US2835254A - Device for performing surgical incisions by electronic energy - Google Patents

Description

y 0, 1958 w. A. COLES 2,835,254

DEVICE FOR PERFORMING SURGICAL INCISIONS BY ELECTRONIC ENERGY Filed Dec. 17. 1953 INVENTO l f z'iZa'am A. 6'4; 66

ATTORNEY S.

United States Patent DEVICE FOR PERFORMING SURGICAL IN CISIONS BY ELECTRQNIC ENERGY William A. Coles, Upper Darby, Pa. Application December 17, 1953, Serial N0. 398,741 1 Claim. (Cl. 128--303.14)

The present invention relates to methods of making incisions in the body in live tissue without shock and without tissue damage which will interfere with normal healing, and to apparatus for this purpose of the character generally known in the trade as an electric or electronic cautery, knife, scalpel or electrotome.

A purpose of the invention is to minimize tissue damage in making incisions, and thus produce incisions in surgery which will heal rapidly and will not cause a necromic effect along the edge of the incision.

A further purpose is to minimize all nervous reaction of the patient which may contribute to shock.

A further purpose is to insure the introduction of a maximum of electronic energy at the point of incision in a minimum of time, and at a frequency which will be most favorable from the standpoint of rapid recovery.

A further purpose is to produce a uni-directional current from an alternating current, to convert the uni-directional current into a full wave pulsing current at a frequency between. 2.75 and 3.25 megacycles per second, and to pass the high frequency current thus produced into the body of the patient at a terminal provided with an incision instrument, connecting another terminal to a dispersive contact.

A further purpose is to produce a uni-directional current by rectifying an alternating current, to produce a high frequency current of regulated frequency from the uni-directional current, to pass the high frequency current through a resonant tank circuit, to conduct current to the patient from the inductive element of the tank circuit and to employ capacitative blocking between each contact applied to the patient and the tank circuit, and also preferably between the source of high frequency current and the tank.

A further purpose is to energize the cathodes of the rectifier and transmitter tubes by a pro-action switch and to produce operation of the electronic cautery by a final action switch which energizes the enodes of the rectifier tubes.

A further purpose appears in the specification and in the claims.

In the drawing I have chosen to illustrate only one of the numerous embodiments in which my invention may appear, selecting the forms shown from the standpoints of convenience in illustration, satisfactory operation and clear demonstration of the principles involved.

The drawing shows on electric circuit diagram useful in explaining the invention.

In the prior art s'o-called electrical knives and cauteries have been produced, which have been used with varying degrees of success in surgery, such as brain surgery and prostatic surgery. It was used in these operations largely for hemostatic purposes, and there was a substantail amount of tissue destruction and necrosia incidental to the use of the device. The present inventor has "ice.

endeavoured to minimize necrosisand tissue destruction so as to make an electronic cautery which can be used in all types of surgery and not merely those in which hemostatic action is desired. Thus, by the equipment of the present invention it is possible to remove sections of tissue for biopsy and to secure representative samples of tissue sections which will indicate the condition of the body from which the sample is taken.

The electronic cautery of the present invention is an improved device which is designed'to enable the surgeon to make any desired incision without exerting pressure which deforms the tissue, and with assurance that the incision will heal normally and without any untoward incidents due to the presence of the electric discharge. Great care has been used in the development of the present mechanism to operate at a frequency which is most conducive to benign surgery, and to secure most efiective blocking to cut off stray currents and limit normal currents to safe limits. On the other hand the device of the invention can be adjusted to give hemostatic effects if desired.

In accordance with the invention, a uni-directional current is obtained from a full-wave rectifier, and the output of the full wave rectifier is converted by a transmitter tube fitted to a tank circuit to create a frequency of from 2.75 to 3.25 megacycles. Blocking is introduced between the transmitter tube and the tank circuit. The induetive element of the tank circuit discharges to electrode terminals at one end through blocking capacitors and to a dispersive contact at the other end through a blocking capacitor. One of the electrode terminals is provided with additional blocking capacitance and both are preferably provided .with variable blocking capacitance.

