JP4437076B2 - A method of advancing an instrument through a shape-fixable device and an unsupported anatomical structure. - Google Patents

Description

(Field of Invention)
The present invention relates to an apparatus and method for placing and advancing a diagnostic or therapeutic instrument in an unsupported hollow organ but reducing the risk of patient discomfort and injury.

(Background of the Invention)
The use of colonoscopy to examine the large intestine or the inside of the colon is well known. Generally, a doctor performing a colon examination or procedure inserts a colonoscope into the anus and then advances the colonoscope into the colon. A complete examination requires the physician to advance the colonoscope to the anus and steer the left and right colonic tunes up to the sigmoid colon and cecum. Advancement of the colonoscope is generally accomplished by manipulating the movable tip of the colonoscope. The movable tip of the colonoscope is controlled by the physician at the proximal end of the device, in addition to torque the microscope forward and pull backward.

  However, problems uniformly arise when a colonoscope is advanced through colonic folds (eg, sigmoid and left and right colonic folds). These problems arise because the colon is flexible and has unpredictable anchoring points in the body cavity and can easily expand. Thus, after the movable tip of the colonoscope is curved to enter a new area of the colon, the main direction of the force applied by the physician driving the proximal end of the device into the patient's colon is Not the direction of the movable tip. Instead, this force is directed along the colonoscope axis towards the previous bend, resulting in deformation or misalignment of the colon wall.

  The load imposed by the colonoscope on the colon wall can have a myriad of possible effects (the extent of colon penetration or incision that can result from discomfort to intermittent convulsive contractions of the colon). Therefore, the colonoscope cannot be advanced to the cecum in up to 1/6 of all cases.

  To overcome some of these difficulties, it is known to use a guide tube that allows the colonoscope to travel through the rectum. One such device is described in US Pat. No. 5,779,624 to Chang et al. An alternative approach for inserting a colonoscope through a bent area is needed, and a portion of this device is mechanically mounted in the bent area as described in US Pat. No. 4,601,283 to Chikama. Actuate to make it straight.

  Many patients feel uncomfortable with the operation of such previously known devices. This is because the S-shaped portion of the colon is almost linearly shaped by the guide tube. Due to the stiffness of this guide tube, careless manipulation of the guide tube creates a risk of colon injury.

  Other previously known devices and methods use an overtube with variable altitude, so that the overtube can be inserted through a flexible bent structure and then the overtube Selectively strengthens against the bending force caused by passing through the colonoscope. One example of such a device is described in US Pat. No. 5,337,733 to Bauerfiend. The device is described that the patient includes an inner wall and an outer wall having opposite ribs spaced from an air inflated ring. These ribs are selectively withdrawn to engage each other, and the rigid structure is formed by removing this ring.

  Another previously known endoscopic device for delivering aneurysm clips within hollow organs or blood vessels is described in US Pat. No. 5,174,276 to Crockerd. The device is described to include a conduit formed from a plurality of elements that can each be formed in relation to each other and become rigid when subjected to tension. The device has been described as being particularly useful in neurosurgery, and the variable stiffness of the device is useful to provide a stable platform for neurosurgery (eg, stopping aneurysms). is there.

  Previously known devices and methods provide some suggestions for solving the difficulties encountered in advancing diagnostic or therapeutic instruments that can easily inflate body organs, but are commercially available devices There is almost no. The exact reason for this lack of success is not clear, but the previously known devices seem to have caused some problems.

  For example, the devices described in the Bauerfiend and Crockerd patents can grasp tissue between the endoscope / colon endoscope and the distal end of the overtube or conduit when the endoscope is moved, Or it seems to cause a danger of pinching. Neither device also provides any degree of maneuverability and must be advanced along a pre-arranged microscope. Furthermore, the bulk of the proximal tensioning system described in Crocker is expected to interfere with the operation of the endoscope. Other shortcomings of other previously known devices can be related to the complexity or cost of such devices or the lack of suitable materials. In any case, there is an unmet need for a device that solves a long-standing problem in the field of endoscopy and colonoscopy.

  In view of the above, it would be desirable to provide an apparatus and method that facilitates the placement of diagnostic or therapeutic instruments within a readily inflatable hollow body organ (eg, esophagus or colon).

  Providing an apparatus and method that allows a diagnostic or therapeutic device to advance into a hollow body organ and allowing the device to pass through a bent structure without the need to straighten the passage of an already traversed organ It is further desirable to be able to

  It would also be desirable to provide an apparatus and method that facilitates the placement of diagnostic or therapeutic instruments within a hollow body organ that can be easily inflated. This reduces the risk of tissue being inadvertently trapped or caught between the device and the anterior or posterior instrument when a diagnostic or therapeutic instrument is manipulated through the hollow body organ Means.

  Still further, it is desirable to provide an apparatus and method that provides a low-cost, single-use, easily operable guide for inserting a diagnostic or therapeutic instrument into a hollow body organ.

  Still further, it would be desirable to provide an apparatus and method that provides a low cost, easily operable guide for inserting a diagnostic or therapeutic instrument into a hollow body organ. Here, a part of the device is disposable after a single use and the rest of the device is reused.

  Still further, it is desirable to provide a device having a selective fixation shape for inserting a diagnostic or therapeutic instrument into a hollow body organ, which facilitates manipulation of the proximal end of the diagnostic or therapeutic instrument. To do.

  It is further desired that a plurality of diagnostic or therapeutic devices can be placed in a hollow, non-supporting organ so that at least one of the devices can be retrieved while the other device is held in place. And can be rearranged.

  It would further be desirable to provide an apparatus and method that facilitates the placement of diagnostic or therapeutic instruments within an easily inflatable hollow body organ, reducing the risk of reconfiguration of the apparatus in the event of failure of the device. Decrease.

  It is still further desirable to provide an apparatus and method that facilitates placement of a diagnostic or therapeutic instrument within an easily inflatable hollow body organ, substantially maintaining the axial length of the apparatus.

(Summary of the Invention)
In view of the above, it is an object of the present invention to facilitate the placement of diagnostic or therapeutic devices within a hollow body organ (eg, esophagus or colon) that is easily inflatable or unpredictably supported. It is an object to provide an apparatus and method.

  It is a further object of the present invention to allow a diagnostic or therapeutic device to be advanced into a hollow body organ and to meander the anatomical structure of this device without having to straighten the already traversed organ passage It is an object to provide an apparatus and method that facilitates passage through a device.

  It is also an object of the present invention to provide an apparatus and method for facilitating placement of a diagnostic or therapeutic instrument within an easily inflatable hollow body organ, the instrument comprising the diagnostic Means are provided for reducing the risk of inadvertent puncture or capture of tissue as the instrument or treatment instrument is manipulated through the hollow body organ.

  A still further object of the present invention is to provide an apparatus and method that provides a low cost, single use, easily manufacturable guide for inserting a diagnostic or therapeutic instrument into a hollow body organ. is there.

  Another object of the present invention is to provide an apparatus and method that provides a low cost, easily manufacturable guide for inserting a diagnostic or therapeutic instrument into a hollow body organ, wherein A portion of the device can be disposed of after a single use, and the remaining portion of the device can be reused.

  Still further, an object of the present invention is a device for inserting a diagnostic or therapeutic instrument into a hollow body organ, but selectively locking which facilitates manipulation of the proximal end of the diagnostic or therapeutic instrument It is to provide a device having a shape.

  Yet another object of the present invention is to provide a plurality of diagnostic or therapeutic devices that are hollow so that at least one of these devices can be withdrawn and structurally changed while the other devices are left in place. It is possible to be placed in an unsupported organ.

  A further object of the present invention is to facilitate the placement of a diagnostic or therapeutic instrument within an easily inflatable hollow body organ that reduces the risk of structural changes in the device in the event of a device failure. An apparatus and method is provided.

  A still further object of the present invention is an apparatus and method for facilitating placement of a diagnostic or therapeutic instrument within an easily inflatable hollow body organ that substantially maintains the axial length of the apparatus. Is to provide.

  These and other objects of the present invention include a proximal handle, an overtube coupled to the proximal handle and having a distal region, an atraumatic tip disposed in the distal region, and an overtube shape. For selective fixation, to help one or more diagnostic or therapeutic instruments pass through the tortuous or unsupported anatomical structure of a hollow body organ without expanding the wall of the organ This is achieved by providing an apparatus comprising the mechanism. The device includes a main lumen that extends between a handle, an overtube and an atraumatic tip, through which a diagnostic or therapeutic instrument (eg, an endoscope or colonoscope) can move.

  The handle extends from the patient, for example, through the mouth or anus (where the handle can be manipulated by a physician). The proximal handle may form part of a single use disposable device or may be separated from the overtube and reusable. Alternatively, the overtube may comprise a disposable single use cover that fits over the reusable structure. The overtube can be angled with respect to the working axis of the handle so that the handle does not interfere with the operation of diagnostic or therapeutic instruments inserted through the overtube.

  An overtube constructed in accordance with the principles of the present invention may comprise a plurality of telescoping elements that can be selectively pulled by actuation of a tooth wheel, pneumatic mechanism, or shape memory material. Alternatively, the overtube comprises a series of interconnected links surrounded by a selectively actuable clamping mechanism, formed of a material having a variable durometer and surrounded by a plurality of helical links surrounded by a clamping mechanism. It may comprise a tubular member comprising, a thermoresponsive polymer or alloy, an elongated flexible tube formed from an electroactive polymer, or a series of overlapping or nested links made from a shape memory material. The overtube may comprise any of a number of aids for facilitating the passage of diagnostic or therapeutic instruments through the main lumen (comprising a lubricating liner, rail or roller).

  The tension system may provide a fail safe mode that reduces the risk of structural changes in the overtube in the event of a mechanism failure. The fail-safe mode can equalize the compression clamp load applied to the overtube when the overtube is stiffened, and stiffen the overtube without substantial proximal movement of the distal region Can be configured.

  The liner can be made from a thin, flexible material, can have a hydrophilic coating, can comprise a torsion resistant coil, or a combination thereof. Alternatively, the liner can be a disposable sheath that can be removed from the overtube to allow reuse of the structure inside the overtube.

  The atraumatic tip of the present invention is preferably configured to reduce the risk of capturing or pinching tissue between an overtube and a diagnostic or therapeutic device that selectively moves through the overtube. The This is preferably accomplished by a traumatic tip that applies a radially outward load to the wall of the hollow body organ near the distal region where the diagnostic or therapeutic device exits the device.

  Furthermore, the distal region of the overtube preferably allows a steerable tip of a diagnostic or treatment device disposed within the distal region to deflect the distal region of the overtube in a desired direction. A flexible portion. This allows the overtube to be easily advanced with the steerable tip of the diagnostic or treatment device.

  Further features of the invention, its nature and various advantages will be more apparent from the accompanying drawings and the following detailed description of the preferred embodiments.

(Detailed description of the invention)
Referring to FIG. 1, for inserting and advancing a diagnostic or therapeutic instrument into a hollow body organ (exemplarily the patient's colon C) having a serpentine or unsupported anatomy. The problems associated with previously known devices and methods are described. The colon C includes a sphincter SM located between the anus A and the rectum R. The rectum R is connected to the sigmoid colon SC via the sigmoid colorectal junction RJ. The sigmoid colon SC connects to the descending colon DC, which in turn binds to the transverse colon TC via the left colonic curvature LCF. The transverse colon TC is also coupled to the ascending colon AC and cecum CE by the right colonic curvature RCF, which receives waste products from the small intestine.

  As shown in FIG. 1, a colonoscope 10 having a steerable distal tip 11 is typically inserted into the rectum R through the anus A and then through the sigmoid colorectal joint RJ. Steered into the sigmoid colon SC. As shown in FIG. 1, the distal tip 11 of the colonoscope 10 is advanced through the sigmoid colon SC and deflected into the descending colon DC. By further propelling the colonoscope by the physician, the region 12 of the colonoscope is loaded into the sigmoid colorectal joint RJ, as indicated by the dotted lines 12 ′ and RJ ′ in FIG. May cause movement of parts.

