JPH0654850A - Ultrasonic diagnostic device - Google Patents

Abstract

PURPOSE:To obtain living body information in the periphery of a target part of a diagnosis, and also, to prevent deterioration of sensitivity by controlling a frequency of an ultrasonic wave transmitted from an ultrasonic transmitting/ receiving means in accordance with depth from the surface of a living body in a focus position, a color display area of a Doppler signal detecting position. CONSTITUTION:A system controller 12 determines a frequency of an ultrasonic wave transmitted from an ultrasonic probe 15 in accordance with depth from the surface of a living body in a focus position, a color display area or a Doppler marker from an operating panel 11. That is, it is determined so that an ultrasonic wave of a low frequency, and an ultrasonic wave of a high frequency are transmitted in the case it is positioned in a deep part in a visual field, and in the case it is positioned in a shallow part, respectively. In such a way, in the case the focus position is set in a deep position in a visual field, a deeper part can be obtained as an image, and even in the case a color display area of a Doppler signal detecting position is set in a deep position in the visual field, deterioration of sensitivity can be prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultrasonic diagnostic apparatus for scanning a cross section of a subject with ultrasonic waves to obtain a tomographic image.

[0002]

2. Description of the Related Art Conventionally, an ultrasonic diagnostic apparatus has been used for medical diagnosis in order to obtain biological information of a patient. This ultrasonic diagnostic apparatus transmits an ultrasonic pulse from an ultrasonic probe into a living body, receives a reflected wave from a boundary surface of a tissue having different acoustic impedances by the same ultrasonic probe, and converts it into an electric signal. Then, a tomographic image is displayed on the monitor based on the electric signal.

The depth from the surface of the living body where a diagnostic image can be obtained in such an ultrasonic diagnostic apparatus, that is, the maximum visual field depth, is because the degree of absorption of ultrasonic waves by the living body increases in proportion to its frequency. The higher the frequency of ultrasound, the shallower the diagnosis. However, in order to obtain a high resolution image, high frequency is desired.

Further, in the transmission of ultrasonic waves, in order to improve the resolution of the target region for diagnosis, the target region for diagnosis is focused. However, even if the focus position is set deep in the visual field, the ultrasonic wave is transmitted. Since the frequency of the sound waves is constant, the maximum depth of field is also constant. Also, setting the color display area in the color mode that colors the bloodstream,
Even when setting the Doppler signal detection position in the Doppler mode in which the change state of the blood flow velocity in the set region is displayed as a 1-point Doppler image represented by a waveform, the frequency of the ultrasonic wave to be transmitted is constant regardless of the set position. .

[0005]

In the conventional device as described above, the depth of field does not change even if the focus position is deepened, so that there is a problem in that it is impossible to obtain biological information around the target site for diagnosis. It was Further, in the color display mode and the Doppler mode, there is a problem that if the set area is located deep in the field of view, the sensitivity is lowered due to the attenuation of ultrasonic waves.

Therefore, the present invention eliminates the above-mentioned drawbacks, and an object of the present invention is to provide an ultrasonic diagnostic apparatus for changing the frequency of ultrasonic waves according to the focus position, the color display area or the Doppler signal detection position. Is.

[0007]

In order to achieve the above object, the present invention provides an ultrasonic wave transmitting / receiving means for transmitting an ultrasonic wave and receiving a reflected wave from a sound field and converting the ultrasonic wave into an electric signal. Control means for controlling the frequency of the ultrasonic wave transmitted from the ultrasonic wave transmitting / receiving means according to the focus position, the color display area or the Doppler signal detection position, and a diagnostic image is displayed based on the electric signal from the ultrasonic probe. It is characterized by including a display means for performing.

[0008]

According to the present invention, the frequency of the ultrasonic wave transmitted from the ultrasonic wave transmitting / receiving means is optimally controlled by the control means according to the depth from the surface of the living body at the focus position, the color display area or the Doppler signal detection position. By doing so, when the focus position is set to a deep position within the field of view, a deeper part can be obtained as an image, and even when the color display region or the Doppler signal detection position is set to a deep position within the field of view. It is possible to prevent the sensitivity from decreasing.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment according to the present invention will be described below with reference to the drawings. FIG. 1 shows a configuration example of an embodiment according to the present invention.

