URETERAL STENT AND RETRIEVAL MEANS

Abstract

The described invention provides a ureteral stent device comprising a tubular structure comprising a proximal end and a distal end. The proximal end comprises a magnet, a magnetic tip, a magnetic coating, a magnetic metal, or a magnetic alloy. The distal end comprises a tapered tip and can form any one of a J-curl, a j-shape, or a pigtail loop for securing the distal end in a kidney. The proximal end is not secured in the bladder and terminates in the ureter.

Claims

1. A ureteral stent device, comprising: a tubular structure comprising a stent body, a proximal end and a distal end, wherein: the stent body comprises a first diameter and a second diameter forming a hollow tubular structure wherein the second diameter is greater than the first diameter; the distal end comprises a tip capable of forming a curl for securing the distal end in a kidney; the proximal end comprises a third diameter and a material having magnetic properties; and the proximal end terminates in a ureter.

2. The ureteral stent device of claim 1, wherein the proximal end comprises at least one of a magnet, a magnetic tip, a magnetic coating, a magnetic metal or a magnetic alloy.

3. The ureteral stent device of claim 1, wherein the proximal end comprises at least one of a neodymium iron baron magnet, cobalt-chromium, or a biocompatible magnet.

4. The ureteral stent device of claim 1, wherein the distal end is tapered.

5. The ureteral stent device of claim 1, wherein the proximal end is coated in a biocompatible coating capable of reducing encrustation.

6. The ureteral stent device of claim 5, wherein the coating comprises at least one of Teflon, titanium, heparin, phosphorylcholine, antibiotic, carbon, hyaluronic acid, triclosan, silver, gendine, chitosan, salicylic acid, or hydrogel.

7. The ureteral stent device of claim 1, wherein the proximal end is fixated to the stent body by at least one of a waterproof adhesive, polyurethane glue, a clip mechanism, a screwing mechanism, welding, soldering, taping, or inserting.

8. The ureteral stent device of claim 1, wherein the third diameter is greater or equal to the second diameter.

9. The ureteral stent device of claim 1, wherein the ureteral stent device is retrieved from the ureter with a stent retrieval tool, the stent retrieval device comprising a first end capable of making contact with the proximal end of the ureteral stent device.

10. The ureteral stent device of claim 9, wherein the stent retrieval tool comprises a magnet at the first end.

11. The ureteral stent device of claim 10, wherein the magnet comprises a coating capable of reducing encrustation.

12. The ureteral stent device of claim 11, wherein the coating comprises at least one of Teflon, titanium, heparin, phosphorylcholine, antibiotic, carbon, hyaluronic acid, triclosan, silver, gendine, chitosan, salicylic acid, or hydrogel.

13. The ureteral stent device of claim 9, wherein the stent retrieval tool comprises a rod at the first end.

14. The ureteral stent device of claim 13, wherein the rod comprises at least one of steel, stainless steel, iron, nickel, cobalt, cobalt-chromium, rare earth metals or a rod capable of being magnetized.

15. The ureteral stent device of claim 13, wherein the rod is electromagnetically charged and contacted to the proximal end of the ureteral stent device to remove ureteral stent the device from the ureter.

16. The ureteral stent device of claim 9, wherein the first end comprises a fourth diameter, wherein the fourth diameter is less than or equal to the third diameter.

17. A ureteral stent device, comprising: a tubular structure comprising a stent body, a proximal end, a distal end, a cap and an attachment device, wherein: the stent body comprises an first diameter and a second diameter forming a hollow tubular structure hollow where the second diameter is greater than the first diameter; the distal end comprises a tip capable of forming a curl for securing the distal end in a kidney; the proximal end is attached to the cap via the attachment device; the proximal end terminates in a ureter; and at least a part of the cap is situated in a bladder.

18. The ureteral stent device of claim 17, wherein the attachment device comprises one of a string or a flexible polymer.

19. The ureteral stent device of claim 17, wherein the cap is coated in a biocompatible coating capable of reducing encrustation.

20. The ureteral stent device of claim 19, wherein the coating comprises at least one of Teflon, titanium, heparin, phosphorylcholine, antibiotic, carbon, hyaluronic acid, triclosan, silver, gendine, chitosan, salicylic acid, or hydrogel.

21. The ureteral stent device of claim 17, wherein the cap comprises a porous-dome shape.

22. The ureteral stent device of claim 21, wherein the shape allows for a retrieval tool to be attached to pores in the cap and to remove the ureteral stent device from the ureter via the urethra.

23. The ureteral stent device of claim 17, wherein the cap is prevents the ureteral stent device from receding into the ureter.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0035] FIG. 1 shows an illustrative view of ureteral stents; (from Dyer, Raymond B., MD, “Complications of Ureteral Stent Placement” Radio Graphics, Volume 22-No. 5, September-October 2002: p. 1007);

[0036] FIG. 2 shows an illustrative view of a ureteral stent in the human body; (from UrologySanAntonio.com, Accessed January 2019);

[0037] FIGS. 3A-3B show an illustrative embodiment of the ureteral stent device 300 of the present disclosure;

[0038] FIG. 4 shows an illustrative embodiment of the ureteral stent device 300 of the present disclosure in a human body.

