US3886945A - Cryosurgical apparatus - Google Patents

Abstract

There is disclosed a cryosurgical apparatus of the type which operates from a source of compressed gas. It includes a handle portion with removable and interchangeable probes. A defrost valve in the exhaust conduit permits easy and quiet operation by the surgeon. It is constructed in such a manner that the exhaust valve cannot be closed unless the probe is fully seated in the handle. It also includes an improved nozzle which is substantially less critical than prior art nozzles and permits simplified and less expensive construction. The foregoing abstract is not to be taken either as a complete exposition or as a limitation of the present invention. In order to understand the full nature and extent of the technical disclosure of this application, reference must be had to the following detailed description and the accompanying drawings as well as to the claims.

Description

United States Patent 11 1 Stumpt et al.

1111 3,886,945 June 3, 1975 CRYOSURGICAL APPARATUS {75] Inventors: Joseph G. Stumpi, Fairfield; Joseph F. Andera, Trumbull, both of Conn.

[73] Assignee: Frigitronics of Conn., lnc., Shelton,

Conn.

[63] Continuation-impart of Ser. No. 262,543. June 14,

1972, Pat. No. 3.807.403v

Primary Examiner-Channing L. Pace Attorney, Agent, or Firm-Buckles and Bramblett ABSTRACT There is disclosed a cryosurgical apparatus of the type which operates from a source of compressed gas. it includes a handle portion with removable and interchangeable probes. A defrost valve in the exhaust conduit permits easy and quiet operation by the surgeon.

52 us. (:1 128/303.1; 239/597 It is constructed such a manner that the exhaust 511 int. c1. A6lb 17/36; BOSb 1/00 valve be clsed unless Probe is My Seated 58 Field ofSearch 62/293- i2s/303.1- the handle includes an improved "0111c which is substantially less critical than prior art 1102 zles and permits simplified and less expensive con- [56] References Cited Strucuon- I ED ST E PATENTS The foregoing abstract is not to be taken either as a 359 602 3H8 Gray 239,597 X complete exposition or as a limitation of the present 1,0511069 1/1913 Bahni I:It:12:11:13.... 239 597 understand mute and 5 5 (M926 Spigdmire 239/597 X extent of the technical disclosure of this application, 2,645,097 7/1953 Posch l28/303. UX reference must be had to the following detailed 3,4ll,483 ll/1968 Canoy l28/303.l X description and the accompanying drawings as well as 3,696 8l3 l0/l972 Wallach 128/3031 to the claims, 3,807,403 4/l974 Stumpf et al. [28/3031 766,100 4/1934 France 239/597 7 71526628 44, 5 60 M V f/ i i t a 131: is

CRYOSURGICAL APPARATUS BACKGROUND OF THE INVENTION This application is a continuation in part of our copending US. Pat. Ser. No. 262,543, filed June 14,1972 now US. Pat. No. 3,807,403, for Cryosurgical Apparatus".

This invention pertains to cryosurgical instruments of the type which are cooled under the influence of high pressure gas escaping from an orifice. Instruments of this type are well known in the art and are widely employed for a number of surgical procedures such as the necrosis of diseased tissue. Several gases exhibit the Joule-Thomson effect and may be used in the operation of the instrument. The most common, however, are nitrous oxide and carbon dioxide.

In instruments of this type, the gas expansion orifice is of an extremely small size and in all prior art instruments the spacing between the orifice and the inner wall of the cooling tip is extremely critical. For example, with prior art instruments, the orifice is positioned approximately 0.050 inch from the inner wall of the tip and the permitted tolerance is only 0.010 inch. This results in such instruments being difficult and costly to manufacture For example. the parts of such instruments are commonly threaded so that they may be factory adjusted prior to shipment.

Another problem connected with prior art instruments of this type is found in the exhaust valve of instruments which have controlled defrost. For example, one such instrument is normally warm, which means that the exhaust valve is normally closed and the device is filled with compressed gas at bottle pressure. As the bottle gas pressure may commonly be as high as 800 psi, it will be quite apparent that this creates an explosion hazard. The exhaust valve used in this prior art de vice comprises a cylindrical piston which seats against a small exhaust orifice and is retained in the seated position by means of a heavy spring. The piston is raised against the force of a spring by means of a finger operated toggle. When the surgeon wishes to cool the probe tip, he must apply substantial force to depress the toggle which is, itself, detrimental, particularly in the case of very delicate surgical procedures. Secondly, as soon as the piston begins to leave the orifice, the full bottle pressure, which was formerly applied only to a small area of the piston, is now applied to the full area of the piston end, slamming the piston open with an explosive-like report.

