JPH04220244A - Intracelial ultrasonic diagnostic device - Google Patents

Abstract

PURPOSE:To obtain good ultrasonic images by efficiently decreasing the noise arising in an observation device from a separate appliance without increasing the diameter of an ultrasonic probe and without hardening the probe. CONSTITUTION:This intracelial ultrasonic diagnostic device 1 uses the observing device 2 having the ultrasonic probe 6 to be inserted into the body cavity, a probe driving section 7 for driving this ultrasonic probe 6 and an ultrasonic observing section 8 displaying the ultrasonic diagnosing image of the intra-body section by the signals obtd. by driving the ultrasonic probe 6 with this probe driving section 7 together with appliances, such as light source 3 and endoscope 4, separate from this observing device 2. The above-mentioned device has a conducting means of maintaining the same potential by connecting a GND terminal 16 which is provided in the probe driving section 7 and is connected to the ground of the observing device 2 and the ground of the above-mentioned appliances 3, 4 by, for example, a cable 18.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an intrabody cavity ultrasonic diagnostic apparatus for diagnosing an organ, etc. by inserting a transmitting/receiving ultrasonic probe into the body cavity to obtain an ultrasonic diagnostic image of the organ.

0002

[Prior Art] Conventionally, ultrasonic waves are emitted toward a site within a body cavity, and reflected waves generated due to differences in acoustic impedance within the body cavity are received. 2. Description of the Related Art Intrabody cavity ultrasound diagnostic devices that observe and diagnose conditions inside the body cavity are known. This includes, for example, an ultrasound probe that is inserted into a body cavity, a probe drive unit that connects to and drives this ultrasound probe, and a probe drive unit that connects with this probe drive unit to generate an ultrasound diagnostic image of a site inside the body cavity. It is composed of an observation device having an ultrasonic observation section for displaying images, and a device separate from this observation device, such as an endoscope or a light source device. By the way, in order to diagnose, for example, a stenosis in a body cavity that cannot be observed with a general ultrasound probe, a small-diameter ultrasound probe is required. However, when making a diagnosis by inserting this small-diameter ultrasound probe into the channel of an endoscope, for example, the ultrasound signal received by the ultrasound transducer at the tip of the ultrasound probe is extremely small. , the received signals are easily affected by noise emitted by equipment such as endoscopes and light source devices that are separate from the observation equipment such as the ultrasound probe, and therefore good ultrasound images cannot be obtained. There is a risk that accurate diagnosis may not be possible.

[0003] Therefore, as a noise countermeasure on the side of observation equipment such as an ultrasonic probe, the shielding of the receiving signal line of the ultrasonic probe is strengthened, or an amplifier is installed in the ultrasonic transducer section at the tip of the ultrasonic probe. ing. Also,
Preventing noise from entering the ultrasound probe from devices connected to the endoscope, such as light source devices and video processors, by preventing noise from entering the endoscope as much as possible.In other words, reducing noise from the endoscope side It is not impossible to think of countermeasures. That is, normally, as a safety measure (feedback of leakage current) when using an electric scalpel, from the distal end 101 of the endoscope 100 to the curved part 102, the flexible tube 103, the operating part 104, the ground cord 106 in the universal cord 105, and the connector 107. A conduction means 111 is provided to electrically connect the endoscope to the E terminal 108 (see FIG. 16). However, when an ultrasound probe is inserted into an endoscope, a device connected to the endoscope, such as a light source, is provided. Because noise from the equipment and video processor can easily get onto the ultrasound probe through the endoscope, Figure 1
As shown in FIG. 6, a switch 10 is connected to the connection between the earth cord 106 in the universal cord 105 and the operating section 104.
9 is provided, and when using an electric scalpel, turn on the switch 109 to ensure the return of leakage current, and when using an ultrasonic probe, turn off the switch 109 to block external noise coming into the endoscope 100 through the universal cord 105. It is something to do.

