Abstract:
A surgical access port and method for achieving triangulation is disclosed, the surgical access port comprising a housing and an articulation structure. The housing is comprised of a cylindrical member having proximal and distal ends, and defining a longitudinal axis. The articulation structure is comprised of at least two lumens, each of the at least two tubular members disposed in a respective lumen, at least two rotating members disposed along each of the at least two tubular members, an actuating member, and a rigid member connecting each rotating member to each tubular member. The tubular members are configured to receive instruments for use in minimally invasive procedures.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims priority to, and the benefit of, U.S. Provisional Patent Application Ser. No. 61,469,008 filed Mar. 29, 2011, the entire contents of which are incorporated by reference herein. 
     
    
     BACKGROUND 
       [0002]    1. Technical Field 
         [0003]    The present disclosure relates generally to a surgical device for use in a minimally invasive surgical procedure. More particularly, the present disclosure relates to a surgical portal device adapted and configured to receive surgical instruments therein, and to reposition the distal ends of the surgical instruments that are placed through the surgical portal device. 
         [0004]    2. Description of Related Art 
         [0005]    Increasingly, many surgical procedures are performed through small incisions in the skin. As compared to the larger incisions typically required in traditional procedures, smaller incisions result in less trauma to the patient. By reducing the trauma to the patient, the time required for recovery is also reduced. Generally, the surgical procedures that are performed through small incisions in the skin are referred to as endoscopic. If the procedure is performed on the patient&#39;s abdomen, the procedure is referred to as laparoscopic. Throughout the present disclosure, the term minimally invasive is to be understood as encompassing both endoscopic and laparoscopic procedures. 
         [0006]    During a typical minimally invasive procedure, surgical objects, such as surgical access devices (e.g., trocar and cannula assemblies) or endoscopes, are inserted into the patient&#39;s body through the incision in tissue. In general, prior to the introduction of the surgical object into the patient&#39;s body, insufflation gas is used to enlarge the area surrounding the target surgical site to create a larger, more accessible work area. Accordingly, the maintenance of a substantially fluid-tight seal is desirable so as to inhibit the escape of the insufflation gases and the deflation or collapse of the enlarged surgical site. In response to this, various access devices with sealing features are used during the course of minimally invasive procedures to provide an access for surgical objects to enter the patient&#39;s body. Each of these devices is configured for use through a single incision or a naturally occurring orifice (i.e. mouth, anus, or vagina) while allowing multiple instruments to be inserted through the device to access the working space beyond the device, generally an internal body cavity. 
         [0007]    During procedures employing multiple surgical instruments through a single incision access device, it is advantageous to determine the position of the end effectors relative to each other and/or relative to a fixed reference point. This is desirable when one or more of the instruments includes an end effector that is articulable relative to the surgical instrument. Identifying the position of each end effector relative to the other end effectors and/or a common reference point is advantageous during a surgical procedure. 
         [0008]    Some disadvantages of minimally invasive procedures include a lack of direct visualization of the surgical site and reduced dexterity of instruments, as compared to traditional open surgeries. 
         [0009]    One surgical technique used to increase the ability of the surgeon to visualize and access critical anatomy is triangulation. Triangulation is a principle in which the positioning of the surgical instruments may be determined by having known initial positions of the instruments with respect to a given point, e.g., another device or instrument, and tracking the change in position from that initial position. One method of triangulation involves holding surgical instruments so that their tips form the apex of an imaginary triangle. By knowing the initial positions of surgical instruments with respect to a given point and by tracking the change in position, the coordinates of the surgical instruments are determinable. 
         [0010]    One example, as disclosed by US Patent Application Pre-Grant Publication US2005/0234294, uses an articulating element disposed near a distal region and pivotally coupled to hinges by linkages. 
         [0011]    Another example, as disclosed by US Patent Application Pre-Grant Publications US2007/0167680 and US2008/0051631, uses a rod connected to linking members which spread a set of arm members containing surgical devices apart when the rod is actuated. 