[0039] FIG. 5 shows an illustration of the ureteral stent device 300 of the present disclosure in comparison with a traditional “double J-curl” ureteral stent 400;

[0040] FIG. 6 shows an illustrative view of an electromagnet of the present disclosure comprising copper wire wound down the long axis of a steel rod;

[0041] FIG. 7 shows equations for force excerted by a magnetic field;

[0042] FIG. 8 shows equations for a closed magnetic circuit;

[0043] FIG. 9 is a graph showing the force required to separate the ureteral stent device 300 and a stent retrieval tool, of the present disclosure;

[0044] FIG. 10 is a graph showing projected results for a flow rate test using the ureteral stent device 300, of the present disclosure;

[0045] FIG. 11 is a table showing the magnetic properties of cobalt-chromium;

[0046] FIG. 12 is a illustrative embodiment of the a cobalt-chromium proximal end of the present disclosure;

[0047] FIG. 13 shows an illustrative embodiment of the ureteral stent device 700 of the present disclosure; and

[0048] FIGS. 14A and 14B show illustration of a closer view of the cap 716 and the attachment device 718 of the ureteral stent device 700.

DETAILED DESCRIPTION OF THE INVENTION

Glossary

[0049] The term “proximal” as used herein, refers to the state of being situated next to or nearest the point of attachment or origin.

[0050] The term “distal” as used herein, refers to the state of being situated away from the point of attachment or origin

[0051] The term “tapered” as used herein, means being diminished or reduced in thickness towards the end.

[0052] The term “biocompatible” as used herein, means causing no clinically relevant tissue irritation, injury, toxic reaction, or immunologic reaction to human tissue based on a clinical risk/benefit assessment.

[0053] The present disclosure relates to a ureteral stent device and removal means, as discussed in detail below in connection with FIGS. 3-14.

[0054] FIG. 3A shows an exemplary and non-limiting example of an ureteral stent device 300 of the described invention. The ureteral stent device 300 of the described invention comprises a proximal end 302, a stent body 304, and a distal end 306. The stent body 304 comprises a tubular structure comprising an inner diameter d.sub.1 and an outer diameter d.sub.2, making the stent body 304 hollow. The hollow body allows urine to flow through ureteral stent device 300. The proximal end 302 comprises a magnet, a magnetic tip, a magnetic coating, a magnetic metal, a magnetic alloy, etc. It should be understood that the proximal end 302 is hollow to allow urine to flow through the ureteral stent device 300. By way of example, the magnet is a neodymium iron baron magnet. However, those skilled in the art would understand that the proximal end 302 can comprise any other biocompatible magnet. The magnet can be coated with a biocompatible coating, such as, for example, Teflon, titanium, or any other coating effective to prevent or reduce encrustation (e.g., heparin, phosphorylcholine, antibiotic, carbon, hyaluronic acid, triclosan, silver, gendine, chitosan, salicylic acid, hydrogel, etc.). The magnet can be fixated to the proximal end 302. In an embodiment, the magnet is fixated to the proximal end using a waterproof adhesive, such as but not limited to, polyurethane glue. Those skilled in the art would understand that other fixating methods can be used, such, as but not limited to, a clip mechanism, a screwing mechanism, welding, soldering, taping, inserting, etc.

