The present description relates to a plasma irradiation device used in a surgical operation device, to a handpiece, and to the surgical operation device.
A technique disclosed in Patent Document 1 has been proposed for a surgical operation device which utilizes plasma. The electric surgical operation device disclosed in Patent Document 1 is configured to produce discharge from an electrode to a tissue through a continuously plasmatized inert gas, thereby incising the tissue and simultaneously causing coagulation.
Although the electric surgical operation device disclosed in Patent Document 1 is advantageous in that incision of biological tissue and hemostasis (coagulation) can be performed through use of a single device, the large amount of heat applied to a hemostasis site may result in occurrence of thermal damage, etc. at the hemostasis site.
Meanwhile, Patent Document 2 discloses a hemostasis instrument in which a thermal hemostasis device for tissue coagulation and a biochemical hemostasis device are combined. This hemostasis instrument allows selective use of thermal hemostasis performed through external or internal heating of a tissue and biochemical hemostasis performed through dielectric barrier discharge. When the biochemical hemostasis is chosen, since a non-heating stanching treatment is performed through irradiation with low-temperature plasma, hemostasis is realized while thermal damage to the tissue is suppressed. However, in the biochemical hemostasis device employed in Patent Document 2, a discharge electrode and a tissue function as a pair of electrodes, and dielectric barrier discharge occurs therebetween via a dielectric member. Namely, since the biochemical hemostasis device employs a scheme in which the biological tissue itself is used as an electrode, there is a concern that current may flow into the biological tissue.
The present invention has been accomplished so as to at least partially solve the above-described problem. It is an object of the present invention to provide a handpiece which can perform at least one of incision, ablation, and hemostasis of biological tissue using an acting member and which has a configuration for allowing hemostasis through irradiation with low-temperature plasma and for suppressing heating and energization of the biological tissue during the hemostasis through irradiation with low-temperature plasma.
A plasma irradiation device which is a first means for solution is a plasma irradiation device provided in a handpiece including an acting member which acts on biological tissue, comprising:
a gas flow channel for supplying to a distal end portion of the acting member a gas supplied externally of the handpiece; and
an electric field generation section disposed in the gas flow channel, the electric field generation section including a first electrode portion, a second electrode portion facing the first electrode portion, and a dielectric member having at least a portion which is located between the first electrode portion and the second electrode portion and is disposed on at least one of a surface of the first electrode portion and a surface of the second electrode portion, the electric field generation section generating an electric field in a space within the gas flow channel by using a potential difference between the first electrode portion and the second electrode portion, thereby producing the low-temperature plasma discharge.
The plasma irradiation device having the above-described structure can add a function of hemostasis through irradiation with low-temperature plasma to the handpiece which has the basic function of performing at least one of incision, ablation, and hemostasis of biological tissue by using an acting member. Therefore, an operator can perform both the treatments (the treatment using the above-described basic function and the stanching treatment through irradiation with low-temperature plasma) through use of the common handpiece. Since these treatments can be performed by using the common handpiece, the number of instruments used for an operation target can be reduced, whereby the burden on the operation target can be mitigated more easily. In addition, since the stanching treatment is performed by causing coagulation of blood through irradiation with low-temperature plasma, minimally invasive hemostasis is possible. Also, the gas flow channel is configured to supply the gas to a distal end portion of the acting member, and low-temperature plasma is produced within the gas flow channel. Therefore, the low-temperature plasma can be effectively supplied to the vicinity of a region where the actions provided by the above-described basic function (incising action, ablating action, or stanching action) are provided for biological tissue (the vicinity of the distal end portion of the acting member). Further, the first electrode portion and the second electrode portions are disposed in the handpiece, and an electric field based on the potential difference therebetween is produced in the space within the gas flow channel provided in the handpiece. Therefore, low-temperature plasma can be produced in the handpiece without forcedly applying voltage between the operation target and the handpiece or forcedly causing current to flow to the operation target.
The dielectric member may be configured such that the portion located between the first electrode portion and the second electrode portion is in contact with one of the surface of the first electrode portion and the surface of the second electrode portion. The plasma irradiation device may be configured such that the space within the gas flow channel is present between the first electrode portion and the second electrode portion, and the low-temperature plasma discharge is produced in the space.
This plasma irradiation device can stably generate plasma in the space within the gas flow channel present between the first electrode portion and the second electrode portion. The plasma produced as a result of the discharge can be efficiently supplied to the distal end side of the acting member through use of the flow of the gas in the gas flow channel.
The dielectric member may have a first dielectric member portion disposed on a surface of the second electrode portion on a side toward the first electrode portion and a second dielectric member portion disposed on a surface of the second electrode portion on a side opposite the surface on the side toward the first electrode portion. The second electrode portion may he an electrode whose potential oscillates such that a potential of the first electrode portion becomes the center of the potential oscillation. The second dielectric member portion may have a thickness greater than a thickness of the first dielectric member portion.
