Abstract:
A surgical access apparatus for passing through tissue to an underlying surgical area includes an access member defining a longitudinal axis and having a longitudinal channel for reception of a surgical object, a seal member mounted to the access member and positioned to intersect the longitudinal channel, and having internal seal surfaces defining a passage and being dimensioned to establish a substantial sealing relation with a surgical object inserted therethrough and a substantially annular element mounted to the seal member and at least partially circumscribing the passage. The annular member is rigid relative to the seal member and defines an opening to permit passage of the object. The annular element is dimensioned to minimize offset manipulation of the surgical object relative to the longitudinal axis.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     The present application claims the benefit of and priority to U.S. Provisional Application Ser. No. 61/175,924 filed on May 6, 2009, the entire contents of which are incorporated herein by reference. 
    
    
     TECHNICAL FIELD 
     The present disclosure relates to surgical devices and, more particularly, relates to a seal assembly for use with a surgical access device during a minimally invasive surgical procedure, for example, in both laparoscopic and endoscopic procedures. 
     DESCRIPTION OF ART 
     Minimally invasive surgical procedures avoid open invasive surgery in favor of closed or local surgery with less trauma. These procedures involve use of laparoscopic devices and remote-control manipulation of instruments with indirect observation of the surgical field through an endoscope or similar device, and are carried out through the skin or through a body cavity or anatomical opening. Laparoscopic and endoscopic procedures generally require that any instrumentation inserted into the body be sealed, i.e. provisions must be made to ensure that gases do not enter or exit the body through the incision as, for example, in surgical procedures in which the surgical region is insufflated. These procedures typically employ surgical instruments which are introduced into the body through a cannula. The cannula has a seal assembly associated therewith and provides a substantially fluid tight seal about the instrument to preserve the integrity of the established air or gas within the surgical region. 
     Minimally invasive procedures have several advantages over traditional open surgery, including less patient trauma, reduced recovery time, reduced potential for infection, etc. However, minimally invasive surgery, such as laparoscopy, has several disadvantages. In particular, the frictional forces exerted on surgical instruments inserted through it, has proved to be difficult in procedures requiring extensive manipulation of the long narrow endoscopic instruments within a remote site because of the restricted mobility. In addition, known seal devices are deficient in resilience and in rigidity for affixing the seal within a cannula or trocar housing. 
     SUMMARY 
     The present disclosure relates to a surgical access apparatus for passing through tissue to an underlying surgical area. The apparatus includes an access member defining a longitudinal axis and having a longitudinal channel for reception of a surgical object, a seal member mounted to the access member and positioned to intersect the longitudinal channel, and having internal seal surfaces defining a passage and being dimensioned to establish a substantial sealing relation with a surgical object inserted therethrough and a substantially annular element mounted to the seal member and at least partially circumscribing the passage. The annular member is rigid relative to the seal member and defines an opening to permit passage of the object. The annular element is dimensioned to minimize offset manipulation of the surgical object relative to the longitudinal axis. 
     The annular element may be at least partially embedded within the seal member. The annular element is mounted in a radial outward relation to the internal seal surfaces of the seal member whereby the internal seal surfaces engage the surgical object in substantial sealed relation therewith. The annular element may be substantially planar and arranged in general transverse relation to the longitudinal axis. 
     The seal member may define a generally tapered configuration. In this embodiment, the seal member may define a proximal seal face and a distal seal face with the proximal seal face at least partially defining the internal seal surfaces. The annular element may be mounted between the proximal seal face and the distal seal face. In the alternative, the seal member may define a substantially planar configuration. The seal member may comprise an elastomeric material and a fabric material. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Various embodiments of the present disclosure will be described hereinbelow with reference to the figures wherein: 
         FIG. 1  is a perspective views of an access assembly and a seal assembly in accordance with the principles of the present disclosure; 
         FIG. 2  is a side cross-sectional view of the seal assembly; 
         FIG. 3  is an isolated cross-sectional view of the seal member of the seal assembly; 
         FIG. 4  is a cross-sectional view taken along the lines  4 - 4  of  FIG. 3 ; and 
         FIG. 5  is a side cross-sectional view of an alternate embodiment of the seal member of the seal assembly. 
