JP2008253304A - Medical guide wire - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a medical guide wire capable of being easily inserted into an occluded blood vessel or a strongly narrowed or meandering blood vessel, quickly and surely removing a thrombus inside a narrow blood vessel such as a cerebral blood vessel, and surely preventing the damage of the blood vessel. <P>SOLUTION: The medical guide wire 10 comprises: an ultrasonic vibrating body 14 disposed to a guide wire main body 12 and capable of generating ultrasonic waves to the outside; and a power supplier 16 for making the ultrasonic vibrating body 14 ultrasonically vibrate, whereby crashing and fusing the thrombus inside the blood vessel by ultrasonic waves. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a medical guide wire that crushes and melts a thrombus formed in a blood vessel using ultrasonic waves.

  Fatal diseases such as acute myocardial infarction, cerebral infarction, pulmonary artery thromboembolism, superior intestinal vascular thromboembolism, acute peripheral artery occlusion, etc. are mainly caused by occlusion of the artery due to thrombus formed in the blood vessel Therefore, it is necessary to remove the thrombus as soon as possible to recirculate the blood vessel.

  Conventionally, as a technique for removing such a thrombus, for example, a method of dissolving a thrombus by systemic administration of a thrombus dissolving agent, or a thrombus dissolving agent is directly applied to a local thrombus using a catheter to dissolve the thrombus. Methods and the like are widely known. However, since the former method is a method in which a large amount of thrombolytic agent is administered intravenously systemically, the procedure is simple, but a large amount of thrombolytic agent is required, and complications such as cerebral hemorrhage and gastrointestinal bleeding are caused. High risk of causing. In particular, since thrombolysis with a thrombolytic agent is an enzymatic reaction, it takes time and has a drawback of lacking immediate effectiveness. The latter method is the most popular method at present, but requires a thrombolytic agent, and is complicated and time consuming, requiring skill.

  As a surgical technique, a method of pressing a thrombus with a balun or a stent catheter, a method of removing a thrombus with a thrombus suction catheter, and the like are known. However, in the former, since it is necessary to spread the blood vessel with balun etc., there is a risk of dissociation of the blood vessel wall and there is a risk of damaging the vascular endothelium. May end up. Both are effective for thick blood vessels, but when the stenosis or meandering of the blood vessels is strong, it is difficult to reach the balun to the local area and cannot be used for thin blood vessels such as cerebral arteries.

On the other hand, a catheter with an ultrasonic generator at the tip is inserted into the blood vessel and advanced to the position where the thrombus exists, and the ultrasonic generator is driven from the external drive unit via the catheter body to generate ultrasonic waves. And a method of removing the thrombus by vibrating and destroying the thrombus by the ultrasonic vibration (see, for example, Patent Document 1), or by positioning a catheter provided with an ultrasonic resonator at the distal end near the affected area, A method of removing a thrombus by causing ultrasonic waves to propagate through a tissue percutaneously from a transmitter to resonate the ultrasonic resonator (for example, see Patent Document 2) has been proposed.
JP 2005-95410 A Japanese Unexamined Patent Publication No. 6-343641

  However, in any of the above methods, since the tip of the catheter is vibrated by ultrasonic waves, there is a possibility that the catheter jumps and damages the blood vessel wall, and the thrombus cannot be vibrated in the vertical direction. . In addition, there is a limit to reducing the diameter of the hollow catheter, and it is difficult to insert the catheter into a blocked blood vessel or a blood vessel with a strong stenosis or meandering. Furthermore, the latter method has a drawback that ultrasonic waves from an external ultrasonic generator are blocked by the skull and cannot be used for thrombus in the cerebral blood vessel.

  The present invention has been made to solve such problems, and can be easily inserted into a blocked blood vessel or a blood vessel with strong stenosis or meandering. It is another object of the present invention to provide a medical guide wire that can be reliably removed and that can reliably prevent damage to blood vessels.

  The above object is achieved by the following medical guide wire of the present invention.

