CN1039780C - Ultrasonic surgical instrument - Google Patents

Abstract

The invention relates to an ultrasonic surgical instrument which consists of a handle and a main machine. The handle comprises a cutter, an amplitude transformer, a level changer, a flushing pipe, a suction pipe, a cable and the like, and the ultrasonic waves are transmitted to various surgical cutters through the transducer and the amplitude transformer and act on biological tissues. The main machine is the electrical part of the ultrasonic surgical instrument and comprises an ultrasonic generator, a power amplifier, a manual and foot brake control system and a dynamic fault diagnosis and automatic cut-off system. Under the control of microcomputer, the frequency generator generates ultrasonic pulse of small signal, which is amplified and sent to the handle. The surgical instrument has the advantages of selective fracture, small injury, high precision, hemostasis and the like.

Description

The invention relates to an ultrasonic surgical instrument, which belongs to the technical field of medical instruments.

Surgery is an important means of clinical medicine. With the continuous development of this field, the development of surgical knife technology is changing with each passing day. Before laser, electronics and other technologies were applied to the field of surgery, the mechanical scalpel dominated for a long time. It is small in size and sharp in cutting, but it also has disadvantages, such as it cannot be used for special surgical operations, and the amount of blood loss during the operation is large, etc. , these disadvantages limit the scope of application of the mechanical scalpel. With the development of laser and electronic technology, various types of surgical scalpels, such as high-frequency electric knife, laser knife, microwave knife and argon knife, have appeared successively. Compared with traditional mechanical knife, they have more obvious hemostatic effect, and clinical application The scope has also been greatly expanded, such as the removal of some internal organs and so on. The structure of the high-frequency electric knife is shown in Figure 1. Its working principle is: the high-frequency pulse generator generates a high-frequency spike, which is a low-voltage, high-current signal, which is sent to the main electrode on the handle through the cable, and uses the local thermal effect generated by the high-frequency pulse sent by the main electrode The soft tissue of the human body is cut, and the auxiliary electrode is also in contact with the surface of the human body during work. High-frequency electrotome has obvious hemostasis effect, but with the burning of soft tissue, there is a pungent smell, and the recovery after incision surgery is also slow. In addition, the cutting speed of high-frequency electrotome is slow, and it can only cut soft tissue. Hard tissues such as cartilage, skull, femur, etc. cannot be cut. Chinese patent 92109992.4 discloses "an ultrasonic surgical device", which is used for visceral suction. Its working principle is to add ultrasonic vibration to the negative pressure suction device, and after the lesion tissue is crushed by ultrasonic energy, it is sucked away. The shortcoming of this device is: 1, function is single, and each host computer can only be equipped with the cutting tool of a kind of function (being negative pressure suction function); The required prestress, the screw device is not easy to make the ceramics evenly stressed, and the prestress size is not easy to adjust; 3, the control part is not automated.

The purpose of the present invention is to design an ultrasonic surgical instrument, improve the structure of the existing ultrasonic instrument, realize automatic control of the operation process, and equip five different cutting tools on the same host, so that it is suitable for general surgery, orthopedics, neurosurgery and Obstetrics and Gynecology etc. In surgical operations, using the characteristics that ultrasonic waves can propagate in elastic media, ultrasonic vibrations are added to specialized surgical instruments, so that ultrasonic waves can act on biological tissues through surgical tools, mainly through the strong acceleration and cavitation effect generated by ultrasonic vibrations , cutting or fragmenting biological tissue.

The ultrasonic surgical instrument designed by the present invention is composed of a handle and a host. The handle consists of cutter, horn, transducer, flushing tube, suction tube and cable. The handle is connected with the host through a cable. The transducer is a cylindrical structure with piezoelectric ceramics sandwiched in the middle and installed in a prestressed sleeve. The piezoelectric ceramics are connected to the handle cable through electrode leads. The transducer is connected with the horn by screws. The cutter is glued to the end of the horn. The flushing pipe and the suction pipe are respectively fixed on the handle shell, and their ends are aligned with the cutter. The host has its ends flush with the cutter. The host is the ultrasonic source and control part of the handle, which is composed of an ultrasonic generating circuit, a power amplifier circuit, and a handle control circuit. The ultrasonic generation circuit includes D/A conversion module U ₄ , single-chip microcomputer U ₁ that controls the D/A module to generate analog voltage signals, operational amplifiers U ₅ , U ₆ and U ₇ for operationally amplifying voltage signals, and voltage-frequency conversion Module U ₈ , pin register U ₂ , and extended off-chip storage module U ₃ . The power amplifying circuit includes transistor T ₁ for stimulating and amplifying small-signal ultrasonic waves, transistor T ₂ for amplifying the signal twice, coupling transformer TRAN for coupling and transforming the signal, and transistor T for providing constant current to the power transistor of the excitation stage ₃ . The handle control circuit includes keys S ₁ -S ₆ for respectively controlling flushing, suction, manual, automatic, cut-off, and foot switch, and NAND gates IC ₁ : A, IC ₁ : B, and IC ₂ : for multi-channel selection. A and IC ₂ : B, D flip-flop IC ₃ for shaping the selected control signal: A and IC ₃ : B and IC ₄ : A, IC ₄ : B, driving circuit IC ₅ for driving the relay: A , IC ₅ : B, IC ₅ : C and IC ₅ : D, triode amplifier tubes DG ₁ , DG ₂ and DG ₃ and relays J ₁ , J ₂ and J ₃ for performing control actions.