         [0012]    Another example, as disclosed by US Patent Application Pre-Grant Publication US2008/0188868, uses a collar, a wedge, a balloon or bands to help maintain a divergence between the surgical devices. 
         [0013]    Yet another example, as disclosed by U.S. Pat. Nos. 5,318,013; 5,395,367; and 5,511,564, uses an actuator including an articulated linking comprising a pair of arms pivotably connected to a push rod and to shafts of respective grasping forceps to enable relative spreading of the grasping forceps from a straightened or mutually parallel configuration to a spread use configuration. 
         [0014]    In conventional minimally invasive surgical procedures, triangulation is achieved through insertion of multiple instruments through multiple openings. In most minimally invasive surgical procedures through a single incision, straight and rigid surgical instruments are inserted through a single incision. To control the instruments, a surgeon often crosses his hands. The lack of triangulation makes visualization and access of critical anatomy potentially difficult. 
         [0015]    Furthermore, the placement of multiple instruments through a single incision increases the potential of interference among those instruments. It would be advantageous to space those instruments apart within the surgical site, without necessitating a larger incision. 
         [0016]    Consequently, a continuing need exists for improved minimally invasive surgical devices. 
       SUMMARY 
       [0017]    The present disclosure relates to surgical access ports for use in minimally invasive procedures where articulation of instruments disposed in a body cavity is required to reach off-axis points within the body cavity and determine the relative positioning of end effectors of surgical instruments disposed through the surgical access ports. 
         [0018]    According to one embodiment of the present invention, a surgical access port is provided which includes a housing, at least two lumens extending through the housing, and an articulation structure disposed in the surgical access port. The housing is comprised of a cylindrical member having proximal and distal ends, and defining a longitudinal axis. Each lumen has an entrance aperture in the proximal end of the housing, and an exit aperture in the distal end of the housing. The body of the lumen gradually widens toward the distal end of the housing to accommodate the radial movement of surgical instruments under articulation control. 
         [0019]    The articulation structure is envisioned to have different configurations. In one configuration, the actuation member may be a worm gear, with the rotating members abutting the actuation member as gear wheels. In this configuration, the actuation member is restricted from linear translation along the longitudinal axis. 
         [0020]    In another configuration, the actuation structure is a toothed rack abutting rotating pinions. In this configuration, the actuation structure is free to translate along the longitudinal axis. 
         [0021]    Connecting the rotating members to the tubular members are rigid arms. The rigid arms are connected to the rotating members such that they rotate about an axis substantially transverse to the longitudinal axis when the actuation structure is engaged, i.e., they move radially with respect to a longitudinal axis of the device. This rotation of the rigid arms thus effects angular displacement of the tubular members, and any surgical instruments disposed therethrough, from the longitudinal axis. 
         [0022]    In some configurations, more than two tubular members, more than one actuation member, and/or more than two rotating members may be present, allowing for triangulation of multiple instruments with respect to multiple axes. In such configurations, actuation members may be oriented such that they articulate surgical instruments in multiple axes. Additionally, the spacing between tubular members may not be symmetrical about the longitudinal axis, so as to achieve a desired triangulation within a body member. 
         [0023]    A handle may extend proximally from the actuation member, through the housing and further proximally so that the handle may be engaged by an operator. This handle provides direct control of the articulation structure to the operator of the surgical access port. 
         [0024]    Also disclosed is a method for achieving triangulation, wherein the surgical access port is placed within a body member, surgical instruments are disposed in the surgical access port, and the actuating member is engaged such that articulation of the surgical instruments in a body cavity is achieved, allowing for triangulation of the instruments to determine the relative positioning of the end effectors of the surgical instruments. 
         [0025]    Further disclosed herein are the steps of performing a minimally invasive procedure through the surgical access port, removing the surgical instruments from the surgical access port, and removing the surgical access port from the body member following surgery. 
