Endoscope with guiding apparatus Number:6,800,056 from the United States Patent and Trademark Office (PTO) owispatent An endoscope with guiding apparatus is described herein. A steerable endoscope is described having an elongate body with a manually or selectively steerable distal portion, an automatically controlled portion, a flexible and passively manipulated proximal portion, and an externally controlled and manipulatable tracking rod or guide. The tracking rod or guide is positioned within a guide channel within the endoscope and slides relative to the endoscope. When the guide is in a flexible state, it can conform to a curve or path defined by the steerable distal portion and the automatically controlled portion. The guide can then be selectively rigidized to assume that curve or path. Once set, the endoscope can be advanced over the rigidized guide in a monorail or "piggy-back" fashion so that the flexible proximal portion follows the curve held by the guide until the endoscope reaches a next point of curvature within a body lumen.<H apparatus, Endoscope, Endoscope, with, , 6800056.html, Patent, pto, 6800056

Title: Endoscope with guiding apparatus

Abstract: An endoscope with guiding apparatus is described herein. A steerable endoscope is described having an elongate body with a manually or selectively steerable distal portion, an automatically controlled portion, a flexible and passively manipulated proximal portion, and an externally controlled and manipulatable tracking rod or guide. The tracking rod or guide is positioned within a guide channel within the endoscope and slides relative to the endoscope. When the guide is in a flexible state, it can conform to a curve or path defined by the steerable distal portion and the automatically controlled portion. The guide can then be selectively rigidized to assume that curve or path. Once set, the endoscope can be advanced over the rigidized guide in a monorail or "piggy-back" fashion so that the flexible proximal portion follows the curve held by the guide until the endoscope reaches a next point of curvature within a body lumen.

Patent Number: 6,800,056 Issued on 10/05/2004 to Tartaglia, et al.

Inventors: Tartaglia; Joseph M. (Morgan Hill, CA), Belson; Amir (Cupertino, CA), Ohline; Robert Matthew (Redwood City, CA)
Assignee: NeoGuide Systems, Inc. (Los Gatos, CA)

Appl. No.: 10/087,100

Filed: March 1, 2002

Current U.S. Class: 600/114

Field of Search: 600/114,144,145,146,115,139

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Primary Examiner: Flanagan; Beverly M.
Attorney, Agent or Firm: Wilson, Sonsini, Goodrich & Rosati

Parent Case Text

This application is a continuation-in-part of U.S. patent application Ser. No. 09/969,927 entitled "Steerable Segmented Endoscope and Method of Insertion" filed Oct. 2, 2001, which is a continuation-in-part of U.S. patent application Ser. No. 09/790,204 entitled "Steerable Endoscope and Improved Method of Insertion" filed Feb. 20, 2001, which claims the benefit of priority to U.S. Provisional Patent Application Serial No. 60/194,140 entitled the same and filed Apr. 3, 2000, all of which are incorporated herein by reference in their entirety.

Claims

We claim:

1. A method of advancing an instrument along an arbitrary path, comprising: selectively steering a distal portion of the instrument to assume a selected shape along an arbitrary path; advancing an elongate guide along the instrument such that a portion of the guide conforms to and assumes the selected shape; and maintaining a position of the guide while advancing the instrument along the guide such that a proximal portion of the instrument assumes the selected shape defined by the guide, wherein the elongate guide is freely slidable along the length of the instrument such that advancing of the instrument along the guide is unconstrained.

2. The method of claim 1 wherein prior to advancing the elongate guide along the instrument, further comprising advancing the instrument distally while configuring a controllable portion of the instrument to assume the selected shape of the distal portion, wherein the controllable portion is proximal of the distal portion.

3. The method of claim 1 further comprising measuring a depth change of the instrument while advancing the instrument distally.

4. The method of claim 3 further comprising incrementing a current depth by the depth change.

5. The method of claim 1 further comprising releasing the position of the guide and further advancing the guide along the instrument.

6. The method of claim 1 further comprising withdrawing the guide from the instrument.

7. The method of claim 1 wherein the elongate guide is advanced along the instrument through a lumen defined within the instrument.

8. The method of claim 1 wherein the distal portion of the instrument selectively assumes a second shape when the instrument is advanced along the guide.

