Patent Publication Number: US-2020297988-A1

Title: Surgical tool positioning device

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims the benefit of and priority to U.S. Provisional Patent Application No. 62/819,699 filed Mar. 18, 2019, the entire disclosure of which is incorporated by reference herein. 
    
    
     BACKGROUND 
     1. Technical Description 
     The disclosure is directed to a device and method for positioning a surgical tool within a body lumen and, more particularly, to a device and method for positioning an endoscope within a body lumen. 
     2. Background of Related Art 
     Endoscopes are routinely inserted into body vessels to allow a surgeon to visualize the interior of the body vessel for diagnostic purposes and/or to treat tissue. In some surgical procedures, it is necessary to access a body vessel through a natural body orifice. These procedures, also known as natural orifice transluminal endoscopic surgeries, sometimes require advancement of an endoscope deep into the body vessel. In these procedures, advancement may be impeded by the curvature of the body vessel. 
     A continuing need exists in the art for an endoscope positioning device that is capable of allowing an endoscope to traverse deep into a lumen defined by the body vessel without damaging the body vessel. 
     SUMMARY 
     One aspect of the disclosure is directed to a positioning device for accessing target tissue within a body lumen with a surgical device. The positioning device includes a housing, a sleeve, and a source of pressurized fluid. The housing defines a central bore and a pressure chamber and includes a delivery side and a return side. The sleeve has a first end and a second end and an inverted distal portion located between the first and second ends. The first end of the sleeve is supported on the delivery side of the housing and the second end of the sleeve supported on the return side of the housing. The inverted distal portion defines a cavity and a central guide channel. The cavity is in communication with the pressure chamber of the housing. The source of pressurized fluid communicates with the pressure chamber of the housing, wherein when pressurized fluid is directed into the pressure chamber, the pressurized fluid enters the cavity of the inverted distal portion of the sleeve to advance the inverted distal portion of the sleeve away from the housing. 
     In embodiments, an annular support mechanism is supported on the housing and the sleeve is wound about the annular support mechanism. 
     In some embodiments, the annular support mechanism is supported on the delivery side of the housing. 
     In certain embodiments, the annular support mechanism is supported on the return side of the housing. 
     In embodiments, the annular support mechanism includes a motor driven toroid. 
     In embodiments, the annular support mechanism includes a rotatable toroid. 
     In some embodiments, a first clamp is supported on the housing adjacent the annular support mechanism, the first clamp movable from an unclamped position to a clamped position to control an advancement rate of the distal inverted portion of the sleeve. 
     In certain embodiments, a first actuator is coupled to the first clamp, and the first actuator is actuatable to selectively move the first clamp between an unclamped position and a clamped position. 
     In embodiments, a first flexible sealing member is positioned about the central bore of the housing to engage the sleeve and prevent fluid from passing between the flexible sealing member and the sleeve. 
     In embodiments, a second flexible sealing member is positioned on the housing to engage an inner surface of an outer portion of the sleeve to prevent fluid from passing between the sleeve and the housing. 
     In some embodiments, the flexible sealing member has a tear-drop shaped cross-section. 
     In certain embodiments, the flexible sealing member includes a duck-bill valve. 
     In certain embodiments, a fluid control valve includes an inlet that communicates with the source of pressurized fluid and an outlet that communicates with the pressure chamber in the housing. 
     In embodiments, the inlet to the fluid control valve also communicates with a vent. 
     In some embodiments, a surgical device has a flange and is supported within the guide channel, wherein the flange is positioned distal of the inverted distal portion of the sleeve such that advancement of the sleeve away from the housing moves the surgical device away from the housing. 
     In certain embodiments, the guide channel on the return side of the housing is open to receive a surgical device. 
     In embodiments, the sleeve is formed of an aromatic polyamide such as Kevlar®. Alternately, other materials of construction are envisioned including cloth, nylon, polyester, polyethylene, woven fabrics, composites, or the like. 
