US1841968A - Radio-surgical apparatus - Google Patents

Radio-surgical apparatus Download PDF

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US1841968A
US1841968A US73253224A US1841968A US 1841968 A US1841968 A US 1841968A US 73253224 A US73253224 A US 73253224A US 1841968 A US1841968 A US 1841968A
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apparatus
transformer
terminal
connected
electrode
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Nelson H Lowry
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William J Cameron
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    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B18/00Surgical instruments, devices or methods for transferring non-mechanical forms of energy to or from the body
    • A61B18/04Surgical instruments, devices or methods for transferring non-mechanical forms of energy to or from the body by heating
    • A61B18/12Surgical instruments, devices or methods for transferring non-mechanical forms of energy to or from the body by heating by passing a current through the tissue to be heated, e.g. high-frequency current
    • A61B18/1206Generators therefor
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B18/00Surgical instruments, devices or methods for transferring non-mechanical forms of energy to or from the body
    • A61B18/04Surgical instruments, devices or methods for transferring non-mechanical forms of energy to or from the body by heating
    • A61B18/12Surgical instruments, devices or methods for transferring non-mechanical forms of energy to or from the body by heating by passing a current through the tissue to be heated, e.g. high-frequency current
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B18/00Surgical instruments, devices or methods for transferring non-mechanical forms of energy to or from the body
    • A61B2018/00636Sensing and controlling the application of energy
    • A61B2018/0066Sensing and controlling the application of energy without feedback, i.e. open loop control

Description

Jan. 19, 1932.

LOWRY RADIO SURGICAL APPARATUS Filed Aug. 16 1924 4 Sheets-sheet 1 Jan. 19, 1932. N. H. LowRY 1,841,968

RADIO SURGI CAL APPARATUS Filed Aug. 16, 1924 4 sheets-sheet 2 Jan. 19, 1932. y N, H LQWRY 1,841,968

RADIO SURGICAL APPARATUS Filed Aug. 16 1924 4 Sheets-Sheet 3 Jan. 19, 1932. N. H. LowRY 1,841,968 I RADIO SURGICAL APPARATUS Filed Aug. 1e .Y 1924 4 sheets-sheet 4 E@ fr? /NVENTOR Wav mi; Wafffawnm/ Je, A TTORNE YS Patented Jan. 19, 1932 atea .PTENT if;

NELSON H. LOWBYpOF CHICAGO, JILLINOIS, ASSIGNOR T0 WILLIAM J. CAMERON, 0F 'f1 CAGO, ILLINOIS BrADO-SUICAL APPARATUS Application led August 16, 1924. Serial No. 732,532.

rl`his invention relates to improvements in electro-surgical apparatus which operates by cutting the flesh or other tissue and which may be employed for removing abnormal tissues, for dissecting normal tissues, and for various other surgical purposes. The cutting of the flesh or tissue is eected without carbonization of the tissue by a high frequency electrical discharge such as that which is employed in radio sound transmission. The body of the patient forms one terminal or electrode of a secondary circuit and the other terminal or electrode of this circuit serves as the operating instrument which is manipulated by the surgeon duringthe process of performino` the operation or dissection. This secondary circuit in which these terminals or electrodes are connected,

is inductively related by an adjustable highfrequency oscillation transformer with the.

circuit in which the high frequency oscillations are produced and the frequency of thel higher than any frequency which has heretofore been employed in any form of electrosurgical apparatus. Efforts have heretofore been made to use electrical current discharges for dessication surgery and the like but no satisfactor apparatus has heretofore been produced or surgical dissection and opera'- tions such, for example, as the removal of cancers, tumors, and Y other abnormal growths.