  Such swelling can cause patient discomfort or convulsions and, if not noticed, can cause damage to the colon. The possibility that the movement of the colonoscope causes dilation, discomfort or convulsions is also great if the colonoscope has to pass through the left colonic curvature LCF and the right colonic curvature RCF, and as a result of such trials The majority ends before the physician can advance the distal tip 11 to the cecum CE.

  The present invention relates to a serpentine or unpredictably supported anatomical structure of a hollow body organ (eg, esophagus or colon) while reducing the risk of organ expansion or damage. Devices and methods are provided for placement through. A device constructed in accordance with the present invention provides an endoscope by selectively locking the shape of the overtube portion of the device while preventing tissue from being captured or pinched between the overtube and the scope. Or, the colonoscope can be easily advanced into the patient's tortuous or unsupported anatomy.

  Referring now to FIG. 2, the apparatus 20 of the present invention is described. Device 20 includes a distal region 23 having a handle 21, an overtube 22, and an atraumatic tip 24. The handle 21 includes a lumen 25 that extends from a Toughy-Borst valve 26 through an overtube 22, a distal region 23, and an atraumatic tip 24. Lumen 25 is configured to facilitate passage of a commercially available standard colonoscope (eg, colonoscope 10) therethrough. The Toughy-Borst valve 26 may be actuated to releasably lock the colonoscope 10 to the device 20 when the colonoscope 10 is inserted into the lumen 25. As described herein below, the overtube 22 can be selectively transitioned between a flexible state and a rigid shape-fixed state by an actuator 27 disposed on the handle 21. Configured.

  In FIG. 3A, an exemplary embodiment of overtube 22 includes multiple telescoping elements 30. For illustrative purposes, the telescoping element 30 is shown spaced apart, but the element 30 is arranged such that the distal surface 31 of one element 30 covers the proximal surface 32 of an adjacent element. It should be understood that Each telescoping element 30 has a central hole 33 for receiving the colonoscope 10, preferably two or more tension wire holes 35. When assembled as shown in FIG. 2, the telescoping element 30 is disposed in a contacted manner by a plurality of tension wires 36 extending through a tension wire lumen 28 defined by the tension wire holes 35. Fastened at surface 31 and proximal surface 32. The tension wire 36 is preferably made from a superelastic material (eg, a nickel titanium alloy) to provide flexibility, bending resistance, and smooth movement through the tension wire hole 35 of the tension wire. Alternatively, the tension wire can be made from braided stainless steel, single stainless steel wire, Kevlar, high tension monofilament thread, or combinations thereof. These materials are provided for illustrative purposes only and should not be construed as limited in any manner.

  In a preferred embodiment, the ratio of the diameter of the tension wire 36 to the diameter of the tension wire hole 35 is approximately in the range of 1/2 to 2/3. Applicants have observed that this provides a smooth relative motion between the tension wire and the telescoping element even when the overtube 22 is warped. Although a higher ratio is desirable, such a configuration allows the tension wire hole 35 to bite into the tension wire 36, thereby limiting the movement of the tension wire through the tension wire hole. Conversely, while Applicants contemplate that a smaller ratio provides even smoother relative movement, the resulting increase in the thickness of the wall 34 of each telescoping element 30 is undesirable.

  In a preferred embodiment, the adjacent surfaces 31 and 32 of each telescoping element 30 mate with the next adjacent element so that the surfaces 31 and 32 can rotate relative to each other when the tension wire 33 is loosened. The tension wire 36 is fixedly coupled to a tension mechanism disposed in the handle 21 at the distal end and at the distal end of the overtube 22 and at the proximal end. When actuated by the actuator 27, the tension wire 36 provides a load that holds the distal surface 31 and proximal surface 32 of the telescoping element 30 together in the current relative orientation, thereby fixing the shape of the overtube 22. To do.

  When the load on the tension wire 36 is released, the tension wire 36 provides relative angular motion between the telescoping elements 30. This in turn makes the overtube 22 sufficiently flexible to bend through a serpentine passage through the intestine. However, when the tension mechanism is activated, the tension wire 36 is retracted proximally to apply a clamping load to the telescoping element. This load prevents further relative movement between adjacent elements 30 and stiffens the overtube 22, so that any distal force applied to the colonoscope 10 causes the overtube 22 to move through the colon. Rather than abutting against the wall, the distal tip 11 is advanced further into the colon. A fixed shape overtube absorbs and disperses the vector force and shields the colon wall.

  In a preferred embodiment, the radius of curvature of the proximal surface 32 is approximately the same as the radius of curvature of the distal surface 31. In particular, the ratio of the radius of curvature of the distal surface 31 to the radius of curvature of the proximal surface 32 is about 0.9 to 1.0. Furthermore, the coefficient of static friction between the distal and proximal surfaces is preferably in the range of about 0.2 to 1.4 (based on ASTM standard D1894). This structure appears to generate sufficient frictional forces between these surfaces to prevent relative movement between adjacent elements when the overtube 22 becomes stiff.

  The telescoping element 30 can be configured to provide a stack of overtubes 22 that is a function of growth height. As defined in FIG. 3B, the increased height H is an increase in the longitudinal length of the overtube 22 when one telescoping element 30 is nested within another telescoping element 30. In order to accommodate the radius of curvature that can be obtained with a commercially available standard colonoscope, the increased height H is preferably about 0.31 inches or less, more preferably about 0.16 inches. This provides an overtube 22 that is sufficiently flexible to assume a radius of curvature of about 0.95 inches or less. If the overtube 22 is larger or smaller in size and / or needs to accommodate other endoscopes or medical devices that can take different radii of curvature, or if the overtube is a denser anatomical Where it is necessary to accommodate constraints, Applicants contemplate that the increased height H can be directly or inversely proportional to changes in the dimensions of the overtube 22. Applicants note that the previous geometric features of the telescoping element 30 (omitted from FIG. 3B for illustrative purposes) do not cause material interference or influence on the tension wire hole. To do.

  Preferably, the telescoping element 30 is molded from a polymer filled with glass fibers, carbon fibers or combinations thereof. In a particularly useful embodiment, the telescoping element 30 is molded from 20-40% by volume glass fiber, 20-40% by volume carbon fiber, or 20-40% by volume glass fiber and polyurethane filled with carbon fiber. Is done. An example is Isoplast 2540, which is available from Dow Chemicals, Midland, MI. Applicants have found that such materials increase the friction between adjacent elements, which advantageously reduces the risk of relative angular motion between these adjacent elements when the overtube 22 becomes stiff. Thus, it has been observed that the risk of undesired reconfiguration of the overtube 22 with its shape fixed is reduced. Although higher amounts of glass and / or carbon fibers are desirable, such materials appear to reduce the structural integrity of the telescoping elements.

  Furthermore, the fiber-embedded polymer increases the stiffness of the telescoping element 30, so that the longitudinal shrinkage of the overtube 22 is significantly reduced when the overtube becomes stiff. When the tension wire 36 is actuated to apply a compression clamp load to the overtube 22, longitudinal contraction occurs. This resulting pressure eliminates any groove between adjacent elements 30 and deflects the proximal portion of each telescoping element radially outward. This shortens each element in the longitudinal direction so that the overtube 22 contracts in the axial length.

  Typically, an overtube made from a polymer telescoping element that does not contain glass fibers and / or carbon fibers contracts about 8-12% in the longitudinal direction when applied with a compression force of about 30 lb. To do. In comparison, when a compression load of 30 lb is applied to a telescoping element made from a polymer embedded with glass and / or carbon fibers, as in the preferred embodiment of the present invention, this overtube is about 4 % Shrink only. Advantageously, this reduces trauma to the patient by providing higher accuracy during use of the present invention, which is particularly important in sensitive procedures. In addition to glass-filled polymers and / or carbon-filled polymers, the telescoping element 30 may also include other polymers and / or metals (eg, polyurethane, polyvinyl chloride, polycarbonate, nylon, titanium, tungsten, stainless steel, aluminum or the like It will be apparent to those skilled in the art that it can be molded or machined from Indeed, the metal telescoping element 30 undergoes a smaller longitudinal shrinkage than that experienced by the fiber embedding polymer. These materials are provided for illustrative purposes only, and those skilled in the art will recognize a number of additional materials suitable for use with the devices of the present invention.

  Referring now to FIG. 4, an exemplary embodiment of the distal region 23 and the atraumatic tip 24 will be described. The distal region 23 comprises a flexible bend resistant coil 41 encapsulated in a flexible layer 42. Layer 42 preferably comprises a soft elastic hydrophilic coating material (eg, silicone or rigid rubber) and terminates at a distal end in an elongated portion 44 that forms an atraumatic tip 24. At the proximal end, the layer 42 is connected to or formed integrally with a liner 43 that extends through the hole 33 of the telescoping element 30 to the handle 21. In a preferred embodiment, the liner 43 has a flexible bend resistant coil 29 made from a thin flexible material and embedded therein as needed. The material of the liner 43 preferably has a high durometer in the range of 30-80D, but may have a lower or higher durometer.

  The layer 42 is preferably connected to or integrally formed with a flexible elastic skin 45 to form a sheath 48 that encapsulates the telescoping element 30 in the annular chamber 46. Turn into. Skin 45 provides a relatively smooth outer surface for overtube 22 and prevents tissue from being captured or pinched during relative rotation of adjacent telescoping elements 30. In a preferred embodiment, the total thickness T of skin 45, telescoping element 30 and liner 43 is about 2.5 mm or less, more preferably 1 mm or less. For example, skin 45 can have a thickness of 0.13 mm, or more preferably 0.1 mm, element 30 can have a thickness of 1.9 mm, more preferably 0.7 mm, and liner 43 can be It may have a thickness of 0.38 inches, more preferably 0.15 mm.

  According to one aspect of the present invention, the colonoscope 10 can be positioned such that its distal tip 11 is positioned in the distal region 23 so that the steerable distal tip 11 deflection is: Angular deflection is provided for distal region 23 and atraumatic tip 24. To ensure that there is no significant relative motion between the colonoscope 10 and the device 20, the Toughy-Borst valve 26 is tightened to engage the device 20 with the colonoscope. Thus, the colonoscope 10 and the distal region 23 can be advanced simultaneously through the colon, where the distal tip of the colonoscope provides steering capability for the device 20. Thus, the device 20 is advantageously advanced with the colonoscope 10 when the overtube 22 is in a flexible state, and the relative movement between the device 20 and the colonoscope 10 is achieved with the overtube 22 fixed in shape and the colon. Is reduced to a distance to prevent the expansion of.

  Still referring to FIG. 4, a tension wire termination 47 is described. The termination 47 illustratively comprises a ball welded or molded to the end of the tension wire 36, which can be pulled through the tension wire hole 35 of the distal-most telescoping element 30. Guarantee that there is no. This ensures that the telescoping element cannot loosen when the overtube 22 is placed in the patient.

  Alternatively, the termination 47 may comprise a nut formed at the end of the tension wire 36 or any suitable fastener that prevents the tension wire from being pulled through the tension wire hole of the most distal telescoping element. . Advantageously, the skin 45 provides further assurance that all of the telescoping element 30 can be safely retrieved from the patient's colon in the unlikely event of tension wire failure.

  Referring now to FIGS. 2 and 5, overtube 33, liner 43, and tension wire 36 within lumen 25 extend from distal region 23 through overtube 22 to handle 21. Within the handle 21, each tension wire 36 passes through a wire lock release 51 fixedly attached to the handle 21 and a wire lock 52 disposed on the slide block 53. Each tension wire 36 terminates in a wire tension spring 54 that maintains the tension wire 36 in a light tension state even when the overtube 22 is in a flexible state. The degree of tension provided by the wire tension spring 54 is not sufficient to hold adjacent telescoping elements 30 together, but on the other hand, does not form a groove between adjacent telescoping elements and overtube 22. Helps manage tension wires that tighten or loosen when forming various bends.

