No. 4.324.258. A beam of ultrasonic energy , blood source information is directed to the desired blood vessel or other organ. moving blood wA vesicles reflects the ultrasonic energy and also directs the reflected energy according to the Doppler principle. This causes an increase or decrease in frequency depending on the direction of blood flow. Lease flow speed The magnitude of the frequency shift and the direction of the shift can be detected such that the magnitude and direction of the shift can be detected. be done. Such Doppler ultrasound devices typically use conventional ultrasound diagnostic methods. It also provides anatomical information.

Currently used Doppler ultrasound devices are disadvantageous in many respects. Probably the most A significant disadvantage is that such devices cannot be used to target one point or several individual points within an organ. However, it is only possible to provide information on blood sources in the area. Blood flow is often within an organ, Even within a relatively small body canal, blood is not uniformly distributed, so using such a device, complete blood It is difficult to obtain original information.

The present invention overcomes the above-mentioned limitations of Doppler ultrasound devices. disclosed Ultrasound diagnostic equipment that uses real-time two-dimensional images superimposed on real-time two-dimensional anatomical images Provides a dimensional blood image. Blood origin information can be obtained at a single point or multiple points in an organ. rather than being displayed across the entire organ or its major parts. It will be done. Therefore, the examiner can xylemically inspect the entire cross-section of the organ or a portion thereof at a single point in time. The above and other advantages of the present invention, in which blood source information can be obtained over a wide range of Together, they will become apparent to those skilled in the art from the description of the best mode for carrying out the invention.

Matatomo 9-Jou An ultrasonic diagnostic device for displaying two-dimensional surface liquid flow information is disclosed. This device is , sends a series of ultrasound bursts directed at areas of the patient where blood source information needs to be obtained. Contains a transducer array for output. Ultrasound achieves fan-shaped scanning feed in multiple directions within a given plane, typically 30 different directions, so that Served.

The ultrasound reflected from the blood is received by a transducer array and processed accordingly. is converted into an electrical signal. The reflected ultrasonic waves are transmitted to each emitted ultrasonic beam. sampled periodically during the reception period following the start. Sampled reflected ultrasound signal The signal is a detector circuit that detects the frequency difference between the transmitted and received ultrasound waves. supplied to The output of the detector circuit contains in-phase and quadrature components. It is preferable to do so.

A processor unit receives frequency difference data from the detector circuit and, in response, Generates a speed estimator signal. These estimation signals are for each beam direction. Indicates the blood flow velocity at multiple points along the beam. There are typically 174. Detected from 5 bursts of transmitted ultrasound waves Preferably, each velocity estimator signal is generated from the data The number of hosts may be greater or less than five.

The estimation signal is then sent to a display such as a color television monitor. Given. Formatting speed estimator data from sector scan to standard rask scan Preferably, a scan converter memory is used to convert the matte. Di The spray typically images the blood flow leaving the transducer array on one side. For example, the image of the blood flow that occurs in red and goes to the transducer array is shown on the other side. occurs in colors such as blue. The intensity of the color is adjusted according to the magnitude of blood flow velocity. It is sectioned.

M plate■Full hair lump plate Figure 1 shows a typical image generated by the ultrasonic diagnostic apparatus according to the present invention. FIG. 3 shows the corresponding positions of the generated ultrasound transmitter/receiver probes;

FIGS. 2A and 2B are block diagrams of an ultrasonic diagnostic device according to the present invention.

FIG. 3 is a block diagram showing in more detail the processor unit of the ultrasound diagnostic apparatus according to the present invention. It is a lock diagram.

FIG. 4 is a block diagram of the coefficient multiplier section of the processor unit.

FIGS. 5A and 5B illustrate typical memory reads/writes of a processor unit. This is a timing diagram showing the embedded sequence.

Figure 6 shows the Doppler shift and speed of the processor unit of the ultrasonic diagnostic device according to the present invention. 3 is a graph showing the relationship between the magnitude of the degree estimator signal and the magnitude of the signal.

FIG. 7 is a block diagram showing in more detail the addition/display circuit of the ultrasonic diagnostic apparatus according to the present invention. This is a diagram.

The best 5 ways to avoid H Referring to FIG. 1, the ultrasonic diagnostic apparatus according to the present invention has A normal phased array connected to the main unit of diagnostic equipment (not shown) It includes an ultrasound probe 10.

The probe 10 is generally linear to form an ultrasound beam, as will be described below. The activation of a piezoelectric transducer energized by an electrical excitation in a precise time sequence. Contains ray. A sector-shaped range with a scan angle φ typically from 60° to 90° In order to swing the ultrasound beam over the surrounding area, a time delay of 1lfi is then applied to each excitation pulse. added to. yo (as is known, mainly to focus the beam , an additional small delay is added to the center element. The direction of the emitted beam Ultrasonic reflections or echoes returning from a given target are transduced at different times. reach the sa element. Therefore, the signal generated by reflection from a given point within the body An additional time delay circuit is installed in the receiver section of the device so that all of the I'm being kicked.

The fan-scan image, generally designated 14, is a color image of a television monitor. -Displayed on CRT. Image 14 is located along the transmit/receive sheet along the 11H order beam line. It is formed by performing a kensu. One such beam line is shown in Fig. 88. As will be explained in more detail below, the image data is A wave beam is generated sequentially through the fan angle φ and is also stored in the scan converter memory. As it is stored, it is retrieved. The data is then formatted into standard rask scan format. read from the scan converter memory to generate a television image using be done.

Image 14 represents typically 150 bursts of the ultrasound beam in various directions through angle φ. generated from the Each burst has a duration of approximately 8 μs. ultrasound frequency is on the order of 3 MHz, but higher resolution is required to obtain large resolution. frequencies may be used, and lower frequencies may be used to obtain greater penetration. Wave numbers may be used.

Ultrasonic bursts are typically spaced approximately 200 μs apart from each other. burst During the approximately 190 μs period in between, the probe 10 acts as a receiver. body structure and the return ultrasound reflected from the group of red blood cells for use by the blood flow processing circuit. approximately once every 1.12 μs, and approximately once every 1.12 μs to obtain anatomical information. Sampled once every s. Therefore, the reflected ultrasound waves generate a blood original image. Each burst is followed by approximately 17 Sampled 4 times. The returned ultrasound waves received earlier are the body structures and the probe 10. It is reflected from nearby blood cells. Return ultrasound waves received later are transmitted inside the body. It is a reflection from a deeper source. Amplitude and timing of reflected ultrasound waves The structure of the heart is the normal two-dimensional anatomy of the body structure, as shown in Figure 1, @, 16. Used to generate scientific image information. The device also displays body structure in white.

