Patent Description:
In the related art, an ultrasonic endoscope has been used in a medical field. The ultrasonic endoscope includes an imaging element and a plurality of ultrasonic transducers that are integrally disposed at a tip portion of an insertion part to be inserted into a body cavity of a subject. Each of the ultrasonic transducers generates ultrasonic waves toward a portion to be observed in the body cavity and receives ultrasonic echoes (echo signals) reflected by the portion to be observed, and electrical signals (ultrasonic wave-detection signals) corresponding to the received ultrasonic echoes are output to an ultrasonic observation device (ultrasonic processor device). Then, after various kinds of signal processing are performed in the ultrasonic observation device, the electrical signals are displayed on a monitor or the like as an ultrasonic tomographic image.

Since the ultrasonic waves and the echo signals are significantly attenuated in the air, an ultrasonic transmission medium (for example, water, oil, or the like) needs to be interposed between the ultrasonic transducers and the portion to be observed. Thus, a stretchable bag-shaped balloon is mounted on a tip portion of the ultrasonic endoscope, and an ultrasonic transmission medium is injected into the balloon so that the balloon is inflated and is in contact with the portion to be observed. Accordingly, air is excluded from a space between the ultrasonic transducers and the portion to be observed, so that the attenuation of the ultrasonic waves and the echo signals is prevented.

A supply/discharge pipe line (supply/discharge pipe line for a balloon) is inserted into the insertion part of the ultrasonic endoscope in order to supply and discharge an ultrasonic transmission medium into and from the balloon. The supply/discharge pipe line includes a supply/discharge port (tip opening) opening to the tip portion of the insertion part, and an ultrasonic transmission medium is supplied into and discharged from the balloon through the supply/discharge port.

Further, the ultrasonic endoscope is cleaned and sterilized after endoscopy, and the supply/discharge pipe line needs to be brushed. Particularly, since liquid, residue, and the like are likely to enter the supply/discharge pipe line from the supply/discharge port in a case in which endoscopy is performed in a state in which a balloon is not mounted, brushing is necessary.

In the brushing of the supply/discharge pipe line, a cleaning brush is inserted into the supply/discharge pipe line from an operation unit side where an inlet of the supply/discharge pipe line is provided, and an operation for pushing and moving the cleaning brush toward the tip in the supply/discharge pipe line and an operation for drawing a brush portion of the cleaning brush back toward the operation unit are performed.

Since the supply/discharge port opens in a direction perpendicular to the axial direction of the insertion part in the ultrasonic endoscope in the related art, the supply/discharge pipe line provided along the axial direction of the insertion part is connected to the supply/discharge port in a state in which the supply/discharge pipe line is bent at a right angle or is bent obliquely. For this reason, when brushing is performed in the supply/discharge pipe line, the brush portion disposed at the tip of the cleaning brush cannot protrude from the supply/discharge port. Accordingly, there is a problem that liquid, residue, and the like entering the supply/discharge pipe line from the supply/discharge port cannot be sufficiently removed. Furthermore, since the supply/discharge pipe line has a very small diameter ϕ of about <NUM> and a thin cleaning brush is also used, a large bending stress is applied to the cleaning brush at a bent portion of the supply/discharge pipe line when the bending angle of the supply/discharge pipe line is increased. For this reason, there is a case in which the cleaning brush may be subjected to bending damage.

In contrast, in an ultrasonic endoscope disclosed in, for example, <CIT>, a tip surface is formed outside the profile of a tip unit-protruding portion where an ultrasonic observation unit is provided (unevenly thick portion side) and a supply/discharge port (a pipe line opening) of a supply/discharge pipe line (a pipe line for a balloon) is provided on the tip surface. According to this ultrasonic endoscope, since a brush portion of a cleaning brush may easily protrude from the supply/discharge port, liquid, residue, and the like present near the supply/discharge port can be efficiently removed by the cleaning brush. Further, since the pipe line for a balloon is connected to the pipe line opening at a gentle bending angle, bending damage to the cleaning brush can also be prevented.

<CIT> discloses an endoscope which is provided with an inserting section to be introduced into a subject to be examined. The endoscope is also provided with a tube line inserted into the inserting section, and an opening, which has a tube line leading end portion connected thereto, and which is opened, in the outer circumferential portion of the inserting section, toward the outside in the diameter direction of the inserting section, with a width larger than the inner diameter of the tube line.

