Abstract:
A torque-transmitting, variably-flexible, locking insertion device includes a hollow body having a proximal end with an entrance for receiving an instrument, a distal end with a tip for protrusion of the instrument, and a handle to be gripped by an operator. A device locks the handle to and unlocks the handle from the instrument, which is at least partly disposed within the hollow body. A device transitions the hollow body between a relatively flexible condition and a relatively stiff condition. A method for operating a torque-transmitting, locking insertion device includes placing the instrument at least partly within the hollow body and locking the handle to and unlocking the handle from the instrument. The hollow body is transitioned between a relatively flexible condition and a relatively stiff condition.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The invention relates to a torque-transmitting, variably-flexible, locking insertion device. The invention also relates to a method for operating the insertion device. 
         [0003]    2. Description of the Related Art 
         [0004]    Prior art insertion devices of this general type cannot be connected to an instrument, such as an endoscope or a colonoscope, in such a manner as to be reliable and sufficiently torque-transmitting, while at the same time being easily releasable therefrom and variably flexible. The operator of the device must have the ability to manipulate the instrument when necessary with the insertion device and yet free the instrument easily when necessary. 
         [0005]    Devices produced by Spirus Medical, Inc. under the designations Endo-Ease advantage, Endo-Ease discovery and Endo-Ease vista are lightly engaged to and disengaged from a colonoscope and rotate independently thereof. The devices have a spiral at the distal end to follow the lumen of the colon or small bowel when rotated and pushed forward. All three devices have a fixed and predetermined greater flexibility at the distal end and lesser flexibility at the proximal end. 
       SUMMARY OF THE INVENTION 
       [0006]    It is accordingly an object of the invention to provide a torque-transmitting, variably-flexible, locking insertion device and a method for operating the insertion device, which overcome the hereinafore-mentioned disadvantages of the heretofore-known devices and methods of this general type and which permit an operator of the device to easily and reliably lock the insertion device to and unlock the insertion device from an instrument while varying stiffness. 
         [0007]    With the foregoing and other objects in view there is provided, in accordance with the invention, a torque-transmitting, locking insertion device. The insertion device comprises a hollow body having a proximal end with an entrance for receiving an instrument, such as a scope, a distal end with a tip for protrusion of the instrument, and a handle to be gripped by an operator. A device locks the handle to and unlocks the handle from the instrument, which is at least partly disposed within the hollow body. A device, which may be vacuum activated, transitions the hollow body between a relatively flexible condition and a relatively stiff condition. 
         [0008]    With the objects of the invention in view, there is also provided a method for operating a torque-transmitting, locking insertion device. The method comprises providing a hollow body having a proximal end with an entrance for receiving an instrument, such as a scope, a distal end with a tip for protrusion of the instrument, and a handle to be gripped by an operator. The instrument is placed at least partly within the hollow body and the handle is locked to and unlocked from the instrument. The hollow body is transitioned between a relatively flexible condition and a relatively stiff condition, such as by vacuum activation. 
         [0009]    Thus, through the use of the invention, an operator of the insertion device can not only lock the device to and unlock the device from an instrument, but can also transition the device between relatively flexible and relatively stiff conditions, while applying torque and axial movement to the instrument. 
         [0010]    In accordance with another feature of the invention, the locking and unlocking device includes an actuator to be activated by the operator for locking the handle to and unlocking the handle from the instrument. The actuator may be a bobbin to be slid onto the handle by the operator. The locking and unlocking device may also include a clamping plate disposed within the actuator. The clamping plate is moved radially inwardly against the instrument and radially outwardly away from the instrument by activating the actuator. This structure provides a simple and easy to use locking device, which nevertheless delivers reliable locking of an instrument while transmitting torque and advancing axially. 
