JPS5858034A - Method and apparatus for oscillating ultrasonic wave - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a novel ultrasonic oscillation method and apparatus for surgical operations.

For surgeons, scalpels are used to incise living tissue, but like electric scalpels and laser scalpels, they also cauterize cellular tissues and blood vessels such as capillaries, and also perform incision and hemostasis. It is a surgical tool suitable for surgical fields that perform incision and hemostasis at the same time. However, since these surgical tools cut blood vessels and nerves at the same time as incising tissue, they are not suitable for surgical sites where a large number of blood vessels and nerves are concentrated, such as the liver and armpit tissues, or other surgical sites. However, in surgeries where you want to preserve blood vessels and nerves, electric scalpels are used.
It is quite difficult to use a laser scalpel, and people rely on conventionally used stainless steel blades, steel blades, Mosquido, etc.

The present invention provides a novel ultrasonic scalpel that can crush and remove cells to be removed without damaging blood vessels or nerves at such surgical sites, that is, surgical sites where blood vessels and nerves are concentrated. It provides:

Surgical instruments that utilize the ability to cut or crush tissues using ultrasonic waves include instruments for cutting bones and joints in the orthopedic and general surgery fields, cataract surgical instruments in the ophthalmology field, and ultrasonic instruments for removing tartar in the dental field. Sonic surgical instruments and the like have been put into practical use. However, these ultrasonic surgical tools do not produce the amplitude and power of ultrasonic vibrations sufficient to crush tissue to a certain extent, and are used as specialized surgical tools for extremely limited surgical fields. .

The ultrasonic scalpel according to the present invention has a novel circuit for an ultrasonic scalpel that can generate the amplitude and power of ultrasonic vibration that can exhibit sufficient tissue crushing ability in a wide range of areas of living tissues, a horn serving as a scalpel part, and a surgical horn. System 3 for cleaning around the site, emulsifying crushed cell debris, and removing emulsified cell debris by suction
The present invention provides a novel ultrasonic scalpel consisting of several elements.

The details will be explained below based on the drawings.

The ultrasonic oscillator used in the ultrasonic scalpel of the present invention includes a power supply section (1), an amplification section (2), and a matching section (3) shown in Fig. 1.
, a feedback section (4), and an ultrasonic transducer (5) that converts electrical vibration energy into mechanical vibration energy. The details of these basic circuits will be explained in detail with reference to FIG. The power supply section (1) includes an inrush current mitigation circuit (7),
It is composed of a rectifier circuit (8) and a smoothing circuit (9). It is supplied with ACi oov or an appropriate AC voltage from a commercial AC power supply (6) and is connected to the inrush current mitigation circuit (n).

This inrush current mitigation circuit (7) is a rectifier circuit (8) which is an A-D conversion circuit that converts the excessive current flowing when power is turned on to the oscillation circuit of this ultrasonic scalpel from AC power to DC power. This inrush current mitigation circuit (7) is designed to protect and stabilize the power supply circuit by adopting this inrush current mitigation circuit (7).

In addition, if the ripple rate of pulsating current is large in the DC waveform obtained by the rectifier circuit (8), the ultrasonic transducer (Xun and Horn (10)
Since the mechanical vibration system consisting of the following is unstable, a smoothing circuit (9) is provided for the purpose of reducing this ripple rate. This smoothing circuit (9) allows the horn (10
) can provide extremely stable ultrasonic vibrations at the tip.

