Abstract:
The disclosure generally relates to methods and devices for removing a blockage from an anatomical passageway, for example thrombus or clot from a blood vessel. Devices and methods are provided for removing a blockage from an anatomical passageway. For example, a braided funnel is provided that may be placed adjacent a blockage. The braided funnel may be attached to an elongate tube and the blockage may be aspirated through the tube.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims the benefit of U.S. Provisional Application Ser. No. 62/115,262, filed Feb. 12, 2015 entitled Partially Covered Braided Funnel Aspiration Catheter, which is hereby incorporated by reference in its entirety. 
     
    
     FIELD 
       [0002]    The disclosure generally relates to methods and devices for removing a blockage from an anatomical passageway, for example thrombus or clot from a blood vessel. 
       SUMMARY 
       [0003]    Devices and methods are provided for removing a blockage from an anatomical passageway. For example, a braided funnel is provided that may be placed adjacent a blockage. The braided funnel may be attached to an elongate tube and the blockage may be aspirated through the tube. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0004]      FIG. 1  presents an apparatus according to one example; 
           [0005]      FIG. 2  presents a funnel catheter having a flare on a distal end and closed braid ends in an un-bunched configuration; 
           [0006]      FIG. 3  presents the funnel catheter of  FIG. 2  in a bunched-up configuration; 
           [0007]      FIG. 4  presents a funnel catheter having a flare on a distal end and open braid ends in an un-bunched configuration; 
           [0008]      FIG. 5  presents a funnel catheter having open braid ends in an un-bunched configuration; 
           [0009]      FIG. 6  presents a first step in an example of a method; 
           [0010]      FIG. 7  presents a second step in an example of a method; 
           [0011]      FIG. 8  presents a third step in an example of a method; 
           [0012]      FIG. 9  presents a fourth step in an example of a method; 
           [0013]      FIG. 10  presents a fifth step in an example of a method; 
           [0014]      FIG. 11  presents a sixth step in an example of a method; 
           [0015]      FIG. 12  presents a seventh step in an example of a method; 
           [0016]      FIG. 13  presents an eight step in an example of a method; and, 
           [0017]      FIG. 14  presents a ninth step in an example of a method. 
       
    
    
     DESCRIPTION 
       [0018]    Various aspects of the examples are presented in  FIGS. 1-14 , which are not drawn to any particular scale, and wherein like components in the numerous views are numbered alike. Referring now to  FIGS. 1 and 2 , a funnel catheter  100  for aspirating a blockage, for example thrombus, from an anatomical passageway is presented. The funnel catheter  100  comprises an elongate tube  102  defining a longitudinal axis  104 , a proximal tube end  106 , a distal tube end  108 , and a lumen  110  along the longitudinal axis  104  from the proximal tube end  106  to the distal tube end  108 , the proximal tube end  106  being adapted to attach to an aspiration device  10 , for example a syringe. The funnel catheter  100  may also have a braided funnel  112  defining an interior volume  114  and having a proximal funnel portion  116  and a distal funnel portion  118 . The proximal funnel portion  116  may be attached to the distal tube end  108  with the lumen  110  in fluid communication with the interior volume  114 . The proximal funnel portion  116  may be funnel-shaped with a smallest diameter  134  proximate the distal tube end  108  that approximates the outer diameter of the distal tube end  108 . The distal funnel portion  118  defines a distal funnel end  120 . The distal funnel end  120  may terminate with a radially outward flare  122 . A cover  124  may be provided on the proximal funnel portion  116  but not on the distal funnel portion  118 . The cover  124  may completely cover the proximal funnel portion  116 . 
         [0019]    Referring now to  FIGS. 2 and 3 , the outward flare  122  engages the inside of the anatomical passageway  14  thereby causing the distal funnel portion  118  to axially bunch up against the cover  124  and have an increased radial compression strength relative to an un-bunched configuration. Movement of the braided funnel  112  in the distal direction, indicated by arrow  130 , causes the distal funnel portion to bunch-up against the cover  124 . For example, after deployment the braided funnel  112  is unconstrained and expands, and the outward flare  122  engages the inside of an anatomical passageway  14 . Moving the braided funnel in the distal direction  130  causes the distal funnel portion  118  to axially bunch up against the cover  124  because the outward flare  122  engages the anatomical passageway  14 , which fixes the distal funnel end  120  to the wall  16  of the anatomical passageway  14 . Further pushing the braided funnel  112  in the distal direction  130  causes it to bunch up (contract) in the longitudinal direction and expand in the transverse direction and have an increased radial compression strength relative to an un-bunched configuration. It forms a ring-like structure  126 . The ring-like structure  126  may also increase radiopacity relative to the un-bunched configuration. 
