Abstract:
In order to provide a surgical clip device with which the closure of vessels is successfully achieved even more safely, particularly in neurosurgery, it is proposed that the surgical clip device be provided with at least two electrically conductive clip parts that are electrically isolated from each other (by an element) and are arranged at a predetermined distance opposite each other.

Description:
This application is a continuation of international application number PCT/EP2011/066125 filed on Sep. 16, 2011 and claims the benefit of German application number 10 2010 037 748.1 filed on Sep. 23, 2010, which are incorporated herein by reference in their entirety and for all purposes. 
    
    
     BACKGROUND OF THE INVENTION 
     The invention relates to a surgical clip device, in particular for closing vessels in neurosurgery. 
     To this end, metallic clips formed in a U-shape or V-shape are widely used, these clips being placed on the vessel with a clip applying forceps and, when deformed through the closing force of the forceps, effecting closure of the vessel concerned. Such clips are known for example from DE 195 20 158 C2. 
     In order to make more secure the closure of a vessel by a clip, so-called double-web clips have already been proposed (cf. for example DE 10 2006 001 344 A1) in which two U-shaped or V-shaped clamps of the clip that are formed integrally with each other and are arranged substantially parallel to each other form two points of closure at the vessel which are located one behind the other in a longitudinal direction of the vessel. 
     It can nevertheless still happen in critical situations that even such a double closure of the vessel does not prevent small leakages, thus still allowing small amounts of blood to leak therefrom. 
     It is an object of the invention to propose a surgical clip device with which the closure of vessels is successfully achieved even more safely, particularly in neurosurgery. 
     SUMMARY OF THE INVENTION 
     This object is attained by a surgical clip device as defined in claim  1 . 
     Accordingly, the surgical clip device constructed in accordance with the invention relies not only on a mechanical closure of the vessel in which the two clip parts in the form of clamp arms, typically constructed of metal, hold the vessel in compression over its cross-section and thus close it shut, but owing to the clip parts or clamp arms being configured so as to be electrically isolated from each other, it is possible, concurrently with the application of the surgical clip device, to initiate a coagulation or sealing process in the area of the clip so that besides the mechanical closure a substance to substance-bonded closure of the vessel is additionally achieved. 
     An additional advantage is evident in that the coagulation and sealing process causes stiffening of the tissue in the coagulation region and as a result of this the clip device is additionally given more firm support. For that purpose, a clip applicator constructed in accordance with the invention is preferably used which will be described in more detail below. 
     The surgical clip device with its two electrically conductive clip parts, in particular clamp arms, arranged in electrical isolation from each other, can be implemented in a wide variety of embodiments. 
     In particular, the clip parts are part of a U-shaped or V-shaped clip configuration, wherein the two clip parts are held at a first end thereof on an electrically isolating holding part, thereby forming the two legs of the U-shaped or V-shaped configuration. 
     Preferably, the electrically isolating holding part is plastically deformable. 
     Typical materials used for the isolating holding parts are plastics materials. 
     Provision is in particular made for the two clip parts to be configured symmetrically with respect to one another, with the electrically isolating holding part being kept as small as possible in order to provide as large a sphere of action as possible for the coagulation process occurring through the electrically conductive clip parts. 
     In particular, the two clip parts are of substantially identical configuration and are arranged in a mirror image relationship with their first end fixed to the electrically isolating holding part. 
     Alternatively, the electrically isolating holding part can be located asymmetrically on the U-shaped or V-shaped clip so that a first clip part or clamp arm comprises the one leg and the central arcuate part, while the electrically isolating holding part and the second clip part or clamp arm form the other leg. Here, the plastic deformation does not inevitably occur on the holding part but takes place primarily on the central arcuate part of the one clip part, which typically consists of a metal material. 
     In a more preferred embodiment of the surgical clip device constructed in accordance with the invention, provision is made for the clip parts or clamp arms to be capable of being connected together at their respective free end opposite the first end thereof by way of an electrically isolating connection. 
     The connection is preferably configured as a latched connection. 
     To this end, it is in particular provided for electrically isolating latch elements to be arranged at the free ends of the clip parts, said latch elements latching into engagement with each other upon mechanical closure of the clip, thus already providing additional mechanical fixing of the clip at the vessel that is to be closed off. 
     As an alternative to the latched connection, provision may also be made for the electrically isolating connection to be a substance to substance-bonded connection forming at the free ends of the clip parts as a result of heat generated during the coagulation and sealing process. 
