Patent Publication Number: US-2021177244-A1

Title: Devices, systems, and methods for minimally invasive surgery in a body lumen

Description:
CROSS REFERENCE TO RELATED 
     The present application is a non-provisional of, and claims the benefit of priority under 35 U.S.C. § 119 to, U.S. Provisional Application Ser. No. 62/947,659, filed Dec. 13, 2019, the disclosures of which are herein incorporated herein by reference in their entirety. 
    
    
     FIELD 
     The present disclosure relates generally to the field of medical devices for operatively treating gastrointestinal disorders endoscopically in a stable, yet dynamic operative environment, and in a minimally invasive manner. In particular, the present disclosure relates to medical devices, systems and methods for expanding a body lumen to provide a customizable working space for maneuverability of endoscopic instruments. 
     BACKGROUND 
     Endoscopic procedures involving the gastrointestinal system can be less invasive than traditional procedures and may enable expansion of a stable, working space adjacent to the target tissues that could otherwise collapse around the target lesion or defect during an operative treatment. A better expanded, stable and optimally configured working space enables instruments and endoscope to be independently manipulated and visualized around the target tissue. 
     It is with the above considerations in mind that the improvements of the present disclosure may be useful. 
     SUMMARY 
     The present disclosure, in its various aspects, relates to tissue devices and methods for providing a working space within a body lumen. 
     A system is disclosed for performing minimally invasive procedures in a body lumen of a patient. The system may include a flexible tubular member having a first lumen for receiving an endoscope, and an adjustable cage disposed at a distal end of the flexible tubular member. The adjustable cage can include a plurality of flexible elements that are independently and selectively movable laterally outwardly to move a side wall of the body lumen outwardly to increase visualization and a working space within the body lumen. The system may include a handle having a plurality of actuators movably disposed with respect to a body portion of the handle, where each of the plurality of actuators is coupled to a selected one of the plurality of flexible elements such that moving one of the plurality of actuators extends or retracts the coupled flexible element to adjust the shape of the adjustable cage. 
     In some embodiments, the plurality of flexible elements are fixedly coupled between the plurality of actuators and a cap member disposed at a distal end of the system. In some embodiments, the plurality of flexible elements comprise first, second, third and fourth flexible elements. In some embodiments, the plurality of flexible elements comprise wires. In some embodiments, the adjustable cage forms a working space therein. The system may further include a cap member coupled to distal ends of the plurality of flexible elements. 
     In some embodiments, a shape of the adjustable cage is selectively adjustable by actuating one or more of the plurality of actuators to orient the cap member toward a targeted lesion. In some embodiments, the cap member comprises an opening sized and configured to receive an endoscope therethrough. In some embodiments, the cap member comprises one or more slits radiating from the opening. In some embodiments, the cap member comprises a lateral slit between proximal and distal ends of the cap member for allowing the endoscope to laterally disengage from the cap member through the lateral slit. 
     The system may further include a connecting member disposed between a distal end of the flexible tubular member and a proximal end of the cap member, the connecting member including a flexible braid element. The system may further include first and second working channels coupled between first and second lumens of the flexible tubular member and the cap member. In some embodiments, the adjustable cage has a retracted configuration and an extended configuration, and a length of the adjustable cage in the retracted configuration is smaller than the length of the adjustable cage in the extended configuration. In some embodiments, the adjustable cage has a contracted configuration and an expanded configuration, and an outer dimension of the adjustable cage in the contracted configuration is smaller than the outer dimension of the adjustable cage in the expanded configuration. In some embodiments, the flexible tubular member comprises a multilayer construction having layers selected from the list consisting of a polymer layer, a braid layer, and a helical coil layer. 
     A system is disclosed for performing minimally invasive procedures in a body lumen of a patient. The system can include a flexible tubular member having a first lumen for receiving an endoscope, and an adjustable cage disposed at a distal end of the flexible tubular member. The adjustable cage can include a plurality of flexible elements that are independently and selectively movable laterally outwardly to move a side wall of the body lumen outwardly to increase visualization and a working space within the body lumen. The system can include a handle having a plurality of actuators movably disposed with respect to a body portion of the handle, each of the plurality of actuators coupled to a selected one of the plurality of flexible elements such that moving one of the plurality of actuators extends or retracts the coupled flexible element to adjust the shape of the adjustable cage. 
     In some embodiments, the plurality of flexible elements are fixedly coupled between the plurality of actuators and a cap member disposed at a distal end of the system. In some embodiments, the plurality of flexible elements comprise first, second, third and fourth flexible elements. In some embodiments, the plurality of flexible elements comprise wires. In some embodiments, the adjustable cage forms a working space therein. 
     The system may further include a cap member coupled to distal ends of the plurality of flexible elements. In some embodiments, a shape of the adjustable cage is selectively adjustable by actuating one or more of the plurality of actuators to orient the cap member toward a targeted lesion. In some embodiments, the cap member comprises an opening sized and configured to receive an endoscope therethrough. In some embodiments, the cap member comprises one or more slits radiating from the opening. 
     In some embodiments, the cap member comprises a lateral slit between proximal and distal ends of the cap member for allowing the endoscope to laterally disengage from the cap member through the lateral slit. The system may further include a connecting member disposed between a distal end of the flexible tubular member and a proximal end of the cap member, the connecting member including a flexible braid element. The system may further include first and second working channels coupled between first and second lumens of the flexible tubular member and the cap member. 
     In some embodiments, the adjustable cage has a retracted configuration and an extended configuration, and a length of the adjustable cage in the retracted configuration is smaller than the length of the adjustable cage in the extended configuration. In some embodiments, the adjustable cage has a contracted configuration and an expanded configuration, and an outer dimension of the adjustable cage in the contracted configuration is smaller than the outer dimension of the adjustable cage in the expanded configuration. 
     In some embodiments, the flexible tubular member comprises a multilayer construction having layers selected from the list consisting of a polymer layer, a braid layer, and a helical coil layer. In some embodiments, the plurality of flexible elements are disposed through openings in a distal end of the flexible tubular member. In some embodiments, the openings have axes, each of said axes being oriented at an oblique angle with respect to a longitudinal axis of the flexible tubular member. 
     A method is disclosed for performing a minimally invasive procedure in a body lumen of a patient. The method can include: inserting a flexible tubular member into a body lumen and navigating an adjustable cage of the flexible tubular member toward a targeted lesion, the adjustable cage comprising a plurality of flexible element; manipulating at least one actuator of a plurality of actuators to extend or retract one of a plurality of flexible elements of the adjustable cage to selectively adjust a shape of the adjustable cage dependent upon a position of the targeted lesion, wherein each one of the plurality of actuators is individually associated with one of the plurality of flexible elements; and inserting a working instrument through the flexible tubular member to perform an operation on a lesion adjacent to the adjustable cage. 
     The method may further include inserting an endoscope through the flexible tubular member and extending the endoscope through an opening in a cap member of the adjustable cage to visualize a portion of the body lumen beyond a distal end of the adjustable cage. The method may further include performing an operation on a lesion to comprises performing an operation on a lesion disposed distal to the cap member. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Non-limiting embodiments of the present disclosure are described by way of examples with reference to the accompanying figures, which are schematic and not intended to be drawn to scale. In the figures, each identical or nearly identical component illustrated is typically represented by a single numeral. For purposes of clarity, not every component is labeled in every figure, nor is every component of each embodiment shown where illustration is not necessary to allow those of ordinary skill in the art to understand the disclosure. In the figures: 
         FIG. 1  illustrates a minimally invasive surgical system according to an embodiment of the present disclosure. 
         FIG. 2  is a cross-section view of a portion of the system of  FIG. 1 , taken alone line  2 - 2  of  FIG. 1 . 
         FIG. 3  is an isometric view of an adjustable cage of the system of  FIG. 1 , the adjustable cage being in an expanded configuration. 
         FIG. 4  is a side view of the adjustable cage of the system of  FIG. 1 , the adjustable cage being an unexpanded, delivery, configuration. 
         FIG. 5  is a top view of the adjustable cage of the system of  FIG. 1 , the adjustable cage being an unexpanded, delivery, configuration. 
         FIG. 6  is a side view of a handle portion of the system of  FIG. 1 . 
         FIG. 7  is a cross-section view of the handle portion of  FIG. 6 , taken alone line  7 - 7  of  FIG. 6 . 
         FIG. 8  is another cross-section view of the handle portion of  FIG. 6 , taken alone line  8 - 8  of  FIG. 6 . 
         FIG. 9  is a cross-section view of a cap portion of the system of  FIG. 1 , taken alone line  9 - 9  of  FIG. 5 . 
         FIG. 10  is a cross-section view of the flexible tubular member of the system of  FIG. 1 , taken alone line  9 - 9  of  FIG. 6 . 
         FIG. 11  is an isometric view of the handle portion of the system of  FIG. 1 , shown in the context of example instrument guides. 
         FIG. 12-14  are side views of example hockey stick and cobra instrument guides and a tissue manipulator for use with the system of  FIG. 1 . 
         FIGS. 15 and 16  are side views of example instrument guide and tissue manipulator handles for use with the instrument guides and manipulator of  FIGS. 12-14 . 
         FIGS. 17-24  illustrate various positionings of the system of  FIG. 1  to approach lesions in different locations with an example body lumen. 
         FIG. 25  is a top view of an adjustable cage of the system of  FIG. 1  according to the present disclosure. 
         FIG. 26  is a side view of the adjustable cage of  FIG. 25   
         FIG. 27  is an isometric view of the adjustable cage of  FIG. 25 . 
         FIG. 28  is a further isometric view of the adjustable cage of  FIG. 25  with an endoscope in an extended position. 
         FIG. 29  is a side view of the adjustable cage of  FIG. 25  with an endoscope and an instrument guide in extended positions with respect to the adjustable cage. 
         FIG. 30  is a top view of the adjustable cage of  FIG. 25  with a cap of the adjustable cage in a laterally angled position. 
         FIG. 31  is a side view of the adjustable cage of  FIG. 25  with the cap of the adjustable cage in an alternate laterally angled position. 
         FIG. 32  is a side view of the adjustable cage of  FIG. 25  with the cap of the adjustable cage in a further alternate laterally angled position. 
         FIG. 33  is a side view of the adjustable cage of  FIG. 25  with an endoscope and an instrument guide in extended positions with respect to the adjustable cage. 
     
