Abstract:
A surgical access apparatus includes an access member dimensioned for insertion within tissue and having a longitudinal opening to permit introduction of a surgical object through the access member to perform a procedure on underlying tissue. A seal member is mounted across the longitudinal opening of the access member and has an internal portion defining an aperture for forming a substantial seal about the surgical object introduced through the longitudinal opening of the access member. The seal member includes a first seal portion extending from the internal portion and being mounted in suspended relation to the access member, and a second seal portion extending from the internal portion and disposed radially outward of the first seal portion, and being attached to the access member

Description:
CROSS REFERENCE TO RELATED APPLICATIONS  
       [0001]     This application claims priority to U.S. provisional application Ser. No. 60/590,176, filed on Jul. 21, 2004, the entire contents of which are incorporated herein by reference. 
     
    
     BACKGROUND  
       [0002]     1. Technical Field  
         [0003]     The present disclosure relates to a valve system adapted to permit the introduction of surgical instrumentation into a patient&#39;s body. In particular, the present disclosure relates to a valve system for use with an access device which is intended for insertion into a patient&#39;s body, and to receive an instrument in sealing engagement therewith.  
         [0004]     2. Description of the Related Art  
         [0005]     Minimally invasive and laparoscopic procedures generally require that any instrumentation inserted into the body is sealed, i.e., provisions must be made to ensure that gases and/or fluids do not enter or exit the body through an endoscopic incision, such as, for example in surgical procedures where the surgical region is insufflated. For such procedures, the introduction of a tube into anatomical cavities, such as the peritoneal cavity, is usually accomplished by use of a system incorporating a trocar and cannula assembly. Since the cannula is in direct communication with the interior of the peritoneal cavity, insertion of the cannula into an opening in the patient&#39;s body to reach the inner abdominal cavity should be adapted to maintain a fluid tight interface between the abdominal cavity and the outside atmosphere. In view of the need to maintain the atmosphere integrity of the inner area of the cavity, a seal assembly for a cannula, which permits introduction of a wide range of surgical instrumentation and maintains the atmospheric integrity of the inner area of the cavity, is desirable. In this regard, there have been a number of attempts in the prior art to achieve such sealing requirements. A difficulty encountered with conventional seal assemblies, however, is the inability of accommodating the wide range of sizes of instrumentation. In addition, manipulation of instrumentation within the cannula often presents difficulties with respect to maintaining seal integrity.  
       SUMMARY  
       [0006]     Accordingly, the present disclosure provides a seal assembly for an access apparatus, which will allow a surgeon to efficaciously utilize instruments of varying diameter in a surgical procedure. This seal assembly obviates the need for multiple adapters to accommodate instruments of varying diameters by providing a resilient seal member which is mounted in a suspended manner to thereby facilitate insertion and withdrawal of the instrument within an aperture of the seal member.  
         [0007]     In one preferred embodiment, a surgical access apparatus includes an access member dimensioned for insertion within tissue and having a longitudinal opening to permit introduction of a surgical instrument through the access member to perform a procedure on underlying tissue. A seal member is mounted within the access member. The seal member has a distal seal end which is attached to the access member and a proximal seal end. The proximal seal end is longitudinally movable within the access member upon passage of the surgical instrument through the seal member. The seal member preferably has an inner area that defines an aperture disposed between the proximal seal end and the distal seal end for receiving the surgical instrument in substantial sealed relation therewith. The inner area is adapted to be radially displaced to expand the aperture as the surgical instrument is introduced.  
         [0008]     In one preferred embodiment, the proximal seal end of the seal member is disposed radially inwardly of the distal seal end. The distal seal end is connected to the access member along an outer periphery of the distal seal end. Preferably, the proximal seal end defines an outer periphery and an annular member mounted adjacent the outer periphery. The annular member defines a dimension greater than a corresponding dimension of the longitudinal opening of the access member to minimize inversion of the seal member upon withdrawal of the surgical instrument from the seal member.  
         [0009]     The proximal seal end may define a general frusto-conical shape. In the alternative, the proximal seal end includes an undulating portion dimensioned to facilitate passage and/or manipulation of the surgical instrument. The distal seal end defines a general hemispherical shape. In a further alternative, the seal member comprises a cylindrical member folded so that the proximal seal end is disposed within the distal seal end.  
