Flexible urinary catheter
The urinary catheter tube with inner surface grooves addresses the challenge of navigating urethral strictures and bends by balancing rigidity and flexibility, enhancing user comfort and ease of insertion.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- HOLLISTER INCORPORAED
- Filing Date
- 2025-11-03
- Publication Date
- 2026-05-15
AI Technical Summary
Existing urinary catheters face challenges in being sufficiently rigid for advancement through the urethra while also being flexible enough to navigate strictures and bends, often causing user discomfort and requiring tedious orientation adjustments.
A urinary catheter tube with grooves on the inner surface providing varying flexibility through controlled dimensions, shapes, and spacing, combined with a smooth outer surface for ease of insertion and user comfort.
The catheter tube achieves ease of insertion and comfort by maintaining rigidity for advancement while flexibility for navigating urethral obstacles, reducing friction and discomfort.
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Figure US2025053757_15052026_PF_FP_ABST
Abstract
Description
Attorney Docket: 3400-0349.01 (821 PCT)FLEXIBLE URINARY CATHETERRelated ApplicationThe present application claims the benefit of and priority to U.S. Provisional Application No. 63 / 716,863, filed November 6, 2024, the disclosure of which is hereby incorporated herein by reference in its entirety.DESCRIPTIONTECHNICAL FIELD
[0001] The present disclosure generally relates to a urinary catheter assembly, and more particularly, to a flexible urinary catheter tube having lumen surface grooves for use in a urinary catheter assembly.BACKGROUND
[0002] Intermittent catheterization is a suitable intervention for some users experiencing incomplete bladder emptying. A urinary catheter used for intermittent catheterization is typically provided as a single use, individually packaged item and may include a gel lubricant or hydrophilic coating to reduce friction during insertion into the urethra. With the advent of intermittent urinary catheters, users experiencing urinary system disfunction can conveniently self- catheterize to drain the bladder. Users experiencing urinary incontinence may self-catheterize several times per day.
[0003] Self-catheterization involves removing the catheter assembly from its package and inserting and advancing the catheter tube through the urethra.Some catheter assemblies include an introducer tip in which a leading (insertion) end of the catheter tube is initially housed to aid insertion of the catheter tube into the urethra. The leading end of the catheter tube is fed through the introducer tip and advanced through the urethra until insertion into the bladder.
[0004] A conventional catheter tube should be rigid enough to advance through the urethra to the bladder as the user inserts the catheter tube. However, a catheter that is too rigid may cause discomfort to the user, for example, when advancing through a stricture or bend in the urethra. To avoid such discomfort, flexible catheter tubes have been developed. However, a catheter tube that is tooAttorney Docket: 3400-0349 (821 P) flexible may not be able to pass through a stricture or a bend in the urethra, and in turn, may not be advanced to bladder.
[0005] Another catheter tube has been formed having a flexible side and a rigid side laterally opposite to the flexible side. Such a catheter tube may flex in one direction to navigate strictures or bends while being advanced in the urethra. However, such a catheter tube must be properly oriented to flex in the direction needed to navigate through the stricture or bend. Thus, a user may need to rotate the catheter tube during insertion to find an orientation in which the tube may be comfortably advanced. A trial and error process may be needed to orient the catheter tube in such a way, which may be tedious and cause further discomfort to the user while finding a suitable orientation.
[0006] Thus, it would be desirable to provide a urinary catheter assembly for intermittent catheterization having a flexible catheter tube that is sufficiently rigid for advancing through the urethra and sufficiently flexible for navigating strictures, bend, and / or other obstacles in the urethra, while providing suitable comfort and ease of use to the user.SUMMARY
[0007] There are several aspects of the present subject matter. In one aspect, a urinary catheter tube includes a tubular wall having a hollow interior, a smooth outer surface and inner surface surrounding the hollow interior. A thickness of the tubular wall extends from the smooth outer surface to the inner surface. One or more grooves are formed in the inner surface, the one or more grooves having a shape and a depth extending into the thickness of the tubular wall, the one or more grooves configured to provide a selected flexibility. One or more drainage openings extend through the tubular wall.Brief Description of Drawings
[0008] FIG. 1 is a diagram schematically representing a cross-sectional view of a flexible urinary catheter tube according to an example of the present disclosure;
[0009] FIG 2. is a diagram schematically representing a cross-sectionalAttorney Docket: 3400-0349 (821 P) view of the flexible urinary catheter tube of FIG. 1 in a flexed condition;
[0010] FIG. 3 is an enlarged view showing a portion of the flexible urinary catheter tube of FIGS. 1 and 2;
[0011] FIG. 4 is a diagram schematically representing a cross-sectional view of a flexible urinary catheter tube according to another example of the present disclosure; and
[0012] FIGS. 5a-5a are diagrams schematically representing cross- sectional end views of example variations of the flexible urinary catheter tubes of FIGS. 1-4.DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS
[0013] The embodiments disclosed herein are for the purpose of providing a description of the present subject matter, and it is understood that the subject matter may be embodied in various other forms and combinations not shown in detail. Therefore, specific embodiments and features disclosed herein are not to be interpreted as limiting the subject matter as defined in the accompanying claims.
