Expandable transluminal sheath

Abstract

Disclosed is an expandable transluminal sheath, for introduction into the body while in a first, low cross-sectional area configuration, and subsequent expansion of at least a part of the distal end of the sheath to a second, enlarged cross-sectional configuration. The distal end of the sheath is maintained in the first, low cross-sectional configuration and expanded using a radial dilatation device. In an exemplary application, the sheath is utilized to provide access for diagnostic or therapeutic procedures such as ureteroscopy, cardiac electrophysiology, gastroenterology, and spinal access.

Description

PRIORITY CLAIM [0001] This application claims priority to U.S. application Ser. No. 60 / 608,355, filed on Sep. 9, 2004, titled Expandable Transluminal Sheath, the entirety of which is hereby incorporated herein by reference.BACKGROUND OF THE INVENTION [0002] 1. Field of the Invention [0003] The present invention relates to medical devices and, more particularly, to methods and devices for accessing the mammalian urinary tract. In one application, the present invention relates to methods and devices for providing access to the ureter and kidney. [0004] 2. Description of the Related Art [0005] A wide variety of diagnostic or therapeutic procedures involves the introduction of a device through a natural access pathway. A general objective of access systems, which have been developed for this purpose, is to minimize the cross-sectional area of the access lumen, while maximizing the available space for the diagnostic or therapeutic instrument. These procedures are especially suited for th...

AI Technical Summary

Benefits of technology

[0015] Another embodiment of the present invention comprises an expandable medical access sheath for providing minimally invasive access to body lumens or cavities, length of proximal sheath tubing, said proximal sheath tubing being non-expandable. The sheath includes a length of distal sheath tubing. The distal sheath tubing is collapsed to a diameter smaller than that of the proximal sheath tubing. A transition zone exists between the distal sheath tubing and the proximal sheath tubing. The transition zone tapers between the larger diameter proximal sheath tubing and the smaller diameter distal sheath tubing. A dilator is disposed within both the proximal sheath tubing and the distal sheath tubing. Radial expansion of the dilator causes the distal sheath tubing to expand diametrically to substantially the same inner diameter as that of the proximal sheath tubing.

[0029] Another embodiment of the invention comprises an axially elongate sheath with a proximal end, a distal end, and a defined internal lumen. At least a portion of the distal end of the sheath is expandable from a first radially collapsed configuration to a second, radially expanded configuration. The expandable portion of the sheath is comprised of a braid, a plurality of longitudinal runners, a tube with staggered “brickwork” slits running longitudinally, or other radially expandable pattern. The sheath may further comprise an elastomeric outer sleeve about its expandable region fabricated from materials such as, but not limited to, polyurethane, silicone elastomer, C-Flex, latex rubber, or the like. An internal translation dilator is operated from the proximal end of the sheath and is advanced proximally to expand the distal end of the sheath. The outer diameter of the translation dilator is slightly smaller than the inside diameter of the proximal end of the sheath. The translation dilator is slightly rounded or tapered or slit to minimize strain and catching on the interior surfaces of the sheath. Once the translation dilator is advanced into the expandable portion of the sheath, the expandable portion of the sheath expands. The inner lumen of the translation dilator becomes the inner lumen of the sheath along its entire length. If a braided material is used to create the expandable portion of the sheath, it may be beneficial to affix stabilization wires between the distal end of the braid and some portion of the non-expandable portion of the sheath. These stabilization wires may prevent constriction of the braid when the translation dilator is being advanced therethrough.

Problems solved by technology

One of the issues that arise during ureteroscopy is the presence of an obstruction or stenosis in the ureter, which is sometimes called a stricture, that prohibits a catheter with a large enough working channel from being able to be advanced into the ureter.

Such conditions may preclude the minimally invasive approach and require more invasive surgical procedures in order to complete the task.

Alternatively, urologists may start with a larger catheter and then need to downsize to a smaller catheter, a technique that results in a waste of time and expenditure.

Finally, a urologist may need to dilate the ureter with a dilation system before placing the current devices, again a waste of time and a need for multiple devices to perform the procedure.

Images