    
    
     DETAILED DESCRIPTION 
     The present disclosure is not limited to the particular embodiments described. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting beyond the scope of the appended claims. Unless otherwise defined, all technical terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the disclosure belongs. 
     Although embodiments of the present disclosure may be described with specific reference to medical devices and systems, it should be appreciated that such medical devices and systems may be used in a variety of medical procedures that require grasping, retracting, and resecting tissue in GI tract. The disclosed medical devices and systems may also be inserted via different access points and approaches, e.g., percutaneously, endoscopically, laparoscopically, or combinations thereof. 
     As used herein, the singular forms “a,” “an,” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms “comprises” and/or “comprising,” or “includes” and/or “including” when used herein, specify the presence of stated features, regions, steps, elements and/or components, but do not preclude the presence or addition of one or more other features, regions, integers, steps, operations, elements, components and/or groups thereof. 
     As used herein, “proximal end” refers to the end of a device that lies closest to the medical professional along the device when introducing the device into a patient, and “distal end” refers to the end of a device or object that lies furthest from the medical professional along the device during implantation, positioning, or delivery. 
     As used herein, the conjunction “and” includes each of the structures, components, features, or the like, which are so conjoined, unless the context clearly indicates otherwise, and the conjunction “or” includes one or the others of the structures, components, features, or the like, which are so conjoined, singly and in any combination and number, unless the context clearly indicates otherwise. 
     All numeric values are herein assumed to be modified by the term “about,” whether or not explicitly indicated. The term “about,” in the context of numeric values, generally refers to a range of numbers that one of skill in the art would consider equivalent to the recited value (e.g., having the same function or result). In many instances, the term “about” may include numbers that are rounded to the nearest significant figure. Other uses of the term “about” (e.g., in a context other than numeric values) may be assumed to have their ordinary and customary definition(s), as understood from and consistent with the context of the specification, unless otherwise specified. The recitation of numerical ranges by endpoints includes all numbers within that range, including the endpoints (e.g.  1  to  5  includes 1, 1.5, 2, 2.75, 3, 3.80, 4, and 5). 
     It is noted that references in the specification to “an embodiment,” “some embodiments,” “other embodiments,” etc., indicate that the embodiment(s) described may include a particular feature, structure, or characteristic, but every embodiment may not necessarily include the particular feature, structure, or characteristic. Moreover, such phrases are not necessarily referring to the same embodiment. Further, when a particular feature, structure, or characteristic is described in connection with an embodiment, it would be within the knowledge of one skilled in the art to affect such feature, structure, or characteristic in connection with other embodiments, whether or not explicitly described, unless clearly stated to the contrary. That is, the various individual elements described below, even if not explicitly shown in a particular combination, are nevertheless contemplated as being combinable or arrangeable with each other to form other additional embodiments or to complement and/or enrich the described embodiment(s), as would be understood by one of ordinary skill in the art. 
       FIGS. 1 and 2  illustrate an embodiment of a system  10  for performing minimally invasive surgery in a body lumen. The system  10  may include a flexible tubular member  11  having a proximal end  13  including a handle  24 , and a distal portion  38  including an adjustable cage  40  for positioning within the body lumen adjacent a targeted lesion. 
     The flexible tubular member  11  may be configured to receive one or more instruments therethrough, and in some embodiments the flexible tubular member  11  can have multiple lumens  12 ,  14  to receive such instruments. The flexible tubular member  11  can also include a lumen  28  configured and dimensioned to receive an endoscope  30 , which may be an articulating endoscope (including but not limited to an endoscope, bronchoscope, colonoscope, catheter delivery system, and the like), as well as first and second lumens  12 ,  14 , which in some non-limiting example embodiments comprise fluoropolymer (Teflon) tubing. As will be appreciated, any number of lumens can be provided within the flexible tubular member  11 , at any position, to provide the user with flexibility in determining a desired instrument insertion position based on the position of the lesion within the body lumen. 
     As mentioned, flexible tubular member  11  includes a handle  24  at the proximal portion  13 . As will be described, the handle  24  may have multiple actuation elements to enable a user to selectively adjust a size, shape and/or position of the adjustable cage  40 . Flexible tubular member  11  can also include tubing  26  which may be an insufflation port for supplementing insufflation gas provided by the endoscope  30 . 
     Adjustable cage  40  is shown in a collapsed configuration in  FIG. 1 . As will be appreciated, the adjustable cage  40  may be positioned in the collapsed configuration when the flexible tubular member  11  is inserted into the body lumen. Once the adjustable cage  40  is navigated through the body lumen and positioned adjacent to a targeted lesion, the user may selectively expand the adjustable cage into an expanded configuration. In some embodiments the expansion of the adjustable cage can be selectively asymmetric to maximize space for a tool and an endoscope to visualize a target tissue and treat the target tissue from outside the patient in a minimally invasive manner. When expanded, the adjustable cage  40  outwardly engages one or more walls of the body lumen to expand the body lumen, providing an increased working space to enable tools extended through the flexible tubular member  11  to access a lesion within the body lumen. As will be appreciated, providing an increased working space enables the instruments inserted into the space to have a wider range of motion for engaging a lesion than would otherwise be available in the absence of such expansion. 
     The flexible tubular member  11  may be sufficiently flexible, and of sufficiently small girth, to navigate through long, tortuous paths associated with body lumens so that lesions disposed in far reaches of the body lumens can be reached and removed using the system  10 . As can be appreciated, the flexures required to traverse such lengths of body lumens can cause the distal portion  38  of the flexible tubular member  11  to bias to an outer section of the lumen when the distal portion encounters a particular curvature of the lumen. This can make it difficult to move the flexible tubular member  11  past such curvatures to reach a targeted lesion. Such long tortuous paths can also result in kinking or binding of moving components and mechanisms associated with the flexible tubular member  11 , which can inhibit some or all the functionality of the system  10 . As will be described, the system  10  according to disclosure includes features to facilitate movement of the flexible tubular member  11  around such curvatures. 
     In addition to enabling the flexible tubular member  11  to navigate the body lumen, it is often desirable to apply torque to the flexible tubular member  11  to rotate the distal portion  38  to obtain a desired alignment of the adjustable cage  40  and/or the endoscope  30  or the instruments. Such rotational positioning enables tasks such as visualization, retraction, space creation, and/or resection to be achieved. As will be appreciated, transmitting torque along the entire length of a flexible tubular member can be difficult in a long device that has multiple bends along its length. As will also be described, the system  10  according to the disclosure includes features that enhance the torque-transmission capacity of the flexible tubular member  11 . 