  The slide block 53 is adjusted to slide along the rail 55 disposed between the restriction blocks 56 and 57, and a rigid block having a hole through which the rail 55 extends and a number of tension wires 36 are used. With the additional number of holes required for the The rack gear 58 is fixedly connected to the slide block 53. The rack 58 engages with the pinion gear 59, which is then driven by a bidirectional pawl 60 connected to the actuator 27. Pinion gear 59 can be selectively engaged by either tip 61 or 62 of bidirectional pawl 60 depending on the position of selector switch 63.

  When the tip 61 is selected to engage the pinion gear 59, the compression action (exemplarily handgrip 64) applied to the actuator 27 moves the rack 53 in direction D of FIG. Stretch is applied to the tension wire 36. The repetitive action of the handgrip 64 moves the slide hook 53 gradually further in the direction D, thereby applying an increasing clamping load on the telescopic element 30. Any slack length of the tension wire 36 that extends under the slide block 53 is tightened by a wire extension spring 54. As will be discussed in more detail below with respect to FIG. 6, the wire lock 52 (which is attached to the slide block 53) engages the tension wire 36 simultaneously with the movement of the slide block 53 in direction D, and this The tension wire 36 is retracted.

  Instead, when the tip 62 is selected by the selector switch 63 and engages the pinion gear 59, repetitive actuation of the handgrip 64 moves the slide block 53 in the direction U, thereby causing the telescoping element 30 by the tension wire 36. Loosen the tensile load applied to the. Repeated actuation of the handgrip 64 advances the slide block 53 in direction U until the wire lock release 51 engages the wire lock 52 and releases all tension from the tension wire 36 except that provided by the wire tension spring 54. To do. This action gradually reduces the tethering force exerted on the telescoping element 30 and, when the wire lock release 51 engages the wire lock 52, until the overtube returns to its most flexible state. 22 becomes increasingly more flexible.

  Referring to FIG. 6, the wire lock 52 and lock release 51 are described in more detail. The wire lock 52 includes a jaw 65 disposed within the collet 66. The collet 66 includes a tapered conical hole 67. The jaw 65 has a sloped outer surface 68 and teeth 69 and is biased by a spring 70 against the surface formed by the tapered conical hole. The tooth portion 69 is configured to engage with the tension wire 36 under the biasing force of the spring 70. When the slide block 53 is moved in direction D (see FIG. 5), the jaw 65 engages the tension wire 36 and grips the tension wire 36 and retracts the tension wire in direction D.

  In order to remove the tooth 69 from the tension wire 36, for example, when it is desired to return the overtube 22 to a flexible state, the slide block 53 is actuated as previously described to provide the direction U. Moved to. Further actuation of the slide block 53 to the restriction block and the wire lock release 51 extends the wire lock release 51 toward the tapered conical hole 67 and pushes the jaw 65 backwards against the bias of the spring 70. . Once the tension wire 36 is released from the jaw 65, the overtube 22 returns to its most flexible state.

  With reference to FIGS. 7A-7C, a method of using apparatus 20 will be described. Colonoscope 10 and overtube 22 can be inserted into the patient either simultaneously or by first backloading the overtube to the colonoscope. To perform simultaneous insertion, the colonoscope 10 is introduced into the lumen 25 of the handle 21 until the distal tip 11 of the colonoscope is placed in the distal region 23. The Toughy-Borst valve 26 is actuated to lock the device 20 to the colonoscope 10. As one unit, the colonoscope 10 and overtube 22 are inserted into the patient's rectum R and steered around the sigmoid colorectal joint RJ. As discussed above, the steerable distal tip 11 provides angular deflection to the flexible tip 24 and the tip 24 around a serpentine curve (eg, sigmoid colorectal joint RJ). Can be used to link. Once the distal tip 11 and tip 24 have passed the sigmoid colorectal joint RJ, the current shape of the overtube 22 is locked in the manner discussed above and the colonoscope 10 is moved to the S Providing a rigid channel that can be advanced further through the colon without widening the sigmoid colorectal joint RJ. Once the distal tip 11 of the colonoscope 10 has passed through the sigmoid colon SC, the overtube 22 is released from its rigid state and advanced along the colonoscope 10 until it crosses the sigmoid colon SC. It is done. Again, the current shape of the overtube 22 is locked to provide a rigid channel for advancement of the colonoscope 10. The above steps can be repeated to pass through the remaining colon (eg, left colonic curvature LCF and right colonic curvature RCF). In this way, colonoscope 10 and overtube 22 can pass through the serpentine curve of the colon without expanding the colon and thereby causing discomfort, cramps or trauma.

  Alternatively, rather than inserting both the colonoscope 10 and the overtube 22 into the patient simultaneously, the device 20 can be first backloaded to the colonoscope. First, an overtube 22 is attached to the colonoscope 10 and is positioned proximal to the distal tip 11 as shown in FIG. The colonoscope 10 is then inserted into the patient's rectum R and advanced around the sigmoid colorectal joint RJ. The overtube 22 is advanced along the colonoscope 10 to the patient's rectum R, using the colonoscope 10 as a guide rail for passing through the sigmoid colorectal joint RJ. Once the overtube 22 has crossed the sigmoid colorectal joint RJ to the position shown in FIG. 7A, the shape of the overtube 22 is locked and the colonoscope 10 can be advanced further toward the colon. Provide a channel. In order to pass through the remaining colon, the steps discussed with respect to FIGS. 7B-7C may be performed.

  With reference to FIG. 9, an alternative embodiment of the handle 21 is described. Similar to the handle 21 of FIG. 5, the handle 71 also embodies a ratchet-type tension mechanism, but in this embodiment the overtube 22 can be isolated from the handle 71 so that the handle 71 is for repeated use. Can be sterilized. The handle 71 includes a housing 72 having an actuator 73 that engages a tooth 74 disposed along the length of the rod 75, which defines a working axis W of the handle 71. The push knob 76 is attached to the proximal end of the rod 75 so that when the pawl 77 is released, the rod 75 can be pushed in the distal direction. The pawl 77 engages the tooth portion 74 of the rod 75 to prevent the rod 75 from moving in the distal direction. The spring 78 biases the pawl 77 against the teeth 74 of the rod 75 and provides a one-way ratchet effect when the actuator 73 is moored.

  As in the embodiment of FIG. 5, the tension wire 36 extends through a wire lock release 79, a wire lock 80 and is coupled to a wire tension spring 81. Wire lock 80 is attached to block 82, which moves within housing 72 in response to movement of rod 75. Wire lock 80 and wire lock release 79 operate in the same manner as described with respect to FIG.

  In operation, a mooring actuator 73 (exemplarily a hand grip) causes the fork 83 to move the rod 75 proximally so that the pawl 77 captures the next most distal tooth 74. This movement can also cause the wire lock 80 to engage and grip the tension wire 36 and retract the tension wire proximally. With further actuation of the actuator 73, the overtube 22 can become stiff in the manner described above. The spring 78 maintains the pawl 77 in continuous engagement with the teeth 74, thereby preventing the rod 75 from moving distally.

  If it is desired to make the overtube 22 more flexible, the pawl 77 is released and the knob 76 is pushed in the distal direction so that the wire lock 80 engages the wire lock release 79. As described above, this releases the tension wire 36 from the wire lock 80 and allows the overtube to assume its most flexible state.

  According to one aspect of the invention, the overtube 22 of the embodiment of FIG. 9 can be interchangeably removed from the yoke 84 of the handle 71. Further, the tension wire 36 may further comprise a connector 85 that allows the tension wire to be removed. With such a configuration, after a single use, the overtube can be removed and discarded, while the handle can be sterilized and reused.

  The yoke 84 is also configured to position the overtube 22 so that the longitudinal axis L of the overtube is offset from the working axis W by a predetermined angle β. This arrangement prevents the handle 71 from obstructing progression into the lumen 25 of the colonoscope 10.

  According to yet another aspect of the present invention, the overtube 22 includes an atraumatic tip 86 that includes a soft foam-like material. The atraumatic tip 86 not only provides for advancement of the overtube 22 in the passage of serpentine body structures, but also opens the organ wall as described herein below with respect to FIG. 14A. Through this opening, the colonoscope helps maintain a safe distance from the organ wall, which reciprocates by radially expanding the organ wall near the tip. Thus, the atraumatic tip 86 reduces the likelihood that tissue will be trapped or pinched in the lumen 25 when the colonoscope is manipulated.

  Referring now to FIGS. 10-16, an alternative tension mechanism is described, which provides a fail-safe mode that reduces the risk of undesired reconfiguration of the overtube if the tension mechanism fails. Can do. When the overtube 22 is in a rigid state, the following tension mechanism is configured to self-homogenize the compressive load applied to multiple telescoping elements so that, for example, if the tension wire breaks, The overtube either softens and becomes flexible or maintains its shape fixed.

  FIG. 10A schematically illustrates components of a first embodiment of a femoral tension mechanism having a plurality of distal pulleys 87 operatively connected via proximal tension wires 88. Proximal tension wire 88 is slidably disposed within proximal pulley 89. Each tension wire 90 connects adjacent tension wire lumens 28 via respective distal pulleys 87. For example, as shown in FIG. 10A, when four tension wire lumens 28a-28d are provided, the first tension wire 90a passes from the tension wire lumen 28a through the first distal pulley 87a. , Extending to the adjacent tension wire lumen 28b. Similarly, the second tension wire 90b extends from the tension wire lumen 28c through the second distal pulley 87b to the adjacent tension wire lumen 28d.

  This configuration equalizes the tension in the tension wire 90 so that the proximal force F applied to the proximal pulley 89 is evenly distributed through the tension wire 90. If one of the tension wires breaks, this configuration causes the overtube 22 to soften into its flexible state. This is because the loss of tension in any of the tension wires is transmitted through the pulley system to the remaining tension wires.

  The tension wires 90a and 90b can include either two separate length wires, or a single length wire (which is wound back after passing through the most distal telescoping element 30) Will be apparent to those skilled in the art. Further, FIG. 10A shows a tension wire 90 that extends through an adjacent tension wire lumen 28, but this tension wire instead passes through wire lumens arranged diametrically opposite one another, as shown in FIG. 10B. Can extend. The tension wire 90 may preferably be made from a superelastic material (eg, a nickel titanium alloy), but may be made from braided stainless steel, single stainless steel wire, Kevlar, high tension monofilament thread, or combinations thereof. These materials are provided for illustrative purposes only and should not be construed as limited in any manner.

  In the alternative embodiment shown in FIG. 10C, the proximal pulley 89 is eliminated and the distal pulley 87 is secured to each other, for example, by welding, so that one pulley manifold is formed. Proximal force F applied to the pulley manifold is uniformly distributed through tension wires 90 extending through respective distal pulleys 87 from opposing tension wire lumens 28 disposed in the overtube 22. To do. If the tension wire 90 includes two separate lengths of wire, the risk of the overtube reconfiguring is reduced if one of these wires breaks. This is because the tension in the overtube 22 is symmetrically balanced as defined by the unbroken tension wire. If the remaining tension wire breaks, the tension wire loosens and becomes flexible. If the tension wire 90 includes a broken length of wire, the overtube will immediately loosen and become in its flexible state, so that even if the tension system fails, the desired overtube Reduce the risk of no configuration.

  In addition, Applicants have noted that the device of the present invention also includes only one distal pulley 87 connected to the overtube 22 via one tension wire 90 disposed through diametrically disposed tension wire lumens 28. It was observed that When a proximal force is applied to one distal pulley, this force is distributed through one tension wire and a contrasting compression clamp load sufficient to fix the overtube shape is applied to this overload. It affects the tube 22. If the tension wire 90 breaks, the overtube 22 immediately softens to its flexible state, thereby reducing the risk of unwanted reconfiguration of the overtube, even if the tensioning system fails.

  Referring now to FIG. 11, the lumen 25 and tension wire 90 within the overtube 22 extend from the distal region of the device through the overtube 22 to the handle 91. At handle 91, this tension wire is slidably connected to distal pulley 87, which in turn is slidably connected to proximal pulley 89. Proximal pulley 89 is coupled to and moves slide block 92, which is adjusted to move along a passage 93 disposed in housing 94. Plunger 95 is rotatably attached to slide block 92 at the proximal end and is slidably disposed within the plunger housing at the distal end.