However, in the ultrasonic endoscope disclosed in <CIT>, in order to ensure a space in which the supply/discharge port is disposed, the tip surface needs to be formed outside the profile of the tip unit-protruding portion where the ultrasonic observation unit is provided (unevenly thick portion side) as described above, and the outer diameter of the tip portion of the insertion part needs to be large. For this reason, it is difficult to reduce the diameter and size of the tip portion of the insertion part, which causes the physical burden on a patient to be increased. Since the tip unit-protruding portion where the ultrasonic observation unit is provided needs to be made compact in order to dispose the supply/discharge port without changing the outer diameter of the tip portion of the insertion part, a space in which the ultrasonic observation unit is provided may be caused to be not sufficient.

Further, in a structure in which the supply/discharge port is exposed to the tip surface that is formed outside the profile of the tip unit-protruding portion, the balloon sticks on the supply/discharge port and closes the supply/discharge port when an ultrasonic transmission medium present in the balloon is discharged. For this reason, there is also a problem that the ultrasonic transmission medium cannot be discharged from the balloon.

The invention has been made in consideration of the above-mentioned circumstances, and an object of the invention is to provide an ultrasonic endoscope of which a supply/discharge pipe line can be efficiently cleaned with a cleaning brush while the diameter and size of a tip portion of an insertion part to be inserted into a body cavity are reduced.

The features of the dependent patent claims relate to advantageous embodiments and extensions of the invention.

According to the invention, it is possible to efficiently clean a supply/discharge pipe line for a balloon with a cleaning brush while reducing the diameter and size of a tip portion of an insertion part to be inserted into a body cavity.

An ultrasonic endoscope according to a preferred embodiment of the invention will be described in detail below with reference to the accompanying drawings.

<FIG> is a schematic view showing the configuration of an ultrasonography system using an ultrasonic endoscope to which the invention is applied.

As shown in <FIG>, an ultrasonography system <NUM> comprises an ultrasonic endoscope <NUM> that takes an image of the inside of a body cavity of a subject; an ultrasonic processor device <NUM> that generates an ultrasound image; an endoscopic processor device <NUM> that generates an endoscopic image; a light source device <NUM> that supplies illumination light, which illuminates the inside of the body cavity, to the ultrasonic endoscope <NUM>; and a monitor <NUM> that displays the ultrasound image and the endoscopic image.

The ultrasonic endoscope <NUM> includes: an insertion part <NUM> that is to be inserted into the body cavity of a subject; an operation unit <NUM> that is connected to a base end portion of the insertion part <NUM> and is operated by an operator, such as a medical doctor or a technician; and a universal cord <NUM> of which one end is connected to the operation unit <NUM>. The other end portion of the universal cord <NUM> is provided with an ultrasonic connector <NUM> that is connected to the ultrasonic processor device <NUM>, an endoscope connector <NUM> that is connected to the endoscopic processor device <NUM>, and a light source connector <NUM> that is connected to the light source device <NUM>. The ultrasonic endoscope <NUM> is detachably connected to the ultrasonic processor device <NUM>, the endoscopic processor device <NUM>, and the light source device <NUM> through the respective connectors <NUM>, <NUM>, and <NUM>. Further, a tube <NUM> for supplying air and water and a tube <NUM> for suction are connected to the light source connector <NUM>.

The monitor <NUM> receives video signals that are generated by the ultrasonic processor device <NUM> and the endoscopic processor device <NUM> and displays the ultrasound image and the endoscopic image. In regard to the display of the ultrasound image and the endoscopic image, only one of the ultrasound image and the endoscopic image can be appropriately switched and displayed on the monitor <NUM>, or both of the images can be simultaneously displayed. A monitor for displaying the ultrasound image and a monitor for displaying the endoscopic image may be separately provided. Alternatively, the ultrasound image and the endoscopic image may be displayed on one monitor.

The operation unit <NUM> is provided with an air supply/water supply button <NUM> and a suction button <NUM>, which are arranged to be parallel, a pair of angle knobs <NUM> and <NUM>, and a treatment tool insertion opening (forceps port) <NUM>.

The insertion part <NUM> has a tip, a base end, and a longitudinal axis, and includes a tip portion (hard tip portion) <NUM>, a bendable portion <NUM>, and a soft portion <NUM> in this order from the tip side. The tip portion (hard tip portion) <NUM> is formed of a hard member. The bendable portion <NUM> is connected to a base end side of the tip portion <NUM> and can be bent. The soft portion <NUM> connects a base end side of the bendable portion <NUM> to a tip side of the operation unit <NUM>, is thin and long, and has flexibility. The bendable portion <NUM> is remotely operated so as to be bent by the rotation of the pair of angle knobs <NUM> and <NUM> of the operation unit <NUM>. Accordingly, the tip portion <NUM> can be directed in a desired direction. Further, a balloon <NUM> to be described below is detachably mounted on the tip portion <NUM>.

Here, the configuration of pipe lines of the ultrasonic endoscope <NUM> will be described. <FIG> is a view showing the configuration of pipe lines of the ultrasonic endoscope <NUM>.