The apparatus of the present invention has vnumerous advantages and distinguishing features. The electrode itself is not sharp and does not itself sever the flesh, since the cutting is effected by an electric discharge of high frequency, but the electrode `may be conveniently manipulated by the surgeon to move the ath of the electric discharge and thereby e ect a rapid separation of the tissue. Although the electrode is not hot, the electrical discharge operates to seal the tissue like a hot iron, thereb preventing the spread of malignant cells uring operations for the removal of cancer growths, for example. The electrical effect also serves to kill cancer cells in the immediate 'vicinity ofthe travel of the electrode. Operations performed by means of this apparatus are quickly, even more quickly than wounds4 which are made by ordinary surgical instruments. The cut surface is not burnedk by the apparatus of this invention, but only slightly dehydrated and this brings about a more rapid healing of the tissues than would otherwise be possible. The apparatus makes possible a greater speed of operation with less fatigue to the patient and also with less fatigue to the surgeon because of: the reduced time of the operation and the fact that no pressure is required on the operating instrument. Another important advantage of the invention is that the dehydration prevents bleeding except from large blood vessels which may readily be held by clamps, so that there is little blood loss and the strength of the patient is conserved, while at the same time the operating field is clear due to the fact that the tissues to be operated on are not saturated with blood. The absence of blood in the field of operation reduces the liabilityof infection and no infectioniis ossible from the o` erating instrument itsel because the woun s are automatically sterilized by the high frequency oscillations as they are being cut.

In addition to the use of the apparatus for the removal of cancerous growths, tumors, ulcers, and malignant lesions of all kinds, the apparatus of the present invention may be employed for all ordinary cautery and fulguration work and with improved results due to the fact that there is less scarring and no burning of the tissue.

Various other objects yand advantages of the invention will appear more clearly from the following specification taken with the accompanying drawings in which one embodiment is illustrated. In the' drawings Figure 1 is a diagrammatic view showing the circuit connections of the apparatus and the princisus pal parts thereof;,Fig. 2 shows an enlarged elevation of the operating handle and elec- Fig. 3 is an enlarged section through the movable operating electrode, taken on the line 3-3 of Fig. 2; Fig. 4 shows a top plan view of the cabinet in which the apparatus is mounted with the cover thereof removed; Fig. 5 shows a partial front elevation of the cabinet and apparatus illustrated in Fig. 4; Fig. 6 shows a front elevation of the apparatus with the front of the cabinet and apparatus carried thereby removed; Fig. 7 shows a transverse section taken on the line 7-7 of Fig. 8 Fig. 8 shows a horizontal section taken on the line 8 8 of Fig. 6; Fig. 9 -shows a vertical section through the high frequency oscillation transformer, and Fig. 10 shows a top plan view of the structure illustrated in Fig. 9 with parts thereof broken awa-y.

In Figure 1 of the drawings there is shown a diagrammatic representation of the electrical circuit connections which are preferably employed inthe radio-surgical apparatus of the present invention. These circuit connections are in some respects similar to the connections which are employed in one form of apparatus for radio sound transmission of the continuous wave type but differ therefrom in certain important features. As shown in the drawings, the apparatus comprises a low frequency transformer 20 having a primary winding 2l, a high voltage secondary winding 22 and a low voltage secondary winding 23. The terminals of the primary winding 21 are connected by conductors 24 to a suitable source of supply 25, which may preferably be a 110 volt, 60 cycle7 alternating current system. A switch 2G is connected in the primary circuitfor controlling the operation of the apparatus. The apparatus comprises two vacuum tubes 27, each comprising a plate 28, a filament 29, and a grid 30, these parts being similar in construction to those commonly employed in radio sound transmission. The high voltage transformer winding 22 has its terminals connected by conductors 31 to the plates 28 of the vacuum tubes, and the middle point of the secondary winding 22 is connected by a conductor 32to one terminal of the primary winding 33 of a high frequency transformer 34, of the variable type as indicated by the inclined arrow 34, which has a secondary winding 35. In order to maintain an exact electrical balance between the divisions of the secondary winding 22 of the transformer 20, condensers 36 are connected between the conductors 31 and the conductor 32 which leads from the middle point of the winding 22, thereby effecting the impression of equal voltages upon the two plates 28 of the vacuum tubes. The low voltage winding 23 of the transformer 20 is connected to the filaments 29 of the vacuum tubes which are arranged in parallel electric circuits. A conductor 38 leads vfrom one terminal of the winding 23 and is connected to branch conductors 38a which lead to one terminal of each of the filaments 29. A conductor 39 leads from the other terminal of the winding 23 to a rheostat 40 and a conductor 41 leads from the other terminal'of the rheostat to the other terminals of each of the filaments `29 so that by varying the adjustment of the rheostat 40 the voltage which is impressed on each of the filaments may be regulated as desired. This voltage is indicated by a voltmeter 44. The middle point of the secondary winding 23 of the transformer 2O has a conductor 42 leading therefrom to the terminal of the primary winding 33 of the high frcquency transformer 3'4 opposite that to which the conductor 32 is connected, it being apparent therefore that the terminals of the primary winding 33 are connected to the middle points of each of the secondary windings of the transformer 20.