         [0011]    In accordance with a further feature of the invention, the clamping plate includes a plurality of partial-plates, at least one spring biasing the partial-plates radially outwardly and detents integral with the partial-plates. The detents are disposed in recesses in the actuator in a non-actuated condition and slide out of the recesses and push the partial-plates towards the instrument against a force of the at least one spring into an actuated condition. A body tube is disposed partially within the actuator and partially within the handle. The body tube has slots formed therein within which the detents slide between the actuated and non-actuated conditions. The handle has a collar limiting motion of the actuator into the actuated condition. Although the plates, detents and springs are simple elements, they produce reliable locking between the handle and the bobbin. 
         [0012]    In accordance with an added feature of the invention, a corrugated tube transmits torque from the proximal end toward the distal end. An inner sleeve disposed within the corrugated tube prevents vacuum leakage and aids in insertion of the instrument. Tendons are disposed along the corrugated tube within the hollow body for maintaining the hollow body in the relatively flexible and relatively stiff conditions. 
         [0013]    In accordance with an additional feature of the invention, the hollow body has an outer jacket, the tendons are at least partly disposed between the outer jacket and the corrugated tube, and the transitioning device applies suction between the outer jacket and the corrugated tube for frictionally locking the tendons in place. The corrugated tube provides a certain inherent stiffness, which can be greatly increased by the operator of the insertion device by locking the tendons between the outer jacket and the corrugated tube. 
         [0014]    In accordance with yet another feature of the invention, a coupler disposed within the handle defines a vacuum plenum volume therebetween. The handle has a vacuum inlet/outlet hole formed therein communicating with the vacuum plenum volume. 
         [0015]    In accordance with yet a further feature of the invention, a sliding valve encircles the handle and has a vacuum inlet/outlet formed therein for communicating with the vacuum connection. The sliding valve slides between a position in which the vacuum inlet/outlet communicates with the vacuum inlet/outlet hole and a position in which the vacuum inlet/outlet is sealed against the vacuum inlet/outlet hole. Thus, the variation in stiffness is provided by simply applying and releasing vacuum when desired by the operator. 
         [0016]    In accordance with a concomitant feature of the invention, vertebrae are disposed along the corrugated tube, between corrugation peaks, for guiding the tendons. The vertebrae include at least one last vertebra closest to the distal end. Each two of the tendons form legs of a U-shaped configuration passing through holes in the vertebrae and being interconnected by a crosspiece distally of the last vertebra. There may be two last vertebrae between which the crosspiece is fixed. The tendons may vary in number along the hollow body for providing zones of varying stiffness. The tendons float when the hollow body is in the relatively flexible condition. The tendons are not in tension or compression when the hollow body is in the relatively stiff condition. The tendons are not under tension in both the relatively flexible and relatively stiff conditions. The combination of the vertebrae and the tendons provide inherent stiffness to the degree desired, while permitting added stiffness to be attained by the transitioning device. 
         [0017]    Other features which are considered as characteristic for the invention are set forth in the appended claims. 
         [0018]    Although the invention is illustrated and described herein as embodied in a torque-transmitting, variably-flexible, locking insertion device and a method for operating the insertion device, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims. 