Movement of a reflex body, such as a group of blood cells, away from the probe 10 according to the Doppler principle increases the wavelength of the reflected ultrasound, while the movement of the body approaching the probe 10 increases the wavelength of the reflected ultrasound. Shorten the wavelength of ultrasound. The velocity of ultrasound in the tissue and the frequency of ultrasound are given. , the human blood velocity is on the order of 200 Hz to 3 kHz. This causes plastic deviation. 64 beams through angle φ to form scanned image 14 All five ultrasonic bursts are generated to yield velocity information at points along the wave direction. be done. The color and intensity of the image are adjusted according to the direction and speed of the flow. plow Velocity ti for the blood flow leaving the tube? The information is shown in red and the other probe is Velocity information for blood flow is shown in blue. The greater the speed, the brighter the image. The degree is large. Thus, for example, the original image of blood in the region 18 adjacent to the aortic valve is The blood flow in this region leaves the probe 10 at a relatively high velocity, so the bright red It is.

The ultrasound device according to the present invention can superimpose blood source information over the entire fan-shaped scanned image 14. However, it is usually preferable to display such information only for a portion of the scan angle φ. stomach. The anatomical data portion of the image typically consists of 128 beams of pixels for the entire scan. It is formed. A complete scan of blood flow data consists of 64 booms of pixels. but , since the rate at which blood flow pixel data is generated is relatively low, a full scan of blood flow data The images produced by the camera tend to flicker. Such flicker is used However, it is usually acceptable to change the scan angle of the blood source information to the anatomical scan angle φ. It is preferable to limit it to a portion. For example, approximately 1/2 of the anatomical scan angle The blood flow scan angle, the angle that includes 30 beams of pixel data, substantially reduces fluff. do. To obtain the benefits of the present invention, blood original images spanning at least two beam directions are required. data should be used, but in order to obtain a more complete image Preferably, the direction is used. The magnitude of the scan angle that generates blood source information is determined by the operation. can be controlled by a controller. In addition, the depth of blood source information is part of the anatomical data. can be reduced to minutes. For example, if anatomical information up to 15 cm deep inside the body is displayed, the operator can select the blood source image to improve the characteristics of the blood source image. The processing of information may be limited to 100. Similarly, when an operator processes blood flow data, Suitable controls (not shown) are provided to adjust the maximum depth to which the Referring to FIGS. 2A and 2B, an ultrasonic device according to the present invention has a includes a reference oscillator 20 providing a 3.0 Mllz output signal. Reference frequency The number is chosen to be the operating frequency of the transducer probe. to the reference oscillator A connected pulse generator 24 generates a series of bursts or 3.0 MHz signals. generates a pulse. The duration of an individual burst is typically 0.66 μs. , the series of bursts does not last more than 8 μs. A series of bursts here called bursts Pulses are generated every 200 μs.

The output of the pulse generator 24 provides phase adjustment between the plurality represented by block 26. Connected to the regular array pulser circuit. Typically 48 pulser circuits are installed. I'm being kicked. Each pulser circuit has a digitally selected delay. each pal The output end of the sensor circuit is connected to each individual transducer array arranged inside the probe O. The piezoelectric transducer 28 is connected to each piezoelectric transducer 28 . The piezoelectric transducer is Converts 3MHy, burst or pulse generated by circuit 26 into ultrasound do. is swung over an angle ψ to produce a standard fan-shaped scan image 14 (FIG. 1). To generate a series of beams of ultrasonic waves, the delay of the individual pulser circuits is Controlled by a control circuit (not shown).

Piezoelectric transducer 28 includes a plurality of receivers represented by block 28. It is also connected to the circuit. 2. During the 190 μs period between ultrasound transmissions. transduyu The sensor 28 acts as an ultrasonic receiver and converts reflected ultrasonic waves into electrical signals. exchange. An electrical signal is controlled for the output of each transducer 28 of probe 10. A delay/adder circuit 30 is provided which provides a controllable delay and sums the outputs.

As is well known, signals generated by ultrasound reflections from a single source within the body simultaneously Each transducer of the phased transducer array is processed to It is necessary to selectively delay the signals generated by the sensor. Figure 7 shows the delay/ Adder circuit 30 is shown in more detail. of transducer 28 on conductor 29 48 output terminals are connected to the preamplifier aS circuit 33, respectively. Output of amplifier 33 The output end is connected to a variable short time delay circuit 31, and this variable short time delay circuit 31 is connected to each The delay of circuit 3] is selectively controlled from 0 to 0.32 m5 by a control device (not shown). It has a digital control input that allows it to be changed.

48 short delay times 1i! 331 output terminals each have 24 output terminals each. The analog multiplexer 32 is connected to one of the 48 analog multiplexers 32 that exist. Each circle A multiplexer is a multiplexer in which the analog signal at the input is routed to the 24 outputs of the multiplexer. and a control input (not shown) for connection to a selected one of the. Ma Each of the 2 and 2 outputs of the multiplexer is connected to a tap of the delay line 19. Ru. For example, the output 0 of each multiplexer is is applied to tap 0 of delay line 19.

Output 1 is provided to tap 1 of the delay line, as shown by conductor 23. . Outputs 3 to 22 (not shown) of multiplexer 32 are the taps of delay line 19. 2 to 22.

Finally, the output 24 of the multiplexer, as indicated by conductor 25, Connected to tap 23 of the analog delay line.

Delay line 19 consists of 24 analog fixed delay circuits each providing a delay of 300 n, s. Contains road 27. Tap 0 of this circuit is one input of the two-power summing amplifier 25. connected to the end. The output terminal of this amplifier is connected to one input terminal of the delay circuit 27. has been done. The output terminal of the delay circuit 27 is connected to an output conductor 43 via a buffer amplifier 29. It is connected to the. Therefore, the signal on output 0 of multiplexer 32 is 19 by 300 ns.