     
    
    
     DETAILED DESCRIPTION 
     The seal assembly of the present disclosure, either alone or in combination with a seal system internal to a cannula assembly, provides a substantial seal between a body cavity of a patient and the outside atmosphere before, during and after insertion of an object through the cannula assembly. Moreover, the seal assembly of the present disclosure is capable of accommodating objects of varying diameters, e.g., instruments from about 4.5 mm to about 15 mm, while maintaining a fluid tight interface about the instrumentation adapted for insertion through a trocar and/or cannula assembly to prevent gas and/or fluid leakage so as to preserve the atmospheric integrity of a surgical procedure. The flexibility of the present seal assembly greatly facilitates endoscopic and/or laparoscopic surgery where a variety of instruments having differing diameters are often needed during a single surgical procedure. Specifically, the surgical device includes a seal assembly which permits and limits some lateral and/or angular manipulation of the surgical instrument while also maintaining a seal about the instrument. The seal assembly is further adapted to substantially close in the absence of a surgical instrument to maintain the integrity of the insufflated peritoneal cavity. 
     The surgical seal assembly of the present disclosure is additionally adapted to decrease the frictional forces exerted on surgical instruments inserted through it which has proven to be difficult in procedures requiring extensive manipulation of the long narrow endoscopic instruments within a remote site because of the restricted mobility. 
     Examples of surgical instrumentation include clip appliers, graspers, dissectors, retractors, staplers, laser probes, photographic devices, endoscopes and laparoscopes, tubes, and the like. Such instruments will be collectively referred to herein as “instruments” or “instrumentation”. 
     The seal assembly may also be adapted dimensionally to receive and form a seal about a physician&#39;s arm or hand during a hand-assisted laparoscopic procedure. In this application, the seal assembly is a component of an access member which is introduced within the body to provide access to underlying tissue in, e.g., the abdominal cavity. 
     Moreover, the seal assembly may be readily incorporated into an access device, such as a conventional trocar device or cannula housing to provide the device with zero-closure and/or sealing around an instrument or other object. 
     In the following discussion, the term “proximal” or “trailing” will refer to the portion of the surgical device nearest to the clinician during operation while the term “distal” or “leading” will refer to that portion of the portal apparatus most remote to the clinician. 
     Referring now to the drawings, in which like reference numerals identify identical or substantially similar parts throughout the several views,  FIGS. 1-2  illustrate one embodiment of a seal assembly, i.e. seal assembly  100  of the present disclosure mounted to an access device such as cannula or trocar assembly  200 . Cannula assembly  200  may be any conventional cannula suitable for the intended purpose of accessing a body cavity and typically defines a passageway permitting introduction of instruments therethrough. Cannula assembly  200  is particularly adapted for use in laparoscopic surgery where the peritoneal cavity is insufflated with a suitable gas, e.g., CO 2 , to raise the cavity wall from the internal organs therein. Cannula assembly  200  is typically used with an obturator assembly (not shown) which may be blunt, a non-bladed, or a sharp pointed instrument positionable within the passageway of the cannula assembly  200 . The obturator assembly is utilized to penetrate the abdominal wall or introduce the cannula assembly  200  through the abdominal wall, and then subsequently is removed from the access device to permit introduction of the surgical instrumentation utilized to perform the procedure through the passageway. Cannula assembly  200  includes cannula sleeve  202  and cannula housing  204  mounted to an end of the sleeve  202 . Any means for mounting cannula sleeve  202  to cannula housing  204  are envisioned including threaded arrangements, bayonet coupling, snap-fit arrangements, adhesives, etc. Cannula sleeve  202  and cannula housing  204  may be integrally formed. Cannula sleeve  202  defines a longitudinal axis “k” extending along the length of sleeve  202 . Sleeve  202  further defines an internal longitudinal passage  206  dimensioned to permit passage of surgical instrumentation. Sleeve  202  may be formed of stainless steel or other rigid materials such as a polymeric material or the like. Sleeve  202  may be clear or opaque. The diameter of sleeve  202  may vary, but, typically ranges from about 10 mm to about 15 mm for use with the seal assembly  100  of the present disclosure. 
