JPH0428379B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to an ultrasonic diagnostic apparatus, and more particularly to a puncture needle type ultrasonic diagnostic apparatus that performs image display diagnosis of directly adjacent tissue within a test tissue of a subject.

[Prior Art] Conventionally, ultrasonic diagnostic devices emit an ultrasonic beam from the body surface of the subject into the subject's body, and receive reflected waves reflected within the body to obtain information within the subject's body. Common. In addition, in order to perform ultrasound diagnosis from a position closer to the tissue to be examined, a probe equipped with an ultrasound transducer is inserted into the body cavity to transmit and receive ultrasound beams from inside the body to perform ultrasound diagnosis. Internally inserted ultrasound diagnostic devices are also known.

This type of ultrasound diagnostic device that can be inserted into a body cavity is
For example, an ultrasound probe is inserted into the rectum to diagnose the prostate gland. An ultrasonic beam of 3 to 10 MHz is used from the probe of such a diagnostic device so that the ultrasonic pulse reaches a desired depth.

On the other hand, conventional ultrasound technology for puncturing a puncture needle for deep treatment and diagnosis of a subject is aimed at accurately inserting the puncture needle toward the target tissue.For example, it is used on the body surface. A device is known that performs safe and reliable puncture using a probe having a puncture hole through which a puncture needle passes through as a monitor, using a probe having a puncture hole through which a puncture needle is passed through as a monitor.

[Problems to be Solved by the Invention] According to the probe inserted into the body cavity, ultrasonic diagnosis can be performed from inside the subject. However, since ultrasonic diagnosis is not performed by directly puncturing the tissue to be examined, it is necessary to transmit an ultrasonic beam at a frequency that reaches a predetermined depth. In other words, it is necessary to set the frequency of the ultrasound beam so that the ultrasound beam can reach the tissue suspected of having a lesion from the probe inserted into the body cavity. is used. When using an ultrasonic beam with such a relatively low frequency, it is possible to ensure a penetration depth of the ultrasonic beam of about 15 cm to 3 cm, but there is a problem in that high resolution cannot be obtained.

In other words, in order to obtain high resolution, for example, in order to be able to diagnose the level of red blood cells, a resolution that can discriminate down to about 10μ is required, and the frequency is
It needs to be around 400-500MHz. However, when such a high frequency ultrasound beam is used, the penetration depth is approximately 0.2 to 0.5 mm, making it impossible to diagnose tissues far from the body cavity into which the probe is inserted. Therefore, in the case of a probe inserted into a body cavity,
In order to ensure a certain level of penetration depth, an ultrasonic beam with a relatively low frequency is used, and it is not possible to perform detailed image diagnosis of tissues with a high resolution at the microscopic level.

In addition, with conventional puncture needles, ultrasound image diagnosis is not performed by emitting an ultrasound beam directly from the puncture needle punctured into the tissue to be examined, but by using an ultrasound probe for puncturing the patient from the body surface. The puncture operation is performed by diagnosing the inside and visually confirming the location to be punctured with the puncture needle. Therefore, similar to an ultrasound diagnostic apparatus using a probe inserted into a body cavity, there is a problem that the frequency of the ultrasound beam cannot be increased in order to improve the resolution to the microscopic level.

Purpose of the Invention The present invention was made to solve the above-mentioned problems, and its purpose is to directly insert an ultrasonic oscillator into the tissue to be examined and perform ultrasonic diagnosis of the tissue to be examined at a microscopic level. It is an object of the present invention to provide a puncture needle type ultrasonic diagnostic device that can perform diagnosis with high resolution.

[Means for Solving the Problems] In order to achieve the above object, the puncture needle type ultrasound diagnostic device according to the present invention includes a hollow trocar that is punctured into the tissue to be examined, and a hollow trocar that is inserted into the trocar. A probe needle whose conical tip protrudes from the opening at the tip of the trocar and is inserted into the tissue to be examined and is rotatable around the needle axis; an ultrasonic transducer that receives ultrahigh-frequency sound waves capable of obtaining microscopic-level resolution into the tissue to be examined in proximity to the tissue, and receives the reflected waves; A damper material that attenuates and absorbs ultrasound emitted from the back surface, a surface coating material that is provided on the front side of the ultrasound transducer and functions as an acoustic lens that focuses ultrasound waves, and a vertical movement distance of the probe needle. or a position detection means for detecting a rotation angle, a transmitting circuit for transmitting the ultrahigh frequency sound wave from the ultrasonic transducer, and a receiving circuit for receiving reflected waves received by the ultrasonic transducer;
image display means for displaying a microscopically enlarged image of the test tissue based on the output signal from the receiving circuit and the vertical distance signal or rotation angle signal of the probe needle from the position detector; It is characterized in that an image is displayed while moving the probe up and down or rotating it.