0004

[Problem to be solved by the invention] By the way, in the case of noise countermeasures on the observation equipment side, if the shielding of the receiving signal line of the ultrasonic probe is strengthened as described above, the ultrasonic probe becomes thicker and it is difficult to reduce the diameter of the probe. Not only that, but the probe itself becomes hard, which may cause problems in diagnosis. Furthermore, when an amplifier is provided at the tip of the ultrasonic probe, there is a risk that the amplifier may become an obstacle to reducing the diameter of the probe, or the hard portion at the tip of the probe may become longer. Additionally, while noise countermeasures are of course necessary on the endoscope side, they cannot be fully effective without noise countermeasures on the line that directly affects ultrasound images, that is, on the observation equipment side. Therefore, noise countermeasures on the observation equipment side are inevitably required. Therefore, in the end, between each device in the ultrasound diagnostic equipment,
Multiple measures must be taken to prevent noise from being transferred from one device to the other, resulting in inefficiency as a noise countermeasure.

The present invention has been made in view of the above-mentioned circumstances, and its purpose is to efficiently reduce noise from a separate device to an observation device without increasing the diameter and hardness of the ultrasonic probe. It is an object of the present invention to provide an intra-body cavity ultrasonic diagnostic device that can obtain good ultrasonic images with good reduction.

[0006]

[Means for Solving the Problems] In order to solve the above problems, the present invention provides an ultrasonic probe inserted into a body cavity;
An observation device having a probe driving section that drives the ultrasound probe, and an ultrasound observation section that displays an ultrasound diagnostic image of an internal body part using a signal obtained by driving the ultrasound probe with the probe driving section. In an intrabody cavity ultrasound diagnostic device used with a device such as an electric light source that is separate from this observation device, a ground terminal connected to the ground of the observation device and this ground terminal and the ground of the device are connected. and a conduction means for making the same potential.

[0007]

[Operation] With the above configuration, the observation device has the same potential as the ground of a device separate from the observation device, so that the noise transferred from the device to the observation device is reduced.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIGS. 1 and 2 show a first embodiment of the present invention.

The intracorporeal ultrasound diagnostic apparatus 1 of this embodiment includes an observation device 2, a light source device 3 separate from the observation device 2, and an endoscope 4 connected to the light source device 3. The observation device 2 includes an ultrasound probe 6 that is inserted into a body cavity through a channel 5 of an endoscope 4, a probe drive unit 7 that connects to and drives the ultrasound probe 6, and a probe drive unit 7 that connects to and drives the ultrasound probe 6. and an ultrasound observation section 8 that is connected to and displays ultrasound diagnostic images of internal parts of the body. The ultrasonic probe 6 is
For example, it can be attached to and detached from the probe drive unit 7 by a connector 9. The endoscope 4 includes an operating section 4a and an insertion section 4b, and a light guide cord 10 is connected to the operating section 4a. The endoscope 4 and the light source device 3 are connected by connecting the connector 11 provided at the end of the light guide cord 10 to the endoscope light source device 3.

The tip portion 6a of the ultrasonic probe 6 is shown in FIG.
As shown in the figure, an ultrasonic transducer 12 that transmits and receives ultrasonic waves is provided, and this ultrasonic transducer 12 includes a flexible shaft 13 that transmits rotational driving force from a motor provided in the probe drive unit 7. and a signal cable 14 for ultrasonic transmission connected to the ultrasonic observation section 8 via the probe drive section 7 and a cord 15. In addition to the motor, an encoder for position detection and a preamplifier are provided in the probe drive unit 7.

Ultrasonic transducer 12 at the tip of ultrasonic probe 6
is driven by high-voltage pulses applied from the ultrasonic observation section 8 via the signal cable 14, and is capable of emitting ultrasonic waves to internal parts of the body and receiving reflected waves thereof. Further, this radial scan is performed by transmitting the rotation of the motor in the probe drive unit 7 to the ultrasonic transducer 12 through a flexible shaft 13 made of, for example, a closely wound metal coil in the ultrasonic probe 6. . That is, the ultrasonic transducer 12 receives reflected waves of ultrasonic waves emitted by itself while rotating, and this received signal is transmitted to the ultrasonic observation section 8 via the signal cable 14 to obtain an ultrasonic diagnostic image. . Note that during the transmission, the received signal is amplified by the preamplifier (not shown) provided in the probe driving section 7.

The probe driving section 7 is also provided with a GND terminal 16 that is electrically connected to the ground (hereinafter referred to as GND) of the ultrasonic observation section 8 . This GND terminal 16 is electrically connected to, for example, the flexible shaft 13 of the ultrasonic probe 6. In other words, the GND terminal 16 of the probe drive unit 7 and the GND terminal of the probe drive unit 7 and the ultrasound probe 6
All ND potentials are the same as the GND (ground) potential of the ultrasonic observation unit 8.