The amplifier section (2) includes a power amplifier circuit 01), a starting shock-sum circuit (12), a spike wave removal circuit α3), and an amplitude adjustment circuit 04). The power amplifier circuit α1)2: uses a low-loss circuit system that enables continuous oscillation without cooling. Generally, when generating high power with an ultrasonic oscillator circuit, at the start of oscillation, the power amplification element and the ultrasonic transducer (5) receive an electrical shock, often leading to performance deterioration or destruction; There are many cases where the mechanical vibration system consisting of the converter (5) and the horn α0) has difficulty in starting up when it is under load. ) to protect and stabilize the power amplifier circuit (11) and the ultrasonic transducer (1), and to make it extremely easy to start up the horn (10), which is the ultrasonic scalpel part, from a loaded state. Moreover, the power amplifier circuit 01) generates a spike wave that is superimposed on the square wave that is the voltage waveform of the output of the power amplifier circuit (11), but this spike wave is more than twice as large as the square wave. This tends to cause characteristic deterioration or destruction of the amplification element and the ultrasonic transducer (5), and the present invention provides a spike wave removal circuit (13) after the power amplification circuit (11). removing the spike waves and protecting the amplification element and ultrasonic transducer (5) in the power amplification circuit α1);
This made stabilization possible. Furthermore, an amplitude adjustment circuit 04) is provided to enable continuous changes in the vibration amplitude of the tip of the horn (10), that is, the tip of the scalpel, making it easy to adjust the degree of crushing according to the condition of the surgical site.

The matching section (3) of the oscillator for an ultrasonic scalpel of the present invention includes the amplitude level setting circuit (16), the return signal detection circuit (17), and the power applied to the ultrasonic transducer (1) of the matching circuit 0. The power detection section (18) detects the amplitude of the horn (10), and the amplitude detection section (19) displays the amplitude of the horn (10). The matching circuit α5) allows electrical power to be input to the ultrasonic transducer (5) with low loss even when the load on the tip of the horn (10), that is, the tip of the knife increases, without reducing the vibration amplitude of the tip of the knife. This matching circuit allows the power of ultrasonic vibration to be maintained against changes in the operating field load. Moreover, in the present invention, it is important to optimize the drive amplitude in order to stably operate the ultrasonic transducer (5), and the amplitude level setting circuit (16) allows the ultrasonic transducer (5) to have low loss and Efforts are being made to stabilize the situation. Feedback signal detection circuit (17)
is a circuit that detects the resonant frequency and amplitude of the mechanical vibration system that change depending on the load conditions and temperature applied to the tip of the horn 00), and feeds this signal back to the pre-amplification stage, that is, the power amplifier circuit (11). This enables constant amplitude control and automatic frequency tracking.

The feedback section (4) of the oscillator for ultrasonic scalpels of the present invention includes a feedback signal Q adjustment circuit (20) and a feedback signal filter circuit (21).
). The resonance frequency and amplitude of the mechanical vibration system detected by the feedback signal detection circuit (17) are expressed as a feedback signal Q.
Adjustment circuit (20) and feedback signal filter circuit (21)
The power is fed back to the power amplifier circuit (11) via the power amplifier circuit (11).

The feedback signal Q adjustment circuit (20) needs to increase the Q of the feedback circuit at the start of oscillation in order to sharpen the rise of ultrasonic oscillation, but after this ultrasonic oscillation enters a steady state, the horn In order to maintain stable vibration against load fluctuations (10), the lower the Q of the feedback circuit, the better, and by automatically adjusting the Q of this feedback circuit, the transient state and steady state of vibration can be stabilized. They have a role to play. On the other hand, a mechanical vibration system consisting of an ultrasonic transducer (5) and a horn (10) often has several spurious frequencies in addition to the main resonance frequency, and these spurious frequencies are In the present invention, a feedback signal filter circuit (21) is employed for the purpose of removing this spurious frequency, thereby making it possible to stabilize the ultrasonic scalpel.

Next, one embodiment of the handpiece portion of the ultrasonic scalpel of the present invention will be described in detail with reference to FIGS. 3 and 4.