  A plunger housing 96 is pivotally attached to the actuator 27 (eg, hand grip 97). In order to tilt the handgrip 97 with respect to the operation, a compression spring 98 is coaxially arranged around the plunger 95 without supplying external force. The compression spring 98 maintains the tension wire 90 at a constant tension when the tensioning mechanism is actuated to press the clamping load. Advantageously, when the shape of the overtube 22 is fixed, if the adjacent telescoping element (nesting element) moves slightly, the proximal deflection of the compression spring 98 immediately moves the slide block 92 proximally. Reconstructing the overtube, proceeding in the direction of to maintain a relatively constant tension load within the tension wire 90, thereby returning to a flexible state that could otherwise occur if the compression spring 98 does not work Reduce the risk of

  The handgrip 27 also includes a pawl 99 that is arranged to engage the tooth 100 on the ratchet bar 101 and prevents distal movement of the slide block 92. The ratchet bar 101 is pivotally installed in the housing 94 by a spring (not shown), which with the aid of a compression spring 98 tilts the pawl 99 with respect to the teeth 100 of the ratchet bar 101 and provides a hand grip. Provides a one-way ratchet effect when 97 is gripped strongly.

  In operation, the pawl 99 captures the adjacent proximal tooth 100 by squeezing the handgrip 97. This movement also supplies a compression force transmitted to the slide block 92 to the compression spring 98. The proximal component of the compressive force causes the slide block 92 to move along the passage 93, causing the tension wire 90 to retract proximally, so that the clamping load is pushed onto the telescoping element in the overtube 22. It is done. With further actuation of the handgrip 97, the overtube 22 becomes increasingly stiff in the manner described above.

  Advantageously, the most proximal tooth 100a is placed on the ratchet bar 101 at a predetermined proximal position and completely moves the overtube 22 from its flexible state to a fixed shape. Allows a single actuation of the handgrip 97. Furthermore, the pawl 99 advances the handgrip 97 closer to the housing 94, thus increasing the mechanistic advantage of the handgrip operation. More specifically, since the hand grip 97 gradually becomes horizontal, the magnitude of the proximal component of the force transmitted by the compression spring 98 increases. Accordingly, more force is transmitted and the tension in the tension wire 90 is increased, thus increasing the applied clamping load and making the overtube 22 stiff.

  If it is preferable to make the overtube 22 flexible, the pawl 99 is released from engagement with the tooth 100 by rotating the ratchet bar 101 proximally. Release of the compressive load applied to the compression spring 98 causes the hand grip 97 to rotate in the distal direction and the slide block 92 to contract in the distal direction. This sufficiently relaxes the tension wire 90 so that the tension wire retains little or no tension, thereby allowing the overtube 22 to be in the most flexible state.

  With reference now to FIGS. 12A-12D, an alternative embodiment of a fail-safe tensioning mechanism is described, wherein multiple pulleys of previous embodiments have been replaced with a single pulley manifold. In FIG. 12A, a first embodiment of a pulley manifold is described. The pulley manifold 110 includes a main body 111, a first groove 113 a and a second groove 113 b, and a yoke 115, and the main body 111 has a central hole 112 that accommodates the colon 10, The groove 113a and the second groove 113b each receive a tension wire and are rolled or molded to the side surface 114 of the body 111, and the yoke 115 provides a pulley manifold 110 to the actuator (not shown). ).

  The first groove 113 comprises a curved passage that terminates at a first distal end 116 a that is disposed diametrically opposite the distal surface 117. The second groove 113b also includes a curved passage that intersects the first groove 113a at the intersection 118 and terminates at the second distal end 116b. The second distal end 116b is disposed on a distal surface 117 that is diametrically opposite (preferably 45 °) from the first distal end 116a. Similar to the distal pulley 87 of FIG. 10B, each groove receives a tension wire that extends the lumen into the overtube 22 through a diametrically disposed tension wire. To reduce the friction between the tension wires 90a and 90b at the intersection 118, the first groove 113a may have a deeper depth than the second groove 113b, or vice versa. . A sleeve (not shown) may be placed around the pulley manifold 110 to prevent the tension wire 90 from coming out of the groove 113.

  If the tension wire 90 comprises two separate length wires, the risk of reconfiguration of the overtube 22 if one of the wires breaks is reduced. This is because the tension in the overtube is symmetrically balanced as defined by the unbroken tension wire. If the remaining tension wire breaks, the overtube loosens and becomes flexible. If the tension wire 90 comprises a single length of wire, if the single wire breaks, the overtube will immediately loosen to a flexible state. Accordingly, the pulley manifold 110 provides the overtube 22 with a fail-safe mode that reduces the risk of overtube reconfiguration in the event of a tension mechanism failure.

  FIG. 12B shows a pulley manifold 110 where the yoke has been replaced by a third groove 120. The third groove 120 receives an additional tension wire 121 that can be rolled or molded into the side surface 114 and coupled to the actuator 27 (see FIG. 2). When a proximal force F is applied to the tension wire 121, this force tensions the tension wire 90. The third groove 120 includes a curved passage that terminates at the third distal end 122, which is preferably disposed diametrically opposite each other at the proximal surface 123 of the pulley manifold 110.

  With reference to FIGS. 12A and 12B, an alternative embodiment of a pulley manifold is described. Rather than having a groove disposed on the side surface of the pulley manifold, the pulley manifold 130 incorporates a first groove 131a and a second groove 131b that terminate in a tension wire hole 132 disposed through the body 133. Preferably, the tension wire holes 132 are disposed equidistantly and circumferentially on the proximal surface 136. The pulley manifold 130 also incorporates a central bore 134 that houses the colon 10 and a yoke 135 that couples the pulley manifold 130 to the actuator 27 (see FIG. 2).

  In FIG. 12C, the first groove 131a and the second groove 131b are rolled or formed in an overlapping manner, and the first groove 131a is reduced to reduce friction between tension wires disposed in the overlapping portions of the grooves. , May have a deeper depth than the second groove 131b, or vice versa. In FIG. 12D, the first and second grooves do not overlap, and the first groove 131a has a smaller radius of curvature than the second groove 131b.

  Applicants also note that either the first or second groove of the pulley manifold of FIGS. 12A-12D, the proximal force F applied thereto extends through a diametrically disposed tension wire lumen. It is contemplated that a single length of tension wire 90 can be eliminated to provide a symmetrical compression clamping force to overtube 22. Thus, if the tension wire 90 or 121 breaks or the yoke 115 fails, the overtube loosens and returns to its flexible state, thereby reducing the risk of undesirable reconfiguration of the overtube.

  Referring now to FIGS. 13A and 13B, a handle 21 employing the pulley manifold 110 of FIG. 12B will be described. Handle 140 from tension wire 90 in over-tube 22, skin 45, liner (not shown for illustrative purposes), and distal region 23 (see FIG. 2) through over-tube 22 The lumen 25 extending to (preferably less than or equal to 5 inches) is similar to the other handle embodiments described herein. Within handle 140, a tension wire is slidably coupled to pulley manifold 110, which spans cylindrical extension 141 and cylinder 142. Cylindrical extension 141 may be manufactured integrally with housing 143 and is configured to be inserted into the patient's rectum. Coaxial with the cylindrical expansion portion 141, the cylinder 142 defines a proximal portion of the lumen 25 that is disposed within the handle 140.

  Via an additional tension wire 121, the pulley manifold 110 is coupled to the slide block 92 and is adapted to move in the passage 93. Like handle 91 of FIG. 11, plunger 95 is pivotally coupled to slide block 92 at the proximal end and is slidably disposed within plunger housing 96 at the distal end. When arranged coaxially around the plunger 95, the compression spring 98 tilts the hand grip 97 from the operating state without applying a force from the outside. As in FIG. 11, the compression spring 98 maintains the tension level in the tension wire 90 when the adjacent telescoping element moves slightly when the overtube 22 is in a rigid state, thereby overloading. Reduce the risk of reconstitution returning to the flexible state of the tube.

  The handgrip 97 also includes pawls 99 configured to engage the teeth 144 of the ratchet bar 145 to prevent distal movement of the slide block 92. The teeth 144 are ratchet bars in a predetermined proximal position to allow a single actuation of the handgrip 97 that completely moves the overtube 22 from its flexible state to a fixed shape. 145. The ratchet bar 145 is pivotally mounted within the housing 143 with a spring (not shown) that tilts the pawl 99 with respect to the tooth 144 with the aid of a compression spring 98. To release the tension from the tension wire 90, the pawl 99 can be released from engagement with the tooth 144 by rotating the ratchet bar 145 proximally. This sufficiently relaxes the tension wire 90 so that the tension wire retains little or no tension, thereby allowing the overtube 22 to be in its most flexible state. To do.

  The handle 140 also has a shield 146 coupled to its distal end. The shield 146 prevents the handle 140 from being inadvertently inserted into the patient's rectum proximally. The handle 140 also incorporates an indicator 147 (FIG. 13B) that provides the clinician with information about the stiffness of the overtube 22. Indicator 147 includes a slot 148 disposed through the wall of housing 143, a pointer 149 disposed through slot 148, and a scale 150 disposed on the outer surface of housing 143 proximate to slot 148. . The pointer 149 is interlocked with the movement of the proximal manifold 110 and consequently moves with the manifold. The scale 150 incorporates a color gradation or indicia (not shown) indicating the stiffness of the overtube 22. Of course, it will be apparent to those skilled in the art that the pointer 149 can be associated with any structure in the handle 140 that moves when the actuator 27 is actuated (eg, the slide block 92 or pawl 99). Alternatively, the handle 140 may comprise a force sensor coupled between the distal end of the passage 93 and the slide block 92.

  Any of the handle embodiments described herein may also have a cylindrical extension 141 for insertion into the patient's rectum, the overtube from a flexible state to a rigid state with a single actuation of the actuator 27. One tooth 144 on the ratchet bar to convert to, a shield 146 to prevent insertion of the handle into the patient's rectum, an indicator 147 to provide the clinician with information about the stiffness of the overtube, and It will also be apparent to those skilled in the art that these combinations can be incorporated.

  With reference now to FIGS. 14A-14C, yet another alternative embodiment of a tensioning mechanism suitable for use with the apparatus of the present invention will be described. The handle 160 is adapted to reconfigure the overtube between its flexible and rigid states by continuous actuation of the actuator 27. The handle 160 has a housing 161 that includes a plurality of fixed columns 162 disposed circumferentially and azimuthally around an inner cylindrical chamber 163 of the housing 161. Each of the fixed posts 162 has a chamfered recess 164 disposed at the proximal end of the adjacent chamfered arm 165. A channel 166 is disposed between adjacent columns 162.

  The handle 160 also incorporates a proximally disposed compression spring 167 to tilt the pivotally attached manifold 168 relative to the plurality of posts 162. Manifold 168 has a chamfered distal end 170 and incorporates a plurality of distally projecting posts 169 having chamfered recesses 164 and mounting angles that match those of chamfered 165. . Thus, when the chamfered distal end 170 is strongly engaged with the chamfered recess 164, the force element applied by the post 169 is not present in the chamfered arm 165 and the manifold 168. Swivel. Similarly, when the chamfered distal end is engaged with the chamfered arm 165, the component of the force applied by the post 169 causes the manifold to pivot so that the column 162 is channel 166. At the proximal end.

  A tension spring 171 is also attached to the manifold 168, which in turn is preferably coupled to one of the pulley systems of FIGS. 10A-10C or 12A-12D. When the overtube is stiffened, the tension spring 171 maintains the tension wire 90 with a constant tension if the telescoping element disposed within the overtube moves slightly. This therefore reduces the risk of reconfiguration of the overtube to a flexible state that would otherwise occur in the absence of the tension spring 171.

