JP2007301180A - Ultrasonic diagnostic apparatus and method of generating ultrasonic diagnostic image - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ultrasonic diagnostic apparatus obtaining a diagnostic image matching the tissue structure of a subject. <P>SOLUTION: The ultrasonic diagnostic apparatus has an ultrasonic probe 2. The ultrasonic probe 2 repeatedly transmits ultrasonic pulses to a subject based on the time interval of transmission corresponding to the pulse repeating frequency, and receives echo signals from the subject based on the time interval of receiving corresponding to the sample volume. The ultrasonic probe does not receive echo signals from the subject during a prescribed prohibition period while a prohibition period setting changing part changes the setting based on the value of the prohibition period inputted in a prohibition period input part, including the time when ultrasonic pulses are transmitted to the subject. The prohibition period is different in length between the normal state of PRF (Pulse Repetition Frequency) in which the time interval of transmission is longer than the time interval of receiving and the state of HPRF (High Pulse Repetition Frequency) in which the time interval of transmission is shorter than the time interval of receiving. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an ultrasonic diagnostic apparatus and an ultrasonic diagnostic image generation method using a pulse Doppler method.

  In a medical diagnosis, there is a pulse Doppler method as a method for repeatedly transmitting ultrasonic pulses to a subject and measuring a blood flow velocity or the like. The pulse Doppler method generates an ultrasonic diagnostic image that obtains a spectrum display of the movement state of a subject by obtaining a change in frequency of the transmitted ultrasonic pulse repetition frequency (PRF) and reflected ultrasonic pulse. Is the method.

A typical ultrasonic diagnostic apparatus using the pulse Doppler method is disclosed in Patent Document 1.
First, consider using the ultrasonic diagnostic apparatus disclosed in Patent Document 1 to display a B-mode diagnostic image of a subject as a reference image on a display unit. For example, when a blood vessel is running in the subject, the blood vessel is displayed on the display unit. Next, the operator inputs the position of the sample volume while viewing the B-mode diagnostic image.

  When the B-mode diagnostic image displayed on the display unit is switched so that the D-mode diagnostic image is displayed, the movement state of the subject at the position of the sample volume can be measured.

  When displaying a D-mode diagnostic image on the display unit, a time for transmitting an ultrasonic pulse from the ultrasonic probe of the ultrasonic diagnostic apparatus to the subject and receiving an echo signal reflected by the subject with the ultrasonic probe The chart is shown in FIG. In FIG. 4, the ultrasonic pulse Ps transmitted from the ultrasonic probe to the subject consists of a pulse having a repetition frequency, and the pulse transmission time interval is a reciprocal of the pulse repetition frequency, PRT (in this case, the transmission time interval). Defined).

  The pulse repetition frequency is a value of a pulse repetition frequency set by an operator who operates the ultrasonic diagnostic apparatus. That is, when it is desired to increase the diagnostic resolution of the subject, the pulse repetition frequency is increased, and when the deep location of the subject is diagnosed, the pulse repetition frequency is decreased. In particular, when the pulse repetition frequency is increased, the frequency of the ultrasonic pulse transmitted from the ultrasonic probe is increased, so that it is possible to measure the faster movement of the diagnostic part of the subject.

  The ultrasonic pulse Ps transmitted from the ultrasonic probe toward the subject is reflected, for example, at the position of the sample volume of the subject, and the ultrasonic pulse returns to the ultrasonic probe again as an echo signal Pr. Received by ultrasonic probe.

  The echo signal Pr reflected from the sample volume is 2 L / v after transmitting the ultrasonic pulse from the ultrasonic probe, where L is the distance from the position of the sample volume and the ultrasonic probe, and v is the sound velocity. After elapses, the echo signal Pr is received by the ultrasonic probe. This time is the reception time interval from when the ultrasonic probe transmits an ultrasonic pulse to the sample volume of the subject whose distance from the ultrasonic probe is L until the echo signal Pr reflected from the subject is received. As shown in FIG. 4, Tdepth is obtained.