The mechanism is arranged so that the cathodes of all of the vacuum tubes can be energized in advance, and the final operation of the electronic cautery is produced by energizing the anodes of the rectifier tubes.

Considering now the drawing in detail, the circuit comprises a rectifier 20, a transmitter tube 2i and a tank circuit loop 22, to be more fully described in detail.

A source of alternating current suitably at commercial frequency, desirably volts at 60 cycles, is connected to input terminals 23 and 24. These terminals connect through a pre-action switch 25 to the primary of a rectifier filament transformer 26 and to the primary of the transmitter tube filament transformer 27. The secondary of the transformer 26 is connected to the cathode of half-wave gas-filled rectifier tubes 28 and 30, whose cathodes are opposed as well-known. A mid-tap 31 from the secondary of the transformer 26 is connected to one side of the anode choke 32, the other side of which is connected to the anode of the transmitter tube 21, and is also connected through anode biasing resistor 33 in parallel with capacitor 34 to ground, to reduce ripple;

The secondary of the transmitter tube filament transformer 27 is connected to the cathode of the transmitter tube 21, and the mid-tap v35 is grounded, and capacitors 36 and 37 are connected between the opposite terminals of the secondary of the transformer 27 and ground to eliminate ripple.

The terminals 23 and 24 are also connected to the primary of the anode transformer 38 through normally open relay 39 whose heater coil 39' is across the second ary of the transformer 27 and the secondary of this transformer is connected to the anodes of the half wave rectifier tubes 28 and 30, mid-tap 40 being grounded. Relay 39 is a thermal time delay relay which assures that the cathodes of rectifier tubes 28 and 3b are heated before voltage is applied to the anodes, thus assuring damage will not be done to the tubes or other circuit components.

The output ofthe rectifier. is connected through the choke.32 to the anode, of the transmitter. tube as already. explained. The control grid of the. transmitter. tube is grounded through choke 41 and grid biasingresistor 42, so that energy passes to the grid through ground.- The anode. of'the. transmitter tube 21 is connected through auxiliary blocking. capacitor 43" to. one. side of the tank circuit loop 22, which includes a capacitor and an inductor 45 in parallel resonance; The control grid of the transmitter tube is connected through auxiliary blocking capacitor 46 to" the opposite side of the tank circuit loop 22.

Theoutputfrornthe electroniccautery is taken oil fromv one side of the inductive reactance45 througha lea-d whichpassesto an electrode terminal 47 and an el ctrode terminal 48 inpa'rallel. Thelead46'. is connected tothe inductivereactance; near the. end connected: to the anode (plate) of tube21;.and. by. adjusting the:tap closer to the end of thereactance. connected to, the anode, the. severity of the cautery cambe increased. Both of the electrode terminals-4'7 and48.- are. equipped to receivean electronic cautery implement as well-known in the art;and whichwili vary in shape dependingupon the character of the incision being made. In some. cases it may be a needle, in others a knife, or a wireloop. Between bothof the electrode terminals 47 and'48 and the'inductive reactance 45 is placed aso-called link (blocking) capacitor Strand a main blocking capacitor 51; In the branch individual to the electrode terminal'4z'l', a complementary blocking capacitor 52 is included in the circuit.

The opposite side of the inductive reactance 4:; is connected preferably at the center by'a lead 53 to ground and through amain blocking capacitor 54 to a-dispcrsive electrode SSof the character well known tothe art which makes ground connections to-thc patient and may be a plate conductive blanket or other large area conductor.

In operation the eqaipment is turned on, prior to use, by energizing pre-action' switch 25; It is, however, in safe condition and cannotzcause anincision or accident to the operator until the operator turns on a final-action switch 56 which is in series with the primary of transformer 38. t

The operator now adjusts the energy of discharge by manipulating. a link. capacitor 50. By. this means the energy availablean thecautery. implement may be varied between a very smalland a very large. energy limit depending upon tlie character of surgery being done.