     Another aspect of the disclosure is directed to a delivery device for positioning a surgical device adjacent target tissue within a body lumen. The delivery device includes a housing, a sleeve, a source of pressurized fluid, and a surgical device. The housing defines a central bore and a pressure chamber that communicates with the central bore, and includes a delivery side and a return side. The sleeve has a first end and a second end and an inverted distal portion located between the first and second ends. The first end of the sleeve is supported on the delivery side of the housing and second end of the sleeve is supported on the return side of the housing. The inverted distal portion defines a cavity and a central guide channel. The cavity is in communication with the pressure chamber. The source of pressurized fluid communicates with the pressure chamber of the housing. The surgical device extends through the guide channel and includes a body having a flange that is positioned distally of the inverted distal portion of the sleeve. When pressurized fluid is directed to the pressure chamber, the pressurized fluid is directed into the cavity of the inverted distal portion of the sleeve to advance the inverted distal portion of the sleeve and the surgical device away from the housing. 
     In embodiments, the surgical device is an endoscope. 
     In some embodiments, the delivery device includes an annular support mechanism and a first clamp. The annular support mechanism includes a rotatable toroid supported on the housing. The sleeve is wound about rotatable toroid. The first clamp is supported on the housing adjacent the annular support mechanism and is movable from an unclamped position to a clamped position to control an advancement rate of the distal inverted portion of the sleeve. 
     Another aspect of the disclosure is directed to a method of positioning a surgical device adjacent target tissue within a lumen of a body vessel. The method includes securing a first end of a tubular sleeve to a delivery side of a housing; inverting the sleeve within the housing and positioning a second end of the sleeve on a return side of the housing such that the sleeve defines a central guide channel and the inverted distal portion of the sleeve defines a cavity; and coupling the cavity defined by the inverted distal portion of the sleeve with a pressure chamber in the housing to facilitate advancement of the inverted distal portion of the sleeve away from the housing through a lumen of a body vessel. 
     In embodiments, the method includes controlling the advancement rate of the inverted distal portion of the sleeve. 
     In some embodiments, controlling the advancement rate of the inverted distal portion of the sleeve includes actuating a first clamp to clamp and unclamp the sleeve. 
     In certain embodiments, delivering pressurized fluid to the cavity includes advancing the distal inverted portion of the sleeve within the lumen of the body vessel to a point midway between the housing and the target tissue. 
     In embodiments, the method further includes positioning a surgical device within the guide channel such that the surgical device is frictionally retained within the guide channel, and advancing the distal inverted portion to the target tissue with the surgical device supported on the sleeve. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Various embodiments of the disclosed positioning device for a surgical device are described herein below with reference to the drawings, wherein: 
         FIG. 1  is a side perspective view of an exemplary embodiment of the disclosed surgical device positioning device supporting an endoscope with an elongate sleeve of the positioning device extending from a return side of a housing of the device; 
         FIG. 2  is a side cross-sectional view of the endoscope positioning device shown in  FIG. 1  with the endoscope positioned within an entry opening of a natural body orifice and the sleeve of the positioning device in a retracted position within a body lumen; 
         FIG. 2A  is a side perspective view of a portion of a drive member of a winding mechanism of the positioning device shown in  FIG. 1 ; 
         FIG. 2B  is a side perspective view of the drive member of the winding mechanism of the positioning device shown in  FIG. 1 ; 
         FIG. 2C  is a side view of a braking device of the positioning device shown in  FIG. 1  engaged with the sleeve with the sleeve supported on the drive member; 
         FIG. 3  is a side cross-sectional view of the positioning device shown in  FIG. 2  with the sleeve extending through the natural body orifice to a position within the body vessel with the endoscope supported on the sleeve; 
         FIG. 4  is a side cross-sectional view of the positioning device shown in  FIG. 3  with the sleeve and the endoscope advanced further into the body vessel; and 
         FIG. 5  is a side cross-sectional view of the positioning device shown in  FIG. 2  with the endoscope advanced further into the body vessel; 
         FIG. 6  is a side cross-sectional view of another exemplary embodiment of the disclosed positioning device with the elongate sleeve positioned within an entry opening of a natural body orifice; 
         FIG. 6A  is a side schematic view of the positioning device shown in  FIG. 6  as the sleeve in inserted into vasculature in a brain of a patient; 
         FIG. 6B  is a front perspective view of a seal member of the positioning device shown in  FIG. 6 ; 
         FIG. 7  is a side schematic view of the positioning device with the elongate sleeve positioned through a natural body orifice into a body vessel and extended about halfway to target tissue; 
         FIG. 8  is a side schematic view of the positioning device shown in  FIG. 8  as an endoscope is introduced into a proximal end of the elongate sleeve; 
         FIG. 9  is a side schematic view of the positioning device shown in  FIG. 9  with the endoscope and the elongate sleeve advanced to the target tissue; and 
         FIG. 10  is a flowchart illustrating one exemplary method for positioning a surgical device adjacent target tissue within a lumen of a body vessel using the positioning device shown in  FIG. 6 . 