9. The method of claim 8 further comprising advancing at least one additional elongate guide along the instrument such that the additional elongate guide conforms to and assumes the second shape.

10. The method of claim 9 further comprising rigidizing the additional elongate guide such that the second shape is maintained by the additional guide.

11. The method of claim 1 wherein maintaining the position of the guide comprises rigidizing the guide such that the guide rigidly assumes a position of the selected shape.

12. The method of claim 11 wherein rigidizing the guide comprises applying tension to a tensioning member disposed within the guide such that a plurality of adjacent segments comprising the guide are compressed.

13. The method of claim 11 wherein rigidizing the guide comprises applying a vacuum force within a lumen defined within the guide such that a plurality of adjacent segments comprising the guide are compressed.

14. An apparatus for insertion into a body cavity, comprising: an elongate body having a proximal portion and a selectively steerable distal portion and defining a lumen therebetween, the steerable distal portion being configurable to assume a selected shape along an arbitrary path; an elongate guide having a proximal section, a distal section, and a length therebetween, the guide being slidably disposed without constraint within the lumen along the length for selectively supporting the body, wherein the guide is configured to conform to and selectively maintain the selected shape assumed by the steerable distal portion, and wherein the proximal portion of the elongate body when advanced distally is configured to conform to the selected curve maintained by the guide.

15. The apparatus of claim 14 further comprising a controllable portion located proximally of the distal portion, wherein the controllable portion is configured to propagate the selected shape along the controllable portion.

16. The apparatus of claim 14 wherein the selectively steerable distal portion is configurable via a control located externally of the body cavity.

17. The apparatus of claim 14 wherein the proximal portion comprises a flexible tubular member.

18. The apparatus of claim 15 wherein the controllable portion comprises a plurality of pivotally connected segments.

19. The apparatus of claim 18 wherein each of the segments comprises an actuator for propagating the selected shape along the controllable portion.

20. The apparatus of claim 19 wherein the actuator comprises a type of motor selected from the group consisting of pneumatic, hydraulic, electromechanical motors, and drive shafts.

21. The apparatus of claim 18 wherein the controllable portion comprises at least two pivotally connected segments.

22. The apparatus of claim 14 wherein the elongate guide is configured to assume the selected shape when the guide is in a flexible state and wherein the guide is further configured to maintain the selected shape when the guide is in a rigidized state.

23. The apparatus of claim 22 wherein the elongate guide is configured to selectively rigidize along the length of the guide to maintain the selected shape in the rigidized state.

24. The apparatus of claim 22 wherein the proximal section of the elongate guide is in communication with a guide controller for selectively rigidizing the guide along its length.

25. The apparatus of claim 22 wherein the elongate guide comprises a plurality of adjacent segments each defining a channel therethrough such that a common channel is defined through the length of the guide.

26. The apparatus of claim 25 further comprising a tensioning member disposed within the common channel such that applying a force to the tensioning member compresses the adjacent segments together.

27. The apparatus of claim 25 wherein the elongate guide is configured to maintain a position of adjacent segments relative to each other upon applying a vacuum force within the common channel.

28. The apparatus of claim 14 further comprising an obstruction located within the lumen distally of the guide for preventing contamination of the guide.

29. The apparatus of claim 28 wherein the obstruction is selectively removable from a passageway of the lumen.

30. The apparatus of claim 29 wherein the obstruction comprises a trap or an expandable balloon.

31. The apparatus of claim 14 further comprising at least one additional elongate guide having a proximal section, a distal section, and a length therebetween, the additional guide also being slidably disposed within the elongate body and being configured to conform to and selectively maintain an additional selected curve assumed by the steerable distal portion.

32. The apparatus of claim 14 further comprising a tubular covering disposed over at least a majority of the length of the elongate guide.

Description

TECHNICAL FIELD OF THE INVENTION

The present invention relates generally to endoscopes and endoscopic procedures. More particularly, it relates to a method and apparatus to facilitate insertion of a flexible endoscope along a tortuous path, such as for colonoscopic examination and treatment.

BACKGROUND OF THE INVENTION

An endoscope is a medical instrument for visualizing the interior of a patient's body. Endoscopes can be used for a variety of different diagnostic and interventional procedures, including colonoscopy, bronchoscopy, thoracoscopy, laparoscopy and video endoscopy.