  (1) The present invention is configured to include an ultrasonic wave generation unit that is disposed on the guide wire body and can generate ultrasonic waves outside, and a drive unit that ultrasonically vibrates the ultrasonic wave generation unit. A medical guide wire, wherein a thrombus in a blood vessel is crushed and melted by the ultrasonic wave.

  (2) The medical guide wire according to (1), wherein the frequency band of ultrasonic waves that can be generated from the ultrasonic wave generator is 35 kHz to 95 kHz.

  (3) The medical guide wire according to (1), wherein the frequency band of ultrasonic waves that can be generated from the ultrasonic wave generator is 50 kHz to 70 kHz.

  (4) Moreover, the present invention is the medical guide wire according to any one of (1) to (3), wherein the output of the drive unit is 9 W to 50 W.

  (5) Moreover, the present invention is the medical guide wire according to any one of (1) to (3), wherein the output of the driving unit is 15 W to 35 W.

  (6) In the present invention, any one of (1) to (5) is characterized in that the ultrasonic wave generator is disposed at a predetermined interval from the tip of the guide wire body. 2. A medical guide wire according to item 1.

  (7) In the present invention, any one of (1) to (6) is characterized in that the ultrasonic wave generation unit is an ultrasonic vibration body capable of ultrasonic vibration by being deformed. 2. A medical guide wire according to item 1.

  (8) In the present invention, the ultrasonic vibrator is an electrostrictive vibrator having an electrostrictive element, and the driving unit applies the voltage to the electrostrictive element to The medical guide wire according to (7), which is a power supply device that vibrates ultrasonically.

  (9) In the present invention, the ultrasonic vibrator is a magnetostrictive vibrator having a magnetostrictive element, and the driving unit causes the magnetostrictive vibrator to ultrasonically vibrate by applying a magnetic field to the magnetostrictive element. The medical guide wire according to (7), wherein the medical guide wire is a drive coil.

  (10) In the present invention, the drive unit may be an ultrasonic vibration generator capable of generating ultrasonic vibration, and the ultrasonic generator resonates with the ultrasonic vibration generated from the ultrasonic vibration generator. An ultrasonic resonator that ultrasonically vibrates, and the ultrasonic vibration generated from the ultrasonic generator is configured to be transmitted to the ultrasonic resonator via the guide wire body. The medical guide wire according to any one of (1) to (6), characterized in that it is characterized.

  (11) In the present invention, the frequency of ultrasonic vibration that can be generated from the ultrasonic vibration generator is set to a frequency that is the resonance frequency of the ultrasonic resonator and not the resonance frequency of the guide wire body. The medical guide wire according to (10), characterized in that

  (12) In the present invention, any one of (1) to (11) is characterized in that a distal end portion of the guide wire body is formed of a material having flexibility and flexibility. It is the medical guide wire described in 1.

  (13) The present invention is also characterized in that the ultrasonic wave generator is disposed coaxially with the guide wire body, according to any one of (1) to (12). It is a medical guide wire.

  (14) Furthermore, the present invention is the medical guidewire according to any one of (1) to (13), which is used for crushing and melting a cerebral thrombus in a cerebral blood vessel. .

  According to the medical guide wire according to the present invention, it is not necessary to use a hollow structure catheter that is limited in size as in the case of a conventional thrombectomy catheter. The insertion is easy, and not only thrombus in blood vessels such as the heart but also thrombus in thin blood vessels such as cerebral blood vessels can be removed quickly and reliably. Further, only a weak tissue such as a thrombus can be crushed and melted by ultrasonic waves, and there is no risk of damaging the inner wall of the elastic blood vessel, so that the blood vessel can be reliably prevented from being damaged.

  In addition, the low frequency band ultrasonic waves that can be generated from the ultrasonic wave generation unit can reduce power consumption compared to the conventional case and can be a simple device, thus reducing the economic burden. Can do.