In the case where, as described above, the thickness of the second dielectric member portion disposed on the surface of the second electrode portion on the side opposite the surface on the first electrode portion side is greater than the thickness of the first dielectric member portion disposed on the surface of the second electrode portion on the first electrode portion side, even when the potential of the second electrode portion becomes high due to the oscillation of the potential, the influence of the high potential becomes unlikely to reach a region on the outer side of the second dielectric member portion (a region on the side opposite the gas flow channel). As a result, a problem caused by the potential of the second electrode portion becomes less likely to occur in the region on the outer side of the second dielectric member portion. In contrast, the influence of the potential of the second electrode portion becomes more likely to reach the gas flow channel, so that the field intensity can be increased more easily within the gas flow channel.
The acting member may have a rod-like shape, and at least a portion of the acting member may serve as the first electrode portion and serve as a ground electrode.
In the case where the acting member has a rod-like shape and serves as the first electrode portion, the size and the number of components can be reduced more easily. Also, since the acting member is the ground electrode, the potential of a portion which is brought to the close vicinity of biological tissue can be made low. Therefore, even when the acting member is brought to the vicinity of the biological tissue, supply of electricity from the acting member to the biological tissue can be suppressed.
The second electrode portion may be disposed around the first electrode portion in a continuous or intermittent annular pattern. The gas flow channel may be disposed around the first electrode portion to be located on the inner side of the second electrode portion disposed in the annular pattern.
In the case where the gas flow channel is disposed around the first electrode portion to be located on the inner side of the second electrode portion disposed in an annular pattern as described above, electric fields can be produced over the entire circumference of the first electrode portion. As a result, low-temperature plasma can be produced more efficiently in the space within the gas flow channel present around the first electrode portion.
The dielectric member may be configured such that the portion located between the first electrode portion and the second electrode portion is in contact with both the surface of the first electrode portion and the surface of the second electrode portion. The dielectric member may be configured such that at least a portion of the dielectric member forms an inner wall portion of the gas flow channel, and the low-temperature plasma discharge is produced along the inner wall portion.
This plasma irradiation device can produce low-temperature plasma discharge along the inner wall portion of the gas flow channel formed by the dielectric member and efficiently supply low-temperature plasma produced as a result of the discharge toward the distal end portion side of the acting member by utilizing the flow of the gas within the gas flow channel. Also, since the low-temperature plasma discharge can be produced in a relatively narrow region along the surfaces of the dielectric members, size reduction is easily realized.
In the above-described configuration in which low-temperature plasma discharge can be produced along the inner wall portion of the gas flow channel, the dielectric member may have a first dielectric member portion disposed on a surface of the second electrode portion on a side toward the first electrode portion and a second dielectric member portion disposed on a surface of the second electrode portion on a side opposite the surface on the side toward the first electrode portion. The second electrode portion may be an electrode whose potential oscillates such that a potential of the first electrode portion becomes the center of the potential oscillation. The second dielectric member portion may have a thickness greater than a thickness of the first dielectric member portion.
In the case where, as described above, the thickness of the second dielectric member portion disposed on the surface of the second electrode portion on the side opposite the surface on the first electrode portion side is greater than the thickness of the first dielectric member portion disposed on the surface of the second electrode portion on the first electrode portion side, even when the potential of the second electrode portion becomes high due to the oscillation of the potential, the influence of the high potential becomes unlikely to reach a region on the outer side of the second dielectric member portion (a region on the side opposite the gas flow channel). As a result, a problem caused by the potential of the second electrode portion becomes less likely to occur in the region on the outer side of the second dielectric member portion. In contrast, the influence of the potential of the second electrode portion becomes more likely to reach the gas flow channel, so that the field intensity can be increased more easily within the gas flow channel.
In the above-described configuration in which low-temperature plasma discharge can be produced along the inner wall portion of the gas flow channel, the first electrode portion may be disposed in a continuous or intermittent annular pattern. The second electrode portion may be disposed in a continuous or intermittent annular pattern around the first electrode portion disposed in the annular pattern.
Since the first electrode portion and the second electrode portion are annularly disposed as described above, a wider region for generation of low-temperature plasma discharge can be secured.
The plasma irradiation device may comprise a tubular portion which includes the acting member provided therein and extending in a predetermined direction. The acting member may have a rod-like shape, and one end portion of the acting member may serve as an acting portion acting on biological tissue.
According to this configuration, the plasma irradiation device can be configured such that the rod-shaped acting member whose one end portion serves as an acting portion (a portion acting on biological tissue) is disposed inside the tubular portion, whereby low-temperature plasma can be supplied toward the acting portion in the plasma irradiation device having such a structure.
The electric field generation section may be provided in the tubular portion to be located at a position corresponding to the one end portion of the acting member (a position corresponding to the acting portion acting on biological tissue.
Since the electric field generation section is configured to produce low-temperature plasma discharge on the one end side of the acting member (the side toward the acting portion which acts on biological tissue) as described above, the low-temperature plasma produced as a result of discharge becomes more likely to be efficiently supplied to the vicinity of the acting portion.
A handpiece which is a second means for solution comprises the above-described plasma irradiation device which is the first means for solution, and a drive section for driving the acting member. The drive section is an ultrasonic vibration section for generating ultrasonic vibration. The acting member vibrates as a result of transmission of the ultrasonic vibration generated by the ultrasonic vibration section to the acting member, thereby performing an incising action, an ablating action, or a thermocoagulation stanching action for the biological tissue.