         [0026]    The various aspects of this disclosure will be more readily understood from the following detailed description when read in conjunction with the appended drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0027]    Embodiments of the present disclosure are described herein with reference to the accompanying drawings, wherein: 
           [0028]      FIG. 1  is a side perspective view of a surgical access port according to an embodiment of the present disclosure, disposed in an incision site (shown in cut-away view) and containing an articulation structure (shown in phantom view); 
           [0029]      FIG. 2  is a side view of the surgical access port, with a cylindrical member (shown in phantom view), and the articulation structure comprising two lumens, two tubular members, two rigid arms, and two gear wheels abutting a worm gear; 
           [0030]      FIG. 3  is a top plan view of the surgical access port shown in  FIG. 2 , with the articulation structure shown in phantom view. 
           [0031]      FIG. 3A  is a partial detail view of the area surrounding a lumen, tubular member, and rigid arm in  FIG. 3 ; 
           [0032]      FIG. 4  is a bottom plan view of the surgical access port shown in  FIG. 2 , with the articulation structure shown in phantom view and showing shaped lumen exits at the distal end of the cylindrical member; 
           [0033]      FIG. 5  is a side view of the surgical access port as shown in  FIG. 2 , disposed in a layer of tissue (shown in cut-away view) and with two surgical instruments inserted through the lumens; 
           [0034]      FIG. 6  is a side view of the surgical access port as shown in  FIG. 5 , with the articulation structure having been engaged and the tubular members and surgical instruments disposed at an angle with the longitudinal axis; 
           [0035]      FIG. 7  is a side view of an embodiment of a surgical access port (shown in phantom view), wherein more than two lumens and corresponding gear wheels and surgical instruments are present in an articulation structure; 
           [0036]      FIG. 8  is a side view of an embodiment of a surgical access port (shown in phantom view), wherein the articulation structure comprises a toothed rack abutting rotating pinions; and 
           [0037]      FIG. 9  is a side view of the surgical access port shown in  FIG. 8 , with the actuation structure having been engaged and the tubular members and surgical instruments disposed at an angle with the longitudinal axis. 
       
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS 
       [0038]    Embodiments of the presently disclosed surgical access ports for use in minimally invasive surgery are described in detail with reference to the drawings, in which like reference numerals designate identical or corresponding elements in each of the several views. As used herein, the term “distal” refers to that portion of the tool, or component thereof which is further from the user while the term “proximal” refers to that portion of the tool or component thereof which is closer to the user. The presently disclosed surgical access ports are usable in an incision through a patient&#39;s tissue or in a naturally occurring orifice (e.g. anus or vagina). 
         [0039]    Referring initially to  FIG. 1 , a surgical access port, generally designated as  100 , is shown. The surgical access port  100  is comprised of a cylindrical member  110  that has a generally hourglass profile. The cylindrical member  110  has a proximal end  110   a  and a distal end  110   b  and defines a longitudinal axis A 1 . Extending from the proximal end  110   a  to the distal end  110   b  of the cylindrical member  110  are two lumens  120 . Each lumen  120  has an entrance  120   a  in the proximal end  110   a  of the cylindrical member  110 , and an exit  120   b  in the distal end  110   b  of the cylindrical member  110 . The lumens  120  widen toward the distal end  110   b  of the cylindrical member  110  to accommodate radial movement within the surgical access port  100  of objects under articulation control. The lumen exits  120   b  are similarly elongated for this purpose. 
         [0040]    Disposed within the cylindrical member  110  is an articulation structure  130 , which comprises two tubular members  140  disposed in the lumens  120 , two worm wheels  160 , and a worm gear  150 . Extending proximally of the worm gear  150  and above the proximal end  110   a  of the cylindrical member  110  is a handle  180 . 