FIG. 3 is an overall view of the handpiece portion of the ultrasonic scalpel according to the present invention. The handpiece part is the matching part of the ultrasonic oscillation part (
3), the cable (22) connected to the connector (
23), grip part 04), protection tube (25), horn α0) which is an ultrasonic scalpel part, irrigation tube (26) for supplying physiological saline etc. to the surgical site, suctioning liquid substances etc. from the surgical site It mainly consists of a suction pipe (27) for

The connecting pipe C28) is a pipe that mechanically connects the grip part (24) and the protective tube (2) with a screw or the like.

Grip part (24), connection tube (28'), protection tube (20
In order to reduce the overall weight of the hend bead and make it easier for the operator to handle it, it is made of light and corrosion-resistant metals such as aluminum and duralumin, or high-strength synthetic resins such as phenolic resin and ABS resin. It is preferable to configure The horn 00) that serves as the ultrasonic scalpel part is made of a material such as ultra-super duralumin or titanium alloy that has good transmission of high-frequency mechanical vibrations and is strong against breakage. A suction hole (29) is provided for suctioning and removing blood, physiological saline for washing, cell fragments crushed by the horn (10), etc., and this suction hole (29) is located on the outside of the protective tube (25). The suction pipe (27) is connected to the suction pipe (27) through a pipe (30) connected in an appropriate manner to the suction pipe (27). A suction nipple (31) is connected to the other end of the suction pipe (27) by an appropriate method such as brazing or argon welding. This suction nipple (31)
Although not shown in the figure, flexible materials and shapes that can withstand the suction pressure removed by the suction device, such as vinyl chloride or silicone resin, are connected to a suction device such as a vacuum pump through a trap such as a glass bottle. Connect your computer.

The irrigation pipe (26) is for supplying cleaning fluid such as physiological saline to the surgical site.
It is desirable to have an open end near the tip of the horn 0 and to arrange it close to the horn 0 without touching it. If it comes into contact with the horn (10), the irrigation pipe (26) may be damaged because the horn (10) vibrates ultrasonically, and if it is too far away from the horn (10), it may cause microsurges in brain surgery, etc. In some cases, this irrigation pipe (26) may become a hindrance. The irrigation pipe (26) is fixed or connected to the pipe pipe (30) in an appropriate manner to prevent contact with the horn (10) or to prevent it from moving too far away from the horn (10). An irrigation nipple (32) is connected to the other end of the irrigation pipe (26) by an appropriate method such as brazing or argon welding. This irrigation nipple (32) is supplied with washing water such as vinyl chloride, silicone resin, etc. (not shown) in a washing water container such as physiological saline by a roller type pump such as a pellister pump (not shown). Connect a flexible tube that is medically safe and made of a material and shape that can withstand the stress of a roller-type pump.

The pipe stopper (33) holds the suction pipe (27) and the irrigation pipe (26) in the grip portion (24).
) is a stopper to be fixed to the Suction pipe (27), irrigation pipe (26), suction nipple (31),
Irrigation nipple (32), pipe play 1 India (
The material of No. 3 and the pipe stopper (33) is preferably a corrosion-resistant and elution-resistant material such as stainless steel.

Furthermore, the internal structure of the handpiece part of the ultrasonic scalpel of the present invention,
The vibration characteristics etc. will be explained in detail based on Figure @4.

The aforementioned ultrasonic transducer (5) includes an electrostrictive vibrator (34),
A backing plate (3) and a front plate (36) made of a high tensile strength metal material such as ultra-super duralumin or hard aluminum alloy are provided at the front and rear of the electrostrictive vibrator (34), and on the left and right sides in FIG. 35), electrostrictive vibrator (34), and front plate (
36) are connected and fixed to each other by bolts made of high-strength metal material (not shown);
(Bolt-clamped melangepan type vibrator) type vibrator structure. The front plate (36) and the horn (10) that becomes the ultrasonic scalpel part
) are connected and fixed with set screws made of high-tensile metal material. Electrostrictive vibrator (PZT (lead zirconate titanate) is preferable for the three types, and its related frequency is IMHz ~ 10
0MHz% m*L< is lOMHz ~20MH2fi
Good degree. The backing plate (35) and front plate (36) attached to both ends of the electrostrictive vibrator (34) are composed of the backing plate (3), the electrostrictive vibrator (34), the front plate (30), and the horn (10). The frequency of the ultrasonic transducer (5) is 20KHz.
~40KHz, Desired*1. <)! , 23KH2~28K
Hz1: Determine the diameter and length so that.