As shown in <FIG>, a treatment tool channel <NUM>, an air supply/water supply pipe line <NUM>, and a balloon pipe line <NUM> of which one end communicates with the internal space of the balloon <NUM> are provided in the insertion part <NUM> and the operation unit <NUM>. The balloon pipe line <NUM> is a form of a supply/discharge pipe line for a balloon of the invention.

One end of the treatment tool channel <NUM> is connected to a treatment tool outlet <NUM> (see <FIG>) to be described below, and the other end thereof is connected to the treatment tool insertion opening <NUM> of the operation unit <NUM>. The treatment tool insertion opening <NUM> is closed by a cover (not shown) except when a treatment tool is to be inserted. Further, a suction pipe line <NUM> is branched from the treatment tool channel <NUM>, and the suction pipe line <NUM> is connected to the suction button <NUM> of the operation unit <NUM>.

One end of the air supply/water supply pipe line <NUM> is connected to an air supply/water supply nozzle <NUM> (see <FIG>) to be described below, and the other end thereof is branched into an air supply pipe line <NUM> and a water supply pipe line <NUM>. The air supply pipe line <NUM> and the water supply pipe line <NUM> are connected to the air supply/water supply button <NUM> of the operation unit <NUM>.

One end of the balloon pipe line <NUM> is connected to a supply/discharge port 70a that is provided closer to the tip than a balloon mounting portion to be described below, and the other end thereof is branched into a balloon water-supply pipe line <NUM> and a balloon drain pipe line <NUM>. The balloon water-supply pipe line <NUM> is connected to the air supply/water supply button <NUM>, and the balloon drain pipe line <NUM> is connected to the suction button <NUM>.

One end of an air supply source pipe line <NUM>, which communicates with an air supply pump <NUM>, and one end of a water supply source pipe line <NUM>, which communicates with a water supply tank <NUM>, are connected to the air supply/water supply button <NUM> in addition to the air supply pipe line <NUM>, the water supply pipe line <NUM>, and the balloon water-supply pipe line <NUM>. The air supply pump <NUM> is always operated during ultrasonic observation.

A branch pipe line <NUM> is branched from the air supply source pipe line <NUM>, and the branch pipe line <NUM> is connected to an inlet of the water supply tank <NUM> (above the liquid level). Further, the other end of the water supply source pipe line <NUM> is inserted into the water supply tank <NUM> (below the liquid level). Then, when the internal pressure of the water supply tank <NUM> is increased by the supply of air from the air supply pump <NUM> through the branch pipe line <NUM>, water present in the water supply tank <NUM> is supplied to the water supply source pipe line <NUM>.

The air supply/water supply button <NUM> is a so-called two-stage switching button. Although not shown, an air outlet, which communicates with the atmosphere, is formed at an operation cap 36a of the air supply/water supply button. When the operation cap 36a is not operated, the air supply/water supply button <NUM> allows the water supply source pipe line <NUM> to be closed and allows the air supply source pipe line <NUM> to communicate with the air outlet of the operation cap 36a. Accordingly, air, which is supplied from the air supply source pipe line <NUM>, leaks from the air outlet of the air supply/water supply button <NUM>. Then, when the air outlet is closed in this state, the air supply source pipe line <NUM> and the air supply pipe line <NUM> communicate with each other in a state in which the water supply source pipe line <NUM> continues to be closed. Accordingly, air is supplied to the air supply pipe line <NUM> and is ejected to the outside from the air supply/water supply nozzle <NUM>.

Furthermore, when the operation cap 36a is halfway push-operated, the air supply/water supply button <NUM> allows the air supply source pipe line <NUM> to be closed and allows the water supply source pipe line <NUM> to communicate with only the water supply pipe line <NUM>. Accordingly, water supplied from the water supply source pipe line <NUM> is ejected from the air supply/water supply nozzle <NUM> through the water supply pipe line <NUM> and the like. Then, when the operation cap 36a is fully push-operated, the air supply/water supply button <NUM> allows the water supply source pipe line <NUM> to communicate with only the balloon water-supply pipe line <NUM> in a state in which the air supply source pipe line <NUM> continues to be closed. Accordingly, water, which is supplied from the water supply source pipe line <NUM>, is supplied into the balloon <NUM> through the balloon water-supply pipe line <NUM> and the like.

The other end of a suction source pipe line <NUM> of which one end communicates with a suction pump <NUM> is connected to the suction button <NUM> in addition to the suction pipe line <NUM> and the balloon drain pipe line <NUM>. The suction pump <NUM> is also always operated during ultrasonic observation. The suction button <NUM> is a two-stage switching button like the air supply/water supply button <NUM>.

