Patent Publication Number: US-7582244-B2

Title: Electrosurgical electrode shroud

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
   This application is a continuation of U.S. patent application Ser. No. 11/165,891 filed on Jun. 24, 2005, now U.S. Pat. No. 7,060,064, which is a continuation of U.S. patent application Ser. No. 10/358,450 filed on Feb. 4, 2003, now U.S. Pat. No. 6,986,768, which is a continuation of PCT/US01/44544 filed Nov. 28, 2001, which claims benefit of U.S. Provisional Application Ser. No. 60/255,744 filed Dec. 15, 2000. 

   BACKGROUND 
   1. Field of the Invention 
   The present disclosure relates to an electrode shroud and, more particularly, to an electrosurgical electrode shroud which facilitates correct insertion of the electrode into an electrosurgical instrument. 
   2. Description of the Related Art 
   As surgical knowledge and techniques have progressed, there has been a corresponding trend toward size reduction of surgical incisions and invasive instruments, thus decreasing patient trauma and contributing to rapidity of patient recovery. This has led to the practice of laparoscopic and other surgical procedures using small medical electrodes. When using medical electrodes during the performance of a surgical procedure, different types of currents can be employed for different procedures. For example, fully rectified, fully filtered currents can be used for cutting tissue; for cutting with coagulation; and for hemostasis. Spark gap currents can be used for fulguration and dessication techniques. Various electrode configurations are also available; for example, metal needles for making incisions, wire loops, round or diamond shape, for planing and contouring tissue, balls for coagulation and hemostasis, and scalpel shapes for incision and excision of tissue. In all these known electrode configurations, the working end of the electrode is electrically conductive, usually metallic, and is fully exposed, so that all sides of the electrode working end are capable of transmitting the high frequency currents to the tissue. 
   Thus, electrosurgical electrodes are known in the art and are used for a variety of surgical procedures. For example, U.S. Pat. No. 6,004,318 to Garito et al. discloses an electrosurgical coagulation electrode to accomplish direct cyclocoagulation for treating glaucoma. U.S. Pat. No. 4,517,975 to Garito et al. discloses an electrosurgical electrode tip adapted for a nail matrisectomy procedure. 
   Each of the electrosurgical electrodes discussed above and known in the prior art include a first end and a second end. The first or distal end is an active exposed tip which is used for applying the electrical signal to the patient. The active exposed tip of the first end is supported by structure that is completely electrically insulated to avoid damage to surrounding tissue, and to allow the physician to use these inactive insulated parts to help position and guide the active tip, which is the only part capable of treating tissue, during the surgical procedure. 
   The second or proximal end is configured for connection to an electrosurgical apparatus. More specifically, the second end is configured to be inserted into the end of an electrosurgical apparatus which provides the electrical input to the electrode. Moreover, the prior art includes provisions for assisting electrode connection to the electrosurgical apparatus. For example, the Model E2100 and Model E2550 reusable electrosurgical pencils, available from Valleylab, Boulder, Colo., include a flange on the distal end of the pencil which assists in securing the electrode to the pencil. Furthermore, the prior art includes insulated electrodes having a hard elongated opaque or solid colored boot-type shroud mounted on the end of the electrode which is configured for insertion into an electrosurgical apparatus. A function of the prior art shroud is to minimize electrical arcing between the electrode and surrounding objects at the point of connection to the electrosurgical apparatus. Examples of the prior art electrodes with opaque shrouds include model numbers E1510 through E1513 single use stainless steel electrodes which are available from Valleylab, Boulder, Colo. The prior art opaque shrouds may also include a circumferential seal formed on an inner surface of the shroud for forming a seal around the electrosurgical apparatus as it is inserted into the shroud. In another prior art technique, a section of an opaque rubber catheter having a flared end is separately fitted over the junction of the electrode and the pencil. 
   One advantage of the present invention over the prior art electrode shrouds is that the present invention provides the surgeon with the ability to visually confirm that the electrode is fully seated within the electrosurgical apparatus. 
   SUMMARY 
   An electrosurgical electrode shroud is provided including a hollow substantially cylindrical member having a first end portion and a second end portion; the first end portion defining an opening which is configured and dimensioned to receive an electrosurgical electrode assembly therein; and the second end portion defining an opening which is configured and dimensioned to receive an electrode mounting portion of an electrosurgical instrument, wherein at least the second end portion is formed of a substantially translucent material. The electrosurgical electrode shroud may further include a visual or tactile indicator on the second end portion for indicating a depth of penetration of the electrosurgical instrument within the second end portion when viewed by the surgeon through the translucent material. 
   The electrosurgical electrode shroud may further include a frustoconical transition portion between the first end portion and the second end portion. The inside diameter of the opening defined by the first end portion is preferably configured to fit an outside diameter of the electrosurgical electrode assembly received therein. The inside diameter of the opening defined by the second end portion is substantially equal to an outside diameter of the electrosurgical instrument received therein. The shroud is preferably formed of an elastomeric material to enable the shroud to be stretched to fit over the electrosurgical electrode and the electrosurgical instrument thereby ensuring a tight fit. 
