JPS5886143A - 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.

The ultrasonic diagnostic apparatus is configured to scan a subject with an ultrasonic beam, convert the echo waves reflected from the subject into echo signals, and display the tomographic height of the subject on a monitor based on the echo signals. However, conventional ultrasonic diagnostic equipment displays a two-dimensional distribution of the amplitude of the echo signal as an image on a monitor. However, although this method using only amplitude information is quite effective in morphologically diagnosing the subject, for example, diagnosing the movement of heart valves using an electronic scanning ultrasonic diagnostic device, it is not effective in qualitatively diagnosing the subject. For example, it is not very effective in diagnosing whether the same cancer cell is benign or malignant, and requires a lot of experience on the part of the doctor, and conventional ultrasonic diagnostic equipment cannot accurately perform qualitative diagnosis.

Therefore, an object of the present invention is to provide an ultrasonic diagnostic apparatus that can display not only the morphology but also the quality of a subject.

The present invention will be described in detail below with reference to the drawings, and the nine basic ideas that led to the invention will be described.

When humans judge the form and quality of objects, the eyes play an important role as sensory organs. When we perceive information visually, the difference in absorption, attenuation, reflection, and confusion of light is perceived as amplitude, and at the same time, the difference in absorption, attenuation, reflection, and confusion due to the difference in frequency of light is perceived as color. It will be done. This color information plays an extremely important role when making qualitative judgments about objects. By the way, even in ultrasound diagnosis, as stated on page 1374 of the Ultrasonic Technology Handbook, the amount of ultrasound absorbed by living tissues varies depending on the frequency of the ultrasound.

It is said that malignant cancer cells have a large attenuation due to reflection in high frequency components. Qualitative diagnosis becomes possible by displaying in color the differences in absorption, attenuation, reflection, and confusion of ultrasound waves due to differences in frequency. This invention is accomplished by utilizing such frequency-based characteristics.

In the embodiment shown in FIG. 1, an ultrasonic transducer (ultrasonic transducer) of an ultrasonic scanner 1 is coupled to a drive source 13 such as a motor or a galvano device so as to be oscillated by the drive source 13. Ru. The vibrator 12 also includes an angle detector 1 for detecting the deflection angle of the vibrator 12.
4 is connected. A signal terminal of the vibrator 12 is connected to a switch circuit 15. This switch circuit 15 is a drive
! It is connected to the output terminal of the pulse generator 16 and the input terminal of the preamplifier 17, and is configured to switch between transmission and reception according to a control signal from a control circuit 18. The drive pulse generator 1
6 is controlled by the output of the control circuit 18 and is configured to generate an ultrasonic dry pulse having three frequency bands having center frequencies of three frequencies fl, fs, and fs corresponding to the three primary colors, respectively. . Preamplification 52
7 has a frequency f1. A pantone motherboard filter (
BPF) 19, connected to the input terminals of 20 and 21. These BPF19. :10 and 21 are BPF control circuit 22
．． 28 and 24 VC are connected to each other, and the center frequency, bandwidth, and cutoff characteristics are set semi-fixed. The output terminals of BPFs 19.20 and 21 are connected to a signal processing circuit 28.1 via logarithmic amplifiers 25.26 and 27, respectively.
9 and 30. These signal processing circuits 28゜2
Connected to 9 and 30 are STC voltage generation circuits 31, 32 and 33, which generate a signal voltage that performs temporal gain control to correct the attenuation of ultrasonic waves, that is, 8TC voltage. It is connected to the circuit 34 and the dynamic range control voltage generation circuit 35. Signal processing circuit 28
The output terminals of 29 and 30 are connected to the input terminals of frame memories 37, 311 and 39 of the scan controller 36. The output terminals of the memories 37, 38 and 39 are output terminals R of a color display device, namely a color monitor display 40,
G and B, respectively. A signal output terminal of a sweep signal generation circuit 41 is connected to the X and Y signal input terminals of the monitor display gray 40 . This sweep signal generation circuit 41
is connected to the output end of the angle detector 14 in order to output X and Y sweep signals corresponding to the deflection angle detected by the angle detector 14 of the scanner 1.

Next, the operation of the ultrasonic diagnostic apparatus will be explained.

When power is applied and in response to signals from control circuit 18, drive pulse generator path 16 sets the center frequency f as shown in FIG.
When a drive notarus having frequency bands of t, fs, and fs is generated, this drive notarus is supplied to the ultrasonic transducer 12 via a switch circuit 15. The ultrasonic transducer 12 emits ultrasonic waves corresponding to the frequency band to the subject. Ultrasonic waves that are absorbed, attenuated, reflected, and complexed according to the linear frequency band from the subject are reflected as echo waves. When an echo wave is incident on the vibrator 12, the echo wave is converted into an electric signal, that is, an echo signal, and is input into the preamplifier 17 via the switch circuit 15. The echo signal is amplified by the preamplifier 77 to improve the 8/N ratio, and then sent to the BPF 19. jlO and 21.