         [0010]     In accordance with another preferred embodiment, a surgical cannula apparatus is disclosed. The cannula apparatus includes a cannula housing, a cannula sleeve extending from the cannula housing and having a longitudinal opening to permit introduction of a surgical instrument and a seal member mounted relative to the cannula housing. The seal member includes a distal seal end, a proximal seal end disposed within the distal seal end, and an inner area interconnecting the proximal and distal seal ends. The inner area defines an aperture for reception of the surgical instrument in substantial sealed relation therewith. The proximal seal end defines an outer periphery adapted for movement relative to the longitudinal axis. The distal seal end defines an outer periphery which is connected to the cannula housing.  
         [0011]     The proximal seal end of the seal member may define a general tapered configuration, e.g., a general frusto-conical configuration. Alternatively, the proximal seal end includes at least one undulation adapted to facilitate movement of the surgical instrument relative to the longitudinal axis.  
         [0012]     The distal seal end of the seal member is dimensioned to extend in a general proximal direction from the inner area. Preferably, the distal seal end is dimensioned to extend in a general proximal direction having longitudinal and radial components of direction. In one embodiment, the distal seal end is generally hemispherical in shape.  
         [0013]     The proximal seal end may include an annular element associated with the outer periphery thereof. The annular element is preferably less compliant than remaining portions of the inner area of the seal member. The cannula housing may include a transverse wall defining an aperture in general alignment with the axis of the cannula sleeve and being disposed proximal of the seal member. The annular element defines a transverse dimension greater than a corresponding transverse dimension of the aperture of the cannula housing such that the annular element is retained distal of the transverse wall during insertion and withdrawal of the surgical instrument thereby minimizing inversion of the seal member.  
         [0014]     In another preferred embodiment, a surgical access apparatus includes an access member dimensioned for insertion within tissue and having a longitudinal opening to permit introduction of a surgical object through the access member to perform a procedure on underlying tissue. A seal member is mounted across the longitudinal opening of the access member and has an internal portion defining an aperture for forming a substantial seal about the surgical object introduced through the longitudinal opening of the access member. The seal member includes a first seal portion extending from the internal portion and being mounted in suspended relation to the access member, and a second seal portion extending from the internal portion and disposed radially outward of the first seal portion, and being attached to the access member.  
         [0015]     A method of providing a seal around a surgical instrument is also disclosed. The method includes the steps of: 
        providing a cannula assembly including an access housing defining a longitudinal axis and a seal having a distal end that is attached to the access housing and a proximal end that is longitudinally movable with respect to the distal end;     engaging the proximal end with the surgical instrument; and     moving the proximal end longitudinally with respect to the distal end so that the seal unfolds.       
 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0019]     The foregoing features of the present disclosure will become more readily apparent and will be better understood by referring to the following detailed description of preferred embodiments, which are described hereinbelow with reference to the drawings wherein:  
         [0020]      FIGS. 1-2  are perspective views of a cannula assembly and a seal assembly in accordance with the principles of the present disclosure;  
         [0021]      FIG. 3  is a side cross-sectional view of the seal assembly in accordance with the embodiment of  FIGS. 1-2 ;  
         [0022]      FIG. 4  is a perspective view of the seal of the seal assembly in accordance with the embodiment of  FIGS. 1-3 ;  
         [0023]      FIG. 5  is a side cross-sectional view of the seal assembly in accordance with the embodiment of  FIG. 4  illustrating insertion of a surgical instrument within the seal assembly;  
         [0024]      FIG. 6  is a side cross-sectional view of the seal assembly in accordance with the embodiment of  FIG. 5  illustrating insertion of a surgical instrument within the seal assembly.  
         [0025]      FIG. 7  is a side cross-sectional view of an alternate embodiment of the seal assembly; and  
         [0026]      FIG. 8  is a side cross-sectional view of the seal assembly in accordance with the embodiment of  FIG. 7  illustrating insertion of a surgical instrument within the seal assembly. 
     
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS  
       [0027]     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 instrument through the cannula assembly. Moreover, the seal assembly of the present disclosure is capable of accommodating instruments of varying diameters, e.g., from 5 mm to 15 mm, by providing a gas tight seal with each instrument when inserted. The flexibility of the present seal assembly facilitates endoscopic surgery where a variety of instruments having different diameters are often needed during a single surgical procedure.  