     
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS 
     The disclosed positioning device will now be described in detail with reference to the drawings in which like reference numerals designate identical or corresponding elements in each of the several views. However, it is to be understood that the disclosed embodiments are merely exemplary of the disclosure and may be embodied in various forms. Well-known functions or constructions are not described in detail to avoid obscuring the disclosure in unnecessary detail. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the disclosure in virtually any appropriately detailed structure. 
     In this description, the term “proximal” is used generally to refer to that portion of the device that is closer to a clinician, while the term “distal” is used generally to refer to that portion of the device that is farther from the clinician. In addition, the term “endoscopic” is used generally used to refer to endoscopic, laparoscopic, arthroscopic, and/or any other procedure conducted through small diameter incision or cannula. Further, the term “clinician” is used generally to refer to medical personnel including doctors, nurses, and support personnel. 
     Referring to  FIGS. 1 and 2 , the disclosed positioning device is shown generally as positioning device  10  and includes a housing  12 , an elongated tubular sleeve  14 , a first actuator  16 , first clamps  18 , a second actuator  20 , second clamps  24  ( FIG. 2 ), and a fluid control valve  26 . A surgical device, e.g., an endoscope  28 , is supported on a distal portion  30  ( FIG. 2 ) of the sleeve  14  and is movable with the sleeve  14  within a lumen “L” defined by a body vessel “By” ( FIG. 2 ) as described in detail below. 
       FIG. 2  illustrates the surgical device, e.g., the endoscope  28 , supported on a distal inverted portion  30  of the elongate sleeve  14  as the endoscope  28  and the sleeve  14  are introduced through a natural body orifice into the lumen “L” of the body vessel “By”. The endoscope  28  is positioned within the sleeve  14  and includes a body  28   a  and an annular support flange  34  that extends transversely from the body  28   a  to a position distally of the distal portion  30  of the sleeve  14 . When the sleeve  14  is advanced from the housing  12 , the support flange  34  is positioned to be engaged by the distal inverted portion  30  of the sleeve  14  to advance the endoscope  28  within the lumen “L”. 
     In embodiments, the endoscope  28  includes an elongate flexible body  36  and a visualization device  38  that is supported on a distal portion of the flexible body  36 . The flexible body  36  may define one or more channels  44  for receiving a surgical device such as a dissector, a grasper, a biopsy device, for treating tissue or the like. For example, a surgical device may be extendable through the endoscope  28  to remove polyps “P” ( FIG. 2 ) from within the body vessel “By” during a colonoscopy procedure. In some embodiments, the distal portion of the flexible body  36  of the endoscope  28  may include a series of interconnected links  42  that are pivotally coupled together, e.g., via universal joints, to control positioning of the distal portion of the endoscope  28  within the body vessel “By”. 
     The housing  12  of the positioning device  10  defines a longitudinal axis “X” and a central bore  46  that is coaxial with longitudinal axis “X”. The housing  12  includes a delivery side  51  from which the distal inverted portion  30  extends, and a return side  53  from which the second end of the sleeve  14  extends. The first and second actuators  16  and  20  are supported on the housing  12  and are coupled to the first clamps  18  and the second clamps  24 , respectively. The first actuator  16  is operable to move the first clamps  18  from a first unclamped position ( FIG. 3 ) to a second clamped position ( FIG. 4 ). Similarly, the second actuator  20  is operable to move the second clamps  24  from a first unclamped position ( FIG. 3 ) to a second clamped position ( FIG. 5 ). The first and second actuators  16  and  20  can be actuated independently of each other to control delivery and winding of the elongate sleeve  14  as described below. 
