JPH0613687Y2 - Tip cover for ultrasonic surgical equipment - Google Patents

Description

[Detailed description of the device]

[0001]

[Industrial applications]

The present invention relates to a plastic protective cover provided outside a tip of a handpiece tip of a surgical operating apparatus having a function of crushing cells by ultrasonic vibration.

[0002]

[Prior art]

In a surgical device having a function of disrupting cells by ultrasonic vibration, conventionally, mechanical high-speed vibration under ultrasonic frequency is performed outside the tip connected to the horn at the tip of the handpiece. For the purpose of preventing the side surface of the chip from coming into contact with normal living tissue and ensuring an irrigation liquid passage, a protective cover is provided to cover the vicinity of the tip of the chip.

In the case where the protective cover is long, that is, in the case where the tip has a node having an axial vibration amplitude on the tip, the length of the protective cover is inevitably long, and as a result, the protective cover is provided. It becomes difficult to hold the cover and the chip concentrically, and the inner surface of the protective cover comes into contact with the outer surface of the chip that is vibrating mechanically at high speed with ultrasonic waves.
In this case, ultrasonic vibration is propagated to the protective cover, and further, ultrasonic vibration is propagated to normal tissue in contact with the outer surface of the protective cover, which may cause damage.
Further, when the protective cover is made of plastics, the protective cover in the portion in contact with the chip may be melted by frictional heat.

A conventional method will be described below with reference to the drawings. FIG. 3 shows a conventional handpiece tip having no knot in the tip portion, and FIG. 4 shows a conventional handpiece tip having a knot in the tip portion. It is sectional drawing which shows the mounting state of a horn, a chip | tip part, and a protective cover, (b) is a figure which shows the pattern of the vibration amplitude of the horn and a chip | tip part of an axial direction.

The length of the horn (1) and the chip (2) of FIG. 3 is a length corresponding to 1/2 of the wavelength λ of the ultrasonic wave, as shown in FIG. Alternatively, although the magnetostrictive vibrator is not shown, it is connected to the left side of the drawing by the screw part (3) of the horn (1), and the length of these ultrasonic vibrators is normally 1 / 2λ. Therefore, the total length of the handpiece is
Takes 1λ resonance. The horn (1) and the chip (2) are connected by a screw part (4). The vibration amplitude in the axial direction of the horn (1) and the tip (2) has an antinode of vibration on the left end face of the horn (1), that is, the portion connected to the ultrasonic transducer, as shown in FIG. This vibration amplitude is the horn (1)
Node (7) that becomes smaller toward the tip (2) side of the horn (1) and the vibration amplitude becomes zero at the position of the horn shoulder (6) corresponding to the length equivalent to 1/4 from the left end surface of the horn (1). ) Is formed. Horn shoulder (6) to tip (2)
The part that shifts to the side has a conical shape, and the vibration amplitude increases in inverse proportion to the cross-sectional area, and is approximately 1 / 4λ from the node (7).
An antinode (8) having a vibration amplitude is formed at the portion that has shifted to the right.
The ultrasonic resonance state can be obtained by determining the length of the tip (2) so that the position of the antinode (8) is exactly the tip of the tip (2).

The tip (2) vibrates at a high speed under ultrasonic frequency and has a high vibration amplitude as shown in FIG. (B). Therefore, when the outer surface of the tip (2) contacts normal tissue, Therefore, the chip cover (9) is provided concentrically without contacting the chip (2). The tip cover (9) is connected to the horn cover (10) which is not in contact with the outer periphery of the horn (1) by a screw (11) or the like.

An irrigation liquid inlet (12) is provided near the conical portion of the horn cover (10), and a nipple or the like (not shown) is used for the irrigation liquid inlet (1).
Installed in 2), connect the saline bottle to this nipple by tube piping. Irrigation liquid inlet (1
An O-ring is inserted on the left side of 2), that is, on the oscillator side to prevent the irrigation liquid from flowing into the oscillator side. The irrigation liquid passes through an annular passage formed by the inner surface of the tip cover (9) and the outer surface of the tip (2), and the mechanical vibration action of ultrasonic waves of the tip (2) from the tip of the tip cover (9). By this, it is sprayed in a mist form on the surgical target site. The tissue crushed by the mechanical vibration of the tip (2) and emulsified by the irrigation liquid passes through the tip (2) and the suction hole (14) in the horn (1) and passes through the ultrasonic transducer (not shown). It is sucked out of the body through the through hole.