This handpiece yields effects similar to those of the plasma irradiation device of the first means for solution. Further, this handpiece allows an operator to perform, through use of the common handpiece, incision, ablation, or hemostasis (through thermocoagulation) of biological tissue by ultrasonic vibration, as well as hemostasis through irradiation with low-temperature plasma.
A handpiece which is a third means for solution comprises the above-described plasma irradiation device which is the first means for solution, and a drive section for driving the acting member. The drive section is a high-frequency current supply section for supplying high-frequency current. As a result of the high-frequency current supplied from the high-frequency current supply section flowing through the acting member, the acting member performs an incising action, an ablating action, or a thermocoagulation stanching action for the biological tissue.
This handpiece yields effects similar to those of the plasma irradiation device of the first means for solution Further, this handpiece allows an operator to perform, through use of the common handpiece, incision, ablation, or hemostasis (through thermocoagulation) of biological tissue by high-frequency current flowing through the acting member, as well as hemostasis by irradiation with low-temperature plasma.
A handpiece which is a fourth means for solution comprises the above-described plasma irradiation device which is the first means for solution, and a displacement device for moving the acting member between a projecting position at which the acting member projects from the tubular portion and a retracted position at which the amount of projection of the acting member is smaller than that at the projecting position.
This handpiece yields effects similar to those of the plasma irradiation device of the first means for solution. Further, when necessary, he acting member can be retracted, and the stanching treatment through application of low-temperature plasma can be performed in a state in which the acting member is located at the retracted position.
Any of the above-described features which can be added to the plasma irradiation device of the first means for solution can be added to the handpieces of the second, third, and fourth means for solution
A surgical operation device which is a fifth means for solution includes the handpiece of any one of the second through fourth means for solution.
This surgical operation device yields effects similar to those of the plasma irradiation device of the first means for solution. Further, this surgical operation device yields effects similar to those of the handpiece of any one of the second through fourth means for solution.
Any of the above-described features which can be added to the plasma irradiation device of the first means for solution can be added to the surgical operation device of the fifth means for solution.
According to the present invention, a handpiece which can perform at least one of incision, ablation, and hemostasis of biological tissue using an acting member makes it possible to perform hemostasis through irradiation with low-temperature plasma and suppress heating and energization of the biological tissue at the time of hemostasis through irradiation with low-temperature plasma.
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1. Overall Structure of Surgical Operation Device
A surgical operation device 1 shown in
The controller 5 is an apparatus for providing the ultrasonic vibration section 12 with an electric signal for generation of ultrasonic vibration. The controller 5 is configured to provide the electric signal t the ultrasonic vibration section 12 through, for example, an unillustrated flexible signal cable extending between the handpiece 3 and the controller 5.
The gas supply unit 7 is an apparatus for supplying an inert gas such as helium gas or argon gas. The gas supply unit 7 supplies the inert gas to the gas flow channel 22 through, for example, an unillustrated flexible pipe extending between the handpiece 3 and the gas supply unit 7.
The power supply unit 9 is an apparatus for applying a desired voltage to a first electrode portion (an acting member 31) and second electrode portions 32 of the plasma irradiation device 20, which will be described later. Specifically, the power supply unit 9 supplies an AC voltage of a predetermined frequency between the first electrode portion (the acting member 31) and the second electrode portions 32 while maintaining the acting member 31 (the first electrode portion) at a ground potential. The power supply unit 9 may employ any of various known circuits which can produce AC voltage. Notably, in the example of
The handpiece 3 is an apparatus which is held and used by an operator who performs surgical operation. The handpiece 3 mainly includes the plasma irradiation device 20, the ultrasonic vibration section 12, a movable member displacement mechanism 60, a casing 14, etc.
The casing 14 is composed of a cylindrical first casing 14A extending in a predetermined direction and a cylindrical second casing 14B connected to one end of the first casing 14A and extending in the predetermined direction. The ultrasonic vibration section 12, etc. are accommodated in the first casing 14A, and the plasma irradiation device 20, etc. are accommodated in the second casing 14B. Notably, in
The ultrasonic vibration section 12 is configured as a known ultrasonic vibrator. When a predetermined electric signal is applied to the ultrasonic vibration section 12 by the above-described controller 5, the ultrasonic vibration section 12 operates to transmit an ultrasonic vibration to the acting member 31 having a rod-like shape. This ultrasonic vibration section 12 corresponds to one example of the drive section and drives the acting member 31 in such a manner that an action of incising, ablating, or stanching, through thermocoagulation, biological tissue occurs near a distal end of the acting member 31.
The acting member 31 is a member whose distal end portion acts on the biological tissue as a stationary blade. The acting member 31 corresponds to an example of the vibration member to which the ultrasonic vibration generated by the ultrasonic vibration section 12 is transmitted. When the ultrasonic vibration is transmitted by the ultrasonic vibration section 12, the acting member 31 operates in such a manner that an action of incising, ablating, or stanching, through thermocoagulation, biological tissue occurs near the distal end of the acting member 31. Notably, the acting member 31 will be described later in more detail.