The grids 30 of the vacuumtubes 27 are connected by conductors 45 to a common conductor 46 which leads through a non-inductive resistance 47, having a condenser 48 connected in parallel therewith, to another conductor 49 which is connected to one terminal of a variometer 50 comprising two inductive windings 51 and 52 which are connected in series and which are capable of relative angular movement in order to vary their inductive effect. The other terminal of the variometer is connected by a conductor 54 to the conductor 32, previously referred to, which leads to one terminal of the transformer winding 33. The variable transformer 34 may be located in inductive relation to the variometer 50 or oscillations may be set up in the transformer due to the usual feed-back relation commonly existing in radio circuits.

The switch 26 in the supply circuit of the.

transformer 20 controls the operation of the apparatus, andfhaving closed this switch and impressed a suitable voltage on the primary winding 21 of the transformer 20, secondary voltages are induced in the windings 22 and 23 and are impressed thereby on the plates 28 and filaments 29 of the vacuum tubes. The voltage on the filaments is indicated by the voltmeter 44, and is regulated by the rheostat 40 until it reaches the value for which the apparatus is designed, preferably about 10 volts. The voltage which is impressed upon the grids 30 of the vacuum tubes and the inductance of the grid circuit are varied by the regulation of the variometer 50 until the whole circuit is brought into oscillation by reason of the oscillatory discharges which take place between the plates 28 and the filaments 29 through the grids 30 which, in the actual construction of the apparatus, are located between them. These undamped high frequency oscillations, are transmitted through the variometer to the primary winding 33 of the oscillation or high frequency transformer 34 with the result that high frequency oscillations are induced in the seconastuces dary winding 35 of this transformer. The wave length of the oscillations generated by the apparatus may preferably be vapproximately eighty metersor less with a corresponding frequency of about three thousand seven hundred and fifty kilocycles per second. @ne terminal of the secondary winding 35 of the oscillation transformer is connected. by a conductor 55,'leading through a series condenser 56.to a plate 57 constitutinglan indifferent electrode adapted to contact with the body of the patient yconstituting the subject to be operated on. A conductor 58 leads from the other terminal of the secondary winding 35 to the movable operating electrode 60 which, upon being brought in proximity to the body of the patient, represented at 61, completes the secondary circuit of the transformer 34, the high frequency discharge between the terminal of the operating electrode 60 and the body of the patient operating to sever the flesh or tissue so that a cut is produced substantially like that made by a sharp knife. A neon tube 62 is connected to the conductor 58, as shown in Fig. l, to act as an indicator, the 'character of the dischargewithin the tube indicating the existence of a sufficiently active high frequency discharge to permit the use of the apparatus for operating purposes. The operating electrode 60, embodied in the apparatus described above, is constructed as shown more particularly in Figs. 2 and 3. v. It comprises a tubular handle 65 of insulating material having mounted therein a metallic member 66 which terminates in a more or less sharp metallic terminal or electrode proper 67 which is only slightly exposed at the end of the insulating handle so that a point discharge is insured. The

