Method and apparatus for advancing an instrument along an arbitrary path using an introducer sheath

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.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application is a continuation-in-part of U.S. patent application Ser. No. 10 / 087,100 entitled “Endoscope with Guiding Apparatus” filed Mar. 1, 2002, which 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 Ser. No. 60 / 194,140 entitled the same and filed Apr. 3, 2000, all of which are incorporated herein by reference in their entirety.FIELD OF THE INVENTION [0002] 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...

AI Technical Summary

Benefits of technology

[0009] In one variation, the guide is shorter than the full length of the endoscope, e.g., approximately the length of the controllable portion, and this shortened guide can be preloaded through the proximal end of the endoscope or through the handle of the endoscope. Once the guide is inserted, it may be advanced distally through the endoscope to the distal tip of the endoscope. As the user advances the endoscope distally, the automatically controlled segments of the proximal controllable portion propagate the selected curves down the endoscope, and the guide, in its flexible state, passively conforms to the shape of the desired pathway. Once the endoscope has advanced to a desired position, e.g. to a depth less than the length of the controllable portion of the endoscope, the user can rigidize the guide and maintain it at that depth (or axial position). The endoscope can then be further advanced relative to the rigidized guide, sliding over the rigid guide and along the selected pathway. Thus, the surgeon or physician only needs to lock the guide in position once. If the controllable region of the endoscope and the guide are each at least half of the length of the endoscope, the entire endoscope can conform to a selected pathway in this manner. It is also possible to reposition the guide easily by relaxing and / or unlocking it from its rigidized axial position and then moving the guide into its new position.

[0011] 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 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.

[0022] 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 held or 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.

Problems solved by technology

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.

However, as the colonoscope is inserted farther and farther into the colon, it becomes more difficult to advance the colonoscope along the selected path.

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.

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