  In addition, when the output value of the drive unit is adjusted to generate an ultrasonic wave in a low frequency band, not only the thrombus attached to the blood vessel wall but also the thrombus detached from the blood vessel wall is adsorbed to the ultrasonic wave generating unit. It can be completely crushed and melted, and there is no fear that the thrombosis after crushing will flow and block the blood vessel again with peripheral blood vessels.

  Further, in the conventional thrombectomy catheter, the tip portion where the ultrasonic transducer is disposed may jump up due to vibration, and the inner wall of the blood vessel may be damaged by the catheter. It is difficult to keep the ultrasonic transducer in an appropriate position, and it is difficult to continuously apply vibration in a certain direction to the thrombus. In that respect, if the ultrasonic wave generator is disposed at a predetermined interval from the tip of the guide wire body, the tip of the ultrasonic wave generator does not jump due to vibration of the ultrasonic wave generator, and the inner wall of the blood vessel In addition, there is no risk of damaging the surrounding organs and the ultrasonic generator can be kept in an appropriate position, and the ultrasonic waves generated from the ultrasonic generator can be stably supplied to the thrombus. it can.

  Furthermore, if the ultrasonic wave generator is an ultrasonic vibration body capable of performing ultrasonic vibration by deforming itself, it is not necessary to apply ultrasonic vibration from the outside, and an apparatus for generating ultrasonic vibration is not necessary. It becomes.

  Further, the ultrasonic vibrator is an electrostrictive vibrator having an electrostrictive element, and the drive unit supplies a voltage to the electrostrictive element to vibrate the electrostrictive vibrator ultrasonically. If so, it is possible to generate ultrasonic waves by electric energy.

  Further, the ultrasonic vibrator is a magnetostrictive vibrator having a magnetostrictive element, and the drive unit is a magnetic coil as long as it is a drive coil that ultrasonically vibrates the magnetostrictive vibrator by applying a magnetic field to the magnetostrictive element. It becomes possible to generate ultrasonic waves by energy.

  Further, the drive unit is an ultrasonic vibration generator capable of generating ultrasonic vibration, and the ultrasonic generator resonates with the ultrasonic vibration generated from the ultrasonic vibration generator and performs ultrasonic vibration. If the ultrasonic vibration generated from the ultrasonic generator is configured to be transmitted to the ultrasonic resonator via the guide wire body, the drive unit is the ultrasonic generator. It is possible to arrange it at a position away from the head, increasing the degree of freedom of design, and because the ultrasonic waves generated outside are not blocked by the skull etc., Can also be used.

  Furthermore, if the frequency of ultrasonic vibration that can be generated from the ultrasonic vibration generator is set to a frequency that is the resonance frequency of the ultrasonic resonator and not the resonance frequency of the guide wire body, the ultrasonic wave Only the ultrasonic resonator can be ultrasonically vibrated by the vibration generator, and there is no possibility that the guide wire body vibrates and damages the blood vessel and surrounding organs.

  Further, if the distal end portion of the guide wire main body is formed of a material having flexibility and flexibility, the guide wire main body can be smoothly moved in a tortuous blood vessel, and the blood vessel may be damaged. There is no.

  Furthermore, if the ultrasonic wave generating portion is coaxially disposed on the guide wire main body, the radial dimension of the guide wire main body can be made compact while having the ultrasonic wave generating portion, and the cerebral blood vessel Even a blood vessel that is branched in a complicated manner, such as a thin and winding vessel, can be easily inserted. Note that “coaxial” means that the axis of the guide wire main body and the axis of the ultrasonic wave generating section are on substantially the same straight line.

  Furthermore, as described above, the medical guide wire according to the present invention is suitable for crushing and melting a cerebral thrombus in a cerebral blood vessel because it can be easily inserted into a stenotic or meandering blood vessel.

  Hereinafter, medical guidewires according to Examples 1 to 3 of the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 is a schematic external view schematically showing the appearance of a medical guide wire 10 according to a first embodiment of the present invention, and FIG. 2 is a partially enlarged view showing an enlarged main part of the medical guide wire 10. FIG.