         [0019]    The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0020]      FIG. 1  is a diagrammatic, perspective view of a torque-transmitting, variably-flexible, locking insertion device according to the invention; 
           [0021]      FIG. 2  is a perspective view similar to  FIG. 1 , showing a working length of the insertion device; 
           [0022]      FIG. 3  is an enlarged, perspective view of the insertion device, showing details of a proximal end; 
           [0023]      FIG. 4  is a fragmentary, further enlarged, top-plan view of the proximal end of the insertion device; 
           [0024]      FIG. 5  is an even further enlarged, fragmentary, side-elevational view of the proximal end of the insertion device; 
           [0025]      FIG. 6  is a perspective view of the insertion device with an outer jacket removed; 
           [0026]      FIG. 7  is a fragmentary, enlarged, side-elevational view of the proximal end and part of the working length of the insertion device with the outer jacket removed; 
           [0027]      FIG. 8  is a view similar to  FIG. 6 , of the insertion device with a lock in an actuated condition; 
           [0028]      FIGS. 9A and 9B  are even further enlarged, fragmentary, elevational views of a distal end of the insertion device in which a locking ring is respectively shown and omitted for clarity and in which the outer jacket has been removed; 
           [0029]      FIGS. 10A and 10B  are fragmentary, perspective views of the distal end of the insertion device in which the locking ring is respectively shown and omitted for clarity and in which the outer jacket has been removed; 
           [0030]      FIGS. 11A ,  11 B and  11 C are fragmentary, longitudinal-sectional views of the distal end of the insertion device with the outer jacket removed and respectively showing two locking rings, one locking ring and no locking ring; 
           [0031]      FIG. 12  is an exploded, perspective view of the insertion device; 
           [0032]      FIG. 13  is a fragmentary, longitudinal-sectional view of the proximal end and part of the working length of the insertion device; 
           [0033]      FIG. 14  is a greatly enlarged, fragmentary, side-longitudinal-sectional view of a proximal section of the insertion device; 
           [0034]      FIG. 15  is a fragmentary, top-longitudinal-sectional view of the proximal section of the insertion device; 
           [0035]      FIG. 16  is a fragmentary, side-longitudinal-sectional view of the proximal end of the insertion device; 
           [0036]      FIG. 17  is a fragmentary, top-longitudinal-sectional view of the proximal end of the insertion device in the actuated condition; 
           [0037]      FIG. 18  is a fragmentary, top-longitudinal-sectional view of the proximal end of the insertion device similar to  FIG. 17 , in a non-actuated condition; and 
           [0038]      FIGS. 19A ,  19 B,  19 C and  19 D are enlarged, fragmentary, perspective views of the proximal end of the insertion device respectively showing a handle with a clamping plate, a body tube slid over the clamping plate, an end cap at the proximal end and a bobbin distally of the end cap. 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0039]    Referring now to the figures of the drawings in detail and first, particularly, to  FIGS. 1 and 2  thereof, there is seen a torque-transmitting, variably-flexible, locking insertion device  1  according to the invention having a working length. The insertion device  1  has a hollow body with a proximal end  2  for manipulation by an operator and for receiving an instrument  40  such as an endoscope or a colonoscope, shown in  FIG. 13 . The insertion device  1  also has a distal end  3  for insertion into a patient and for protrusion of the instrument. A handle  4  of the hollow body for control by the operator is disposed at the proximal end  2 . An outer jacket or sleeve  5  of the hollow body extends to a tip  6 , which may be formed of rubber, at the distal end  3 . As will be explained below, the handle  4  has an end cap  8 , an actuator or bobbin  9  for locking an instrument, a sliding valve or slider  10  and a forward stop  11 . The handle  4  also has a vacuum connection or nipple  12  for controlling stiffness of the device, as will be explained below as well. A corrugated tube  15  in the region of the distal tip  6 , which is illustrated in other figures, extends to the coupler  35 . 
         [0040]      FIGS. 3 ,  4  and  5  are enlarged perspective, top and side views showing the insertion device  1 , from which the end cap  8 , the actuator or bobbin  9 , the handle  4 , the sliding valve or slider  10  with the nipple  12 , the forward stop  1  and the strain relief retainer  7 , can be seen more clearly.  FIG. 3  also shows the outer jacket  5  and the distal tip  6 . 
         [0041]      FIGS. 6 and 8  are perspective views of the entire insertion device  1  and  FIG. 7  is a fragmentary side view of the proximal end and part of the working length of the insertion device, in which the outer jacket  5  has been removed. It can therefore be seen that the corrugated tube  15  extends distally beyond the strain relief retainer  7  to the tip  6  and that vertebrae  16  are clipped between several of the corrugations. Although only five vertebrae are shown in  FIGS. 6 and 8 , as many as twelve or more may be provided, depending on the working length and the application for which the insertion device is intended. The vertebrae may have slits formed radially therein to aid in slipping them over the corrugated tube. The last vertebra in the distal direction is a locking ring or termination vertebra  17 . Whereas  FIGS. 6 and 7  show the insertion device in the unlocked condition,  FIG. 8  shows it in the locked condition, which will be discussed in more detail below.  FIGS. 6 ,  7  and  8  also show staples or tendons  18  extended axially along the outer periphery of the corrugated tube  15 . 