The operation panel 11 can set various diagnostic conditions. For example, selection of the diagnostic mode and the like, and further setting of the focus position for obtaining the B-mode image, the color display area in the color display mode, and the position of the Doppler marker (indicating the Doppler signal detection position) in the Doppler mode, etc. can do. The information set by the operation panel 11 is sent to the system controller 12.

The system controller 12 controls the entire system (not shown), and particularly, the ultrasonic probe according to the focus position from the operation panel 11, the color display area, or the depth of the Doppler marker from the living body surface. The frequency of the ultrasonic wave transmitted from 15 is determined. It is determined that low-frequency ultrasonic waves are transmitted when the object is located deep in the visual field, and high-frequency ultrasonic waves are transmitted when the object is located shallow. The ultrasonic probe used in this embodiment has a wide frequency band, for example, 3.75 MH.
It is designed so that ultrasonic waves of z to 7.5 MHz can be transmitted and received.

An example of this determination method will be described with reference to FIG. FIG. 2 shows the case of the sector scan. In addition, in the present embodiment, the frequency of the ultrasonic wave to be transmitted is, for example, 3.75, 5.0, 7.5 MHz.
There are three types. 20 in FIG. 2 is 3.75 MHz
The maximum field of view when the ultrasonic wave is transmitted. The circular arcs 21, 22 and 23 each have an ultrasonic frequency of 3.7.
The maximum depth of field at 5, 5.0, and 7.5 MHz is shown. The arc 24 is set at an arbitrary position in a portion shallower than the arc 23. When the areas surrounded by these arcs are areas 31, 32, 33, and 34, the areas 31 and 3 are
If the focus position, color display area or Doppler marker is set to 2, ultrasonic waves of 3.75 MHz, 5.0 MHz if set to area 33 and 7.5 MHz if set to area 34 Decide to transmit.

By determining the driving frequency of the ultrasonic probe 15 as described above, the maximum depth of field when the ultrasonic wave is transmitted at 5.0 MHz, for example, is the arc 22 in FIG. When set in the region 32, since the ultrasonic wave of 3.75 MHz is transmitted, the maximum depth of field is the arc 21. Therefore, the field of view for the region 31 is increased as compared with the conventional apparatus, and the information of the tissue around the target site for diagnosis is obtained as an image, so the accuracy of diagnosis is improved. In the color display mode and the Doppler mode, the same frequency is determined, and the sensitivity can be improved as compared with the conventional device. The case of the sector scan has been described above, but the method of scanning an ultrasonic wave is not limited.

The transmitting circuit 13 internally generates a basic signal, and the system controller 12 is based on the frequency of the signal.
The trigger signal having the frequency determined by is sent to the high voltage output circuit 14 at a timing based on the delay time sent from the system controller 12. The high voltage output circuit 14 is
This trigger signal is converted into a high-voltage pulse signal and applied to the ultrasonic probe 15. The ultrasonic probe 15 receives the pulse signal and transmits ultrasonic waves into the living body, and
The reflected wave from the living body is received and converted into an electric signal. This electric signal is input to the receiving circuit 16 in the subsequent stage. The receiving circuit 16 is controlled by the system controller 12 at the reception timing similar to the transmission timing, performs predetermined amplification and detection on the electric signal, and sends the electric signal to the image processing apparatus 17. In the image processing device 17, the signal from the receiving circuit 16 is subjected to predetermined processing and displayed as a diagnostic image on the TV monitor 18. Next, the operation of the ultrasonic diagnostic apparatus configured as described above will be described.

A case where the B mode is selected by the operation panel 11 will be described. When the focus position is set on the operation panel, the information is sent to the system controller 12. In the system controller 12, the ultrasonic probe 1 is selected according to the focus position.
The drive frequency of 5 is determined. For example, if the set focus position is in the area 32 in FIG. 2, the frequency is 3.
It is determined to be 75 MHz. This frequency information is sent to the transmission circuit 13. The transmission circuit 13 outputs a trigger signal having a frequency determined by the system controller 12 at a timing based on the delay time sent from the system controller 12. The high voltage output circuit 14 converts the trigger signal into a high voltage pulse signal and applies it to the ultrasonic probe 15. The ultrasonic wave transmitted from the ultrasonic probe 15 upon receiving the pulse signal is reflected by various tissues of the living body, and the reflected wave is received by the ultrasonic probe 15 and converted into an electric signal. This electric signal is input to the receiving circuit 16 in the subsequent stage. The receiving circuit 16 is controlled by the system controller 12 at the reception timing similar to the transmission timing, performs predetermined amplification and detection on the electric signal, and sends the electric signal to the image processing apparatus 17. The image processing device 17 performs a predetermined process and sends it as image data to the TV monitor 18. The TV monitor 18 visually displays the image data.