Japanese Patent No. 3610347 JP 2004-195018 A

  During the D-mode diagnosis according to the time chart of FIG. 4, it is assumed that the transmission time interval of ultrasonic pulses is kept constant, that is, the PRT is kept constant and the position of the sample volume is deepened. As a result, the reception time interval Tdepth becomes longer. As Tdepth becomes longer, as shown in FIG. 5, the transmission time interval of the ultrasonic pulse becomes shorter than the reception time interval at a certain time, and PRT <Tdepth. Similarly, when the depth of the position of the sample volume is kept constant and the pulse repetition frequency to be transmitted is increased, the transmission time interval of the ultrasonic pulses becomes shorter than the reception time interval, and PRT <Tdepth Become. This state is said to have changed from the normal PRF state to the HPRF (High Pulse Repetition Frequency) state.

  In the ultrasonic diagnosis by the pulse Doppler method, when the state is changed from the normal PRF to the HPRF state, the quality of the Doppler waveform is deteriorated, and the display image quality on the display unit of the ultrasonic diagnostic apparatus is rapidly deteriorated. In the HPRF state, when the previously transmitted pulse is reflected from the subject as received from the position of the sample volume and received (Pr of main in FIG. 5), the pulse transmitted later is from the position of the sample volume. Since it is reflected from the subject as being from the position of the shallow subsample volume, it is also received (Pr of sub in FIG. 5). In other words, as shown in FIG. 5, when the HPRF state is entered, the ultrasonic probe receives two signals: a main echo signal Pr from the sample volume and a sub echo signal Pr from the subsample volume. . Then, since the Doppler waveform is calculated from these two received signals, the accuracy of waveform formation is lowered, and the display image quality on the display unit is deteriorated.

  In particular, when the tissue corresponding to the position of the sample volume is blood, and the tissue corresponding to the position of the subsample volume is skin, muscle, etc., the echo signal from the position of the sample volume is Since the signal is weaker than the received signal from the position of the volume, it is difficult to separate the echo signals. When the tissue at the position of the subsample volume is a myocardium or the like, the intensity of the received signal of the subsample volume becomes stronger due to the intense movement of the myocardium. For this reason, the echo signal from the position of the sample volume is buried in the received signal from the position of the subsample volume.

  Therefore, as shown in FIG. 6A, in the time zone C, a predetermined time zone C including the time zone A in which the ultrasonic pulse Ps is transmitted from the ultrasonic probe toward the subject is set as a prohibited time. The echo signal Pr from the subject is not received. A time zone C shown in FIG. 6A is composed of a time zone A in which the ultrasonic pulse Ps is transmitted and a predetermined time zone B after the ultrasonic pulse Ps is transmitted. Here, the ultrasonic probe 2 is composed of ultrasonic transducers arranged in an array, and cannot transmit and receive ultrasonic pulses simultaneously. Therefore, first, the time zone A during which the ultrasonic pulse Ps is transmitted is set as the prohibited time. In order to prevent the quality of the Doppler waveform from deteriorating when transitioning from the normal PRF to the HPRF state, a predetermined time zone B after the elapse of the time zone A is also set as a prohibited time.

Due to the existence of the prohibition time consisting of the time zone C, the reception time zone of the echo signal Pr does not overlap with the time zone C. This is the same when the value of the pulse repetition frequency is changed and when the position of the sample volume is changed.
For example, consider a case where the operator of the ultrasonic diagnostic apparatus performs an input operation of a pulse repetition frequency that shortens PRT (a) in the normal PRF state as shown in FIG. However, when a pulse repetition frequency is input such that the PRT is shortened, the time zone C for the PRT corresponding to the input pulse repetition frequency may overlap the reception time zone of the echo signal Pr. In such a case, as shown in FIG. 6 (b), the end R of the time zone C corresponds to the input pulse repetition frequency so that it comes before the start Q of the reception time zone of the echo signal Pr. The PRT is forcibly shortened to become PRT (b). In addition, the transmission / reception unit 14 performs control to transmit the ultrasonic pulse Ps based on the PRT (b) forcibly shortened by the ultrasonic probe 2. The state shown in FIG. 6B is a state of HPRF where PRT (b) <Tdepth (a).