     The sleeve  14  extends through the central bore  46  of the housing  12  and has a first end  50  that is mounted to the delivery side  51  of the housing  12 . The sleeve  14  is inverted such that the second end  52  of the sleeve  14  extends through the central bore  46  of the housing  12  from the return side  53  of the housing  12 . The inverted distal portion  30  of the sleeve  14  defines a central channel  56  that extends between the first and second ends  50  and  52  of the sleeve  14 . The second end of the sleeve  14  is open to allow the surgical device, e.g., the endoscope  28 , to be fed into the central bore  56 . 
     In embodiments, the delivery side of the housing  12  includes an annular sleeve support mechanism  60  for supporting and rolling the sleeve  14 .  FIGS. 2-2C  illustrate the annular sleeve support mechanism  60  which includes toroid  62  including a flexible annular support ring  64  and one or more rollers  65  supported on the ring  64  for rotation. The first end  50  ( FIG. 2C ) of the sleeve  14  is wound about the toroid  62  in a manner to allow the sleeve  14  to be selectively rolled about the toroid  62  or dispensed from the toroid  62  to deliver the sleeve  14  into the body vessel “By” ( FIG. 2 ) or to withdraw the sleeve  14  from within the body vessel “By”. 
     In embodiments, an electric motor driven wheel  63  ( FIG. 2C ) or the like is positioned adjacent to the toroid  62  to engage the sleeve  14 . The electric motor driven wheel  63  is operable to wind or unwind the sleeve  14  about the toroid  62 . A biasing member  67  ( FIG. 2C ) may be provided to urge the wheel  63  into engagement with the sleeve  14 . Non-driven guide wheels  69  may also be provided to ensure that the sleeve  14  remains in tension as the sleeve  14  is wound about the toroid  62 . 
     It is contemplated that a variety of different types of drive members can be used to wind the sleeve  14  about the toroid  62 . For example, an electric motor can be coupled directly to the ring  64  to rotate the ring  64  to wind and unwind the sleeve  14  about the toroid  62 . 
       FIGS. 3-5  illustrate the delivery device  10  as the sleeve  14  is advanced through the lumen “L” of the body vessel “By”. The delivery device  10  includes an annular, flexible sealing member  66  to provide a seal about the inverted portion  30  of the sleeve  14  and the endoscope  28 . In embodiments, the sealing member  66  is supported within an annular recess  68  defined within the housing  12  of the positioning device  10  and has a tear-drop shaped cross-sectional configuration. Alternately, other sealing member configurations are envisioned. For example, the sealing member  66  may also be in the form of a duck-bill valve  66 ′ ( FIG. 6B ) which is discussed in further detail below. The sealing member  66  is formed of a flexible material, e.g., rubber, and is positioned to engage an outer surface of the sleeve  14  to prevent fluid, e.g., air, from passing between the sleeve  14  and the housing  12  through the proximal end of the central opening  46 . 
     In some embodiments, an additional sealing member  66   a  is provided to engage an internal surface of an outer portion  30   a  ( FIG. 2  in phantom) of the sleeve  14  to provide a seal between the inner surface of the sleeve  14  and the housing  12  of the positioning device  12  adjacent the sleeve support mechanism  60 . 
     The housing  12  defines a pressure chamber  70  that communicates with the fluid control valve  26  via a conduit  74 . The fluid control valve  26  has an inlet  72  that communicates with a source of pressurized fluid  76  and an outlet  74   a  ( FIG. 2 ) that communicates with the conduit  74 . In some embodiments, the inlet  72  can also communicate with a vent  78  that can vent the pressure chamber  70  if necessary. 