         [0020]    An increased radial compression strength is advantageous. The anatomical passageway presses down upon the braided funnel  112  and the increased compression strength resists this better than a conventional braided structure. Also, when removing a blockage, forces may tend to push a conventional braided structure to one side or another. The braided funnel  112  better resists these forces and helps maintain a seal with the wall  132 . 
         [0021]    The proximal funnel portion  116  may be funnel shaped including generally conical shaped. The distal funnel portion  118  may be a cylinder, or other shape that will bunch up and form a ring-like structure  126 , as described above. For example, a shape that complements an artery shape may be desirable. A triangular shape may be desirable a heart valve. An oblong shape may be desirable in vessels with anatomical anamolies, for example where a ligament crosses a blood vessel. As a frame of reference these shapes are in cross-section relative to the longitudinal axis  104 . 
         [0022]    Referring again to  FIG. 1 , the sheath  12  is percutaneously inserted into an anatomical passageway  14 , for example a blood vessel. The braided funnel  112  and the elongate tube  102  may be disposed within the sheath  12  prior to the sheath  12  being inserted into the anatomical passageway  14 . Alternatively, the braided funnel  112  and the elongate tube may be disposed within the sheath  12  after the sheath  12  is inserted into the anatomical passageway  14 . The sheath  12  may have a connector  16  on a proximal end and the funnel catheter  100  may pass through the connector  16 . The connector may have a hemostatic valve through which the elongate tube  102  and the braided funnel  112  in a collapsed configuration are passed, for example a Touhy Borst adapter or a Captor® hemostatic valve (Cook Medical, Bloomington, Ind., USA). If used in a vein there may not be a need for a seal because pressure is low there is little if any leakage. 
         [0023]    The aspiration device  10  may be in fluid communication with the proximal tube end  106 . The aspiration device  10  may be attached to the proximal tube end  106  by a fitting  128  for example, which may be a luer fitting. The aspiration device  10  may be for example a vacuum pump, a VacLok® syringe (Merit Medical Systems, South Jordan, Utah, USA) or a mechanically assisted aspiration syringe with a one way check-valve. 
         [0024]    In  FIG. 2 , the distal funnel end  120  of the braided funnel  112  comprises closed braid ends  132 . The wires bend back into the braid structure. A single wire braid, for example, exhibits this characteristic. Referring to  FIG. 4 , funnel catheter  200  is presented having a braided funnel  212  wherein the distal funnel end  220  comprises open wire terminations  232  that are exposed wire ends. The exposed wire ends present a rougher surface to the inside of the anatomical passageway  14 , which helps keep the distal funnel end  12  from slipping as the braided funnel  112  is moved in the distal direction.  FIG. 5  presents a funnel catheter  300  that does not have an outward flare  122  but it comprises a braided funnel  312  wherein the funnel end  320  comprises open wire terminations  332  that are exposed wire ends. As before, the exposed wire ends present a rougher surface that causes the funnel end  320  to engage the inside of the anatomical passageway  14  without the outward flare  122  shown in  FIGS. 2 and 3 . 
         [0025]    As shown in  FIGS. 2-5 , the cover  124  may completely cover the proximal funnel portion  116 . The proximal funnel  116  portion may end ata first plane  136  that may be transverse, for example perpendicular, to the longitudinal axis  104 , the cover  124  terminating at the first plane  136 . Where the cover  124  terminates may define the location of the first plane  136  along the longitudinal axis  104 . The distal funnel portion  118  may terminate at a second plane  138  that may be transverse, for example perpendicular, to the longitudinal axis  104 . These features may also be applied to all of the example embodiments described herein and may be implemented alone or in combination. 
