JPH0529697Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a surgical tool for cutting biological tissue using ultrasonic vibrations.

[Conventional technology]

Traditionally, wire saws, electric or pneumatic saws (bonesaws), surgical burrs, etc. have been used to cut biological tissues, especially hard tissues, in fields such as neurosurgery, orthopedics, plastic surgery, and oral surgery.
Wire saws require preparatory work such as drilling holes before starting cutting, which has the disadvantage of being inefficient and requiring long hours of work. In addition, bone saws, whose blades move in a straight line, can injure the dura mater, blood vessels, nerve tissue, etc. in the hard tissue by simply touching them, placing a great burden on the surgeon while working. , currently required hard tissue with fine details, especially 5 to 30 mm on one side.
The disadvantage is that it is difficult to open a window of about 100 degrees and then cover it with a cut piece after the procedure, and the frictional heat generated between the cut tooth and the biological tissue can deactivate the cut part and surrounding tissue. It was hot. Next, in the case of surgical burs, cutting is performed by rotating the drill, which has the disadvantage of generating chatter vibrations and pulling force in the rotational direction at the operator's hand. It has the disadvantage that it can cause damage to blood vessels or nerves by simply touching them, and the frictional heat generated between the drill and the biological tissue causes the cut part and surrounding tissue to lose their activity.

Surgical tools that use ultrasound have also been developed, which use the ultrasonic vibrations of an ultrasonic vibration transmission device connected to an ultrasonic vibration source to crush hard biological tissues that come in contact with them and remove them by suction. It was developed as a surgical tool (for example, Japanese Patent Publication No. 47-39197) and for cutting and separating hard and soft biological tissues.
A surgical tool having a working part made of a metal plate with cutting teeth (for example, Japanese Patent Publication No. 51-46990) is known. However, a vibrating body with a plane working part perpendicular to the vibration direction crushes and emulsifies the surface layer of hard biological tissue by ultrasonic vibration.
For surgical instruments that perform suction removal, it is difficult to deeply insert the working part into biological tissue to cut and separate the tissue because the contact resistance on the side of the working part increases, and furthermore, it is difficult to cut hard biological tissue. was inappropriate. In addition, surgical instruments that cut and separate biological tissue using ultrasonic vibrating cutting teeth have devised the shape of the working part to improve cutting efficiency, but the minimum Even if the amplitude of the working part is about 50 μm, frictional heat is generated between the working part and the biological tissue being cut, and even if the working part is made of titanium alloy, which has excellent heat conductivity, the surface temperature of several hundred degrees The disadvantage is that the tissue being cut becomes carbonized at the cut surface when the temperature is reached. Furthermore, the working part of the blade, which has a thin wall thickness of about 0.5 to 1 mm, deteriorates due to frictional heat and may break.Also, because the working part is thin, it may embed itself in the tissue, increasing contact resistance and causing the blade to break. The drawback was that pressure was applied to the shaped part, causing the ultrasonic vibration to stop.

[The problem that the idea attempts to solve]

In order to solve these problems with conventional surgical instruments, the present invention uses ultrasonic vibration to improve cutting efficiency and operational performance, and the frictional heat generated during cutting reduces biological tissue that comes into contact with the working part. In addition to preventing damage, it also prevents the mechanical strength of the working part from decreasing due to heat generated during continuous operation, reduces contact resistance to the operating part during cutting, and reduces ultrasonic vibration caused by penetration into biological tissues. It is an object of the present invention to provide a surgical instrument for cutting biological tissue that can prevent arrest.

[Means to solve the problem]

That is, the present invention is a surgical tool for cutting and separating biological tissues using ultrasonic vibrations, in which an ultrasonic vibration transmitter that is connected to an ultrasonic vibration source and generates mechanical vibrations at an ultrasonic frequency is used to cut and separate biological tissues. The working part has a contacting working part and a passage for guiding irrigation liquid to the surgical site, the working part has a spatula-shaped blade part at the tip of the beveled surface, and the blade part has one or more grooves. The surgical tool is characterized in that it has a window with a recess or a slit extending to the tip of the blade, and one side of the passage opens at the center of the beveled surface of the working part.

The invention will be described in detail below with reference to the drawings.