[0014] With reference to FIG. 1 , a urinary catheter tube 20 is generally formed as an elongated hollow member having a tubular wall 22 surrounding a hollow interior 24 which forms a drainage passage through which bodily fluid may be drained from the bladder. An inner surface 26 of the tubular wall 22 forms a lumen surface around the drainage passage. The catheter tube 20 includes a proximal end 28 and a distal end 30 opposite to the proximal end 28. One or more eyelets or drainage openings 32 are formed at or near the proximal end 28 which facilitate fluid communication from the bladder into the hollow interior 24.
[0015] One or more grooves 50 may be formed in the inner surface 26. For example, the one or more grooves 50 may include a plurality of discretely formed grooves and / or one or more spiral grooves recessed from the inner surface 26. The one or more grooves 50 are configured to provide a selected level of flexibility of the catheter tube 20. Thus, the flexibility of the catheter tube 20 may be varied by varying the configuration of the one or more grooves 50 during manufacture.
[0016] For example, the dimensions (depth, width), shape, frequency andAttorney Docket: 3400-0349 (821 P) spacing may be varied during manufacture to vary the flexibility of the catheter tube 20. In various embodiments, the one or more grooves 50 may be formed having a depth not more than about 60% of the thickness of the tubular wall 22. Grooves formed in this manner allow for flexibility of the catheter tube 20 while remaining suitably strong and rigid. The catheter tube 20 become more flexible as the depth increases. The catheter tube 20 may also become more flexible by increasing a width of the one or more grooves 50. It will be appreciated that the width of a groove extends in the same direction as the length of the catheter tube 20.
[0017] Each of the grooves 50 may be formed having the same dimensions. Alternatively, the dimensions of the grooves 50 may be varied depending on a selected level of flexibility along a length of the catheter tube 20. For example, the grooves 50 may be formed having a first depth along length segment of the catheter tube 20 where more flexibility may be beneficial and a second depth, less than the first depth, along another length segment of the tube 20. Additional grooves may be provided having different dimensions as well. In other examples, the depth or width of the grooves may gradually increase or decrease along a length of the catheter tube 20 to gradually change the flexibility of the tube 20. In an embodiment where the one or more grooves 50 is provided as a spiral groove, the dimensions may remain constant along the length of the catheter tube 20 or may be varied in a manner similar to that described above with respect to the plurality of grooves 50. Alternatively, multiple spiral grooves could be provided having different dimensions.
[0018] The one or more grooves 50 may be formed having different cross- sectional shapes as well. In non-limiting examples, the one or more grooves 50 may have a triangular, semi-circular, or rectangular cross-section. However, other suitable cross-sectional shapes may be used as well, such as a U-shape or other shape including an arced section, or a shape which includes a portion of a polygonal shape.
[0019] Each of the grooves 50 may be formed having the same cross- sectional shape. Alternatively, the shape of the grooves 50 may be varied depending on a selected level of flexibility along a length of the catheter tube 20.Attorney Docket: 3400-0349 (821 P)For example, the grooves 50 may have first shape which tends to increase flexibility along a length segment of the catheter tube 20 where increased flexibility may be beneficial and a second shape, which tends to provide less flexibility than the first shape, along another length segment of the catheter tube 20 where less flexibility may be beneficial. Additional grooves may be provided having different shapes as well. In an embodiment where the one more grooves 50 is provided as a spiral, the cross-sectional shape of the spiral may be varied in the manner above to provide different levels of flexibility along the length of the catheter tube 20. Alternatively, multiple spiral grooves could be provided having different shapes.
[0020] The frequency or spacing between adjacent grooves 50 may provide different levels of flexibility as well. For example, grooves 50 arranged along the length of the tube 20 having a relatively high frequency (or relatively small spacing between adjacent grooves) may provide greater flexibility to the tube 20 than grooves 50 arranged along the length of the tube 20 having a relatively low frequency (or relatively large spacing between adjacent grooves).
[0021] For example, the grooves 50 may be formed having a first spacing between adjacent grooves along length segment of the catheter tube 20 where more flexibility may be beneficial and a second spacing, greater than the first spacing, along another length segment of the tube 20 where less flexibility may be beneficial. Additional grooves may be provided having different spacing as well. In other examples, the spacing between the grooves may gradually increase or decrease along a length of the catheter tube 20 to gradually change the flexibility of the tube 20. In an embodiment where the one or more grooves 50 is provided as a spiral groove, the pitch may be constant or may be varied in a manner similar to varied spacing between grooves described above. Alternatively, multiple spiral grooves could be provided having different pitches.
