Abstract:
A cannula assembly includes a housing and a cannula member connected to the housing. The cannula member has leading and trailing ends and defines a longitudinal axis. The cannula member further includes a main body, a seal adjacent the leading end and a flexible portion disposed between the main body and the seal. The seal is capable of receiving an instrument therethrough while maintaining a substantial sealed relation with the instrument. The flexible portion is configured to permit movement of the seal relative to the longitudinal axis during manipulation of the endoscopic instrument. The flexible portion of the cannula member may include one or more bellows. The one or more bellows may form a goose neck configuration. Alternatively, the one or more bellows define a series of ridges and grooves.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     The present application claims the benefit of and priority to U.S. Provisional Application Ser. No. 60/930,745 filed on May 18, 2007, the entire contents of which are incorporated herein by reference. 
    
    
     BACKGROUND 
     1. Technical Field 
     The present disclosure relates generally to a system for accessing the body, and, more particularly, relates to a cannula having a seal and an associated flexible body portion adapted to permit lateral, angular or longitudinal movement of an inserted instrument while also preserving the sealed relation of the seal about the instrument during its manipulation. 
     2. Background of Related Art 
     Surgical cannulas are employed in various minimally invasive procedures including laparoscopic or endoscopic procedures. Such cannulas each typically incorporate a rigid tubular member and a seal mechanism. The seal mechanism is intended to form a fluid tight seal about an instrument or hand passed through the tubular member. The seal mechanism, however, is often limited by its ability to sustain a seal when an instrument is moved off-axis relative to a central axis of the cannula. Moreover, the seal mechanisms are also limited by their ability to sustain their integrity when the surgical instrument is angulated. Furthermore, due to the rigidity of the tubular member of the cannula, offset manipulation of the inserted instrument is restricted. 
     SUMMARY 
     Accordingly, the present disclosure is directed to a cannula assembly including a housing and a cannula member connected to the housing. The cannula member has leading and trailing ends and defining a longitudinal axis. The cannula member further includes a main body, a seal adjacent the leading end and a flexible portion disposed between the main body and the seal. The seal is capable of receiving an instrument therethrough while maintaining a substantial sealed relation with the instrument. The flexible portion is configured to permit movement of the seal relative to the longitudinal axis during manipulation of the endoscopic instrument. The flexible portion of the cannula member may include one or more bellows. The one or more bellows may form a goose neck configuration. Alternatively, the one or more bellows define a series of ridges and grooves. 
     The flexible portion is adapted to permit angular movement of the seal relative to the longitudinal axis. The flexible portion may be adapted to permit lateral movement of the seal relative to the longitudinal axis. The flexible portion may be adapted to permit lateral and angular movement of the seal relative to the longitudinal axis. The flexible portion may be adapted to permit longitudinal movement of the seal relative to the longitudinal axis. 
     The seal may be adapted to substantially close in the absence of an instrument. 
     In another embodiment, the cannula includes a cannula member defining a central axis and having proximal and distal ends. The cannula member includes a main body adjacent the proximal end of the cannula member, a universal seal adjacent the distal end of the cannula member and a generally flexible portion disposed between the main body and the universal seal. The universal seal may be adapted to form a substantial sealed relation about a surgical object advanced through the cannula member and is further adapted to substantially close in the absence of the surgical object. The flexible portion may be adapted to permit movement of the universal seal relative to the central axis upon manipulation of the surgical object. The flexible body portion may define at least one bellows. The flexible body portion may comprise an elastomeric material. The flexible body portion may be adapted to permit lateral movement of the universal seal relative to the central axis. The flexible body portion may be adapted to permit angular movement of the universal seal relative to the central axis. The flexible portion may be adapted to permit each of angular and lateral movement of the universal seal relative to the central axis. In the alternative, the flexible portion is adapted to permit longitudinal movement of the seal relative to the longitudinal axis. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Preferred embodiments of the present disclosure are described hereinbelow with references to the drawings, wherein: 
         FIG. 1  is a side view of a trocar cannula according to an embodiment of the present disclosure; 
         FIG. 2  is a side view of the distal end of the trocar cannula of  FIG. 1  illustrating an endoscopic instrument introduced therein; 
         FIG. 3  is a side cross-sectional view of the distal end of the trocar cannula illustrating an instrument at least partially therein and the seal in a closed position; 
         FIG. 4  is a side cross-sectional view of the distal end of the trocar cannula illustrating the instrument advanced through the seal; 
         FIG. 5  is an enlarged section of the flexible portion of the trocar cannula; 
         FIG. 6  is an axial view of the trocar cannula illustrating the seal in a closed position; 
         FIG. 7  is an axial view of the trocar cannula illustrating the endoscopic instrument inserted through the seal; 
         FIGS. 8-9  are side cross-sectional views of the distal end of the trocar cannula illustrating a range of offset angulated motion of the endoscopic instrument within the trocar cannula; 
         FIGS. 10-11  are side cross-sectional views of the distal end of the trocar cannula illustrating a range of offset lateral motion of the endoscopic instrument within the trocar cannula; 
         FIG. 12  is a side cross-sectional view of another embodiment of the present disclosure; and 
         FIG. 13  is an enlarged cross-sectional view of the flexible portion of the trocar cannula of  FIG. 12 . 