FIG. 1 is a diagram showing the configuration of an apparatus using a surgical tool according to an embodiment of the present invention. An electrical signal at an ultrasonic frequency is sent from the ultrasonic starting circuit 1 to an ultrasonic vibration source 7 through cables 2 and 3, and the ultrasonic vibration source 7 generates mechanical vibration at an ultrasonic frequency. As the ultrasonic vibration source 7, either a magnetostrictive type or an electrostrictive type can be used.
The vibration is then further expanded at the joint 10 of the ultrasonic vibration transmitter 8 and transmitted to the working part 9.
The working part 9 is in direct contact with biological tissue and cuts the biological tissue by mechanical vibrations at ultrasonic frequencies.

When the working part 9 is mechanically vibrating at an ultrasonic frequency, the irrigation liquid is sent from the irrigation liquid injection pump device 4 to the ultrasonic vibration transmitting device 8 through the tube 5 and the pipe 6. The type of irrigation liquid is not particularly limited, but it is preferable to use one that has little effect on biological tissue, such as physiological saline. The irrigation liquid that has passed through the pipe 6 enters through the opening 23 as shown in FIG.
It is ejected from the ejection port 12 which is open at the center of the slanted surface of the.

Further, the diameter of the irrigation liquid passage 11 and the diameter of the jet nozzle 12 are not particularly limited, but it is preferable that the diameter of the jet nozzle 12 is smaller than the diameter of the irrigation liquid passage 11 because of excellent squirting effect of the irrigation liquid. The irrigation liquid cools the working part 9 and the surrounding biological tissues, and can prevent the temperature of the working part 9 from rising due to frictional heat caused by cutting by mechanical vibrations at ultrasonic frequencies. Moreover, the generation of heat in the ultrasonic vibration transmitting tool 8 during continuous use can be suppressed by passing the irrigation liquid through the passage 11, and deterioration of the mechanical strength of the ultrasonic vibration transmitting tool 8 can be prevented. Note that the material of the ultrasonic vibration transmitter 8 is not particularly limited;
Titanium alloys with high tensile strength and fatigue strength are preferred.

3 to 5 show specific embodiments of the working part 9, and FIG. 3 shows a plurality of slits 17 provided in the spatula-shaped blade part 16 at the tip of the working part 9. A window 13 is provided and the blade portion 16 is divided into a plurality of branch blades. As a result, when the blade part 16 penetrates deeply into biological tissue during cutting, the window 1
As a result of the volume reduction in part 3, the contact resistance decreases,
It is possible to prevent a decrease in cutting speed. Furthermore, frictional heat is reduced, and the irrigation liquid transmitted through the window 13 and ejected from the spout 12 is supplied to the cut portion and cooled. FIGS. 4 and 5 show groove 1, respectively.
4. Since the recess 15 is provided, the contact resistance is reduced as in the embodiment shown in FIG. 3, thereby preventing a decrease in cutting speed and reducing frictional heat. The widths of the window 13 and the groove 14 are not particularly limited, but are preferably about 0.2 to 1.5 mm, and the edges are preferably rounded. Furthermore, the depths of the grooves 14 and the depressions 15 are not particularly limited, but are preferably 0.05 to 0.5 mm.

Furthermore, the direction in which the blade portion 16 enters the biological tissue may be at an angle with the direction of mechanical vibration of the ultrasonic frequency, and is not particularly limited. Figure 6a
1 is an embodiment in which the blade section 16 divided into branch blades by a slit 17 at the tip of the working section 9 is curved in the circumferential direction of the working section, and b is an embodiment in which it is curved in the axial direction of the working section 9. Due to this shape, the vibration of the blade portion 16 generates a compound vibration due to a combination of vibration in the axial direction and vibration in the curved direction, thereby improving cutting efficiency. The bending angle in the axial direction is not particularly limited, but it is preferably 5° to 30°, and the bending directions are preferably opposite to each other. Furthermore, twisting may be applied parallel to the axial direction.