Tap 1 of the delay line 19 is connected to one input end of the other two-power summing amplifier 25. There is. The output terminal of this amplifier 25 is passed through a second delay circuit 27 to a first summing amplifier 8. 25 second input terminal. Therefore, the multiplex supplied to tap 1 The signals from lexer output 1 are delayed by a total of 600 ns. Delay circuit 2 7 and the rest of the summing amplifier 25 are combined with taps 3 to 22 and are constructed in the same way. Finally, tap 23 on the delay line connects the other buffer It is connected to the input end of the delay circuit 27 through a width amplifier 29 . Supplied from tap 23 The signals from the output terminal 23 of the multiplexer are 7. 200ns (300n3×24).

The above embodiment of the delay/summing circuit 30 is low cost and relatively long running, on the order of 7 μs. Allow for a delay between. Short delay circuit 3 using a suitable control circuit (not shown) 1 and multiplexer 32, the reflected ultraviolet light from a given source can be The signals from the transducer 28 generated by the sound waves are summed and sent to the output conductor 4. A delay is made so that all three signals are applied at the same time.

The output terminal of the delay/addition circuit 30 is connected to the full value detection circuit 36 by the delay/addition circuit 30. It is connected. After circuit 36, the residual AC component of the signal generated by circuit 36 is A low-pass filter circuit 38 is connected to remove the components. Therefore, absolute value detection Circuit 36 together with filter circuit 38 serves as an amplitude detector. filter times The DC output of line 38 produces a digital anatomical echo signal as output 42. A flash type analog-to-digital converter 40 is provided. As is well known, Flash converters allow for rapid processing of data and typically - Does not need to be combined with an and-hold circuit. As explained next, This digital signal is used for display on black and white and color CRTs or for video tape recording. A scan that converts fan scan output to a rask scan formant for recording to a coder transferred to converter memory.

The output of the summing amplifier 34 is also supplied to the input terminals of a pair of phase detectors 42 and 44. Ru. The remaining input terminal of the detector 42 receives the 3 MHz multiplied signal from the reference generator 20. It is connected to a leading conductor 22. The remaining input terminal of the detector 44 is a phase shift circuit. 46, and this phase shift circuit is connected to the oscillator 20. times The path 46 is connected to the detector 44 at a 90° phase with respect to the reference signal applied to the detector 42. Give a shifted 3MHz signal.

The outputs of phase detectors 42 and 44 are fed to low pass filters 48 and 50, respectively. more filtered. Each filtered output is activated by a common control circuit 56. are provided to separate sample-and-hold circuits 42 and 54, which are used to perform the same operation. sa The output terminals of the sample-and-hold circuits 42 and 54 are 10-bit analog signals. - connected to the inputs of digital converter circuits 58 and 60, respectively; child These transducers are also connected to control circuit 56. Outputs of converters 58 and 60 The ends are connected to output conductors 62 and 64, respectively.

Phase detector 42 and filter 48 serve as in-phase synchronous detectors and also Phase detector 44 and filter 50 serve as a quadrature synchronous detector. system The control circuit 56 converts the signal into a 10-bit digital signal by converters 58 and 6o. The outputs of the two detectors are sampled and held periodically during the exchange. do. The digital outputs of transducers 58 and 60 each actuate probe 12. of the in-phase and quadrature components of the reflected ultrasound signal at the reference frequency, which is the frequency Represents magnitude and sign.

Referring now to FIG. 2B, the analog-to-digital transitions on conductors 62 and 64 The outputs of converters 58 and 60 are provided to a processor unit 66. More details later As will be described in detail, the processor unit 66 has an angle φ( Blood at a particular point along one of the 64 beams spaced through the Provides a velocity estimator signal representing the velocity of the flow. The speed estimator signal is are sequentially written into random access scan converter memory 70 as they are generated. be included. Digital anatomical echo signals on lead 42 are also generated as they are generated. and are sequentially written to other parts of the scan combine memory 70.

Velocity estimator signals and anatomical echo signals are standard Rusk scan formers, are read out from the scan converter memory on leads 72 and 74, respectively.

Velocity estimator and blood flow data combined with specific parts of the body are implemented. qualitatively simultaneously from separate Si b5 of the memory. speed estimation meter The signal controls a red/blue modulator circuit 76. The output end of the intermodulator circuit 76 is a composite device. It is connected to the input end of circuit 80. Anatomical data read from transducer memory The code signal is a white signal having an output terminal connected to the input/ura of the other multiplexer circuit 80. A color modulator circuit 78 is provided. The composite circuit 80 receives a conventional composite video synchronization signal. It has a third input end connected to a conductor 82 that leads to. For example, this signal Contains horizontal and vertical sync signals. A color burst signal (not shown) is also applied to the multiplexer. available. The fourth compounder input terminal is the output of the central processor unit (CPU) 83. connected to the end. The CPU 83 stores, among other things, the patient's name, medical history and and operating instructions (selected from the menu in the usual way). ). The output of the multiplexer circuit 80 is a color ray tube 84. (CRT) and a video tape recorder 86 (VTR). anatomy Physiological and blood flow data can be combined by simply summing the two signals in the combiner. It is folded. The ultrasound device of the present invention is preferably used exclusively for displaying anatomical information. Also includes a black and white television monitor. The monitor display is the second composite It includes a black and white CRT 87 driven by a camera circuit 85. One side of the compound device 85 The input terminal receives the anatomical echo data read out from the scan converter memory 70. It is connected to a lead wire 74. The second input is a conductor for carrying a composite video synchronization signal. It is connected to line 81. The third input terminal is the central processor unit (CPU) 8 Connected to 3.

Next, the method of operation of the ultrasonic diagnostic apparatus according to the present invention will be explained in more detail. the above , the pulsed beam of ultrasound energy periodically positions the probe 12. It is delivered from a phase-adjusted transducer array. The beam has a fan-shaped scanning image 14 ( 1) over an angle φ. for each of the 64 beam directions. Then, by the action of the pulse generator 24 (Fig. 2A), the probe is moved at intervals of approximately 200 μs. sends out five ultrasonic bursts. The signal is reflected ultrasound following each burst is generated at the output of the delay/adder circuit 30. If the reflected source is sent out ultrasonic If it is moving with respect to the wave, the reflected signal will reflect the velocity of the source towards the probe. There will be a frequency shift proportional to the component of . Filter 4th is reflected faith. Generates a signal with sign and magnitude that matches the component in phase with the reference frequency of the signal. The filter 50 also matches the component of the reflected signal that is in quadrature with the reference frequency. produces a signal with sign and magnitude. These analog signals are sampled hand-hold circuit 52.54 and analog-to-digital converter circuit 58.6 0 is sampled every 1.12 μs and converted to a digital signal.