         [0042]    As is seen in the fragmentary side, perspective and longitudinal-sectional views of  FIGS. 9A and 9B ,  10 A and  10 B and  11 A,  11 B and  11 C, the tendons or staples  18  are looped through holes or slits  22  in the vertebrae  16  and the locking ring  17 . The locking rings  17  have been omitted in  FIGS. 9B and 10B  to show details of the tendons or staples  18 . The tendons or staples  18  have ends  19  extending proximally, as shown in  FIG. 12 . The tendons or staples  18  may be fixedly connected to the locking ring  17 , such as by adhesive, weldments or solder joints. However,  FIGS. 9B and 11A ,  11 B and  11 C show that the tendons or staples  18  have a U-shape with legs passing through the holes  22  in the vertebrae  16  and cross pieces  20  disposed just distally beyond the locking ring  17 . It can be seen particularly clearly in  FIG. 11A  that the cross pieces  20  of the tendons or staples  18  are captured and prevented from migrating distally by two locking rings  17  between which the cross pieces H are sandwiched in a valley or trough between two peaks or crests of the corrugated tube  15 . 
         [0043]    The number and location of the tendons or staples  18  and the vertebrae  16  axially and circumferentially may be chosen in such a way as to vary the stiffness of the insertion device  1  in zones. For example, more tendons or staples  18  and/or more vertebrae  16  may be placed in one zone along the working length than in another zone. The zone with more tendons or staples and/or vertebrae will be stiffer. Additionally, some of the tendons or staples may not extend over the entire working length and some may be fixed to vertebrae along the working length, all of which also varies stiffness in zones. As the insertion device flexes, some of the tendons or staples which are not fixed to particular vertebrae slide in the holes or slits  22 . 
         [0044]    The exploded view of  FIG. 12  and the assembled sectional view of  FIG. 13  show the end cap  8  at the proximal end, which surrounds a rear bushing  16 . It may be seen that a marker band  28  is disposed between the actuator or bobbin  9  and the end cap  8 . A clamping plate  30 , which is also disposed within the actuator or bobbin  9 , has three partial-plates  31   a ,  31   b ,  31   c  between which three springs  32  are disposed. A body tube  33 , having slots  51 , is disposed distally of the clamping plate  30 . 
         [0045]    A coupler  35 , having grooves  23  extended axially on the periphery thereof, carries a septum seal  37  and an O-ring  38  provides a seal between the coupler  35  and the handle  4 , which is slid over the coupler  35 . Other marker bands  29  are disposed between the handle  4  and the sliding valve or slider  10  and the forward stop  11  is disposed over the distal end of the handle  4 . O-rings  24  provide a seal between the slider  10  and the handle  4 . An O-ring  34  is disposed between the forward stop  11  and the handle  4 . It may also be seen that a heat shrink tubing  39  covers the coupler  35  and an inner liner or sleeve  36  is disposed within the corrugated tube  15 . Moving distally, the corrugated tube  15  carrying the vertebrae  16 , the tendons or staples  18 , the locking ring  17  and the distal tip  6 , is shown as well. 
         [0046]    The inner sleeve  36  provides a surface over which the instrument  40  will pass smoothly within the corrugated tube  15 . The corrugated tube  15  may be formed of nylon or another suitable material. The inner sleeve  36  may be made from a sheet of polyester film, which has an adhesive coating on one side. The inner sleeve  36  is rolled around an inflatable mandrel and heated in an oven, to form a bonded seam and is sealed to an inner surface of the corrugated tube  15 . The corrugations of the corrugated tube  15  have peaks and valleys, as mentioned above. As viewed from within the corrugated tube  15 , the inner sleeve  36  adheres to the peaks and extends somewhat into the valleys of the corrugations as dimples. Therefore, as the insertion device bends, the inner sleeve  36  stays tight along the corrugations on the outside of the bend and crinkles at the inside of the bend. The peaks and valleys of the corrugations also need not be of equal length along the length of the corrugated tube  15 . For example, 70% of the length may be peaks and 30% valleys or 80% of the length may be peaks and 20% valleys. These variations will add to the adhesion of the inner sleeve  36  to the corrugated tube  15  and reduce the formation of dimples. However, a 50/50 corrugation ratio is shown in the figures. 