The movable member displacement mechanism 60 is a mechanism which displaces a movable member 66 functioning as a movable blade, and a known moving mechanism is employed. This movable member displacement mechanism 60 includes the stationary grip portion 62 fixed to the first casing 14A; a movable grip portion 64 attached to be movable relative to the stationary grip portion 62; the movable member 66 which moves together with the movable grip portion 64 in an interlocked manner; and an unillustrated interlocking mechanism which is linked to the movable grip portion 64 and the movable member 66 and which moves the movable member 66 in accordance with displacement of the movable grip portion 64. In the movable member di placement mechanism 60, the rod-shaped movable member 66 is pivotable on a pivot axis near a distal end of the second casing 14B. When an operation of moving the movable grip portion 64 toward the stationary grip portion 62 is performed as shown by an alternate long and two short dashes line in
The handpiece 3 configured as described above allows an operator to perform an incising treatment an ablating treatment, and a stanching treatment for biological tissue through use of ultrasonic vibration. For example, when the biological tissue is nipped between the distal end portion of the acting member 31 functioning as a stationary blade and the movable member 66 functioning as a movable blade, a portion of the biological tissue can be cut and removed by the ultrasonic vibration applied to the acting member 31. Also, the acting member 31 to which ultrasonic vibration is applied can be brought into contact with the biological tissue so as to generate frictional heat, thereby performing hemostasis. Also, the ablation treatment can performed by nipping the biological tissue between the acting member 31 and the movable member 66 with or without application of ultrasonic vibration to the acting member 31. As described above, the handpiece 3 allows the operator to perform incision, ablation, or hemostasis (through thermocoagulation) by using ultrasonic vibration. Further, the handpiece 3 allows the operator to perform minimally invasive hemostasis through application of low-temperature plasma from the plasma irradiation device 20 which will be described later. This minimally invasive hemostasis can be performed in a state in which the biological tissue is nipped between the distal end portion of the acting member 31 functioning as a stationary blade and the movable member 66 functioning as a movable blade.
Next, the structure of the plasma irradiation device 20 will be described in detail.
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In the plasma irradiation device 20 configured as described above, the space of the gas flow channel 22 is present between the acting member 31 (the first electrode portion) and the second electrode portions 32, and the inert gas flows through the space. The power supply unit 9 applies an AC voltage having a predetermined frequency between the acting member 31 and the second electrode portions 32. This power supply unit 9 operates to maintain the acting member 31 (the first electrode portion) at the ground potential and oscillationally change the potentials of the second electrode portions 32 within a range between a potential of +A (V) and a potential of −A V). The potential of +A (V) is higher than the potential of the acting member 31 (which is the ground potential and is the center of the range) by a predetermined amount. The potential of −A (V) is lower than the potential of the acting member 31 by a predetermined amount. Notably, “A” 1s a positive value. When the AC voltage is applied, changes in electric field occur between the acting member 31 and the second electrode portions 32 in a state in which respective barriers are formed on the acting member 31 and the second electrode portions 32 by the dielectric member 40. As a result, dielectric barrier discharge is produced in the space within the gas flow channel 22 present between the acting member 31 (the first electrode portion) and the second electrode portions 32. In the gas flow channel 22, the inert gas flows toward an end portion of the gas flow channel 22 (specifically, an opening portion 52 forming an end portion of the tubular portion 50 shown in FIG. The low-temperature plasma produced as a result of the dielectric barrier discharge is discharged from the end portion of the gas flow channel 22 toward the distal end side of the acting member 31. Since the handpiece 3 has the structure as described above, the operator can irradiate a bleeding portion with the low-temperature plasma by operating the handpiece 3 such that its distal end portion (a distal end portion of the acting member 31) is directed toward the bleeding portion and by activating the plasma irradiation device 20. As a result, blood coagulation occurs, whereby a stanching treatment can be performed.
Next, a method of manufacturing the plasma irradiation device 20 will be described. Here, a method of manufacturing the wall portions (wall portions 50A, 50B, 50C, and 50D) constituting the tubular portion 50 shown in
For manufacture of the wall portions constituting the tubular portion 50, a first ceramic green sheet formation step is performed first. As shown in
After having performed the first ceramic green sheet formation step as shown in
After the unfired conductive layer formation step, a second ceramic green sheet formation step is performed. In the second ceramic green sheet formation step, a second ceramic green sheet 142B having a predetermined thickness is formed by using a ceramic material containing alumina powder as a main component, and, as shown in
Next, after performing a drying step and a debindering step in accordance with known procedures, a firing step of heating the ceramic laminate (ceramic green sheets and unfired electrodes) to a predetermined temperature (for example, about 1400° C. to 1600° C.) at which alumina and tungsten can sinter is performed. As a result of this firing step, as shown in
A plating layer 138 (for example, an Ni plating layer) is formed on the plate-shaped member 150 produced as described above such that the plating layer 138 covers the surface electrode portion 136. In this structure, the second electrode portion 32 electrically communicates with the surface electrode portion 136 through the via hole 134. Accordingly, it becomes possible to set the potential of the second electrode portion 32 through the surface electrode portion 136.
A plurality of plate-shaped members 150 (
After formation of the tubular portion 50, the acting member 31 (specifically, a rod-shaped body which includes a shaft member made of metal and machined into a predetermined shape and a dielectric member (the first-electrode-portion-side dielectric member 41) covering a portion of the shaft member) is disposed inside the tubular portion 50, and the tubular portion 50 and the acting member 31 are held such that they have a predetermined positional relation therebetween, whereby the plasma irradiation device 20 shown
Notably, in the example of
Next, the effects of the present configuration will be described.