     Cannula housing  204  includes luer connector  208 . Luer connector  208  is adapted for connection to a supply of insufflation gaseous is conventional in the art and incorporates valve  210  to selectively open and close the passage of the luer connector  208 . Cannula housing  204  may further include a duckbill or zero closure valve (not shown) adapted to close upon exposure to the forces exerted by the insufflation gases in the internal cavity. Other zero closure valves are also contemplated including single or multiple slit valve arrangements, trumpet valves, flapper valves, etc. 
     With reference to  FIGS. 2-3 , seal assembly  100  will be discussed in detail. Seal assembly  100  may be a separate component from cannula assembly  200  and, accordingly, adapted for releasable connection to the cannula assembly  200 . Alternatively, seal assembly  100  may be incorporated as part of cannula assembly  200 . Seal assembly  100  includes a seal housing, generally identified as reference numeral  102 , and seal member  104  which is disposed within the seal housing  102 . Seal housing  102  houses the sealing components of the assembly and defines the outer valve or seal body of the seal assembly  100 . Seal housing  102  defines central seal housing axis “b” which is preferably parallel to the axis “k” of cannula sleeve  202  and, more specifically, coincident with the axis “k” of the cannula sleeve  202 . Seal housing  102  incorporates three housing components, namely, first, second and third housing components  106 ,  108 ,  110 , respectively, which, when assembled together, form the seal housing  102 . Assembly of housing components  106 ,  108 ,  110  may be affected by any of the aforementioned connection means discussed with respect to cannula housing  204 . 
     Seal member  104  may be mounted within seal housing  102  by any conventional means. In one embodiment, seal member  104  includes an outer peripheral segment  112  which is otherwise attached, mounted or connected to seal housing  102 . Outer peripheral segment  112  may or may not have an undulation to permit lateral movement of seal member  104  within the seal housing  102 . Outer peripheral segment  108  may be secured to seal housing  102  by any conventional means. 
     Seal member  104  defines a general tapered configuration having a longitudinal component of direction with respect to seal axis “b”. Seal member  104  may include an elastomeric material  114  having one or more fabric layers  116  impregnated or mounted to the elastomeric material. A suitable seal  104  is the seal disclosed in commonly assigned U.S. Pat. No. 6,702,787 to Racenet, the entire contents of which are incorporated herein by reference. Fabric layer or material  116  may be, for example, a SPANDEX material containing 20% LYCRA available from Milliken. The elastomeric material may be polyisoprene or a natural rubber. In the embodiment shown in  FIG. 2 , two fabric layers  116  are arranged to enclose elastomeric material  114 . Other arrangements are also envisioned. 
     Seal member  112  has inner seal surfaces  118  which define a passage  120  for passage of the surgical object. The passage  120  may be normally closed or may be in the form of an aperture which is open in at rest condition. Inner seal surfaces  118  adjacent passage  120  may be elastomeric to facilitate formation of the seal about the inserted object. Seal member  112  defines proximal seal face  122 , distal seal face  124  and intermediate seal face  126  disposed between the proximal and distal seal faces  122 ,  124 . Inner seal surfaces  118  establish a seal about the inserted object. Inner seal surfaces  118  may include portions of proximal seal face  122  and intermediate seal face  126 . 