metallic member 66 is curved longitudinally and somewhat elliptical in cross-section, to facilitate its use in small openings. The end of the insulating handle 65 adjacent the terminal 67 is tapered as shown at 65a in order to permit the more ready insertion Aof the in strument" into relatively inaccessible places and at the other end of this operating instrument the metallic conductor 6.6 is connected by a sleeve 68 with the extremity of they conductor 58 leading from the oscillation transformer 34. A11 insulating sleeve or ferrule 69 surrounds the conducting sleeve 68 so that the hand of the surgeon is fully protected by insulating material. In using `the operating electrode 60 on the body of the patient, the point or extremity of the terminal 67 is directed toward the surface to be cut so that the electrical discharge takes place from the point, as distinguished from'the surface or curved sid-e of the terminal. When the extremity of the terminal 67 is brought into proximity with the surface of the flesh or tissue of the patient, a cutting of the iesh or tissue begins immediately due to the high frequency .electrical discharge .which takes place j and this cutting is effected without actual `contact of the terminal 67 with the patient.

ditions for operating purposes being indicated by the character of the discharge in the neon tube. rlhe variable transformer may preferably be constructed as shown in` Fig. 9, where it is shown as comprising an outer stationary sleeve having wound thereon the primary winding 33, and a relatively movable sleeve 76 having wound thereon the secondary winding 35. rlhe windings are arranged on the two sleeves so that they are of the same length longitudinally of the sleeves and the inductive elect is varied by regulating the position of the secondary winding within the primary winding. This is accomplished by means of an adjustable threaded member 77, the threads of which are engaged by prongs 78 formed on a bracket 79 which is secured to the movable sleeve 76. lWhen the adjusting member 77 is rotated, the engagement of the prongs 78 with the threads willeect a corresponding movement of the secondary windingin one direction or the other. The rotation of the adjusting member 77 is effected by means of an insulating cap or handle 80 which is secured to the reduced stem 81 of the adjusting member by 'i porting member 84 having mounted therein a bushing 85 Yin which the part 8l rotates. The roper adjustment of the transformer may e determined by trial of the operating electrode or by observing the neon tube which preferably shows a substantially white light when the proper adjustment of the apparatus is attained. l

The various parts of the apparatus which are sho'wn connectedin the circuit of Fig. l are housed within a box or cabinet having the form illustrated particularly in Figs. 6

4and 7. This cabinet is provided with a cover 91 which is hinged at 92 so that it swings upwardly and toward the right as viewed in Fig. 7 in order to reveal certain parts of the apparatus which must be inspected by the surgeon during the operation of the apparatus. The cover is normally held in closed position by means of a spring latch member 93 which is secured on the inside of the cover and which has a hooked extremity 93a adapted to engage alug k94 secured to the boxor cabinet. The latch mem-- ber 93 is releasedfrom the lug 94 by means of a push-button 95. The top of the box or cabinet is closed beneath the cover by means of the insulating supporting plate 84, previously referredto, and by means of a me-A tallic plate or casting 96 which 1s secured t0 the edges of the box andwhich supports the insulating plate.

The transformer 34 is mounted in the cabinet 90 as shown in Fig. 6 with the outer cylinder 7 5 thereof secured to the insulating plate 84 by means of screws or the like connected to the cross arms 97 which are attached to the upper end of the cylinder as shown in Figs. 8 and l0. The lower end of the transformer 34 is spaced somewhat above the'bottom of the cabinet and the bottom wall has mounted thereon insulating lugs 99 carrying spring contact clips 100 which are connected in the electrical circuit and which are adapted to establish electrical connection with the seondary winding 35 of the transformer through spring vanes 101 which are attached to the cylinder and which have upwardly directed arms within the cylinder terminating in bifurcated parts 102 which are adapted to slide on contact plates 103 which are suitably insulated and connected to the secondary winding so that an electrical connection is made with the secondary winding in all positions of the sleeve 76.