[Function] According to the above configuration, the probe needle, which has one ultrasonic transducer at its tip that transmits and receives ultrahigh-frequency sound waves, is inserted through the tip opening of the hollow trocar punctured into the tissue to be examined. The probe is inserted protrusively into the tissue to be examined, and an ultrasonic beam can be transmitted from the ultrasonic transducer at the tip of the probe to the tissue to be inspected close to the outer periphery of the probe. In this case, since the tip of the probe needle is formed into a conical shape, the probe needle can be easily protruded into the tissue in front of the probe in a state where the trocar is punctured.

Here, the ultrasound beam can be transmitted directly to the tissue to be examined that is in contact with the outer periphery of the probe needle, and in order to perform ultrasound diagnosis of this tissue, the penetration depth of the ultrasound beam must be An extremely small one is sufficient. Therefore, it is not necessary to ensure a large penetration depth of the ultrasonic beam, so it is possible to increase the frequency of the ultrasonic beam in order to obtain a high-resolution image on a microscopic level. Further, since a damper material is provided on the back side of the ultrasonic transducer, it is possible to absorb unnecessary ultrasonic waves emitted from the back side and effectively prevent noise generated in the received signal. Furthermore, a surface coating material that functions as an acoustic lens is provided on the ultrasonic emission surface side (front side) of the ultrasonic transducer, which prevents the ultrasonic beam from spreading unnecessarily and improves the reception signal. It becomes possible to improve the level.

In addition, since the probe needle is attached to the trocar so that it can move up and down or rotate around the needle axis, the probe needle can be moved up and down or rotated within the tissue to be examined while transmitting and receiving ultrasound beams. By doing so, it is possible to obtain an image of the outer periphery of the position where the ultrasonic transducer of the probe needle is installed, that is, a cross-sectional image of a predetermined depth corresponding to any movement distance or rotation angle. .

In this way, microscopic image information of the tissue can be obtained using the ultrasonic beam's microscopic resolution, and by displaying an enlarged image based on this, tissue diagnosis such as the presence or absence of a lesion can be performed more accurately. I can do it.

[Embodiments] Hereinafter, preferred embodiments of the present invention will be described based on the drawings.

FIG. 1 shows a partial perspective view of the tip of the trocar and probe needle, which are the characteristic components of the present invention.
The trocar 10 has a hollow structure, and its tip is tapered to an acute angle to facilitate puncturing into the subject. The probe needle 12 is a trocar needle 1
It is inserted into the inside of 0, and the tip part is configured to protrude from the tip opening 10a. Here, since the tip of the probe needle 12 is formed into a conical shape, the probe needle inserted inside the trocar 10 can easily protrude into the anterior tissue while the trocar 10 is puncturing the tissue. .

An ultrasonic oscillator 14 is provided at the tip of the probe needle 12.
is provided. The front shape of the oscillating section 14 can be configured in any desired shape, such as a circular shape as shown in FIGS. 1A and 1B, or a rectangular shape as shown in FIG. 1C.

FIG. 2 is a diagram showing a cross section of the ultrasonic oscillating portion 14 of the probe needle 12, which has a solid structure in this embodiment, but may also have a hollow structure.
The ultrasonic oscillator 14 is attached to the peripheral wall of the probe needle 12 so as to transmit an ultrasonic beam outward. A surface coating material 18 is provided on the surface side of the probe needle 12 with the ultrasonic transducer 16 in between, and a damper material 20 is provided on the inner surface side of the ultrasonic transducer 16. Here, the surface coating material 18 also functions as an acoustic lens to focus the ultrasonic beam, and the damper material 20 acts as an acoustic absorption attenuator for the ultrasonic waves emitted from the ultrasonic transducer 16 to the back surface. It functions to prevent it from being displayed on the given image.

FIG. 3 is a block diagram showing the main components of the puncture needle type ultrasonic diagnostic apparatus according to the present invention.
A transmission circuit 22 including a high-frequency pulse oscillator is connected to the ultrasonic transducer 16 provided at the tip of the ultrasonic transducer 16, and the ultrasonic transducer 16 transmits high-frequency ultra-high frequency sound waves that can obtain microscopic level resolution. Outputs a signal for transmitting waves.

Further, a receiving circuit 24 is connected to the ultrasonic transducer 16, and the receiving circuit 24 is connected to the ultrasonic transducer 16.
It receives the reflected waves received by the receiver and performs amplification, A/D conversion, etc. The output signal from this receiving circuit 24 is sent to an image processing circuit 26, and the image processing circuit 26 performs signal processing for displaying an ultrasound diagnostic image on the CRT 28. Further, a position detector 30 is provided for detecting the moving distance or rotation angle of the probe needle 12 provided with the ultrasonic transducer 16, and the moving distance or rotation angle signal from this position detector 30 is also provided. It is supplied to the image processing circuit 26. The image processing circuit 26 displays, on the CRT 28, an image of a predetermined area according to the moving distance or rotation angle signal based on the signal from the receiving circuit 24.

Next, the operation of this embodiment will be explained.