   An electrosurgical electrode assembly is also provided having an elongate electrically-conductive shaft member with a proximal end for receiving electrosurgical currents from an electrosurgical instrument and a distal end, wherein the improvement includes an electrosurgical electrode shroud comprising a hollow substantially cylindrical member having a first end portion and a second end portion; the first end portion defining an opening which is configured and dimensioned to receive the electrosurgical electrode assembly therein; and the second end portion defining an opening which is configured and dimensioned to receive an electrode mounting portion of the electrosurgical instrument, wherein the at least second end portion is formed of a substantially translucent material. The electrosurgical electrode assembly may also include at least one layer of insulating material formed on the electrically-conductive shaft. 
   These features and advantages of the present disclosure will become apparent from the following detailed description of illustrative embodiments, which is to be read in connection with the accompanying drawings. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     For a better understanding of the invention, reference is made to the following description of exemplary embodiments thereof, and to the accompanying drawings, wherein: 
       FIG. 1  is a side view illustrating an electrosurgical electrode diagrammatically connected to an electrosurgical apparatus; 
       FIG. 2  is a side view illustrating an electrosurgical electrode having a needle-shaped active tip; 
       FIG. 3  is a side view illustrating an electrosurgical electrode with tip protectors; 
       FIG. 4  is a top view illustrating an electrosurgical electrode having an electrode shroud installed thereon in accordance with the present invention; 
       FIG. 5  is a side cross-sectional view illustrating an electrosurgical electrode having an electrode shroud installed thereon in accordance with the present invention; and 
       FIG. 6  is a side cross-sectional view illustrating a mold for forming a safety sleeve on an electrosurgical electrode. 
   

   DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
   The present disclosure describes an electrosurgical electrode shroud including a hollow substantially cylindrical member having a first end portion and a second end portion. The first end portion defines an opening which is configured and dimensioned to receive an electrosurgical electrode assembly therein. The second end portion defines an opening which is configured and dimensioned to receive an electrode mounting portion of an electrosurgical instrument, and at least the second end portion is formed of a substantially translucent material. As used herein, translucent is intended to encompass clear or tinted material as well as material capable of transmitting light while having sufficient diffusion to prevent perception of distinct images. 
   Referring now in specific detail to the drawings in which like reference numerals identify similar or identical elements throughout the several views, and initially to  FIG. 1 , one embodiment of an electrosurgical electrode utilized in conjunction with the electrode shroud of the present disclosure is shown generally as electrosurgical electrode  10 . 
   Electrosurgical electrode  10  includes an elongate electrically-conductive shaft member  12  with a distal end  14  and a proximal end  16 . Distal end  14  is configured to receive electrosurgical currents from an electrosurgical apparatus  18 . Although distal end  14  may be formed in any shape known to one having ordinary skill in the art, distal end  14  illustrated in  FIG. 1  is flattened to form a thin, flat, slightly-flexible strip. The tip of distal end  14  is rounded. 
   The center region of electrosurgical electrode  10  is coated with first and second layers of electrically-insulating coatings  20  and  22 , for example of rubber or plastic, which may be of any desired thickness. Preferably, first layer of electrically-insulating coating  20  is a PTFE coating and second layer of electrically-insulating coating  22  is a polyolefin coating. Second layer of electrically-insulating coating  22  is configured to at least partially overlap first layer of electrically-insulating coating  20 . Further, second layer of electrically-insulating coating  22  preferably includes a substantially conical shaped portion to prevent over insertion of the shaft member into a source of electrosurgical currents. 
   Referring now to  FIG. 2 , another embodiment of an electrosurgical electrode utilized in conjunction with the electrode shroud of the present disclosure is shown generally as electrosurgical electrode  30 . Electrosurgical electrode  30  also includes an elongate electrically-conductive shaft member  32  with a distal end  34  and a proximal end  36 . Although distal end  34  may be formed in any shape known to one having ordinary skill in the art, distal end  34  illustrated in  FIG. 2  terminates in a pointed tip similar to a needle. Distal end  34  is preferably coated with a silicon coating such as disclosed in U.S. Pat. No. 5,702,387 to Arts et al. and assigned to Valleylab Inc., Boulder, Colo. Electrosurgical electrode  30  is coated with first and second layers of electrically-insulating coatings  40  and  42 , for example of rubber of plastic, which may be of any desired thickness. 
     FIG. 3  illustrates electrosurgical electrode  30  having a tip protector  44  positioned over distal end  34  and a shank protector  46  positioned over proximal end  36 . Tip and shank protectors  44  and  46  protect the proximal and distal ends of electrosurgical electrode  30  during shipping and storage. 
   Referring now to  FIGS. 4 and 5 , an embodiment of an electrosurgical electrode shroud  50  in accordance with the present disclosure is illustrated. Electrosurgical electrode shroud  50  is illustrated mounted on an electrosurgical electrode  30 . 