Analog-digital combined with in-phase and quadrature demodulators The digital data generated by the converter 58 is indicated by XK and Ys, respectively. has been done. The subscript n varies from O to 4 and represents five ultrasonic bars along the beam direction. (beam line format) that produced the data. Superscripts are from O to 1 Which of the 174 successive samples of reflected ultrasound waves varied up to 73 Indicates whether it occurred. Thus, for example, X2 is beam line type 2 (5 berths the same position that occurred during the 61st time interval following the transmission of the third burst of Indicates the phase components.

The digital speed estimator signal at the output of the processor unit 66 is , the sign and magnitude of the blood velocity at a given point along one of the 64 beam directions. represent. As mentioned above, users typically use [flI fluid/! To improve the quality of Li The diagnostic device according to the invention was developed in order to limit the number of optical beam directions to less than 64. make a clause The signal can be negative or negative depending on the direction of blood flow relative to the probe 10. may be positive. The estemeter is represented by ■6, where The superscript also indicates the position of the blood sample along the beam line. Therefore, for example , the speed estimator ■106 was lowered slightly more than the shortcut of the statue. 1 represents the velocity of the amount of blood displayed on the image 14 of FIG. If 5 ultrasound bursts is sent out in the direction along beam line 88, for example, the resultant velocity est. Meter ■100 represents the velocity of blood flow in the region 18 adjacent to the aortic valve, the same The estimator V'30 generated by five bursts of Represents the velocity of blood flow deeper within the body.

The speed estimator V is calculated from the values Xs and Xs by the processor unit according to the formula below. Calculated by knit 66.

V” = l (X’a S o Y o T o (1) + X list S4 Y! iT+)1 + l (X 3 T o + Y’5 S.

+X)T++Yma Sl + X-curvature T4 + Y-true S4) 1 1 (X: S o + YET.

+X curvature S4+Y4T4)1 Here, ■=speed estimator, k one time interval (0 to 173), X-fjtK In-phase component of li device output data, Y = quadrature phase component of demodulator output data, 5o =1, S+=4.52=6.53=-4,54-1, T o = -2, T + = 4, T2 = 0, T1 = -4, T4 = 2゜ Next, with reference to FIG. We will further explain how the calculations are expressed. The processor unit 66 has a calculation speed Because of the requirements for It is realized using logical elements. The particular implementation of the processor is part of the invention. However, based on the disclosure of this specification, those skilled in the art can easily implement it in various ways. can be expressed. In order to avoid obscuring the essence of the present invention with unnecessary detailed description, The operation of the processor unit 66 will be explained in terms of its functions.

The same phase components XMId are shown by block 92 in FIG. is multiplied by a constant coefficient Sn or Tn so that Similarly, the quadrature component YA is also These coefficients are multiplied as indicated by block 94. The result and The respective products of are then added together as shown by block 96. and is applied to a second adder 98. Adders 96 and 98 both subtract Can perform calculations. The remaining input terminal of adder 98 is connected to the output terminal of buffer 101. It is. The output terminal of the adder 9 is connected to the data input terminal of the read-only memory 100. It is connected. The data output terminal of the memory 100 is connected to the input terminal of the buffer 101. has been done.

An address controller 102 is provided to generate the necessary memory addresses. .

The output terminal of the adder 98 is also connected to an absolute value circuit 104, and this absolute value circuit It has an output terminal connected to an input terminal of addition and subtraction circuit 106. this circuit The output terminal of the register 106 is connected to the input terminal of the holding register 108. The output of 8 is connected to the second input of circuit 106. Output of register 108 The power end is also connected to the input end of the limiter/interpolator circuit 110, whose output end is It serves as the output terminal of the processor.

Referring now to FIG. 4, additional details of the processor's coefficient multiplier circuit 92 are shown. It is. The circuit 94 combined with the quadrature data Y, make a move.

Multiplier circuit 92 includes a four-power multiplexer circuit 116. multiplex The sensor 116 receives a 13-bit parallel digital signal applied to a selected one of the four input terminals. data may be transferred to the output to conductor 118. 10-bit Xn data on 4-wire 120 The data is fed directly to the input IN o of multiplexer 116 . Input terminal I The X data supplied to N+ is multiplied by 2 by multiplier circuit 122. times The line 122 is simply connected to one position in the x wire to IN +. The least significant bit of TN+ is shifted by one more significant bit than the least significant bit of x2. It consists of wiring to the upper bits (and so on). Connect to input terminal ■N2 >(x data has been multiplied by 4 by multiplier circuit 124. is simply wire 120 shifted two positions as it is routed to IN2. The multiplication function is realized by having 10 bits of the above X space data. lastly, The X data applied to the input terminal IN3 is multiplied by 6. Multiplication is on conductor 120 The data is multiplied by 2 through circuit 126 and by 4 through circuit 128, and This is achieved by adding the results of these multiplications using an adder 130. There is. Circuits 126 and 128 are similar to multiplier circuits 122 and 124, respectively. are doing.

Multiplier circuit 92 further connects output leads 132, 134 and 1 in a predetermined sequence. It includes a control logic circuit 131 that provides digital signals on 36. Conductor 132 The upper output is the 2-bit data fed to the selection input of multiplexer 116. It is. The two bits of data on conductor 132 are sent to all four inputs of the multiplexer. Controls which input is applied to that output. If the constant S or T is also +1 Or, if it should be -1, input terminal INO is selected, and +2 or -2 is selected. Input terminal IN+ is selected if it should be set, and input terminal IN+ is selected if it should be set to +4 or -4. If input terminal IN2 is selected and should be +6 or -6, input terminal IN3 is selected. selected.

The output 4-wire 134 of the controller 131 is connected to the zero input terminal of the multiplexer 116. There is. If a signal is applied to this input, all outputs of the multiplexer are It is zero. Therefore, if the constant S or T should be zero, the controller 131 A signal is provided on conductor 134.

The parallel outputs of the 16 bits 7) of multiplexer 116 are shown by conductors 118. A selectable switch is controlled by the output of controller 131 via conductor 136 so as to is supplied to a complementer circuit 138 which is capable of If the signal is on the conductor] 36 If not present, the complementer circuit 138 receives the data applied to its input. produces a digital output on conductor 140 identical to . The signal on conductor 136 The data output on line 140 is combined with the data from multiplexer 116. Make it a ment. Therefore, if the coefficient S or T should be negative, the controller 1 31 provides a signal on conductor 136.