The shape of the horn α0) is the tip part (38) of the horn αO).
Generally speaking, the amplitude of the tip (38) of the horn (10) is determined by the cross-sectional area of the root (39) of the horn (10) and the tip of the horn (10). (3
8) is inversely proportional to the ratio of cross-sectional areas. The amplitude of the tip (38) of the horn (10) used in the ultrasonic scalpel of the present invention is 5
The thickness is preferably 0 to 250 microns, preferably 100 to 150 microns. The material of the horn (10) is preferably a high tensile strength metal material, preferably a titanium alloy.

The ultrasonic transducer (5) used as the ultrasonic scalpel of the present invention using an electrostrictive vibrator (34) made of PZT includes other vibrators,
For example, in the case of a magnetostrictive vibrator using ferrite, it is strong against compression in the axial direction, but weak against elongation, and as a result, it is not possible to obtain a high amplitude. Furthermore, in the case of a nickel-based magnetostrictive vibrator, compared to the electrostrictive vibrator of the present invention, it has poor security resistance, and if a large load is applied to the tip of the horn, there is a risk of damage. The target Q has to be lower than that of an electrostrictive oscillator, and as a result, electricity loss increases and the oscillator generates heat.This generated heat must be removed by cooling means such as water. Damaged vibrator? In the ultrasonic scalpel of the ultrasonic transducer type using the electrostrictive vibrator of the present invention, the tip (38) of the horn (10)
It has the advantage of being strong against the load applied to it, has a high mechanical Q, has low discharge loss, generates little heat from the vibrator, and can exhibit sufficient durability without using cooling means, and is similar to ultrasonic scalpels. It is ideal for applications that require the highest reliability.

Next, an ultrasonic transducer (5) using the electrostrictive vibrator of the present invention
The vibration characteristics will be explained based on FIG.

The graph shown in the upper part of Fig. 4 shows the ultrasonic transducer (5)
It is the amplitude pattern in the axial direction of each part of the electrostrictive vibrator (
The amplitude is zero at the axial center of the horn (10
) The amplitude is zero near the aperture start part (40) of the horn (10), and the area between the electrostrictive vibrator (34) and the aperture start part (40) of the horn (10) has an arc shape with a peak near the set screw (37). Also, the left end (41) of the backing plate (35) and the electrostrictive vibrator (34)
The space between the backing plate (three left ends (41) has a half-arc shape with the maximum amplitude). The tip (38) of the horn (10) has a semi-arc shape with the maximum amplitude.As mentioned above, the amplitude of the tip (38) of the horn (10) is one of the characteristics of the ultrasonic scalpel. 10) The root part (
39) and the cross-sectional area of the tip (38) of the horn (10), so this cross-sectional area can be changed depending on the area to be treated with this ultrasonic scalpel, the degree of surgery, etc., and various amplitudes can be adjusted. Obtain the shape of the horn.

Next, another embodiment of the ultrasonic transducer for an ultrasonic scalpel according to the present invention will be described with reference to FIGS. 5 and 3.

As mentioned above, since the transducer of the ultrasonic transducer section of the ultrasonic scalpel according to the present invention uses an electrostrictive vibrator, the electric loss of the vibrator is small, and as a result, the vibrator section generates little heat. However, it is clear that the durability of the vibrator can be improved to a certain degree if the heat generated in the vibrator section can be further removed.