On the other hand, the connector 11 of the light guide cord 10 connected to the operating section 4a of the endoscope 4 is provided with a ground terminal (hereinafter referred to as "E terminal") 17. This E terminal 17 is connected to the light guide cord 10 and the endoscope 4 in an electrically conductive state. Specifically, the E terminal 17 is electrically connected to the light guide cord 10 and the endoscope 4, for example, through a blade or a flex tube installed from the insertion portion 4b of the endoscope 4 to the light guide cord 10. There is. Also,
When the connector 11 is connected to the light source device 3, the E terminal 17 is connected to GND of the light source device 3 in an electrically conductive state. In other words, the potential of the E terminal 17, the endoscope 4, and the light guide cord 10 is the same as that of the light source device 3.
It has the same potential as the ground potential.

[0014] The E terminal 17 of the endoscope 4 and the GND terminal 16 of the probe drive unit 7 are electrically connected to each other by a cable 18. In other words, the GND potential on the observation device 2 side and the equipment side such as the endoscope 4 (of course, including the channel 5 into which the ultrasound probe 6 is inserted) and the light source device 3, which are separate from the observation device 2, The potential is the same as the GND potential.

Therefore, in the intrabody cavity ultrasound diagnostic apparatus 1 having the above configuration, the GND on the observation device 2 side and the GND on the equipment side such as the endoscope 4 and the light source device 3 are made to have the same potential through the cable 18, so that ultrasonic When performing ultrasound diagnosis by inserting the sonic probe 6 into the channel 5 of the endoscope 4, the ultrasound probe 6 comes from the equipment side such as the endoscope or light source device to the observation device 2 side, in other words, it comes onto the ultrasound diagnostic image. Noise can be reduced.

Note that without connecting the GND terminal 16 to the E terminal 17, it is possible to connect other GND terminals of equipment separate from the observation device 2.
By connecting to the ND terminal, it is also possible to reduce noise coming into the observation device 2 from the separate devices 3 and 4.

FIGS. 3 and 4 show a second embodiment of the invention. Note that in FIGS. 3 and 4, parts common to those in FIGS. 1 and 2 are denoted by the same reference numerals, and detailed explanation thereof will be omitted.

The intracorporeal ultrasound diagnostic device 25 of this embodiment has the following features:
As in the first embodiment, it consists of an observation device 2, a light source device 3 (not shown in FIG. 3) separate from the observation device 2, and an endoscope 4 connected to the light source device 3. . Endoscope 4
The light source device 3 is connected to the light source device 3 by connecting the connector 11 of the light guide cord 10 connected to the operating section 4a of the endoscope 4 to the light source device 3. The observation device 2 also includes an ultrasonic probe 6, a probe drive section 7, and an ultrasonic observation section 8 (not shown in FIG. 3).

As shown in FIGS. 3 and 4, the outer periphery of the ultrasonic probe 6 extending from the probe drive unit 7 to the entrance of the channel 5 of the endoscope 4 is covered by a cylindrical shielded cable 26. As shown in FIGS. A shielded cable connector 27 serving as a ground terminal is provided at the end of the probe drive unit 7 on the side connected to the ultrasonic probe 6. One end of the shielded cable 26 is electrically connected to the shielded cable connector 27. In addition, the shield cable connecting connector 27 connects the GND of the ultrasonic observation unit 8 and the GND of the ultrasonic probe 6.
It is also electrically connected to the other parts. In other words, the shielded cable connector 27, the shielded cable 26, the probe drive unit 7, and the
All ND potentials are the same as the GND potential of the ultrasonic observation unit 8.

On the other hand, when the endoscope 4 connects the connector 11 of the light guide cord 10 connected to the operation section 4a to the light source device 3, the endoscope 4 is electrically connected to the GND of the light source device 3. It has become so. The end of the shielded cable 26 opposite to the connection side with the connector 27 is connected to the channel 5 of the endoscope 4, and is further connected to a conductive part of the endoscope 4 in an electrically conductive state. ing. In other words, the potentials of the endoscope 4, light guide cord 10, and shield cable 26 are the same as the ground potential of the light source device 3.