The invention has the unique advantages of selective fragmentation, less damage, high precision, hemostasis, etc., especially selective fragmentation can protect blood vessels and nerves from damage. It can be applied to small and medium-power brain and eye surgery, resection of visceral tumors, high-power sawing and drilling operations, etc. The application range of ultrasonic scalpels exceeds the aforementioned surgical scalpels.

Description of drawings:

Fig. 1 is a principle block diagram of the prior art high-frequency electrosurgical unit.

Fig. 2 is a schematic block diagram of the ultrasonic surgical instrument of the present invention.

Fig. 3 is a schematic structural view of the handle in the ultrasonic surgical instrument.

Figure 4-1 to Figure 4-5 are five different structural diagrams of the knife in the handle.

Fig. 5 is the ultrasonic generating circuit (1).

Fig. 6 is the ultrasonic generator circuit (2).

Figure 7 is a power amplifier circuit.

Figure 8 is the handle control circuit.

Below in conjunction with accompanying drawing, introduce the content of the present invention in detail. Fig. 2 is a structural schematic diagram of the handle in the surgical instrument of the present invention. In the figure, 1 is the tool, 2 is the horn, 3 is the screw, 4 is the prestressed sleeve, 5 is the piezoelectric ceramic, 6 is the transducer, 7 is the electrode lead, 8 is the cable, 9 is the handle shell, 10 is a suction outlet, 11 is a flushing inlet, 12 is a horn shell, 13 is a suction pipe, and 14 is a flushing pipe.

The working process of the handle can be briefly described as:

The transducer uses the piezoelectric effect of piezoelectric ceramics to convert electrical signals into ultrasonic mechanical vibrations of the same frequency. After being amplified by the horn and ultrasonic surgical knives, it radiates ultrasonic waves of a certain power for human surgery.

The structural diagram of the handle is shown in Figure 3. Among them, the quality of the piezoelectric transducer directly affects the technical indicators of the entire instrument. The piezoelectric transducer 6 adopts a sandwich structure of piezoelectric ceramics, with piezoelectric ceramics 5 in the middle, and the whole transducer uses a prestressed sleeve 4 to fine-tune the size of the prestress added to the piezoelectric ceramic stack. Ventilation and heat dissipation holes, which also serve as electrode lead holes.

The amplitude of the output of the transducer is usually small, usually more than ten microns. In order to make the ultrasonic radiation head produce a larger amplitude, and at the same time, in order to effectively transmit the output power of the transducer to the radiation head to achieve acoustic matching, generally in Add a horn between the two. As shown in the accompanying drawing 3, the horn 2 adopts two-stage amplitude amplification, and the structure in which the horn and the transducer are tightly connected by screws 3 is adopted. Sleeve 12 is also installed outside the horn.

On the handle shell 9, a suction pipe 13 and a flushing pipe 14 are fixed, and these two pipes have a suction port 10 and a flushing port 11 respectively, and are connected to the flushing suction device.

As accompanying drawing 3, scalpel 1 is housed at the front end of horn.

The ultrasonic vibration system composed of a transducer, a horn and an ultrasonic surgical tool produces the maximum amplitude at the end of the ultrasonic surgical tool and radiates ultrasonic waves of a certain power. According to different uses, the end of the ultrasonic surgical knife can be processed into various shapes, such as serrated for bone sawing, sharp blade for cutting tissue, cylindrical for crushing tumors, and so on. Ultrasonic surgical knives of different shapes have different flow directions and different effects of the radiated acoustic microflow, which can meet various needs.

As shown in Figure 4-1 to Figure 4-5, the structural diagrams of five kinds of surgical knives are given, which are respectively a cutting knife, a saw knife, a cleaning knife, a suction head, and a puncture rod.

The ultrasonic surgical instrument of the present invention, the ultrasonic source and the handle control part mainly include:

The ultrasonic surgical instrument of the present invention mainly consists of two parts, namely a host and a handle. See attached drawing 2 for the general principle block diagram.

The following are introduced respectively:

(1) Host

The host is the ultrasonic source and control part of the ultrasonic surgical instrument, mainly including ①ultrasonic generation circuit; ②power amplifier circuit; ③manual and foot switch control circuit; ④dynamic fault diagnosis and automatic cut-off circuit.

The working process of the host part can be briefly described as:

Under the control of the microcomputer, the ultrasonic generator generates ultrasonic pulses of small signals, which are amplified by a high-power amplifier and sent to the handle.

Each part is described below.