Therefore, as shown in Fig. 5, a suction hole (42) is provided along the entire length of the axis of the ultrasonic transducer (5), and an irrigation pipe C26) is set in the same manner as the irrigation pipe (26) shown in Fig. 3. The hollow electrostrictive vibrator (43) can be cooled by sucking cleansing water such as physiological saline supplied to the surgical site through the suction hole (42). Set screw part (4 units) and hollow electrostrictive vibrator (4 units)
Although airtightness with the suction hole (42) in 3) is not shown,
Airtightness may be achieved using an appropriate sealing method such as Q-ying or Teflon sealing tape. In addition, in Fig. 5, the suction hole (42) is provided over the entire length of the ultrasonic transducer (5), but if it is on the backing plate (45), it is provided in a direction perpendicular to the axis of the ultrasonic transducer (5). An outlet for the suction hole may be provided.

As described in detail above, the ultrasonic oscillation method and device according to the present invention are extremely useful inventions that exhibit sufficient functions as ultrasonic scalpels for surgical operations.

[Brief explanation of the drawing]

FIG. 1 is a basic block diagram of the ultrasonic scalpel according to the present invention.
Figure 2 is a detailed diagram of the basic block diagram shown in Figure 1;
The figure shows one embodiment of the handpiece section, FIG. 4 shows one embodiment of the ultrasonic transducer and its vibration characteristics, and FIG. 5 shows another embodiment of the ultrasonic transducer.

Claims (4)

[Claims] (1) In an ultrasonic oscillator circuit, an inrush current mitigation circuit for overcurrent prevention is provided at the front stage of a rectifier circuit that converts AC power into DC power, and a smoothing circuit for ripple rate reduction is provided at the rear stage of the rectifier circuit. After connecting the power that has passed through the circuit to a power amplification circuit and inputting the electrical signal from the power amplification circuit to a spike wave removal circuit, the electrical power to the ultrasonic transducer is reduced to low loss when the load on the ultrasonic transducer increases. The electrical signal that has passed through the matching circuit is input to an amplitude level setting circuit that ensures low loss and stabilization of the ultrasonic transducer, and then the return signal is connected to the ultrasonic transducer. A feedback signal from the feedback signal detection circuit is fed back to the power amplifier circuit via a feedback signal Q adjustment circuit and a feedback signal filter circuit for removing spurious frequencies, and a feedback signal from the feedback signal detection circuit is connected to the power amplifier circuit. An ultrasonic oscillation method for an electrostrictive vibrator that connects an amplitude adjustment circuit of a sound wave transducer and a starting shock mitigation circuit that alleviates the electrical shock at the start of oscillation. (2) In the ultrasonic oscillation circuit, an inrush current circuit (7) is provided before the rectifier circuit (8), and a smoothing circuit (CJ) is provided after the rectifier circuit (8).
The smoothing circuit (9) is connected to the power amplifier circuit 01), the amplitude adjustment circuit (14) and the starting shock mitigation circuit are connected to the power amplifier circuit (11), and the electric signal output from the power amplifier circuit (11) is connected to the power amplifier circuit (11). Spike wave removal circuit 03), matching circuit α5)
, amplitude level setting circuit (16) and feedback signal detection circuit α
An ultrasonic transducer (5) consisting of an electrostrictive vibrator is connected to the feedback signal detection circuit α power, and from the feedback signal detector 07) to the power amplification circuit (11). During feedback C: Ultrasonic oscillator provided with a feedback signal side adjustment circuit 20) and a feedback signal filter circuit (21). (3) In the ultrasonic oscillator according to claim (2), a horn (
A suction hole (38) is provided inside the horn (10), and an irrigation pipe (26) is provided at a position close to the horn (10).
) is installed. (4) In the ultrasonic oscillator according to claim (3), a hollow electrostrictive vibrator (43) is used, and the suction hole (42) is connected from the horn (42) to the backing plate (45). An ultrasonic oscillator characterized in that it can be placed at any arbitrary position.