[0022] A selected flexibility of the catheter tube 20 may thus be provided by forming the one or more grooves 50 to have dimensions, a shape and spacing which provided the selected flexibility. It will be appreciated that the flexibility of the catheter tube 20 may be varied by varying a single one of the dimensions, shapes and spacing of the grooves 50. It will be further appreciated that theAttorney Docket: 3400-0349 (821 P) flexibility may be varied by varying any combination of the dimensions, shapes and spacing of the grooves 50.
[0023] In further examples, the dimensions and / or shape of a groove 50 may be varied in a circumferential direction, which could provide different flexibility of the catheter tube 20 depending on the direction of bending. In some examples, a groove 50 may extend continuously around the inner surface 26 such that the groove 50 is substantially circular or ring shaped. In some examples, a groove 50 may extend partially but not completely around in the inner surface 54, forming a groove segment. In other examples, a groove 50 may be formed by one or more circumferentially spaced groove segments around the inner surface 26. In some examples, the groove segments may be aligned in the circumferential direction, while in other examples, the groove segments may be staggered (i.e. , offset in the length direction of the tube 20).
[0024] The flexibility of the catheter tube may be selected by varying other characteristics as well. For example, the material from which the catheter tube 20 is formed, a diameter of the catheter tube, and a thickness of the tubular wall 22 may all affect flexibility, and can be selected during manufacture. It will be appreciated that various combinations of the above are envisioned as well to provide a selected flexibility.
[0025] By forming the one or more grooves 50 on the inner surface 26, flexibility may be provided while an outer surface 34 of the tubular wall 22 can be a smooth surface. The smooth outer surface 34 may limit resistance when inserting through the urethra, and thus, may improve ease of insertion and user comfort. In addition, with a smooth outer surface, the likelihood of pinching the urethra when flexing may be reduced or eliminated. Further, as shown in FIG. 3, the smooth outer surface 34 may be easily coated to further improve ease of insertion and user comfort. In some examples, the coating 36 may also be lubricous so as to ease advancement and withdrawal of the tube 20 into and from the urethra. The catheter tube 20 may include a lubricous hydrophilic coating 36 disposed on the outer surface 34 of the catheter tube 20 (or tubular wall 22), or the tube may be lubricated with a gel-type lubricant that is applied to the outer surface 34 of the catheter tube.Attorney Docket: 3400-0349 (821 P)
[0026] The catheter tube 20 may have a first length segment 38 extending from the proximal end 28 to an intermediate position 42. Each of the one or more grooves 50 may be positioned within the first length segment 38. A second length segment 40 extends from the intermediate position 42 to the distal end 30. The inner surface 26 in the second length segment 40 may be substantially smooth and free of the one or more grooves 50. That is, the one or more grooves 50 are not formed in the second length segment 40.
[0027] Referring to FIG. 2, a catheter tube 20 according to the embodiments herein may flex or bend due, in part, to the one or more grooves 50. In this manner, the catheter tube 20 may navigate around strictures and / or bends in the urethra during insertion. In one embodiment, the one or more grooves 50 may be arranged such that the catheter tube 20 is symmetrically flexible completely around a longitudinal axis 60 of the catheter tube 20. In other examples, the catheter tube 20 may be symmetrically flexible around a portion of longitudinal axis 60. In still other embodiments, the catheter tube 20 may be flexible around part of, or the entire longitudinal axis 60, and the flexibility may vary depending on the direction of bending. It will be appreciated that flexing or bending of the catheter tube 20 generally occurs along a portion of the first length segment 38 due to the one or grooves 50 in the first length segment 38.
[0028] In some examples, the flexibility of the catheter tube 20 may vary along the length first length segment 38. For instance, the one or more grooves 50 may be arranged at one section to provide a first flexibility and at a second section to provide a second flexibility, different from the first flexibility. Additional sections of different flexibility, or more than one section having the same flexibility as another may be formed in other examples.
[0029] With reference to FIG. 4, according to various examples, the drainage openings 32 can be varied in size and one or more of the drainage openings 32 can be located in corresponding one or more grooves 50. In this manner, bodily fluid may be received in the catheter tube 20 via a combined drainage opening 32 and groove 50. Alternatively or in addition, one or more of the drainage openings 32 may be positioned between grooves 50. Thus, in various embodiments, one or more drainage openings 32 may be located at aAttorney Docket: 3400-0349 (821 P) corresponding one or more groove 50, located between the grooves 50, and / or have at least one opening 32 located at a groove 50 and at least one other opening 32 located between the grooves 50. In further examples, a drainage opening 32 may be provided at the proximal end 28, i.e. , the axial or terminal end of the catheter tube 20. In the examples of FIGS. 5a-5e, one or more drainage openings 32 may be formed in the circumferential direction of the groove 50.