  The handle 160 further includes a movable cylindrical collar 172 having teeth 173 projecting proximally. Each tooth has a mounting angle that is substantially equivalent to that of the chamfered distal end 170 of the manifold 168. Thus, when the tooth 173 is strongly engaged with the chamfered distal end 170, the component of the force applied by the tooth causes the manifold to pivot. Actuators 27 (exemplarily movable handgrip 174) are also coupled to collar 172, which are squeezed against stationary handgrip 175, retracting collar 172 proximally and manifold 168. The chamfered distal end 170 is contacted.

  FIG. 14B shows the configuration of the handle 160 when the overtube connected thereto is in a rigid state. The chamfered distal end 170 of the manifold 168 is engaged within the recess 164 of the post 162. If it is desired to reconfigure the overtube to its flexible state, the movable handgrip 174 is squeezed against the stationary handgrip 175. This action moves the collar 172 in the proximal direction. When the teeth 173 engage the chamfered distal end 170, the continuous proximal advancement of the movable handgrip 174 causes the collar to move the manifold 168 proximally relative to the compression spring 167. Press to. When the chamfered distal end 170 removes the chamfered arm 165, the force applied to the chamfered distal end by the teeth 173 pivots the manifold 168 as shown in FIG. 14B. As a result, the chamfered distal end 170 is engaged with the chamfered arm 165.

  Retraction of the collar 172 releases the teeth 173 from the manifold 168. The force applied to the chamfered distal end by the chamfered arm 165 causes the manifold 168 to pivot until the chamfered distal end removes the column 162. Thereafter, the bias of the compression spring 167 advances the plurality of posts 169 into the channel 166. FIG. 14C shows the configuration with the overtube in its flexible state.

  The movable handgrip 174 is again squeezed against the stationary handgrip 175 to reconfigure the overtube back to its rigid state. This advances the collar 172 proximally until the teeth 173 contact the chamfered distal end 170 of the post 169. The continuous proximal actuation of the movable hand grip 174 causes the collar 172 to push the post 169 out of the channel 166. When the chamfered distal end 170 removes the column 162, the force applied to the chamfered distal end 170 by the teeth 173 causes the manifold 168 to pivot. Retraction of the collar 172 releases the teeth 173 from the manifold 168 and the bias of the compression spring 167 advances the manifold 168 until the chamfered distal end 170 fully engages the recess 164.

  With reference now to FIG. 15, yet another alternative embodiment of a handle 21 suitable for use with the apparatus of the present invention is described. The handle 180 includes a housing 181 that includes an overtube lumen 25. The handle 180 further includes a piston 182 movably disposed within the piston housing 183, which is connected in air communication via a tube 185 that includes a port 184 and a pressure source (not shown). A pulley 187 is mounted on the piston shaft 186 and a proximal tension wire 188 is disposed thereabout. Proximal tension wire 188 is secured to housing 181 at its proximal end 189 and to tension spring 190 at its distal end. Preferably, the tension spring 190 is distally coupled to one of the pulley systems of FIGS. 10A-10C or 12A-12D. Similar to the tension spring 171 of FIGS. 14A-14C and the compression spring 98 of FIGS. 11 and 13, the tension spring 190 maintains the tension wire at a constant tension when the overtube is in a fixed shape. This reduces the risk of reconfiguration of the overtube into its flexible state if the telescoping element disposed therein moves slightly relative to the adjacent telescoping element.

  In order to stiffen the overtube, a pressure source can be activated to inject pressurized air into the piston housing 183 and advance the piston 182 proximally. This then advances the pulley 187 in the proximal direction so that tension is applied to the proximal tension wire 188. The tension is transmitted via a tension spring 190 to a tension wire placed in the overtube, thereby pressing the compression clamp load against an adjacent telescoping element placed in the overtube. A pressure source may be activated to remove air from the piston housing 183 in order to move the fixed shape overtube to a flexible state. This retracts the piston 182 and pulley 183 distally, thereby releasing the compression clamp load applied to the overtube.

  In accordance with another aspect of the present invention, the tension spring 190 can be replaced with a damper known per se in the art. In addition to the advantages provided by tension springs, the damper allows tension in the proximal tension wire 188 so that the tension wire placed in the overtube is released slowly. Applicant intends that the damper may replace any of the compression springs and tension springs described herein.

  Referring now to FIG. 16, the device 20 is selective for the transition of the overtube 22 between a flexible state and a rigid state, with substantially no proximal movement of the distal region 23. Can be equipped with a tensioning mechanism that can be actuated (see FIG. 2). In FIG. 16, tension wire 196 and lumen 25 extend from distal region 23 through overtube 22 to handle 195. Within the handle 195, a tension wire 196 is slidably coupled to the pulley manifold 197, which is rigidly or pivotally secured to the distal end of the handle. The pulley manifold 197 preferably comprises a first channel 199a and a second channel 199b that are arranged orthogonally. Although FIG. 16 shows only one tension wire, it should be understood that the second tension wire is preferably disposed through the second channel 199b and the telescoping element 30. FIG.

  Similar to the tension mechanism of FIGS. 12A-12D and 13, the tension mechanism of the present invention also provides an overtube 22 with a fail-safe mode. If the tension wire placed through channel 199 comprises two independent wires, the load in overtube 22 remains symmetrically distributed when one of the wires breaks. Therefore, the risk of reconfiguration of the overtube 22 is reduced. If these tension wires comprise a single length of wire, the overtube 22 relaxes to a flexible state when the single length of wire breaks.

  Between the pulley 197 and the telescoping element 30, the tension wire 196 also extends through the collar 200 and the collar 200 opposes to mate with the proximal surface 32 of the most proximal telescoping element 30. And has a distal surface 201 that is continuous. The collar 200 is arranged to move within the housing 202 so that the collar 200 engages the proximal surface 32 of the telescoping element 30 when advanced in the distal direction.

  The collar 200 is pivotally connected to the plunger 95, which is slidably disposed on the plunger housing 96. Next, the plunger housing 96 is pivotally attached to the actuator 27 (exemplarily hand grip 97). In order to tilt the handgrip 97 against actuation with no externally applied force and to maintain a constant tension in the tension wire 196 when the overtube 22 becomes stiff, a compression spring 98 is provided for the plunger 95. Are provided to be arranged coaxially around.

  The handgrip 97 also includes pawls 99 that are arranged to engage the teeth 100 on the ratchet bar 101 to prevent proximal movement of the collar 200. The ratchet bar 101 is pivotally mounted within the housing 202 with a spring (not shown) that tilts the pawl 99 with respect to the teeth 100 of the ratchet bar 101 with the aid of a compression spring 98. The handle 195 can also incorporate an annular extension 203 that can be placed around the collar 200 and inserted into the patient's rectum.

  Similar to the operation of the handle 91 of FIG. 11, when the hand grip 97 is squeezed, the pawl 99 engages the adjacent most distal tooth 100. This action also transmits force through the compression spring 98 and pushes the collar 200 into engagement with the most proximal telescoping element. The continuous actuation of the handgrip 97 causes the collar 200 to exert a progressively increasing compression clamp load on the telescoping element 30 and stiffens the overtube 22 to a fixed shape.

  Advantageously, this arrangement allows the overtube 22 to reconfigure between a flexible state and a rigid state without substantially proximal movement of the distal end of the overtube. To do. In previous embodiments, the telescoping element 30 is advanced proximally when the overtube 22 becomes stiff, and the overtube 22 shortens its length due to compression of the adjacent telescoping element. . In contrast, when an embodiment of the present invention advances a telescoping element in the distal direction, overtube 22 maintains its length despite the compression of adjacent telescoping elements. This is because the length of the overtube is substantially limited by the length of the tension wire 196. This provides better accuracy when using the apparatus of the present invention and is particularly useful in delicate procedures.

  It will be apparent to those skilled in the art that the ratchet bar 101 can be provided with only one tooth, similar to the tension mechanism described with reference to FIG. Alternatively, with slight modifications apparent to those skilled in the art, the tension system of FIGS. 14A-14C can be coupled to the collar 200 and overrun between the flexible and rigid states by continuous actuation of the actuator 27. The tube 22 can be moved, or the piston mechanism described with reference to FIG. 15 can be coupled to the collar 200 to drive its movement. More specifically, rather than being pivotally connected to the plunger 95, the collar 200 may instead be secured to a piston that is arranged to provide movement along the longitudinal axis of the collar 200. Further, the second channel 199b is excluded from the pulley manifold 197 so that a single tension wire can be movably extended through the first channel 199a and the collar 200 and telescopic element 30 The tension wire holes disposed therein may be disposed opposite to each other. If a single tension wire breaks, the overtube immediately relaxes to a flexible state, thereby providing a fail-safe mode that reduces the risk of undesired reconfiguration of the overtube.

  With reference to FIGS. 17A and 17B, an alternative structure for facilitating colonic movement within lumen 25 of overtube 22 is described. In particular, instead of using the inner lining 43 as illustrated in FIG. 4, some or all of the telescoping elements 30 are received in an inset 206 formed in the telescoping element 30. Can be provided. The bearing 205 may be disposed on the ring 207 to facilitate device assembly.

  18A and 18B illustrate a further alternative embodiment, in which a lubricious flexible rail 208 is disposed within the bore 33 of the telescoping element 30. FIG. The rail 208 reduces the contact between the colon and the inside of the overtube over the length of the lumen 25, thereby facilitating colon movement through the overtube.

  19 and 20, a still further alternative structure for facilitating colon movement within lumen 25 of overtube 22 is described. More specifically, rather than using the liner 43 shown in FIG. 4, some or all of the telescoping elements 30 may incorporate a hydrophobic coated polymer layer 209 that is distal to the hole 33. A portion 210 may be disposed around.

  Alternatively, as described in FIGS. 20A and 20B, the overtube 22 comprises a plurality of frustoconical elements 215 that, when nested, provide a smooth inner lumen and are separate. The colon 10 is housed without the need for a liner. Each frustoconical element 215 includes a central hole 216 and at least two or more tension wire holes 217. The central bore 216 is defined by a cylindrical distal inner surface 218 that has a substantially constant diameter and a proximal inner surface 219 that is continuous with the distal inner surface 218.

  The proximal inner surface 219 is slightly curved in the radially outward direction so that when the tension wire 36 is relaxed, the proximal inner surface 219 is in relation to the outer surface 220 of the adjacent element. Can turn. The outer surface 220 of each frustoconical element conforms to the shape of the proximal inner surface 219 along a straight line or contour, and the distal end 221 is smaller than the outer periphery of the proximal end 222 Thus, each element is tapered. When the frustoconical elements 215 are nested together, the distal inner surface 218 of each frustoconical element is disposed adjacent to the distal inner surface of the adjacent frustoconical element.

  Advantageously, the configuration of the present invention provides a lumen 25 having a substantially continuous profile. This allows a smooth progression of the colon 10 therethrough, thereby eliminating the need to place a separate liner within the lumen 25. In order to provide a lubrication path to further facilitate colonic progression, each frustoconical element is optionally integrated into a polymer as described with respect to the previous embodiment of FIG. A lining can be incorporated, or a thin and flexible lining with a hydrophilic coating can be placed through the lumen 25.

  In FIGS. 21A-21C, yet another alternative structure is described where the distal surface 31 of each telescoping element is macroscopically textured when a compression clamp load is applied to the overtube 22. Thus, the friction between adjacent telescoping elements 30 is increased. Illustratively, each element 30 may incorporate a plurality of divots 225 and teeth 226 disposed on the distal surface 31, which teeth 226 are disposed on the proximal surface 32 adjacent to the proximal edge 227. . The teeth 226 are contoured to mate with a plurality of divots located on adjacent elements. Thus, when the overtube 22 is tensioned, the retraction of the tension wire 36 (see FIG. 3) applies a clamping load to the element 30 which causes each element's teeth 226 to be adjacent element's teeth 226. The divot 225 is strongly engaged. This reduces the risk of relative angular movement between adjacent telescoping elements 30 when the overtube 22 is fixed in shape, and then reduces the risk of undesired reconfiguration of the overtube. .