Still another problem with prior art devices arises from the fact that most of them are designed with probe tips of specific shapes and sizes. This requires a surgeon to have different instruments for different surgical applications. It has been proposed to provide a single in strument with interchangeable probes. However this creates a problem due to the high pressures referred to in the preceding paragraph. If a probe were not fully seated, by negligence or otherwise, or if it were not fully seated because of a defect such as stripped threads, the high pressures involved could result in the probe and tip being forcibly ejected during a surgical procedure with potentially disastrous results.

Accordingly, it is a primary object of the present invention to provide an improved cryosurgical instrument of the gas operated type having replaceable and interchangeable probe tips. Another object is to provide such an instrument wherein the exhaust valve cannot be closed to pressurize the instrument unless the probe is fully seated. Another object is to provide such an instrument which is only intermittently exposed to full bottle gas pressure. Another object is to provide such an instrument which has a substantially silent and easily operated exhaust valve. The manner in which these objects are achieved will be apparent from the following description and appended claims.

SUMMARY OF THE INVENTION The invention comprises a gas operated cryosurgical instrument which comprises a handle and a movable first valve member in the handle. A tubular exhaust conduit terminates at one end in a hollow tip of high thermal conductivity. The other end defines a second valve member and includes means for detachably securing the exhaust conduit to the handle. A gas delivery conduit extends through the exhaust conduit when it is so secured and terminates at a nozzle within the tip. Means are provided for selectively advancing the first valve member against the second valve member to close the exhaust conduit. Means are also provided for limiting the movement of the first valve member to prevent closure of the exhaust conduit when it is improperly secured to the handle.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. I is a perspective view of a cryosurgical instru ment in accordance with the present invention connected to a source of bottled gas;

FIG. 2 is an enlarged cross section taken through the instrument of FIG. 1;

FIG. 3 is a cross section of the exhaust valve of FIG. 2 shown in its closed position;

FIG. 4 is a greatly enlarged cross section of the nozzle portion of the apparatus;

FIG. 5 is an illustration of the gas jet obtained with the nozzle of FIG. 4;

FIG. 6 is a cross section taken substantially along theline 66 of FIG. 5;

FIG. 7 is an illustration of one type nozzle used in the prior art;

FIG. 8 is a cross section taken substantially along the line 88 of FIG. 7;

FIG. 9 is an illustration of another type nozzle used in the prior art;

FIG. 10 is an enlarged cross section showing the orifice of the FIG. 9 nozzle; and

FIG. 11 shows still another type nozzle used in the prior art.

DESCRIPTION OF THE PREFERRED EMBODIMENT With particular reference to FIG. 1, there is disclosed an instrument of the type utilized in treating cervicitis. It comprises anelongated probe 10 mounted in a handle l2 and terminating in a substantially conicalhollow applicator tip 14. A line I6 is connected between the instrument and asuitable source 18 of pressurized gas. Atrigger 20 extends from the handle for selective defrosting as will be explained.

Referring to FIG. 2, the handle I2 will be seen to define arecess 22 for thetrigger 20 and aTshaped recess 24 communicating therewith and enclosing a metal T fitting 26. The horizontal portion of fitting 26 hasinternal threads 28 and the lower end of the vertical portion is provided with similarinternal threads 30. Within the vertical portion of the T fitting 26 and near its juncture with the horizontal portion. there is defined aninternal shoulder 32. Mounted against theshoulder 32 is aresilient O ring 34. Bearing against the O-ring 34 is a circularplastic sealing ring 36. Atrunnion ball 38 is mounted against the sealingring 36. Thetrunnion ball 38 is integral with anupper rod 40 andlower rod 42. The end ofupper rod 40 includes a flattenedportion 44 which defines anopening 46 therein.Opening 46 is substantially coaxial with the bore of the horizontal portion of T-fitting 26, as illustrated in FIG. 2. Thelower rod 42 extends into therecess 22 ofhandle 12 and thetrigger 20 is secured tolower rod 42 by means of aset screw 48. The trunnion ball assembly is retained within the T-fitting by a lowerplastic sealing ring 50 supporting thetrunnion ball 38, acompression spring 52, and anannular retainer nut 54 threaded into thethreads 30. A triggerreturn coil spring 56, supported within abore 58 intrigger 20 and seated against the back wall ofrecess 22, maintains the trigger in its normally extended position as shown in FIG. 2.

The flexiblegas delivery line 16 is connected by means of aretainer ring 60 to the end of a stainlesssteel delivery tube 62 which extends forwardly outward of the handle and terminates at anozzle 64. The outer diameter oftube 62 is less than the diameter of theopening 46 in the flattenedportion 44 ofupper rod 40. In one embodiment, thedelivery tube 62 is a gauge stainless steel hypodermic tube. Thetube 62 passes through aball 66 to which it is integrally secured as by welding.