     Referring now to  FIGS. 3-5 , an adjustable cage  40  may comprise a plurality of flexible elements  42 ,  44 ,  46 ,  48 , that can be independently adjustable to enable a user to selectively adjust a size and shape of the adjustable cage. In the illustrated embodiment, the plurality of members  42 ,  44 ,  46 ,  48  comprise a plurality of wires that form a cage. It will be appreciated that although the illustrated embodiment includes four flexible elements, greater or fewer flexible elements can be employed to form the adjustable cage  40 . In addition, although the illustrated embodiment shows the flexible elements as being wires, the flexible elements can be made from any structural elements that can provide the desired functionality as will be described herein. 
     As shown, the plurality of flexible elements  42 ,  44 ,  46 ,  48  each have a distal end  42   a ,  44   a ,  46   a ,  48   a  that is fixedly coupled to a cap member  50 . Proximal ends  42   b ,  44   b ,  46   b ,  48   b  ( 44   b  only shown in  FIG. 7 ) of the plurality of flexible elements  42 ,  44 ,  46 ,  48  are coupled to respective actuators  52 ,  54 ,  56 ,  58  ( FIG. 6 ) associated with handle  24 . As will be described, the flexible elements  42 ,  44 ,  46 ,  48  can be disposed within the flexible tubular member  11  and exit through openings  60 ,  62 ,  64 ,  66  adjacent a distal end  68  of the flexible tubular member  11  ( FIG. 3 ). The plurality of flexible elements  42 ,  44 ,  46 ,  48  can be independently extended and retracted with respect to the distal end  68  of the flexible tubular member  11  by individually actuating the respective actuators  52 ,  54 ,  56 ,  58  of the handle  24 . In this manner, the shape of the adjustable cage  40  can be customized in order to obtain a working space  70  that is shaped so that instruments inserted into the working space can access a targeted lesion. 
       FIG. 3  shows the adjustable cage  40  in an expanded configuration. In the illustrated configuration two of the flexible elements  42 ,  44  are extended while the other two flexible elements  46 ,  48  are either maintained in place or retracted. This results in the adjustable cage being bowed on one side to provide a desired asymmetrical expansion of the body lumen on that side of the adjustable cage  40 . Since the plurality of flexible elements  42 ,  44 ,  46 ,  48  are independently extendable/retractable, the adjustable cage  40  is infinitely adjustable by the user to obtain a working space  70  that has a desired shaped, depending on the shape of the body lumen and the position of the targeted lesion. This provides the user with an enhanced array of options for accessing a lesion using one or more instruments and an endoscope disposed through the flexible tubular member  11 . 
     As can be seen in  FIG. 3 , endoscope  30  is extendible through lumen  28  into working space  70  formed by the adjustable cage  40 . Also extendable into the working space  70  are a first instrument  72  which can extend from a working channel  74  in the endoscope  30 , a second instrument  77  which can extend from the first lumen  12  ( FIG. 2 ) in the flexible tubular member  11 , and a third instrument  79  which can extend from the second lumen  14  ( FIG. 2 ) in the flexible tubular member  11 . As will be appreciated, the disclosed arrangement can enable a variety of visualization and tissue manipulation functions to be performed on a targeted lesion. 
     In some non-limiting example embodiments, the plurality of flexible elements  42 ,  44 ,  46 ,  48  are wires made from nickel titanium (e.g., super-elastic or shape memory metal such as Nitinol) that are rigidly coupled at distal ends  42   a ,  44   a ,  46   a ,  48   a  to the cap member  50 . In non-limiting example embodiments, the wires have diameters from 0.010-0.080 inches. The cap member  50  may be made from any appropriate material, a non-limiting example listing of which includes polycarbonate, ABS, PeBax, polyamide, and polyethylene rigid plastic. The cap member  50  may also include an opening  71  sized to allow a tip of the endoscope to nest therein, for example, while the system  10  is being navigated through the body lumen. The opening  71  may also allow a portion of the endoscope  30  to pass therethrough to facilitate visualization of the body lumen and/or the targeted lesion using a visualization capability of the endoscope. 
     A cap member  75  may be disposed on or over the distal end  68  of the flexible tubular member  11 . As shown in  FIG. 9 , the plurality of flexible elements  42 ,  44 ,  46 ,  48  are received through respective openings  76 ,  78 ,  80 ,  82  in the cap member  75 . The cap member  75  can also include an opening  84  aligned with a portion of the lumen  28  in the flexible tubular member  11  for receiving the endoscope  30  therethrough, and respective openings  86 ,  88  aligned with the first and second lumens  12 ,  14  in the flexible tubular member  11  through which instruments and/or tool guides can extend. The cap member  75  can also include a window opening  77  (see  FIGS. 4 and 5 ) lateral to the lumen opening  84  ( FIG. 9 ) of the cap member  75  to facilitate lateral egress of the endoscope  30  from the flexible tubular member  11 . 
     Referring now to  FIGS. 6-8 , the handle  24  may be coupled to a proximal end  90  of the flexible tubular member  11 . As mentioned, the handle  24  can include a plurality of actuators  52 ,  54 ,  56 ,  58 , each of which may be coupled, directly or indirectly, to one of the plurality of flexible elements  42 ,  44 ,  46 ,  48 . In the illustrated embodiment the plurality of actuators  52 ,  54 ,  56 ,  58  are slidably coupled to the handle  24  so that they can be selectively moved in directions parallel to the longitudinal axis A-A of the system  10 . As will be described in greater detail, coupling each of the plurality of actuators  52 ,  54 ,  56 ,  58  to a single one of the plurality of flexible elements  42 ,  44 ,  46 ,  48  enables a user to selectively actuate one or more of actuators (e.g., sliding them toward or away from the adjustable cage  40 ) to independently move the flexible elements  42 ,  44 ,  46 ,  48  to adjust the size and/or shape of the adjustable cage  40 . In some non-limiting example embodiments, two or more of the actuators  52 ,  54 ,  56 ,  58  could be coupled together to operate multiple wires simultaneously, if desired. 
     As shown in greater detail in  FIG. 7 , actuator  54  is operably connected to a flexible element (e.g., flexible element  44 ) via an element coupler  92 . It will be appreciated that although this description will progress in relation to actuator  54 , the same description will apply to the other actuators  52 ,  56 ,  58  associated with the handle  24 . The actuator  54  can be reversibly engageable with the handle  24  such that the actuator  54  can be reversibly fixed in position relative to the handle  24 . In some embodiments, the actuator  54  can be multi-positional, having a plurality of positions for extension and retraction of an associated flexible element (e.g., flexible element  44 ). In one non-limiting example embodiment, the actuator  54  can have a plurality of ratchet teeth  94  for engaging corresponding ratchet teeth  96  of the handle  24 , to provide a plurality of positions for reversibly fixing the retractor in position during expansion or collapse of the retractor. The actuator  54  may be selectively locked with a spring-loaded plunger (not shown) which biases the ratchet teeth  94  of the actuator  54  into engagement with the ratchet teeth  96  of the handle  24  to hold the actuator  54  (and the associated flexible element  44 ) in a desired position. The user can push on the actuator to release the lock and slide the actuator  54  in either direction (i.e., toward or away from the adjustable cage  40  along axis A-A) to extend or retract the flexible element  44 . 
