JP2009000586A - Ultrasound generator and ultrasound generating system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ultrasound generator which does not prevent a guide wire from reaching an occluding position in the tip of a meandering blood vessel such as coronary arteries and enables the guide wire to penetrate into the occluding part without requiring any skillful technique. <P>SOLUTION: The ultrasound generator possesses a main body part 50, a fixing part 70 and an ultrasound generating part 60. The main body part 50 makes the alignment guide wire 20 to be inserted into the coelome to penetrate. The fixing part 70 installed in the main body part 50 can fix the guide wire 20 at a desired position. The ultrasound generating part 60 gives an ultrasound vibration to the fixed guide wire 20. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an ultrasonic generator and an ultrasonic generation system that generate ultrasonic energy for penetrating an obstruction in a body cavity with a linear ultrasonic transmission member.

  Occlusion of body cavities, especially blood vessels, can have a significant effect on patients. For example, coronary artery occlusion of the heart causes myocardial infarction. Arterial occlusion of the lower limbs causes lameness and thus gangrene of the lower limbs, and may lead to lower limb amputations.

  Various methods are known as treatment methods for such arterial occlusion. For example, a technique is known in which a balloon catheter is passed through an occlusion site, the occlusion site is expanded, and a stent is implanted if necessary. Furthermore, a method for removing the occluded site by a laser or a mechanical excision device is also known.

  However, these methods cannot be completely treated unless the catheter itself or at least a guide wire for guiding the catheter penetrates the occlusion site. In particular, when treating a chronic complete occlusion that has passed 3 months or more after the occlusion site is formed, the occlusion site is severely cured and cannot penetrate the catheter or guide wire. Therefore, penetrating the catheter or guide wire through the occlusion site is extremely important as a first step in treatment.

  In order to penetrate the occlusion site, there is a technique in which a catheter and a guide wire are combined and the occlusion site is plucked by the distal end thereof. However, this technique requires skilled skills.

  On the other hand, there is a method of penetrating a completely occluded site using energy. For example, a technique is known in which an excimer laser is oscillated to cut off the occluded portion and pass through a guide wire. However, this approach is inflexible because the catheter is made of glass fiber to pass the laser. Therefore, the catheter may not be able to reach an occluded site ahead of a tortuous blood vessel such as a coronary artery.

In addition, a method is known in which a head that vibrates with ultrasonic waves is provided at the tip of a catheter, the head is applied to the occlusion site, the occlusion site is damaged, and a guide wire is passed (see Patent Document 1). However, in this method, the guide wire and the vibration transmission wire pass through the catheter, so that the flexibility is poor and the diameter of the catheter is increased. Therefore, the catheter may not be able to reach an occluded site ahead of a tortuous blood vessel such as a coronary artery.
Japanese Patent No. 2682536

  The present invention has been made in view of the above situation, and does not prevent the guide wire from reaching a blockage site ahead of a tortuous blood vessel such as a coronary artery, and the guidewire penetrates the blockage site without skill. The present invention relates to an ultrasonic generator that makes it possible.

  An ultrasonic generator has a main-body part, a fixing | fixed part, and an ultrasonic wave generation part. A main-body part penetrates the linear ultrasonic transmission member inserted in a body cavity. The fixing portion is provided in the main body portion and can fix the ultrasonic transmission member at an arbitrary position. The ultrasonic generator applies ultrasonic vibration to the fixed ultrasonic transmission member.

  According to the ultrasonic generator, since the ultrasonic transmission member can be fixed at an arbitrary position, the ultrasonic transmission member can be fixed when it hits the occluded site regardless of the amount of the ultrasonic transmission member inserted into the body cavity. Furthermore, by applying ultrasonic vibration to the fixed ultrasonic transmission member, it is possible to transmit ultrasonic vibration from the proximal end side of the ultrasonic transmission member to the occlusion site side, and to apply a physical force to the occlusion portion. By this physical force, the occlusion site can be broken or pry open and the ultrasonic transmission member can penetrate the occlusion site. In addition, since ultrasonic vibration is only applied from the base end side of the ultrasonic transmission member, the user can easily break the occluded portion and allow the ultrasonic transmission member to penetrate even without skilled techniques.

  FIG. 1 is a schematic diagram of an ultrasonic generation system in which an ultrasonic generator is applied to a catheter.

  The ultrasound system has a catheter 10, a guide wire 20 and an ultrasound generator 30.

  The catheter 10 includes a sheath 12 that is inserted into a body cavity and a hub 14 that is not inserted into the body cavity and is disposed on the user's hand side for operation by the user.

  The sheath 12 is formed in a long and narrow shape so that it can be easily inserted into a body cavity, for example, a blood vessel. A passage for the guide wire 20 is formed in the sheath 12 so that the guide wire 20 can be inserted therethrough.