     In another embodiment of the surgical clip devices constructed in accordance with the invention, provision may be made for two clip parts, each of substantially U-shaped or V-shaped configuration, to be held in parallel alignment with each other and spaced apart at a predetermined distance. For application to a vessel, said two clip parts are grasped by a clip applicator, said clip applicator comprising a gripping tool for the two clip parts having gripping jaws which are electrically isolated from each other. The two clip parts can then be applied to the vessel using the clip applicator, and in the same step a sealing action in the area of the mechanical closure of the vessel can be achieved by a coagulation current. Here, the coagulation procedure results in an additional closure of the vessel that is substance to substance-bonded. 
     The two clip parts may lack any connection to each other and just be held ready in a desired array, for example in a magazine, until received by the gripping tool. After withdrawal from the magazine and until application, the two clip parts are held in an electrically isolated and spaced-apart relationship to each other by the mutually electrically isolated gripping jaws. 
     More preferably, the two clip parts are releasably held in parallel alignment with each other and spaced apart at the predetermined distance in a holding device. In such clip devices constructed in accordance with the invention, the configuration of the gripping jaws of the clip applicator allows for a somewhat simpler design. 
     Alternatively, provision may be made for the two clip parts to be fixedly connected in parallel alignment with each other and spaced apart at the predetermined distance by an electrically isolating holder. The holder in turn can be made of a plastics material. In that case as well, the configuration of the gripping jaws of the clip applicator is simplified. 
     The holder can be of one-piece configuration and for example interconnect the two clip parts at the respective mid-regions thereof. 
     In a more preferred embodiment, the free ends of the two clip parts are in each case connected together by way of an electrically isolating holding part of the holder. 
     More preferably, said two holding parts of the holder can then also be configured in the form of latch elements which latch into engagement with each other when the clip is applied to the vessel. 
     As has already been described above, it may also be provided that, in lieu of the latch elements, electrically isolating holding parts be used that together form a substance-to-substance bond by heat generated during the coagulation and the sealing of the vessel. 
     Also in this case, the free clip ends are fixedly connected to each other, and thus the vessel, besides being mechanically secured by the double clip device as described above, is additionally sealed via the coagulation procedure. 
     The invention further relates to a clip applicator for use with a surgical clip device constructed in accordance with the invention, as described above. 
     The applicator constructed in accordance with the invention comprises a gripping tool having two mutually electrically isolated gripping jaws for the two clip parts, wherein the gripping jaws are capable of being connected to a coagulation current-delivering current source. 
     More preferably, the applicator comprises a magazine having a clip carrier, wherein the clip carrier has a plurality of surgical clip devices arranged thereon as described above. 
     The current source with which the gripping jaws of the applicator can be connected is preferably a high-frequency current source. 
     These and further advantages of the invention are described in more detail below with reference to the drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIGS. 1A, 1B  show two variants of a first embodiment of a surgical clip device constructed in accordance with the invention; 
         FIGS. 2A, 2B  show two variants of a second embodiment of a surgical clip device constructed in accordance with the invention; 
         FIG. 3  illustrates a clip applicator constructed in accordance with the present invention; and 
         FIGS. 4A to 4D  show schematically a sequence of steps in the process of applying a clip device constructed in accordance with  FIG. 2A or 2B . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       FIG. 1A  shows a surgical clip device  10  (hereinafter also referred to as clip) having two electrically conductive clip parts or clamp arms in the form of legs  12  and  14  which are held in a substantially U-shaped arrangement in electrical isolation from each other by a holding part  16  and are held spaced apart at a predetermined distance from each other and in opposed relationship with respect to each other. When the clip  10  is applied to a vessel, the two legs  12  and  14  are urged toward each other from two sides of the vessel and are maintained electrically isolated from each other by way of the holding part  16 . The holding part is fabricated from a plastically deformable plastics material so that applying the clip  10  results in a permanent mechanical closure of the vessel. In the compressed state, a coagulation current is then applied via a gripping tool of an applicator so that the vessel, apart from being mechanically closed shut, is additionally sealed off. 
     The clip device  20  depicted in  FIG. 1B  has asymmetrically configured clamp arms in the form of legs  22 ,  24  and an electrically isolating holding part  26  correspondingly arranged in an off-centre position. 
     When the clip  20  is applied, plastic deformation takes place primarily on an arcuate part  28  integrally formed on the leg  22 , thereby providing for a permanent mechanical closure of the vessel. 
       FIG. 2A  shows a surgical clip device  30  in which two clip parts or clamp arms  32 ,  34 , each of substantially U-shaped configuration, are arranged parallel to each other. These two clip parts can, for example at a mid-region thereof, be joined together, and held in a spaced-apart relationship, by a web  36  made of an electrically isolating material, such as a plastics material. 