  The medical guide wire 10 according to the first embodiment includes an ultrasonic vibrator 14 (an “ultrasonic wave generator” according to the present invention) disposed in the guide wire main body 12, and the ultrasonic vibrator 14 as an ultrasonic wave. And a power supply device 16 that vibrates (“driving unit” according to the present invention).

  As the guide wire body 12, a conventionally known guide wire generally used for guiding a medical instrument such as a catheter to a predetermined position in a body cavity such as a blood vessel can be applied. For example, stainless steel, gold, It can be formed of a metal such as platinum, aluminum, tungsten, tantalum, or an alloy thereof.

  Further, the distal end portion 12A of the guide wire main body 12 is preferably formed of a material having flexibility and flexibility so that it can be easily inserted into a tortuous blood vessel and does not damage the inner wall of the blood vessel. For example, it can be formed of a material such as a tapered stainless alloy.

  Further, the thickness of the guide wire body 12 is not limited, but is preferably 0.1 to 1 mm, particularly preferably 0.36 to 0.89 mm, and particularly about 0.36 mm when used in a cerebral blood vessel. When used in blood vessels, it is preferably about 0.89 mm.

  A conventional thrombectomy catheter (for example, the catheter described in Patent Document 1) in which an ultrasonic transducer is disposed at the distal end portion can be applied only to a thick blood vessel such as a heart blood vessel that is not so bent. However, the medical guide wire 10 according to the first embodiment employs a thin guide wire body 12 for guiding a catheter or the like to a predetermined position in a body cavity such as a blood vessel. Even a complicated and branched blood vessel that is thin and tortuous can be easily inserted, and a cerebral thrombus or the like in the cerebral blood vessel can be removed. Further, since the distal end portion of the guide wire main body 12 is formed of a material having flexibility and flexibility, the guide wire main body 12 can be smoothly moved in a tortuous blood vessel, and the blood vessel may be damaged. Nor.

  The ultrasonic vibrator 14 is coaxial with the guide wire main body 12 (with the axis of the guide wire main body 12 at a predetermined interval L (in this embodiment, L = about 3 cm) from the tip of the guide wire main body 12. The ultrasonic vibrator 14 is disposed so that the axial centers thereof are located on substantially the same straight line.

  In the conventional catheter for removing a thrombus, the tip portion where the ultrasonic transducer is disposed may be jumped by vibration, so that the inner wall of the blood vessel may be damaged by the catheter. It is difficult to keep the vibrator in an appropriate position, and it is difficult to continuously apply vibration in a certain direction to the thrombus. On the other hand, in the medical guide wire 10 according to the first embodiment, since the ultrasonic vibrator 14 is disposed at a predetermined interval L from the tip of the guide wire main body 12, the tip is caused by the vibration of the ultrasonic transducer 14. The portion does not jump off, there is no risk of damaging the inner wall of the blood vessel and the surrounding organs, and the ultrasonic transducer 14 can be kept at an appropriate position, and is generated from the ultrasonic transducer 14. Ultrasound can be stably supplied to the thrombus. Further, since the ultrasonic vibrating body 14 is coaxially disposed on the guide wire main body 12, the radial dimension of the guide wire main body 12 can be made compact while the ultrasonic vibrating body 14 is provided, and the brain Even a blood vessel that is branched in a complicated manner, such as a blood vessel, can be easily inserted.

  In the first embodiment, the ultrasonic vibrating body 14 is an electrostrictive vibrator including a substantially cylindrical electrostrictive element. Here, an “electrostrictive element (also called a piezoelectric element)” refers to an element that expands and contracts (transforms) minutely by applying a voltage, such as lead zirconate titanate, lead titanate, Representative examples include lead zirconate titanate, lead zirconate, lead lanthanum titanate, lead lanthanum zirconate titanate, lead magnesium niobium zirconate, crystal, and rubidium. Note that the electrostrictive vibrator may be configured to have an electrostrictive element at least partially. For example, the electrostrictive vibrator may be formed by combining the electrostrictive element and another element.