  The hub 14 is used by an operator to adjust the insertion amount of the sheath 12 and to input physiological saline or the like. The injected physiological saline or the like is supplied into the body cavity through the sheath 12.

  The guide wire 20 is inserted into the body cavity prior to the catheter 10 and guides the catheter 10 to the target position. For example, when there is an occlusion in the coronary artery of the heart, the guide wire 20 is inserted first up to the occlusion site, and then the catheter 10 is inserted along the guide wire 20.

  The ultrasonic generator 30 is formed so that the guide wire 20 can penetrate therethrough, and fixes the guide wire 20 at an arbitrary position and applies ultrasonic vibration. The ultrasonic generator is connected to the external power source 80 and generates ultrasonic vibrations by the electric power supplied from the external power source 80.

  The structure of the ultrasonic generator 30 will be described in detail.

  2 is a view showing the inside of the housing of the ultrasonic generator, FIG. 3 is a cross-sectional view of the ultrasonic generator, and FIG. 4 is a cross-sectional view taken along line A-A ′ of FIG.

  As shown in FIG. 2, the ultrasonic generator 30 includes a housing 40, a main body 50, an ultrasonic generator 60, and a fixing unit 70.

  The housing 40 is obtained by dividing a hollow cylindrical shape into two parts and fixed to each other by, for example, concave-convex fitting.

  The housing 40 is formed with ring-shaped flanges 42, 44, 46 projecting inward. The flanges 42 and 44 sandwich the fixture 52 attached to the main body 50 and the disk-shaped metal plate 48 and fix the main body 50 from the axial direction. By sandwiching the plate material 36 together with the fixture 52, the main body 50 is firmly held. The flange 46 has an inner diameter slightly smaller than the diameter of the fixture 52, and presses the fixture 52 to fix the main body 50 from the radial direction.

  The main body 50 includes a fixture 52, a first horn 54 and a second horn 56. The fixture 52 is formed of an elastic body such as rubber. The fixture 52 has an inner groove that matches a ring-shaped convex portion 541 formed on the outer periphery of the first horn 54, and is attached to the first horn 54.

  The first horn 54 and the second horn 56 are formed in a tubular shape so that the guide wire 20 can pass therethrough. A taper 561 is provided on the base end side of the second horn of the main body 50. Due to the taper 561, the guide wire 20 inserted from the tip of the ultrasonic generator 30 passes smoothly through the second horn 56 and passes out of the ultrasonic generator 30. The first horn 54 and the second horn 56 are made of an aluminum alloy that is lightweight and has high resonance characteristics, a stainless steel or titanium alloy that can withstand high amplitude, and a carbon steel that has high strength in consideration of the characteristics of the ultrasonic generator 30 described later. It is preferably used.

  As shown in FIG. 3, a tubular hollow screw 58 is provided inside the first horn 54 and the second horn 56. Screw grooves are formed on the inner surfaces of the first horn 54 and the second horn 56, and screws that are screwed into the screw grooves are formed on the outer surface of the hollow screw 58. Therefore, the first horn 54 and the second horn 56 are integrally held by the hollow screw 58. It is preferable to fix the first horn 54 and the second horn 56 and the hollow screw 58 with a screw-fixing adhesive to enhance the integrity. The hollow screw 58 is provided with a taper 581 that expands toward the tip side. By the taper 581, the guide wire 20 inserted into the tip of the ultrasonic generator 30 is smoothly guided into the hollow screw 58.

  The ultrasonic generator 60 includes a piezoelectric element 62 (ultrasonic transducer element), an electrode 63, electric wires 64 and 65, a connector 66, and an external electric wire 68. In the present embodiment, four piezoelectric elements 62 are prepared, and four electrodes 63 are alternately stacked in series. The four piezoelectric elements 62 and the four electrodes 63 are sandwiched between the first horn 54 and the second horn 56 that are firmly fastened to the hollow screw 58. The four electrodes 63 are alternately connected by a soldering bridge 67 two by two.

  The electric wires 64 and 65 are connected to the bridge 67, respectively. The electric wires 64 and 65 are connected to the connector 66, and an AC voltage is supplied from the external power source 80 via the external electric wire 68 connected to the connector 66.

  The piezoelectric element 62 expands and contracts according to the frequency of the alternating voltage, and generates ultrasonic vibrations in the axial direction of the ultrasonic generator 60. In the present embodiment, four piezoelectric elements 62 are used, but the present invention is not limited to this. The amount of displacement due to expansion and contraction of the piezoelectric element 62 increases in proportion to the number of stacked piezoelectric elements 62. Therefore, the ultrasonic generator 60 can be configured by appropriately changing the number according to the required amount of ultrasonic vibration displacement.