The functions performed by complementer 138 are actually performed indirectly. too If both the X and Y data need to be combined, the data is first added by adder 96 (3171st) and then sent to adder 98. Sent. Adder 98 is then commanded to perform a subtraction function. If Y attack de If only data need to be combined, adder 96 performs a subtraction function. be instructed to do so. Finally, if only the XK data needs to be combined If so, both adders 96 and 98 are commanded to perform the subtraction function.

190 μs sump following the first of five ultrasound bursts along the beam direction During the beam line form ○ (n=0) occurring during the ring period, the adder 96 (the 3) generates a sequence of values as shown in Table 1.

Such The first four values in Table 1 are calculated from the demodulator output signals xg and Y8; is the first sample (k=o) of the +1 fJI instrument data for the beam line.

During the next time interval (k=],) which is the next 1.12 μs time interval, the demodulator output is sampled again to give the data pair X3 and Y. The following four outputs in Table 1 Force values are derived from this new data. This process begins with the first ultrasound burst. During each of the remaining intervals (k=2 to 174) following delivery! 1! Continue.

Each time adder 96 completes its operation and the sum is provided to a second adder 98 at the same time. , data is read from the random access memory 100 and stored in the buffer register. 101. The output terminal of the register 101 receives the data given by the adder 96. is connected to a second input of adder 98 for addition of . sum is next is loaded into the second buffer register 103 and then used in the previous read. It is returned to the memory 100 at the same address. Memory addressing is performed using address controller 102. Memory 100 is preferably a fast starter. It is made from tick random access memory. Hitachi type HM6116- An 8-bit 4x2 word CMOS memory with part number P2 is suitable for this purpose. It has been found that

During beam ray format 〇　(n=o), the data is read from the memory 100 and sent to the adder 98. The supplied data is all zero by activating the reset control to the buffer 101. be forced to. This does not occur with other beam line types (n-1 to n-4). beam The zero data in linear form 0 is then added to adder 9 to produce the values shown in Table 1. 8 is added to the data from adder 96. The sum is then recorded in memory 100. be remembered.

A separate area of memory 100 (5j, for each pair of instrument samples (X and Y) It is provided. Each area has four addresses. During the beam line form O, the th The four addresses for one demodulator pair (χ8 and Y8) are shown in Table 2. It holds four values.

X 3 S o + Y 8T.

XgTo YjjS.

During the remainder of beam line format O, the following 169 data samples (n-1 to 174) The four values associated with each are stored in additional memory locations.

During the next beamline (n=1), the values given by adder 96 are shown in Table 3. It is.

Such The values in Table 3 correspond to the in-memory herotation during the previous beam line format (n=o). are sequentially sent to an adder 98 to be added to the value. First beam line form O value are shown in Table 1. The added results shown in Table 4 are at the same position. is returned to memory.

Σ XgSo-Y:To+X', 5t-Y', T+X:To+Y:So+X? T++ Y? S+X: S o + Y g T o + X 7 S + + Y ? T+X: Ta lsa+X? T+-IS+ XaSo-Y;To+X;5t-YjT+XaTo+YMiSo+XjT++Y ’, S+X 4 S O+ Y 4 T O+ X; S + + Y: T + X 4 T o - Y, 'S o + X', T + Y; S+X5So-Y:To+X7S+Y? TIX g T O + Y g S O + X j T 1 + Y j S I etc. The same sequence is repeated for the subsequent three beam line formats (n=2-4) be done. During the last or fifth beam line type, (n=4), the memory 100 Updated with the values shown in the table.

+xys3-y treasure S3+X:S4 Y:T4X g T O+ Y 8 S O +X? TI+Y? S I + X”: T2 + Y: T2+XτT3+Y Treasure S l+X: T→+Y: S4X8SO+Y 8TO+X9. St+Y? T+ +X7S2+YjT2τχτS3+YτS 1 + X: S s + Y: T 4X: TOY8SO+X? T.I.Y. ? S+”X:T2 YffS2+X’7T3-Y copy S3+X, o T4- Y o, S 4X 2 S o Y Q T O+X: S + Y: T I T X i 37 Y i Ty + X i S 3 Y T 3 + X 4 S 4- Y 4 T 4χ4 To+Y5So+XjT+ +Y ;S+ +Xj-r’2+YiS2+XjT3+YjS3+ X: T 4 + Y 4 S 4X a S o + Y A T o +　X　j　S　+　+,　Y　j　T　+　　” T 2 + X f S 3 + Y! T 3 + X: S 4 TY 2 T 4X Q T o Y 4 S o + X +, T + Y’ , S + + X% T2-¥: S2+X1TI YiSt+X 4T4 Y4S4X5So Y:To+XjS+YjT++X;S2 Y3T 20X i S 1- Y i T 3 + X i S 4- Y mini 4X ’j, T o + Y Q S O + X’, T I + Y S + +χj T 2 + Y i S 2” X’r T 3” Y i S 3 + X 4 T 4 ↓ Y i S 4 etc. The first four values stored in memory 100 during the final beamformation are the fifth As shown in the table, the speed estimator ■0 is determined from equation (1). 6, which corresponds to the 4 terms used to calculate, are also stored in memory The following four terms are used to calculate the speed estimator ■1. at the time Each of the next four consecutive values stored in memory at to calculate the remaining speed estimators ■2 to ■174 in the same way. used for.

Referring now to Figure 5A, the time sequence for a portion of the sector scan is further illustrated. explain. Row A of the time diagram of FIG. 5A is approximately 1.5 m of the complete sector scan. / 2 shows the beam direction in which ultrasound waves are sent to generate blood flow data. ,6. All i-beam directions are used to generate blood flow data over the entire scan. It will be done. As shown, all 30 beam directions are used for half-scanning, Each direction is labeled with a direction number O through 29. Row B of the diagram is the elapsed time is expressed in μS. 1/2 scan requires approximately 30μs, and beam direction change is 1rn Occurs every S.

Rows B, C, D and E of Figure 5A are enlarged between scan direction line numbers 1 and 2. indicates the time interval. 5 occurring in each beam direction, as shown by row B. There are three beam line types (0-4). The duration of each beam line is approximately 200μs It is.