When an operation cap 38a of the suction button <NUM> is not operated, the suction button <NUM> allows the suction source pipe line <NUM> to communicate with the outside (the atmosphere). The reason for this is that a load applied to the suction pump <NUM> is increased unless the suction source pipe line <NUM> communicates with the atmosphere since the suction pump <NUM> is always operated. When the suction source pipe line <NUM> is allowed to communicate with the atmosphere, an increase of the load of the suction pump <NUM> is suppressed.

Further, when the operation cap 38a is halfway push-operated, the suction button <NUM> allows the suction source pipe line <NUM> to communicate with only the suction pipe line <NUM>. Accordingly, a negative pressure-suction force of the suction pipe line <NUM> and the treatment tool channel <NUM> is increased, and various materials to be sucked are sucked from the treatment tool outlet <NUM> (see <FIG>). Then, when the operation cap 38a is fully push-operated, the suction button <NUM> allows the suction source pipe line <NUM> to communicate with only the balloon drain pipe line <NUM>. Accordingly, a negative pressure-suction force in the balloon drain pipe line <NUM> and the balloon pipe line <NUM> is increased, and water present in the balloon <NUM> is drained.

Next, the structure of the tip portion <NUM> of the ultrasonic endoscope <NUM> will be described in detail. <FIG> is a perspective view of the tip portion <NUM>, <FIG> is a side view of the tip portion <NUM>, and <FIG> is a plan view (a partial sectional view) of the tip portion <NUM>.

As shown in <FIG>, an ultrasonic observation unit <NUM> that acquires an ultrasound image and the endoscopic observation unit <NUM> that acquires an endoscopic image are provided at the tip portion <NUM> of the ultrasonic endoscope <NUM>.

The ultrasonic observation unit <NUM> comprises an ultrasonic transducer <NUM> that includes a plurality of ultrasonic vibrators. The respective ultrasonic vibrators of the ultrasonic transducer <NUM> are arranged at regular intervals in the shape of a convex curve along the axial direction of the tip portion <NUM> (a direction of the longitudinal axis of the insertion part <NUM>), and are adapted to be sequentially driven on the basis of drive signals that are input from the ultrasonic processor device <NUM>. Accordingly, convex electronic scanning is performed over a scanning range shown in <FIG> by W. When the respective ultrasonic vibrators are driven, the ultrasonic vibrators sequentially generate ultrasonic waves toward a portion to be observed, receive ultrasonic echoes (echo signals) reflected by the portion to be observed, and output electrical signals (ultrasonic wave-detection signals), which correspond to the received ultrasonic echoes, to the ultrasonic processor device <NUM>. Then, after various kinds of signal processing are performed in the ultrasonic processor device <NUM>, the electrical signals are displayed on the monitor <NUM> as the ultrasound image.

A bag-shaped balloon <NUM>, which covers and wraps the ultrasonic transducer <NUM>, is mounted on the tip portion <NUM> in order to prevent the attenuation of the ultrasonic waves and the ultrasonic echoes (echo signals) (see <FIG> and <FIG>). The balloon <NUM> is made of a stretchable elastic material, and a stretchable locking ring <NUM> is formed at an open end of the balloon <NUM>. A locking groove <NUM>, which forms a balloon mounting portion, is provided at the tip portion <NUM>. The locking groove <NUM> is formed of an annular groove portion that is formed over the entire circumference (outer periphery) of the tip portion <NUM> in a circumferential direction having a center on the axis. The locking ring <NUM> is fitted to the locking groove <NUM>, so that the balloon <NUM> is detachably mounted on the tip portion <NUM>.

The balloon <NUM> is inserted into the body cavity in a state in which the balloon <NUM> contracts so as to come into close contact with the outer wall surface of the tip portion <NUM>. Then, when an operator generates ultrasonic waves toward the portion to be observed from the respective ultrasonic vibrators of the ultrasonic transducer <NUM>, the operator supplies water, which is present in the water supply tank <NUM>, into the balloon <NUM> through the balloon pipe line <NUM>, the balloon water-supply pipe line <NUM>, and the like by fully push-operating the operation cap 36a of the air supply/water supply button <NUM> and inflates the balloon <NUM> until the balloon <NUM> comes into contact with the inner wall of the body cavity. Accordingly, since a space between the portion to be observed and the ultrasonic transducer <NUM> is filled with water that is an ultrasonic transmission medium, the balloon <NUM> improves the adhesiveness of the tip portion <NUM> to the inner wall of the body cavity and prevents the ultrasonic waves, which are generated from the respective ultrasonic vibrators of the ultrasonic transducer <NUM>, and the ultrasonic echoes from being attenuated by air. Further, when an operator draws the insertion part <NUM> to the outside from the body cavity, the operator discharges water, which is present in the balloon <NUM>, through the balloon pipe line <NUM>, the balloon drain pipe line <NUM>, and the like by fully push-operating the operation cap 38a of the suction button <NUM> and allows the balloon <NUM> to contract so that the balloon <NUM> comes into close contact with the outer wall surface of the tip portion <NUM> as when the operator inserts the insertion part <NUM> into the body cavity. For example, latex rubber is used for the balloon <NUM>. Further, it is preferable that the ultrasonic transmission medium supplied into the balloon <NUM> is deaerated water from which dissolved gas has been removed.