  The fixing part 70 has a pipe part 72 and a tightening part 74. The pipe part 72 is a tubular member through which the guide wire 20 can penetrate. The pipe portion 72 has screws 721 and 722 formed on the outer surfaces of the proximal end side and the distal end side. The screw 721 is screwed into a screw groove formed on the distal end side of the first horn 54 to fix the tube portion 72 to the first horn 54. The screw 722 is screwed into a screw groove formed on the inner surface of the tightening portion 74 to fix the tightening portion 74 to the tube portion 72. A chuck 723 is provided at a further tip than the screw 722 of the tightening portion 74. The chuck 723 is formed with a taper 724 so as to become thinner toward the tip.

  As described above, the tightening portion 74 has a thread groove that can be fitted to the screw 722 of the tube portion 72 on the inner surface. Furthermore, a taper 741 that is inclined at a steeper angle than the taper 724 of the pipe portion 72 is formed on the inner surface of the tightening portion 74. Therefore, as the tightening portion 74 is tightened to the tube portion 72, the tightening portion 74 moves to the tube portion 72 side and narrows the width of the cross grooves 761 and 762 (see FIG. 4) formed at the tip of the tube portion 72. Squeeze. As a result, the distal end hole 75 of the tube portion 72 that penetrates the guide wire 20 is reduced, and the guide wire 20 is fixed by the inner surface of the tube portion 72. When the tightening portion 74 is loosened, the tube portion 72 is released from the compression, and the tip is restored to its original shape by elasticity. Thereby, the position of the guide wire 20 can be changed again.

  Furthermore, a taper 742 that expands toward the distal end side is provided at the distal end of the tightening portion 74. When passing the guide wire 20 through the ultrasonic generator 30, the taper 742 smoothly guides the proximal end of the guide wire 20 to the distal end hole 75 of the ultrasonic generator 30.

  Both the tube portion 72 and the tightening portion 74 are preferably made of stainless steel.

(Example)
Next, the usage procedure of an ultrasonic generator is demonstrated with the specific Example of this embodiment.

  The prepared ultrasonic generator 30 is the same as that shown in FIGS. The specifications of the main parts of the ultrasonic generator 30 are as follows.

  For the piezoelectric element 62, lead zirconate titanate was used. The piezoelectric element 62 is a ferroelectric material having a perovskite crystal structure that exhibits large piezoelectricity. The dimensions of the piezoelectric element 62 were an outer diameter of 15 mm, an inner diameter of 6.3 mm, and a thickness of 2.5 mm. Four piezoelectric elements 62 were used. Four copper electrodes 63 having a thickness of 0.2 mm were used.

  The first horn 54 was made of stainless steel, and the second horn 56 was made of aluminum alloy. The hollow screw 58 made of aluminum alloy was used. These materials prevent rusting regardless of moisture during sterilization or long-term storage. The convex portion 541 formed on the first horn 54 had an outer diameter of 18 mm and a thickness of 1 mm. A fixing member 52 matching the convex portion 541 was attached, and a cylindrical housing 40 having an outer diameter of 30 mm and a length of 51 mm was used. The total length of the ultrasonic generator was 74 mm.

  The usage procedure is as follows.

  The housing 40 of the ultrasonic generator 30 was held by the user, and the distal end of the ultrasonic generator 30 was moved toward the proximal end of the guide wire 20. That is, the distal end of the tightening portion 74 is moved toward the proximal end of the guide wire 20. Then, the guide wire 20 was smoothly introduced into the ultrasonic generator 30 without being caught by the taper 742 of the tightening portion 74. Further, when the ultrasonic generator 30 is moved in the same direction, the guide wire 20 comes out from the proximal end of the ultrasonic generator 30.

  Next, the distal end of the tube portion 72 was tightened by the tightening portion 74 to fix the guide wire 20. When an alternating voltage of 21 KHz was applied from the external power supply 80, the piezoelectric element 62 vibrated. The vibration of the piezoelectric element 62 was transmitted to the entire length of the guide wire 20, and vibration was also confirmed at the tip of the guide wire 20. When the application of the AC voltage was stopped and the tightening of the tube portion 72 by the tightening portion 74 was released, the guide wire 20 could be easily removed.

  As described above, the ultrasonic generator 30 is fixed at a free position of the guide wire 20 and can transmit the ultrasonic wave to the guide wire 20. Therefore, for example, when a chronic occlusion site is formed in the coronary artery of the heart, the guide wire 20 can be passed through the occlusion site using the ultrasonic generator 30.