[0055] The ureteral stent device 300 is of length l.sub.1, with the distal end 306 curled. The distal end 306, when curled, is of length l.sub.2. According to some embodiments, the length of the stent body 304 and the proximal end 302 (i.e. l.sub.1-l.sub.2) does not exceed the length of the human ureter in order to keep material out of the bladder. The average length of a human ureter is generally 25 cm-30 cm. According to some embodiments, the length of the stent body 304 and the proximal end 302 ranges from 1 cm to 50 cm. According to some embodiments, the length of the stent body 304 and the proximal end 302 is at least 1 cm. According to some embodiments, the length of the stent body 304 and the proximal end 302 is at least 2 cm. According to some embodiments, the length of the stent body 304 and the proximal end 302 is at least 3 cm. According to some embodiments, the length of the stent body 304 and the proximal end 302 is at least 4 cm. According to some embodiments, the length of the stent body 304 and the proximal end 302 is at least 5 cm. According to some embodiments, the length of the stent body 304 and the proximal end 302 is at least 6 cm. According to some embodiments, the length of the stent body 304 and the proximal end 302 is at least 7 cm. According to some embodiments, the length of the stent body 304 and the proximal end 302 is at least 8 cm. According to some embodiments, the length of the stent body 304 and the proximal end 302 is at least 9 cm. According to some embodiments, the length of the stent body 304 and the proximal end 302 is at least 10 cm. According to some embodiments, the length of the stent body 304 and the proximal end 302 is at least 11 cm. According to some embodiments, the length of the stent body 304 and the proximal end 302 is at least 12 cm. According to some embodiments, the length of the stent body 304 and the proximal end 302 is at least 13 cm. According to some embodiments, the length of the stent body 304 and the proximal end 302 is at least 14 cm. According to some embodiments, the length of the stent body 304 and the proximal end 302 is at least 15 cm. According to some embodiments, the length of the stent body 304 and the proximal end 302 is at least 16 cm. According to some embodiments, the length of the stent body 304 and the proximal end 302 is at least 17 cm. According to some embodiments, the length of the stent body 304 and the proximal end 302 is at least 18 cm. According to some embodiments, the length of the stent body 304 and the proximal end 302 is at least 19 cm. According to some embodiments, the length of the stent body 304 and the proximal end 302 is at least 20 cm. According to some embodiments, the length of the stent body 304 and the proximal end 302 is at least 21 cm. According to some embodiments, the length of the stent body 304 and the proximal end 302 is at least 22 cm. According to some embodiments, the length of the stent body 304 and the proximal end 302 is at least 23 cm. According to some embodiments, the length of the stent body 304 and the proximal end 302 is at least 24 cm. According to some embodiments, the length of the stent body 304 and the proximal end 302 is at least 25 cm. According to some embodiments, the length of the stent body 304 and the proximal end 302 is at least 26 cm. According to some embodiments, the length of the stent body 304 and the proximal end 302 is at least 27 cm. According to some embodiments, the length of the stent body 304 and the proximal end 302 is at least 28 cm. According to some embodiments, the length of the stent body 304 and the proximal end 302 is at least 29 cm. According to some embodiments, the length of the stent body 304 and the proximal end 302 is at least 30 cm. According to some embodiments, the length of the stent body 304 and the proximal end 302 is at least 31 cm. According to some embodiments, the length of the stent body 304 and the proximal end 302 is at least 32 cm. According to some embodiments, the length of the stent body 304 and the proximal end 302 is at least 33 cm. According to some embodiments, the length of the stent body 304 and the proximal end 302 is at least 34 cm. According to some embodiments, the length of the stent body 304 and the proximal end 302 is at least 35 cm. According to some embodiments, the length of the stent body 304 and the proximal end 302 is at least 36 cm. According to some embodiments, the length of the stent body 304 and the proximal end 302 is at least 37 cm. According to some embodiments, the length of the stent body 304 and the proximal end 302 is at least 38 cm. According to some embodiments, the length of the stent body 304 and the proximal end 302 is at least 39 cm. According to some embodiments, the length of the stent body 304 and the proximal end 302 is at least 40 cm. According to some embodiments, the length of the stent body 304 and the proximal end 302 is at least 41 cm. According to some embodiments, the length of the stent body 304 and the proximal end 302 is at least 42 cm. According to some embodiments, the length of the stent body 304 and the proximal end 302 is at least 43 cm. According to some embodiments, the length of the stent body 304 and the proximal end 302 is at least 44 cm. According to some embodiments, the length of the stent body 304 and the proximal end 302 is at least 45 cm. According to some embodiments, the length of the stent body 304 and the proximal end 302 is at least 46 cm. According to some embodiments, the length of the stent body 304 and the proximal end 302 is at least 47 cm. According to some embodiments, the length of the stent body 304 and the proximal end 302 is at least 48 cm. According to some embodiments, the length of the stent body 304 and the proximal end 302 is at least 49 cm. According to some embodiments, the length of the stent body 304 and the proximal end 302 is at least 50 cm.

[0056] The minimum diameter of a human ureter is generally 3 mm, but can exceed this minimum diameter. (Zelenko, N, et al. “Normal Ureter Size on Unenhanced Helical CT.” Current Neurology and Neuroscience Reports, U.S. National Library of Medicine, April 2004). For example, the diameter of the proximal end 302 (d.sub.3) and the diameter of the stent body 304 (d.sub.2) does not exceed a patient's ureter diameter.

[0057] According to some embodiments, the outer diameter of the proximal end 302 (d.sub.2) ranges from 1.0 mm to 5.0 mm. According to some embodiments, d.sub.2 is at least 1.0 mm. According to some embodiments, d.sub.2 is at least 1.1 mm. According to some embodiments, d.sub.2 is at least 1.2 mm. According to some embodiments, d.sub.2 is at least 1.3 mm. According to some embodiments, d.sub.2 is at least 1.4 mm. According to some embodiments, d.sub.2 is at least 1.5 mm. According to some embodiments, d.sub.2 is at least 1.6 mm. According to some embodiments, d.sub.2 is at least 1.7 mm. According to some embodiments, d.sub.2 is at least 1.8 mm. According to some embodiments, d.sub.2 is at least 1.9 mm. According to some embodiments, d.sub.2 is at least 2.0 mm. According to some embodiments, d.sub.2 is at least 2.0 mm. According to some embodiments, d.sub.2 is at least 2.1 mm. According to some embodiments, d.sub.2 is at least 2.2 mm. According to some embodiments, d.sub.2 is at least 2.3 mm. According to some embodiments, d.sub.2 is at least 2.4 mm. According to some embodiments, d.sub.2 is at least 2.5 mm. According to some embodiments, d.sub.2 is at least 2.6 mm. According to some embodiments, d.sub.2 is at least 2.7 mm. According to some embodiments, d.sub.2 is at least 2.8 mm. According to some embodiments, d.sub.2 is at least 2.9 mm. According to some embodiments, d.sub.2 is at least 3.0 mm. According to some embodiments, d.sub.2 is at least 3.1 mm. According to some embodiments, d.sub.2 is at least 3.2 mm. According to some embodiments, d.sub.2 is at least 3.3 mm. According to some embodiments, d.sub.2 is at least 3.4 mm. According to some embodiments, d.sub.2 is at least 3.5 mm. According to some embodiments, d.sub.2 is at least 3.6 mm. According to some embodiments, d.sub.2 is at least 3.7 mm. According to some embodiments, d.sub.2 is at least 3.8 mm. According to some embodiments, d.sub.2 is at least 3.9 mm. According to some embodiments, d.sub.2 is at least 4.0 mm. According to some embodiments, d.sub.2 is at least 4.1 mm. According to some embodiments, d.sub.2 is at least 4.2 mm. According to some embodiments, d.sub.2 is at least 4.3 mm. According to some embodiments, d.sub.2 is at least 4.4 mm. According to some embodiments, d.sub.2 is at least 4.5 mm. According to some embodiments, d.sub.2 is at least 4.6 mm. According to some embodiments, d.sub.2 is at least 4.7 mm. According to some embodiments, d.sub.2 is at least 4.8 mm. According to some embodiments, d.sub.2 is at least 4.9 mm. According to some embodiments, d.sub.2 is at least 5.0 mm.