     The handle  24  can be provided in any of a variety of shapes to achieve a desired ergonomic configuration for operation of the system by way of example, the actuator  54  can be configured as a finger-activated actuator on the handle  24  that slides back and forth through a slot  98  ( FIG. 6 ) in the handle  24  to expand or collapse the retractor elements. An arrangement for dynamically adjusting or ratcheting the retractor position can be provided along the slot  98  to lock the position of the flexible elements in place when the associated actuator is not pressed. 
     As discussed, by enabling the individual flexible elements  42 ,  44 ,  46 ,  48  to be extended, retracted, or held in place via selective activation of one or more of the actuators  52 ,  54 ,  56 ,  58 , the adjustable cage  40  can be lengthened (i.e., extended), shortened (i.e., retracted), and/or adjusted to achieve a variety of laterally expanded and contracted configurations. For example, the expansion of the adjustable cage can be selectively asymmetric to maximize space for a tool and an endoscope to visualize a target tissue and treat the target tissue from outside the patient in a minimally invasive manner. 
     Thus, in some embodiments the actuators  52 ,  54 ,  56 ,  58  can be moved between an extended position in which the adjustable cage  40  has a first length, and a retracted position in which the adjustable cage  40  has a second length smaller than the first length. In one non-limiting example embodiment the first length is from 5 cm to 15 cm, while the second length is from 4 cm to 0 cm. In some embodiments the user may configure the adjustable cage in the retracted and unexpanded configuration during navigation through the body lumen. Once the adjustable cage has been navigated through the body lumen and positioned adjacent to a targeted lesion, one or more of the actuators  52 ,  54 ,  56 ,  58  can be adjusted to configure the adjustable cage  40  in the extended and expanded configuration to provide access to the lesion by the endoscope  30  and one or more instruments. 
     In some embodiments, some or all of the flexible elements  42 ,  44 ,  46 ,  48  may be provided with a pre-determined curvature so that the resulting adjustable cage  40  is biased into a desired pre-determined shape. In some embodiments, the openings  76 ,  78 ,  80 ,  82  in the cap member  75  may have a desired orientation (e.g., they may be oriented at an oblique angle (e.g., up to and including 45-degrees) with respect to the longitudinal axis A-A of the system  10  so that the curvatures of the individual flexible elements  42 ,  44 ,  46 ,  48  are aligned with the trajectory of the openings, positioning the convexity of the flexible elements on the outside of the adjustable cage  40 . In some embodiments, one or more openings  76 ,  78 ,  80 ,  82  in the cap member  75  may be oriented at oblique angles of from 1-45°, or from 5-30°, with respect to the longitudinal axis A-A of the system  10 . In such embodiments, the adjustable cage  40  may form an overall convex “football” shape when the flexible elements  42 ,  44 ,  46 ,  48  are extended. In some example embodiments, rigid guide tubes may be embedded in the cap member  75  to provide a desired orientation to the flexible elements  42 ,  44 ,  46 ,  48 . In some embodiments, convexity can be facilitated by pre-stressing and/or pre-shaping one or more of the flexible elements  42 ,  44 ,  46 ,  48 . In other embodiments, convexity is implemented by extending one or more of the flexible elements  42 ,  44 ,  46 ,  48  while maintaining or shortening the length of other of the flexible elements to force the extended flexible elements into a bow shape. 
     During insertion of the system  10  into the body lumen, and while navigating the adjustable cage  40  to a target lesion, the actuators  52 ,  54 ,  56 ,  58  on the handle  24  can be moved within their respective slots  98  ( FIG. 6 ) in a direction away from the adjustable cage  40 . This can cause the associated flexible elements  42 ,  44 ,  46 ,  48  to retract, thereby shortening the adjustable cage  40  to assume the shortened, second length to facilitate advancement of the adjustable cage  40  around curves of the body lumen. 
     With the adjustable cage  40  configured to assume the shortened, second length, the adjustable cage  40  will have increased torsional stiffness (as compared to its torsional stiffness in the extended configuration), and can be more easily rotated to align the system  10  in a desired orientation with minimal twisting along the length of the flexible tubular member  11 . In addition, during navigation through the body lumen, one or more of the flexible elements  42 ,  44 ,  46 ,  48  can be extended to provide the adjustable cage  40  with a curvature that matches a particular curvature of the lumen. This steerability, achieved through selective movement of individual actuators  52 ,  54 ,  56 ,  58  makes traversing such curves easier. 
     Once the adjustable cage  40  has been navigated within the body lumen to a desired position with respect to the targeted lesion, the actuators  52 ,  54 ,  56 ,  58  can be moved within their respective slots  98  to extend the length of the adjustable cage  40  to span the lesion so that a desired working space  70  can be achieved. 
     As mentioned, the flexible tubular member  11  may have enhanced torsional stiffness, which can enable the flexible tubular member to be easily rotated to align the system  10  in a desired orientation, with minimal twisting along the length of the flexible tubular member.  FIG. 10  illustrates an exemplary construction of the flexible tubular member  11 . 
     In general, the flexible tubular member  11  comprises a multi-layer construction including one or more polymer layers and one or more reinforcing layers. In the illustrated embodiment, a first braid layer  102  is surrounded by a metal helical coil layer  104 . The metal helical coil layer  104  is surrounded by a first polymer tubing layer  106 . The first polymer tubing layer  106  is surrounded by a second braid layer  107 . The second braid layer  107  is surrounded by a second polymer tubing layer  108 , and a third polymer tubing layer  110  overlies the second polymer tubing layer  108 . 
     The layers are assembled and subjected to heat sufficient to melt the first, second and third polymer tubing layers  106 ,  108 ,  110 , such that they melt through the metal helical coil layer  104  and the first and second braid layers  102 ,  107 , bonding the layers together and acting as a flexible matrix that holds the layers together. 
     The first braid layer  102 , first polymer tubing layer  106 , second braid layer  107  and second polymer tubing layer  108  may all be of the same length “L 1 ”, which in non-limiting example embodiments is 28-40 inches. The metal helical coil layer  104  may be of shorter length “L 2 ”, which in one non-limiting example embodiment is 18-30 inches. The third polymer tubing layer  110  may be of yet a shorter length “L 3 ”, which in non-limiting example embodiment is 11-23 inches. The outer diameter “OD” of the flexible tubular member  11  may, in non-limiting example embodiments, be 1.120 inches to 0.620 inches. The inner diameter “ID” of the flexible tubular member  11  may, in non-limiting example embodiments, be 0.900 inches to 0.500 inches. 
     The first, second and third polymer tubing layers  106 ,  108 ,  110  may be an elastomeric material such as Polyvinyl Chloride (PVC) or polyurethane, with a durometer of from 25-65 Shore A. The first, second and third polymer tubing layers may each have thickness of 0.25-0.05 inches before lamination. 
     The metal helical coil layer  104  can be made of a metal such as stainless steel, titanium alloy or cobalt chromium and can be 0.005-0.020 inches thick. 
     The first and second braid layers  102 ,  107  may be made of a material such as Polyether ether Ketone (PEEK), steel alloy, or Nickel Titanium alloy, having a higher stiffness than the polymer tubing, and having a high yield strain (e.g., 4-10%). 