     
    
    
     DETAILED DESCRIPTION 
     The cannula of the present disclosure is capable of accommodating objects of varying diameters, e.g., including instruments from about 4.5 millimeter (mm) to about 15 millimeter (mm), during a minimally invasive surgical procedure. Moreover, the cannula 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 prevent gas and/or fluid leakage from the established pneumoperitoneum so as to preserve the atmospheric integrity of a surgical procedure. Specifically, the cannula includes a flexible body portion and associated distal seal which permits angular manipulation of the surgical instrument while maintaining or preserving the sealing relation formed by the seal about the instrument. This feature of the present disclosure desirably minimizes the entry and exit of gases and/or fluids to/from the body cavity and also provides enhanced capability of instrument manipulation within the operative site. 
     Examples of instrumentation contemplated for use with the cannula 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”. 
     In the following discussion, the term “proximal” will refer to the portion of the access apparatus nearest to the clinician during operation while the term “distal” will refer to that portion of the access 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,  FIG. 1  illustrates the trocar cannula of the present disclosure. Cannula  100  may be any member suitable for the intended purpose of accessing a body cavity and typically defines a passageway permitting introduction of instruments or the clinician&#39;s hand therethrough. Cannula  100  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  100  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  100 . The obturator assembly is utilized to penetrate the abdominal wall to introduce the cannula  100  through the abdominal wall, and then subsequently is removed from the cannula  100  to permit introduction of the surgical instrumentation utilized to perform the procedure through the passageway. 
     Referring initially to  FIGS. 1 and 2 , cannula  100  includes housing  102  and cannula member  104  extending distally from the housing  102 . Either or both housing  102  and cannula member  104  may be transparent in part or in whole and may be fabricated from biocompatible metal or polymeric material. Housing  102  typically incorporates at least one internal seal which is adapted to form a fluid tight seal about an instrument inserted through the housing  102 . One suitable seal may be the fabric seal disclosed in commonly assigned U.S. Pat. No. 6,702,787, which issued Mar. 9, 2004, the entire contents of which are incorporated herein by reference. The seal disclosed in the &#39;787 patent may be a flat septum seal having a first layer of resilient material and a second fabric layer juxtaposed relative to the first layer. Further details of the seal may be ascertained by reference to the &#39;787 patent. Housing  102  may include an internal seal such as a duck-bill valve or other zero closure valve adapted to close in the absence of a surgical instrument to prevent passage of insufflation gases through the housing  102 . In one embodiment of the present disclosure, however, trocar cannula  100  is devoid of either or both an internal seal and a zero closure valve. 
     With reference now to  FIGS. 1-4 , cannula member  104  includes main body  106  adjacent housing  102 , flexible portion  108  connected to the main body  106  and universal seal  110  which is distal of the flexible portion  108 . Main body  106  may be substantially rigid and defines central longitudinal axis “k”. Alternatively, main body  106  may have some degree of flexibility. 
     Flexible portion  108  is relatively flexible to permit a range of motion of universal seal  110 . Such motion of universal seal  110  is inclusive of angulated motion, lateral motion and/or longitudinal motion with respect to the central longitudinal axis “k”. In one embodiment, flexible portion  108  includes a bellows or goose-neck arrangement defined by at least one or a plurality or series of continuous bellows  112  or alternating convexities/ridges and concavities/recesses. For example, as seen in  FIG. 5 , continuous bellows  112  includes an inner bellows  112   a  and a generally coaxial outer bellows  112   b . Continuous bellows  112  of flexible portion  108  are adapted to angulate, longitudinally extend and/or move laterally relative to each other to permit corresponding movement of universal seal  110  relative to the central longitudinal axis “k” during manipulation of the instrument. 