[0058] According to some embodiments, the inner diameter d.sub.1 of the proximal end 302 (d.sub.1) ranges from 0.1 mm to 4.0 mm. According to some embodiments, d.sub.1 is at least 0.1 mm. According to some embodiments, d.sub.1 is at least 0.2 mm. According to some embodiments, d.sub.1 is at least 0.3 mm. According to some embodiments, d.sub.1 is at least 0.4 mm. According to some embodiments, d.sub.1 is at least 0.5 mm. According to some embodiments, d.sub.1 is at least 0.6 mm. According to some embodiments, d.sub.1 is at least 0.7 mm. According to some embodiments, d.sub.1 is at least 0.8 mm. According to some embodiments, d.sub.1 is at least 0.9 mm. According to some embodiments, d.sub.1 is at least 1.0 mm. According to some embodiments, d.sub.1 is at least 1.1 mm. According to some embodiments, d.sub.1 is at least 1.2 mm. According to some embodiments, d.sub.1 is at least 1.3 mm. According to some embodiments, d.sub.1 is at least 1.4 mm. According to some embodiments, d.sub.1 is at least 1.5 mm. According to some embodiments, d.sub.1 is at least 1.6 mm. According to some embodiments, d.sub.1 is at least 1.7 mm. According to some embodiments, d.sub.1 is at least 1.8 mm. According to some embodiments, d.sub.1 is at least 1.9 mm. According to some embodiments, d.sub.1 is at least 2.0 mm. According to some embodiments, d.sub.1 is at least 2.0 mm. According to some embodiments, d.sub.1 is at least 2.1 mm. According to some embodiments, d.sub.1 is at least 2.2 mm. According to some embodiments, d.sub.1 is at least 2.3 mm. According to some embodiments, d.sub.1 is at least 2.4 mm. According to some embodiments, d.sub.1 is at least 2.5 mm. According to some embodiments, d.sub.1 is at least 2.6 mm. According to some embodiments, d.sub.1 is at least 2.7 mm. According to some embodiments, d.sub.1 is at least 2.8 mm. According to some embodiments, d.sub.1 is at least 2.9 mm. According to some embodiments, d.sub.1 is at least 3.0 mm. According to some embodiments, d.sub.1 is at least 3.1 mm. According to some embodiments, d.sub.1 is at least 3.2 mm. According to some embodiments, d.sub.1 is at least 3.3 mm. According to some embodiments, d.sub.1 is at least 3.4 mm. According to some embodiments, d.sub.1 is at least 3.5 mm. According to some embodiments, d.sub.1 is at least 3.6 mm. According to some embodiments, d.sub.1 is at least 3.7 mm. According to some embodiments, d.sub.1 is at least 3.8 mm. According to some embodiments, d.sub.1 is at least 3.9 mm. According to some embodiments, d.sub.1 is at least 4.0 mm.

[0059] FIG. 3B shows exemplary and non-limiting examples of the proximal end 302 of the ureteral stent device 300. The proximal end 302 comprises a cylindrical magnet comprising a diameter d.sub.3 and a length of l.sub.3. According to some embodiments, d.sub.3 ranges from 1.0 mm to 5.0 mm. According to some embodiments, d.sub.3 is at least 1.0 mm. According to some embodiments, d.sub.3 is at least 1.1 mm. According to some embodiments, d.sub.3 is at least 1.2 mm. According to some embodiments, d.sub.3 is at least 1.3 mm. According to some embodiments, d.sub.3 is at least 1.4 mm. According to some embodiments, d.sub.3 is at least 1.5 mm. According to some embodiments, d.sub.3 is at least 1.6 mm. According to some embodiments, d.sub.3 is at least 1.7 mm. According to some embodiments, d.sub.3 is at least 1.8 mm. According to some embodiments, d.sub.3 is at least 1.9 mm. According to some embodiments, d.sub.3 is at least 2.0 mm. According to some embodiments, d.sub.3 is at least 2.0 mm. According to some embodiments, d.sub.3 is at least 2.1 mm. According to some embodiments, d.sub.3 is at least 2.2 mm. According to some embodiments, d.sub.3 is at least 2.3 mm. According to some embodiments, d.sub.3 is at least 2.4 mm. According to some embodiments, d.sub.3 is at least 2.5 mm. According to some embodiments, d.sub.3 is at least 2.6 mm. According to some embodiments, d.sub.3 is at least 2.7 mm. According to some embodiments, d.sub.3 is at least 2.8 mm. According to some embodiments, d.sub.3 is at least 2.9 mm. According to some embodiments, d.sub.3 is at least 3.0 mm. According to some embodiments, d.sub.3 is at least 3.1 mm. According to some embodiments, d.sub.3 is at least 3.2 mm. According to some embodiments, d.sub.3 is at least 3.3 mm. According to some embodiments, d.sub.3 is at least 3.4 mm. According to some embodiments, d.sub.3 is at least 3.5 mm. According to some embodiments, d.sub.3 is at least 3.6 mm. According to some embodiments, d.sub.3 is at least 3.7 mm. According to some embodiments, d.sub.3 is at least 3.8 mm. According to some embodiments, d.sub.3 is at least 3.9 mm. According to some embodiments, d.sub.3 is at least 4.0 mm. According to some embodiments, d.sub.3 is at least 4.1 mm. According to some embodiments, d.sub.3 is at least 4.2 mm. According to some embodiments, d.sub.3 is at least 4.3 mm. According to some embodiments, d.sub.3 is at least 4.4 mm. According to some embodiments, d.sub.3 is at least 4.5 mm. According to some embodiments, d.sub.3 is at least 4.6 mm. According to some embodiments, d.sub.3 is at least 4.7 mm. According to some embodiments, d.sub.3 is at least 4.8 mm. According to some embodiments, d.sub.3 is at least 4.9 mm. According to some embodiments, d.sub.3 is at least 5.0 mm.