     As will be appreciated, providing multiple layers of braid embedded in an elastomeric matrix throughout the length of the flexible tubular member  11  can result in a flexible tubular member  11  that is resilient and sufficiently stiff and strong in the radial direction to resist collapse of the lumens, which must accommodate instruments and the endoscope  30 . The resulting flexible tubular member  11  is also sufficiently flexible to bend and navigate through the tortuous path of a body lumen, while being sufficiently torsionally rigid that it can accommodate torque transmission, to thereby allow a user to torque the handle to rotate the adjustable cage  40  and orient the endoscope  30  and instruments to desired positions for accessing a lesion. 
     In some embodiments, the distal end  68  of the flexible tubular member  11  may couple to the cap member  75  adjacent to the adjustable cage  40 , while the proximal end  90  of the flexible tubular member  11  may attach to the handle  24 . The distal end  101  will have less torsional rigidity than the proximal end  103 . Since the proximal end  103  of the flexible tubular member  11  does not have to be as flexible as the remainder of the flexible tubular member, additional reinforcement using a metal coil and thicker polymer matrix is provided to further increase torsional and radial stiffness/strength near the handle. 
     As shown in  FIGS. 6-8 , the proximal end  90  of the flexible tubular member  11  is coupled to the handle  24 . The handle  24  includes four actuators  52 ,  54 ,  56 ,  58 , each of which is coupled to a respective one of the plurality of flexible elements  42 ,  44 ,  46 ,  48 . Each of the plurality of actuators  52 ,  54 ,  56 ,  58  can be slid back (i.e., away from the adjustable cage  40 ) to shorten the associated flexible element  42 ,  44 ,  46 ,  48  and place that member in tension, or can be slid forward (i.e., toward the adjustable cage  40 ) to lengthen the associated flexible element. As previously mentioned, the actuator  52 ,  54 ,  56 ,  58  can be locked in a desired position via interaction of a spring-loaded plunger and associated ratchet teeth associated with the handle  24 . The user can release the lock by pressing the plunger and can slide the actuator in either direction (i.e., toward or away from the adjustable cage). 
     The flexible elements  42 ,  44 ,  46 ,  48  can be made from material having a stiffness and strength similar to metals such as Nickel Titanium, Cobalt Chromium or Stainless Steel. In some embodiments, the flexible elements  42 ,  44 ,  46 ,  48  can be constrained within respective braided tubes (e.g., metal braid in polyimide having a thickness of between 0.003-0.010″) within the flexible tubular member  11 . The braided tubes can each have an inner diameter 0.001-0.008 inches larger than the diameter of the associated flexible element  42 ,  44 ,  46 ,  48  to allow flexible elements to slide axially (i.e., along the longitudinal axis A-A of the system  10 ). The braided tubes may be attached to proximal and distal ends  90 ,  68  of the flexible tubular member  11  to maintain the flexible elements  42 ,  44 ,  46 ,  48  aligned and located about the circumference of the flexible tubular member. In some embodiments, the braided tubes are free floating inside the flexible tubular member  11  to enable the flexible tubular member to easily flex to navigate through tortuosity. In some embodiments, the braided tubes may be adhered to an inner surface of the flexible tubular member  11 . In other embodiments, the braided tubes may be allowed to “float” within the flexible tubular member  11 . 
     As shown in  FIG. 11 , the handle  24  may include one or more ports  112  with associated sealing valves  114  disposed at a proximal end  116  of the handle to allow for insertion of one or more instruments guides (and/or instruments)  118  and an endoscope  30 . The lumens  12 ,  14 ,  28  may be in communication with such ports  112  so that the instrument guides  118 ,  128  and endoscope can be inserted through the proximal end  116  of the handle  24  and extended through the flexible tubular member  11  to access the working space  70  associated with the adjustable cage  40  ( FIG. 2 ). Tubing (not shown) can be coupled to the ports  112  and can be disposed within the handle  24  to couple the ports  112  to the lumens  12 ,  14 ,  28  of the flexible tubular member  11 . In some embodiments the tubing can be a flexible polymer such as fluoropolymer (Teflon) to guide the passage of instruments guides (and/or instruments) and the endoscope  30 . As previously noted, the first and second lumens  12 ,  14  may likewise be made from fluoropolymer (Teflon) and may be allowed float freely inside the lumen  28  of the flexible tubular member  11  to enable the flexible tubular member to maintain a desired flexibility. The endoscope  30  may reside within the portion of the lumen  28  not taken up by the first and second lumens  12 ,  14 . Thus, the effective lumen for the endoscope  30  is not round, but instead is formed by the convex outer diameters of the first and second lumens  12 ,  14 , and the inner surface  15  of the flexible tubular member  11 . This results in gaps between the endoscope  30  and the first and second lumens  12 ,  14  and inner surface  15  of the flexible tubular member, which reduces friction between the endoscope and those surfaces. 
       FIG. 12  shows an example first instrument guide  118  for insertion through one of the ports  112  and lumens  12 ,  14 . The first instrument guide  118  has a proximal end  120  that can be coupled to a distal end  122  of handle member  124  ( FIG. 15 ). The first instrument guide  118  may have a distal end  126  that, when extended through an associated lumen  12 ,  14  in the flexible tubular member  11 , can position an instrument disposed therethrough to enable a user, by manipulating the handle member  124 , to perform an operation within the working space  70  formed by the adjustable cage  40 . The illustrated first instrument guide  118  has a single bend “hockey stick” arrangement at the distal end  126 . 
       FIG. 13  shows an example second instrument guide  128  for insertion through one of the ports  112  and lumens  12 ,  14 . The second instrument guide  128  has a proximal end  130  that can be coupled to the distal end  122  of the handle member  124  ( FIG. 15 ). The second instrument guide  128  can have a distal end  132  that, when extended through an associated lumen  12 ,  14  in the flexible tubular member  11 , can position an instrument disposed therethrough to enable a user, by manipulating the handle member  124 , to perform an operation within the working space  70  formed by the adjustable cage  40 . The illustrated second instrument guide  128  has a double bend “cobra” arrangement at the distal end  126 . 
     The instrument guides  118 ,  128  may have a laminated braid construction, including high strain spine strips or wires (e.g., heat shaped nickel titanium or stiff polymer to curve) embedded at the distal ends  126 ,  132  to maintain a strong and resilient end portion. Proximal to the curved tip can be a rigid tube (e.g., metal) from 0.5-3.0 inches long to prevent that section from flexing when the instrument is used to lift a lesion. The distal ends  126 ,  132  can be deflectable to direct an instrument towards the target lesion or to position the distal ends farther away from lesion for better retraction. 
       FIG. 14  shows an example tissue manipulator  134  for insertion through one of the ports  112  and lumens  12 ,  14 . The tissue manipulator  134  has a proximal end  136  that can be coupled to a distal end  138  of the manipulator handle member  140  ( FIG. 16 ). The tissue manipulator  134  can have a distal end  141  that, when extended through an associated lumen  12 ,  14  in the flexible tubular member  11 , can enable a user manipulating the handle member  140  to engage and manipulate tissue within the working space  70  formed by the adjustable cage  40 . 