  One or more plates when the overtube 22 is in a flexible state to prevent the divot 225 and teeth 226 from engaging, and thus to provide each smooth transition between adjacent elements 30. A spring 228 may be integrally formed with the proximal surface 32. Thus, without the compression clamp load applied by the tension wire 36, the overtube 22 becomes stiff and the leaf springs 228 of each element 30 come into contact with the distal surface of the adjacent element so that the proximal surface 32 and the distal surface 31 is prevented from engaging the tooth 226 with the divot 225.

  Alternatively, rather than having a leaf spring, the telescoping element 30 may be provided with one or more cantilever springs 229, which are cut from the wall 34 and plastically inserted into the holes 33 of the telescoping element 30. Bend. Like the leaf spring 228, the cantilever spring 229 prevents forcing between the distal surface 31 and the proximal surface 32 so that the teeth 226 engage with the divot 225 in the absence of a compression clamp load. Do not match. The cantilever spring 229 can be aligned with the longitudinal axis of the telescoping element 30 as shown in FIG. 21B and / or can be aligned with the outer periphery of the telescoping element 30 as shown in FIG. 21C. Applicant also contemplates that the teeth 226 may be disposed on the distal surface 31 and the divot 225 may be disposed on the proximal surface 32. Those skilled in the art will recognize additional macroscopic textures that increase the friction between the distal and proximal surfaces of adjacent elements 30.

  On the other hand, instead of providing a cantilever spring leaf integral with the telescoping element 30, a thin flexible disk 232 (FIG. 21D) is placed between adjacent telescoping elements 30 to provide a divot 225. (See FIGS. 21A-21C) and adjacent element teeth 226 may be prevented from engaging in the absence of a compression clamp load. Each disk 232 incorporates a central hole 233 that houses the colon and is made of an elastomeric material. For illustrative purposes, the telescoping element 30 and the disk 232 are shown spaced apart, but the element and disk are discs with the distal surface 31 of one element 30 and the proximal surface 32 of an adjacent element being a disk. It should be understood that it is placed in contact with H.232 (placed between them). It should also be understood that each telescoping element 30 also includes a tension wire hole, which is not shown in FIGS. 21A-21D for illustrative purposes.

  In accordance with one aspect of the present invention, the telescoping element 30 can also incorporate a band 231 that is disposed distally adjacent to the proximal edge 227. The band 231 increases the heat in the proximal portion of the wall 34 and distributes the applied compression clamp load across a large cross-sectional area, thereby reducing the radially outward bending deflection of the wall 34. This in turn reduces the longitudinal contraction of the overtube 22. The band 231 is preferably made of metal to provide good structural integrity to the wall 34, but can also be integral.

  In accordance with another aspect of the present invention, the diameter of the lumen 25 is configured to facilitate simultaneous passage of one or more diagnostic or therapeutic devices therethrough. As shown in FIG. 22, the lumen 25 is dimensioned to allow the auxiliary device AD (eg, for inhalation, for biopsy, or for further illumination) to be advanced in parallel with the colon 10. Can be decided. For example, if the lumen 25 has a diameter of 13 mm and the colon 10 has a circumference of 10 mm, an auxiliary device AD (e.g., a catheter) having a diameter between 3F and 9F may be used for the remainder of the lumen 25. Can be advanced through space. Advantageously, this means that the auxiliary device AD is placed continuously in the patient's colon to perform further diagnostic or therapeutic procedures without having to remove the colon 10 and overtube 22 therefrom. Enable.

  With reference to FIG. 23, an alternative embodiment of a distal region suitable for use in the overtube of the present invention will be described. The distal region 235 is constructed similarly to the distal region 23 of the embodiment of FIG. 4 but has a flexible coil 236 that is embedded only in the proximal portion of the elastomeric layer 237. The atraumatic tip 238 at the distal end of the distal region 235 may further enhance the maneuverability of the overtube 22 when the colon steerable tip is placed therein.

  FIGS. 24-28 illustrate further arrangements of atraumatic tips that are suitable for producing “tenting” of the walls of hollow body organs. As used herein, tenting refers to the tendency of the atraumatic tip to be deflected radially outward near the tip of the overtube. This reduces the risk that the wall of the organ will be pinched or caught between the colon and the entrance of the overtube 22 when the colon is retracted into the overtube.

  FIG. 24A shows an atraumatic tip 24 in the form of an inflatable donut-shaped balloon 240 secured to the distal region 23 to the overtube 22. An inflation lumen 241 extends from the handle through the overtube 22 and provides fluid communication between the balloon 240 and an inflation source (eg, a syringe (not shown)). As illustrated in FIG. 24B, when the balloon 240 is inflated, the wall of the colon deflects radially around the balloon 240. Thus, when the colon 10 is contracted within the lumen 25, the colon wall is less likely to be pinched or severely torn between the overtube 22 and the colon. Further, when inflated, the balloon 240 closes the annular gap 242 disposed between the wall of the overtube 22 and the colon 10 to prevent bodily fluids and other materials from entering the lumen 25. Advantageously, the balloon 240 provides a special fit around the colon 10.

  FIG. 25 illustrates a further alternative embodiment of the atraumatic tip 24 with a soft membrane 245 covering the shape memory alloy petal 246. Petal 246 preferably comprises a loop of shape memory alloy wire (eg, nickel titanium alloy) and extends radially outward into lumen 25 proximally near the distal opening, As a result, the proximal end of the membrane covering the petal produces the “tenting” effect described hereinabove. When exposed to body temperature, this shape memory alloy can be activated to incorporate a pre-formed shape and returned to a contracted state by flushing the overtube 22 with cold water or air. Alternatively, the petal 246 can be mechanically extended, contracted, or self-expanded.

  FIG. 26 illustrates a further alternative embodiment of the atraumatic tip 24. In the embodiment of FIG. 26, a petal 250 covered by a soft elastomeric membrane 251 extends distally from the distal region 23 to form a funnel-shaped element 252. The atraumatic tip 24 provides the same tenting effect as described for the previous embodiment.

  27-28 provide a further alternative configuration for the atraumatic tip 86 of the embodiment of FIG. The tip 255 preferably comprises a foamed elastomer or a soft elastomer and can be secured to the distal region 23 of the overtube 22 using a suitable biocompatible adhesive. FIG. 28 illustrates an alternative shape for a foamed elastomeric bumper or a soft elastomeric bumper 260, which includes a flange 261 that extends proximally. Of course, those skilled in the art can use other configurations in accordance with the principles of the present invention to form atraumatic tips that result in local tenting of the colon wall, and these atraumatic tips can be It will be appreciated that it can be used with the passively steerable distal region of the embodiment of FIGS.

  Referring now to FIGS. 29 and 30, an alternative embodiment of an overtube is described. Unlike the previously described embodiment overtube 22 where the mechanical mechanism is actuated to provide a clamping load to multiple telescoping elements, the embodiment of FIGS. 29 and 30 uses an alternative tension mechanism. . In particular, the following embodiments comprise a number of connections where the compression clamp load can be applied by contraction of the shape memory material.

  In FIG. 29, a first alternative embodiment of the overtube of the present invention is described. Overtube 270 includes a number of telescoping elements 30 similar to those described above. For illustrative purposes, the telescoping elements 30 are shown spaced apart, but the elements 30 are arranged such that the distal surface 31 of each element 30 covers the proximal surface 32 of an adjacent element. It should be understood. Each telescoping element 30 has a central hole 33 for receiving the colonoscope 10, preferably two or more tension wire holes 35. When assembled as shown in FIG. 29, the telescoping element 30 is fastened with a distal surface 31 and a proximal surface 32 that are arranged in a contacted manner by a plurality of tension wires 271 extending through the tension wire holes 35. .

  In contrast to the overtube 22 of the previous embodiment, the overtube tension wire 271 of the present invention is made from a shape memory material (e.g., nickel titanium alloy or electroactive polymer) known in the art. The tension wire 271 is fixedly connected to the distal end of the overtube 270 at its distal end and fixedly connected to the handle 21 at its proximal end. When current passes through the tension wire 271, the length of the wire contracts and exerts a compression clamp load, which loads the distal surface 31 and the proximal surface 32 of the telescoping element 30 together with the current relative orientation. To fix the shape of the overtube 270. When the application of electrical energy is interrupted, the tension wire 271 stretches again in its length to provide relative angular movement between the telescoping elements 30. This then makes the overtube 270 sufficiently flexible to pass through the serpentine passage through the colon.

  In order to provide the overtube 270 with a fail-safe mode that reduces the risk of unwanted reconfiguration of the overtube in the event of a tension mechanism failure, diametrically arranged tension wires 271 may be connected in series. Thus, if one wire fails, the diametrically placed wire will also stretch again to maintain a contrasting clamp load in the overtube 270. Alternatively, all tension wires 271 can be electrically connected in a series electrical circuit. Thus, if one of the tension wires fails, the overtube 270 returns to the flexible state.

  It should be understood that a tension spring (not shown) or damper (not shown) similar to those described herein above can be coupled between the proximal end of the tension wire 271 and the handle 21. Yes (see Figure 2). In particular, this maintains the tension wire with a constant tension when the overtube is in a fixed shape, so that the telescoping element placed therein has moved slightly relative to the adjacent telescoping element If this is the case, the risk of this overtube reconfiguring into its flexible state is reduced.

  Alternatively, as shown in FIG. 30, the overtube 280 may include a number of nested elements 281 similar to the previous embodiment. For illustrative purposes, the telescoping elements 281 are shown spaced apart, but the elements 281 are positioned such that the distal surface 282 of each element 280 covers the proximal surface 283 of the adjacent element. Should be understood. Each telescoping element 280 has a central hole 284 for receiving the colonoscope 10.

  When assembled as shown in FIG. 30, the telescoping element 280 is disposed in a contacted manner by a plurality of thin tension ribbons 285 fixedly coupled to the telescoping bridging element 286 and proximal Fastened with surface 283. The tension ribbon 285 is made from a shape memory material (e.g., nickel titanium alloy or electroactive polymer) and can transition from an equilibrium length to a contraction length when current is passed through it.

  Nested bridging elements 286 are disposed in the overtube 280 between a predetermined number of nested elements 281. Like the telescoping element 281, the bridging element 286 also includes a central hole 287 that houses the colonoscope 10, a distal surface 288 that contacts the proximal surface 283 of the distally adjacent telescoping element, and a proximally adjacent A proximal surface 289 that contacts the distal surface 282 of the nested element 281. Each bridging element also incorporates a plurality of conductive elements 290, which are arranged by azimuth around the central hole 287, and preferably at the same angular peripheral location in the overtube 280 through the series electrical circuit The tension ribbon 285 occupying is connected.

  When current passes through the tension ribbon 285, the length of the ribbon contracts, providing a compressive load that anchors the distal and proximal surfaces of adjacent telescoping elements together in the current relative orientation, thereby The shape of the overtube 280 is fixed. If the energy source interrupts the supply of electricity, the tension ribbon 285 again stretches to its equilibrium length, providing relative angular motion between the telescoping elements. This in turn makes the overtube 280 sufficiently flexible to pass through a serpentine path through the colon.

  According to another aspect of the present invention, the tension ribbons 285 disposed diametrically at the surrounding locations can be electrically connected in a series circuit. Advantageously, this configuration provides the overtube 280 with a fail-safe mode that reduces the risk of unwanted reconfiguration of the overtube when power is not supplied to one of the electrical circuits established through the tension ribbon.

For example, the overtube 280 of FIG. 30 may comprise four sets of tension ribbons that are equidistantly spaced at 90 ° intervals. When power to the tension ribbons T _a is not supplied, i.e., the tension ribbons T _a, when there is no electrical contact between the tension ribbons T _c disposed on the opposite side, the overtube 280 is naturally a new Reconfigure to a hard shape. This is because the tension in the overtube is no longer symmetrically balanced. This new shape of the overtube 280 does not replicate the serpentine path of the colon and therefore cannot cause substantial harm to the patient.