Therefore, the potential on the observation device 2 side and equipment such as the endoscope 4 (of course, including the channel 5 into which the ultrasound probe 6 is inserted) and the light source device 3, which are separate from the observation device 2, The potentials on both sides are the same because the observation device 2 side and the equipment sides 3 and 4 are connected to each other by a shielded cable 26.

Therefore, in the intrabody cavity ultrasound diagnostic apparatus 25 having the above configuration, the GND on the observation device 2 side and the GND on the equipment side such as the endoscope 4 and the light source device 3 are made to have the same potential through the shielded cable 26. When performing ultrasound diagnosis by inserting the ultrasound probe 6 into the channel 5 of the endoscope 4,
It is possible to reduce noise coming from the equipment side such as the endoscope 4 and the light source device 3 to the observation device 2 side, in other words, noise coming onto the ultrasound diagnostic image. In addition, by covering the ultrasonic probe 6 from the probe drive unit 7 to the channel 5 hole of the endoscope 4 with the shield cable 26, it is resistant to external radiation noise coming from sources other than the observation device 2 and the devices 3 and 4. Become.

By the way, in an ultrasonic probe, the outer peripheral member of the flexible shaft that transmits the rotational driving force from the motor provided in the probe drive unit to the ultrasonic transducer is usually a double coil made of stainless steel or the like, and its potential is It is ground potential. However, due to the high resistance value of the outer circumferential member, the electric potential of the flexible shaft is not constant over its entire length, resulting in a problem that the shielding effect is reduced and external noise is easily transferred to the flexible shaft. FIG. 5 shows an ultrasonic probe that can sufficiently solve these problems.

The ultrasonic probe 30 shown in FIG. 5 has an ultrasonic transducer 31 at its tip, and the ultrasonic transducer 31 is held by a conductive holder 32. A flexible shaft 34 through which a signal cable 33 is inserted is connected to a holder 32 that holds the ultrasonic transducer 31 . The signal cable 33 has one end connected to the ultrasonic transducer 31 and the other end connected to an observation device (not shown) or the like. Further, the ultrasonic probe 30 has a Teflon sheet 3 on its outer periphery.
covered by 5. Flexible shaft 34
is a cylindrical first sheath 34a that is at ground potential, and a first
A second sheath 34b, which is also at ground potential, is disposed coaxially with the first sheath 34a leaving a certain gap 36 on the outside of the sheath 34a. The holder 32 is soldered to the first sheath 34a of the two sheaths of the flexible shaft 34. A conductive liquid 37 is sealed in a gap 36 between the first sheath 34a and the second sheath 34b. This conductive liquid 37 causes the flexible shaft 34 to
The potential is constant over the entire length, that is, the ground potential. Therefore, the shielding effect is improved, and external noise is less likely to get on the flexible shaft 34.

Generally, an image signal from an ultrasonic transducer at the tip of an ultrasonic probe is transmitted to a coaxial connector on the proximal side through a single signal cable consisting of a coaxial cable with an outer diameter of 0.9 mm.

However, the noise shielding properties of coaxial cables are poor, and for example, when used in conjunction with an endoscope for ultrasound diagnosis, noise from the endoscope is picked up, resulting in disturbances in ultrasound images. It may occur. Therefore, as shown in FIG. 6, the signal cable 40 can be constructed by twisting three coaxial cables 41 each having an outer diameter of 0.3 mm, using one of them for image signals and using the remaining two as dummies. Thereby, the noise signal obtained from one dummy can be arithmetically subtracted from the noisy image signal to cancel the noise in the image signal. Here, the outer diameter is 0.3m
The signal cable 40 shown in FIG. 6, which is made by twisting three coaxial cables 41 having a diameter of 0.9 mm, has the advantage of being stronger against bending than a signal cable made of one coaxial cable having an outer diameter of 0.9 mm. It also has the advantage that it is easier to twist than two coaxial cables 41 having an outer diameter of 0.3 mm.

[0027] In addition, one with an outer diameter of 0.9 mm and one with an outer diameter of 0.3 mm.
When comparing coaxial cables made of three strands of the same material with a diameter of 0.3 mm, there is a problem that the resistance value of the 0.3 mm coaxial cable is larger. This problem can be solved by using a material with better conductivity than the .9mm coaxial cable.