     It will be appreciated that the first and second instrument guides  118 ,  128  and the tissue manipulator  134  are merely examples of structures that can be disposed through the ports  112  and lumens  12 ,  14  to perform operations within the working space  70  formed by the adjustable cage  40 . Thus, a wide variety of tissue manipulators and instrument guides having shapes different from those described in relation to  FIGS. 12-14  can be used without departing from the present disclosure. In addition, it will be appreciated that the system  10  can be used with “smart” instruments having self-articulating distal working ends (i.e., they do not require the use of instrument guides in order to engage tissue in the working space  70 ). One of ordinary skill in the art will understand that other types of instruments can also be inserted through the instrument guides  118 ,  128 , a non-limiting example list of which includes ultrasound probes and any of a variety of diagnostic, imaging and other types of probes. 
     As, mentioned, during insertion into the body lumen and navigation to the lesion, the actuators  52 ,  54 ,  56 ,  58  can be moved together to retract all of the flexible elements  42 ,  44 ,  46 ,  48  to configure the adjustable cage  40  in the retracted configuration. This configuration can facilitate movement of the system around curves in the body lumen. As will be understood, curvatures in body lumens at or near targeted lesions can cause the adjustable cage  40 , and thus the endoscope  30  and any instruments inserted through the lumens  12 ,  14 , to be biased or wedged against the outside portion of the curve. To counter this, some or all of the flexible elements  42 ,  44 ,  46 ,  48  can be selectively adjusted to center the adjustable cage  40 , and thus the instruments and endoscope  30  with respect to the lesion. For example, one or more of the flexible elements  42 ,  44 ,  46 ,  48  positioned adjacent to such an outside curvature in the body lumen can be tensioned while one or more of the remaining flexible elements can be retracted, thereby flexing the adjustable cage and reshaping the body lumen to center the adjustable cage and the instruments and instrument guides over the lesion. The flexible elements  42 ,  44 ,  46 ,  48  that are compressed can arch outward against the body lumen wall to create an operating and visualization space for working on the target lesion. 
       FIGS. 17-18  show an approach in which a lesion  142  is disposed on the outer curve of a body lumen  146 . By expanding the adjustable cage  40  toward a side of the body lumen opposite that of the lesion  142 , a larger working space  70  can be created for the instrument guide  128  to arch away from the lesion and rotate freely. Specifically, at least one of the flexible elements (e.g., flexible elements  42 ,  44 ) positioned on a side of the adjustable cage  40  facing away from the lesion  142  may be extended (by moving the associated actuators  52 ,  54  toward the adjustable cage  40 ), while the remaining flexible elements (e.g., flexible elements  46 ,  48 ) may be held stationary or may be retracted slightly (by maintaining the associated actuators  56 ,  58  stationary, or moving them slightly away from the adjustable cage  40 ). In addition to expanding the adjustable cage in a direction away from the lesion  142 , this action can cause the cap member  50  to push the lesion  142  away from the distal end  132  of the second instrument guide  128 . This can increase the working space  70  so that forceps (not shown) can extend from the second instrument guide  128  to grasp the lesion  142  and retract the lesion by pulling the forceps back into the second instrument guide. In the illustrated embodiment, a dissector  144  is extendable from the endoscope  30  to dissect or resect the lesion  142  for removal. 
       FIGS. 19-20  show an approach in which a lesion  142  is disposed between inner and outer curve sections of a body lumen  146 . By expanding the adjustable cage  40  toward one side of the body lumen  146 , additional transverse space can be created to center the lesion and the instrument guide  118 . Specifically, at least one of the flexible elements (e.g., flexible elements  42 ,  44 ) positioned on a side of the adjustable cage  40  facing away from the outer curve be extended (by moving the associated actuators  52 ,  54  toward the adjustable cage  40 ), while the remaining flexible elements (e.g., flexible elements  46 ,  48 ) may be held stationary or may be retracted slightly (by maintaining the associated actuators  56 ,  58  stationary, or moving them slightly away from the adjustable cage  40 ). This can centralize the lesion within the working space  70  so that forceps can extend from the first instrument guide  118  to can grasp the lesion  142  and retract the lesion by pulling the forceps back into the first instrument guide. In the illustrated embodiment, a dissector  144  is extendable from the endoscope  30  to dissect or resect the lesion  142  for removal. 
       FIG. 21-22  show an approach in which a lesion  142  is disposed on an inner curve of a body lumen  146 . In this case the first instrument guide  118  (i.e., the “hockey stick” shaped guide) is used to prevent the instrument guide from being wedged against the outer curve of the body lumen  146 , which could otherwise limit movement of the instrument guide. The first instrument guide  118  is positioned a distance away from the lesion  142  so that it can direct a selected instrument directly at the lesion  142 . Thus, at least one of the flexible elements (e.g., flexible elements  42 ,  44 ) positioned on a side of the adjustable cage  40  facing toward the lesion  142  can be extended (by moving the associated actuators  52 ,  54  toward the adjustable cage  40 ), while the remaining flexible elements (e.g., flexible elements  46 ,  48 ) may be held stationary or may be retracted slightly (by maintaining the associated actuators  56 ,  58  stationary, or moving them slightly away from the adjustable cage  40 ). In this position, an instrument can extend from the first instrument guide  118  to assist a dissector  144 , which is extendable from the endoscope  30 , to dissect or resect the lesion  142  for removal. 
       FIG. 23-24  show an approach in which a lesion  142  is disposed on a straight section of a body lumen  146 . By expanding the adjustable cage  40  toward a side of the body lumen opposite that of the lesion  142 , a larger working space  70  can be created for the instrument guide  128  to arch toward the lesion. Specifically, at least one of the flexible elements (e.g., flexible elements  42 ,  44 ) positioned on a side of the adjustable cage  40  facing away from the lesion  142  may be extended (by moving the associated actuators  52 ,  54  toward the adjustable cage  40 ), while the remaining flexible elements (e.g., flexible elements  46 ,  48 ) may be held stationary or may be retracted slightly (by maintaining the associated actuators  56 ,  58  stationary, or moving them slightly away from the adjustable cage  40 ). This can increase the working space  70  so that forceps (not shown) can extend from the second instrument guide  128  to grasp the lesion  142  and retract the lesion by pulling the forceps back into the second instrument guide. In the illustrated embodiment, a dissector  144  is extendable from the endoscope  30  to dissect or resect the lesion  142  for removal. 
     Table 1 provides guidance on the technique used for each scenario and appropriate Tool Guide shape. Shaping and orientation of the adjustable cage  40  involves correlating the orientation of the adjustable cage, instrument guides  118 ,  128  and endoscope  30  to the orientation of the handle  24  and actuators  52 ,  54 ,  56 ,  58 . Therefore, the cap member  50  can have a unique color (i.e. magenta) on the endoscope  30  side (e.g., 12 o&#39;clock) and the same color can be provided on the same side of the handle  24 . Each flexible element  42 ,  44 ,  46 ,  48  can also have color markers visible through the endoscope  30 . In some embodiments, the color markers re disposed on the distal ends of the flexible elements that corresponds with colors of the associated actuators  52 ,  54 ,  56 ,  58 . By viewing the image from the endoscope  30 , the user can determine which flexible element(s)  42 ,  44 ,  46 ,  48  to extend, and which flexible element(s) to retract, and can slide the appropriate actuator(s) either toward or away from the adjustable cage  40  accordingly. 
     