The material of the chip (2) and the horn (1) is
Titanium alloys, high-strength aluminum alloys, and stainless steels are desirable as those that can withstand mechanical vibrations under high frequencies of ultrasonic waves, and titanium alloys are particularly desirable because they have high toughness. The material of the chip cover (9) is preferably made of synthetic resin capable of absorbing the vibration of the chip (2) when it comes into contact with the chip (2).

The handpiece shown in FIG. 4 is obtained by lengthening the tip (15) by 1 / 2λ so as to be useful for crushing and removing a deep tumor such as in neurosurgery.
The tip cover (16) also becomes longer accordingly. When the tip (2) shown in FIG. 3 (a) has a length of about 1 / 4λ, the tip cover (9) is normally attached to the tip (2).
The tip (15) and the tip cover (16) are held concentrically when the tip (15) and the tip cover (16) are long as shown in FIG. If the operator holds the outer surface of the tip cover (16) for an operation or if normal tissue hits this portion, the tip cover (16) is a machine under ultrasonic frequency. When the tip (15) vibrating at a high speed is contacted, frictional heat is generated in that portion, and the tip cover (16) made of synthetic resin is damaged by melting or the like, and the tip (15) vibrates. There is a risk that it may be propagated via 16) to normal tissue in contact with the outer surface of the tip cover (16) and cause tissue damage. In the example of FIG. 4, the chip (15) is lengthened by ½λ as compared with FIG. 3, but when the length is further increased by ½λ unit, the above phenomenon is magnified.

[0010]

[Problems to be solved by the device]

The present invention relates to the above-described conventional handpiece for an ultrasonic surgical apparatus, in which the tip cover (16) has a tip (1
The present invention intends to provide a novel handpiece for an ultrasonic surgical apparatus which has a drawback that normal tissue is damaged by contact with (5) and which does not cause such a defect.

[0011]

[Means for Solving the Problems]

That is, the present invention is a tip cover to be attached to the outer surface of the tip, which is a length having a node having a vibration amplitude, which is attached to the tip of a handpiece of an ultrasonic surgical device having a function of crushing biological tissue by ultrasonic vibration. In the above, there is provided a tip cover for an ultrasonic surgical device, characterized in that a holding ring portion having a diameter equal to or larger than an outer diameter of the tip and a dimension larger than an inner diameter of the tip cover is provided at a position corresponding to the node portion. .

An embodiment of the present invention will be described in detail below with reference to FIGS. 1 and 2. FIG. 1A is a chip (15) obtained by extending the chip (2) shown in FIG. 3 by 1 / 2λ as in FIG.
And a chip cover (17) according to the present invention, which is shown in FIG.
(B) shows the pattern of the vibration amplitude in the axial direction.

As is clear from the vibration amplitude pattern of FIG. 1 (b), there is a first node (18) near the horn shoulder (6), and from the position of this first node (18). Roughly 1/2
λ, has a second node (19) on the tip end side. First
The first abdomen (20) and the second node (19) are located approximately in the middle of the node (18) and the second node (19) of the second node (19). The resonance state can be obtained by determining the length of the tip (15) so that the size becomes the abdomen (21) of the.

As the material of the tip (15), titanium alloy, stainless steel, duralumin, etc. are suitable as in the prior art, and titanium alloy is more preferable as the tip material for ultrasonic surgery.

The chip cover (17) according to the present invention is made of synthetic resin, and any of thermoplastic resin such as polyethylene resin and polysulfone resin and thermosetting resin such as epoxy resin and phenol resin can be used. From the viewpoint of mechanical strength, chemical resistance, and workability, polysulfone resin is most desirable.

The chip cover (17) made of these synthetic resins has a pipe shape provided outside the pipe-shaped chip (15), and the outer surface of the chip (15) and the chip cover (17). The physiological saline introduced from the irrigation liquid inlet (12) flows through the annular passage (22) formed by the inner surface of the tip of the tip cover (17) and is ejected in a mist state.

A retaining ring portion (23) is provided inside the tip cover (17) at a position corresponding to the second node portion (19) of the tip (15). This retaining ring (23)
Is integrated with the chip cover (17), and its shape will be described in detail with reference to FIG.