The balloon pipe line <NUM> as the supply/discharge pipe line for a balloon extends in the insertion part <NUM> as described above, and a tip-side opening surface <NUM>, which has components normal to the direction of the longitudinal axis of the insertion part <NUM> (the axial direction of the tip portion <NUM>), is provided at the tip of the balloon pipe line <NUM>. The tip-side opening surface <NUM> is provided closer to the tip than the locking groove <NUM> that forms the balloon mounting portion, and includes a supply/discharge port 70a that is opened at one end (tip) of the balloon pipe line <NUM>.

A housing member (exterior member) <NUM>, which holds the ultrasonic transducer <NUM>, is provided with a groove portion <NUM> (having a notched shape) that is formed by notching a part of the outer wall of the housing member. The groove portion <NUM> is formed toward the tip from the tip-side opening surface <NUM> as a starting point, and is formed so that at least a part of the groove portion <NUM> overlaps the ultrasonic transducer <NUM> in the direction of the longitudinal axis of the insertion part <NUM>.

A structure in which the groove portion <NUM> is provided at a left side wall portion 72a of a pair of side wall portions 72a and 72b, which face each other with the ultrasonic transducer <NUM> interposed therebetween, of an outer wall portion of the housing member <NUM> when the tip portion <NUM> is viewed from the tip side has been described in the embodiment shown in <FIG>. However, the invention is not limited thereto, and the groove portion <NUM> may be provided at a right side wall portion 72b or a bottom wall portion 72c from which these side wall portions 72a and 72b are erected, as described below.

Here, the structure of the groove portion <NUM> will be described in more detail. The groove portion <NUM>, which is formed toward the tip from the tip-side opening surface <NUM> as a starting point, extends to the near side (the base end side) of a tip surface of the tip portion <NUM> as shown in <FIG>. The groove portion <NUM> includes a straight groove 74a and an inclined groove 74b in this order from the base end side (a side where the tip-side opening surface <NUM> is formed).

The straight groove 74a extends from the tip-side opening surface <NUM> in the direction of the longitudinal axis of the insertion part <NUM>, and includes a bottom surface parallel to the direction of the longitudinal axis of the insertion part <NUM>. The straight groove 74a does not bend a brush portion, which is provided at the tip of a cleaning brush led out from the supply/discharge port 70a of the tip-side opening surface <NUM>, and guides the brush portion in the axial direction of the balloon pipe line <NUM>. It is preferable that the length L (see <FIG>) of the straight groove 74a is <NUM> or more, and the length L is <NUM> in this embodiment. If the length L is set to this length, it is possible to allow the brush portion of the cleaning brush to protrude from the supply/discharge port 70a without applying excessive stress to the brush portion of the cleaning brush.

The inclined groove 74b extends from the straight groove 74a so as to be inclined with respect to the direction of the longitudinal axis of the insertion part <NUM>, and the depth of the groove is gradually reduced toward the tip. That is, the inclined groove 74b includes a bottom surface that is formed so as to be inclined with respect to the normal direction of the tip-side opening surface <NUM> (the opening direction of the supply/discharge port 70a). Accordingly, when the brush portion of the cleaning brush, which protrudes from the supply/discharge port 70a, is further pushed and moved toward the tip, the brush portion of the cleaning brush is guided in a direction in which the brush portion is separated from the ultrasonic transducer <NUM> and is in a state in which the brush portion is drawn to the outside (the lateral side) from the outer wall surface of the housing member <NUM>. Therefore, the brush portion of the cleaning brush can be easily washed with a hand. When an inclination angle α (see <FIG>) of the inclined groove 74b is too large, excessive stress is applied to the brush portion of the cleaning brush. Accordingly, it is preferable that the inclination angle α is at least <NUM>° or less, and the inclination angle α is <NUM>° in this embodiment.