         [0026]    The braided funnel  112 ,  212 , or  312  may be formed from a wire, for example metals such NiTi, CoCr, stainless steel, and plastics such as PET, Nylon, PEEK Polymide, PTFE, UHMWPE. Metal wires may have a diameter of 0.002 inch to 0.006 inch. Plastic wires may have a diameter of 0.020 inch to 0.060 inch. Of course larger and smaller diameters are contemplated. The elongate tube  102  may be formed from plastic, for example a plastic extrusion. Examples of plastics include nylon and polyurethane without limitation to these materials. The proximal funnel portion  116  may be covered with a thermoplastic material on its proximal end and the braided funnel  112 ,  212 , or  312  may be bonded to the distal tube end  108  by heating the thermoplastic material and fusing the proximal funnel portion  116  to the distal tube end  108 . 
         [0027]    The distal funnel portion  118  may have a diameter  140  that is 1 mm to 2 mm larger than the inside diameter of the anatomical passageway. The outward flair  122  may a diameter 1 mm to 2 mm larger than the distal funnel portion  118 . Alternatively, the diameter  140  may approximate the inside diameter of the anatomical passageway and the outward flair  122  may exceed the diameter  140  by 1 mm to 2 mm. These dimensions are examples and other dimensions are possible depending on the application. 
         [0028]    Referring now to  FIGS. 6 through 14  a method of using a funnel catheter is presented. Although shown with funnel catheter  100 , the method may be performed with other funnel catheters, for example funnel catheters  200 , or  300 . The method comprises inserting the funnel catheter into an anatomical passageway  14 , as shown in  FIG. 6 . Typically, this is done percutaneously. As previously described, the funnel catheter  100  comprises the elongate tube  102  defining the longitudinal axis  104 , the proximal tube end  106 , the distal tube end  108 , and the lumen  110  along the longitudinal axis  104  from the proximal tube end  106  to the distal tube end  108 . The braided funnel  112  defines the interior volume  114  and has the proximal funnel portion  116  and the distal funnel portion  118 . The proximal funnel portion is attached to the distal tube end  108  with the lumen  110  in fluid communication with the interior volume  114 . The proximal funnel portion  116  is funnel-shaped with a smallest diameter proximate the distal tube end  108 . The distal funnel portion  118  defines a distal funnel end  120  terminating with a distal braid end  142 . There is a cover  124  on the proximal funnel portion  116  but not on the distal funnel portion  118 . The cover  124  may completely cover the proximal funnel portion  116 . As shown in  FIGS. 7 and 8 , the method further comprises pushing the elongate tube  102  such that the distal funnel end  120  engages the inside of the anatomical passageway  14  causing the distal portion  118  to axially bunch-up against the cover  124 , forming a ring-like structure  126  for example, and have an increased radial compression strength relative to an un-bunched configuration. The thrombus may be removed by applying suction to the lumen  110  of the elongate tube  102 , also referred to as aspiration. 
         [0029]    With reference to  FIG. 9 , the method may continue with passing a puller  400 , such as a fogarty catheter or other clot removal tools, through the lumen  110  of the elongate tube  102  and through the thrombus  18 . The puller  400  has an expandable structure on the distal end that is collapsed during this step. Next, see  FIG. 10 , the expandable structure  402  is expanded on the distal side of the thrombus  18 . The expandable structure  402  may be a balloon, or a braided structure, or other expandable structure suitable for use within an anatomical passageway. 
         [0030]    Referring to  FIG. 11 , a next step may be to use the expandable structure  402  to pull the thrombus  18  toward the braided funnel  112  and into it while applying the aforementioned suction to the lumen  110  of the elongate tube  102  and aspirate the thrombus  12 . 
         [0031]      FIG. 12  presents the funnel catheter  100  within the anatomical passageway  14  after the thrombus  402  is removed. The expandable structure  402  is subsequently collapsed and may be restrained within its own sheath depending on the type of expandable structure  402  used. 
         [0032]      FIG. 13  presents presents another step of pulling the funnel catheter  100  to retract it and bunching the braided funnel  12 . 
         [0033]      FIG. 14  presents a final step of construing the braided funnel  112  within the sheath  12  for removal from the anatomical passageway  14 . 