         [0028]     The seal assembly contemplates the introduction and manipulation of various types of instrumentation adapted for insertion through a trocar and/or cannula assembly while maintaining a fluid tight interface about the instrumentation to preserve the atmospheric integrity of a surgical procedure from gas and/or fluid leakage. Examples of 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”. Alternatively, the seal assembly may be incorporated in a hand access device. A hand access device contemplates the introduction of a hand through the device to assist in performing the surgery. Such hand assisted surgery may be performed in a pressurized environment, e.g., an insufflated abdominal cavity.  
         [0029]     In the following description, as is traditional, the term “proximal” refers to the end of the instrument closest to the operator while the term “distal” refers to the end of the instrument remote from the operator.  
         [0030]     Referring now to the drawings, in which like reference numerals identify identical or substantially similar parts throughout the several views,  FIGS. 1-2  illustrate the seal assembly  100  of the present disclosure mounted to cannula assembly  200 . Cannula assembly  200  may be any conventional cannula suitable for the intended purpose of accessing a body cavity and permit introduction of instruments therethrough. For example, cannula assembly may be similar to the system disclosed in commonly assigned U.S. patent application Ser. No. 10/264,556, filed Oct. 4, 2002, the contents of such disclosure being incorporated by its entirety herein. 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 is a sharp pointed instrument positionable within the passageway of the cannula assembly  200 . The obturator assembly is utilized to penetrate the abdominal wall and then subsequently removed from the cannula assembly to permit introduction of the surgical instrumentation utilized to perform the procedure.  
         [0031]     Cannula assembly  200  includes cannula sleeve  202  and cannula housing  204  mounted to an end of the sleeve  202 . Cannula sleeve  202  defines a longitudinal axis “a” extending along the length of sleeve  202 . Sleeve  202  further defines an internal longitudinal passage  206  dimensioned to permit passage of surgical instrumentation.  
         [0032]     Cannula housing  204  may be a multi-component element secured via a snap fit, ultrasonic welding or any other means envisioned by one skilled in the art including, e.g., adhesive means. Cannula housing  204  may further include diametrically opposed housing grips  208  dimensioned and arranged for gripping engagement by the fingers of the user.  
         [0033]     Cannula housing  204  may further include an internal duck bill or zero closure valve (not shown). Such valve opens to permit passage of the surgical instrumentation and closes in the absence of the instrumentation. The valve may be preferably 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 singer or multiple slit valve arrangements, trumpet valves, flapper valves, etc.  
         [0034]     Cannula sleeve  202  and cannula housing  204  may be formed of stainless steel or other rigid materials such as a polymeric material or the like. Cannula sleeve  202  and/or cannula housing  204  may be clear or opaque. The diameter of sleeve  202  may vary, but typically ranges from 10 to 15 mm to accommodate a range of instrument sizes.  
         [0035]     Referring now the  FIG. 3 , in conjunction with  FIGS. 1-2 , seal assembly  100  will be discussed in detail. Seal assembly  100  includes seal housing, generally identified as reference numeral  102 , and seal  104  disposed within the seal housing  102  in suspended relation therewith. Seal housing  102  houses the sealing components of the assembly and defines central seal housing axis “b” which is preferably parallel to the axis “a” of cannula sleeve  202  and, more specifically, coincident with the axis “a” of the cannula when the seal assembly  100  is mounted to the cannula assembly  100 . In one embodiment, seal housing  102  incorporates two housing components, namely, upper and lower housing components  106 ,  108 , respectively, which, when assembled together, form the seal housing  102 . Assembly of housing components  106 ,  108  may be affected by any of the aforementioned connection means discussed with respect to cannula housing  204 . Alternatively, seal housing  102  may be monolithically formed as a single unit.  
         [0036]     Upper housing component  106  defines outer wall  110  and transverse planar wall  112  disposed between the ends of the outer wall  110 . Transverse planar wall  112  defines central aperture  114  which is preferably coaxially arranged relative to housing axis “b”. Central aperture  114  defines a diameter sufficient to accommodate the largest-diameter instrument contemplated for insertion within seal housing  102 . Transverse planar wall  112  defines an annular recess  116  in its lower surface disposed about central aperture  114 .  