Particularly, in this embodiment, the groove portion <NUM> (having a notched shape) is formed by notching a part of the outer wall of the housing member <NUM> arranged to be parallel to the ultrasonic transducer <NUM>, that is, the groove portion <NUM> is formed so that at least a part of the groove portion <NUM> overlaps the ultrasonic transducer <NUM> in the direction of the longitudinal axis of the insertion part <NUM>. Accordingly, it is possible to sufficiently ensure the length of the groove portion <NUM> (the length of the groove portion <NUM> in the direction of the longitudinal axis of the insertion part <NUM>) without increasing the size of the tip portion <NUM> in the axial direction, and to make the inclination angle α of the inclined groove 74b be gentler. Therefore, since excessive stress is not applied to the brush portion of the cleaning brush that is guided to the lateral side of the housing member <NUM> by the inclined groove 74b, it is possible to prevent a bending damage to cleaning brush.

The endoscopic observation unit <NUM> includes an observation portion <NUM> and an illumination portion <NUM>, and the observation portion <NUM> and the illumination portion <NUM> are disposed on an inclined surface portion <NUM> that is formed on the tip portion <NUM> toward the base end from the locking groove <NUM> so as to be inclined with respect to the axial direction of the tip portion <NUM>.

The observation portion <NUM> includes an observation window <NUM>; and an objective lens of an observation optical system, and an imaging element, such as a Charge Coupled Device (CCD) or a Complementary Metal Oxide Semiconductor (CMOS), which is disposed at an image formation position of the objective lens, are provided in the rear of the observation window <NUM>. A signal cable (not shown) is connected to a board that supports the imaging element. The signal cable is inserted into the insertion part <NUM> and the universal cord <NUM>, extends up to the endoscope connector <NUM>, and is connected to the endoscopic processor device <NUM>. An observation image, which is received from the observation window <NUM>, is formed on the light-receiving surface of the imaging element and is converted to an electrical signal (an imaging signal), and the electrical signal is output to the endoscopic processor device <NUM> through the signal cable and is converted to a video signal. Then, the video signal is output to the monitor <NUM> connected to the endoscopic processor device <NUM>, so that an endoscopic image is displayed on a screen of the monitor <NUM>.

The illumination portion <NUM> includes illumination windows <NUM> and <NUM>, and a light-emitting end of a light guide <NUM> (see <FIG>) is disposed in the rear of the illumination windows <NUM> and <NUM>. The light guide <NUM> is inserted into the insertion part <NUM> and the universal cord <NUM> and an incident end of the light guide <NUM> is disposed in the light source connector <NUM>. Accordingly, the light source connector <NUM> is connected to the light source device <NUM>, so that illumination light emitted from the light source device <NUM> is transmitted to the illumination windows <NUM> and <NUM> through the light guide and is emitted forward from the illumination windows <NUM> and <NUM>.

The air supply/water supply nozzle <NUM> is provided near the observation window <NUM> on the inclined surface portion <NUM> of the tip portion <NUM> in addition to the observation window <NUM> and the illumination windows <NUM> and <NUM>. The air supply/water supply nozzle <NUM> ejects water or air to remove foreign materials and the like adhered to the surface of the observation window <NUM>.

Further, the tip portion <NUM> is provided with a treatment tool outlet <NUM>. The treatment tool outlet <NUM> is connected to the treatment tool channel <NUM> (see <FIG>) inserted into the insertion part <NUM>, and a treatment tool, which is inserted into the treatment tool insertion opening <NUM>, is introduced into the body cavity from the treatment tool outlet <NUM> through the treatment tool channel <NUM>. The treatment tool outlet <NUM> is positioned closer to the base end than the locking groove <NUM>, but may be provided close to the ultrasonic transducer <NUM> so that the movement of the treatment tool introduced into the body cavity from the treatment tool outlet <NUM> can be confirmed by an ultrasound image.

An elevator <NUM> for making the lead-out direction of the treatment tool, which is introduced into the body cavity from the treatment tool outlet <NUM>, be variable is provided in the treatment tool outlet <NUM>. A wire (not shown) is mounted on the elevator <NUM>, and the elevating angle of the elevator <NUM> is changed by a pushing/drawing operation that is performed by the operation of an elevating lever (not shown) of the operation unit <NUM>. Accordingly, the treatment tool is led out in a desired direction.

In the ultrasonic endoscope <NUM> having the above-mentioned structure, the brushing of the balloon pipe line <NUM> is performed as follows after the end of endoscopy. <FIG> is a view showing a state in which the balloon pipe line <NUM> is brushed by using the cleaning brush. As shown in <FIG>, a cleaning brush <NUM> includes a brush insertion part <NUM> and a brush portion <NUM> that is disposed at the tip portion of the brush insertion part <NUM>.