         [0034]    Referring again to  FIGS. 6 through 14  another method of using a funnel catheter is presented. Although shown with funnel catheter  100 , the method may be performed with other funnel catheters, for example funnel catheters  200 , or  300 . The method comprises inserting the funnel catheter  100  into an anatomical passageway  14 . As previously described, the funnel catheter  100  comprises the elongate tube  102  defining the longitudinal axis  104 , the proximal tube end  106 , the distal tube end  108 , and the lumen  110  along the longitudinal axis  104  from the proximal tube end  106  to the distal tube end  108 . The braided funnel  112  defines the interior volume  114  and has the proximal funnel portion  116  and the distal funnel portion  118 . The proximal funnel portion  116  is attached to the distal tube end  108  with the lumen  110  in fluid communication with the interior volume  114 , the proximal funnel portion  116  is funnel-shaped with a smallest diameter  134  proximate the distal tube end  108 . The distal funnel portion  118  is a cylinder that defines a constant diameter  140  along a length  144  and further defines a distal funnel end  120  terminating with a distal braid end  142 . The constant diameter  140  may be from 4 mm to 24 mm depending on the application. It is typically 1 to 2 mm greater than the vessel inside diameter. The outward flair may be 1 to 2 mm. 
         [0035]    There is a cover  124  attached to the proximal funnel portion  116 . The sheath  12 , and the braided funnel  112  and the elongate tube  102  are disposed within the sheath  12 . The proximal funnel portion  116  ends at a first plane  136  that may be transverse, for example perpendicular, to the longitudinal axis  104 . The covering  114  terminates at the first plane  136 . Where the cover  124  terminates may define the location of the first plane  136  along the longitudinal axis  104 . The distal funnel portion may terminate at a second plane  138  that may be transverse, for example perpendicular, to the longitudinal axis  104 . The method further comprises pushing the braided funnel  112  and the distal tube end  108  out of the sheath, the distal funnel end  120  engaging the inside of the distal anatomical passage  14  causing the distal funnel portion  118  to axially bunch-up against the cover  124  into a ring-like structure and have an increased radial compression strength relative to an un-bunched configuration. 
         [0036]    As shown in  FIGS. 6 and 7 , the method may comprise positioning the braided funnel  112  proximate a thrombus  18  and aspirating the thrombus  18  through the lumen  110 . In addition or alternatively, the method may comprise constraining the braided funnel  112  within the sheath  12 , as shown in  FIG. 14 . In addition or alternatively, the method may comprise withdrawing the funnel catheter  100  from the anatomical passageway  14 , typically done percutaneously. 
         [0037]    Constraining the braided funnel  12  within the sheath may be done at least two ways. The braided funnel  112  may be withdrawn into the sheath  12 , or the sheath  12  may be pushed forward over the braided funnel  112 . 
         [0038]    Various currently contemplated examples follow: 
       Example 1 
       [0039]    With reference to  FIG. 2 , an example of a funnel catheter such as funnel catheter  100  for aspirating a blockage from an anatomical passageway such as anatomical passageway  14  is provided comprising: 
         [0000]    an elongate tube such as elongate tube  102  defining a longitudinal axis such as longitudinal axis  104 , a proximal tube end such as proximate tube end  106 , a distal tube end such as distal tube end  108 , and a lumen such as lumen  110  along the longitudinal axis from the proximal tube end to the distal tube end, the proximal tube end being adapted to attach to an aspiration device such as aspiration device  10 ;
 
a braided funnel such as braided funnel  112  defining an interior volume such as interior volume  114  and having a proximal funnel portion such as proximal funnel portion  116  and a distal funnel portion such as distal funnel portion  118 , the proximal funnel portion being attached to the distal tube end with the lumen in fluid communication with the interior volume, the proximal funnel portion being funnel-shaped with a smallest diameter such as smallest diameter  134  proximate the distal tube end, the distal funnel portion defining a distal funnel end such as distal funnel end  120  terminating with a radially outward flare such as radially outward flare  122 ;
 
a cover a cover such as cover  124  on the proximal funnel portion but not on the distal funnel portion;
 
wherein the outward flare engages the inside of the anatomical passageway thereby causing the distal funnel portion  118  to axially bunch up against the cover and have an increased radial compression strength relative to an un-bunched configuration.
 
       Example 2 
       [0040]    The funnel catheter  100  of Example 1 configured wherein the distal funnel end  120  of the braided funnel  112  comprises closed braid ends  132 , as shown in  FIG. 2 . 