         [0047]    The outer jacket  5  may be formed of polyurethane or another suitable material which is similarly a flat sheet that is rolled and seamed. The outer jacket  5  extends to the distal tip  6  and the inner sleeve  36  terminates with the end of the corrugated tube  15 , the ends of which are “cuffed” to allow attachment of components. 
         [0048]    The sectional views of  FIGS. 14 and 15  show greater detail of the construction of the slider or sliding valve  10  having the nipple  12 . The slider  10 , which encircles the handle  4 , has a sliding so-called tire valve thumb grip  13  and is sealed thereto by the O-rings  24  which are disposed in recesses  14  in the handle  4 . 
         [0049]    It may be seen that the handle  4  and the coupler  35  define an annular vacuum plenum volume  41  therebetween which extends in longitudinal direction of the handle  4 . The O-ring  2  provides a seal at the proximal end of the volume  41 . A vacuum inlet/outlet hole or port  42  is formed in the body of the handle  4  and communicates with the volume  41 . The sliding valve or slider  10  also has a vacuum inlet/outlet  43  for the connection or nipple  12 . When the slider  10  is slid toward an annular stop  44 , the vacuum inlet/outlet  43  is not in alignment with the vacuum inlet/outlet hole  42 . However, when the slider  10  is slid toward an annular stop  45 , the vacuum inlet/outlet  43  and the vacuum inlet/outlet hole  42  are aligned, providing communication between the connection or nipple  12  and the volume  41 . Therefore, during operation, the slider  10  is slid toward the stop  45  to apply vacuum to stiffen the hollow body. The slider  10  is slid toward the stop  44  to vent the vacuum to atmospheric pressure making the hollow body flexible again. 
         [0050]    When vacuum is applied to the volume  41  in the manner described above, the outer jacket  5  and the corrugated tube  15  approach each other with the staples or tendons  18  sandwiched and frictionally locked therebetween. Therefore, the vacuum connection or nipple  12  acts as a device for transitioning the hollow body  4 ,  6 ,  35 ,  5 ,  36 , between a relatively flexible condition and a relatively stiff condition through the application of a vacuum. As long as the vacuum is applied, the insertion device  1  maintains it condition, whether flexed or straight. When it is desired to resume flexibility of the insertion device  1 , the vacuum is vented or replaced by air at ambient or positive pressure. This causes the corrugated tube  15  and the outer jacket  5  to release the tendons or staples  18  and the corrugated tube  15  and allows the inherent stiffness of the corrugated tube  15  to place the insertion device  1  into its normally flexible condition. 
         [0051]    The tendons, staples or wires  18  are passive elements which are not in tension at any time. The tendons or staples float within the hollow body  4 ,  6 ,  35 ,  5 ,  36 ,  15  when it is in the flexible condition, except where they are fixed to the locking rings  17 . The tendons or staples are frictionally locked by the corrugated tube  15  and the outer jacket or sleeve  5  when the hollow body is in the stiff condition. However, in both the relatively flexible condition and the relatively stiff condition, the tendons or staples have no active control imposed on them and are not pulled or constrained. 
         [0052]    As mentioned above, a comparison between  FIGS. 6 and 8  reveals that the actuator or bobbin  9  in  FIG. 6  is adjacent the end cap  8  in a non-actuated condition, while in  FIG. 8  the actuator or bobbin  9  is in an actuated condition, in which it has been moved over an extension  47  of the handle  4  and against a collar  48  of the handle  4 .  FIGS. 16 and 18  also show the actuator or bobbin  9  in the non-actuated condition, whereas  FIG. 17  shows the actuator or bobbin in the actuated condition, but in greater detail. 