First, after the balloon <NUM> is removed from the tip portion <NUM> of the insertion part <NUM>, the cleaning brush <NUM> is inserted from the suction button <NUM> side that is an inlet of the balloon pipe line <NUM>. Then, while the cleaning brush <NUM> inserted into the balloon drain pipe line <NUM> of the balloon pipe line <NUM> is moved forward and backward, the cleaning brush <NUM> is pushed and moved toward the tip and the brush portion <NUM> of the cleaning brush <NUM> is allowed to protrude from the supply/discharge port 70a that is an outlet of the balloon pipe line <NUM>. The cleaning brush <NUM> may be inserted from the air supply/water supply button <NUM> side.

Then, when the brush portion <NUM> of the cleaning brush <NUM> is further pushed and moved, the brush portion <NUM> of the cleaning brush <NUM> is offset in a direction in which the brush portion <NUM> is separated from the axis of the tip portion <NUM> by the inclined groove 74b after the brush portion <NUM> of the cleaning brush <NUM> is guided in the same direction as the direction of the longitudinal axis of the insertion part <NUM> (that is, the axial direction of the balloon pipe line <NUM>) by the straight groove 74a.

In this case, since the groove portion <NUM> (having a notched shape) is formed by notching a part of the outer wall of the housing member <NUM> arranged to be parallel to the ultrasonic transducer <NUM> in this embodiment as described above, it is possible to sufficiently ensure the length of the groove portion <NUM> (the length of the groove portion <NUM> in the axial direction of the tip portion <NUM>) without increasing the size of the tip portion <NUM> and to make the inclination angle α (see <FIG>) of the inclined groove 74b be gentler. For this reason, since excessive stress is not applied to the brush portion <NUM>, it is possible to prevent a bending damage to the cleaning brush <NUM>. Accordingly, it is possible to easily draw the brush portion <NUM> of the cleaning brush <NUM> to the lateral side of the tip portion <NUM>. Therefore, the brush portion <NUM> can be easily washed with a hand.

Further, when the brush portion <NUM> of the cleaning brush <NUM> is washed with a hand, a user determines the degree of contamination of the brush portion <NUM>. In a case in which it is determined that the brushing of the balloon pipe line <NUM> is further needed, the user removes the cleaning brush <NUM> from the suction button <NUM> side, washes the brush portion <NUM> with a hand again, and determines the degree of contamination of the brush portion <NUM> after the user performs the brushing of the balloon pipe line <NUM> while performing an operation for drawing the cleaning brush <NUM> back. Then, in a case in which it is determined that the brushing of the balloon pipe line <NUM> is further needed, the user inserts the cleaning brush <NUM> from the suction button <NUM> side and repeatedly performs the same processing as described above.

In a case in which the brushing of the balloon pipe line <NUM> is performed as described above and a fact that the balloon pipe line <NUM> is in a clean state is determined from the degree of contamination of the brush portion <NUM> of the cleaning brush <NUM>, the brushing ends.

As described above, according to this embodiment, the tip-side opening surface <NUM> of the balloon pipe line <NUM>, which forms the supply/discharge pipe line for a balloon, is provided closer to the tip than the locking groove <NUM> that is the balloon mounting portion, includes components in the direction of the longitudinal axis of the insertion part <NUM>, and is provided with the groove portion <NUM>, which is formed toward the tip from the tip-side opening surface <NUM> as a starting point and of which at least a part overlaps the ultrasonic transducer <NUM> in the direction of the longitudinal axis. Accordingly, it is possible to provide the groove portion <NUM> without increasing the size of the tip portion <NUM> in the direction of the longitudinal axis of the insertion part <NUM>, and to sufficiently ensure the length of the groove portion <NUM>. Therefore, since it is possible to allow the brush portion of the cleaning brush to protrude from the supply/discharge port 70a without applying excessive bending stress to the cleaning brush inserted into the balloon pipe line <NUM>, it is possible to easily remove liquid, residue, and the like adhered to the vicinity of the supply/discharge port 70a. As a result, it is possible to efficiently perform the brushing of the balloon pipe line <NUM> while reducing the size and diameter of the tip portion <NUM> of the insertion part <NUM>.

In this embodiment, as shown in <FIG>, the groove portion <NUM> is formed at a position, which is closer to the base end than the tip surface 50a of the tip portion <NUM>, so as to converge. However, the invention is not limited thereto, and the groove portion <NUM> may be formed so as to extend up to the tip surface 50a of the tip portion <NUM> as shown in, for example, <FIG>. According to a structure that includes a groove portion <NUM> opened to the tip surface 50a, since the length of the groove portion <NUM> is longer than that of the structure shown in <FIG>, it is possible to make the inclination angle α (see <FIG>) of the inclined groove 74b be gentler. Accordingly, it is possible to more effectively prevent a bending damage to the cleaning brush. It is preferable that the inclination angle α of the inclined groove 74b is in the range of <NUM>° to <NUM>°, and the inclination angle α of the inclined groove 74b is set to, for example, <NUM>°.