Theprobe tip 10 is a complete assembly which is detachable from the handle portion of the instrument. It comprises a threadedsleeve 68 which screws into the T-fitting 26 as shown. Fixedly secured to thesleeve 68, as by welding, is astop ring 70. An O-ring 72 provides a seal betweenstop ring 70 and the T-fitting 26. Fixedly secured to the inside ofsleeve 68 is anexhaust conduit 74 which surrounds, and is spaced from,delivery tube 62. The distal end ofexhaust conduit 74 carries a sleeve 76 to which is secured thehollow tip 14. Surrounding and spaced from theexhaust conduit 74 is an insulator tube 78, secured at one end to the sleeve 76 andtip 14 and at the other tosleeve 68 and stopring 70. This tube is provided with aknurled finger grip 80. The end ofexhaust conduit 74 forms, withsleeve 68, a taperedvalve seat 82.

The construction ofnozzle 64 will be best understood by reference to FIG. 4. As will be seen therein, the internal diameter of thedelivery tube 62 is reduced via a smoothwall reduction passage 84 to a cylindricalgas discharge passage 86. This configuration is achieved by inserting into the end of the hypodermic tube a hardened wire having an external diameter equal to the desired diameter of the gas discharge passage. The end of the tube is then swaged onto the wire and the wire is removed. In one actual embodiment, thetube 62 has an internal diameter of 0.059 inch and the internal diame ter of thegas discharge passage 86 is 0.01065 inch. The distance from the nozzle tip to the beginning of reduction (A FIG. 4) is 0.20 inch and the distance between the nozzle tip and the end reduction (8) is 0.12 inch.

The performance of thenozzle 64 is strikingly superior to those of the prior art. The reason for this is not fully understood but is believed to be due to the smooth continuous inner surface formed by thereduction passage 84 and thegas discharge passage 86. This is believed to prevent gas turbulence and permit laminar flow out ofnozzle 64. FIG. 5 illustrates the gas flow fromnozzle 64 as actually observed in practice. As will be seen, it presents an elongated flamelike appearance and shape. FIGS. 7-]] illustrate three prior art nozzle constructions and the jets obtained thereby. FIGS. 7 and 8 illustrate a pinched tube configuration. FIGS. 9 and 10 illustrate a rolled end construction. and FIG. 11 illustrates a type of orifice known as a double reduction orifice which comprises a series of tubes of reduced diameter. The jets from these prior art nozzles appear as indicated. In these prior art nozzles, the dis tance from the orifice to the wall of the applicator tip is very critical and the spacing must be quite close. As an example, this distance may be 0.050 inch with a tol erance of 0.010 inch. In contrast, in utilizing the nozzle of this invention, the distance from the nozzle tip to the wall may be 0.250 inch with a tolerance of i 0.060 inch. Accordingly, by means of this invention, manufacture and assembly are greatly simplified, resulting in a highly effective instrument at a much lower cost.

The described nozzle construction may be utilized in connection with either a non-defrostable or a defrostable cryosurgical probe. The probe illustrated herein is of the defrostable type. Defrosting is obtained by means of the valve illustrated in detail in FIGS. 2 and 3. When the valve is in its normally open position as shown in FIG. 2, high pressure gas entering throughdelivery line 16 passes through thedelivery tube 62 tonozzle 64. From the nozzle it expands intotip 14 causing the tip to be cooled by the .IouleThomson effect. The expanded gas then passes rearwardly throughexhaust tube 74 and out of the instrument through the T- fitting 26 and therecess 24. If desired, it may be remotely exhausted through an exhaust line enclosingdelivery line 16. The high pressure exhaust gas tends to maintain the exhaust valve formed by theball 66 and thevalve seat 82 in its normally open position, with the ball retracted from the seat as shown in FIG. 2. In order to defrost the instrument, thetrigger 20 is depressed by the surgeon, whereupon thetrunnion ball 38 and therods 40, 42 assume the positions illustrated in FIG. 3, forcing theball 66 forwardly against thevalve seat 82, forming a gas tight seal. With the exhaust valve closed, gas pressure withintip 14 rises to bottle pressure and the heat of compression causes rapid defrosting of the probe tip. It is important to note, however, that either of two different limit stops restrict the forward movement ofball 66. These include the point C which may be contacted by theupper rod 40 and the point D which may be contacted by thelower rod 42. No matter how much force is exerted ontrigger 20, theball 66 can be driven no further forward than the limit set by a stop. This is a very significant improvement because it means that. if theprobe tip 10 is not fully seated within the T-fitting 26, the exhaust valve cannot be closed and pressurization cannot occur.