     As described above, the sleeve  14  is tubular and has its first end  50  wound about the toroid  62  and a second end  52  that extends through the central bore  46  and to the return side of the housing  12 . The distal inverted portion  30  of the sleeve  14  defines an enclosed cavity  80  with the flexible sealing member  66  that communicates with the pressure chamber  70  of the housing  12 . When the fluid control valve  26  is actuated to pressurize the chamber  70  in the housing  12 , the cavity  80  defined by the sleeve  14  is pressurized such that a force is applied to the distal inverted portion  30  of the sleeve  14 . This force on the inverted distal portion  30  of the sleeve  14  urges the sleeve  14  to unfurl from about the toroid  62  and extend outwardly of the housing  12  into the lumen “L” of the body cavity “By”. The first and second clamps  18 , and  24  are moved between clamped and unclamped positions to control delivery (or withdrawal of) the sleeve  14 . 
     As discussed above, the housing  12  supports the first actuator  16  and the first clamps  18  on the delivery side  51  of the housing  12 . The first actuator  16  is coupled to the first clamps  18  such that the first clamps  18  can be selectively moved from an unclamped position ( FIG. 3 ) spaced from the sleeve  14  on the toroid  62  to allow unfurling of the sleeve  14  from the toroid  62  to a clamped position ( FIG. 4 ) engaged with a portion of the sleeve  14  that is wound about the toroid  62  to prevent unfurling of the sleeve  14  from the toroid  62 . 
     The housing  12  also supports the second actuator  20  and the second clamp  24  on the return side of the housing  12 . The second actuator  20  is coupled to the second clamps  24  such that the second clamps  24  can be selectively moved from an unclamped position ( FIG. 3 ) spaced from the sleeve  14  to allow the sleeve  14  to move through the central opening  46  of the housing  12  from the return side  53  of the housing  12  to the delivery side  51  of the housing  12  to a clamped position engaged with the sleeve  14  to prevent the sleeve  14  being fed through the housing  12 . In embodiments, the first clamps  18  are spaced about the delivery side  51  of the housing  12  adjacent to the toroid  62  and the second clamp  24  includes one or more clamping members  24  spaced about the central opening  46  adjacent the return side of the housing  12 . 
     In use, the distal inverted portion  30  of the sleeve  14  is positioned within the lumen “L” of a body vessel “BV”. When the fluid control valve  26  is actuated to direct pressurized fluid in the direction indicated by arrows “A” into the pressure chamber  70  of the housing  12  and the first clamps  18  are in the unclamped positions, the fluid pressure moves into the cavity  80  in the distal inverted portion  30  of the sleeve  14  in the direction indicated by the arrow “B”. When the pressurized fluid enters the cavity  80  in the distal inverted portion  30  of the sleeve  14 , the sleeve  14  is forced distally within the lumen “L” of the body vessel “By” and unfurls from about the toroid  62  (or is pulled through the central opening  46  of the housing  12 ) such that the distal portion  30  of the sleeve  14  extends into the lumen “L” defined by the body cavity “BC” in a substantially linear direction. Although the second clamps  24  are shown unclamped in  FIG. 3 , it is noted that the second clamps  24  can be clamped such that the sleeve  14  is fed into the lumen “L” of the body cavity “By” on from about the toroid  62 . 
     As illustrated in  FIG. 4 , the first clamps  18  can be selectively actuated to control the rate at which the sleeve is unfurled from the toroid  62 . Similarly, as illustrated in  FIG. 5 , the second clamp  24  can be actuated to control the rate at which the sleeve  12  is fed through the central opening  46  of the housing  12 . The flexibility of the sleeve  14  allows the sleeve  14  to follow the path defined by the body vessel “By” as the sleeve  12  translates through the lumen “L” of the body vessel “By”. 
     The disclosed positioning device  10  is particularly suited for transporting a surgical device, e.g., an endoscope  28 , deep within a body vessel “By” during a surgical procedure such as during a colonoscopy. It is envisioned that during such a procedure, the surgical device  40  can be advanced from within the endoscope  28  to treat tissue. For example, the positioning device  10  can be advanced through the lumen “L” of the body vessel “By” to a position adjacent a polyp “P” ( FIG. 5 ) which can be identified with the visualization device  38  of the endoscope  28 . When the endoscope  28  is properly positioned within the lumen “L” of the body vessel “By”, the surgical device  40  can be actuated to remove the polyp “P”. After the surgical procedure is completed, the fluid control valve  26  can be actuated to vent the cavity  80  in the distal portion  30  of the sleeve  14  and the sleeve  14  can be retracted about the toroid  62  to withdraw the endoscope  28  from the lumen of the body vessel “By”. 