BPF 1 jl , 20 and 21 are BPF control circuits 22 . : Frequency band signal components corresponding to the three frequency bands are selected from the echo signal according to the values set by 13 and 24 and are passed through. BPFM! 9 to 21
The signal components passing through are input to logarithmic amplifiers 25 to 21, respectively. The signal components logarithmically amplified by the logarithmic amplifiers 25 to 27 are detected, and the signal components logAX = A! The gain control voltage of the gain control voltage generation circuit 34 and 8
The 8TC voltages of the TC voltage generation circuits 31, 32 and 33 are added to the detected signal component. By the way, attenuation in living tissue is determined by the amplitude of the sound being A, the initial amplitude value being Ao, and the general distance of propagation being x.
1 If the attenuation constant is α, then A=AO6−“X and α is f
l to f” (f is frequency). Therefore, 8TC
Voltage generation circuits 31, 32 and 33 have different frequency bands K
It is necessary to output 8TC voltages that have characteristics that compensate for differences in attenuation caused by the 8TC voltages. That is, an 8TC voltage with an inverse characteristic as shown in FIG. 4 is required, which corrects the characteristic showing the difference in attenuation due to the difference in frequency bands shown in FIG. 3.

The corrected signal component is multiplied by the dynamic control voltage of the dynamic range/zo control voltage generating circuit 35. The signal components subjected to the above-described signal processing in the signal processing circuits 28 to 30 are supplied to frame memories 37 to 39 of the scan converter 36. The signals read out from the frame memories 37 to 39 are input to terminals R2B and GK of the color monitor display 40 as R, G, and B signals. The color monitor display gray 40 is an X from the sweep signal generating circuit 41.

The scanning of R and G is controlled by the Y sweep signal.

Displays the B signal as color III. By observing this color image, it is possible to accurately diagnose whether cancer cells are malignant or benign.

As explained above, according to the present invention, an ultrasonic transducer is driven by a drive pulse having different frequency bands, an echo signal is divided into a plurality of signal components corresponding to different frequency bands, and these signal components are converted into a signal. Since an ultrasonic diagnostic apparatus is provided which processes and displays a color image on a color monitor display Kfl, it is possible to accurately perform not only a morphological diagnosis but also a qualitative diagnosis of the subject, thereby improving the reliability of the diagnosis.

In the above embodiment, the center frequency, bandwidth, and cutoff characteristics of the gundonos filter are set by the BPF control circuit, but the BPF control circuit does not have to vary the respective characteristics depending on the subject. 69. is provided because it is expected that this will not happen. Once color diagnosis software is established, BPF can be fixed. Further, in the embodiment, the number of frequency bands is determined corresponding to the three primary colors, but the number is not limited to the three primary colors.

[Brief explanation of drawings]

Fig. 1 is a circuit diagram of an ultrasonic diagnostic apparatus according to a set of embodiments of the present invention, Fig. 2 is a graph showing the frequency characteristics of the drive pulse, and Fig. 3 is a graph showing the decay time in the living body. , and FIG. 4 is a graph showing the characteristics of the 8TC voltage. 11... Ultrasonic scanner, 12... Ultrasonic transducer, 13... Drive source, 14... Angle detector,
15... Switch circuit, 16... Drive) 4 pulse generation circuit, 17... Preamplifier, 18... Control circuit, 19.20.21... Pantone arm filter, 22
I23.24...BPF control circuit, 25.26°21
... Logarithmic amplifier, 2B, 29.30 ... Signal processing circuit, 3 J, 32.33-8TC voltage generation circuit, 34
...Gain control voltage generation circuit, 35...Dynamic range control voltage generation circuit, 36...Scan converter, 3r*811-39...Frame memory, 40.
・Color monitor display gray. Applicant's agent Patent attorney Takehiko Suzue, Commissioner of the Patent Office
Haruki Shimada 1. Case Display Patent wA5e)”184201 No. 3, Person making the amendment Relationship with the case Patent applicant (037) Orin Gusu Optical Industry Co., Ltd. 4, Agent 5, Voluntary amendment

Claims (1)

[Scope of Claims] 1) An ultrasonic device that generates ultrasonic waves in II several bands whose center frequencies are a plurality of frequencies corresponding to a plurality of primary colors, and converts the ultrasonic echo waves reflected from a subject into echo signals. a sonic transducer; 1 a filter means for dividing an echo signal of the ultrasonic transducer into frequency signal components corresponding to the plurality of bands; and a signal processing means for processing the frequency signal components of the filter means 25λ and the like; , the signal processor 1! An ultrasonic diagnostic apparatus comprising color display means for displaying the frequency signal components processed by IK as a color display. 2) The ultrasonic transducer generates three bands of ultrasonic waves whose center horse wave numbers are three frequencies corresponding to each color, and the filter means converts the echo signal into three bands.
1. The ultrasonic diagnostic apparatus according to claim 1, which comprises a pantonous filter that divides into frequency band components corresponding to colors. 3) The signal processing circuit assumes means for processing the frequency signal component by a signal having a characteristic different from the attenuation characteristic in order to correct the difference in ultrasonic attenuation due to the difference in the band. Or the ultrasonic diagnostic device according to item 2.