Colonoscopy is a medical procedure in which a flexible endoscope, or colonoscope, is inserted into a patient's colon for diagnostic examination and/or surgical treatment of the colon. A standard colonoscope is typically 135-185 cm in length and 12-19 mm in diameter, and includes a fiberoptic imaging bundle or a miniature camera located at the instrument's tip, illumination fibers, one or two instrument channels that may also be used for insufflation or irrigation, air and water channels, and vacuum channels. The colonoscope is inserted via the patient's anus and is advanced through the colon, allowing direct visual examination of the colon, the ileocecal valve and portions of the terminal ileum.

Insertion of the colonoscope is complicated by the fact that the colon represents a tortuous and convoluted path. Considerable manipulation of the colonoscope is often necessary to advance the colonoscope through the colon, making the procedure more difficult and time consuming and adding to the potential for complications, such as intestinal perforation. Steerable colonoscopes have been devised to facilitate selection of the correct path though the curves of the colon. However, as the colonoscope is inserted farther and farther into the colon, it becomes more difficult to advance the colonoscope along the selected path. At each turn, the wall of the colon must maintain the curve in the colonoscope. The colonoscope rubs against the mucosal surface of the colon along the outside of each turn. Friction and slack in the colonoscope build up at each turn, making it more and more difficult to advance, withdraw, and loop the colonoscope. In addition, the force against the wall of the colon increases with the buildup of friction. In cases of extreme tortuosity, it may become impossible to advance the colonoscope all of the way through the colon.

Steerable endoscopes, catheters and insertion devices for medical examination or treatment of internal body structures are described in the following U.S. patents, the disclosures of which are hereby incorporated by reference in their entirety: U.S. Pat. Nos. 4,543,090; 4,753,223; 5,337,732; 5,337,733; 5,383,852; 5,487,757; 5,624,381; 5,662,587; and 5,759,151.

SUMMARY OF THE INVENTION

Accordingly, an improved endoscopic apparatus is disclosed herein for the examination of a patient's colon or other internal bodily cavities with minimal impingement upon bodily cavities or upon the walls of the organs. A steerable endoscope having an elongate body with a manually or selectively steerable distal portion, an automatically controlled portion, which may be optionally omitted from the device, a flexible and passively manipulated proximal portion, and an externally controlled and manipulatable tracking rod or guide is described below. The tracking rod or guide may be slidably positioned within a guide channel or lumen within the endoscope or it may be externally positionable such that the guide and the endoscope may slide relative to one another along a rail or channel located along an external surface of the endoscope.

In operation, the steerable distal portion of the endoscope may be first advanced into a patient's rectum via the anus. The endoscope may be simply advanced, either manually or automatically by a motor, until the first curvature is reached. At this point, the steerable distal portion may be actively controlled by the physician or surgeon to attain an optimal curvature or shape for advancement of the endoscope. The optimal curvature or shape is considered to be the path which presents the least amount of contact or interference from the walls of the colon. In one variation, once the desired curvature has been determined, the endoscope may be advanced further into the colon such that the automatically controlled segments of controllable portion follow the distal portion while transmitting the optimal curvature or shape proximally down the remaining segments of the controllable portion. The operation of the controllable segments will be described in further detail below.

Alternatively, once the steerable distal portion has been steered or positioned for advancement, the guide may be advanced distally in its flexible state along or within the endoscope until it reaches a distal position, i.e., preferably some point distal of the flexible proximal portion. Regardless whether the optional controllable portion is omitted or not from the device, the guide may be advanced near or to the end of the distal portion. Once the guide has been advanced, it may directly attain and conform to the curvature or shape defined by the steerable distal portion.

Preferably, the guide is advanced to the distal end of steerable distal portion or, if the controllable portion is included in the device, the guide may be advanced to the distal end of the controllable portion, or to some point between the two portions. The guide may be advanced to any distal position as long as a portion of the guide attains and conforms to the optimal curvature or shape. Prior to advancing the endoscope over the guide, the guide may be left in its flexible state or it may be optionally rigidized, as discussed further below. If left in its flexible state, the guide may possibly provide desirable column strength to the endoscope as it is advanced through the colon over the guide. It is preferable, however, that the guide is rigidized once it has attained and conformed to the curvature. This allows the flexible proximal portion, i.e., the passive portion, to remain flexible and lightweight in structure. As the position of the guide is preferably rigidized and maintained, the endoscope may then be advanced over the guide in a monorail or "piggy-back" fashion so that the flexible proximal portion follows the curve held by the guide until the endoscope reaches the next point of curvature.