The time period of beam line type 3 with beam direction number l is shown in rows F and G. . This period falls between 1600ms and 1800ms of scanning. habo first 8 During μs, the probe 12 sends out ultrasound waves. During the remaining 192 μs, the probe acts as a receiver and detects the reflected ultrasound waves. Typical increase in reception interval The interval is shown in row H. This section is the 1616°00μs point of scanning. It yields between 1621.60 μs point.

Next, referring to FIG. 5B, read/write operations of the memory 100 of the processor unit 60 will be described. Further explains the process and related events. Beam direction number 1 beam line type 3 Using as an example the time interval shown in row H of FIG. 5B that occurs between do. Line A of FIG. 5B shows the time interval of the scan to be examined. Row B is 1616 The relative time is shown with zero at 00 μs. The period shown is 0.28 It is resolved into μs intervals. Multiply the same phase coefficient at the beginning of the first 0.28 μs interval Calculator 92 (FIG. 3) provides signal X1 as indicated by line C of FIG. 5B. It will be done. Similarly, the quadrature coefficient multiplier 94 outputs the signal as shown by the rows. Y1 is given. These values become Xl and Xl respectively after 1.12μs as mentioned above and Yl.

During the first part of the first 0.28 μs interval, the coefficient multiplier 92 applies 8 3, and the coefficient multiplier 94 multiplies the data Yl by T3. These values are As shown along the lines in Figure 5B, the addition that produces the output value X1S3Y')T3 The signal is supplied to a calculator 96. Multipliers 92 and 94 are also shown in row E. In other words, coefficient multiplication is performed once every 0.28 μs.

The write cycle and subsequent read cycle of memory 100 are 0.28μ Occurs once every s. For example, as shown in row F of Figure 5B, The contents of memory 100 at address 4 are the second half of the first 0.28 μs interval. is read between.

The data read from the memory 100 at address 4 at this time is shown in row G. It is also temporarily held in the buffer 101 (FIG. 3). Next 0. During the first half of the 28 μs interval, starting at relative time 0.28 μs, data is data is written into memory address 3. These data are in the following beam line formats or Not used or shown in . Also, at this point, exactly read from address 4. The extracted contents of buffer 101 (shown in line G) are output by adder 96. added to the input data. This addition performed by adder 98 is shown in row H. and the sum is temporarily held in buffer 103 (FIG. 3).

During the last half of the 0.28 μs interval, ending at the relative time 0.56 μS, The contents of memory 100 at address 5 are read and shown in lines F and G. The data is stored in the buffer 101 as shown in FIG. Additions stored in buffer 103 The output of calculator 98 is then at the relative time point 0.0, as shown in lines F and G. at address 4 during the first half of the next 0.28 μs interval starting at 56 μs. and written into the memory 100.

The above alternating read/write sequence consists of four digits of memory 100. Until the data of beam line format 3 for 2 = 1 is stored in addresses 4 to 7) Repeated. The sequence then continues with memory addresses 8-11 being beamline type 3. Starting at the relative time point 1.12 μs connected to be loaded with data of k =2. The memory loading sequence is beam line type 3. Repeat for the rest of the data. During the next final beam line (format 4), The data in memory 100 is duplicated with beam line format 4 data in the same manner as described above. will be combined. The combined data is then sequentially passed through the absolute value circuit 104 ( (Fig. 3), addition/subtraction circuit 106, register 108, and limiter/interpolator circuit + 10. These data circuits generate beam line type 4 data. Not active until then.

The various components, including processor unit 66, operate simultaneously and synchronously with each other. . Thus, for example, coefficient multipliers 92 and 94 operate on one group of data; Adder 98 and memory 100, on the other hand, operate on the other group of data. Also, k= Memory write for 1 = 2 = 4 memory write and similarly for k Memory reads for larger values are interleaved. “Pipe lining This operation, sometimes referred to as , allows for high-speed data processing.

As indicated by block 104, the final beam line form (n = 4) The absolute value A of the data stored in the memory 100 during this time is calculated sequentially. Sara Once the absolute value of the memory surface is determined, as indicated by block 106 in FIG. When the value A is set, the value A is first read from memory and temporarily stored in the holding register 108. is added to or subtracted from the value B held in . Values A and B are given by equation (1). The four absolute value terms are added to or subtracted from each other according to their previous sign. and For example, the velocity estimation for the first time interval (■0) along one of the 30 beam directions. The imager is as follows.

V'=l (X: So-YgTo (1) + X? S + Y? T + +X’jS2 YYTz + xys 3-yHT.

The function of absolute value circuit 104 is performed indirectly. If the output of buffer 103 is negative If so, the normal addition/subtraction operations of circuit 106 are reversed. if not negative , a regular addition/subtraction operation is performed.

Next, referring to FIG. 6, a song generally representing the transfer characteristics of processor unit 6 Line 112 is shown. The horizontal axis of the graph is the dots detected by reflected ultrasound. The vertical axis represents the Tsuppler shift, and the vertical axis is generated by Brose, 7 subunits 66. It represents the size of the composite speed estimator ■6. speed estimator v′ The magnitude and sign are represented by the color and intensity of the blood original image obtained on the display. ing. The Doppler shift, which is proportional to the component of blood velocity in the direction of the probe, is The ultrasound waves reflected from the blood volume are sampled at the frequency rS. Ru. As mentioned above, a typical ultrasound burst occurs once every 200ms. and a specific volume of blood is sampled at the same rate.

Therefore, the sampling rate fs is 5kHz.

Curve 112 is essentially a Doppler shift (blood velocity) with variables X and Yi. 1 is a plot of equation (1) as shown. For blood flow towards probe 12 The first two absolute value terms in equation (1) are dominant, and a positive value of ■1 occurs. be done. For high velocity blood flow, the velocity estimator should be large. The color modulator 76 (FIG. 2B) then produces a bright blue output. towards probe 12 For such slow blood flow, the brightness of the blood original image is reduced. probe 1 For the blood flow leaving from 2, the last two absolute values of equation (1) are dominant. , and a negative value of V' is generated. For high velocity blood flow towards the probe In this case, color modulator 76 produces a bright red image. The magnitude of the velocity decreases in the same direction. If so, the image will be dark.