[0060] According to some embodiments, l.sub.3 ranges from 1.0 mm to 5.0 mm. According to some embodiments, l.sub.3 is at least 1.0 mm. According to some embodiments, l.sub.3 is at least 1.1 mm. According to some embodiments, l.sub.3 is at least 1.2 mm. According to some embodiments, l.sub.3 is at least 1.3 mm. According to some embodiments, l.sub.3 is at least 1.4 mm. According to some embodiments, l.sub.3 is at least 1.5 mm. According to some embodiments, l.sub.3 is at least 1.6 mm. According to some embodiments, l.sub.3 is at least 1.7 mm. According to some embodiments, l.sub.3 is at least 1.8 mm. According to some embodiments, l.sub.3 is at least 1.9 mm. According to some embodiments, l.sub.3 is at least 2.0 mm. According to some embodiments, l.sub.3 is at least 2.0 mm. According to some embodiments, l.sub.3 is at least 2.1 mm. According to some embodiments, l.sub.3 is at least 2.2 mm. According to some embodiments, l.sub.3 is at least 2.3 mm. According to some embodiments, l.sub.3 is at least 2.4 mm. According to some embodiments, l.sub.3 is at least 2.5 mm. According to some embodiments, l.sub.3 is at least 2.6 mm. According to some embodiments, l.sub.3 is at least 2.7 mm. According to some embodiments, l.sub.3 is at least 2.8 mm. According to some embodiments, l.sub.3 is at least 2.9 mm. According to some embodiments, l.sub.3 is at least 3.0 mm. According to some embodiments, l.sub.3 is at least 3.1 mm. According to some embodiments, l.sub.3 is at least 3.2 mm. According to some embodiments, l.sub.3 is at least 3.3 mm. According to some embodiments, l.sub.3 is at least 3.4 mm. According to some embodiments, l.sub.3 is at least 3.5 mm. According to some embodiments, l.sub.3 is at least 3.6 mm. According to some embodiments, l.sub.3 is at least 3.7 mm. According to some embodiments, l.sub.3 is at least 3.8 mm. According to some embodiments, l.sub.3 is at least 3.9 mm. According to some embodiments, l.sub.3 is at least 4.0 mm. According to some embodiments, l.sub.3 is at least 4.1 mm. According to some embodiments, l.sub.3 is at least 4.2 mm. According to some embodiments, l.sub.3 is at least 4.3 mm. According to some embodiments, l.sub.3 is at least 4.4 mm. According to some embodiments, l.sub.3 is at least 4.5 mm. According to some embodiments, l.sub.3 is at least 4.6 mm. According to some embodiments, l.sub.3 is at least 4.7 mm. According to some embodiments, l.sub.3 is at least 4.8 mm. According to some embodiments, l.sub.3 is at least 4.9 mm. According to some embodiments, l.sub.3 is at least 5.0 mm. It should be understood that, according to some embodiments, l.sub.3 ranges from 0.1 mm to 1.0 mm, and according to other embodiments, l.sub.3 ranges from 5 mm to 50 mm.

[0061] FIG. 4 shows an exemplary and non-limiting example of a ureteral stent device 300 of the described invention in a human body. Specifically, FIG. 4 shows the proximal end 302, the stent body 304, and the distal end 306, a kidney 308, a ureter 310, a bladder 312, and a urethra 314. The distal end 306 comprises a tip and can form any one of a J-curl, a j-shape, a pigtail loop, or any other type of curl capable of securing the distal end 306 in the kidney 308. The tip can be tapered. The kidney 308 is used to show a general relation between the kidney entrance and the distal end 306, and is used for illustrative purposes only. Similarly, the bladder 312 is used to show a general relation between the bladder and the proximal end 302, and is used for illustrative purposes only.

[0062] In this embodiment, the proximal end 302 does not enter the bladder 312, and terminates in the ureter 310. This is solely by way of example. In other embodiments, the proximal end 302 can terminal in the bladder 312, or anywhere else along the ureter 310.

[0063] It should be appreciated by those skilled in the art that the proximal end 302 does not comprise a J-curl, and terminates in the ureter 310 or near the entrance of the bladder 312. This reduces patient discomfort, bladder irritation, and encrustation when compared to a more traditional “double J-curl” ureteral stent because the ureteral stent device 300 eliminates material residing in the bladder 312.