       
         
           
               
             
               
                 TABLE 1 
               
             
            
               
                   
               
               
                 Guide to Cage Shaping and Tool Guide Shape 
               
               
                 Selection for Various Lesion Locations 
               
            
           
           
               
               
               
            
               
                 Lesion Location relative to 
                   
                 Tool Guide Shape 
               
               
                 lumen curvature 
                 Cage Flexion 
                 Selection 
               
               
                   
               
               
                 Outer section of lumen curvature 
                 Towards outer curve 
                 Cobra 
               
               
                 Between Inner and Outer 
                 Towards outer curve 
                 Cobra 
               
               
                 section of curvature 
               
               
                 Inner section of lumen curvature 
                 Towards outer curve 
                 Hockey Stick 
               
               
                 On straight lumen 
                 Towards lesion 
                 Cobra 
               
               
                   
               
            
           
         
       
     
     A non-limiting example method for accessing a lesion  142  using the system  10  can begin with inserting an endoscope  30  through the flexible tubular member  11 . The endoscope  30  may be extended through the opening  71  of the cap member  50  as far as possible. The adjustable cage  40  may be retracted to the second length (i.e., the retracted configuration) by moving all of the actuators  52 ,  54 ,  56 ,  58  way from the adjustable cage as far as possible. The endoscope can be inserted into the body lumen  146  and navigated to the site of interest (i.e., adjacent to a targeted lesion  142 ). The flexible tubular member  11  may then be inserted into the body lumen  146  and navigated to the site of interest until the adjustable cage  40  traverses the lesion  142  as seen through the visualization functionality of the endoscope  30 . It will be appreciated that in some embodiments, the endoscope  30  and flexible tubular member  11  can navigate to the lesion site together, as a unit. 
     The handle  24  can be rotated to rotate the adjustable cage  40  so that the endoscope side of the adjustable cage straddles the lesion  142 . The adjustable cage  40  can be configured in the extended position by moving all of the actuators  52 ,  54 ,  56 ,  58  toward the adjustable cage  40 . The handle  24  may be used to position the cap member  50  just distal to the lesion  142 . One or more of the actuators  52 ,  54 ,  56 ,  58  may be adjusted to position the cap in a desired orientation with respect to the lesion  142 , and to expand the adjustable cage  40  in a manner that provides a desired working space  70  for the instrument guide(s)  118 ,  128  and the endoscope  30  to access the lesion  142 . Table 1 may be used as a guide for shaping of the adjustable cage  40  and for instrument guide shape selection for various lesion locations. 
     If there is a fold in the body lumen  146  in front of lesion  142 , the fold can be grasped using forceps (not shown) inserted through the first instrument guide  118 , and the forceps may be used to push the fold down to expose the lesion  142 . If there is a fold in the body lumen  146  behind the lesion  142 , the fold can be grasped using forceps and the forceps may be retracted into the instrument guide  118 . The instrument guide  118  may then be pushed forward to expose the lesion  142  for resection. An injection needle (not shown) can be inserted through an instrument channel of the endoscope and dye can be injected into the lesion  142 . 
     An appropriate instrument guide  118 ,  128  can be selected based on the criteria of Table 1. A grasper (not shown) can be inserted through the selected instrument guide  118 ,  128  and the two can be inserted through a selected port  112  in the flexible tubular member  11 . The lesion  142  can be grasped using the grasper, and the grasper may be retracted until the jaws of the grasper retract inside the distal end of the instrument guide. Alternatively, the grasper can be extended away from the connected lesion to facilitate subsequent dissection. The instrument guide  118 ,  128  may be twisted to increase retraction (i.e., lift) as needed. 
     A dissector (e.g., dual knife, scissor, or the like) may be extended through a lumen  12 ,  14  in the endoscope  30 . The endoscope  30  may be positioned near the lesion  142 , and the dissector  144  may be advanced to engage the lesion  142 . The endoscope  30  may be used to steer the dissector to the lesion  142 , and the lesion may be separated from the body lumen  146  using the dissector. The grasper along with the instrument guide can then be retracted into its respective lumen to remove the lesion  142 . 
       FIGS. 25-33  illustrate an embodiment of a system  200  for performing minimally invasive procedures in a body lumen. The system  200  may include a flexible tubular member  211  having some or all of the features (e.g., insufflation port(s), lumen(s) for receiving instrument guides and instruments, endoscopes, and the like, construction to facilitate torque transmission, and the like) described in relation to the flexible tubular member  11  of  FIGS. 1-24 . The flexible tubular member  211  may also include a handle (not shown) having some or all of the features described in relation to the handle  24  of  FIGS. 1-24 , including a plurality of actuators similar to the actuators  52 ,  54 ,  56 ,  58  described in relation to  FIGS. 1-24 . An adjustable cage  240  may be disposed at a distal end  213  of the system  200  for positioning within the body lumen adjacent a targeted lesion. 
     As will be discussed, the system  200  is configured to enable a user to access a targeted lesion within a body lumen, and to perform one or more operations on the lesion using any of a variety of instruments disposed through lumens in the flexible tubular member  211  and/or an endoscope  230  disposed through the flexible tubular member  211 . The adjustable cage  240  may include a plurality of flexible elements  242 ,  244 ,  246 ,  248 , each of which can be independently movable by an associated actuator disposed in or on the handle. As with the prior embodiment, independent adjustment of each of the plurality of flexible elements  242 ,  244 ,  246 ,  248  can result in a desired change in shape of the adjustable cage  240 . 
     The adjustable cage  240  of the present embodiment may be used to control the position and orientation of a cap member  250  disposed at a distal end thereof. As will be discussed, a plurality of instruments and/or instrument guides  218 ,  228  may protrude through the cap member  250  to perform one or more operations disposed beyond the cap member. Thus, in contrast to the prior embodiment, the adjustable cage  240  may not itself form a working space within which an operation on the lesion will be formed. Instead, the adjustable cage  240  may function as a steering unit to steer the plurality of instruments and/or instrument guides  218 ,  228  toward a lesion disposed beyond the adjustable cage and the cap member  250 . 
     The adjustable cage  240 , in combination with the handle, may also be used to press the cap member  250  against the lesion and/or tissue adjacent to the lesion, in order to provide the instruments inserted therethrough to perform one or more operations on the lesion. 
     The adjustable cage  240  may include first and second working channels  252 ,  254  coupled between the first and second lumens  212 ,  214  of the flexible tubular member  211  and the cap member  250 . One or more instruments and/or instrument guides  218 ,  228 , inserted through the first and second lumens  212 ,  214 , can be disposed through the first and second working channels  252 ,  254  to protrude from a distal end  256  of the cap member  250 . In one non-limiting example embodiment, the first and second working channels  252 ,  254  comprise flexible polymer tubing that is adhered or otherwise fixed to an inner surface of the cap member  250 . Distal ends (not shown) of the first and second working channels  252 ,  254  may be oriented so that instruments and/or instrument guides disposed therethrough can exit the distal end  256  of the cap member  250  through one or more of the slits  258  formed in the cap member. 
     Although the illustrated embodiment shows two working channels, it is contemplated that greater or fewer working channels can be used. As will be appreciated, the first and second working channels  252 ,  254  may eliminate the need for instrument guides, because the working channels themselves may act as instrument guides, orienting the instruments in a desired manner through adjustment of the position of the cap member  250 . 
     Thus, the system  200  contemplates that a working space is formed distal to the cap member  250 , and that the cap member  250  controls the position and orientation of the instruments inserted through the working channels  252 ,  254 . 
     For embodiments that do not employ instrument guides, a variety of “smart” instruments (i.e., instruments that include their own articulation functionality) can be used, including graspers, knives, retractors and the like. Traditional instruments can also be used, with or without instrument guides as desired. 
     The adjustable cage  240  may also include a connection member  270  coupled between the cap  275  disposed on the distal end  268  of the flexible tubular member  211  and the cap member  250 . In one non-limiting example embodiment, the connection member  270  is a flexible metallic braided tube that provides a desired offset between the distal end  268  of the flexible tubular member  211  and the cap member  250 . The connection member  270  acts as a “spine” for the adjustable cage  240 , to minimize stress placed on the working channels  252 ,  254  during system placement, orientation, and operation. In some embodiments, the connection member  270  may also include a flexible polymer tube  274  (see  FIGS. 27, 31, 32 ) surrounding the flexible metallic braided tube. 
       FIG. 25  shows the adjustable cage  240  is shown in a collapsed configuration. As will be appreciated, the adjustable cage  240  may be positioned in this collapsed configuration when the flexible tubular member  211  is inserted into the body lumen. Once the adjustable cage  240  is navigated through the body lumen and positioned adjacent to a targeted lesion, the user may selectively expand the adjustable cage into an expanded configuration which, as will be described in greater detail later, can position a cap member  250  coupled thereto in a desired orientation and to orient one or more instruments and/or instrument guides  218 ,  228  with respect to a targeted lesion. 