With an instrument of the type disclosed herein. a single handle and valve unit may be supplied with a plu rality of probes and tips for performing various surgical procedures. These may be readily interchanged by the surgeon or his assistant without the danger of a probe being improperly inserted. Furthermore as the valve is normally open, it will be closed only for the period of time during which the surgeon desires to defrost the probe tip. Therefore. the instrument is exposed to full bottle pressure only intermittently and for short periods of time. greatly increasing the safety of the apparatus.

It is believed that the construction and operation of this invention will now be apparent to those skilled in the art. It will also be apparent that a number of variations and modifications may be made in this invention without departing from its spirit and scope. Accordingly. the foregoing description is to be construed as illustrative only, rather than limiting. This invention is limited only by the scope of the following claims.

We claim:

1. A gas operated cryosurgical instrument which comprises: a handle defining a socket therein; a movable first valve member in said handle; a tubular exhaust conduit terminating at one end in a hollow tip of high thermal conductivity, the other end defining a second valve member and including means detachably securing said exhaust conduit seated within said socket; a gas delivery conduit mounted in said handle and extending through said socket and through said exhaust conduit when so secured and terminating at a nozzle within said tip; means for selectively advancing said first valve member against said second valve member to close said exhaust conduit when said exhaust conduit is fully seated within said socket; and means for limiting the movement of said first valve member to prevent closure of said exhaust conduit when the conduit is not fully seated within said socket.

2. The instrument of claim 1 wherein said first valve member is carried by said gas delivery conduit.

3. The instrument ofclaim 2 wherein said advancing means comprises a manually operable trigger connected to advance both of said delivery conduit and valve member.

4. The instrument of claim I wherein said first valve member comprises a ball.

5. The instrument of claim 1 wherein said nozzle includes a cylindrical gas discharge passage of smaller diameter than said delivery conduit and a smoothly curved reduction passage therebetween.

6. The instrument of claim 1 wherein said advancing means comprises: pivot means within said handle; a rod supported by said pivot means having a first end engaging said first valve member on one side of said pivot means and a second end on the other side of said means; and a manually operable trigger secured to the second end of said rod.

7. The instrument ofclaim 6 wherein said pivot means comprises a trunnion ball rotatably supported within said handle. 4

8. The instrument of claim 7 wherein said first valve member is carried by said gas delivery conduit.

9. The instrument of claim 8 wherein said first valve member comprises a ball.

10. The instrument of claim 9 wherein said nozzle includes a cylindrical gas discharge passage of smaller diameter than said delivery conduit and a smoothly curved reduction passage therebetween.

Claims (10)

1. A gas operated cryosurgical instrument which comprises: a handle defining a socket therein; a movable first valve member in said handle; a tubular exhaust conduit terminating at one end in a hollow tip of high thermal conductivity, the other end defining a second valve member and including means detachably securing said exhaust conduit seated within said socket; a gas delivery conduit mounted in said handle and extending through said socket and through said exhaust conduit when so secured and terminating at a nozzle within said tip; means for selectively advancing said first valve member against said second valve member to close said exhaust conduit when said exhaust conduit is fully seated within said socket; and means for limiting the movement of said first valve member to prevent closure of said exhaust conduit when the conduit is not fully seated within said socket.

1. A gas operated cryosurgical instrument which comprises: a handle defining a socket therein; a movable first valve member in said handle; a tubular exhaust conduit terminating at one end in a hollow tip of high thermal conductivity, the other end defining a second valve member and including means detachably securing said exhaust conduit seated within said socket; a gas delivery conduit mounted in said handle and extending through said socket and through said exhaust conduit when so secured and terminating at a nozzle within said tip; means for selectively advancing said first valve member against said second valve member to close said exhaust conduit when said exhaust conduit is fully seated within said socket; and means for limiting the movement of said first valve member to prevent closure of said exhaust conduit when the conduit is not fully seated within said socket.

2. The instrument of claim 1 wherein said first valve member is carried by said gas delivery conduit.

3. The instrument of claim 2 wherein said advancing means comprises a manually operable trigger connected to advance both of said delivery conduit and valve member.

4. The instrument of claim 1 wherein said first valve member comprises a ball.

5. The instrument of claim 1 wherein said nozzle includes a cylindrical gas discharge passage of smaller diameter than said delivery conduit and a smoothly curved reduction passage therebetween.

6. The instrument of claim 1 wherein said advancing means comprises: pivot means within said handle; a rod supported by said pivot means having a first end engaging said first valve member on one side of said pivot means and a second end on the other side of said means; and a manually operable trigger secured to the second end of said rod.

7. The instrument of claim 6 wherein said pivot means comprises a trunnion ball rotatably supported within said handle.

8. The instrument of claim 7 wherein said first valve member is carried by said gas delivery conduit.

9. The instrument of claim 8 wherein said first valve member comprises a ball.

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