[0064] Insertion of the ureteral stent device 300 into the human body can follow current methods and standards required by the FDA. The procedure entails utilizing a guidewire inserted into the urethra 314 which travels to the kidney 308, monitored via fluoroscopy. The stent is then advanced over the guidewire using a stent pusher until the distal J-curl is completely in the kidney. The positioning of the ureteral stent device 300 is then confirmed using fluoroscopy. Once the ureteral stent device 300 is correctly positioned, the guidewire is removed, completing the insertion procedure.

[0065] FIG. 5 shows an illustration of the ureteral stent device 300 in comparison with a traditional “double J-curl” ureteral stent 500. Specifically, the traditional “double J-curl” ureteral stent 500 comprises a J-curl at each end, while the ureteral stent device 300 of the disclosed invention comprises a J-curl on one end, and a magnet on the other end.

[0066] The ureteral stent device 300 can be retrieved by employing a stent retrieval tool. In one example, the stent retrieval tool can comprise a magnet at one end, where a polarity of the magnet at the end of the stent retrieval tool is reactive to the polarity of the magnetic tip of the ureteral stent device 300, meaning a pole of a magnet in space with relatively more electrons is said to have negative polarity, while the pole with relatively fewer electrons is said to have positive polarity. The pole with negative polarity of the proximal end 302 is attracted to the pole with positive polarity of the stent retrieval tool, or vice versa. The magnet can comprise a coating. By way of example, the magnet at the end of the stent retrieval tool can comprise a neodymium iron baron magnet or any other biocompatible magnet and the coating can comprise Teflon, titanium, or any other coating effective to prevent or reduce encrustation. The magnetic end of the stent retrieval tool can be inserted into the urethra 314 and maneuvered to make contact (meaning state or condition of touching or being in immediate proximity) with the magnet at the proximal end 302. Once contact is made, the stent retrieval tool can be used to withdraw the ureteral stent device 300 from the ureter via the urethra 314.

[0067] In another example, the stent retrieval tool utilizes electromagnetic technology. The stent retrieval tool can comprise a metallic rod (e.g., steel, stainless steel, iron, nickel, cobalt, rare earth metals, etc.), or any other suitable rod capable of being magnetized, fixated to a ureteral catheter. The stent retrieval tool can be fixated to the ureteral catheter via an adhesive (e.g., polyurethane glue), a clip mechanism, a screwing mechanism, welding, soldering, taping, inserting, etc. The rod can be electromagnetically charged and contacted to the proximal end of the ureteral stent device 300 to remove the device 300. It is noted that pinching of the ureter wall will not occur when the diameter of the rod is less than the diameter of magnet. According to some embodiments, the diameter of the rod ranges from 1.0 mm to 5.0 mm. According to some embodiments, the diameter of the rod is at least 1.0 mm. According to some embodiments, the diameter of the rod is at least 1.1 mm. According to some embodiments, the diameter of the rod is at least 1.2 mm. According to some embodiments, the diameter of the rod is at least 1.3 mm. According to some embodiments, the diameter of the rod is at least 1.4 mm. According to some embodiments, the diameter of the rod is at least 1.5 mm. According to some embodiments, the diameter of the rod is at least 1.6 mm. According to some embodiments, the diameter of the rod is at least 1.7 mm. According to some embodiments, the diameter of the rod is at least 1.8 mm. According to some embodiments, the diameter of the rod is at least 1.9 mm. According to some embodiments, the diameter of the rod is at least 2.0 mm. According to some embodiments, the diameter of the rod is at least 2.0 mm. According to some embodiments, the diameter of the rod is at least 2.1 mm. According to some embodiments, the diameter of the rod is at least 2.2 mm. According to some embodiments, the diameter of the rod is at least 2.3 mm. According to some embodiments, the diameter of the rod is at least 2.4 mm. According to some embodiments, the diameter of the rod is at least 2.5 mm. According to some embodiments, the diameter of the rod is at least 2.6 mm. According to some embodiments, the diameter of the rod is at least 2.7 mm. According to some embodiments, the diameter of the rod is at least 2.8 mm. According to some embodiments, the diameter of the rod is at least 2.9 mm. According to some embodiments, the diameter of the rod is at least 3.0 mm. According to some embodiments, the diameter of the rod is at least 3.1 mm. According to some embodiments, the diameter of the rod is at least 3.2 mm. According to some embodiments, the diameter of the rod is at least 3.3 mm. According to some embodiments, the diameter of the rod is at least 3.4 mm. According to some embodiments, the diameter of the rod is at least 3.5 mm. According to some embodiments, the diameter of the rod is at least 3.6 mm. According to some embodiments, the diameter of the rod is at least 3.7 mm. According to some embodiments, the diameter of the rod is at least 3.8 mm. According to some embodiments, the diameter of the rod is at least 3.9 mm. According to some embodiments, the diameter of the rod is at least 4.0 mm. According to some embodiments, the diameter of the rod is at least 4.1 mm. According to some embodiments, the diameter of the rod is at least 4.2 mm. According to some embodiments, the diameter of the rod is at least 4.3 mm. According to some embodiments, the diameter of the rod is at least 4.4 mm. According to some embodiments, the diameter of the rod is at least 4.5 mm. According to some embodiments, the diameter of the rod is at least 4.6 mm. According to some embodiments, the diameter of the rod is at least 4.7 mm. According to some embodiments, the diameter of the rod is at least 4.8 mm. According to some embodiments, the diameter of the rod is at least 4.9 mm. According to some embodiments, the diameter of the rod is at least 5.0 mm