       Example 3 
       [0041]    The funnel catheter of Example 1 may be configured as funnel catheter such as funnel catheter  200  of  FIG. 4  wherein the distal portion of the braided funnel such as braided funnel  212  comprises open wire terminations such as open wire terminations  232 . It may also be configured as the funnel catheter such as funnel catheter of  FIG. 4  where the distal portion of the braided funnel such as braided funnel  312  comprises open wire terminations such as open wire terminations  332 . This may be implemented with the elements of Example 2 alternatively or in addition to one another. 
       Example 4 
       [0042]    As shown in  FIG. 2 , the Funnel catheter of Example 1 may be configured wherein the cover completely covers the proximal funnel portion. This applies to funnel catheter  200  of  FIG. 4  and funnel catheter  300  of  FIG. 5 , for example. This may be implemented with the elements of Examples 2 and 3, either alternatively or in addition to one another. 
       Example 5 
       [0043]    The Funnel catheter of Example 1 wherein the proximal funnel portion ends at a first plane such as first plane  136  that is transverse to the longitudinal axis, the cover terminating at the first plane. This may be implemented with the elements of Example 2, Example 3, and Example 4, either alternatively or in addition to one another. 
       Example 6 
       [0044]    The Funnel catheter of Example 1 wherein the distal funnel portion terminates at a second plane such as second plane  138  that is transverse to the longitudinal axis. This may be implemented with the elements of Example 2, Example 3, and Example 4 either alternatively or in addition to one another. 
       Example 7 
       [0045]    The Funnel catheter of claim Example 1 wherein the proximal funnel portion ends at the first plane that is transverse to the longitudinal axis, the cover terminating at the first plane, and wherein the distal funnel portion terminates at the second plane that is transverse to the longitudinal axis  104 . This may be implemented with the elements of Example 2, Example 3, and Example 4 either alternatively or in addition to one another. 
       Example 8 
       [0046]    With reference to  FIGS. 6, 7, and 8  a method of using a funnel catheter such as funnel catheter  300 ,  200 , or  100 , is provided comprising: 
         [0047]    inserting the funnel catheter into an anatomical passageway such as anatomical passageway  14 , as shown in  FIGS. 6 and 7 , the funnel catheter, comprising:
       an elongate tube such as elongate tube  102  defining a longitudinal axis such as longitudinal axis  104 , a proximal tube end such as proximal tube end  106 , a distal tube end such as distal tube end  108 , and a lumen such as lumen  110  along the longitudinal axis from the proximal tube end to the distal tube end;   a braided funnel such as braided funnel  312 ,  212 , or  112  defining an interior volume such as interior volume  114  and having a proximal funnel portion such as proximal funnel portion  116  and a such as distal funnel portion distal funnel portion  118 , the proximal funnel portion being attached to the distal tube end with the lumen in fluid communication with the interior volume, the proximal funnel portion being funnel-shaped with a smallest diameter such as smallest diameter  134  proximate the distal tube end, the distal funnel portion defining a distal funnel end such as distal funnel end  320 ,  220 , or  120  defining a distal braid end such as distal braid end  142 ;   a cover such as cover  124  on the proximal funnel portion but not on the distal funnel portion; and,       
 
         [0051]    as shown in  FIG. 8 , pushing the elongate tube such that the distal funnel end engages the inside of the distal anatomical passageway causing the distal portion to axially bunch-up against the cover and have an increased radial compression strength relative to an un-bunched configuration. 
       Example 9 
       [0052]    Example 8, the distal braid end defining a radially outward flare such as radially outward flare  122  in the embodiment of Example 12, as shown  7 . 
       Example 10 
       [0053]    Example 8, wherein the bunch-up forms a ring-like structure such as ring-like structure  126 , as shown in  FIG. 8 . This may be used with the elements of Example 9 either alternatively or in addition to one another. 
       Example 11 
       [0054]    Example 8, wherein the distal braid end of Example 12 comprises open wire terminations  332  or  232 . This may be used with the elements of Example 9 and Example 10, either alternatively or in addition to one another. 