   Shroud  50  Is formed as a hollow substantially cylindrical member having a first end portion  52  and a second end portion  54 . First end portion  52  defines an opening which is configured and dimensioned to receive electrosurgical electrode assembly  30  therein. Reduced diameter section  63  and enlarged section  65  of first portion  52 . facilitate gripping by the fingers of an operator during insertion and withdrawal of the electrode  30  from a pencil. Preferably gripping is enhanced by a roughened or textured surface  67  of section  63 . 
   Second end portion  54  defines an opening which is configured and dimensioned to receive an electrode mounting portion of an electrosurgical apparatus (not shown). First end portion  52  and second end portion  54  are preferably joined by a frustoconically shaped transition portion  53 . The wall thickness of second end portion  54  is preferably in the range of about 0.030 inches to about 0.050 inches. The opening in second end portion  54  is preferably molded to an angle in the range of about 5 to about 10 degrees to facilitate smoother insertion of an electrosurgical apparatus into the opening formed by second end portion  54 . On a four inch electrode, a preferred length of shroud  50  is approximately 0.80 inches with first end portion  52  being approximately 0.40 inches long, transition portion  53  being approximately 0.10 inches long, and second end portion  54  being approximately 0.30 inches long. 
   To ensure a tight fit over the electrode assembly and over the electrosurgical apparatus, shroud  50  is preferably formed of an elastomeric material. In a preferred embodiment, the elastomeric material is a blue tinted thermoplastic material such as a blue  73  shore A WCPC Dynaflex resin compound available from West Coast Polymers. The resin compound is preferably formed of 49.875% GLS Dynaflex G270I TR65 Shore A, 49.875% GLS Dynaflex G2780 TR82 Shore A (each available from GLS Corporation—Thermoplastic Elastomers Division, McHenry, Ill.) and 0.25% Clariant CPE 06539 TPR Royal Blue (available from Clariant Masterbatches Division, Albion, Mich.). In a preferred embodiment, the shroud is molded over an electrode, as illustrated in  FIG. 6 . It is also contemplated that the shroud may be molded separately from the electrode.  FIG. 6  illustrates an electrode  70  positioned within a clamshell mold  74 . Electrode  70  is restrained from over-insertion into the mold by stop or alignment pin  78 . A predetermined quantity of material for forming shroud  76  is forced through ports within clamshell mold  74  to form shroud  76  on electrode  70 . A mandrel  72  is provided within the mold assembly to form the inner surface of one end portion of shroud  76  such that the end portion has an inner diameter which is greater than the outer diameter of electrode  70 . Pin  78  and sleeve ejector  79 , a stripper plate, function as a pusher to push the shroud  76  and electrode  70  out of the mold assembly once the molding process is complete. 
   Referring again to  FIGS. 4 and 5 , one purpose of the shroud  50  is to prevent over-insertion of the electrode into an electrosurgical instrument while also providing the surgeon with the ability to visually confirm that the electrode is fully seated within the electrosurgical apparatus. Thus, at least the second end portion  54  is preferably formed of a substantially translucent material which will allow the surgeon to visually confirm that the electrode is fully seated within the electrosurgical apparatus. Although second end portion  54  may be formed of a clear material, it is preferred that second end portion  54  is formed of a tinted translucent material. 
   As discussed above, second end portion  54  of shroud  50  is formed of a substantially translucent material. Having at least a portion of shroud  50  formed of substantially translucent material allows the user (i.e., the surgeon, nurse, technician, etc.) to visually ascertain and confirm that electrode  70  is fully and properly coupled to and/or seated within an electrode mounting portion of an electrosurgical apparatus. As such, the uncertainty as to the connection of electrode  70  to the electrosurgical apparatus and/or the incidents of incomplete connection of electrode  70  to the electrosurgical apparatus is reduced. Accordingly, delays in performing the surgical procedure are also reduced thus, on average, tending to reduce the overall time of the surgical procedure. 
   The electrosurgical electrode shroud may further include a visual or tactile indicator on the second end portion for indicating a depth of penetration of the electrosurgical instrument within the second end portion. For example, second end portion  54  may include a circumferential indicator line  56  scribed thereon to provide the surgeon with a reference point against which the surgeon can gauge the depth of penetration of the electrosurgical instrument within the second end portion  54  when the electrosurgical instrument is viewed by the surgeon through the translucent material. Indicator line  56  is preferably set off by arrow  57  formed on transition portion  53 . In addition, a tactile indicator may be added in the shape of a circumferential ring formed on an inner surface of second end portion  54 . As the electrosurgical instrument is inserted into second end portion  54 , the electrosurgical instrument will contact ring thereby providing the surgeon with an indication as to the depth of penetration. 
   Although the illustrative embodiments of the present invention have been described herein with reference to the accompanying drawings, it is to be understood that the invention is not limited to those precise embodiments, and that various other changes and modifications may be affected therein by one having ordinary skill in the art without departing from the scope or spirit of the invention. All such changes and modifications are intended to be included within the scope of the invention as defined by the appended claims.