[0068] According to some embodiments, the length of the rod ranges from 1.0 cm to 5.0 cm. According to some embodiments, the diameter of the rod is at least 1.0 cm. According to some embodiments, the diameter of the rod is at least 1.1 cm. According to some embodiments, the diameter of the rod is at least 1.2 cm. According to some embodiments, the diameter of the rod is at least 1.3 cm. According to some embodiments, the diameter of the rod is at least 1.4 cm. According to some embodiments, the diameter of the rod is at least 1.5 cm. According to some embodiments, the diameter of the rod is at least 1.6 cm. According to some embodiments, the diameter of the rod is at least 1.7 cm. According to some embodiments, the diameter of the rod is at least 1.8 cm. According to some embodiments, the diameter of the rod is at least 1.9 cm. According to some embodiments, the diameter of the rod is at least 2.0 cm. According to some embodiments, the diameter of the rod is at least 2.0 cm. According to some embodiments, the diameter of the rod is at least 2.1 cm. According to some embodiments, the diameter of the rod is at least 2.2 cm. According to some embodiments, the diameter of the rod is at least 2.3 cm. According to some embodiments, the diameter of the rod is at least 2.4 cm. According to some embodiments, the diameter of the rod is at least 2.5 cm. According to some embodiments, the diameter of the rod is at least 2.6 cm. According to some embodiments, the diameter of the rod is at least 2.7 cm. According to some embodiments, the diameter of the rod is at least 2.8 cm. According to some embodiments, the diameter of the rod is at least 2.9 cm. According to some embodiments, the diameter of the rod is at least 3.0 cm. According to some embodiments, the diameter of the rod is at least 3.1 cm. According to some embodiments, the diameter of the rod is at least 3.2 cm. According to some embodiments, the diameter of the rod is at least 3.3 cm. According to some embodiments, the diameter of the rod is at least 3.4 cm. According to some embodiments, the diameter of the rod is at least 3.5 cm. According to some embodiments, the diameter of the rod is at least 3.6 cm. According to some embodiments, the diameter of the rod is at least 3.7 cm. According to some embodiments, the diameter of the rod is at least 3.8 cm. According to some embodiments, the diameter of the rod is at least 3.9 cm. According to some embodiments, the diameter of the rod is at least 4.0 cm. According to some embodiments, the diameter of the rod is at least 4.1 cm. According to some embodiments, the diameter of the rod is at least 4.2 cm. According to some embodiments, the diameter of the rod is at least 4.3 cm. According to some embodiments, the diameter of the rod is at least 4.4 cm. According to some embodiments, the diameter of the rod is at least 4.5 cm. According to some embodiments, the diameter of the rod is at least 4.6 cm. According to some embodiments, the diameter of the rod is at least 4.7 cm. According to some embodiments, the diameter of the rod is at least 4.8 cm. According to some embodiments, the diameter of the rod is at least 4.9 cm. According to some embodiments, the diameter of the rod is at least 5.0 cm. It should be understood that, according to some embodiments, the diameter of the rod ranges from 0.1 cm to 1.0 cm, and according to other embodiments, the diameter of the rod ranges from 5 cm to 50 cm.

[0069] An exemplary and non-limiting example of a stent retrieval tool using a steel rod will now be discussed. A steel rod has magnetic permeability value of 1.03 Tesla. A Tesla is a unit of magnetic induction or magnetic flux density in the meter-kilogram-second system of physical units. Further, the permeability value combined with the cost of steel makes it an adequate option for the retrieval tool. To produce the electromagnet, copper wire is wound down the long axis of the rod, as seen in FIG. 6. An electric current is then applied to the copper wire to increase the magnetic properties of the steel core, thus creating an electromagnet. To supply the power, a circuit can be used to produce an appropriate voltage and/or electric current to magnetize the steel rod. In one example, the power circuit can consist of a direct current power source, (e.g., AAA battery, AA battery, 9 volt battery, button battery, etc.) connected to a resistor to produce a desired electrical current. For example, a 1.5 volt battery connected to a 0.3k Ohm resistor will output approximately 5 mA to the electromagnet, producing the acceptable magnetic field for stent removal. In another example, the power circuit can consist of an alternating power source connected to a transformer and other components to produce the desired electrical current.

[0070] It is noted that for patient safety, the electrical current produced by a circuit to power the electromagnet is recommended to not exceed approximately 5 mA (milliamperes). This is because an electrical current greater than 5 mA can cause muscle spasms, paralysis, and even cardiac arrest possibly leading to death (“The Fatal Current.” The Case for Stronger Antibiotic Regulation).

[0071] The physician can use an imaging device (e.g., X-ray device, ultrasound device, etc.) to aid the tool in making contact with the proximal end 302. In one embodiment, the stent retrieval tool can comprise an endoscope or any other camera type device. The endoscope can be used to aid a physician in guiding the stent retrieval tool to make contact with the proximal end 302.