  Further, as shown in an enlarged view in FIG. 2, lead wires 18 extending from the power supply device 16 are connected to both ends of the ultrasonic vibrator 14 in the axial direction. The power supply device 16 is configured to be able to apply a predetermined voltage in the axial direction of the ultrasonic vibrator 14 via the lead wire 18, and by adjusting the frequency of this voltage, the ultrasonic vibrator 14. Can be ultrasonically vibrated at a desired frequency in the axial direction (in the direction of arrow A in FIG. 2), and ultrasonic waves having a desired frequency can be generated from the ultrasonic vibrator 14.

  Note that the frequency of the voltage applied by the power supply device 16 (adjustable in the frequency band of 58 kHz to 130 kHz in the present embodiment) (the frequency of the ultrasonic wave generated from the ultrasonic vibrator 14) is the blood vessel diameter or thrombus. It may be adjusted according to the amount and the like, and is not particularly limited, but preferably a low frequency band of 35 kHz to 95 kHz, particularly preferably 50 kHz to 70 kHz.

  Further, the output of the power supply device 16 is preferably 9 W to 50 W, particularly preferably 15 W to 35 W. The thrombectomy catheter disclosed in Patent Document 1 “vibrates and destroys” a thrombus using ultrasonic waves in a low frequency band of about 15 kHz to 30 kHz, but the medical guide wire 10 according to the first embodiment. For example, if the output is adjusted to 20 W so as to obtain an ultrasonic wave of 60 kHz, not only the thrombus adhering to the blood vessel wall but also the thrombus detached from the blood vessel wall can be adsorbed to the ultrasonic wave generation unit and completely It can be crushed and melted, and there is no fear that the thrombi after crushing will flow and block the blood vessel again with peripheral blood vessels. An output value of 9 W or less is not preferable because the detached thrombus is not adsorbed. On the other hand, an output value of 50 W or more is not preferable because there is a risk of damaging the blood vessel.

  FIG. 3 is a diagram schematically illustrating a state in which the medical guide wire 10 according to the first embodiment is inserted into a blood vessel, and FIG. 4 is a diagram schematically illustrating a state in which a thrombus is crushed and melted by the medical guide wire 10. FIG.

  First, blood vessels 20 such as the heart and brain are examined by X-ray examination, ultrasonic diagnosis, etc., and a thrombus 22 formed in the blood vessel 20 is specified. At this time, the frequency of the voltage applied by the power supply device 16 is determined according to the blood vessel diameter of the blood vessel 20 and the amount of the thrombus 22.

  Next, for example, under X-ray fluoroscopy, as shown in FIG. 3, the guide wire main body 12 is inserted into the blood vessel 20 and set so that the ultrasonic vibrator 14 is positioned in the vicinity of the thrombus 22. Then, a voltage having a desired frequency is applied to the ultrasonic vibrator 14 using the power supply device 16. As a result, the ultrasonic vibrating body 14 vibrates ultrasonically according to the frequency of the voltage (repeatedly expanding and contracting at high speed), and the ultrasonic wave W is directly applied to the thrombus 22 or indirectly via blood. give. As a result, as shown in FIG. 4, the thrombus 22 is emulsified and melted by the ultrasonic wave W.

  As described above, according to the medical guidewire 10 according to the first embodiment, the ultrasonic wave generator (which is disposed in the guidewire main body 12 and can generate ultrasonic waves to the outside) And a drive unit (power supply device 16 in the first embodiment) that vibrates this ultrasonic wave generator ultrasonically, and crushes and melts the thrombus in the blood vessel using ultrasonic waves. Therefore, it is not necessary to use a hollow structure catheter that is limited in size as in the case of a conventional thrombectomy catheter, so it can be easily inserted into a blocked blood vessel or a blood vessel with strong stenosis or meandering. It is possible to quickly and reliably remove a thrombus in a thin blood vessel such as a cerebral blood vessel. Further, only a weak tissue such as a thrombus can be crushed and melted by ultrasonic waves, and there is no risk of damaging the inner wall of the elastic blood vessel, so that the blood vessel can be reliably prevented from being damaged.