Further, since the groove portion <NUM> is opened to the tip surface 50a of the tip portion <NUM>, an effect of allowing the balloon <NUM> to reliably contract is also obtained even if the balloon <NUM> sticks on the side surface of the tip portion <NUM> when an ultrasonic transmission medium present in the balloon <NUM> is discharged.

According to the structure in which the groove portion <NUM> is formed at a position closer to the base end than the tip surface 50a of the tip portion <NUM> so as to converge as shown in <FIG>, it is possible to smoothly machine the tip surface 50a of the tip portion <NUM>. Accordingly, it is possible to improve the insertability of the insertion part <NUM> of the ultrasonic endoscope <NUM> into the body cavity.

Furthermore, it is preferable that the base end side of the groove portion <NUM> extends toward the base end beyond the tip-side opening surface and the depth of the groove is reduced toward the base end as shown in <FIG> enlarging the vicinity of the supply/discharge port 70a in <FIG>. It is preferable that an inclination angle β of a base end-side inclined surface <NUM> of the groove portion <NUM> (the inclination angle of the base end-side inclined surface <NUM> with respect to a direction perpendicular to the direction of the longitudinal axis of the insertion part <NUM>) is in the range of <NUM>° to <NUM>°, and the inclination angle β is, for example, <NUM>°. If the groove portion <NUM> has a shape extending outward toward the base end in this way, it is possible to easily scrape off contaminations that are present near the supply/discharge port 70a when the groove portion <NUM> is brushed with a brush <NUM> for a groove portion.

Moreover, the structure in which the groove portion <NUM> is provided at the left side wall portion 72a of the pair of side wall portions 72a and 72b, which face each other with the ultrasonic transducer <NUM> interposed therebetween, of the outer wall portion of the housing member <NUM> when the tip portion <NUM> is viewed from the tip side has been described in this embodiment as shown in <FIG>. However, the groove portion <NUM> may be provided at another outer wall portion that is arranged to be parallel to the ultrasonic transducer <NUM>. For example, as shown in <FIG>, the groove portion <NUM> may be provided at the right side wall portion 72b when the tip portion <NUM> is viewed from the tip side. Further, as shown in <FIG>, the groove portion <NUM> may be provided at a bottom wall portion 72c from which the left and right side wall portions 72a and 72b are erected.

According to the structure that comprises the groove portion <NUM> (having a notched shape) formed by notching a part of the outer wall of the housing member arranged to be parallel to the ultrasonic transducer <NUM> in this way, it is possible to reduce the size and diameter of the tip portion <NUM> without increasing the outer diameter of the tip portion <NUM>. Particularly, since the groove portion <NUM> is formed so that at least a part of the groove portion <NUM> overlaps the ultrasonic transducer <NUM> in the direction of the longitudinal axis of the insertion part <NUM>, it is possible to significantly reduce the size of the tip portion <NUM> in the direction of the longitudinal axis of the insertion part <NUM> in comparison with a structure in which the groove portion <NUM> does not overlap the ultrasonic transducer <NUM>.

As shown in <FIG>, the housing member <NUM> where the groove portion <NUM> and the supply/discharge port 70a are formed does not need to be formed of a single member and may be formed of a plurality of members. For example, the housing member <NUM> may include a tip-side housing member that holds the ultrasonic transducer <NUM> and a base end-side housing member that is connected to the locking groove <NUM>, and a base end side of the groove portion <NUM> and the supply/discharge port 70a may be formed at the base end-side housing member.

Claim 1:
An ultrasonic endoscope (<NUM>) comprising:
an insertion part (<NUM>) that includes a tip portion (<NUM>), a base end portion, and a longitudinal axis;
an ultrasonic transducer (<NUM>);
a balloon mounting portion (<NUM>) on which a balloon configured to wrap the ultrasonic transducer (<NUM>) is detachably mounted;
a housing member (<NUM>) which is configured to hold the ultrasonic transducer (<NUM>) and is disposed on the tip portion (<NUM>) of the insertion part (<NUM>) via the balloon mounting portion (<NUM>);
a supply/discharge pipe line (<NUM>) for the balloon (<NUM>), that extends in the insertion part (<NUM>);
at least one groove portion (<NUM>) a part of which is formed on a surface of the housing member (<NUM>), the at least one groove portion (<NUM>) extending from its base end, toward a distal direction along the longitudinal axis; and
a tip-side opening surface (<NUM>) of the supply/discharge pipe line (<NUM>) for the balloon (<NUM>);
wherein the groove portion (<NUM>) is formed toward the tip from the tip-side opening surface (<NUM>) as a starting point corresponding to the base end.