Terminal 48Lwould'be usediwlierehcmostatic action is desired; due.to the fact that there is a heavier discharge.

The preferred dimensions for the various components referred to herein are' as follows, although these dimensions may'be-varied'within the principles of the invention.

Transformer 26 is a step=downtransformer with a primary voltage of'1 '1-0-volts at6'0 cycles and asecondary voltage of 2.5 volts at: 60 cycles.

Transformer 27 is a. similar step-down:- transformer with a. primary voltage of 110 volts-.at 60 cycles. and. a secondary voltage of 6.5 volts at 60 cycles.

Transformen 38uis a step-up transformer; withz a primary voltage of 1:10. volts: at 60 cycles-:anda: secondary voltage of900rvol'ts at: 60 cycles.

Rectifier: tubes 28 and. 30; are preferably of; type 866- Choke coil 32 hasa reactance. of 2.51 millihenries and has a working capacity of 300 milliamperes;

Capacitor 34 is of one microfarad capacity at 2500 volts working capacity.

Resistor 33 has a resistance of 40,000 ohms with a rated capacity of 50 watts.

Choke coil 41 has a reactance of 1 millihenry with a Working capacity of 300 miliarnperes.

Resistor 42 has a resistance of"4-,000 ohms with a working capacity. of. 50 amperes.

Capacitor 43; has-a capacity of 0.002 microfarads at 2,500 volts working capacity.

Capacitor 46 has: a. capacity of 0.001 microfarads at 2,500 volts working capacity.

inductance 'lias a reactance of 24.1 millihenries.

Capacitor 44 has. a. capacityvof 0.0000181 micro-microtarads which withstands a short circuit test at 5000 volts.

Variable capacitor 50 has a range from 9 to 38 micromicrofarads which withstands a short circuit test under 5000volts.

Blocking capacitor 51 base capacityof 0.002 micro larads. at atwork-ing capacity of 2,500.-volts.

Blocking capacitor, 52. has: a capacity of 0.004 micro farads at a working capacity of 2,500.. volts.

Capacitor 54 has a capacity of 0.001 microfarads at'a:

working capacity of 2,500 volts.

it will. be understood, of course, that these dimensions can be changed. to give a device which will have modified character as desired by the user for aparticular char.- acter of service.

in view of my. invention and disclosure variationsandmodifications to meet invidiual whim. or particular. need will doubtless become evident to others skilled in the. art, to obtain all or part of the benefits of my invention. without copying the structure shown and I, therefore, claim all such insofar as they fall within the reasonable spirit and scope of my claim.

Having thus described my invention what I claim as newand desire to secure by'Letters Patent is:

In a device for making an incision in live tissue without shock and without damage to tissue which will prevent normal healing, a full wave rectifier, circuit means connecting the full wave rectifier to a source of alternatingcurrent at normal frequency, a power vacuum tube connected to the output side of the full wave rectifier, a. tank circuit having a capacitative reactanceand an inductive. reactanceconnected tothe output sideof the power. vacua um. tube and connected. to be in resonance, auxiliary blocking condensers between the tank circuit at each-tside: and. the power vacuum tube,.an electrodeterrninah connected to the inductive reactance, and adapted to receive;

anincision electrode, a dispersive electrode connected to a spaced point on the inductive reactance, and blocking: capacitative reactance in series between. the inductive reactance and the electrode terminal and between. the inductive reactance and the dispersive electrode, and a, variable capacitative reactance between the inductive. reactance and the electrode terminal.

References Cited in the file of this patent UNITED STATES PATENTS 874,178 De Forest Dec. 17', 19.07 1,695,485 Fayer Dec. 18,1928 1,724,508 Nauth Aug, 13, 1-929 1,813,902 Bovie July 14, 19.3.1 1,841,968 Lowry Ian. 19,.1932 2,099,511 Caesar Nov. 1.6, 1"}? 2,213,820 Maxon Sept. 3,.1940 2,238,344 Schuler et a1 M Apr. 15,1941

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