  In addition, since the ultrasonic generator is an ultrasonic vibrating body capable of ultrasonic vibration by being deformed, it is not necessary to apply ultrasonic vibration from the outside, and an apparatus for generating ultrasonic vibration is not necessary. .

  Furthermore, the ultrasonic vibrator 14 is an electrostrictive vibrator having an electrostrictive element, and the drive unit is a power supply device 16 that ultrasonically vibrates the electrostrictive vibrator by applying a voltage to the electrostrictive element. Therefore, ultrasonic waves can be generated by electric energy.

  FIG. 5 is a schematic external view schematically showing the appearance of the medical guide wire 30 according to the second embodiment of the present invention, and FIG. 6 is a partially enlarged view showing the main part of the medical guide wire 30 in an enlarged manner. FIG.

  The medical guide wire 30 according to the second embodiment includes an ultrasonic vibrator 34 (an “ultrasonic wave generator” according to the present invention) disposed in the guide wire main body 32, and the ultrasonic vibrator 34. A drive coil 36 to be oscillated (a “drive unit” according to the present invention) and a power supply device 38 that supplies a drive current to the drive coil 36 are configured. Since the guide wire body 32 has the same structure as the guide wire body 12 according to the first embodiment, the description thereof is omitted.

  In the second embodiment, the ultrasonic vibrator 34 is configured by a magnetostrictive vibrator including a substantially disk-shaped magnetostrictive element instead of the electrostrictive vibrator according to the first embodiment. Here, the “magnetostrictive element” refers to an element that slightly expands and contracts (deforms) by a so-called magnetostrictive effect when a magnetic field is applied. For example, nickel, ferrite, and the like are typical examples. The magnetostrictive vibrator may be configured to have at least a part of the magnetostrictive element. For example, the magnetostrictive vibrator may be formed by combining the magnetostrictive element and another element. Furthermore, instead of the magnetostrictive element, a super magnetostrictive element can also be applied. In this case, the amplitude of the ultrasonic vibrator 34 can be further increased.

  Further, the ultrasonic vibrator 34 is spaced from the tip of the guide wire main body 32 by a predetermined distance (similar to the first embodiment, about 3 cm from the tip), and its axis is relative to the axis of the guide wire main body 32. Are arranged so as to be substantially orthogonal.

  Further, as shown in an enlarged view in FIG. 6, a drive coil 36 is wound around the radially outer peripheral surface of the ultrasonic vibrator 34, and the drive coil 36 extends from a power supply device 38. A lead wire 40 is connected. The drive coil 36 is configured to be able to apply a magnetic field in the axial direction of the ultrasonic vibrator 34 based on the drive current supplied from the power supply device 38 via the lead wire 40, and adjusts this magnetic field. Thus, the ultrasonic vibrator 34 can be ultrasonically vibrated at a desired frequency in the axial direction (the direction of arrow B in FIG. 6), and the ultrasonic vibrator 34 can generate an ultrasonic wave having a desired frequency. is there.

  In the medical guide wire 30 according to the second embodiment, as in the medical guide wire 10 according to the first embodiment, for example, under X-ray fluoroscopy, the guide wire main body 32 is inserted into the blood vessel, and the ultrasonic vibrator Set so that 34 is located in the vicinity of the thrombus. Then, a magnetic field having a desired frequency is applied to the ultrasonic vibrator 34 using the drive coil 36. Thereby, the ultrasonic vibrating body 34 ultrasonically vibrates in accordance with the frequency of the magnetic field (repeats high-speed minute expansion and contraction), and applies ultrasonic waves directly to the thrombus or indirectly through blood. . As a result, the thrombus is emulsified and melted by ultrasonic waves.