The variometer 50 is located in the cabinet in a position oppositevthat of the transformer 34 and is similarly suspended from the insulating plate 84. The variometer is provided with an operating handle 105 which is located above-the plate 84 so that it is exposed for operation when the cover is lifted upwardly. The casing of the variometer is provided adjacent the lower part thereof with contact terminals 107 which are adapted to be engaged by flexible springs 108 extending upwardly from' an insulating plate 109'located on the insulating lugs 110 secured to the bottom wall of the box or cabinet. In this way an electrical connection is readily made with the terminals of the variometer, it being understood that the springs 108 are connected in the circuit by the conductors heretofore described which are located within the cabinet but are not Vin the grid circuit, is located in an insulating tube 111 mounted on the bottom wall of the casing by means of contact springs 112 which are connected to insulating blocks 113 carried by the bottom wall.

The two vacuum tubes 27'are located in the rear corners of the box and their upper ends project through openings 115 in the plate 96 so that they are exposed when the cover 91 is elevatedfThese vacuum tubes are suitably supported on the bottom wall of the casmg as shown particularly in Fig. 7. u

Between the openings for the vacuum tubes 27, `the plate 96 is provided with an upward projection 116 having a flat face 117 which carries the dial 118 of the voltmeter heretofore referred to. In front of the voltmeter,

the plate 117 is rovided with an opening 119 through whic the neon tube 62 may be observed by the operator, this tube being mounted on a bracket 120 immediately beneath the plate 84, as shown in Fig. 7 The plate 84 also has mounted therein terminal sockets 121 and 122, as shown in Fig. 4, these sockets being located adjacent the front edge of the insulating ,plate 84 and being adapted to receive the terminals of the conductors which lead to the electrode 57 and the movable operating electrode 60, respectively.

Other parts which need to be manipulated by the operator of the apparatus are located conveniently in the front wall of the cabinet, as shown in Fig. 5, these being the devices for regulating the resistance in the filament circuit and the switch for controlling the primary circuit of the transformer 20. As shown in Fig. 8, the end wall of the cabinet is provided with a socket 125 through which a connection can be made with the ordinary 110 volt, 60 cycle, alternating current lighting circuit by which the primary of the transformer 20 is supplied. The connections from the socket 125 are controlled by means of the switch 26 which is operated by a shaft extending through the front wall of the cabinet and controlled by an operating handle 126. This handle has an arrow 127 .thereon which points toward the various positions of the switch which are indicated by the words On and Off mounted on a dial plate 128 located around the handle 126. At the other side of the front wall, there is provided a handle 130 for operating the rheostat 40 by which the voltage on the filaments of the vacuum tubes is regulated. The handle 130 is similarly provided with an arrow 131 pointing toward a dial plate 132 which is mounted around the handle and which markedthereon an arrow 133 to indicate the direction in which the handle should be turned to increase the volt age, this voltage being determined by observation of the voltmeter, as heretofore indicated.` The rheostat 40 is mounted immediately behind the front wall of the cabinet, as shown in F ig. 7, sot-hat the operating handle 130 can be directly connected thereto.