  On the other hand, let us consider a case where the operator of the ultrasonic diagnostic apparatus performs an input operation of the position of the sample volume so that Tdepth (a) becomes long in the normal PRF state as shown in FIG. However, when the input of the position of the sample volume such that Tdepth is increased, the reception time zone of the echo signal Pr at Tdepth corresponding to the input sample volume may overlap with the time zone C. In such a case, as shown in FIG. 6C, the T depth is forced to T depth (c) so that the end R of the time zone C comes before the start Q of the reception time zone of the echo signal Pr. Make it longer. The state of FIG. 6C is an HPRF state where PRT (a) <Tdepth (c), but the time difference between PRT (a) and Tdepth (c) is longer than the time zone C. Therefore, it is possible to prevent the display image quality of the display unit from deteriorating.

  In the conventional ultrasonic diagnostic apparatus, in order to avoid deterioration of display image quality in the display unit when the normal PRF state is changed to the HPRF state during diagnosis, the prohibition time of the time zone C shown in FIG. Among them, the time zone B is taken as long as possible. In particular, in order to avoid deterioration in display image quality when the echo signal from the position of the sub-sample volume is strong, it is necessary to lengthen the time zone B shown in FIG. However, the time zone B is preset when the ultrasonic diagnostic apparatus is designed assuming that the echo signal from the position of the sub-sample volume is strong, and the time zone B cannot be changed during the diagnosis.

  In particular, when transitioning from the normal PRF to the HPRF state as shown in FIGS. 6B and 6C, the time zone B cannot be changed, so that the optimum HPRF display image quality may not be obtained. . That is, even if an operator of the ultrasonic diagnostic apparatus performs an input operation of the pulse repetition frequency or the position of the sample volume so as to be able to cope with the structural tissue of the subject, as described above, the PRT or Tdepth that is unintentionally forced It is because it will be changed to. Furthermore, if the time zone B of the prohibition time set at the time of design is too long, even if the signal intensity from the position of the subsample volume is weaker than expected, the pulse repetition frequency and sample volume intended by the operator In some cases, the position input operation could not be performed.

  Accordingly, an object of the present invention is to make it possible to obtain a diagnostic image that matches the tissue structure of a subject in an ultrasonic diagnostic apparatus and an ultrasonic diagnostic image generation method.

  The ultrasonic diagnostic apparatus according to the present invention repeatedly transmits an ultrasonic pulse to a subject based on a transmission time interval corresponding to a pulse repetition frequency, and receives a reception time interval corresponding to a sample volume at a predetermined position of the subject. An ultrasonic diagnostic apparatus having an ultrasonic probe for receiving an echo signal from the subject based on the ultrasonic probe, wherein the ultrasonic probe includes a time during which an ultrasonic pulse is transmitted to the subject, and a prohibited time input The ultrasonic probe does not receive an echo signal from the subject during the predetermined prohibition time set by the prohibition time setting change unit based on the prohibition time value input to the unit, and the transmission time interval However, the length of the prohibition time is different between the normal PRF state in which the transmission time interval is longer than the reception time interval and the HPRF state in which the transmission time interval is shorter than the reception time interval.

  In the ultrasonic diagnostic image generation method according to the present invention, an ultrasonic probe repeatedly transmits an ultrasonic pulse to a subject based on a transmission time interval corresponding to a pulse repetition frequency, and a sample volume at a predetermined position of the subject. An ultrasonic diagnostic image generation method for receiving an echo signal from the subject based on a reception time interval corresponding to the frequency and generating a diagnostic image of the subject based on the echo signal received by the ultrasonic probe. The ultrasonic probe does not receive an echo signal from the subject during a predetermined prohibition time including a time during which an ultrasonic pulse is transmitted to the subject. The normal PRF state in which the transmission time interval is longer than the reception time interval and the HPRF state in which the transmission time interval is shorter than the reception time interval The length of the stop time is different.

  In the ultrasonic diagnostic apparatus and the ultrasonic diagnostic image generation method according to the present invention, the length of the prohibition time during which the ultrasonic probe does not receive the echo signal from the subject depends on the normal PRF state and the HPRF state. Different. Therefore, it is possible to obtain a diagnostic image that matches the tissue structure of the subject.