[0030] The catheter tube 20 can be manufactured using a variety of suitable processes. For example, the grooves 50 may be formed by die punching as the tube 20 is being extruded or co-extruded.
[0031] Accordingly, in the present embodiments, a catheter tube 20 may be provided with a smooth, coated outer surface 34 to reduce friction I resistance between the outer surface and an inner surface of the urethra, which may improve ease of insertion and user comfort. In addition, the catheter tube 20 is formed having a suitable degree of flexibility by including one or more grooves formed in the lumen (inner) surface of the tubular wall 22. By forming the one or more grooves 50 in the lumen surface 26, the outer surface 34 may remain smooth, i.e., formed without grooves, to provide ease of insertion and user comfort advantages of a smooth outer surface 34. In addition, by forming the one or more grooves 50 on the inner surface 26, pinching of the urethra by the grooves 50 when flexing is avoided.
[0032] It will be understood that the embodiments described above are illustrative of some of the applications of the principles of the present subject matter. Numerous modifications may be made by those skilled in the art without departing from the spirit and scope of the claimed subject matter, including those combinations of features that are individually disclosed or claimed herein. For these reasons, the scope hereof is not limited to the above description but is as set forth in the following claims, and it is understood that claims may be directed to the features hereof, including as combinations of features that are individually disclosed or claimed herein.
Claims
Attorney Docket: 3400-0349 (821 P)CLAIMS1 . A urinary catheter tube comprising: a tubular wall having a hollow interior, a smooth outer surface and inner surface surrounding the hollow interior, wherein a thickness of the tubular wall extends from the smooth outer surface to the inner surface; one or more grooves formed in the inner surface, the one or more grooves having a shape and a depth extending into the thickness of the tubular wall, the one or more grooves configured to provide a selected flexibility; and one or more drainage openings extending through the tubular wall.
2. The urinary catheter tube of claim 1 , wherein the tubular wall has a proximal end and a distal end opposite to the proximal end, a first length segment extending from the proximal end and a second length segment extending from the first length segment to the distal end, wherein the one or more grooves are formed in the inner surface of the first length segment and not in the second length segment.
3. The urinary catheter tube of claim 1 , wherein the one or more grooves include a plurality of grooves.
4. The urinary catheter tube of claim 3, wherein the grooves are equally spaced from one another.
5. The urinary catheter tube of claim 1 , wherein the one or more grooves includes a spiral shaped groove.
6. The urinary catheter tube of claim 1 , wherein the one or more grooves have a depth up to 60% of the thickness of the tubular wall.
7. The urinary catheter tube of claim 1 , wherein at least one drainage opening is disposed at a proximal terminal end of the tubular wall.
8. The urinary catheter tube of claim 1 , wherein a drainage opening of the one or more drainage openings is disposed in fluid communication with a groove of theAttorney Docket: 3400-0349 (821 P) one or more grooves, such that the drainage opening and the groove extend through the thickness of the tubular wall.
9. The urinary catheter tube of claim 1 , wherein the one or more drainage openings includes at least one drainage opening between adjacent grooves and at least one other drainage opening is positioned at a groove.
10. The urinary catheter tube of any of claims 1 -9, wherein the one or more grooves has a triangular cross-section.11 . The urinary catheter tube of any of claims 1 -9, wherein the one or more grooves has a rectangular cross-section.
12. The urinary catheter tube of any of claims 1 -9, wherein the groove has a semi-circular cross-section.
13. The urinary catheter tube of any of claims 1 -12, further comprising a coating on the smooth outer surface.
14. The urinary catheter of claim 3, wherein the plurality of grooves includes first section grooves providing a first flexibility of the tubular wall and a second section grooves providing a second flexibility of the tubular wall.
15. The urinary catheter of claim 14, wherein the first flexibility and second flexibility are the same.
16. The urinary catheter of claim 14, wherein the first flexibility and second flexibility and different.
17. The urinary catheter of claim 1 , wherein the one or more grooves are configured to provide symmetric flexibility about a longitudinal axis of the tubular wall.
18. The urinary catheter of claim 1 , wherein the one or more grooves are configured to provide a selected flexibility around a longitudinal axis of the tubular wall.Attorney Docket: 3400-0349 (821 P)19. The urinary catheter of claim 1 , wherein the one or more drainage openings include a plurality of drainage openings disposed in communication with a groove of the one or more grooves around a circumference of the groove.