This process of alternately advancing the guide and the endoscope may be repeated to advance the entire endoscope through the colon while the guide may be alternatively rigidized and relaxed while being advanced distally. While the endoscope is advanced through the colon, the physician or surgeon may stop the advancement to examine various areas along the colon wall using, e.g., an imaging bundle located at the distal end of the endoscope. During such examinations, the guide may be temporarily withdrawn from the endoscope to allow for the insertion of other tools through the guide channel if there is no separate channel defined within the endoscope for the guide. The guide may also be withdrawn through the instrument to any location within the body of the endoscope. In other words, the guide may be withdrawn partially or removed entirely from the endoscope at any time, if desired, because there are no constraints which may limit the travel of the guide through the body of the endoscope. After a procedure has been completed on the colon wall, the tool may be withdrawn from the guide channel and the guide may be reintroduced into the endoscope so that the endoscope may optionally be advanced once again into the colon.

A further variation on advancing the endoscope may use multiple guides which are alternately rigidized while being advanced distally along a path. Although multiple guides may be used, two guides are preferably utilized. As the endoscopic device approaches a curvature, a first guide may be advanced in a relaxed and flexible state towards the steerable distal end of the device. While being advanced, the first guide preferably conforms to the shape defined by the distal end and the first guide may be subsequently rigidized to maintain this shape. The device may then be advanced further distally along the pathway while riding over the rigidized first guide.

After the device has been advanced to its new position, a second guide may also be advanced distally in its relaxed state through the device up to the distal end while the first guide is maintained in its rigidized state. The second guide may then conform to the new shape defined by the distal end of the device and become rigidized to maintain this new shape. At this point, the first guide is also preferably maintained in its rigid state until the distal end of the device has been advanced further distally. The first guide may then be relaxed and advanced while the rigidity of the second guide provides the strength for advancing the guide. This procedure may be repeated as necessary for negotiating the pathway.

To withdraw the endoscope from within the colon, the procedure above may be reversed such that the withdrawal minimally contacts the walls of the colon. Alternatively, the guide may simply be removed from the endoscope while leaving the endoscope within the colon. Alternatively, the guide may be left inside the endoscope in the relaxed mode. The endoscope may then be simply withdrawn by pulling the proximal portion to remove the device. This method may rub or contact the endoscope upon the walls of the colon, but any impingement would be minimal.

The selectively steerable distal portion can be selectively steered or bent up to a full 180.degree. bend in any direction. A fiberoptic imaging bundle and one or more illumination fibers may extend through the body from the proximal portion to the distal portion. The illumination fibers are preferably in communication with a light source, i.e., conventional light sources, which may be positioned at some external location, or other sources such as LEDs. Alternatively, the endoscope may be configured as a video endoscope with a miniaturized video camera, such as a CCD camera, positioned at the distal portion of the endoscope body. The video camera may be used in combination with the illumination fibers. Optionally, the body of the endoscope may also include one or two access lumens that may optionally be used for insufflation or irrigation, air and water channels, and vacuum channels, etc. Generally, the body of the endoscope is highly flexible so that it is able to bend around small diameter curves without buckling or kinking while maintaining the various channels intact. The endoscope can be made in a variety of other sizes and configurations for other medical and industrial applications.