Advantageously, the present invention may reduce the risk of unwanted reconfiguration, preferably by electrically connecting diametrically arranged tension ribbons in a series circuit. When power to the tension ribbons T _a is not supplied, the tension ribbons T _c is also not supplied power, providing contrasting tension overtube 280, to tension wires T _b and tension wires arranged in the opposite Similarly, contrasting tension is provided (not shown). Thus, the overtube maintains its desired rigid shape when the tension mechanism is activated. If no tension ribbon is powered, all ribbons 285 can be electrically connected in a series circuit to immediately return the overtube 280 to its flexible state.

  In an alternative embodiment, the tension ribbon 285 can be electrically connected to stiffen selected areas of the overtube without stiffening the remainder of the overtube. Illustratively, this can be accomplished by connecting longitudinally adjacent tension ribbons in a parallel circuit and peripherally adjacent tension ribbons in a series circuit.

  Of course, although FIG. 30 shows a tension ribbon 285 disposed within the central holes 284 and 287, it will be apparent to those skilled in the art that the tension ribbon can also be disposed on the adjacent outer surface 292 of the telescoping elements 281 and 286. is there. Alternatively, the tension ribbon can extend through tension ribbon holes (not shown) that can extend through the distal and proximal surfaces of the telescoping element 281 and can be attached to the telescoping bridging element 286.

  31-37, an alternative embodiment of overtube 22 is described. Unlike the overtube 22 of the above embodiment that includes multiple telescoping elements that are fastened with multiple tension wires or ribbons, the embodiment of FIGS. 31-37 uses an alternative tension mechanism. In particular, the following embodiments include a plurality of links that may be stiffened through the use of a compression sleeve that includes individual links disposed along the length of the overtube.

  Referring now to FIGS. 31A-31C, a fourth alternative embodiment of the overtube of the present invention will be described. The overtube 300 includes a plurality of spool links 301 and clamp links 302 alternately. Each of the spool link 301 and clamp link 302 has a hole disposed therethrough to accommodate a standard colonoscope. The spool link 301 includes rounded ends 303 disposed at its distal and proximal ends, and these distal and proximal ends are contoured to be disposed within the holes in the clamp link 302. Contoured to allow limited rotatable engagement with one of the two grooves 304 formed. Accordingly, the clamp link 302 has a larger outer diameter than the spool link 301. Each clamp link 302 also has a longitudinally disposed penetration to allow a decrease in the diameter of the clamp link 302 when the clamp link is compressed, as discussed herein below. It has a wall spool link 305.

  Still referring to FIGS. 31A-31C, a first embodiment of a compression sleeve comprises an expandable sleeve 310 having a first compression portion 311 and a second compression portion 312. The sleeve 310 is configured such that the inner diameter of the second compression portion 312 is smaller than the inner diameter of the first compression portion 311 when the sleeve 310 is expanded. The second compression portion 312 can be arranged to engage the clamp link 302. Thus, when the expandable sleeve 310 is expanded by an expansion source (not shown) coupled to the handle, the second compression portion 312 compresses the clamp link 202 into the fixed overtube 300 in shape. To do. In FIGS. 31B and 31C, cross-sectional views of the first compressed portion 311 and the second compressed portion 312 are shown with the sleeve 310 in its expanded state, respectively.

  FIG. 32 shows an alternative embodiment of a compression sleeve that also includes an expandable bag. Unlike the expandable bag of FIGS. 31A-31C, the helical bag 320 has a constant inner diameter. The helical bag 320 is preferably arranged helically around the overtube. Accordingly, when the bag 320 is expanded, the clamp link 302 is compressed against the spool link 301 to harden the overtube.

  FIG. 33 illustrates a further embodiment of a compression sleeve 330 that includes a discontinuous hoop 331 made from a shape memory alloy (eg, a nickel titanium alloy). Each hoop 331 includes a groove portion 332, and this groove portion 332 is bridged by a spring 333. Each hoop 331 is electrically connected to an adjacent hoop 331 via an insulated wire 334, thereby establishing a series electrical circuit. When power is supplied to the hoop 331, these hoops undergo a phase transition, which can cause the hoop to contract into a preformed shape that is smaller in size than the unpowered shape. Since the hoop 331 can be placed around the clamp link 302, the contraction of the hoop 331 can be used to provide a clamp load that compresses the link 302 toward the spool link 301 and stiffens the overtube.

  When the hoop 331 is not powered, the spring 333 contributes to structural integrity. Current can flow through wire 334 to provide power and thereby cause hoop 331 to contract. Cold water or cold air may be flowed through the hoop 331 to return the hoop 331 to its uncontracted state, thereby returning the overtube to its flexible state. Of course, those skilled in the art will understand that the hoop 331 is also powered separately and therefore requires a parallel circuit.

  34A-34B, still further alternative embodiments of overtubes suitable for use in the present invention are described. This embodiment comprises a helical link 340 formed from a unitary strip 341 having different durometer regions (eg, rigid material 342 and soft material 343). When the strip 341 is spirally wound, a spiral link 340 having a rigid portion 344 and a soft portion 345 is formed. Rigid portion 344 provides structural integrity to the overtube, while soft portion 345 provides flexibility.

  Helical link 340 is disposed within compression sleeve 346, which includes a first compression portion 347 and a second compression portion 348. The compression sleeve 346 is as described in FIGS. 31A-31C except that the second compression portion 348 is aligned with the rigid portion 344 of the helical link 340 and provides a mooring force to the rigid portion 344. The structure and operation are the same. Of course, it will be appreciated that overtubes in accordance with the principles of the present invention may alternatively be formed from any of the mooring systems described with respect to FIGS. 32 and 33 using helical links 340.

  Referring now to FIG. 35, another alternative embodiment of an overtube is described, wherein each Grecian link 350 is a rigid body disposed at the longitudinally opposite end of the flexible body 353. A first rim 351 and a second rim 352 are provided. The first rim 351 includes a U-shaped arm 354 that defines a channel 355 and an opening 356. The second rim 352 includes a reversing arm 357 that, when engaged with the adjacent first rim 351, is disposed in the channel 355 of the U-shaped arm 354 through the opening 356, and as a result. , U-shaped arm 354 and reversing arm 357 engage and overlap along the longitudinal axis of the overtube.

  The Grecian link 350 is disposed within a compression sleeve 358 that includes a first compression portion 359 and a second compression portion 360. The compression sleeve 358 is other than that the second compression portion 360 is aligned with the U-shaped arm 354 and the reversing arm 357 overlying the first and second rims and imparts a mooring force to these arms. Are the same in structure and operation as described in FIGS. 31A and 34A. Of course, it will be appreciated that an overtube in accordance with the principles of the present invention may alternatively be formed from any of the mooring systems described with respect to FIGS. 32 and 33 using a Grecian link 350.

  Referring now to FIG. 36, yet another alternative embodiment of an overtube suitable for use in the present invention is described. This embodiment includes a joining link 370, which comprises a ball 371 and a socket 372 disposed at the ends of the flexible body 373 facing in the longitudinal axis direction. When adjacent joint links 370 are engaged, one link ball 371 is placed in the adjacent link socket 372. When the overtube is bent, the ball 371 contacts the socket 372 and provides an overtube joint.

  The junction link 370 is disposed within the compression sleeve 374, which includes a first compression portion 375 and a second compression portion 376. The compression sleeve 374 is similar to that shown in FIGS. 31A and 34A except that the second compression portion 376 is aligned with the socket 372 in which the ball 371 of the adjacent link is disposed and provides a mooring force to the socket 372. The structure and operation are the same as those described in FIGS. Of course, it will be appreciated that overtubes in accordance with the principles of the present invention may alternatively be formed from any of the mooring systems described with respect to FIGS. 32 and 33 using junction links 370.

  With reference to FIG. 37, a still further embodiment of an overtube suitable for use in the device of the present invention will be described. The overtube 380 is a thermosoftened polymer layer 381 having a wire 382 embedded therein (eg, Carbothane®, a proprietary urethane-based polymer available from Thermedics Polymer Products, Woburn, Ma). including. The wire 382 is coupled to an energy source at the handle so that sufficient resistance heating occurs to soften the polymer layer 381 by passing a current through the wire 382, causing the polymer layer to be serpentine or supported. Be flexible enough to pass through non-anatomical structures. If electrical energy is not supplied to the wire 382, neither resistance heating of the wire nor resistance heating of the polymer layer occurs, instead the overtube cools and hardens. Wire 382 serves the dual purpose of providing twist resistance and electrical heating.

  Still referring to FIG. 37, yet another alternative embodiment of an overtube suitable for use in the present invention includes a soft elastic polymer layer 381 having a shape memory alloy wire 382 embedded in the layer 381. In this embodiment, the shape memory alloy is selected to have a martensitic transition temperature above body temperature. For example, by passing a current through the alloy, it is heated to a temperature above body temperature, the wire transitions to the austenite phase and becomes harder, thereby fixing the shape of the overtube. When the application of current is stopped, the wire 382 cools back to the martensite phase, making the overtube flexible.

  38A-38C, a further alternative embodiment of an overtube suitable for use with the present invention will now be described. Overtube 390 includes an elongated body 391 having a central lumen 392 that houses colonoscope 10 and a wire lumen 393 defined by a cylindrical wire lumen surface 394. Within each wire lumen 393 is a wire 395 extending the length of the elongated body. The elongate body 391 is made from an electroactive polymer known in the art, which allows the wire lumen 393 to change its diameter in response to power supply.

  In particular, when current flows through the elongated body 391, the diameter of each wire lumen 393 decreases, so that the wire lumen tightens around the respective wire 395. Preferably, both wire 395 and wire lumen surface 394 are textured to increase the friction between them. This prevents further relative movement between the elongated body 391 and the wire 395 and makes the overtube 390 stiff. When the application of current is stopped, the diameter of the wire lumen 393 increases and releases the wire 395 so that the elongated body 391 can move relative to the wire 395. This then makes the overtube 390 sufficiently flexible to pass through a serpentine path through the colon.

  With reference to FIG. 39, yet another alternative embodiment of an overtube is described. Overtube 400 includes a number of variable diameter links 401 arranged in an overlapping manner around a number of rigid links 402, which provides the structural integrity of the overtube. Each link includes a central hole that defines an overtube lumen 25 and accommodates a standard commercial colonoscope. The variable diameter link 401 is preferably manufactured from an electroactive polymer or a shape memory alloy that shrinks in diameter when powered. When the variable diameter link 401 is electrically activated, the variable diameter link is tightened around the rigid link 402, causing the overtube 400 to transition to a fixed shape state. When the variable diameter link is electrically deactivated, the variable diameter link is sufficiently softened to return the overtube 400 to its flexible state.

  In a preferred embodiment, variable diameter links 401 and rigid links 402 are formed from respective material strips that are spirally wound in an overlapping manner to form overtube 400. Alternatively, each link can be formed separately and placed in an overlapping manner.

  In FIGS. 40A-40B, yet another alternative embodiment of an overtube suitable for use with the device of the present invention is shown schematically. Overtube 405 includes a number of constricted telescoping elements 406, which are preferably manufactured from an electroactive polymer or shape memory alloy and each connected by a neck 409. It has a spherical distal portion 407 and a proximal portion 408. The diameter of the neck 409 is less than the maximum diameter of the distal portion 407, which is also less than the maximum diameter of the proximal portion 408. The distal portion of the outer surface 410 of each constricted element 406 is contoured to cooperate with the proximal portion of the inner surface 411 of the distally constricted element. Thus, when multiple constricted elements are nested together to form an overtube 405, adjacent elements 406 can move more relative to each other when the overtube is in a flexible state.

  Proximal portion 408 includes a plurality of slits 412 disposed adjacent to proximal edge 413 to reduce friction between adjacent elements during relative motion between adjacent elements. The slits 412 also facilitate contraction of the proximal portion 408 of each element around the distal portion 407 of the adjacent element. Each constricted element 406 also has a central hole 414 that houses the colonoscope 10 (see FIG. 1).