The plasma irradiation device 20 can add a function of hemostasis through irradiation with low-temperature plasma to the handpiece 3 which has a basic function of incising or ablating biological tissue or hemostasis through thermocoagulation. Therefore, an operator can perform both the treatments (the treatment using the above-described basic function and the stanching treatment through irradiation with low-temperature plasma) through use of the common handpiece 3. Since these treatments can be performed by using the common handpiece 3, the number of instruments used for an operation target can be reduced, whereby the burden on the operation target can be mitigated more easily.
In an assumed case where the handpiece 3 is applied to, for example, endoscopic surgery, since the plasma irradiation device 20 is integrated with a device which can perform incision, ablation, or hemostasis (through thermocoagulation) by using ultrasonic vibration, the number of instruments inserted into the abdominal cavity can be reduced, whereby the burden on a patient can be reduced further.
In addition, since the stanching treatment is performed by causing coagulation of blood through irradiation with low-temperature plasma, minimally invasive hemostasis is possible.
In particular, since hemostasis through application of low-temperature plasma does not cause thermal damage, the risk of postoperative troubles can be reduced. Also, since a scar stemming from the thermal damage is unlikely to remain, there is a merit that the lesion site can be easily specified at the time of re-operation. Also, since smoke due to application of heat during the stanching treatment is not produced, a problem that the field of view is narrowed by smoke during an operation is unlikely to occur.
Also, the gas flow channel 22 is configured to supply the gas to a distal end portion of the acting member 31, and low-temperature plasma is produced within the gas flow channel 22. Therefore, the low-temperature plasma can be effectively supplied to the vicinity of a region where actions provided by the above-described basic function (incising action, ablating action, or thermocoagulation stanching action) are provided for biological tissue (the vicinity of the distal end portion of the acting member 31).
Further, the first electrode portion (the acting member 31) and the second electrode portions 32 are disposed in the handpiece 3, and an electric field based on the potential difference therebetween is produced in the space within the gas flow channel 22 provided in the handpiece 3. Therefore, low-temperature plasma can be produced in the handpiece 3 without forcedly applying voltage between the operation target and the handpiece 3 or forcedly causing current to flow to the operation target.
When the ultrasonic vibration generated at the ultrasonic vibration section 12 (the drive section) is transmitted to the acting member 31, the acting member 31 itself vibrates and provides the incising action, the ablating action, or the thermocoagulation stanching action for the biological tissue. By virtue of this configuration, the plasma irradiation device 20 allows an operator to perform, through use of the common handpiece, incision, ablation, or hemostasis (through thermocoagulation) of biological tissue by ultrasonic vibration, as well as minimally invasive hemostasis by irradiation with low-temperature plasma.
The dielectric member 40 is configured such that its portion located between the acting member 31 (the first electrode portion) and the second electrode portions 32 is in contact with only one of the surface of the acting member 31 (the first electrode portion) and the surfaces of the second electrode portions 32 (specifically, only the surfaces of the second electrode portions 32). The plasma irradiation device 20 is configured such that the space within the gas flow channel 22 is present between the acting member 31 (the first electrode portion) and the second electrode portions 32, and low-temperature plasma discharge is produced in the space. This plasma irradiation device 20 can stably generate plasma in the space within the gas flow channel 22 present between the acting member 31 (the first electrode portion) and the second electrode portions 32. The low-temperature plasma produced as a result of the discharge can be efficiently supplied to the distal end side of the acting member 31 through use of the flow of the gas produced in the gas flow channel 22.
The dielectric member 40 includes the first dielectric member portions 420 disposed on the surfaces of the second electrode portions 32 on the side toward the acting member 31 (the first electrode portion), and the second dielectric member portions 42D disposed on the surfaces of the second electrode portions 32 opposite the side toward the acting member 31 (the first electrode portion). Each of the second electrode portions 32 serves as an electrode whose potential oscillates such that the potential of the acting member 31 (the first electrode portion) (the ground potential) becomes the center of the potential oscillation. The thickness T2 of the second dielectric member portions 42D is greater than the thickness T1 of the first dielectric member portions 420. In the case where the thickness T2 of the second dielectric member portions 42D is greater than the thickness T1 of the first dielectric member portions 420 as described above, even when the potential of the second electrode portions 32 becomes high due to the oscillation of the potential, the influence of the high potential becomes unlikely to reach a region on the outer side of the second dielectric member portions 42D (a region on the side opposite the gas flow channel 22). As a result, a problem caused by the potential of the second electrode portions 32 becomes less likely to occur in the region on the outer side of the second dielectric member portions 42D (for example, on the outer side of the second casing 14B). In contrast, the influence of the potential of the second electrode portions 32 becomes more likely to reach the gas flow channel 22, so that the field intensity can be increased more easily within the gas flow channel 22.