     It is also contemplated that the size of the positioning device  10  can be miniaturized to facilitate entry of the sleeve  14  into very small body vessels such as described below in regard to  FIG. 6A . 
     Although not shown, the positioning device  10  need not include a second actuator  20  and second clamps  24 . In addition, a support mechanism including a second toroid can be provided on the return side  53  of the housing  12  to provide to wind the sleeve  14  extending from to the return side  53  of the housing  12  such that the sleeve  12  on the return side  53  of the housing  12  can be selectively unfurled by operating the second actuator  20  and second clamps  24 . 
       FIG. 6  illustrates an alternate embodiment of the disclosed positioning device shown generally as positioning device  100 . The positioning device  100  is substantially similar to the positioning device  10  except that a first end  102  of the sleeve  114  is fixedly secured to the delivery side  151  of the housing  112 , the annular sleeve support mechanism  160  including the toroid  162  is supported on the return side  153  of the housing  112  of the positioning device  100  and supports the second end  104  of the sleeve  114 , and the first actuator  16  ( FIG. 2 ) and first clamps  18  are eliminated. The housing  112  defines a pressure chamber  170  that communicates with the fluid control valve  126  via a conduit  174 . The fluid control valve  126  has an inlet  172  that communicates with a source of pressurized air  176  and an outlet  174   a  that communicates with the conduit  174 . In some embodiments, the inlet  172  may also communicate with a vent  178  that can vent the pressure chamber  170  if necessary. 
     The positioning device  100  includes an actuator  120  ( FIG. 6 ) which is operable to move the clamps  124  from a first unclamped position to a second clamped position to control delivery of the sleeve  114  from about the toroid  162 . The actuator  120  and clamps  124  operate in a manner that is substantially the same as the actuator  20  ( FIG. 2 ) and the second clamps  24  and are not described in further detail herein. 
     In embodiments, the positioning device  100  can be used to provide a pathway  156  to target tissue within a lumen “L” of a body vessel “BV” and is not used to deliver the surgical device “Z” ( FIG. 8 ) to the target tissue “P”. As such, the sleeve  114  is advanced to the target tissue “A” independently of the surgical device, e.g., an endoscope. More specifically, the positioning device  100  is used to extend the sleeve  114  through a lumen “L” of a body vessel “By” to provide a guide path  156  through the inverted portion  130  ( FIG. 6 ) of the sleeve  114  to the target tissue “P”. The sleeve  114  can be formed of a material that is durable to protect an inner wall of the body vessel “By” during positioning of the surgical device through the guide path  156 . After the sleeve  114  is advanced to the target tissue “P”, the surgical device “Z” can be pushed through the guide path  156  within the body vessel “By” to access the target tissue “A”. 
     In embodiments, the sleeve  114  is formed of Kevlar or a similar material to protect the inner wall of the body vessel “By” and to guide the surgical device “Z” ( FIG. 8 ) to the target tissue “A”. Alternately, the sleeve  114  can be formed of a variety of different materials including, but not limited to, cloth, nylon, polyester, composites or the like. In some embodiments, the sleeve  114  is formed of a woven fabric that includes plastic fibers, e.g., polyethylene, that give the material a fluid tight (air, saline, water) structure. In other embodiments, the sleeve  114  is formed of composite fiber reinforced plastic, where the plastic provides sealing and the fibers provide the material with a high tensile strength. 
     As discussed above, the sealing member  66 ′ may be in the form of a duckbill valve ( FIG. 6B ) that is normally closed and seals the guide path  156  until a surgical device “Z” is introduced into the guide path  156 . Alternately, other types of sealing members can be used to provide a seal about the inverted portion  130  of the sleeve  114  when a surgical device is not present within the guide path  156 . 