FIG. 2 is a sectional view taken along the line AA 'of FIG. FIG. 2A shows an embodiment in which the retaining ring portion (23) has an annular shape, and the retaining ring has an inner diameter larger than the outer diameter of the tip to form the slit portion (24). When the outer diameter of the chip is 3 mm and the inner diameter of the chip cover is 5 mm, the gap between the slits is 0.2 to 0.5 mm.
Is desirable. The physiological saline that has flowed in from the irrigation liquid inlet (12) flows through the annular passage (22), passes through the slit portion (24) of the retaining ring portion (23), and flows out from the tip end portion of the tip cover (17). .

With this configuration, when force is applied from the outer side surface of the tip cover (17) during surgery, only the retaining ring portion (23) comes into contact with the tip (15). Since this contact portion is provided at the position of the second node portion (19) of the vibration amplitude of the tip (15), the retaining ring portion (23) generates frictional heat due to contact with the tip (15). Moreover, the vibration of the entire chip (15) is not adversely affected. Moreover, the irrigation liquid passes through the slit portion other than the contact portion between the retaining ring portion (23) and the tip (15), and is sent to the tip end portion of the tip cover (17) without obstructing the flow.

FIG. 2B shows an embodiment in which the retaining ring portion (23) is provided with four semicircular fluid passages (25).
The holding ring portion (26) is provided with four contact portions (27) that come into contact with the tip (15) or have a gap of about 0.05 to 0.1 mm. In addition, FIG.
The retaining ring portion (30) is provided with eight triangular fluid passages (28), and the retaining ring portion (30) is provided.
Contact the tip (16) at eight locations, or 0.
This is an example having a gap of about 05 to 0.1 mm.

As described above with reference to FIG. 2A, FIG.
In both (c), since the retaining ring portions (26) and (30) are located at the second node portion (19) of the vibration amplitude, the contact portion (2
7) and (29) are not affected by frictional heat or the like even when they contact the tip (15), and the fluid passages (25) and (28)
There is also an effect that can take a large. 2 (b),
In the example of (c), four arc-shaped fluid passages,
Although the description has been made using eight triangular fluid passages, two or more of these fluid passages are effective.

The embodiment described with reference to FIGS. 1 and 2 is an example in which the retaining ring portion is provided at the second node portion.
It is within the scope of the present invention to provide one or a plurality of retaining ring portions at arbitrary nodes even if the chip has a length that is an integral multiple of 1 / 2λ.

[0023]

[Effect of device]

The protective cover for the ultrasonic surgical device of the present invention does not generate frictional heat even when it comes into contact with the tip of the handpiece portion that is vibrating ultrasonically, and does not become a load of ultrasonic vibration. Also, it has the effect of facilitating the circulation of the irrigation liquid, has the function of performing safe surgery without obstructing the field of view even for surgery performed in a narrow field of view, and has a medical advantage. It is also extremely superior industrially.

[Brief description of drawings]

FIG. 1A is a sectional view showing a state in which a tip cover according to the present invention is mounted, and FIG. 1B is a view showing a vibration amplitude pattern in an axial direction thereof.

FIG. 2 is a cross-sectional view taken along the line AA ′ of FIG. 1, showing the shape of a retaining ring portion.

FIG. 3A is a cross-sectional view showing a state where a conventional tip cover is attached to a handpiece having no vibration amplitude node in the tip portion, and FIG. 3B shows a vibration amplitude pattern in the axial direction. FIG.

FIG. 4A is a sectional view showing a state where a conventional tip cover is attached to a handpiece having a vibration amplitude node in a tip portion, and FIG. 4B shows a vibration amplitude pattern in the axial direction. It is a figure.

[Explanation of reference numerals] 1 horn 2,15 tip 5,8,20,21 abdomen 7,18,19 nodal portion 9,16,17 tip cover 22 annular passage 23,26,30 retaining ring portion 24 slit portion 25,28 Fluid passage

Claims (1)

[Scope of utility model registration request] 1. A tip cover to be attached to an outer surface of a tip having a length having a vibration amplitude node, which is attached to the tip of a handpiece of an ultrasonic surgical apparatus having a function of crushing biological tissue by ultrasonic vibration. 2. A tip cover for an ultrasonic surgical apparatus, characterized in that a holding ring portion having a diameter equal to or larger than the outer diameter of the tip and larger than the inner diameter of the tip cover is provided at a position corresponding to the node portion.