  FIG. 1 shows a configuration according to the implementation of the ultrasonic diagnostic apparatus 1 of the present invention. An ultrasonic diagnostic apparatus 1 illustrated in FIG. 1 includes an ultrasonic probe 2, a B mode signal generation unit 3, a D mode signal generation unit 4, a control unit 5, an input device 6, a DSC (Digital Scan Converter) 7, and a transmission / reception unit 14. And have. The control unit 5 includes a pulse repetition frequency (PRF) setting unit 8, a sample volume position setting unit 9, and a prohibited time setting changing unit 10 described below. The input device 6 includes a pulse repetition frequency (PRF) input unit 11, a sample volume position input unit 12, and a prohibited time input unit 16 described below. A display unit 13 is connected to the DSC 7.

  The ultrasonic probe 2 is composed of ultrasonic transducers arranged in an array. The ultrasonic probe 2 transmits an ultrasonic pulse toward the subject 15 and receives an echo signal transmitted to the subject 15 and reflected. . The transmission of the ultrasonic pulse and the reception of the echo signal are performed via the transmission / reception unit 14 connected to the ultrasonic probe 2. The B mode signal generation unit 3 generates B mode data based on the echo signal received from the transmission / reception unit 14. Then, the D-mode signal generation unit 4 obtains a change in the frequency of the reflected ultrasonic pulse based on the echo signal received by the ultrasonic probe 2 and the ultrasonic pulse signal transmitted toward the subject, and the Doppler Generate a signal.

  In the ultrasonic diagnostic apparatus 1 shown in FIG. 1, there is a control unit 5 that controls transmission / reception of ultrasonic pulses of the ultrasonic probe 2 based on an instruction from an input device 6 operated by an operator. The control unit 5 includes the following pulse repetition frequency setting unit 8, sample volume position setting unit 9, and prohibited time setting changing unit 10.

  The input device 6 includes a pulse repetition frequency input unit 11 and a sample volume position input unit 12, and an input operation necessary for controlling the ultrasonic diagnostic apparatus 1 is performed by an operator. The DSC 7 generates an ultrasonic diagnostic image of a B-mode image based on the B-mode data generated by the B-mode signal generation unit 3 or a D-mode based on the Doppler signal generated by the D-mode signal generation unit 4 Ultrasonic diagnostic images of the images are generated, and these generated images are displayed on the display unit 13.

  The pulse repetition frequency setting unit 8 sets the pulse repetition frequency of the ultrasonic pulse transmitted to the subject 15. Then, the information is transmitted to the transmission / reception unit 14 so that the ultrasonic probe 2 can transmit the ultrasonic pulse to the subject 15 at the pulse repetition frequency set by the pulse repetition frequency setting unit 8.

  The sample volume position setting unit 9 sets a reception time interval until the echo signal reflected from the subject 15 is received after the ultrasonic probe 2 transmits the ultrasonic pulse to the subject 15. Information on the set reception time interval is transmitted to the transmission / reception unit 14, and the ultrasonic probe 2 receives an echo signal according to the reception time interval. This reception time interval is determined corresponding to the position of the sample volume P to be diagnosed of the subject 15 as follows.

  The pulse repetition frequency input unit 11 is connected to the pulse repetition frequency setting unit 8, and when the pulse repetition frequency of the ultrasonic pulse transmitted to the subject 15 is set in the pulse repetition frequency setting unit 8, the set value is set by an operator. You can enter. The pulse repetition frequency setting unit 8 sets the pulse repetition frequency so as to correspond to the set value of the pulse repetition frequency input by the pulse repetition frequency input unit 11.

  The sample volume position input unit 12 is connected to the sample volume position setting unit 9 so that the operator can input the position of the sample volume for obtaining the Doppler signal in the subject 15. Then, the sample volume position setting unit 9 sets a reception time interval corresponding to the position of the sample volume input by the sample volume position input unit 12.

  The display unit 13 is connected to the DSC 7 and displays a diagnostic processing image based on the B-mode data received from the B-mode signal generation unit 3 and the Doppler signal received from the D-mode signal generation unit 4.