The transformer 20, which is relatively heavy as compared with the other parts of the apparatus, is Vmounted between the vacuum tubes 27 and between the positions occupied by the transformer 34 and the variometer 50, as shown in Fig. 7. The frame of the transformer 20 is secured to the rear wall of the easing by means of screws or other fastening devices 135 which also serve as fastening means forsecuring in place a handle 136 by which the entire apparatus can be carried from one place to another. In'this way the heavy part of the apparatus has a direct connection with the supporting handle. The condensers 36 are mounted above the casing of the transformer and the other condensers 48 65 circuit.

and 56 are loca'ted in proximity to the front Wall of the casing, as 'shown in Fig. 8, so that all of the principal parts of the apparatus are contained within the cabinet. All of the 5 Wiring connections, except those leading for the sake of clearness these conductors have 10 not been shown in the drawings of Figs. 4 to l0 inclusive. In order that the heat generated by the apparatus may be dissipated and the apparatus maintained in a sufficiently cool condition during its operation, the cabi- 15 net 90 is provided with a plurality of ventilating openings which are covered by perforated vcaps 140 having. openings therethrough of suliicient size to permit a thorough ventilation of the interior of the cabinet. The parts of the apparatus of the present invention may be constructed according to various designs and the resistances, inductances, and capacities may have various values and relative values. In one form of apparatus which has heretofore been successfully operated for surgical purposesv of the type hereinbefore referred to, a 110 volt, 60

, cycle alternating current was impressed on the primary of the transformer 20 and the secondaryv windings of the transformer were designed to give 2000 volts across the secondary winding 22, this voltage being equally divided between the two halves of the windin on opposite sides of the conductor 32, while the secondary winding 23 was designed to give a pressure of 10 volts, subject to regulation by the rheostat 40. The condensers 36 had a capacity of .002 microfarads each and the condensers 48 had a capacity of .0003 microfarads, while the resistance 47 in the grid circuit had a resistance of 5000 ohms. In the apparatus referred to, the high frequency oscillation transformer 34 was designed so that the primary winding 33 bore the relation to the secondary winding 35 of 99 to 49 and the condenser 56 employed in the work circuit had a capacity of .002 microfarad. With these proportions, the apparatus operates to cut the flesh or tissue readily without burning.

It will beapparentthat the apparatus not only has the advantages hereinbefore referred to, as well as many others. but that it is compact andmav be used and moved about conveniently. In assembling the apparatus in the cabinet the various devices carried by the c plates 84 and 96 are first assembled thereon and then upon a plying the plates tothe cabinet, the transformer 34 and the variometer 60 50 automatically becori electrically connected to the spring conta vanes carried`4 by the casing. In the use ofthe device, it may be moved .from place to place and, in general, it may be operated from the usual lighting Although one form of apparatus has been shown and described by way of illustration, it will be understood that it may be embodied in .various other forms without departing from the scope of the appended claims.

I claim:

1. In electro-surgical cutting apparatus, an electrical circuit, a vacuum tube device connected in said circuit, said device comprising a plate and a filament and a grid, a source of electric current, means connected to said source for impressing voltages on said plate, said filament, and said grid, said means comprising a plurality of branch circuits, means for varying the voltage impressed on said lament, a variable inductance in the circuit of said grid, a transformer in which high frequency oscillations are produced by the l,operationof said vacuum tube device, means for connecting one terminal of said transformer to a surgical patient, means for connecting another terminal of said transformer to a movable operating electrode, and means for regulating the inductive effect of said transformer.

2. In electro-surgical apparatus, asource of oscillating current, means for connecting one terminal of said source to the surgical subject, a movable electrode connected tothe rounding said electrode and leaving only the extreme tip portion thereof exposedn 3. In electro-surgical apparatus, asource of oscillating current, means for connecting one terminal of said source-to the surgical subject, a movable electrode connected to the other terminal of said source, and aninsulating member surrounding said electrode, and leaving the extreme end portion thereof exvlos posed, said insulating member and said electrode adjacent said exposed portion of-said electrode being curved longitudinally, said exposed portion terminating in a point.

.4. In electro-surgical apparatus, the source of oscillating current, means for connecting one terminal of said source to the surgical subject, a movable electrode connected to the other terminal of said source, and an insulating member surrounding said electrode and leaving the end portion thereof exposed, said exposed extremity of said electrode being elliptical in. cross section.

NELSON H. LowaY.

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