         [0053]    As is seen in  FIGS. 12-13 ,  16 - 18  and  19 A,  19 B and  19 C, the three partial-plates or partial-shells  31   a ,  31   b ,  31   c  of the clamping plate  30  have detents  50  protruding therefrom.  FIGS. 17 ,  18  and  19 A,  19 B and  19 C in particular show that the springs  32  bias the partial-plates and therefore the detents  50  through slots  51  in the body tube  33  and into corresponding recesses  52  in the inner peripheral surface of the actuator or bobbin  9  in the non-actuated condition. When a sliding, so-called tire valve thumb grip  53  of the actuator or bobbin  9  is pushed by the operator of the device and the actuator or bobbin is slid distally toward the collar  48  of the handle  4 , the detents  50  slide out of the recesses  52  against the force of the springs  32 . This causes the partial-plates  31   a ,  31   b ,  31   c  to move toward each other radially and against the instrument  40 , such as an endoscope or a colonoscope represented by a dot-dash line in  FIG. 13 , for holding the instrument in place. When the actuator or bobbin  9  is slid proximally, the detents  50  once again fall into the recesses  52  due to the force of the springs  32 , so that the partial-plates  31   a ,  31   b ,  31   c  move radially outwardly and release the instrument  40 . Therefore, the actuator or bobbin  9  and the clamping plate  30  form a locking and unlocking device to be activated by the operator for locking the handle  4  to and unlocking the handle  4  from the instrument  40 . 
         [0054]      FIGS. 16 ,  17  and  18  also show the septum seal or valve assembly  37  in greater detail, as well as the end cap  8  which is inserted into the proximal end of the handle  1 . End caps  8  with various sized openings may be used in dependence on the instrument being used. The instrument passes through the hollow body and emerges at the distal tip  6 . It may be seen that the septum seal or septum valve assembly  37  has a diaphragm  37 ′ resting in a recess in the coupler  35 . 
         [0055]    A comparison of  FIGS. 19A ,  19 B,  19 C and  19 D also shows that in  FIG. 19A  merely the handle  4  with the extension  47  and the collar  48  as well as the partial-plates  31   a ,  31   b ,  31   c  are shown, while the body tube  33  has been slid over the partial-plates in  FIG. 19B , the end cap  8  has been added at the proximal end in  FIG. 19C  and the actuator or bobbin  9  has been added distally of the end cap in  FIG. 19D . 
         [0056]    The insertion device is intended to be used in a manner similar to prior art devices. Therefore, the insertion device will be placed over the endoscope. The endoscope will then be inserted into the rectum. The insertion device will then be pushed in its flexible condition, to follow the curvature of the scope. The insertion device will then be stiffened, allowing the scope to be pushed forward with less pressure exerted on the colon of the patient. This procedure can be repeated until the scope reaches the cecum. 
         [0057]    An alternative use of the insertion device is to aid in small bowel endoscopy. The insertion device is placed over the endoscope. The endoscope is inserted into the patient transorally, through the stomach and then partially into the small bowel. The insertion device is then pushed in its flexible condition, to follow the curvature of the scope. The insertion device is then stiffened, allowing the scope to be pushed forward without the scope looping in the stomach. 
         [0058]    Another use of the insertion device is for aiding in access to internal body parts, such as the gallbladder, through an opening of an internal body cavity, such as the stomach. The insertion device is placed over the endoscope. The endoscope is inserted into the patient transorally, through the stomach and then up against the internal surface of the stomach. The insertion device is then pushed in its flexible condition, to follow the curvature of the scope. The insertion device is then stiffened, allowing the surgeon to create an opening in the stomach wall without the scope looping in the stomach. Once the opening is created, the insertion device and the scope can be advanced outside the stomach. The insertion device can then be stiffened to create a stable platform to perform surgical procedures outside of the stomach. The insertion device could contain one or more features (i.e. balloons) for sealing the outer periphery of the insertion device to the stomach wall to prevent gastric fluids from exiting the stomach.