On the other hand, a flexible tube has conventionally been used for grounding the flexible tube of an endoscope. That is, in order to ground the flexible tube of the endoscope, the flexible tube, the operation section, and the ground cord are connected in an electrically conductive state. Furthermore, the flex tube is electrically connected to the tip of the endoscope that houses optical instruments such as a CCD, and serves as a ground line connecting the operating section and the tip. .

However, when performing ultrasonic diagnosis by inserting an ultrasonic miniature probe into the flexible tube of an endoscope, noise generated from the light source connected to the endoscope and the eyepiece TV is received by the ground cord. It is emitted from the flex tube, rides on the ultrasound miniature probe, and can cause noise in ultrasound images. In addition, CCD drive noise may also be transferred to the ultrasonic miniature probe through the flexible tube and similarly generate noise in the ultrasonic image. Therefore, as shown in FIG. 7, a highly shielded coaxial cable 48 is used as a ground line connecting the operating section 47 and the distal end 46 of the endoscope 45, and the flex tube 49 is connected to the operating section 47 and the distal end 46. Instead, just float it electrically. As a result, no noise is transmitted from the coaxial cable 48, so that it is possible to prevent noise from being generated in the ultrasonic image from the ultrasonic miniature probe 50. Incidentally, as a safety measure when using the electric scalpel, feedback of leakage current is performed by the coaxial cable 48.

[0030]Also, the arm for holding the probe drive unit has conventionally been made by connecting two pipes rotatably at their ends, but if a heavy object is placed on the tip of the arm,
The moment applied to the connection between the two pipes became so large that the connection alone could not support the object, causing the tip of the arm to drop. Therefore, as shown in FIG. 8, a second pipe 57 is slidably fixed in a horizontal direction to a first pipe 56 provided vertically on a carrier stand 55 of the observation device.
8, so that an object, for example, the probe drive unit 7 can be placed on the tip of the second pipe 57 in the horizontal direction. This can prevent the tip end of the arm 58 from dropping unintentionally.

On the other hand, scopes such as miniature probes have conventionally been stored in scope hangers, etc., but the scopes have outer cylinders made of sheaths, etc., and are small in diameter, so they cannot be stored in scope hangers, etc. It's embarrassing. However, these problems are solved by the probe storage box 65 shown in FIGS. 9 to 12.

That is, the probe storage box 65 has a probe storage tray 66 therein, and the storage tray 66 is formed with a storage groove 67 for storing the probe in a spiral shape. Further, a motor 69 is provided in, for example, an observation device 68 that is separate from the storage box 65, and the rotational driving force of this motor 69 is transmitted to the storage tray 66 through a drive shaft 70. That is, one end of the drive shaft 70 is hermetically guided into the observation device 68 by a seal 71 of the housing of the observation device 68 and connected to the motor 69, and the other end is guided by a seal 72 of the storage box 68. It is guided airtightly into the storage box 65, is rotatably supported by a bearing 73 provided in the storage box 65, and is fitted into a shaft fitting portion 74 formed on the storage tray 66. Therefore, when storing the probe 6 in the storage box 65, first, as shown in FIG.
0 into the shaft fitting portion 74 of the storage tray 66. Next, as shown in FIG. 9(a),
The tip 6a of the probe 6 is inserted into the storage box 65 through the storage opening 75 provided on the outer wall of the storage box 65, and the tip of the probe 6 is inserted into the storage box 65 through the tip presser 76 formed on the peripheral wall of the storage groove 67.
Insert into. Thereafter, the storage tray 66 is rotated by driving the motor 69, and as shown in FIG. 9(b),
The probe 6 is wound up and stored in the storage groove 67. In addition,
The storage opening 75 is formed in a shape that allows the connector 9 of the probe 6 to protrude from the storage box 65 and be locked therein, as shown in FIG. 9(a). Then, as shown in FIG. 10(a),
Close the storage opening 75 while sliding the storage lid 77. Note that the storage lid 77 has a connector 9 protruding from the storage box 65.
It is formed in a shape that allows it to slide while being engaged with. Moreover, when taking out the probe 6 from the storage box 65, the storage box 65 is removed from the observation device 68, and FIGS.
As shown in FIG. 3, the probe driving section 7 is connected to the connector 9 of the probe 6, and the probe is pulled out from the storage box 65. Therefore, according to the probe storage box 65 configured as described above, it is possible to easily store a small diameter scope that is difficult to store with a scope hanger or the like.