The optional controllable portion is composed of at least one segment and preferably several segments which may be controllable via a computer and/or controller located at a distance from the endoscope. Each of the segments preferably have an actuator mechanically connecting adjacent segments to allow for the controlled motion of the segments in space. The actuators driving the segments may include a variety of different types of mechanisms, e.g., pneumatic, vacuum, hydraulic, electromechanical motors, drive shafts, etc. If a mechanism such as a flexible drive shaft were utilized, the power for actuating the segments would preferably be developed by a generator located at a distance from the segments, i.e., outside of a patient during use, and in electrical and mechanical communication with the drive shaft. A proximal portion comprises the rest of the endoscope and preferably a majority of the overall length of the device. The proximal portion is preferably a flexible tubing member which may conform to an infinite variety of shapes. It may also be covered by a polymeric covering optionally extendable over the controllable portion and the steerable distal portion as well to provide a smooth transition between the controllable segments and the flexible tubing of the proximal portion. The controllable portion may be optionally omitted from the endoscope. A more detailed description on the construction and operation of the segments may be found in U.S. patent application Ser. No. 09/969,927 entitled "Steerable Segmented Endoscope and Method of Insertion" filed Oct. 2, 2001, which has been incorporated by reference in its entirety.

A proximal handle may be attached to the proximal end of the proximal portion and may include imaging devices connected to the fiberoptic imaging bundle for direct viewing and/or for connection to a video camera or a recording device. The handle may be connected to other devices, e.g., illumination sources and one or several luer lock fittings for connection to various instrument channels. The handle may also be connected to a steering control mechanism for controlling the steerable distal portion. The handle may optionally have the steering control mechanism integrated directly into the handle, e.g., in the form of a joystick, conventional disk controller using dials or wheels, etc. An axial motion transducer may also be provided for measuring the axial motion, i.e., the depth change, of the endoscope body as it is advanced and withdrawn. The axial motion transducer can be made in many possible configurations. As the body of the endoscope slides through the transducer, it may produce a signal indicative of the axial position of the endoscope body with respect to the fixed point of reference. The transducer may use various methods for measuring the axial position of the endoscope body.

The guide is generally used to impart a desired curvature initially defined by the steerable portion and/or by the optional controllable portion to the passive proximal portion when the endoscope is advanced. If advanced into the steerable portion, the guide is preferably advanced to or near the distal tip of the portion. It is also used to impart some column strength to the proximal portion in order to maintain its shape and to prevent any buckling when axially loaded. Preferably, the guide is slidably disposed within the length of the endoscope body and may freely slide entirely through the passive proximal portion, through the controllable portion, and the steerable distal portion. The extent to which the guide may traverse through the endoscope body may be varied and adjusted according to the application, as described above. Furthermore, the proximal end of the guide may be routed through a separate channel to a guide controller which may be used to control the advancement and/or withdrawal of the guide and which may also be used to selectively control the rigidity of the guide as controlled by the physician.

The structure of the guide may be varied according to the desired application. The following descriptions of the guide are presented as possible variations and are not intended to be limiting in their structure. For instance, the guide may be comprised of two coaxially positioned tubes separated by a gap. Once the guide has been placed and has assumed the desirable shape or curve, a vacuum force may be applied to draw out the air within the gap, thereby radially deforming one or both tubes such that they come into contact with one another and lock their relative positions.

Another variation on the guide is one which is rigidizable by a tensioning member. Such a guide may be comprised of a series of individual segments which are rotatably interlocked with one another in series. Each segment may further define a common channel through which a tensioning member may be positioned while being held between a proximal and a distal segment. During use, the tensioning member may be slackened or loosened enough such that the guide becomes flexible enough to assume a shape or curve defined by the endoscope. When the guide is desirably situated and has assumed a desired shape, the tensioning member may then be tensioned, thereby drawing each segment tightly against one another to hold the desired shape.

Another variation may use a guide which is comprised of interlocking ball-and-socket type joints which are gasketed at their interfaces. Such a design may utilize a vacuum pump to selectively tighten and relax the individual segments against one another. Other variations may include alternating cupped segments and ball segments, a series of collinear sleeve-hemisphere segments, as well as other designs which may interfit with one another in series. Such a guide may be tightened and relaxed either by tensioning members or vacuum forces.

A further variation on the guide is a coaxially aligned stiffening member. This assembly may include a first subassembly comprising a number of collinearly nested segments which may be held by a tensioning member passing through each segment. The first subassembly may be rigidized from a flexible or flaccid state by pulling on this tensioning member. A second subassembly may comprise a number of annular segments also collinearly held relative to one another with one or more tensioning members passing through each annular segment. The second subassembly preferably defines a central area in which the first nested subassembly may be situated coaxially within the second subassembly. The first subassembly is preferably slidably disposed relative to the second subassembly thereby allowing each subassembly to be alternately advanced in a flexible state and alternately rigidized to allow the other subassembly to be advanced. This design presents a small cross-section relative to the endoscope or device through which it may be advanced.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a representation of a conventional endoscope in use.