An important feature of the invention is that the diagnostic device according to the invention uses relatively low frequency Doppler It has the ability to eliminate signals. It causes body organs like the heart to move at lower speeds. These signals, which are largely generated by reflections from the walls, interfere with the display of blood source information. do. As can be seen from FIG. 6, the curve 112 is located near the origin at the first and It becomes highly nonlinear within the third quadrant. This curvature is the organ that the device according to the invention moves. significantly increases the ability to reject low frequency Doppler signals generated by . Preferably, when the magnitude of ■ decreases below a predetermined value into the dead zone 114, the A circuit that generates a thinking force is provided on the display. The bend of the curve 112 is This can be achieved by selecting appropriate values S1 and Tn in equation (1), as explained below. It will be done.

(Sampling Ray for high-speed blood flow) Doppler software comparable in size to f+ can occur. For example, as shown in Figure 6, 0.33fs A Doppler shift that is too large will result in a reduction in image brightness, contrary to the desired result. Ru. If the Doppler frequency is greater than 0.5fS, is the image actually blue? to red. This phenomenon is generally called aliasing. Dotsupu The error shift may be, for example, 3 kHz, in which case the 5 kHz Aliasing will occur if typical sampling frequencies are used.

Therefore, the sampling frequency must be increased. But if the sump If the ring frequency is made too high, the internal energy generated from one burst Ultrasound reflected from a deep part of the body and a shallow part of the body generated from the next birth 1- There is a possibility that it may be confused with reflected ultrasound waves. This ambiguity is due to the fact that reflected ultrasound This can be avoided by limiting processing to a predetermined maximum depth. This maximum depth is It is related to the pulling frequency and the speed of sound within the body. For example, if aliasing If it is necessary to increase the sampling frequency to 1QkHz to avoid The speed of ultrasonic waves in tissues is approximately 6.5 cm/μS, so can be avoided by limiting the depth at which processing is done to about 6 cm.

As mentioned above, curve 112 in FIG. 6 is essentially a plot of equation (1). this The particular formula, including the values of the coefficients Sn and Tn, may be preferred for the application of the present invention. Although found, other transfer functions may also be used. In this regard, strict mathematical Equation (1) is further explained using an intuitive rather than analytical approach.

The Doppler signal provided to the processor unit 66 can be expressed by the following equation.

vinegar). X is the in-phase component of the signal, Y is the quadrature component of the signal, and k is the time and n is the beam line format number. In the preferred embodiment, k is 0 to 174, and n varies from 0 to 4. The term W is on the complex plane It can be visualized as five facers plotted. These facers are 5 X and Y generated by the detector from the reflected ultrasound for the beam line format of x, determined by Inheritance (facer detected Doppler of reflected ultrasound) Occurs at positions around the origin at a rate matching the shift. The direction of rotation is clockwise direction for blood flow towards the probe 12 and away from the probe. The direction is counterclockwise for blood flow. In the time domain, the values X and Y are A sinusoidal waveform with phases 90 degrees out of phase with each other and a frequency equal to the Doppler frequency represents. For the flow away from the probe, the X waveform lags behind Y and x. In addition, the flow toward the probe is ahead of Ys.

The value An' is a set of five complex numbers, and kn is shown to be the complex conjugate number of . It is selected so that the magnitude of Rゞ is large. ing. As mentioned above, various values of W i for blood flow in this direction are successively larger. can be represented by a facer with a large phasor angle. Therefore, the facer is clockwise 6 is selected to be small. If the Doppler frequency is low , the sequential phase shift of the five facers is relatively small. In the time domain, 5 The Doppler signal waveform over the time period over which two samples are made is approximately constant. It appears as a straight ramp with an offset and a slight curvature. Therefore, One constant and a term proportional to (n-2) (this term is 5< ) and a term proportional to the square of (n-2>).

'JJ; = 2 + b (n-2) +: (n-2)' (4) term of formula (1) Sn and Tn represent the real part and imaginary part of hn as shown in the following formula.

Rn=Sn + j Ding-n (5) The five values of each of Sn and Tn in equation (1) are the constants shown in equation (4), ( so as to be insensitive to terms proportional to n-2> and to terms proportional to the square of (n-2). was selected by the sea urchin. Sn was chosen to be an even function of (n-2). The following formula The relationship was the basis for selecting the five values of sn.

4SO+SI+S3+4S4=O(7) Equation (6) is insensitive to the constant term of Equation (4) guarantee sex. Furthermore, equation (7) guarantees the insensitivity of the square proportional term 1 in equation (4). Ru. Additionally, Sn was chosen to be a symmetric function of (n-2). Amplitude of S2 was arbitrarily set to 6. S3 and S4 are according to equations (6) and (7), They were selected as -4 and 1, respectively.

Since sn is an even function, 5O=34=1 and 51=32=4.

The value of Tn was chosen as an odd function of (n-2). This TnO value is determined by the equation (4). guarantees insensitivity to numbers and squared proportional terms.

The coefficient T3 was arbitrarily set to -4. Guaranteed insensitivity to the negative power proportional term in equation (4) Therefore, the following formula was used.

2To−T+ +T1 2T4=O(8) From equation (8) and other constraints, T4 was chosen as 2, T+=-T+=4 and To=2. Insensitivity to low-speed motion Other values of 5t-t and Tn may also be selected to obtain susceptibility or approximate insusceptibility. It will be understood that

The above values of Sn and Tn are approximately evenly distributed around the origin of the complex plane5. yields two complex coefficients hn. The coefficients are distributed around the origin in a clockwise direction. are sequentially generated by the bits 66.

As mentioned above, the five values of gold are sequentially arranged at a rate equal to the sampling frequency rs. It can be seen as five facers on the complex plane that are then generated. If the blood flow is If leaving the lobe 2, the facer will be generated in a clockwise direction. on the other hand , if the blood flow is towards the probe 12, the facer will move in a counterclockwise direction. occurs in

As can be seen from equation (3), the value G' is obtained by multiplying the phasor base by the coefficient hn''. is generated by adding together the five complex values obtained. If blood flow has left the probe 12, the phase angle of the coefficients vJ, Rn" and the value Ws is proceed in the same direction. In that case, the five bonds have approximately the same phase angle and therefore also add Actively participate in calculations. If the blood flow is in the opposite direction, the coefficient has an angle . Therefore, when the products are added, the magnitude of the final value is small. Therefore, the term ck is Relatively large relative to the blood flow leaving the probe, and relative to the blood flow toward the probe. For low frequencies generated by organ walls and blood that also move at low speeds It is relatively small compared to the Doppler. The additional term H' can be expressed as:

With the exception of the term (9), the value Rn is used instead of the conjugate value Rnh. , is similar to the term in equation (3). Therefore, if blood flow leaves probe 12, If It is aggressively large and relatively small relative to the blood flow toward the probe. , and is relatively small compared to the moving septic wall.