The acting member 31 has a rod-like shape, and at least a portion of the acting member 31 serves as a first electrode portion and a ground electrode. In the case where the acting member 31 has a rod-like shape and also serves as the first electrode portion, the size and the number of components can be reduced more easily. Also, since the acting member 31 is the ground electrode, the potential of a portion which is brought to the close vicinity of biological tissue can be made low. Therefore, even when the acting member 31 is brought to the vicinity of the biological tissue, supply of electricity from the acting member 31 to the biological tissue can be suppressed. Notably, although no limitation is imposed on the potential state of the biological tissue, the biological tissue and the acting member 31 may be maintained at the same ground potential by electrically connecting the acting member 31 (which is formed as a ground electrode) and the biological tissue through an unillustrated wire. In this case, an earth wire for grounding may be electrically connected to the acting member 31 or the biological tissue so that the acting member 31 or the biological tissue are grounded.
The second electrode portions 32 are disposed around the acting member 31 (the first electrode portion) in an intermittent annular pattern. The gas flow channel 22 is disposed around the acting member 31 (the first electrode portion) to be located on the inner side of the second electrode portions 32 disposed in the annular pattern. In the case where, as described above, the gas flow channel 22 is disposed around the acting member 31 (the first electrode portion) to be located on the inner side of the annularly disposed second electrode portions 32, electric fields can be produced over the entire circumference of the acting member 31 (the first electrode portion). As a result, low-temperature plasma can be produced more efficiently in the space within the gas flow channel 22 present around the acting member 31 (the first electrode portion).
The acting member 31 is formed as a vibration member to which the ultrasonic vibration generated by the ultrasonic vibration section 12 is transmitted. The handpiece 3 is configured to provide an incising action, an ablating action, or a thermocoagulation stanching action for biological tissue by utilizing the vibration of the acting member 31 (the vibration member). In this configuration, the acting member 31 serving as the first electrode portion is also used as a vibration member which is brought into contact with biological tissue so as to provide an incising action, an ablating action, or a thermocoagulation stanching action for the biological tissue. Therefore, the number of components can be reduced further, which is advantageous for size reduction. In addition, since the vibration member (the acting member 31) which comes into contact with biological tissue can be stably maintained at the ground potential, the biological tissue is less likely to receive an electrical adverse effect.
The plasma irradiation device 20 has the tubular portion 50 which accommodates the acting member 31 and extends in a predetermined direction (the extension direction of the second casing 14B (the extension portion)). The acting member 31 is formed into a rod-like shape and its portion on one end side thereof serves as an acting portion which acts on biological tissue. By virtue of this configuration, the plasma irradiation device 20 can be configured such that the rod-shaped acting member 31 whose one end portion serves as an acting portion (a portion acting on biological tissue) is disposed inside the tubular portion 50, whereby low-temperature plasma can be supplied toward the acting portion in the plasma irradiation device 20 having such a structure. Specifically, the gas flow channel 22 is formed by an inner wall portion of the tubular portion 50 and an outer surface portion of the acting member 31 or a covering portion (the first-electrode-portion-side dielectric member 41) covering the outer surface portion. In the case where the gas flow channel 22 is formed as described above, it is possible to cause a gas to flow along the acting member 31 in the vicinity of the acting member 31. As a result, low-temperature plasma can be efficiently supplied toward the acting portion (a distal end portion of the acting member 31).
The electric field generation section 30 is provided in the tubular portion 50 to be located at a position corresponding to one end of the acting member 31 (a position corresponding to the acting portion which acts on biological tissue). Since the electric field generation section 30 is configured to produce low-temperature plasma discharge on the one end side of the acting member 31 (the side toward the acting portion which acts on biological tissue), the low-temperature plasma produced as a result of discharge becomes more likely to be efficiently supplied to the vicinity of the acting portion. Specifically, the handpiece 3 having the plasma irradiation device 20 incorporated thereinto includes the first casing 14A (the proximal portion) where the grip portion (the stationary grip portion 62 and the movable grip portion 64) is provided, and the second casing 14B (the extension portion) extending in the predetermined direction from the first casing 14A (the proximal portion). The electric field generation section 30 is provided in the second casing 14B (the extension portion) and is configured to produce low-temperature plasma discharge at position near the distal end of the second casing 14B (the extension portion). Since the electric field generation section 30 is configured as described above, the low-temperature plasma generated as a result of discharge becomes more likely to be efficiently supplied toward the distal end side of the second casing 14B (the extension portion).
Next, a second embodiment will be described.