         [0041]    Turning now to  FIG. 2 , a side view of the surgical access port  100  is shown, with the cylindrical member  110  in phantom view and the articulation structure  130  shown in standard view. Looking to the articulation structure  130 , the worm gear  150  is configured to rotate about the longitudinal axis A 1 , but is restricted from axial translation along the longitudinal axis A 1 . The worm gear  150  abuts the worm wheels  160 , and helical thread  150   a  is configured to engage the teeth  160   a  of the worm wheels  160 . The worm wheels  160  are fixably attached to the rigid arms  170  by any suitable method, and may be integrally formed of the same member. The rigid arms  170 , in turn, are attached to the tubular members  140 . The attachment of the rigid arms  170  to the tubular members  140  is by way of an attachment to an outer surface of the tubular members  140 , and may be achieved by any suitable coupling method, such as adhesion or clamping. Extending proximally from the articulation structure  130  is a handle  180 . The handle  180  is operatively connected to the worm gear  150 , and is configured such that an operator of the surgical access port  100  may engage the articulation structure  130  by engaging the handle  180 . The handle  180  allows the operator of the surgical access port  100  to engage the articulation structure  130  from a point proximal of the cylindrical member  110 . 
         [0042]    Referring to  FIG. 3 , a top plan view of the surgical access port  100  is shown. The lumens  120  containing the tubular members  140  extend from a proximal end  110   a  of the cylindrical member  110 . At a distal end  110   b  ( FIG. 1 ) of the cylindrical member  110 , the exit aperture  120   b  of the lumens  120  can be seen in phantom view. The lumens  120  and exit aperture  120   b  of the lumens  120  widen towards the distal end  110   b  of the cylindrical member  110  such that the tubular members  140  and rigid arms  170  are allowed freedom of movement along an axis substantially transverse to the longitudinal axis A 1  ( FIG. 1 ). When the worm wheels  160  (shown in phantom) are set in motion by the worm gear  150 , they cause the rigid arms  170  and tubular members  140  to rotate, and the tubular members move radially through the widened lumen  120  and lumen exit aperture  120   b.    
         [0043]      FIG. 3A  shows an enlarged detail view of the area encompassing lumen  120 , tubular member  140 , and rigid arm  170  from the top plan view of  FIG. 3 . Tubular member  140  is shown disposed within the lumen  120 . Shown in phantom view is the widened lumen exit  120   b . Also shown in phantom view is the rigid arm  170  abutting the tubular member  140 . 
         [0044]    Turning now to  FIG. 4 , a bottom plan view of the surgical access port  100  is shown. In this view, the exit apertures  120   b  of the lumens  120  are shown in the foreground. As in  FIG. 3 , the rigid arms  170  are attached to the tubular members  140 . Upon engagement of the articulation member  150  ( FIG. 1 ), the tubular members  140  are displaced radially with respect to the longitudinal axis A 1  ( FIG. 1 ), and are allowed freedom of movement through the exit apertures  120   b  of the lumens  120 . Thus, the end effectors  195   b  ( FIG. 5 ) of the surgical instruments  195  ( FIG. 5 ) are placed at off-axis positions within an internal body cavity  190   b  ( FIG. 5 ). 
         [0045]    As seen in  FIG. 5 , the surgical access port  100  is configured to be disposed in a layer of tissue  190 , often at an incision site  190   a . The proximal and distal ends  110   a  and  110   b  of the cylindrical member  110  may include rims or flanges to aid in anchoring the surgical access port  100  in the layer of tissue  190 . Also shown is a pair of surgical instruments  195  having end effectors  195   b , disposed in the tubular members  140 . The surgical access port  100  is oriented such that the articulation structure  130  is substantially parallel to the longitudinal axis A 1  and the surgical instruments  195  and end effectors  195   b  are disposed in the tubular members  140  and exit within the internal body cavity  190   b.    
         [0046]    In use, the operator of the surgical access port  100  engages the handle  180  and actuates the worm gear  150 . Engagement of the handle  180  transmits torque to the worm gear  150 , causing it to rotate about the longitudinal axis A 1 . The helical thread  150   a  of the worm gear  150  engages the teeth  160   a  of the worm wheels  160 , and causes them to rotate about an axis substantially transverse to the longitudinal axis A 1 . The rotational motion of the worm wheels  160  in turn causes the rigid arms  170  to which they are attached to pivot about the axis of rotation of the worm wheels  160 . As the rigid arms  170  are attached to the tubular members  140  and the surgical instruments  195  and end effectors  195   b  are inserted therethrough, the pivoting of the rigid arms  170  causes radial displacement of the surgical instruments  195  and end effectors  195   b  with respect to the longitudinal axis A 1 . 