     The sleeve  100  can be formed of a very thin material to facilitate delivery of the sleeve  14  through body lumens having very small diameters. For example,  FIG. 6A  illustrates the positioning device  100  during delivery of the sleeve  114  into blood vessels in the brain of a patient to treat an aneurysm “A”. In such a procedure, the sleeve  114  is introduced into the blood vessel “By” through an incision “I” in the head. The pressure chamber  170  ( FIG. 6 ) is pressurized by opening the fluid control valve  126 . As discussed above in regard to positioning device  10 , the pressure chamber  170  of positioning device  100  communicates with the cavity  180  ( FIG. 6 ) defined by the sleeve  114  such that the pressure within the cavity  180  forces the distal inverted portion  130  of the sleeve  114  through the blood vessel “BV” to the site of the target tissue “A”. After the sleeve  114  is advanced to the site of the target tissue “A”, the surgical device “Z” which may include a variety of different tool types can be inserted through the guide channel  156  ( FIG. 6 ) defined by the sleeve  114  to the target tissue “A”. 
       FIGS. 7-10  illustrate an alternate method for delivering a surgical device “Z” to target tissue “A” within a body vessel “By”. In this method, illustrated in a flowchart shown in  FIG. 10 , the first end of the sleeve  114  is secured to a delivery side  151  of the housing  112  (see  202 ,  FIG. 10 ), a distal portion of the sleeve  114  is inverted within the housing  112  and a second end of the sleeve  114  is positioned on a return side  153  of the housing  112  such that the sleeve  112  defines a central guide channel  156  and the inverted distal portion of the sleeve  114  defines a cavity  180  (see  204 ,  FIG. 10 ), and the cavity  180  is coupled to a pressure chamber in the housing  112  to facilitate advancement of the inverted distal portion of the sleeve  114  from the housing through a lumen “L” of a body vessel “By” (see  206 ,  FIG. 10 ). 
     After the sleeve  114  is coupled to the housing  112 , the sleeve  114  is advanced within the body vessel “By”. Advancement of the sleeve  114  is controlled with the clamps  124  as described above ( 208 ,  FIG. 10 ). In embodiments, the sleeve  114  is advanced in the manner described above to a position “M” about midway to the target tissue “A” ( FIG. 7 ) ( 210 ,  FIG. 10 ). After the distal portion  130  of the sleeve  114  is positioned within the body vessel “By” about midway to the target tissue “A”, the surgical device “Z” is introduced into the sleeve  114  from the return side  153  of the housing  112  such that the surgical device “Z” is frictionally retained in the guide path  156  by engagement with the sleeve  114  ( FIG. 8 ) ( 212 ,  FIG. 10 ). Once the surgical device “Z” is supported within the sleeve  114 , the sleeve  114  is advanced to the target tissue to advance the surgical device “Z” to the target tissue “A”  FIG. 9 ) ( 214 ,  FIG. 10 ). Since the sleeve  114  is inverted, the surgical device “Z” will be advanced to the target tissue “A” at twice the rate that the distal portion  130  of the sleeve  114  advances to the surgical device “Z”. As such, the surgical device Z will reach the target tissue “A” at about the same time that the distal inverted portion  130  of the sleeve  114  reaches the target tissue “A”. 
     Although the disclosure is directed to a positioning device  10 ,  100  for positioning and/or delivering an endoscope, to a location within a lumen of a body vessel, it is envisioned that the positioning device  10 ,  100  may be used to position and/or deliver a variety of different types of surgical devices into a lumen of a body vessel including staplers, dissectors, ultrasonic devices, graspers, clip appliers, etc. It is also noted that although the disclosure discloses the use of first and second clamps, it is envisioned that one or more clamps can be provided to selectively control advancement of the positioning device and/or the surgical device within a lumen of a body vessel. 
     Persons skilled in the art will understand that the devices and methods specifically described herein and illustrated in the accompanying drawings are non-limiting exemplary embodiments. It is envisioned that the elements and features illustrated or described in connection with one exemplary embodiment may be combined with the elements and features of another without departing from the scope of the disclosure. As well, one skilled in the art will appreciate further features and advantages of the disclosure based on the above-described embodiments. Accordingly, the disclosure is not to be limited by what has been particularly shown and described, except as indicated by the appended claims.