  As described above, according to the medical guide wire 30 according to the second embodiment, the ultrasonic vibrator 34 is a magnetostrictive vibrator having a magnetostrictive element, and the drive unit applies a magnetic field to the magnetostrictive element to thereby generate the magnetostrictive vibrator. Therefore, it is possible to generate ultrasonic waves by magnetic energy.

  In Examples 1 and 2 described above, an electrostrictive vibrator or a magnetostrictive vibrator is applied as the “ultrasonic vibrator” according to the present invention. However, the present invention is not limited to this and is deformed by itself. Any ultrasonic vibration body capable of ultrasonic vibration can be used.

  FIG. 7 is a schematic external view schematically showing the external appearance of the medical guide wire 50 according to the third embodiment of the present invention.

  The medical guide wire 50 according to the third embodiment includes an ultrasonic resonator 54 (an “ultrasonic wave generator” according to the present invention) disposed in the guide wire body 52 and an ultrasonic wave that can generate ultrasonic vibration. And a vibration generator 56 ("driving unit" according to the present invention). Since the guide wire body 52 has the same structure as the guide wire body 12 according to the first embodiment, the description thereof is omitted.

  The ultrasonic resonator 54 is not particularly limited as long as it can resonate with ultrasonic vibration generated from the ultrasonic vibration generator 56 and can be ultrasonically vibrated. For example, platinum (sound velocity V = 3260 m) is used. / S), iron (sound speed V = 5950 m / s), stainless steel (sound speed V = 5790 m / s), titanium (sound speed V = 5990 m / s), and the like. When the ultrasonic frequency f is set to 1 MHz, the length dimension a in the axial direction of the ultrasonic resonator 54 can be calculated by “a = V / 2f”, 1.63 mm for platinum, It is 2.98 mm for iron, 2.90 mm for stainless steel, and 3.00 mm for titanium. When the ultrasonic frequency f is set to 30 MHz, the length a of the ultrasonic resonator 54 is 0.54 mm for platinum, 0.99 mm for iron, 0.97 mm for stainless steel, and 1.00 mm for titanium. Become.

  The ultrasonic vibration generator 56 is configured to be able to generate ultrasonic vibration, and this ultrasonic vibration is transmitted to the ultrasonic resonator 54 via the guide wire body 52. The frequency of ultrasonic vibration that can be generated from the ultrasonic vibration generator 56 is set to a frequency that is the resonance frequency of the ultrasonic resonator 54 and not the resonance frequency of the guide wire body 52. Therefore, only the ultrasonic resonator 54 can be ultrasonically vibrated by the ultrasonic vibration generator 56, and there is no possibility that the guide wire body 52 vibrates and damages the blood vessel and surrounding organs.

  Moreover, in the catheter of patent document 2, since the ultrasonic wave from an external ultrasonic generator is interrupted | blocked with a skull, it cannot utilize for the thrombus in a cerebral blood vessel, On the other hand, it is medical use which concerns on this Example 3. The guide wire 50 can be used without any problem for a thrombus in a cerebral blood vessel covered with a skull.

  Similar to the medical guide wire 10 according to the first embodiment, the medical guide wire 50 according to the third embodiment inserts the guide wire main body 52 into the blood vessel under, for example, fluoroscopy, and an ultrasonic resonator. Set so that 54 is located near the thrombus. Then, by ultrasonically vibrating the ultrasonic resonator 54 at a desired frequency using the ultrasonic vibration device 56, ultrasonic waves are directly applied to the thrombus or indirectly via blood. As a result, the thrombus is emulsified and melted by ultrasonic waves.

  Thus, according to the medical guide wire 50 according to the third embodiment, the driving unit is the ultrasonic vibration generating device 56 capable of generating ultrasonic vibration, and the ultrasonic generating unit is the ultrasonic vibration generating device. An ultrasonic resonator 54 that resonates with the ultrasonic vibration generated from 56 and vibrates ultrasonically, and the ultrasonic vibration generated from the ultrasonic generator 56 is transmitted to the ultrasonic resonator 54 via the guide wire body 52. Therefore, the drive unit (in this example, the ultrasonic generator 56) can be disposed at a position away from the ultrasonic generator (in this example, the ultrasonic resonator 54). The degree of design freedom can be increased.