     Seal member  112  has a substantially annular element or ring  128  mounted to or embedded within the seal member  112  adjacent passage  120 . Annular element  128  may be formed from any suitable material which is rigid relative to the elastomeric material of inner surfaces  118 . Suitable materials include polymeric materials, steel, titanium, etc. Annular element  128  defines an opening  130  for passage of the surgical object. Opening  130  generally defines an internal dimension or diameter which is greater than the diameter of the surgical object or instrument to be positioned within cannula sleeve  202 . Annular element  128  may further include anchoring elements  132  depending from the proximal face of the annular element  128 . Anchoring elements  132  may be embedded within seal member  112  to secure annular element  128  to the seal member  112 . Anchoring elements  132  may be embedded during a molding process utilized in manufacturing seal member  112 . In the alternative, annular element  128  may be devoid of anchoring elements  132 , and secured to seal member  112  through adhesives, cements, etc. 
     In the embodiment of  FIGS. 2-4 , annular element  128  is mounted to intermediate end face  126  of seal member  112 . The width “w” of annular element  128  may be less than the corresponding width of intermediate end face  126  of seal member  112 . With this arrangement, the inserted instrument will contact the seal member  112 , e.g., the elastomeric material and/or the fabric material, at inner seal surfaces  112  whereby a seal is formed about the instrument. The instrument or object may move in a lateral direction however, the presence of annular element  128  will ensure that the passage does not open beyond a predetermined inner diameter, e.g., corresponding to the internal dimensions “m” of the annular element  128 . This minimizes the potential of “cat-eyeing”, which is the establishment of a gap between the object and the seal. 
     Seal assembly  100 , either alone or in combination with a seal unit/seal assembly internal to cannula assembly  200 , provides a substantial seal between a body cavity of a patient and the outside atmosphere both during and subsequent to insertion of an instrument through the cannula. In this manner, insufflation gases are prevented from escaping through the trocar assembly to the outside environment. Seal assembly  100  is preferably detachably mountable to cannula housing  204 . Thus, the surgeon can remove the seal assembly  100  from the cannula assembly  200  at any time during the surgical procedure and, similarly, mount the seal assembly  100  to the cannula when desired in order to provide a sealing engagement with an instrument to be inserted through the cannula. In addition, seal assembly  100  may be readily adapted for mounting to conventional cannulas of differing structures. The detachability of seal assembly  100  from cannula assembly  200  facilitates specimen removal through cannula assembly  200 . 
     Referring to  FIG. 5 , an alternate embodiment of seal member  150  for use with the seal assembly  100  is illustrated. Seal member  150  is substantially similar to seal member  104  of the embodiment of  FIGS. 1-4 . Seal member  150  includes inner planar seal segment  152  and outer segment  154 . Inner planar segment  152  has inner seal surfaces  156  defining slit  158  for reception of an object whereby the inner seal surfaces  156  establish a seal about the object. Slit  158  may open for reception of the object and may close in the absence of the object. Thus, seal member  150  also may function as a zero closure valve for maintaining the integrity of the underlying insufflated body cavity. Seal member  150  may, in the alternative, have an aperture in lieu of slit  158 . Inner planar segment  152  has proximal and distal faces  160 ,  162 . 
     Seal member  150  further includes annular element  164  mounted to distal face  162 . Annular element  164  may be substantially similar to the annular element  128  discussed hereinabove in connection with the embodiment of  FIGS. 1-4 . Annular element  164  defines an internal dimension “t” greater than an internal dimension of slit  158 . Annular element  164  restricts lateral movement of the surgical object thereby assisting in maintaining the integrity of the seal about the object by, e.g., minimizing “cat-eyeing”. In addition, in the event the object is moved laterally or in a radial direction, the forces associated with this movement are transferred to the outer peripheral segment of seal member  150 . This may preserve the integrity of inner seal surfaces  156  defining slit  158 . 
     It will be understood that various modifications may be made to the embodiments shown herein. Therefore, the above description should not be construed as limiting, but merely as exemplifications of preferred embodiments. Those skilled in the art will envision other modifications within the scope and spirit of the presently disclosed seal assemblies.