       Example 12 
       [0055]    With reference to  FIGS. 6,7, and 8  (structure shown also shown in  FIGS. 2, 4, and 5 ) a method of using a funnel catheter such as funnel catheter  300 ,  200 , or  100  is provided, comprising: 
         [0056]    inserting the funnel catheter into an anatomical passage way such as anatomical passageway  14 , the funnel catheter comprising:
       an elongate tube such as elongate tube  102  defining a longitudinal axis such as longitudinal axis  104 , a proximal tube end such as proximal tube end  106 , a distal tube end such as distal tube end  108 , and a lumen such as lumen  110  along the longitudinal axis from the proximal tube end to the distal tube end;   a braided funnel such as braided funnel  312 ,  212 , or  112  defining an interior volume such as interior volume  114  and having a proximal funnel portion such as proximal funnel portion  116  and a distal funnel portion such as distal funnel portion  118 , the proximal funnel portion being attached to the distal tube end with the lumen in fluid communication with the interior volume, the proximal funnel portion being funnel-shaped with a smallest diameter such as smallest diameter  134  proximate the distal tube end, the distal funnel portion defining a distal funnel end such as distal funnel end  320 ,  220 , or  120  terminating with a distal braid end such as distal braid end  142 ;   a cover such as cover  124  on the proximal funnel portion and attached thereto; and,   a sheath such as sheath  12 , the braided funnel and the elongate tube disposed within the sheath;   wherein the proximal funnel portion ends at a first plane that is transverse to the longitudinal axis, the cover terminating at a first plane such as first plane  137 , and wherein the distal funnel portion terminates at a second plane such as second plane  138  that is transverse to the longitudinal axis; and,       
 
         [0062]    pushing the braided funnel and the distal tube end out of the sheath, the distal funnel end engaging the inside of the anatomical passage causing the distal funnel portion to axially bunch-up against the cover into a ring-like structure such as ring-like structure  126  and have an increased radial compression strength relative to an un-bunched configuration. 
       Example 13 
       [0063]    Example 12 the distal funnel end defining a radially outward flare such as radially outward flare  122  as shown in  FIG. 7  (structure also shown in  FIGS. 2 and 4 ). 
       Example 14 
       [0064]    Example 12 wherein the distal portion of the braided funnel comprises closed braid ends such as closed braid ends  132  as shown in  FIG. 7  (structure also shown in  FIG. 2 ). The elements of this Example 14 may be used with the elements of Example 13, either alternatively or in addition to one another. 
       Example 15 
       [0065]    Example 12 wherein the distal funnel end of the braided funnel comprises open wire terminations such as open wire terminations  332  or  232  (structure shown in  FIGS. 4 and 5 ). This may be used with the elements of Example 13, either alternatively or in addition to one another. 
       Example 16 
       [0066]    Example 12 wherein the proximal funnel portion has an outer surface and the cover completely covers the outer surface as shown in  FIG. 7  (structure also shown in  FIGS. 2, 4, and 5 ). This may be used with the elements of Example 13, Example 14, and Example 15, either alternatively or in addition to one another. 
       Example 17 
       [0067]    Example 12 comprising positioning the braided funnel proximate a thrombus such as thrombus  18 , as shown in  FIGS. 6 through 10 , and aspirating the thrombus through the lumen  110 , as shown in  FIGS. 11 and 12 . This may be used with the elements of Example 13, Example 14, Example 15, and Example 16, either in alternatively or in addition to one another. 
       Example 18 
       [0068]    Example 12 comprising constraining the braided funnel and the distal tube within the sheath. This may be used with the elements of Example 13, Example 14, Example 15, Example 16, and Example 17, either alternatively or in addition to one another. 
       Example 19 
       [0069]    Example 12 comprising withdrawing the funnel catheter from the anatomical passageway. This may be used with the elements of Example 13, Example 14, Example 15, Example 16, Example 17 and Example 18 either alternatively or in addition to one another. 
       Example 20 
       [0070]    Example 12 comprising: 
         [0071]    positioning the funnel proximate a thrombus and aspirating the thrombus through the lumen, as shown in  FIGS. 6 through 12 ; 
         [0072]    constraining the braided funnel within the sheath, as shown in  FIG. 14 ; and, 
         [0073]    withdrawing the Funnel catheter from the anatomical passageway. 
         [0074]    All features and modifications of the described examples and dependent claims are usable in all aspects of the examples taught herein. Furthermore, the individual features of the dependent claims, as well as all features and modifications of the described examples are combinable and interchangeable with one another.