A surgical operation device 201 to which a plasma irradiation device 220 of a second embodiment is applied is obtained by replacing the plasma irradiation device 20 of the surgical operation device 1 shown
The plasma irradiation device 220 is incorporated into the handpiece 203 and is configured as an apparatus which produces creeping discharge inside the handpiece 203. As shown in
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In present structure as well, the second electrode portions 232 are electrodes whose potential can change to be higher than the potential of the first electrode portions 231, and each of the dielectric members 240 of the plurality of wall portions 250A, 250B, 250C, and 250D, has the first dielectric member portion 241 disposed on a surface of the second electrode portion 232 on the side toward the first electrode portion 231, and the second dielectric member portion 242 disposed on the surface of the second electrode portion 232 on the side opposite the surface on the side toward the first electrode portion 231. As shown in
As shown in
In the plasma irradiation device 220 configured as described above, the inner wall of the gas flow channel 222 is formed by the dielectric members 240 at the respective wall portions 250A, 250B, 250C, and 250D of the tubular portion 250, and, at each wall portion 250A, 250B, 250C, or 250D, creeping discharge occurs in the vicinity of the inner wall surface (the boundary surface between the wall portion and the space of the gas flow channel 222). Specifically, as shown in
Next, a method of manufacturing the plasma irradiation device 220 will be described. Here, a method of manufacturing the wall portions (wall portions 250A, 250B, 250C, and 250D) constituting the tubular portion 250 shown in
For manufacture of the wall portions constituting the tubular portion 250, a first ceramic green sheet formation step is performed first. As shown in
A plurality of plate-shaped members 251 (
As described above, in the plasma irradiation device 220 of the present structure, the portions of the dielectric members 240 located between the first electrode portions 231 and the second electrode portions 232 are in contact with the surfaces of the first electrode portions 231 and the surfaces of the second electrode portions 232. At least portions of the dielectric members 240 constitute the inner wall of the gas flow channel 222, and low-temperature plasma discharge is produced along the inner wall. By virtue of this structure, it is possible to produce low-temperature plasma discharge along the inner wall surface of the gas flow, channel 222 (the surfaces of the dielectric members 240 on the side toward the gas flow channel 222) and to efficiently supply low-temperature plasma produced as a result of the discharge toward the distal end portion side of the acting member 212 by utilizing the flow of the gas within the gas flow channel 222. Also, since the low-temperature plasma discharge can be produced in a relatively narrow region along the surfaces of the dielectric members 240, size reduction is easily realized.
Also, each dielectric member 240 has the first dielectric member portion 241 disposed on the surface of the corresponding second electrode portion 232 located on the side toward the corresponding first electrode portion 241, and the second dielectric member portion 242 disposed on the surface of the corresponding second electrode portion 232 located on the side opposite the surface on the side toward the first electrode portion 231. The second electrode portion 232 serves as an electrode whose potential oscillates such that the potential of the first electrode portion 231 (the ground potential) becomes the center of the potential oscillation. The thickness T4 of the second dielectric member portion 242 is greater than the thickness T3 of the first dielectric member portion 241. In the case where the thickness T4 of the second dielectric member portion 242 is greater than the thickness T3 of the first dielectric member portion 241 as described above, even when the potential of the second electrode portions 232 becomes high due to the oscillation of the potential, the influence of the high potential becomes unlikely to reach a region on the outer side of the second dielectric member portion 242 (a region on the side opposite the gas flow channel 222). As a result, a problem caused by the potential of the second electrode portions 232 becomes less likely to occur in the region on the outer side of the second dielectric member portion 242 (for example, on the outer side of the second casing 14B). In contrast, the influence of the potential of the second electrode portion 232 becomes more likely to reach the gas flow channel 222, so that the field intensity can be increased more easily within the gas flow channel 222.
Also, the first electrode portions 231 are disposed around the acting member 212 in an intermittent annular pattern, and the second electrode portions 232 are disposed, in an intermittent annular pattern, around the first electrode portions 231 disposed in an annular pattern. Since the first electrode portions 231 and the second electrode portions 232 are annularly disposed around the acting member 212 as described above, a wider region for generation of low-temperature plasma discharge can be secured around the acting member 212.
A plasma irradiation device 220 of a third embodiment shown in
In the surgical operation device 301 to which the plasma irradiation device 220 of the third embodiment is applied, a handpiece 403 is configured such that a grip portion 314A formed as a cylindrical case is provided and the plasma irradiation device 220 (see
In the third embodiment, a controller 305 corresponding to the drive section is configured as a high-frequency-current supply section for supplying high frequency current, and the acting member 31 functions as an electrode portion through which the high frequency current supplied from the controller 305 (high-frequency-current supply section) flows. Namely, the acting member 312 can function as a known electric knife. The acting member 312 is configured to provide an incising action, an ablating action, or a thermocoagulation stanching action for biological tissue by utilizing the high frequency current flowing through the acting member 312 (the electrode portion). This plasma irradiation device 220 allows an operator to perform, through use of the common handpiece 303, incision, ablation, or hemostasis (through thermocoagulation) of biological tissue by the high frequency current flowing through the acting member 312 (the electrode portion), as well as minimally invasive hemostasis by irradiation with low-temperature plasma. Notably, in the example of
Next, a plasma irradiation device 420 of a fourth embodiment will be described.