  In this case, the guide wire 20 and the catheter 10 are first advanced through the blood vessel to the chronic occlusion site. When the guide wire 20 hits the obstruction site and cannot proceed any further, the user inserts the ultrasonic wave into the ultrasonic generator 30 from the proximal end of the guide wire 20. As shown in FIG. 1, the ultrasonic generator 30 is moved to the vicinity of the proximal end of the catheter 10 with the guide wire 20 penetrating the ultrasonic generator 30. And the clamping part 74 of the ultrasonic generator 30 is clamp | tightened in the position, and the guide wire 20 is fixed. Then, the external power source 80 is turned on to cause the piezoelectric element 62 to generate ultrasonic vibrations. The ultrasonic vibration is transmitted to the tip of the catheter 10 through the guide wire 20 in the catheter 10. The transmitted ultrasonic vibration, as ultrasonic energy, damages the occluded site and forms a hole through which the guide wire 20 can penetrate. The guide wire 20 is passed through the hole thus formed, and the guide wire 20 is released from being fixed by the ultrasonic generator 30. Thereafter, the catheter 10 can also penetrate the chronic occlusion site along the guide wire 20 to completely treat the affected area.

  As described above, according to the ultrasonic generator 30, the guide wire 20 is used as an ultrasonic transmission member, so that the structures of the catheter 10 and the guide wire 20 are not complicated. Therefore, the flexibility of the catheter 10 and the guide wire 20 is not impaired, and the catheter 10 and the guide wire 20 can easily reach an occlusion site at the tip of a tortuous blood vessel such as a coronary artery.

  The ultrasonic generator 30 can fix the guide wire 20 at an arbitrary position. Regardless of the amount of the guide wire 20 inserted into the body cavity, the ultrasonic generator 30 is located as close to the tip of the guide wire 20 as possible outside the catheter 10 (outside the body cavity) with respect to the guide wire 20 that hits the occluded site. Can be fixed. Therefore, the attenuation of the ultrasonic energy generated by the ultrasonic generator 30 is minimized and given to the occlusion site. By this physical force, the occlusion site can be broken or pry open and the ultrasonic transmission member can penetrate the occlusion site.

  Since ultrasonic energy is only applied from the proximal end side of the guide wire 20, the user does not need a skilled technique.

  Since the ultrasonic generator 30 is independent of the catheter 10 and the guide wire 20, it can be applied at low cost without changing existing equipment.

  In addition, although the said embodiment demonstrated the example which penetrates the guide wire 20 in the completely occluded site | part of a coronary artery, it is not limited to this. Even if it is not a completely occluded site, the present invention can be applied to the case where it passes through any occluded site in a body cavity through which the guide wire 20 is difficult to pass.

  The ultrasonic generator can be used to generate physical energy for penetrating a guide wire through an obstruction site in a body cavity.

It is the schematic of the ultrasonic generation system which applied the ultrasonic generator to the catheter. It is a figure which shows the housing inside of an ultrasonic generator. It is sectional drawing of an ultrasonic generator. FIG. 4 is a cross-sectional view taken along the line A-A ′ of FIG. 3.

Explanation of symbols

10 ... catheter,
20 ... guide wire,
30. Ultrasonic generator,
40. Housing,
50 ... main body,
60 ... Ultrasonic generator,
70: fixing part,
80: External power supply.

Claims (6)

A body portion that penetrates a linear ultrasonic transmission member inserted into the body cavity;
A fixing portion provided in the main body portion and capable of fixing the ultrasonic transmission member at an arbitrary position;
An ultrasonic generator that applies ultrasonic vibration to the fixed ultrasonic transmission member;
An ultrasonic generator. The main body includes a first horn and a second horn formed in a tubular shape,
The ultrasonic generator includes an ultrasonic transducer element formed in a tubular shape,
The ultrasonic transducer element is sandwiched and fixed between the first horn and the second horn so that the hollow of the tube is continuous, and a hollow through which the ultrasonic transmission member can pass is formed. 2. The ultrasonic generator according to 1. The fixing part is
A tube portion fixed to the first horn and capable of penetrating the ultrasonic transmission member penetrating the first horn;
A tightening portion that can be screwed into a thread groove formed on the surface of the tube portion;
Including
The ultrasonic generator according to claim 2, wherein an inner surface of the tube portion fixes the ultrasonic transmission member by the tightening portion tightening the tube portion.   The ultrasonic generator according to claim 1, wherein the ultrasonic transmission member is a guide wire for guiding a catheter.   The ultrasonic generator as described in any one of Claims 1-4 by which the sterilization process is performed. A linear ultrasonic transmission member;
A catheter including a linear sheath having flexibility and capable of inserting the ultrasonic transmission member therein;
An ultrasonic generator for applying ultrasonic vibration to the ultrasonic transmission member,
The ultrasonic generator is
A main body that penetrates the ultrasonic transmission member;
A fixing portion provided in the main body portion and capable of fixing the ultrasonic transmission member at an arbitrary position;
An ultrasonic generator that applies ultrasonic vibration to the fixed ultrasonic transmission member;
Including ultrasonic generation system.

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