         [0037]     Lower housing component  108  includes inner wall  118  depending upwardly from transverse base  120  of the lower housing component  108 , and first and second outer walls  122 , 124  arranged to depend downwardly relative to the base  120 . Inner wall  118  is preferably correspondingly dimensioned to be received within outer wall  110  of upper housing component  106  and form an interference or friction fit to mount upper and lower housing components  106 ,  108 . Similarly, first outer wall  122  of lower housing component  108  may receive a wall of cannula housing  204  and form a friction fit to secure seal housing  102  to cannula housing  204 . Other means to mount seal housing  102  and cannula housing  204  are envisioned including a bayonet lock, snap fit, adhesives etc. Lower housing component  108  further includes internal tapered wall  126  extending from base  120  and tapering radially inwardly relative to seal housing axis “b”.  
         [0038]     With reference now to  FIGS. 3-4 , suspended seal  104  includes outer or distal seal end  128  and inner or proximal seal end  130  disposed at least partially within the distal seal end  128 . Suspended seal  104  defines internal seal area  132  ( FIG. 3 ) which connects distal and proximal seal ends  128 ,  130  and defines central seal aperture  134 . Distal seal end  128  defines an outer peripheral flange  136 . Outer flange  136  is trapped between planar wall  112  of upper housing component  106  and inner wall  118  of lower housing component  108  to mount seal  104  within seal housing  102  in a suspended manner. Distal seal end  128  extends radially inwardly from outer flange  136  to internal seal area  132  of seal  104 . More specifically, distal seal end  128  has both a transverse and longitudinal component of direction and preferably defines an arcuate, hemispherical or bell shape as shown. Distal seal end  128  may have any elongated configuration including frusto-conical, hourglass, etc. Seal  104  is desirably shaped to form seal aperture  134  which is dimensioned less than the diameter of the instrument, or smallest of the range of instrument sizes to be used with cannula assembly  200 .  
         [0039]     Proximal seal end  130  extends upwardly from internal seal area  132  where it terminates in washer  138 . Proximal seal end  130  is shown as being generally frusto-conical in shape. However, proximal seal end  124  may assume any other configuration including hemispherical, bell shaped, hourglass, etc., i.e., proximal seal end  130  has both a transverse end longitudinal component of direction. Proximal seal end  130  may be a planar or disc-shaped seal.  
         [0040]     Washer  138  is embedded or connected to the upper end of proximal seal end  128 . Attachment of washer  138  to the upper end may be effected by any means including adhesives, cements or the like. Alternatively, washer  138  may be molded within seal  104  to be embedded within proximal seal end  130  during manufacture of the seal  104 . Washer  138  is movably disposed within seal housing  102  and is desirably not attached or connected to upper housing component  106  or any other structure of seal housing  102 . Accordingly, washer  138  and proximal seal end  130  may move in a longitudinal direction “L” ( FIG. 3 ) either toward or away from cannula sleeve  202  during respective introduction or removal of the instrument. This movement of washer  138  facilitates the insertion and removal of the surgical instrument. The diameter of washer  138  preferably approximates, or is greater than, the inner diameter of central aperture  114  of planar wall  112 . Through this dimensioning, washer  138  is prevented from passing through central aperture  114  during withdrawal of the instrument thus preventing inversion of seal  104 . Washer  138  is accommodated within annular recess  116  of transverse planar wall  112  of upper housing component  106  when in an initial condition shown in  FIG. 3 . Washer  138  is preferably formed of a material less compliant than seal member  102  and may be a rigid polymeric material or metallic material.  
         [0041]     Seal  104  of seal assembly  100  preferably comprises a resilient material in at least the region of internal seal area  130  to form a substantial seal about an instrument inserted through seal aperture  134 . Seal  104  may be monolithically formed or composed of several components interconnected to each other. In one preferred embodiment, seal  104  comprises an elastomeric material, which may comprise, e.g., a silicon rubber. In another embodiment, seal  104  includes a resilient elastomer (e.g., polyisoprene or natural rubber) and has a layer of fabric impregnated on each surface of the resilient seal  104 . The fabric may be of any suitable fabric for example, a SPANDEX material containing about 20% LYCRA and about 80% NYLON available from Milliken. A suitable seal member or seal type is disclosed in commonly assigned U.S. Pat. No. 6,702,787 to Racenet et al. and/or U.S. Pat. No. 6,482,181 to Racenet et al., the entire contents of each disclosure being incorporated herein by reference.  