  When current is applied to multiple constricted telescoping elements 406, the proximal portion 408 of each element contracts its diameter around the distal portion 407 of the adjacent element. The compression mooring force applied thereto prevents relative movement between adjacent elements, thereby fixing the overtube in shape. When the current supply to the telescoping element is turned off, the proximal portion 408 is loose enough to allow relative movement between adjacent telescoping elements 406, so that the overtube 405 is a serpentine curve. Allows to pass through. For illustrative purposes, the drawings of the present application may not show electrolytic wires, electrodes, and insulated wires that are coupled to promote ionization and thus shrinkage of the electroactive polymers described herein. Should be understood.

  According to another aspect of the present invention, the overtube of the present invention may comprise a disposable sheath 420 that may extend the length of the overtube 22 and be removed therefrom. Like the sheath described hereinabove with respect to FIG. 4, the sheath 420 of FIG. 41 is also encapsulated in a distally disposed atraumatic tip 421 and a flexible layer 423. A flexible torsion resistant coil 422 may be incorporated. At its proximal end, layer 423 is integrally formed with a lubricious liner 424 and a flexible elastic skin 427 that join or define a lumen 425. The liner 424 can incorporate any flexible torsion resistant coil 429, can be made from a thin flexible material, and / or has a hydrophilic coating similar to that described with respect to FIG. Can have. An annular chamber 428 is disposed between the liner 424 and the skin 247, into which the telescoping element 30 can be inserted. The sheath 420 is configured to slide over and out of the column of the telescoping element 30 so that the sheath can be discarded after a single use, while the telescoping element and handle are It can be sterilized and reused. Advantageously, significant cost savings can be realized.

  According to another aspect of the invention, apparatus 20 may further comprise a device for securing colonoscope 10 to apparatus 20 prior to insertion of apparatus 20 and colonoscope 10 into a patient. FIG. 42 shows a strap 430 that can be secured distally to the handle 21 of the device 20 and proximally to the proximal portion 13 of the colonoscope 10. The strap 430 preferably has a length that prevents the colonoscope 10 from detaching from the device 20 after the colonoscope is placed in the overtube. Illustratively, the strap 430 can be made from a ductile wire or Velcro. If the strap 430 is made from a ductile wire, the strap can be secured to anchors 431 and 432 located on the handle 21 and the colonoscope 10, respectively. Anchor 432 may be integral with colonoscope 10 or may include an adhesive suitable for application of colonoscope 10.

  While the above description emphasizes the use of the device 20 in the lower gastrointestinal tract, in particular, performing colonoscopy, the device of the present invention is also capable of being steered intraperitoneally in the upper gastrointestinal tract and laparoscopic procedures. It will be apparent to those skilled in the art that the endoscope or tool can be used as a variable stiffness trocar that can be advanced. The device 20 can also be reduced in size for use in urological endoscopy procedures. For example, a miniaturized overtube can be advanced through the patient's ureter to the kidney, along with a steerable kidney mirror, to access the organs below the kidney.

  While preferred exemplary embodiments of the present invention have been described above, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the invention. The appended claims are intended to cover all such changes and modifications as fall within the true spirit and scope of the invention.

FIG. 1 is a schematic diagram of the human colon, showing the usual difficulties encountered in advancing the colonoscope beyond the sigmoid colon. FIG. 2 is a side view of an exemplary apparatus of the present invention. 3A is a side cross-sectional exploded view of a first embodiment of the telescoping element of an overtube suitable for use in the apparatus of FIG. FIG. 3B is two side views of the telescoping element of FIG. 3A nested together. 4 is a side cross-sectional view of the distal region of the device of FIG. 2 constructed in accordance with the principles of the present invention. FIG. 5 is a side cross-sectional view of an exemplary arrangement of mechanisms suitable for use in the handle of the apparatus of FIG. FIG. 6 is a side cross-sectional view of details of a wire clamp system suitable for use in the handle of FIG. FIG. 7A is a schematic diagram of a method of using the apparatus of the present invention. FIG. 7B is a schematic diagram of a method of using the apparatus of the present invention. FIG. 7C is a schematic diagram of a method of using the apparatus of the present invention. FIG. 8 is a schematic diagram of an alternative process in a method of using the apparatus of the present invention. FIG. 9 is a side view of an alternative embodiment of the apparatus of the present invention. FIG. 10A is a schematic diagram of components of a tension mechanism suitable for stiffening the overtube of the present invention, where the components provide a fail-safe mode. FIG. 10B is a schematic illustration of components of a tension mechanism suitable for stiffening the overtube of the present invention, where the components provide a fail-safe mode. FIG. 10C is a schematic diagram of components of a tension mechanism suitable for stiffening the overtube of the present invention, where the components provide a failsafe mode. FIG. 11 is a cutaway side view of a tensioning mechanism incorporating the components of FIGS. 10A and 10B within the handle of the apparatus of FIG. FIG. 12A is a schematic perspective view of alternative components of a tensioning mechanism that each provide a failsafe mode. FIG. 12B is a schematic perspective view of alternative components of a tensioning mechanism that each provide a failsafe mode. FIG. 12C is a schematic perspective view of alternative components of a tensioning mechanism that each provide a failsafe mode. FIG. 12D is a schematic perspective view of alternative components of a tensioning mechanism that each provide a failsafe mode. 13A is a side cross-sectional view of a tensioning mechanism that incorporates the pulley manifold of FIG. 12B within the handle of the apparatus of FIG. FIG. 13B is an indicator that displays the state of the overtube. FIG. 14A is a cutaway side view of an alternative tension mechanism that transitions the overtube of the present invention between a flexible state and a rigid state in a continuous operation. FIG. 14B is a cutaway side view of an alternative tension mechanism that causes the overtube of the present invention to transition between a flexible state and a rigid state in a continuous operation. FIG. 14C is a cutaway side view of an alternative tension mechanism that transitions the overtube of the present invention between a flexible state and a rigid state in a continuous operation. FIG. 15 is a side cross-sectional view of yet another alternative tension mechanism using pneumatic actuation. FIG. 16 is a side cross-sectional view of a further alternative tensioning system that transitions the overtube of the present invention from a flexible state to a rigid state without substantial movement of the distal end of the overtube. 17A is a side cross-sectional view of an alternative element suitable for use in the overtube of FIG. FIG. 17B is a suitable roller element for use with the element of FIG. 17A. FIG. 18A illustrates the use of a lubricated rail in the overtube of the apparatus of FIG. 2 or FIG. 9 to facilitate the passage of a diagnostic or treatment device through the main lumen. FIG. 18B illustrates the use of a lubricated rail in the overtube of the apparatus of FIG. 2 or FIG. 9 to facilitate the passage of a diagnostic or treatment device through the main lumen. FIG. 19 is a side cross-sectional view of an alternative telescoping element having an integral lubrication lining. FIG. 20A is a side cross-sectional view of an alternative telescoping element that forms a smooth inner lumen when nested together. FIG. 20B is a side cross-sectional view of an alternative telescoping element that forms a smooth inner lumen when nested together. FIG. 21A is a still further alternative embodiment of the telescoping element of FIG. 3 where the telescoping element is macroscopically textured to enhance friction. FIG. 21B is a still further alternative embodiment of the telescoping element of FIG. 3 where the telescoping element is macroscopically textured to enhance friction. FIG. 21C is a still further alternative embodiment of the telescoping element of FIG. 3, where the telescoping element is macroscopically textured to enhance friction. FIG. 21D is a still further alternative embodiment of the telescoping element of FIG. 3 where the telescoping element is macroscopically textured to enhance friction. FIG. 22 is a schematic view of the lumen of the overtube of the present invention showing the use of multiple devices. FIG. 23 shows a side cross-sectional view of an alternative embodiment of an atraumatic tip constructed in accordance with the present invention. FIG. 24 shows a side cross-sectional view of an alternative embodiment of an atraumatic tip constructed in accordance with the present invention. FIG. 25 shows a side cross-sectional view of an alternative embodiment of an atraumatic tip constructed in accordance with the present invention. FIG. 26 shows a side cross-sectional view of an alternative embodiment of an atraumatic tip constructed in accordance with the present invention. FIG. 27 shows a side cross-sectional view of an alternative embodiment of an atraumatic tip constructed in accordance with the present invention. FIG. 28 shows a side cross-sectional view of an alternative embodiment of an atraumatic tip constructed in accordance with the present invention. FIG. 29 is an alternative embodiment of the overtube of the present invention having a tensioning system that uses a shape memory material. FIG. 30 is an alternative embodiment of the overtube of the present invention having a tension system that uses a shape memory material. FIG. 31A is a side cross-sectional view of an alternative embodiment of an overtube suitable for use in the present invention having a plurality of interconnected links surrounded by a clamp sleeve. FIG. 31B is a cross-sectional view of a portion of the sleeve. FIG. 31C is a cross-sectional view of a portion of the sleeve. FIG. 32 is a side cross-sectional view of a further alternative embodiment of an overtube constructed in accordance with the present invention having a helical bladder for actuating a clamp link. FIG. 33 is a side cross-sectional view of another alternative embodiment of the overtube of the present invention having a thermally actuatable band. FIG. 34A is a side cross-sectional view of a still further alternative embodiment of the overtube of the present invention comprising a series of helical links having different durometer areas. FIG. 34B is a side cross-sectional view of yet a further alternative embodiment of the overtube of the present invention comprising a series of helical links having different durometer areas. FIG. 35 is a side cross-sectional view of a still further alternative embodiment of an overtube suitable for use with the present invention comprising a series of links having interlocking proximal and distal rims. FIG. 36 is a side cross-sectional view of another alternative embodiment of the present invention comprising a series of links forming a cooperating joint. FIG. 37 is a side cross-sectional view of yet another alternative embodiment of an overtube having a thermally regulated stiffness. FIG. 38A is a schematic diagram of yet another alternative embodiment of an overtube suitable for use with the present invention, wherein the diameter of the tension wire lumen extending through the overtube changes in response to electrical energy application. It is. FIG. 38B is a schematic diagram of yet another alternative embodiment of an overtube suitable for use with the present invention, wherein the diameter of the tension wire lumen extending through the overtube changes in response to electrical energy application. It is. FIG. 38C is a schematic diagram of yet another alternative embodiment of an overtube suitable for use with the present invention, wherein the diameter of the tension wire lumen extending through the overtube changes in response to electrical energy application. It is. FIG. 39 is a side cross-sectional view of yet another alternative embodiment of an overtube having a series of electrically actuated links arranged in an overlapping manner around a series of rigid links. FIG. 40A is a side cross-sectional view of an electrically operated telescoping link. FIG. 40B is a side cross-sectional view of the plurality of electrically actuated telescopic links of FIG. 40A nested together to form a suitable overtube for use with the device of the present invention. FIG. 41 is a side cross-sectional view of a disposable sheath for use with the overtube of the present invention. FIG. 42 is a schematic side view of a strap coupling the device of the present invention to a colonoscope.

Claims (7)

An apparatus for advancing a first diagnostic or therapeutic device to an unsupported anatomical hollow body organ comprising:
A handle; and an overtube attached to the handle comprising:
Proximal and distal ends,
External surface,
An overtube having an inner surface extending between the proximal end and the distal end and defining a lumen that allows passage of the first diagnostic or therapeutic device, wherein the overtube A flexible state that facilitates insertion of the overtube into a hollow body organ and the internal surface during insertion or withdrawal of the first diagnostic or therapeutic device through the lumen An overtube having a rigid state that resists bending forces applied to the first body; and a first portion extending through the entire length of the lumen to provide a barrier between the inner surface and the first diagnostic or treatment device And a disposable sheath having a second portion extending the entire length of the outer surface. The device of claim 1, wherein the disposable sheath comprises a hydrophobic material. The apparatus of claim 1, wherein the disposable sheath comprises a non-twisted coil. The apparatus of claim 1, wherein the first portion comprises a thin flexible material. The apparatus according to claim 1, wherein the overtube comprises a plurality of telescoping links, each having a side wall. The apparatus of claim 5, further comprising:
An apparatus comprising: a plurality of tension wire holes extending through a sidewall of each of the plurality of telescoping links; and at least one tension wire movably disposed through one or more of the plurality of tension wire holes. The apparatus of claim 6, further comprising a tension mechanism selectively operable to transition an overtube between the flexible state and the rigid state.

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