In the apparatus as described above, if the focus position is set according to the position of the target region for diagnosis, ultrasonic waves of a frequency corresponding to the focus position are transmitted, so that the periphery of the target region for diagnosis is transmitted. The biometric information can be obtained, and an image with excellent resolution can be obtained in the shallow area. In addition, when the focus position is set in a deep part of the field of view, a deeper part of the image can be obtained as an image, so that the diagnostic image can be easily viewed and the diagnostic accuracy is improved.

Also in the color mode and the Doppler mode, the sensitivity can be improved by changing the frequency in the same manner as in the B mode described above depending on the setting position of the color display area or the Doppler marker.

In the embodiment described above, the focus is applied to the position of a certain depth to obtain the image of one frame, but it is also effective in the multi-stage focus. The multi-stage focus is to obtain one frame of image data by sequentially changing the focus position while keeping the frequency of the ultrasonic wave to be transmitted constant, and to obtain a high-resolution image over the entire field of view. Is the way.

In the case of two-stage focusing, while keeping the transmission frequency of ultrasonic waves constant, an image is constructed by first focusing on a short distance in the depth direction of the living body, and then focusing on a long distance. After constructing an image by combining the images for each focus stage on the image memory, one frame of image data is obtained.

In applying the present invention to this method, when the focus position is sequentially changed, the frequency of the ultrasonic wave may be changed according to the position. By doing so, a high-resolution image can be obtained at a deeper position. When a low-frequency ultrasonic wave is transmitted in order to obtain an image at a deep position in a conventional device, the resolution of the shallow portion is inferior, and if an image of high resolution is obtained, the image at the deep portion cannot be obtained. I couldn't get it. However, in the present invention, the high frequency ultrasonic wave is transmitted in the shallow portion, and the low frequency ultrasonic wave is transmitted in the deep portion.
High-resolution images can be obtained over the entire field of view. In the color display mode or the Doppler mode, it is possible to prevent the sensitivity from decreasing due to the setting area.

In the embodiment described above, the ultrasonic wave to be transmitted has three kinds of frequencies, but the present invention is not limited to this, and it is sufficient to have two or more kinds. Further, in multi-stage focusing, the image may be difficult to see due to a partial difference in image resolution, but the frequency of ultrasonic waves to be transmitted may be changed in small increments to increase the types. It should be noted that the present invention is not limited to the above-described embodiments, and can be modified in various ways unless the subject matter described in the claims is changed.

[0022]

As described above in detail, according to the present invention, the frequency of the ultrasonic wave to be transmitted can be changed according to the focus position, the color display area or the Doppler signal detection position.
In the B mode, it is possible to reliably obtain an image around the target site for diagnosis. Further, in the color display mode or the Doppler mode, optimum sensitivity can be obtained according to the color display area or the Doppler signal detection position.

[Brief description of drawings]

FIG. 1 is a configuration diagram of an embodiment according to the present invention.

FIG. 2 is a diagram showing a region of a visual field.

[Explanation of symbols]

 11 Operation Panel 12 System Controller 13 Transmission Circuit 14 High Voltage Output Circuit 15 Ultrasonic Probe 16 Reception Circuit 17 Image Processing Device 18 TV Monitor

Claims (1)

[Claims] 1. An ultrasonic wave transmitting / receiving means for transmitting an ultrasonic wave and receiving a reflected wave from a sound field to convert the ultrasonic wave into an electric signal, and a frequency of an ultrasonic wave transmitted from the ultrasonic wave transmitting / receiving means. An ultrasonic diagnostic apparatus comprising: a control unit that controls according to a position, a color display area, or a Doppler signal detection position, and a display unit that displays a diagnostic image based on the electric signal from the ultrasonic probe.