The speed estimator V' can be determined from the values G' and H6 according to the formula below.

V'=+1ReH' l+l ImH' l Also, the first two terms of equation (1) are I guess. The last two terms of equation (10) approximately represent the magnitude of a′, and the equation ( This corresponds to the last two terms of 1). As mentioned above, the first two positive terms represent blood flow. is dominant when leaving probe 12, and the last two negative terms are negative when leaving probe 12. Dominant when liquid flow is towards the probe. This corresponds to curve 112 in Figure 6. More shown. All four terms are represented by dead zone 114 of curve 112. As shown, it is not sensitive to low-frequency Doppler.

Additionally, as mentioned above, the ultrasonic device according to the present invention is designed to ensure optimum operation. It is necessary to adjust the pulling frequency rs. The sampling frequency is the well-known Nike should be at least twice the frequency of the maximum Doppler shift according to the strike norm. be. As can be seen from curve 112, if the sampling frequency fs is the maximum dop Below twice the error shift, undesirable aliasing will occur. too However, if the sampling frequency fs is too high, the Doppler signal becomes a signal with a low frequency e. appears. As mentioned above, equation (10) is optimized so as not to respond to such signals. has been made into The most common sampling frequency, f, allows optimal blood flow images to be generated. This can be determined by monitoring the display up to.

Five samples of ultrasound waves reflected from specific points (n-0 to 5) of the blood flow are optimal Other values may also be used, although they have been found to yield good results. For example, generate speed estimator ■3 from only four samples (n = 0 to 3). It has been confirmed through experiments that an appropriate blood flow image can be obtained by this method. but , the resulting response curve shows that the refraction at the origin is clearly shown in Figure 6. It is inferior to the curve in Figure 6 in that there is no curve. Therefore, the system using four samples The system is susceptible to interference from slow-moving organ walls. Speed estimator output Adequate results were obtained by using only three samples (n-0 to 2) for raw data. It is not believed that it will happen.

It should also be noted that the number of samples may exceed the optimal number 5 mentioned above. . In fact, the sensitivity of curve 112 in FIG. This can be slightly improved. However, given the sequence of velocity es along a given beam direction, The time required to generate the timer increases as the number of samples increases. increases to Therefore, the number of beam directions that can be displayed without substantial image flicker is 1 It will decrease. Speed estimation meter ■6 is generated and one is the sampling frequency can be increased by increasing r. However, as mentioned above, in 14Jl ffl The speed of the ultrasound imposes a limit on the maximum sampling rate. Therefore, if the sample The depth at which blood velocity data is processed should the rate of conversion be increased significantly. restrictions must be imposed on Otherwise, one ultrasound burst will The ultrasonic waves are reflected from deep within the body and the subsequent bursts of ultrasonic waves are generated. An ambiguity arises between ultrasonic waves reflected from shallow parts of the body and generated by ultrasonic waves.

From the above constraints, the sample used to generate the speed estimator The benefits of the present invention can be achieved by increasing the number of files to a value greater than 8 (n=o~7). is not believed to be obtained. The optimal value is 5 samples as described above. sa The preferred range for samples is 4 to 6, with samples less than 4 or more than 8 The full benefits of the invention are not obtained.

Referring again to Figure 3, the speed estinotor V0 is reset from the holding register 10th. mitter/interpolator circuit] 10. Limiter/interpolator circuits are large Controls the brightness of the image generated from the velocity estimator V', thereby reducing the Prevent play damage. The limiter function uses a 16-bit speed estimate meter data. 5 bits for storage in the scan converter memory 70 (FIG. 2B). A pair of programmable read-only memories (FROM) (Fig. (not shown). The lowest 4 bits are due to digitization error. It is omitted because it is overshadowed. The next five least significant bits indicate that the output data is It is used as output data unless there is a barflow. If positive overflow If present, the maximum allowable value, 01111, is output from memory. too If negative overflow exists, the maximum allowable negative value of 10000 is used. It will be done. Table 6 shows the various outputs produced by the limiter function of circuit 110.

Jade craft 1 Speed estimation meter Displayed color Speed V 01111 Bright blue High speed towards the probe 00001 Dull blue towards the probe Slow speed towards oooooo Chess No speed 11111 Dull red probe leaving slow speed 10000 Bright red probe? The interpolator function of the high speed circuit 110 departing from the Ru. The appearance of large square pixels on the display occurs in successive samples (1, 12 By filling the area between This has been avoided. This internal press uses a digital adder and is divided by 2. By wiring the outputs shifted l bits to obtain the sum (i.e. the average value). It is done in a standard manner.

The conditioned speed estimator ■6 is, as mentioned above, As the stay meter is generated through a sector scan, the scan converter memory 7 0 (Figure 2B). The corresponding anatomical echo data is also converted. loaded into data memory. Once all the data corresponding to a complete sector scan Once loaded, memory 70 stores a standard rask scan format for the display. Read out in matte. Typically, 30 fan scans are generated every second, which is It is fast enough to generate moving images of liquid flow and 811 chemical structures.

As mentioned above, we have developed a new ultrasonic diagnostic device. Regarding preferred embodiments of the device Although it has been described in detail, it is within the scope of the present invention as described in the claims. It will be apparent to those skilled in the art that various modifications are possible.

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Claims (1)

[Claims] 1. for transmitting a series of ultrasound bursts towards the blood whose flow is to be measured. Ultrasonic transmitting means; an ultrasound receiving means for receiving ultrasound reflected from the blood; the difference between the frequency of said transmitted ultrasound and the frequency of said received ultrasound; detection means for detecting and generating corresponding frequency difference data; In response to the frequency difference data mentioned above, each of N (N varies from 4 to 8) speed esthetics using the frequency difference data obtained from the ultrasonic burst of Velocity estimator data that generates velocity estimator signals that indicate blood flow velocity. processor means for generating data; a device for displaying an image of said blood flow in response to said velocity estimator data; display means and An ultrasonic diagnostic device for measuring blood flow in the body, comprising: .