FIG. 2 shows a variation of an endoscopic device of the present invention.

FIG. 3A shows a side view of an endoscopic device variation with the outer layers removed to reveal a guiding apparatus disposed within.

FIGS. 3B and 3C show cross-sectional views of various examples for obstructing the guide lumen of the endoscope.

FIGS. 4A to 4C show cross-sectional views of various examples of guiding apparatus which may be used to guide an endoscope.

FIGS. 5A and 5B show the cross-sectioned end and side views, respectively, of a guiding apparatus with a vacuum-actuated rigidizing variation.

FIGS. 6A and 6B show the cross-sectioned end and side views, respectively, of a guiding apparatus with a tensioning or pre-tensioned element for rigidizing the guide.

FIGS. 7A and 7B show the cross-sectioned end and side views, respectively, of a guiding apparatus with a segmented vacuum-actuated rigidizing variation.

FIGS. 8A and 8B show the cross-sectioned end and side views, respectively, of a guiding apparatus with interconnecting jointed segments for rigidizing the guide.

FIGS. 9A to 9C show end, side, and cross-sectioned views, respectively, of another variation on the guiding apparatus.

FIG. 10 shows the cross-sectioned side view of another variation on the guiding apparatus having alternating bead and sleeve segments.

FIG. 11A shows a side view of a nested guiding apparatus which is part of a coaxial stiffening assembly.

FIG. 11B shows a side view of an annular guiding apparatus which is also part of the coaxial stiffening assembly.

FIG. 11C shows the combination of the guides from FIGS. 11A and 11B.

FIGS. 12A to 12H illustrate a representative example of advancing an endoscope through a patient's colon using a guiding apparatus to assist in advancing the endoscope.

FIGS. 13A and 13B show a variation on the withdrawal of the endoscope with or without the guiding apparatus for the selective treatment of sites along the patient's colon.

FIGS. 14A to 14C illustrate a representative example of advancing an endoscope through a tortuous path using the coaxial guiding apparatus shown in FIGS. 11A to 11C.

FIGS. 15A to 15E illustrate another variation of advancing an endoscope through a tortuous path using multiple guiding apparatuses.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 shows a prior art colonoscope 10 being employed for a colonoscopic examination of a patient's colon C. The colonoscope 10 has a proximal handle 16 and an elongate body 12 with a steerable distal portion 14. The body 12 of the colonoscope 10 has been lubricated and inserted into the colon C via the patient's anus A. Utilizing the steerable distal portion 14 for guidance, the body 12 of the colonoscope 10 has been maneuvered through several turns in the patient's colon C to the ascending colon G. Typically, this involves a considerable amount of manipulation by pushing, pulling and rotating the colonoscope 10 from the proximal end to advance it through the turns of the colon C. After the steerable distal portion 14 has passed, the wall of the colon C maintains the curve in the flexible body 12 of the colonoscope 10 as it is advanced. Friction develops along the body 12 of the colonoscope 10 as it is inserted, particularly at each turn in the colon C. Because of the friction, when the user attempts to advance the colonoscope 10, the body 12' tends to move outward at each curve, pushing against the wall of the colon C, which exacerbates the problem by increasing the friction and making it more difficult to advance the colonoscope 10. On the other hand, when the colonoscope 10 is withdrawn, the body 12" tends to move inward at each curve taking up the slack that developed when the colonoscope 10 was advanced. When the patient's colon C is extremely tortuous, the distal end of the body 12 becomes unresponsive to the user's manipulations, and eventually it may become impossible to advance the colonoscope 10 any farther. In addition to the difficulty that it presents to the user, tortuosity of the patient's colon also increases the risk of complications, such as intestinal perforation.

FIG. 2 shows a variation of the steerable endoscope 20 of the present invention. The endoscope 20 has an elongate body 21 with a manually or selectively steerable distal portion 24, an automatically controlled portion 28, which may be optionally omitted from the device, a flexible and passively manipulated proximal portion 22, and