     Referring now to  FIGS. 3-7 , universal seal  110  will be discussed. Universal seal  110  may be adapted to close in the absence of an instrument to prevent passage of fluids, e.g., insufflation gases therethrough, e.g., to thereby assist in maintaining the integrity of the insufflated body cavity, e.g., the abdominal cavity. Universal seal  110  includes outer portion  114  and inner seal portion  116 . Outer portion  114  is connected to flexible portion  112  of cannula member  104  through conventional means. Outer portion  114  may be composed of an elastomeric material, plastic, polymer, or the like. Outer portion  114  forms a tapered element depending from flexible portion  112  and is arranged to normally bias inner seal portion  116  radially inwardly to the closed position depicted in  FIG. 3 . Outer portion  114  also may bias inner seal portion  116  into a position in general longitudinal alignment with longitudinal axis “k”. Although inner seal portion  116  is shown positioned along longitudinal axis “k”, it is envisioned that the universal seal may be positioned anywhere within the diameter of cannula member  104 , and may or may not be aligned with the longitudinal axis “k” 
     Inner seal portion.  116  is substantially flexible or resilient, and is adapted to form a substantial fluid tight seal about an instrument inserted through the inner seal portion  114 . In a first or initial state, e.g., in the absence of an instrument inserted therethrough, inner seal portion  116  is closed, forming an air-tight seal as effected through the biasing action of, e.g., outer portion  114 . In a second open configuration when an instrument  10  is advanced through inner seal portion  116 , the inner seal portion  116  may stretch or expand to accommodate instrument  10  while maintaining an air-tight seal thereabout. Inner seal portion  116  may be configured such that an increased seal surface area is achieved upon insertion of distal end  12  of instrument  10  therethrough. This increased seal surface area permits nominal manipulation of instrument  10  without compromising the integrity of the air-tight seal. Inner seal portion  116  may be fabricated from an elastomeric material and may be integrally or monolithically formed with outer portion  114  of universal seal  110 . Inner seal portion  116  may define slit  118  adapted to open to permit passage of the instrument  10 . In the alternative, inner seal portion  116  may define an aperture (not shown). 
     Referring to  FIGS. 8 and 9 , as the proximal end (not shown) of instrument  10  is handled or manipulated outside of cannula  100 , any angular movement thereof may be translated to distal end  12  of the instrument. As distal end  12  is angled relative to axis “k” of cannula member  104  through a predetermined angle “b”, bellows  112  of flexible portion  108  extend and/or retract accordingly to permit movement of universal seal  110  with distal end  12  of instrument  10 . In this manner, the a substantial amount of seal surface area of inner seal portion  116  remains in contact about instrument  10  throughout the range of manipulation, thereby ensuring that the integrity of the seal is not compromised. As instrument  10  is angled relative to axis “k” of cannula member  104 , bellows  112  of flexible portion  108  on one side, e.g., the right side extend, while the bellows  112  on the opposed side, e.g., the left side contract. ( FIG. 8 ) The opposite is also true when instrument  10  is angled to the right relative to cannula member  104  ( FIG. 9 ). As can been seen in  FIGS. 8 and 9 , the angle at which instrument  10  may be manipulated with cannula  100  is limited by the length and diameter of cannula member  104 . 
     Referring now to  FIGS. 10 and 11 , flexible portion  108  of cannula  100  may also be configured to permit lateral manipulation of distal end  12  of instrument  10  while maintaining the integrity of the seal thereabout. As the proximal end (not shown) of instrument  10  is moved laterally within cannula  100  relative to axis “k” of cannula member  104 , distal end  12  of instrument  10  may be correspondingly moved with the inner seal portion  114  of universal seal  110  also being shifted in a lateral direction. As distal end  12  of instrument  10  is shifted laterally, bellows  112  of flexible portion  108  extend or stretch to accommodate the lateral movement. In this manner, inner seal portion  116  maintains contact about instrument  10  throughout the range of manipulation, thereby ensuring that the integrity of the seal is not compromised. Both lateral and angular movement of instrument  10  and universal seal  110  is envisioned. 
       FIGS. 11-12  illustrate an alternate embodiment where bellows  112  of flexible portion  108  of cannula member  104  is adapted to permit longitudinal movement of the flexible portion. More specifically bellows  112  may expand and contract in accordion-like manner to increase or decrease the effective length of flexible portion  108  and cannula member  104 . In this embodiment, flexible portion  108  is connected to main body  106  and universal seal  110  via a detent mechanism incorporating radially inward detents  120  of flexible portion  108  which are received within corresponding recesses  122  in main body  106  and the universal seal  110 . Other means for connecting flexible portion to main body and/or universal seal are envisioned. Flexible portion  108  may also move laterally and angularly with respect to longitudinal axis “k” 
     Although the illustrative embodiments of the present disclosure have been described herein with reference to the accompanying drawings, it is to be understood that the disclosure is not limited to those precise embodiments, and that various other changes and modifications may be effected therein by one skilled in the art without departing from the scope or spirit of the disclosure. Other variations are also envisioned, it should be understood that various changes in form, detail and operation of the goose neck cannula of the present disclosure may be made without departing from the spirit and scope of the present disclosure.