Furthermore, FIG. 14 shows a probe integrated storage box 80 that is integrally formed or assembled with the probe 6 as shown in FIG. The storage box 80 includes a storage section 83 that can store the probe 6 in a spiral shape, and a storage section 83 that can store the probe 6 in a spiral shape.
A first connector 81 and a second connector 82 connected to
has. The first connector 81 is connected to the flexible shaft 13 of the probe 6, and the second connector 82 is connected to the storage section 83. Then, as shown in FIG. 15, a storage box 80 in which the probe 6 is stored.
For example, if the first connector 81 is connected to the probe drive unit 7, the first connector 81 is connected to the first motor 84 provided in the probe drive unit 7, and the first connector 82 is connected to the second motor 8.
5, the flexible shaft 13 is rotated by the rotational drive of the first motor 84 to perform radial scanning, and the storage section 83 is rotated by the rotational drive of the second motor 85 to store the probe 6 in a spiral shape. It is now possible to do so.

[0034]

Effects of the Invention As explained above, the present invention can efficiently reduce the noise transferred from a separate device to an observation device without increasing the diameter and hardness of the ultrasound probe, thereby producing good ultrasound images. Therefore, accurate ultrasonic diagnosis can be performed.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram of an intracorporeal ultrasound diagnostic apparatus showing a first embodiment of the present invention.

FIG. 2 is a partial cross-sectional view of the ultrasound probe of FIG. 1;

FIG. 3 is a schematic configuration diagram of an intracorporeal ultrasound diagnostic apparatus showing a second embodiment of the present invention.

FIG. 4 is a sectional view showing the shielded cable of FIG. 3 and the inside of the shielded cable.

FIG. 5 is a longitudinal sectional view showing another configuration example of an ultrasound probe designed to reduce external noise.

FIG. 6 is a schematic diagram showing how three signal cables as coaxial cables are twisted to reduce external noise.

FIG. 7 is a longitudinal sectional view of an endoscope into which an ultrasound probe is inserted and which can reduce external noise.

FIG. 8 is a perspective view showing an arm that supports a probe drive unit and the like, a carrier stand on which this arm is installed, and an observation device installed on the carrier stand.

FIG. 9(a) is a schematic diagram showing how the probe is stored in a storage box that can store the probe in a spiral shape;
) when viewed from the front, (c) is A-A of (a)
It is a side sectional view along a line.

FIG. 10(a) is a schematic diagram showing how a storage box containing probes in a spiral shape is covered with a storage lid, and FIG. 10(b) is a schematic diagram showing a state where the storage box is covered with a storage lid.

11 is a schematic diagram showing how the probe in the storage box of FIG. 9 and the probe driving section are connected; FIG.

12 is a schematic diagram showing how the probe in the storage box of FIG. 9 and the probe driving section are connected; FIG.

FIG. 13 is a partial cross-sectional view showing an example of an ultrasound probe.

FIG. 14 is a schematic diagram showing how probes are stored in a storage box that can store probes in a spiral shape.

FIG. 15 is a schematic diagram showing how the storage box of FIG. 14 is connected to a probe drive unit.

FIG. 16 is a schematic diagram of an endoscope that can reduce external noise.

[Explanation of symbols]

1,25...Intrabody cavity ultrasound diagnostic device 2...Observation device 3...Light source device 4...Endoscope 6...Ultrasonic probe 7...Probe drive unit 8...Ultrasonic observation department 16...GND terminal 17...E terminal 18...Cable.

Claims (1)

[Claims] 1. An ultrasound probe inserted into a body cavity, a probe drive unit that drives the ultrasound probe, and a signal obtained by driving the ultrasound probe with the probe drive unit to generate ultrasound waves at a part of the body. In an intrabody cavity ultrasound diagnostic device that uses an observation device having an ultrasound observation unit that displays a diagnostic image together with equipment such as an electric light source that is separate from this observation device, a device connected to the ground of the observation device. An intrabody cavity ultrasound diagnostic apparatus comprising: a ground terminal; and a conduction means for connecting the ground terminal and the ground of the device to have the same potential.