  Based on the information on the pulse repetition frequency received from the pulse repetition frequency setting unit 8, the transmission / reception unit 14 controls the ultrasonic probe 2 to transmit an ultrasonic pulse to the subject at a transmission time interval corresponding to the set PRT. . Further, the transmission / reception unit 14 controls the ultrasonic probe 2 to receive an echo signal from the subject 15 based on the reception time interval received from the sample volume position setting unit 9.

  The ultrasonic diagnostic apparatus 1 shown in FIG. 1 further includes a prohibited time setting change unit 10 connected to the transmission / reception unit 14 and a prohibited time input unit 16 connected to the prohibited time setting change unit 10. The prohibition time setting change unit 10 changes the setting of the length of the prohibition time during which the ultrasound probe 2 prohibits reception of the echo signal Pr from the subject 15 when displaying the D-mode image on the display unit 13. The transmitter / receiver 14 connected to the prohibited time setting changing unit 10 receives the echo signal from the subject 15 during the prohibited time based on the information on the prohibited time from the prohibited time setting changing unit 10. Absent. The prohibition time input unit 16 can input the value of the prohibition time by the operator of the ultrasonic diagnostic apparatus 1. The prohibition time setting change unit 10 connected to the prohibition time input unit 16 sets and changes the length of the prohibition time based on the value of the prohibition time input by the prohibition time input unit 16.

  Consider using the ultrasonic diagnostic apparatus 1 configured as shown in FIG. 1 to display a B-mode ultrasonic diagnostic image of the subject 15 as a reference image on the display unit 13. For example, when a blood vessel is running in the subject 15 in FIG. V is projected. Here, the operator inputs the position of the sample volume SV using the sample volume position input unit 12 while viewing the B-mode diagnostic image.

  The B-mode image shown in FIG. 2 shows a sound ray SL in a predetermined direction of an ultrasonic pulse irradiated from the ultrasonic probe. The position of the pointer P corresponding to a predetermined depth L from the ultrasonic probe 2 shown in FIG. 1 on the sound ray SL is SV.

  When the B-mode diagnostic image displayed on the display unit 13 is switched so that the D-mode diagnostic image is displayed, the movement state of the subject at the SV position can be measured. As shown in FIG. 2, the SV has a predetermined width so that, for example, the blood flow velocity in a thick blood vessel (B.V) can be measured.

  FIG. 3 shows a time chart for transmitting an ultrasonic pulse from the ultrasonic probe 2 toward the subject 15 and receiving an echo signal reflected by the subject 15 when displaying a D-mode diagnostic image on the display unit 13. Indicated.

  As shown in FIG. 3A, the ultrasonic pulse Ps is directed from the ultrasonic probe toward the subject 15 at the transmission time interval PRT based on the value of the pulse repetition frequency set by the pulse repetition frequency setting unit 8. Have been sent. Then, the ultrasonic pulse Ps transmitted from the ultrasonic probe 2 toward the subject 15 is reflected at a point P which is the position of the sample volume of the subject 15, and the ultrasonic pulse becomes an echo signal Pr again. It returns to the direction of the ultrasonic probe 2 and is received by the ultrasonic probe 2.

  The time for receiving the echo signal Pr by the ultrasonic probe 2 is as shown in FIG. 3A. The ultrasonic probe 2 transmits an ultrasonic pulse to the subject 15 whose distance from the ultrasonic probe 2 is L. This is based on Tdepth, which is a reception time interval until the echo signal Pr reflected from the subject 15 is received after being transmitted to the point P as the sample volume.

  In FIG. 3A, the transmission time interval PRT of the ultrasonic pulse Ps transmitted from the ultrasonic probe 2 is in a normal PRF state where PRT> Tdepth in relation to the reception time interval Tdepth of the echo signal Pr. is there. However, conditions such as the transmission time interval PRT and the reception time interval Tdepth are changed by the operator operating the pulse repetition frequency input unit 11 and the sample volume input unit 12 during diagnosis even in a normal PRF state. In such a case, the HPRF state as shown in FIG. 3B in which PRT <Tdepth is satisfied, and the display image quality on the display unit 13 may be deteriorated. Therefore, as shown in FIG. 3A, the predetermined time zone C including the time zone A in which the ultrasonic pulse Ps is transmitted from the ultrasonic probe 2 toward the subject 15 is set as the prohibited time. In C, the echo signal Pr from the subject is not received.