         [0047]    Turning now to  FIG. 6 , the surgical access port  100  is shown with the articulation structure  130  having been engaged. The worm wheels  160  have rotated in response to the rotation of the worm gear  150 . The pivoting of rigid arms  170  thus cause tubular members  140  and the surgical instruments  195  disposed therethrough to deflect with respect to the longitudinal axis A 1 . This displacement is permitted by the gradually widened lumens  120  toward the distal end  110   b  of the cylindrical member  110  and the lumen exit apertures  120   b . With worm gear  150  having been actuated a measured amount, and knowing the rate of rotation of the actuation structure  130 , the operator of the surgical access port  100  can determine the relative spacing of the end effectors  195   b  of the surgical instruments  195  with respect to a known point, such as the cylindrical member  110  or the longitudinal axis A 1 . 
         [0048]    Referring now to  FIG. 7 , another embodiment of a surgical access port, designated  200 , is shown. The articulation structure  230  of surgical access port  200  is configured to triangulate more than two surgical instruments  195 , and includes at least a third surgical instrument  295  with end effector  295   b . Disposed in the surgical access port  200  is a third lumen  220  containing a third tubular member  240 , and a corresponding third worm wheel  260  and third rigid arm  270 . The third worm wheel  260  is oriented on an axis substantially transverse to the longitudinal axis A 1 , but also different from the axis along which the first and second worm wheels  160  are disposed. The surgical access port  200  is configured such that upon actuation of the worm gear  150 , the third worm wheel  260  will rotate about an axis substantially transverse to the longitudinal axis A 1  (but different from the axes about which first and second worm wheels  160  rotate), and third tubular member  240  and third surgical instrument  295  will articulate in conjunction with the first two tubular members  140  and first two surgical instruments  195 . As explained above, the operator of the surgical access port  200  can determine the relative spacing of the end effectors  195   b ,  295   b  of the surgical instruments  195 ,  295  with respect to a known point, such as the cylindrical member  110  or the longitudinal axis A 1 . 
         [0049]    Turning now to  FIG. 8 , a surgical access port  300  is shown, which contains a toothed rack  350  as an actuation member. The toothed rack  350  is attached to a handle  180  extending proximally from the cylindrical member  110 . In use, the handle  180  is engaged by an operator at the proximal end  110   a  of the cylindrical member  110 , force is transmitted to the toothed rack  350 . The toothed rack  350  translates along the longitudinal axis A 1 . As the toothed rack  350  moves distally along the longitudinal axis A 1 , the teeth  350   a  of the toothed rack engage the teeth  360   a  of pinions  360  and cause them to rotate about an axis substantially transverse to the longitudinal axis A 1 . The rigid arms  170 , attached to the pinions  360 , pivot about the axis about which the rotating members rotate, and cause the tubular members  140  to which they are connected to displace radially from the longitudinal axis A 1 . 
         [0050]    Referring to  FIG. 9 , the surgical access port  300  is shown in an actuated state, with the toothed rack  350  displaced distally along the longitudinal axis A 1 . The pinions  360 , rigid arms  170 , and tubular members  140  have all pivoted about axes transverse to the longitudinal axis A 1 , resulting in the surgical instruments  195  disposed therethrough to be displaced radially to a desired position within the internal body cavity  190   b . As in the previous embodiments, the known dimensions of the articulation structure  330  allows an operator of the surgical access port  300  to determine the relative spacing of the end effectors  195   b  of the surgical instruments  195  with respect to a known point, such as the cylindrical member  110  or the longitudinal axis A 1 . 
         [0051]    It will be understood that various modifications may be made to the embodiments of the presently disclosed surgical access ports. Therefore, the above description should not be construed as limiting, but merely as exemplifications of embodiments. Those skilled in the art will envision other modifications within the scope and spirit of the present disclosure.