JPS5854936A - Ultrasonic diagnostic apparatus - 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 The present invention relates to an ultrasonic diagnostic apparatus that can also measure blood flow velocity.

Ultrasonic diagnostic apparatuses are basically based on transmitting an ultrasonic beam into the body of a subject and receiving the reflected waves to obtain an echo signal. Since each tissue in the body has a different reflectivity for ultrasonic waves, the position of the instrument can be determined by knowing the magnitude of the echo signal. A conventional ultrasound diagnostic device uses an ultrasonic beam to scan a single tomographic plane set inside the body to determine the reflectance distribution, and displays this on a television or monitor as a 1i-B mode tomographic plane. I am trying to display it on the device. When ultrasonic waves are reflected by the blood flow in blood vessels in the body, the frequency of the reflected waves varies depending on the flow velocity.
Ugrasiv) 1 received. An ultrasonic diagnostic apparatus that utilizes this to also measure blood flow velocity is known. However, in the conventional method, a single ultrasound beam is sent toward the blood fiK, and the reflected waves that return parallel to the beam direction are received to keep the blood flow velocity constant. The drawback was that only the velocity component in the beam direction could be measured.

The object of the present invention is to provide an ultrasonic diagnostic apparatus capable of measuring the absolute velocity and direction of blood flow.

While i1! In Figure 0, an array transducer 2 consisting of a large number of ultrasonic transducer elements is in close contact with the body surface of a subject. K is given so that an ultrasound beam is transmitted into the body 1.

Further, a receiving circuit 4 is connected to each element, and echo signals from each element are sent to the receiving path 4. The control circuit 6 controls the directivity of the ultrasonic beam when transmitting and receiving it, and the r-t circuit described later, and controls the amount of delay of the /f pulse given to each element by the ultrasonic beam. Determine the deflection and focus tube of the transmitted ultrasound beam and perform it electronically. Further, the receiving circuit 4 includes a transport circuit and a detection circuit, and determines the amount of delay of the echo signal from each element based on the data, thereby controlling the deflection and focus of the delivered ultrasonic beam. Do it electronically. First, a linear electronic scan is performed and a signal obtained from the receiving circuit 4 is sent to a display device 6 such as a telescope or a monitor, and a one-mode tomographic image showing blood vessels 18, etc. displayed above.

Horizontal lit #i is the same as the configuration of a normal linear electronic scanning ultrasound diagnostic device, but according to Honjitsu WAK, the blood flow velocity measurement site is further set while viewing the B-mode image tube on the display device 6. A setting device 7 consisting of a switch, a variable resistor, etc., which can be adjusted, is provided. A direction determining circuit 8 is provided which determines the direction seen from the element O glue 7'21. and the speed signal is sent to the Ji1 circuit 12. Then, the control circuit controls the drive circuit 8 so that the ultrasonic beam is deflected and focused from the first drum 7'21 toward the measurement site. Among the reflected waves from the blood flow 14 at the measurement site, the reflected waves that return in the opposite direction to the direction of the transmitted ultrasound beam are received by the INI group 21, and the reflected waves in other directions are received by the second group 21. The wave is received by the group 22. Echo signals from each element of the group 21 of ml are input to the receiving circuit 4. Further, echo signals from each element of the second glue f22 are input to a receiving circuit 9 similar to the receiving circuit 4. In this way, the receiving circuit 4.
9, an echo No. 45 from the direction of the blood flow 14 at the force measurement site is taken out. Further, the dirt circuit included in these receiving circuits 4.9 is braked by the control circuit 5, and the blood fi
The goo l-circuit is opened only when the reflected wave from 14 reaches each group 21.22. Therefore, the signal passing through this y-t circuit is the echo signal of the reflected wave reflected in two directions among the reflected waves reflected by the blood tlt, 14. These echo signals have their frequencies depending on the speed of the blood flow 14, so the DOAG signal is generated according to the amount of shift. signal extraction circuit 10.
Extract with 11.

Since these Y and f signals represent velocity components in two directions, the absolute velocity of the blood flow 14 and its direction can be determined by synthesizing them using the velocity synthesis circuit 12. ζ Absolute velocity and direction +i determined by
It is displayed on the screen of the display device 6 as an arrow or as a vector at a gray level, and is displayed in line with the blood vessels 18 and the like.

In the above embodiment, a receiving circuit 9 is provided in addition to the receiving circuit 4, but similar echo signals from two directions can be obtained by switching one receiving circuit.

As described above with respect to the embodiments, according to the present invention, two group tubes separated from each other among the many elements of the array transducer are used, and an ultrasonic beam is transmitted from one group toward the measurement site. However, since both groups receive the reflected waves, it is possible to detect the velocity components of blood flow in two directions, and from this, the absolute velocity and direction of blood flow can be determined. The speed of blood flow in abdominal arteries, veins, and carotid arteries can be determined effectively.

[Brief explanation of the drawing]

The figure is a professional diagram of one embodiment of the present invention. 1...body, 18...blood vessels, 14...
Blood flow, 2...Array transducer, 8...
Drive circuit, 4.9...Receiving circuit, 5...Control circuit, 6...Display device, 7...Setting device, 8-Direction determining circuit, 10.11...Dougra signal extraction circuit , 12.-speed synthesis circuit. Applicant: Toritsu Seisakusho Co., Ltd.

Claims (1)

[Claims] 11) An array transducer consisting of a large number of ultrasonic transducers arranged in parallel, and each element having 74
a drive circuit that applies a pulse delay and drives the element; a receiver circuit that is connected to each of the elements and receives an echo signal obtained from each element; A control circuit that electronically controls the directivity of the ultrasonic beam during transmission and reception by changing the amount of delayed echo signals obtained from each element, and a JB
In an ultrasonic diagnostic apparatus comprising a display device for displaying a mode tomographic image T-mode, a setting means for setting a scooping region of blood flow velocity, a first group of elements of the play transducer, and a first group of elements of the play transducer; ! a direction determination circuit that determines the direction of each of the defined portions as seen from the group of #12 elements separated from , a signal extraction circuit that extracts Doppler signal tubes from gain and loss signals from the receiving circuit, and a speed synthesis circuit. the control circuit is controlled by the direction determining circuit to transmit waves from the ultrasonic beam tube from the first group of the elements toward the scooping site, and send the reflected waves to the first group of the elements. glue! and a second group, respectively, and the receiving circuit and the driver! are received by the respective echo signals obtained from these groups. Doppler signal tubes representing velocity component tubes in two directions of the blood flow velocity are extracted by the signal extraction circuit tube, and the absolute velocity and direction of the blood flow are determined by the velocity synthesis circuit.1-Characteristics Ultrasonic diagnostic equipment.