     As shown most clearly in  FIG. 31 , the adjustable cage  240  may comprise a plurality of flexible elements  242 ,  244 ,  246 ,  248 , that can be independently adjustable to enable a user to selectively adjust a size and shape of the adjustable cage. In the illustrated embodiment, the plurality of members  242 ,  244 ,  246 ,  248  comprise a plurality of wires that form a cage. It will be appreciated that although the illustrated embodiment includes four flexible elements, greater or fewer flexible elements can be employed to form the adjustable cage  240 . In addition, although the illustrated embodiment shows the flexible elements as being wires, the flexible elements can be made from any structural elements that can provide the desired functionality as will be described herein. 
     As shown, the plurality of flexible elements  242 ,  244 ,  246 ,  248  each have a distal end  242   a ,  244   a ,  246   a ,  248   a  that is fixedly coupled to the cap member  250 . Proximal ends (not shown) of the plurality of flexible elements  242 ,  244 ,  246 ,  248  are coupled to respective actuators associated with the handle The flexible elements  242 ,  244 ,  246 ,  248  are received within longitudinal openings in the flexible tubular member  211  and exit through openings  260 ,  262 ,  264 ,  266  adjacent a distal end  268  of the flexible tubular member  211 . The plurality of flexible elements  242 ,  244 ,  246 ,  248  can be independently extended and retracted with respect to the distal end  268  of the flexible tubular member  211  by individually actuating the respective actuators of the handle  24 . In this manner, the shape of the adjustable cage  240  can be adjusted to adjust the position and orientation of the cap member  250  so that instruments inserted through the flexible tubular member  211  and the cap member can access a targeted lesion, as will be described in greater detail later. 
     As noted, the cap member  250  may have a generally cylindrical proximal end  257  coupled to the distal ends  242   a ,  244   a ,  246   a ,  248   a  of the plurality of flexible elements  242 ,  244 ,  246 ,  248 . A connection member  270 , including a flexible polymer tube  274  may also be coupled between the distal end  268  of the flexible tubular member  211 , as will be discussed in greater detail later. The distal end  256  of the cap member  250  may have a curved shape configured to facilitating movement of the system  200  through the body lumen. The distal end  256  of the cap member  250  may have an opening  290  ( FIG. 27 ) therethrough sized and shaped to receive the endoscope  230  therethrough. The opening  290  may include a plurality of slits  258  that radiate away from the opening. The slits  258  may allow the opening  290  to flex outwardly to accept the endoscope  230  therethrough, ensuring a snug fit between the cap member  250  and the endoscope to prevent tissue from being pinched between the cap member and the endoscope as the endoscope is moved through the opening.  FIG. 28  shows the endoscope  230  extended through the opening  290 . 
     The cap member  250  may also have a side slit  292  that extends between the proximal and distal ends  257 ,  256  of the cap member. The side slit  292  may allow the endoscope to disengage through the side of the cap member  250  before, during, or after a procedure to allow the user freedom to move the endoscope to a desired position and orientation with respect to a targeted lesion.  FIG. 29  shows the endoscope  230  laterally detached from the cap member  250 . For example, in some embodiments the endoscope  230  may be positioned in or through the cap member  250  during navigation to the lesion and may then be moved outward through the side slit  292  to facilitate resection of the lesion. 
       FIG. 30  shows the adjustable cage  240  in an expanded configuration. In the illustrated configuration one of the flexible elements  244  is extended while the other flexible elements  242 ,  246 ,  248  are either maintained in place or retracted. This results in the adjustable cage being bowed on one side to provide a desired orientation of the cap member  250 . Since the plurality of flexible elements  242 ,  244 ,  246 ,  248  are independently extendable/retractable, the adjustable cage  240  is infinitely adjustable by the user to provide a desired orientation of the cap member  250  depending on the shape of the body lumen and the position of the targeted lesion. This provides the user with an enhanced array of options for accessing a lesion using one or more instruments and an endoscope  30  disposed through the flexible tubular member  211 . 
     As can be seen in  FIG. 28 , endoscope  230  is extendible through the adjustable cage  240  and also through the opening  290  in the cap member  50 . As shown in  FIG. 30 , first and second working channels  252 ,  254  are also extendable through the adjustable cage  240  and the opening  290  in the cap member  250 . The first and second working channels  252 ,  254  can receive first and second instrument guides  218 ,  228  which can receive first and second instrument therethrough. As will be appreciated, the disclosed arrangement can enable a variety of visualization and tissue manipulation functions to be performed on a targeted lesion disposed adjacent to the cap member  250 . 
     A cap  275  may be disposed on or over the distal end  268  of the flexible tubular member  211 . As shown in  FIG. 31 , the plurality of flexible elements  242 ,  244 ,  246 ,  248  are received through respective openings  276 ,  278 ,  280 ,  282  in the cap  275 . The cap  275  can also include an opening  284  for receiving the endoscope  230  therethrough, and respective openings  286 ,  288  aligned with the first and second lumens  212 ,  214  in the flexible tubular member  211 . 
     As previously noted, the system  200  can include a handle having actuators that are configured and have the same functionality to individually actuate the plurality of flexible elements  242 ,  244 ,  246 ,  248  as described in relation to  FIGS. 1-25 . As discussed, by enabling the individual flexible elements  242 ,  244 ,  246 ,  248  to be extended, retracted, or held in place via selective activation of one or more of the actuators, the adjustable cage  240  can be lengthened (i.e., extended), shortened (i.e., retracted), and/or otherwise adjusted to achieve a variety of configurations appropriate for positioning the cap member  250  in a desired orientation. 
     During insertion of the system  200  into the body lumen, and while navigating the adjustable cage  240  to a target lesion, the actuators on the handle can be allowed to “ride free” with respect to the handle to allow the plurality of flexible elements  242 ,  244 ,  246 ,  248  to naturally flex as the system passes the curves of the body lumen. In some embodiments, the distal tip of the endoscope may be slightly offset (e.g., ½ centimeter) from the cap member  250  during navigation of the body lumen in order to provide a degree of flexibility between the two. In some embodiments, the cap member  250  can be manipulated as it is moved through the body lumen in order to make it easier to pass the natural curves of the lumen. 
     Once the adjustable cage  240  has been navigated within the body lumen to a desired position with respect to the targeted lesion, the actuators can be adjusted to adjust the shape of the adjustable cage  240  to orient the cap member  250  toward the lesion. 
     The flexible elements  242 ,  244 ,  246 ,  248  can be made from the same or similar materials as those described in relation to the flexible elements of  FIGS. 1-24 . In addition, the flexible elements  242 ,  244 ,  246 ,  248  can be constrained within respective braided tubes within the flexible tubular member  211  in the same manner as described in relation to  FIGS. 1-24 . 
     A variety of instrument guides, instruments, and tissue manipulators, similar to those described in relation to  FIGS. 1-24  can be used with the system  200 . 
     A non-limiting example method for accessing a lesion using the system  200  may begin with inserting an endoscope  230  through the flexible tubular member  211 . The endoscope  230  may be extended through the opening  290  of the cap member  250  as far as possible. The endoscope can be inserted into the body lumen and navigated to the site of interest (i.e., adjacent to a targeted lesion). The flexible tubular member  211  may then be inserted into the body lumen and navigated to the site of interest until the cap member  250  is positioned adjacent the lesion as seen through the visualization functionality of the endoscope  230 . In some embodiments, the flexible tubular member  211  covers the endoscope  230  (up to the cap member  250 ) during navigation. 
     The handle can be rotated to rotate the adjustable cage  240  so that the endoscope side of the adjustable cage straddles the lesion. The handle may be used to adjust the position of the cap member  250  adjacent to the lesion. One or more of the actuators may be adjusted to expand the adjustable cage  240  in a manner that provides a desired position of the cap member  250  with respect to the lesion. If there are folds in front of or behind the lesion, forceps disposed through one of the working channels  252 ,  254  can be used to expose the lesion in the manners described. 
     The appropriate instrument guide  218 ,  228  can be selected. A grasper (not shown) can be inserted through the selected instrument guide  218 ,  228  and the two can be inserted through a selected lumen  212 ,  214  in the flexible tubular member  211 . The lesion can be grasped using the grasper, and the grasper may be retracted until the jaws of the grasper retract inside the distal end of the instrument guide. The instrument guide  218 ,  228  may be twisted to increase retraction (i.e., lift) as needed. 
     A dissector (e.g., dual knife, scissor, or the like) may be extended through a lumen in the endoscope  230 . The endoscope  230  may be positioned near the lesion, and the dissector may be advanced to engage the lesion. The endoscope  230  may be used to steer the dissector to the lesion, and the lesion may be separated from the body lumen using the dissector. The grasper and instrument guide may be retracted into the associated lumen  212 ,  214  in the flexible tubular member  211  to remove the lesion. 
     All of the devices and/or methods disclosed and claimed herein can be made and executed without undue experimentation in light of the present disclosure. While the devices and methods of this disclosure have been described in terms of preferred embodiments, it may be apparent to those of skill in the art that variations can be applied to the devices and/or methods and in the steps or in the sequence of steps of the method described herein without departing from the concept, spirit and scope of the disclosure. All such similar substitutes and modifications apparent to those skilled in the art are deemed to be within the spirit, scope and concept of the disclosure as defined by the appended claims.