     A more preferred clip device, however, is a clip device  40  illustrated in  FIG. 2B  in which two U-shaped clip parts or clamp arms  42 ,  44  are, at their respective free ends  52 , 53 ;  54 , 55 , held in electrically isolated and spaced-apart relationship via two holding parts  46 ,  48 , with the holding part  46  being preferably provided with a latch element  50  that is of hook-shaped configuration in  FIG. 2B  and is connectable to the holding part  48  in a form-locked manner. 
     Alternatively or additionally, provision may be made for the material of the holding parts  46 ,  48  or in particular also of the latch part  50  to be selected such that the heat generated from coagulation of the vessel material is sufficient to effect a substance-to-substance bond between the holding parts  46 ,  48 , in particular between the part designated  50  and the part designated  48 . 
       FIG. 3  illustrates a clip applicator  70  constructed in accordance with the invention, wherein the portion of the handle for operating the applicator  70  is omitted for simplicity. 
     Shown in  FIG. 3  is a shaft  72  of the applicator  70 , said shaft  72  having arranged therein a clip magazine  74  with clips  40  situated in a row one behind the other. The shaft  72  has on its distal end a gripping tool  71  comprising two gripping jaws  76 ,  77  and  78 ,  79  held in electrically isolated relationship from each other and which, when a clip  40  is applied, receive and guide, in receiving grooves  80 ,  81 ;  82 ,  83  thereof, the clip parts  42 ,  44  of the clip  40  with the free ends  52 ,  53 ;  54 ,  55  thereof. 
     Once a clip  40  has been positioned at a vessel using the gripping tool  71 , the gripping jaws  76 ,  77 ;  78 ,  79  can be pivoted relative to one another by a handle (not shown) of the applicator  70  so that the clip  40  is squeezed together, which first results in a double mechanical closure of the vessel; this will be explained in greater detail in conjunction with the schematic drawings of  FIGS. 4A to 4D . 
     Because the gripping jaws  76 ,  77 ;  78 ,  79  of the clip applicator  70  are held in electrically isolated relationship, a current may then be applied to them, and the physical contact established between the free ends of the legs  52 ,  53 ;  54 ,  55  of the clip  40  and the gripping jaws  76 ,  77 ;  78 ,  79  also establishes an electrically conductive contact therebetween so that the electric current can be delivered to the legs of the clip  40 . 
     The sequence of steps for applying a clip device constructed in accordance with the invention is schematically shown in  FIGS. 4A to 4D , taking as an example the clip device  40  constructed in accordance with the invention as illustrated in  FIG. 2B . The procedure applies analogously to the clips of  FIGS. 1A, 1B and 2A . 
       FIG. 4A  is a sectional view of the clip  40  with its legs  52 ,  54  located below a vessel  100  and legs  53 ,  55  located above the vessel  100 . The legs  52 ,  54  are guided and held in grooves  82 ,  83  of the gripping jaws  78 ,  79 , and the legs  53 ,  55  are guided and held in grooves  80 ,  81  of the gripping jaws  76 ,  77 . 
     In the next step, as shown in  FIG. 4B , the gripping jaws  76 ,  77  and  78 ,  79  are moved toward each other, thereby approximating the legs  52 ,  54  and  53 ,  55  toward each other, thereby mechanically closing the vessel  100  in the regions  102  and  104  thereof, said regions  102  and  104  being spaced apart in a longitudinal direction of the vessel. 
     In the closed position of the clip  40 , the part designated  50  then latches into engagement with the holding part  48 , thus securing the closed position of the clip  40 . 
     Subsequently, the gripping jaws  76 ,  78  and  77 ,  79  are connected in pairs to a terminal of a HF current source so that a coagulated region  106  of the vessel  100  then forms between the mechanically closed-off regions  102 ,  104  of the vessel  100  (cf.  FIG. 4C ). 
     As soon as the coagulation procedure is complete, which typically only takes few seconds/the fraction of a second, the gripping jaws  76 ,  77 ;  78 ,  79  are returned to their initial position and the applicator  70  is removed from the vessel  100 . This leaves the vessel  100  with the legs  52 ,  53  and  54 ,  55  of the clip  40  applied to the vessel  100  and mechanically interlocked via the holding parts  46 ,  48 ,  50 , wherein in addition to the double mechanical closure of the vessel  100  in the regions  102 ,  104 , additional safety is provided by a coagulated region  106  ( FIG. 4D ).