1. Ultrasonic generating circuit:

The mechanical quality factor (Q value) of the piezoelectric transducer is relatively high, so it is necessary to use a high-precision voltage-frequency conversion module to generate an ultrasonic source with high stability, high precision, and high output spectrum purity.

The circuit principle of this part is shown in Figure 5 and Figure 6: MCU module 8098 (U ₁ ), its peripheral circuit includes latch 74ALS373 (U ₂ ), extended off-chip storage module 764 (U ₃ ), etc. MCU module 8098 controls D After being amplified by the /A conversion module DAC1210 and the operational amplifier OP07 (U ₇ ), it is sent to the high-precision voltage-frequency conversion module LM314 (U ₈ ) to generate ultrasonic signals.

2. Power amplifier circuit:

As shown in Figure 7, the power amplifier circuit adopts two stages: the excitation stage and the amplification stage, and is equipped with a constant current source circuit and a protection circuit. The amplifier stage adopts Class A power amplifier.

The small-signal ultrasonic wave sent from the ultrasonic generator is firstly amplified by the power transistor B940 (T ₁ ) through excitation, and then goes to the amplifier stage power transistor 3DA810 (T ₂ ) for secondary amplification to become a high-power ultrasonic signal, and finally passes through the coupling transformer TRAN output, which applies the high-power ultrasonic signal to the piezoelectric transducer (inside the handle). The transistor B507 (T ₃ ) of the constant current source circuit provides constant current for the power transistor B904 (T ₁ ) of the excitation stage, so that the power amplifier works stably.

3. Manual and foot brake control system:

In order to facilitate the operation, the microcomputer is used to realize the control of the power amplifier on and off by manual and foot switch, so as to control the working state of the instrument.

For flushing control, see "IRRIGA-TION" in the electrical schematic diagram in Figure 8

For suction control, see "SUCTION" in the electrical schematic diagram in Figure 8

For manual control, see "MANU" in the electrical schematic diagram in Figure 8

For automatic control, see "AUTO" in the electrical schematic diagram in Figure 8

For foot brake control, see "FOOTBREAK" in the electrical schematic diagram in Figure 8

See "MANU" in the electrical schematic diagram in Figure 8 for automatic cut-off control

4. Dynamic fault diagnosis and automatic cut-off system:

When the instrument is in abnormal working state, such as handle leakage, power amplifier output too high voltage, power supply output inrush current, the microcomputer can automatically identify the abnormal fault, and cut off the power immediately to ensure the safety of the human body and the instrument.

See "AUTOBREAK" in the schematic diagram of Figure 8 for automatic cut-off control

As shown in the schematic diagram of Figure 8, the six buttons S ₁ -S ₆ in the above two parts all pass through the NAND gate 74LS21, the D flip-flop 74LS74, and the driving circuit 7404. After being amplified by the triode 2N5551, they control the opening and closing of the relay to Various controls are realized.

Claims (2)

1. ultra-sonic surgical aspirator, this surgery apparatus is made up of handle and main frame two parts; Described handle is made up of cutter, horn, transducer, syringe pipe, draft tube and cable, handle joins by cable and main frame, it is characterized in that wherein said transducer is a core structure, the centre accompanies piezoelectric ceramics, and is contained in together in the prestressing force sleeve, and piezoelectric ceramics joins by contact conductor and handle cable, transducer is connected with horn by screw, cutter is bonded in the horn end, and syringe pipe and draft tube are separately fixed on the handle casing, and its end is mutually neat with cutter; Described main frame is the supersonic source and the control section of handle, is made up of ultrasonic generation circuit, power amplification circuit, handle control circuit, and ultrasonic generation circuit wherein comprises D/A modular converter U ₄, control D/A module produces the single-chip microcomputer U of analog voltage signal ₁, voltage signal is carried out the operational amplifier U that computing is amplified ₅, U ₆And U ₇, voltage-frequency translation module U ₈And latch U ₂, expansion sheet external memory module U ₃, power amplification circuit wherein comprises the transistor T that the small-signal ultrasound wave is encouraged amplification ₁, transistor T that the signal secondary is amplified ₂, to signal be coupled the coupling transformer TRAN of transformation, the transistor T of constant current is provided for the drive(r) stage power transistor ₃, handle control circuit wherein comprises respectively the control flushing, attracts, manually, automatically, the button S of cut-out, backpedalling brake ₁-S ₆, be used for the NAND gate IC that multichannel is selected ₁: A, IC ₁: B, IC ₂: A and IC ₂: B, be used for d type flip flop IC to the control signal shaping of selecting ₃: A and IC ₃: B and IC ₄: A, IC ₄: B drive circuit IC ₅: A, IC ₅: B, IC ₅: C and IC ₅: D, three utmost point amplifier tube DG ₁, DG ₂And DG ₃And the relay J that is used to carry out control action ₁, J ₂And J ₃

2. ultra-sonic surgical aspirator as claimed in claim 1 is characterized in that wherein said cutter is cutting knife, saw cutter, cleans cutter, attracts any in head and the puncturing lever.

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