First, the trocar 10 is punctured into the tissue to be examined of the subject. At this time, the probe needle 12 is kept in a state in which it does not protrude from the tip opening 10a of the trocar 10.
That is, the trocar 10 is inserted into the tissue to be examined in the state shown in FIG. Then, the probe needle 1 is
2 and insert the tip into the tip opening 1 of the trocar 10.
The ultrasonic oscillator 1 is made to protrude from 0a and into the tissue to be examined.
Insert 4.

Then, the ultrasonic oscillator 14 transmits a high-frequency ultrasonic beam capable of obtaining microscopic-level high resolution, for example, an ultrasonic beam with a frequency of about 400 to 500 MHz, toward the tissue to be examined. At this time, in order to obtain an image of a predetermined area around the probe needle 12, the probe needle 12 is manually or mechanically moved up and down or rotated around the needle axis within the puncture needle 10. This moving distance or rotation angle is detected by the position detector 30 and sent to the image processing circuit 26. According to the ultrasonic beam having a frequency of 400 to 500 MHz, the penetration depth into the tissue is about 0.2 to 0.5 mm, but the resolution is high, so it is possible to display images down to the level of red blood cells of about 10 microns.

The transmitted high frequency ultrasonic beam is received by the ultrasonic transducer 16, passes through the receiving circuit 24 and the image processing circuit 26, and is displayed as an image on the CRT 28. For this image display, any area can be set by linear scanning by vertical movement of the probe 12 or radial scanning by rotation, but the vertical movement speed or rotation speed can also be set arbitrarily, and low speed It is also possible to obtain high resolution by scanning with . For example, when displaying an image by rotating the probe 12 by 360 degrees, if the penetration depth of the ultrasonic beam is approximately 0.5 mm, a portion of tissue with a width of 0.5 mm in the depth direction around the probe needle 12 will be displayed. Cross-sectional images can be displayed. Although the width is as narrow as 0.5 mm, it is possible to directly display a cross-sectional image of the examined tissue with high resolution (discrimination of about 10 μm is possible), so it is possible to determine whether there is a lesion in the examined tissue, such as cancerous tissue. It is possible to more accurately determine whether or not.

[Effects of the Invention] As explained above, according to the puncture needle type ultrasonic diagnostic apparatus according to the present invention, the ultrasonic oscillator can be inserted directly into the tissue to be examined using the probe needle. There is no need to ensure the penetration depth of the ultrasound beam, and ultrasonic image diagnosis becomes possible using high-frequency ultrahigh-frequency sound waves that have a small penetration depth but can provide microscopic-level resolution. Thereby, ultrasonic image diagnosis can be performed by obtaining minute image information of the tissue to be examined. Therefore, the reliability of diagnosis of lesions, etc. of the tissue to be examined is further improved. In addition, in the present invention, since the damper material and the surface coating material are provided, unnecessary ultrasonic waves emitted from the back side of the ultrasonic transducer can be effectively absorbed while emitted from the front side of the ultrasonic transducer. It is possible to effectively focus the transmitted ultrasound waves. This makes it possible to improve the accuracy of the received signal.

[Brief explanation of drawings]

Figures 1A to C are perspective views of the tip of the puncture needle and probe needle of the embodiment, Figure 2 is a cross-sectional view of the tip of the probe, and Figure 3 is a block diagram showing the main configuration of the embodiment. FIG. 4 is a perspective view showing the puncture needle when puncturing the tissue to be examined. DESCRIPTION OF SYMBOLS 10... Surrogate needle, 12... Probe needle, 14... Ultrasonic oscillation part, 16... Ultrasonic transducer, 18... Surface coating material, 20... Damper material, 22... Transmission circuit, 24
...receiving circuit, 26...image processing circuit, 28...CRT,
30...Position detector.

Claims (1)

[Scope of Claims] 1. A hollow trocar that is punctured into the test tissue; a needle shaft that is inserted into the trocar and has a conical tip protruding from the distal opening of the trocar into the test tissue; It has a centrally rotatable probe needle, and one probe is installed on the outer wall of the tip of the probe needle to transmit ultra-high frequency sound waves capable of obtaining microscopic level resolution to the sample tissue close to the outer periphery of the probe needle. an ultrasonic transducer that receives the reflected waves; a damper material provided on the back side of the ultrasonic transducer that attenuates and absorbs the ultrasonic waves emitted from the back surface of the ultrasonic transducer; and a front side of the ultrasonic transducer. a surface coating material that functions as an acoustic lens that focuses ultrasonic waves; a position detection means that detects the vertical movement distance or rotation angle of the probe needle; a transmitting circuit for transmitting a signal; a receiving circuit for receiving a reflected wave received by the ultrasonic transducer; and an output signal from the receiving circuit and a probe needle vertical distance signal or rotation angle signal from the position detector. an image display means for displaying a microscopically enlarged image of the test tissue based on the following: A puncturing needle type ultrasound characterized by displaying the image while vertically moving or rotating the probe needle. Diagnostic equipment.