  In the embodiment of the ultrasonic diagnostic apparatus of the present invention, in the HPRF state as shown in FIG. 3B, the ultrasonic probe 2 is in the time zone C ′ that is a prohibited time during which the echo signal Pr from the subject is not received. The length is made different from the time zone C in the normal PRF state as shown in FIG.

  Even in the HPRF state as shown in FIG. 3B, when the operator operates the pulse repetition frequency input unit 11 or the sample volume input unit 12, the transmission time interval PRT, the reception time interval Tdepth, etc. When the condition is changed and the normal PRF state where PRT> Tdepth is again obtained as shown in FIG. 3C, the length of the prohibited time is changed from the time zone C ′ to the time zone C. To do. The time zone C or C ′ is composed of a time zone A in which the ultrasonic pulse Ps is transmitted and a predetermined time zone B (or B ′) after the ultrasonic pulse Ps is transmitted. Here, since the time zone A during which the ultrasonic pulse Ps is transmitted cannot be substantially changed, the time zone B or B ′ is changed when the time zone C or C ′ is changed.

  It is desirable that the length of the prohibition time period C ′ in the HPRF state is shorter than the length of the prohibition time period C in the normal PRF state. Since the time zone C of the prohibition time in the normal PRF state becomes long, conditions such as the transmission time interval PRT and the reception time interval Tdepth are changed during diagnosis in the normal PRF state, so that the HPRF state is changed. The quality of the Doppler waveform at the time of transition is unlikely to deteriorate.

  On the other hand, since the time zone C ′ of the prohibition time in the HPRF state is shortened, conditions such as the transmission time interval PRT and the reception time interval Tdepth can be finely set in the HPRF state. Therefore, it is possible to set conditions that match the tissue structure of the subject.

  The setting change of the length of the prohibition time period C described above is performed by the prohibition time setting change unit 10 of the ultrasonic diagnostic apparatus 1 shown in FIG. In the ultrasonic diagnostic apparatus 1 shown in FIG. 1, the prohibition time setting change unit 10 can receive information from the pulse repetition frequency setting unit 8 and the sample volume position setting unit 9. That is, the prohibition time setting change unit 10 refers to the PRT information received from the pulse repetition frequency setting unit 8 and the TD depth information received from the sample volume position setting unit 9.

  If the prohibition time setting change unit 10 determines that PRT> Tdepth, the prohibition time setting change unit 10 sets the prohibition time period as shown in FIG. , Time zone C is set. When the prohibition time changing unit 10 determines that PRT <Tdepth, the HPRF state is set. Therefore, the prohibition time setting changing unit 10 sets the prohibition time period as shown in FIG. Set to C '.

  The setting of the time zones C and C ′ by the prohibited time setting changing unit 10 can also be realized by executing a program prepared in advance on a computer such as a personal computer or a workstation.

  The prohibited time setting change unit 10 sends information on the time zone C or C ′ of the prohibited time to the transmission / reception unit 4. The transmission / reception unit 4 controls so that the ultrasonic probe 2 does not receive the echo signal Pr from the subject 15 during the prohibited time of the time zone C or C ′.

  The prohibition time setting change unit 10 is connected to a prohibition time input unit 16 so that the operator of the ultrasonic diagnostic apparatus 1 can input the value of the prohibition time. Therefore, the operator can set the prohibited time while viewing the diagnostic image of the subject 15 displayed on the display unit 13. In particular, the operator can also make a setting that shortens the prohibition time in the HPRF state. By setting the prohibition time in the HPRF state short, the operator can finely set conditions such as the transmission time interval PRT and the reception time interval Tdepth. Therefore, it is possible to set conditions that match the tissue structure of the subject. In the case of a normal PRF state, the operator can also make a setting so that the prohibition time becomes longer. Even when a condition such as the transmission time interval PRT and the reception time interval Tdepth is set so that the HPRF state is set again by setting the prohibition time longer in the normal PRF state, the display on the display unit Degradation of image quality can be prevented.