         [0042]     Although seal  104  is disclosed as an impregnated fabric arrangement, it is appreciated that other seal types may be used and still achieve the objectives of the present disclosure. For example, seal  104  may be fabricated from an elastomeric material without the embedded fabric. Gel, foams, or other fluid-filled bladder seal arrangements are also envisioned.  
         [0043]     Seal housing  102  further includes a second seal  140  at least partially received within channel  142  of lower housing component  108 . Second seal  140  engages cannula housing  204  upon mounting of seal housing  102  to the cannula housing  204  to form a substantial seal at this interface thereby substantially eliminating undesired passage of insufflation gas at this interface.  
         [0044]     The use of the seal assembly  100  and cannula assembly  200  in connection with introduction of a surgical instrument will be discussed. Seal assembly  100  is mounted to cannula assembly  200  which is previously introduced into an insufflated abdominal cavity. An instrument  1000  is inserted into seal assembly  100  through aperture  114  of seal housing  102 . As best depicted in  FIG. 5 , the instrument  1000  engages proximal seal end  130 . As best depicted in  FIG. 6 , the force applied by the instrument causes proximal seal end  130  and, possibly, to some extent, distal seal end  128 , to be displaced toward cannula sleeve  202 . During this movement, washer  138 , which can move in the distal direction, may also move downwardly in a longitudinal direction within seal housing  102 . As indicated by the directional arrow “U” in  FIG. 6 , seal  104  unrolls as proximal seal end  130  moves within seal housing  102  to accommodate the instrument. In so doing, aperture  134  enlarges. In addition, internal seal area  132 , which defines central seal aperture  134  of seal  104 , stretches to accommodate the instrument diameter, as necessary to form a seal about the instrument  1000 . The instrument  1000  passes further distally into the cannula housing  204  passing through the duckbill valve (not shown) and cannula sleeve  202  into the body cavity. The surgeon performs the desired operation procedure. After the surgery is completed, the surgeon withdraws the instrument. During withdrawal of the instrument, seal  104  is prevented from inverting due to engagement of washer  138  with planar wall  112 .  
         [0045]      FIG. 7  illustrates an alternate embodiment of the present disclosure. This embodiment is substantially similar to the embodiment of  FIG. 3 ; however, with this embodiment, seal  150 , at an at rest or initial position, defines a plurality of folds  152  within at least proximal seal end  154  as depicted in  FIG. 7 . Accordingly, these folds  152  unravel or roll during introduction of the instrument to, e.g., assume the arrangement (e.g., relatively linear arrangement) of seal  102  depicted in  FIG. 8 . The unfolding of proximal seal end  154  significantly enhances passage and manipulation of the instrument within cannula sleeve  102  by e.g., reducing the initial forces necessary to remove the instrument. Likewise, during withdrawal of the instrument, proximal seal end  154  may fold upon itself or roll to return to the configuration of  FIG. 7  to facilitate removal of the instrument by reducing the initial forces necessary to remove the instrument through aperture  156  of seal  102 . As noted, washer  138  prevents inversion of seal  150  upon withdrawal of the instrument. A further feature of this embodiment is provision of chamfered surface or cut-out  158  on the lower side of planar wall  112 . Chamfered surface  158  serves to guide washer  138  into alignment with the seal axis “b” during removal of the instrument. As a further alternative, it is envisioned that washer  138  may be secured to the underside of planar wall  112  whereby only the central areas of proximal and distal seal ends displace in the longitudinal direction during insertion and removal of the instrument.  
         [0046]     In a further embodiment, the seal comprises an elastomeric material formed in the shape of a cylinder. The cylindrical seal is folded into the conical shape shown in  FIG. 3  and both ends are connected to seal housing  102 . The upper end of the cylindrical seal is resiliently attached to seal housing  102  so that the upper end can move longitudinally with respect to the lower end of the seal and so that the seal can unravel or unfold, as discussed above. The upper end of the cylindrical seal may include washer  138 , as discussed above. In another embodiment, the upper end of the cylindrical seal is captured within a groove in the seal housing so that the upper end can move longitudinally.  
         [0047]     While the invention has been particularly shown, and described with reference to the preferred embodiments, it will be understood by those skilled in the art that various modifications and changes in form and detail may be therein without departing from the scope and spirit of the invention. Accordingly, modifications such as those suggested above, but no limited thereto, are to be considered within the scope of the invention.