The plasma irradiation device 420 of the fourth embodiment shown in
The plasma irradiation device 420 shown in
Next, a plasma irradiation device 520 of a fifth embodiment and a surgical operation device 501 including the plasma irradiation device 520 will be described with reference to mainly
As shown in
The surgical operation device 501 shown in
The handpiece 503 mainly includes the plasma irradiation device 520, the ultrasonic vibration section 12, a movable member displacement mechanism 560, a casing 514, etc. The ultrasonic vibration section 12, etc. are accommodated in the casing 514. The acting member 535 is a member whose distal end portion acts on the biological tissue as a stationary blade. The acting member 535 corresponds to an example of the vibration member to which the ultrasonic vibration generated by the ultrasonic vibration section 12 is transmitted. The movable member displacement mechanism 560 is a mechanism which displaces a movable member 566 functioning as a movable blade and employs a known movable mechanism. This movable member displacement mechanism 560 includes a stationary grip portion 562 fixed to the casing 514; and a movable grip portion 564 attached to be movable relative to the stationary grip portion 562. The rod-shaped movable member 566 is pivotable about a pivot axis near a distal end portion of the casing 514. When an operation of moving the movable grip portion 564 toward the stationary grip portion 562 is performed, the movable member 566 pivots in such a manner that a distal end portion of the movable member 566 moves toward a distal end portion of the acting member 535. In contrast, when an operation of separating the movable grip portion 564 from the stationary grip portion 62 is performed, the movable member 566 pivots in such a manner that the distal end portion of the movable member 566 moves away from the distal end portion of the acting member 535.
As shown in
The electric field generation section 530 operates to produce low-temperature plasma in the elongated handpiece 503 (
The dielectric member 540 constitutes a plurality of wall portions 541, 542, 543, and 544, and these wall portions 541, 542, 543, and 544 define a square gas flow channel 522. The inner wall surface of the gas flow channel 522 is formed by the wall surfaces of the wall portions 541, 542, 543, and 544. The wall portion 542 a wall portion (a wall portion formed by the dielectric member) in which the second electrode portion 532 is embedded. The wall portion 542 includes a first dielectric member portion 542A disposed on a surface of the second electrode portion 532 located on the side toward the first electrode portion 531, and a second dielectric member portion 542E disposed on a surface of the second electrode portion 532 located on the side opposite the surface on the side toward the first electrode portion 531. The thickness T2 of the second dielectric member portion 542E is greater than the thickness T1 of the first dielectric member portion 542A. The dielectric member 540 is configured such that each of portions located between the first electrode portion 531 and the second electrode portion 532 is in contact with only one of the surface of the first electrode portion 531 and the surface of the second electrode portion 532. For example, a portion 541A located between the first electrode portion 531 and the second electrode portion 532 in the wall portion 541 is in contact with only the surface of the first electrode portion 531, and a portion (a first dielectric member portion 542A) located between the first electrode portion 531 and the second electrode portion 532 in the wall portion 542 is in contact with only the surface of the second electrode portion 532. The space within the gas flow channel 522 is present between the first electrode portion 531 and the second electrode portion 532, and the electric field generation section 530 produces low-temperature plasma discharge (space discharge) in the space.
In the plasma irradiation device 520 configured as described above, an AC voltage having a predetermined frequency is applied between the first electrode portion 531 and the second electrode portion 532 by the power supply unit 9 in a state in which the inert gas supplied from the gas supply unit 7 flows through the space within the gas flow channel 522. As a result, in a state in which the dielectric member 540 forms barriers on the first electrode portion 531 and the second electrode portion 532, changes in electric fields occur between these electrodes, whereby dielectric barrier discharge occurs in the space within the gas flow channel 522. The low-temperature plasma produced as a result of the dielectric barrier discharge is discharged from one end portion of the gas flow channel 522 toward the distal end side of the acting member 535.
Notably, in the example of
Next, a sixth embodiment will be described with reference to
The plasma irradiation device 620 shown in
The present invention is not limited to the modes of the embodiments having been described with reference to the drawings, and, for example, the features of a plurality of embodiments may be combined so long as they are not contradictory to one another. Also, the following examples fall within the technical scope of the present invention.
In the first embodiment, the second electrode portions 32 are disposed in an intermittent annular pattern. However, the second electrode portions 32 may be disposed in a continuous annular pattern. For example, a second electrode portion having a square tubular shape may be embedded in a second-electrode-portion-side dielectric member having a square tubular shape. Alternatively, a second electrode portion having a circular tubular shape may be embedded in a second-electrode-portion-side dielectric member having a circular tubular shape.
In the second and sixth embodiments, the first electrode portions 231 are disposed in an intermittent annular pattern. However, the first electrode portions 231 may be disposed in a continuous annular pattern, so long as creeping discharge is produced. Also, the second electrode portions 232 are disposed in an intermittent annular pattern. However, the second electrode portions 232 may be disposed in a continuous annular pattern, so long as creeping discharge is produced.
In the first, second, fifth, and sixth embodiments, the drive section is disposed inside the casing of the handpiece. However, the drive section may be disposed outside the casing of the handpiece as in the third embodiment. In such a case as well, the drive section is considered to be part of the handpiece.
In the third embodiment or the fourth embodiment, the discharge scheme used in the first embodiment may be used.
A portion of the plasma irradiation device 20 of the first embodiment may be modified as shown in
In the example structures shown by
In the claims and specification, the expression “acting on biological tissue” means that the acting member influences the biological tissue, thereby performing at least one of incision, ablation, and hemostasis. The acting member used in the above-described embodiments is merely an example, and acting members having various structures other than the acting member used in the above-described embodiments may be employed, so long as the employed acting member influences the biological tissue, thereby performing at least one of incision, ablation, and hemostasis.
Number | Date | Country | Kind |
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2017-082709 | Apr 2017 | JP | national |
Filing Document | Filing Date | Country | Kind |
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PCT/JP2018/015589 | 4/13/2018 | WO | 00 |