Further, as a specific example of a shape suitable for cutting a narrow part or a curved part depending on the surgical technique, the ultrasonic vibration transmitting tool 8 may be bent before the joint part 10 and/or before the working part 9. A seventh ultrasonic vibration transmitter is used, and the axis of the working part 9 is at an angle with respect to the mechanical vibration direction of the ultrasonic vibration source.
As shown in the figure. The angle is preferably 0 to 90 degrees, preferably 0 to 60 degrees. Further, as shown in FIG. 8, the ultrasonic vibration transmitter 8 in which the working part 9 is joined by screws 18 and 19 is preferable because it allows the working part 9 to be replaced according to the intended use. Further, the material of the working part 9 is preferably titanium alloy, ceramics, particularly zirconia, silicon nitride, and composite materials.

Next, an embodiment using the surgical tool of the present invention will be described with reference to FIG. a is biological tissue 20
b shows a state in which the cutting edge of the working part 9 has penetrated into the surface, and b shows a state in which the cutting part 16 of the working part 9 has cut deeply into the surface. At this time, window 1
3, the contact area between the blade part 16 and the cut surface of the biological tissue 20 is reduced, and the irrigation liquid flows through the window 13, thereby damaging the working part 9 and the biological tissue 20. Cooling.

[Effect of idea]

According to the present invention, biological tissue, especially hard tissue, can be cut more quickly than with conventional surgical wire saws. The working part and biological tissue can be effectively cooled, preventing deterioration of the mechanical strength of the working part due to frictional heat, and preventing the active biological tissue on the surface to be cut from being destroyed and maintaining its activity. It is suitable as a surgical tool for cutting biological tissue. In particular, there is a window in the blade part of the working part.
By providing grooves, depressions, etc., it is possible to minimize the contact resistance between the working part and the biological tissue, improve cutting efficiency, and reduce the generation of frictional heat. Furthermore, the surgical tool of this invention, which has a cooling effect due to the injection of irrigation liquid, does not cause shaft vibrations that are applied to the operator's hands during cutting, and allows for precise work, compared to conventional surgical culverts that have a rotating drill structure. . In addition, compared to conventional surgical tools for cutting that utilize ultrasonic vibration, cooling with irrigation fluid can maintain the activity of biological tissue around the cut site, improving the recovery status of the cut site after surgery. However, it is suitable as a surgical tool.

Furthermore, in the case of surgical culvers and bone saws, just touching blood vessels and nerve tissue in hard tissue causes damage, but in the case of the surgical tool of this invention,
Ultrasonic vibrations as small as 200 μm have the advantage of causing almost no damage to elastic soft tissues such as blood vessels and nerves when they come into contact with them.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the configuration of an apparatus using a surgical tool according to the present invention. FIG. 2 is a diagram showing an embodiment of the present invention, in which a is a schematic diagram showing the structure of an ultrasonic vibration transmitting tool, and b is a schematic diagram showing a working part.
Figures 3 to 5 are diagrams showing the shape of the working part as a specific example, where a is a top view and b is a top view.
FIG. Fig. 6 is a diagram showing the shape of the working part of another embodiment, Fig. 7 is an ultrasonic vibration transmitter bent before the joint, Fig. 7b is an example of the ultrasonic vibration transmitter bent before the working part, FIG. 8 is a diagram showing a detachable working part. Moreover, FIG. 9 is a diagram showing an example of use of the surgical tool according to the present invention.

Claims (1)

[Claims for Utility Model Registration] (1) A surgical tool for cutting and separating biological tissue using ultrasonic vibrations, which is connected to an ultrasonic vibration source and transmits ultrasonic vibrations that generates mechanical vibrations at ultrasonic frequencies. a working part where the tool comes into contact with biological tissue;
and a passage for guiding irrigation fluid to the surgical site, the working part having a spatula-shaped blade at the tip of the beveled surface, and the blade having one or more grooves, depressions, or blades. 1. A surgical tool, characterized in that the window has a slit extending to the tip of the working part, and one side of the passage opens at the center of the beveled surface of the working part. (2) In the surgical tool according to claim (1), in which the working part has a window in the blade part, the blade part divided into a plurality of branch blades by the slit also extends in the circumferential direction of the working part. A surgical instrument characterized by being uniquely curved in the axial direction. (3) The ultrasonic vibration transmitter is bent in front of the joint and/or in front of the working part, and the axis of the working part is at an angle with respect to the mechanical vibration direction of the ultrasonic vibration source. The surgical tool according to claim (1) or claim (2), characterized in that: