Abstract:
A positioning device is configured to selectively position or otherwise manipulate one or more organs within the body of a subject. The positioning device includes a shaped expandable element that is configured to be selectively transitioned between an unexpanded, or collapsed, state and an expanded state. While in the expanded state, the expandable element repositions or otherwise manipulates an organ. Systems that include positioning devices are also disclosed, as are methods for positioning or otherwise manipulating organs.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    A claim for the benefit of priority to the Feb. 28, 2014 filing date of U.S. Provisional Patent Application No. 61/946,392, titled EXPANDABLE DEVICES FOR POSITIONING ORGANS (“the &#39;392 Provisional Application”), is hereby made pursuant to 35 U.S.C. §119(e). The entire disclosure of the &#39;392 Provisional Application is hereby incorporated herein. 
     
    
     TECHNICAL FIELD 
       [0002]    This disclosure relates generally to devices for selectively positioning or otherwise manipulating organs (e.g., hollow organs, organs adjacent to internal body cavities, etc.) within the body of a subject. A positioning device according to this disclosure may include an expandable element with a shape that will position a hollow organ, such as an esophagus, in a desired manner. Systems that include organ positioning devices are also disclosed, as are methods for positioning organs. 
       SUMMARY 
       [0003]    A positioning device according to this disclosure may be configured for introduction into a hollow organ or an internal body cavity and against a surface of an organ. The positioning device may include a shaft and an expandable element. The shaft may have a longitudinal axis, which may be the longitudinal axis of the positioning device. The shaft may be configured to enable introduction of the positioning device and, more specifically, its expandable element, into the body of a subject and into a hollow organ that is to be repositioned or otherwise manipulated. Alternatively, the shaft may be introduced into an internal cavity within a subject&#39;s body adjacent to at least one organ that is to be repositioned or otherwise manipulated. 
         [0004]    The expandable element is positioned along a length of the shaft. It may be located at an intermediate position along a length of the shaft, with portions of the shaft located proximal to and distal to the expandable element. Alternatively, the expandable element may be located at a distal end of the shaft. 
         [0005]    The expandable element may have an unexpanded state and an expanded state. The unexpanded state, or collapsed state, of the expandable element may facilitate its introduction into a subject&#39;s body and into the hollow organ or internal cavity, as well as its removal from the hollow organ or internal cavity and the body. While in the unexpanded state, the expandable element may be flaccid or substantially flaccid and, thus, easily manipulated (e.g., bent, otherwise conform to a desired shape, etc.). 
         [0006]    The expanded state of the expandable element may enable it to assume a desired shape, which may provide the positioning device with an asymmetrical structure. In some embodiments, the expandable element may include a divergent section, a spacing section and, optionally, a convergent section. The divergent section of the expandable element may at least partially diverge from the longitudinal axes of the shaft and the positioning device while in the expanded state. The spacing section of the expandable element, which is distal to the divergent section, may be configured to move, stretch or otherwise manipulate the tissues of a hollow organ in which the expandable element is disposed or an organ against which the expandable element is positioned and, thus, to modify the position and/or shape of the organ. In embodiments where the positioning device includes a convergent section, the convergent section may reinforce the new position and/or shape of a portion of the hollow organ in which the expandable section resides or against which the expandable section has been positioned, as defined at least in part by the spacing section. The abilities of the divergent section, the spacing section and any optional convergent section to move, reshape or otherwise manipulate an organ or a portion thereof may, in some embodiments, result from a substantial rigidity (e.g., the rigidity provided by a gas inflated (e.g., to a pressure of about 8 atm. to about 15 atm., etc.) or fluid inflated element, etc.) or a rigidity of the expandable element while in its expanded state. 
         [0007]    In use, the expandable element of a positioning device, while in its unexpanded state, may be introduced into the body of a subject, and into an interior of a hollow organ or into an internal cavity of the body. In some embodiments, the expandable element may be placed at a particular location and in a particular orientation within the hollow organ or internal cavity. Once the expandable element is in place within the hollow organ or internal cavity, it may be expanded. Expansion of the expandable element may move, stretch or otherwise manipulate some or all of the hollow organ or internal cavity. With an organ moved or otherwise manipulated in a desired manner, other procedures may be performed. After those procedures are complete, the expandable element may be returned to its unexpanded state, which may reverse movement other manipulation of part or all of the organ. The expandable element may then be removed from the hollow organ or internal cavity, and the expandable element and the positioning device may be removed from the body of the subject. 
         [0008]    Other aspects, as well as features and advantages of various aspects, of the disclosed subject matter will become apparent to those of ordinary skill in the art through consideration of the ensuing description, the accompanying drawings and the appended claims. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0009]    In the drawings: 
           [0010]      FIG. 1  illustrates an embodiment of a positioning device, which includes a shaft and an expandable element positioned over an intermediate portion of the shaft, with the expandable element in an unexpanded state; 
           [0011]      FIG. 2  illustrates the embodiment of positioning device shown in  FIG. 1 , with the expandable element in an expanded state; 
           [0012]      FIG. 3  depicts another embodiment of positioning device, which includes a shaft and an expandable element positioned over a distal portion of the shaft, with the expandable element in an unexpanded state; 
           [0013]      FIG. 4  depicts the embodiment of positioning device shown in  FIG. 3 , with the expandable element in an expanded state; 
           [0014]      FIG. 5  shows yet another embodiment of positioning device, which includes a shaft and another embodiment of expandable element on the shaft, with the expandable element in an unexpanded state; 
           [0015]      FIG. 6  shows the embodiment of positioning device depicted by  FIG. 5 , with the expandable element in an unexpanded state; and 
           [0016]      FIGS. 7 through 9  are radiographic images of use of an embodiment of positioning device according to this disclosure in a human esophagus. 
       
    
    
     DETAILED DESCRIPTION 
       [0017]    With reference to  FIGS. 1 and 2 , an embodiment of a positioning device  10  that incorporates teachings of this disclosure is illustrated. The positioning device  10 , which is configured to move and/or manipulate a portion of a hollow organ within which it is positioned, includes a shaft  20  and an expandable element  30 . 
         [0018]    The shaft  20  of the positioning device  10  comprises an elongated element, and may include a longitudinal axis L, which may define a longitudinal axis of the positioning device  10 . The shaft  20  is configured to enable introduction of the expandable element  30  into the body of a subject, and placement of the expandable element  30  at a desired location and in a desired orientation within the body; for example, within a hollow organ in the body. The shaft  20  may have sufficient flexibility to enable its movement along curved, even tortious, paths through the body of a subject, to enable it to conform to the shape(s) of structures (e.g., organs, etc.) within which or against which it is positioned and/or to enable it to at least partially conform to the shape of the expandable element  30 . 
         [0019]    Without limitation, the shaft  20  may comprise a catheter. More specifically, the shaft  20  may comprise an over-the-wire (OTW) catheter, which may be configured to be placed over and introduced into the subject&#39;s body along a guide wire. Even more specifically, the shaft  20  may comprise a 6 French (F) to 9 F catheter that is configured for introduction on a 60 PPI to 90 PPI large braid guide wire with an outer diameter of up to about 0.038 inch. 
         [0020]    The shaft  20  may be configured to enable remote expansion and retraction of the expandable element  30 . In embodiments where the shaft  20  comprises a catheter, the shaft  20  may include a lumen that enables an inflation medium, such as a gas or mixture of gases, air or a liquid, to be introduced into the expandable element  30  and/or withdrawn from the expandable element  30 . In other embodiments, the shaft  20  may be configured to accommodate one or more elements (e.g., a control wire, etc.) that enable mechanical expansion and/or retraction of the expandable element  30 . 
         [0021]    As illustrated by  FIGS. 1 and 2 , respectively, the expandable element  30  of the positioning device  10  has an unexpanded state and an expanded state. In its unexpanded state, which is depicted by  FIG. 1 , the expandable element  30  may reside on an outer surface  22  of the shaft  20  with extending substantially beyond the outer surface  22 . As shown in  FIG. 2 , in its expanded state, the expandable element  30  may extend beyond the outer surface  22  of the shaft  20 . In addition, when the expandable element  30  expands, it may diverge from the longitudinal axes L of the shaft  20  and the positioning device  10 . 
         [0022]    In the embodiment depicted by  FIGS. 1 and 2 , the expandable element  30  includes, from its proximal side to its distal side, a divergent section  32 , a spacing section  34  and a convergent section  36 . The divergent section  32  may be configured to move a portion of a hollow organ within which the divergent section  32  resides out of its normal location or, in the case of an elongated organ (e.g., an esophagus, a large intestine, a urethra, etc.), out of the normal path of the elongated organ. The spacing section  34 , which is distal to the divergent section  32 , is configured to hold a portion of an organ within which it resides in a particular position and/or in a particular shape. The convergent section  36 , which is adjacent to the distal side of the spacing section  34 , may be configured to hold the distal side of the spacing section  34  in place. Optionally, the convergent section  36  may be configured to accommodate organs or other structures within the body of a subject. 
         [0023]    Various transitions, or bends, between differently oriented sections of the expandable element  30  (e.g., the transition between the divergent section  32  and the spacing section  34 , the transition between the spacing section  34  and the convergent section  36 , etc.) may be smooth. The smoothness of one or more transitions may be configured to reduce or eliminate the likelihood of trauma (i.e., a transition may be atraumatic) during and after placement of the expandable element  30  in its expanded state. In some embodiments, a transition, or bend, may comprise a curve. In other embodiments, a transition, or bend, may include outer corners that are radiused. 
         [0024]    In a specific embodiment, in which the positioning device  10  and its expandable element  30  are configured for insertion into and manipulation of a human esophagus, the expandable element  30  may have a length of about 14 cm to about 16 cm, with the spacing section  34 , which is located centrally along a length of the expandable element  30 , being about 10 cm long. The divergent section  32  and the convergent section  36  may be configured to move the spacing section  34  laterally (in the orientation depicted by  FIGS. 1 and 2 ) to a location that is substantially parallel to the longitudinal axis L, but with a longitudinal axis L 34  of the spacing section  34  being offset by about 15 mm from the longitudinal axis L. Upon placing the expandable element  30  in its expanded state, it may have an outer diameter of about 8 mm to about 12 mm. 
         [0025]    The expandable element  30  may, in some embodiments, include one or more radiopaque features  40 , which may enable a clinician to determine the position and, optionally, the orientation of the expandable element  30  within a hollow organ of a subject&#39;s body. In other embodiments, the expandable element  30  may comprise a radiopaque material (e.g., in embodiments where the expandable element  30  comprises a mesh, etc.). 
         [0026]    As suggested previously herein, the expandable element  30  may be configured to be inflated with an inflation medium, such as a gas or mixture of gases, air or a liquid. An expandable element  30  that is configured for inflation may include ends  31   P  and  31   D  that are sealed against the shaft  20 . The shaft  20  of a positioning device  10  with an inflatable expandable element  30  may include an inflation/deflation lumen  24  that communicates with an interior of the expandable element  30  and, thus, introduces an inflation medium into the expandable element  30  and removes the inflation medium from the expandable element  30  by way of one or more apertures (not shown) that extend through a wall of the shaft  20 , from the inflation/deflation lumen  24  of the shaft  20  to an exterior of the shaft  20 . 
         [0027]    An inflatable expandable element  30  may be shaped in a desired manner, such as that depicted by  FIGS. 1 and 2 . Cross-sectionally, the inflatable element  30  may circular, elliptical, have a tear shape, or have any other shape that will cause little or no trauma during and following expansion of the expandable element  30 . Accordingly, the expandable element  30  may be formed from a material that can be shaped as desired. Without limitation, the material of an inflatable expandable element  30  may be moldable, capable of being welded with heat or ultrasonically, or otherwise formed into a desired shape. In addition, the material from which the expandable element  30  is formed may be compliant, semi-compliant or substantially non-compliant when the expandable element  30  is in its expanded state. Examples of suitable materials for use as the expandable element  30  include, but are not limited to, polyethylene, polyethylene terephthalate and polyurethane. 
         [0028]    As indicated previously herein, suitable media for expanding inflatable embodiments of expandable elements  30  include gases, gas mixtures and air. Alternatively, the medium that is used to inflate an inflatable expandable element  30  may comprise a saline solution. In some embodiments, the saline solution may include a radio-opaque material, such as barium or a barium salt. 
         [0029]    As an alternative to inflatable expandable elements, an expandable element  30  may be formed from a shaped mesh that surrounds at least a portion of the shaft  20 . Without limitation, a shaped mesh may be formed from stainless steel, nitinol or any other suitable material. The mesh may be formed (e.g., annealed, etc.) to substantially conform to the shape and dimensions of the shaft  20 , to enable the expandable element  30  to reside on the shaft  20  when the expandable element  30  is in its unexpanded state. The mesh may also be formed to impart the expandable element  30  with a predetermined shape and dimensions when put in its expanded state. 
         [0030]    An expandable element  30  that is formed from or otherwise includes a shaped mesh may be mechanically expanded by any suitable, known means for expansion, such as one or more elements that introduce tension into the shaped mesh to cause it to expand, and that enable the shaped mesh to collapse when the tension is released, or relaxed. As a non-limiting example, an expandable element may include one or more control wires  26  that are configured to mechanically expand and collapse the expandable element  30 . Each control wire  26  may comprise a somewhat rigid element that may extend through a lumen  24  of the shaft  20 , and may be actuated (i.e., pulled and/or pushed) from a location at or near a proximal end of the shaft  20 . As the positioning device  10  is being introduced into the body of a subject, each control wire  26  may be pushed forward to a position that maintains the expandable element  30  in its unexpanded state around and close to the shaft  20 . When the expandable element  30  is at an appropriate location within a hollow organ, one or more control wires  26  may be pulled to expand one or more sections of the expandable element  30  a desired extent. Once use of the positioning device  10  is no longer needed (e.g., when deflection or other reshaping of the hollow organ is no longer needed, etc.), each control wire  26  may be pushed, which will cause the expandable element to collapse to its unexpanded state, thereby facilitating removal of the expandable element  30  and the remainder of the positioning device  10  from the hollow organ. 
         [0031]    Some embodiments of expandable elements  30  may include individually, or separately, inflatable sections (e.g., divergent section  32 , spacing section  34 , convergent section  36 , etc., may be configured to be inflated and deflated independently from one another). In embodiments where the sections  32 ,  34 ,  36  of the expandable element  30  are individually inflatable, each section  32 ,  34 ,  36  may communicate with a separate inflation/deflation lumen  24  of a catheter that forms at least a part of the shaft  20 . In other embodiments, the sections  32 ,  34 ,  36  may be individually expandable and/or retractable by dedicated actuators (e.g., pull wires, etc.). 
         [0032]    Expandable elements  30  with separately expandable sections  32 ,  34 ,  36  may enable a clinician to selectively expand the expandable element  30  in two or more sequences. As an example, and with continued reference to  FIGS. 1 and 2 , the spacing section  34  may be expanded first, causing the spacing section  34  to occupy space within the hollow organ. After the spacing section  34  has been at least partially expanded, one or both of the divergent section  32  and the convergent section  36  may be expanded to move the spacing section  34  and the portion of the hollow organ within which the spacing section  34  resides. Such a configuration may provide for increased control over the manner in which a portion of a hollow organ or an entire hollow organ is manipulated, including, without limitation, the distance the hollow organ is diverted or otherwise moved from its original location. 
         [0033]    Turning now to  FIGS. 3 and 4 , an embodiment of positioning device  10 ′ is illustrated that includes an expandable element  30 ′ that resembles the embodiment of expandable element  30  shown in  FIGS. 1 and 2 . The shaft  20 ′ of the positioning device  10 ′ is, however, configured to be introduced into a body of a subject, or into a hollow organ within a body of a subject, without the need for a guide wire. Accordingly, the shaft  20 ′ may lack a lumen  22  ( FIGS. 1 and 2 ) that accommodates a guide wire, but may include one or more lumens  24 ′ that enable expansion and/or contraction of the expandable element  30 ′ (e.g., by inflation/deflation, by way of a control wire or other control mechanism, etc.). The shaft  20 ′ of the positioning device  10 ′ may, therefore, lack a lumen for receiving a guide wire (although it may include one or more lumens  24  for inflating/deflating the expandable element  30  or sections thereof or one or more lumens  24  for accommodating control wires  26  or other elements for expanding and contracting the expandable element  30  or sections thereof). 
         [0034]    Referring now to  FIGS. 5 and 6 , yet another embodiment of positioning device  10 ″ is shown. The positioning device  10 ″ includes an embodiment of expandable element  30 ″ that comprises a divergent section  32 ″ and a spacing section  34 ″, but lacks a convergent section  36  ( FIGS. 1 and 2 ). 
         [0035]    In use, as shown in  FIGS. 7 through 9 , a positioning device  10  (or any other embodiment of positioning device) according to this disclosure, with its expandable element  30  in an unexpanded state (see, e.g.,  FIG. 7 ) may be inserted into a body of a subject and introduced to a desired location within the subject&#39;s body (e.g., into a hollow organ; into a long organ, such as an esophagus E, a large intestine, a urethra, etc.; into a cavity; etc.). The particular location and, optionally, the particular orientation of the expandable element  30  within the subject&#39;s body may be determined during or after insertion by any suitable technique (e.g., radiography, etc.). If necessary, the position and/or orientation of the expandable element  30  may be adjusted until it is at a desired location and in a desired orientation. 
         [0036]    With the expandable element  30  at an appropriate location within the subject&#39;s body, the expandable element  30  may be expanded, as shown in  FIG. 8 , to manipulate the body; for example, the organ within which the expandable element  30  resides or organs that are adjacent to a cavity within which the expandable element resides (e.g., the esophagus E, etc.). The manner in which the expandable element  30  is expanded (e.g., the order in which its sections  32 ,  34 ,  36  are expanded, the extent to which the expandable element  30  or one or more of its sections  32 ,  34 ,  36  are expanded, etc.) may be controlled. Without limitation, the expandable element  30  may be expanded in a manner that minimizes trauma, in a manner that provides desired movement or reshaping of the organ in which the expandable element  30  resides, etc. In some embodiments, expansion of the expandable element  30  may be visualized (e.g., by radiography, etc.) to confirm that the manner and/or extent of expansion provides one or more desired results (e.g., minimization of trauma, reshaping and/or movement to a desired extent, reshaping and/or movement to a desired extent, etc.). An expandable element  30  and the manner in which it is placed in its expanded state may be configured to move or otherwise manipulate a portion of a long, hollow organ with minimal or no movement of portions of the long, hollow organ that are proximal and distal to the expandable element  30 ; i.e., without distending the long, hollow organ. 
         [0037]      FIG. 9  shows the movement achieved between the orientation of expandable element  30  depicted by  FIG. 7  (unexpanded) and the orientation of expandable element  30  depicted by  FIG. 8  (expanded). In the embodiment illustrated by  FIGS. 7 through 9 , the esophagus E ( FIGS. 7 and 8 ) has been moved from a first position E 1 , in which the esophagus E is adjacent to the left atrium of the heart, to a second position E 2 , which is about 32 mm away from the first position E 1  and which is spaced apart from the left atrium of the heart. 
         [0038]    With the expandable element  30  holding the organ in a manipulated state, another procedure may be conducted. As a non-limiting example, an expandable element  30  may deflect an appropriate portion of an esophagus away from the left atrium of the heart during a left atrial ablation procedure. As another non-limiting example, an expandable element  30  may deflect an appropriate portion of a large intestine or a urethra away from a prostate during biopsy or surgical treatment of a prostate. 
         [0039]    Once the surgical procedure is complete or manipulation of the organ is no longer needed, the expandable element  30  may be collapsed around the shaft  20  of the positioning device  10 . The expandable element  30  and the remainder of the positioning device  10  may then be removed from the subject&#39;s body. 
         [0040]    Although the foregoing disclosure provides many specifics, these should not be construed as limiting the scope of any of the ensuing claims. Other embodiments may be devised which do not depart from the scopes of the claims. Features from different embodiments may be employed in combination. The scope of each claim is, therefore, indicated and limited only by its plain language and the full scope of available legal equivalents to its elements.