  The medical guide wire according to the present invention can be applied to the removal of a thrombus in a blood vessel, and is particularly suitable for the removal of a brain thrombus in a cerebral blood vessel.

BRIEF DESCRIPTION OF THE DRAWINGS It is the outline external view which showed typically the external appearance of the medical guide wire which concerns on Example 1 of this invention. It is the elements on larger scale which expanded and showed the principal part of the medical guide wire. It is the figure which showed typically a mode that the medical guide wire was inserted in the blood vessel. It is the figure which showed typically a mode that the thrombus was crushed and melt | dissolved by the medical guide wire. It is the outline external view which showed typically the external appearance of the medical guide wire which concerns on Example 2 of this invention. It is the elements on larger scale which expanded and showed the principal part of the medical guide wire. It is the outline external view which showed typically the external appearance of the medical guide wire which concerns on Example 3 of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10, 30, 50 ... Medical guide wire 12, 32, 52 ... Guide wire main body 14, 34 ... Ultrasonic vibrator 16, 38 ... Power supply device 18, 40 ... Lead wire 20 ... Blood vessel 22 ... Thrombus 36 ... Drive coil 54 ... Ultrasonic resonator 56 ... Ultrasonic vibration generator

Claims (14)

An ultrasonic generator disposed in the guide wire body and capable of generating ultrasonic waves outside;
A drive unit for ultrasonically vibrating the ultrasonic wave generation unit,
The thrombus in the blood vessel is crushed and melted by the ultrasonic wave,
Medical guide wire. The ultrasonic frequency band that can be generated from the ultrasonic wave generator is 35 kHz to 95 kHz,
The medical guide wire according to claim 1. The frequency band of ultrasonic waves that can be generated from the ultrasonic wave generation unit is 50 kHz to 70 kHz,
The medical guide wire according to claim 1. The output of the drive unit is 9W-50W,
The medical guide wire according to any one of claims 1 to 3. The output of the drive unit is 15W to 35W,
The medical guide wire according to any one of claims 1 to 3. The ultrasonic wave generator is disposed at a predetermined interval from the tip of the guide wire body,
The medical guide wire according to any one of claims 1 to 5. The ultrasonic generator is an ultrasonic vibrator capable of ultrasonic vibration when deformed by itself.
The medical guide wire according to any one of claims 1 to 6. The ultrasonic vibrator is an electrostrictive vibrator having an electrostrictive element,
The drive unit is a power supply device that ultrasonically vibrates the electrostrictive vibrator by applying a voltage to the electrostrictive element.
The medical guide wire according to claim 7. The ultrasonic vibrator is a magnetostrictive vibrator having a magnetostrictive element,
The drive unit is a drive coil that ultrasonically vibrates the magnetostrictive vibrator by applying a magnetic field to the magnetostrictive element.
The medical guide wire according to claim 7. The drive unit is an ultrasonic vibration generator capable of generating ultrasonic vibrations,
The ultrasonic generator is an ultrasonic resonator that resonates with ultrasonic vibration generated from the ultrasonic vibration generator and vibrates ultrasonically,
The ultrasonic vibration generated from the ultrasonic generator is configured to be transmitted to the ultrasonic resonator via the guide wire body.
The medical guide wire according to any one of claims 1 to 6. The frequency of ultrasonic vibration that can be generated from the ultrasonic vibration generator is set to a frequency that is the resonance frequency of the ultrasonic resonator and not the resonance frequency of the guide wire body,
The medical guide wire according to claim 10. The distal end portion of the guide wire body is formed of a material having flexibility and flexibility,
The medical guide wire according to any one of claims 1 to 11. The ultrasonic generator is coaxially disposed on the guide wire body,
The medical guide wire according to any one of claims 1 to 12. It is used to crush and melt cerebral thrombi in cerebrovascular,
The medical guide wire according to any one of claims 1 to 13.

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