  The method of setting the prohibited time zone C or C ′ by the operator is to enter a numerical value in the prohibited time input unit 16 or the depth of the position marked by displaying the cursor displayed on the display unit 13. The time corresponding to is set as the prohibited time zone.

1 shows a configuration according to an implementation of an ultrasonic diagnostic apparatus of the present invention. It is an example of the diagnostic process image displayed on the display part of an ultrasonic diagnosing device. It is the figure which showed the transmission timing of the ultrasonic pulse of an ultrasonic diagnostic apparatus, and the reception timing of an echo signal, (a) is the state of normal PRF, (b) is the state of HPRF, (c) is the state of normal PRF It is. It is the figure which showed the transmission timing of the ultrasonic pulse of the ultrasonic diagnostic apparatus, and the reception timing of the echo signal. It is the figure which showed the transmission timing of the ultrasonic pulse of the ultrasonic diagnostic apparatus, and the reception timing of the echo signal. It is the figure which showed the transmission timing of the ultrasonic pulse of an ultrasonic diagnostic apparatus, and the reception timing of an echo signal, (a) is the state of normal PRF, (b) is the state of HPRF, (c) is the state of normal PRF It is.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Ultrasonic diagnostic apparatus, 2 ... Ultrasonic probe, 3 ... B mode signal generation part, 4 ... D mode signal generation part, 5 ... Control part, 6 ... Input device, 7 ... DSC, 8 ... Pulse repetition frequency setting part , 9 ... Sample volume position setting unit, 10 ... Prohibited time setting change unit, 11 ... Pulse repetition frequency input unit, 12 ... Sample volume position input unit, 13 ... Display unit, 14 ... Transmission / reception unit, 15 ... Subject, 16 ... Prohibited time input section

Claims (6)

The ultrasonic pulse is repeatedly transmitted to the subject based on the transmission time interval corresponding to the pulse repetition frequency, and the echo signal from the subject is transmitted based on the reception time interval corresponding to the sample volume at the predetermined position of the subject. An ultrasonic diagnostic apparatus having an ultrasonic probe for receiving,
The ultrasonic probe includes a time during which an ultrasonic pulse is transmitted to the subject, and a predetermined prohibition time that is changed by the prohibition time setting change unit based on the value of the prohibition time input to the prohibition time input unit During, the ultrasonic probe does not receive an echo signal from the subject,
The length of the prohibited time is different between a normal PRF state in which the transmission time interval is longer than the reception time interval and an HPRF state in which the transmission time interval is shorter than the reception time interval.
Ultrasonic diagnostic equipment.   The ultrasonic diagnosis according to claim 1, wherein in the normal PRF state in which the transmission time interval is longer than the reception time interval, the prohibition time is longer than in the HPRF state in which the transmission time interval is shorter than the reception time interval. apparatus. An ultrasonic probe repeatedly transmits an ultrasonic pulse to a subject based on a transmission time interval corresponding to a pulse repetition frequency, and the subject based on a reception time interval corresponding to a sample volume at a predetermined position of the subject An ultrasound diagnostic image generation method for receiving an echo signal from the ultrasound probe and generating a diagnostic image of the subject based on the echo signal received by the ultrasound probe,
The ultrasonic probe does not receive an echo signal from the subject during a predetermined prohibition time including a time during which an ultrasonic pulse is transmitted to the subject,
The length of the prohibited time is different between a normal PRF state in which the transmission time interval is longer than the reception time interval and an HPRF state in which the transmission time interval is shorter than the reception time interval.
Ultrasonic diagnostic image generation method.   The ultrasonic diagnosis according to claim 3, wherein in the normal PRF state in which the transmission time interval is longer than the reception time interval, the prohibition time is longer than in the HPRF state in which the transmission time interval is shorter than the reception time interval. Image generation method.   The ultrasonic diagnostic image generation method according to claim 3, wherein the prohibition time can be set and changed. The ultrasonic diagnostic image generation method according to claim 5, wherein the prohibition time can be set and changed to a value designated by an operator.

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