[0072] To remove the ureteral stent device, a magnetic pull force of approximately 5 Newtons is recommended. (Wang, Jin, et al. “Preclinical Evaluation of a Newly Designed Ureteral Stent and Magnetic Retrieval Catheter for Minimally Invasive Stent Removal.” Urology, vol. 84, no. 4, 2014, pp. 960-966, doi:10.1016/j.urology.2014.06.024). Magnetization is often characterized by the magnetic flux density. The magnetic flux is a measurement of the total magnetic field which passes through a given area. Identifying the magnetic flux density of the stent retrieval device can determine its dimensions. FIG. 7 shows an equation (Equation 1) to determine a force exerted by the magnetic field. The force, magnetic permeability, and the cross-section area are known, and the equation is solved (Equations 2-5) for the magnetic flux density. By way of example for a neodymium magnet, the magnetic flux density is 2.12 Tesla. It should be noted that as the cross section area decreases, the magnetic flux density increases. As such, those skilled in the art would be able to use Equation 1 to adjust the ureteral stent device to a desired magnetic flux density and cross area.

[0073] FIG. 8 shows an equation (Equation 1) to adjust the dimensions of the electromagnet. In this example, the magnetic flux density, electrical current, permeability of steel, and length are all known values. Therefore, Equation 6 can be rearranged to solve for N, which is the number of turns, as seen in Equations 7-9. The number of turns determined in this example is 11 (Equation 2). It is understood by those skilled in the art that as electrical current decreases, the number of turns increases.

[0074] Experimental results of using the ureteral stent device 300 and using the stent retrieval tool will now be discussed. It is noted that these results are discussed by way of example for illustrative purposes, and are not limiting to the invention discussed herein. In the experiment, the tensile strength required to remove the ureteral stent device 300 using the stent retrieval tool was tested via a Bose ElectroForce 3200 load frame system. The flow of urine through the ureteral stent device 300 was calculated by pumping water at 40° C., which is theoretically equivalent to the viscosity of urine, through the ureteral stent device 300 while a pressure gauge measured inlet and outlet pressures, using Equation 10, below:

[00001]$\begin{array}{cc}\frac{Q*128\mathrm{.Math.}*L}{\pi *D^4}+P_{\mathrm{in}}=P_{\mathrm{out}}& \mathrm{Equation}10\end{array}$

[0075] Where: [0076] Q=Flow rate [m.sup.3/sec], [0077] Poiseuille Flow Constant=128, [0078] μ=viscosity of liquid [Pa*sec] [0079] L=length of the ureteral stent device 300 [m], [0080] D=inner diameter of the ureteral stent device 300 [m], [0081] P in =Pressure at the inlet [Pa], [0082] P.sub.ow=Pressure at outlet [Pa]

[0083] FIG. 9 is a graph showing the force required to separate the ureteral stent device 300 and the stent retrieval tool, and the flow rate of “urine” through the ureteral stent device 300. As shown, the ureteral stent device 300 and the stent retrieval tool separate at 10 Newtons (“N”) of force. A Newton, the SI unit of force, is the amount of force required to make a mass of one kilogram accelerate at a rate of one meter/second.sup.2. Any value less than 5 N would result in failure to remove the stent from the ureter. This provides a factor of safety of two.

[0084] FIG. 10 is a graph showing projected results for a flow rate test using the ureteral stent device 300. Specifically, FIG. 10 shows that urine flow (meaning moving along in a steady, continuous stream) using the ureteral stent device 300 is comparable to normal, healthy urine flow (e.g., the urine flow rate of an unstented, unrestricted ureter), at a flow rate between 17.5 and 18.75 ml/sec. It is noted that inability to maintain normal flow rate of urine has the potential to cause kidney damage.

[0085] It should be understood that the exemplary results and experiments discussed above relate to the proximal end being a neodymium magnet. However, as discussed above, other materials (e.g., magnets, metals, alloys, etc.) can be used for the proximal end 302. It should be understood that the material should have biocompatible and corrosion resistant properties due to its clinical use. The material should also contain magnetic properties, although a material with high magnetic flux density and magnetic remanence may interfere with the fields produced by a MRI. By way of example, cobalt-chromium is another suitable material to be used as the proximal end. Cobalt is a ferromagnetic material that has a magnetic flux density of 0.5 T. Ferromagnetic materials are materials that can be magnetized by an external magnetic field. The magnetic flux should be less than 0.5 T to be considered MRI safe, therefore another material should be added to cobalt to reduce the flux. (How Strong Are the Magnets in an MRI Machine?” HowStuffWorks Science, HowStuffWorks, 28 Jun. 2018.) Chromium is a paramagnetic materials, so it cannot be magnetized by external magnetic field. A certain alloy wt % (means weight percent) of cobalt and chromium would keep the magnetic properties of cobalt. FIG. 11 shows that under 20% chromium, the alloy would stay magnetic.

[0086] Neodymium (Nd) was selected for prototyping and proof of concept because it has magnetic properties, is inexpensive, and is easily attainable with the given size constraints and parameters. However, Neodymium has three times greater the magnetic flux density than cobalt-chromium. (“Magnet Tables & Demagnetization Curves.” SuperMagnetMan, supermagnetman.com/pages/tables-curves). To compensate for the difference, the stent retrieval device can have a higher magnetic field, which is accomplished by increasing the number of turns.

[0087] FIG. 12 shows an exemplary and non-limiting example of a drawing for a cobalt-chromium proximal end. The drawings shows length l.sub.3, and diameters d.sub.1, d.sub.3, and d.sub.4. Ranges and values for length l.sub.3 and diameters d.sub.1 and d.sub.3 have been discussed above. According to some embodiments, d.sub.4 ranges from 1.0 mm to 5.0 mm. According to some embodiments, d.sub.4 is at least 1.0 mm. According to some embodiments, d.sub.4 is at least 1.1 mm. According to some embodiments, d.sub.4 is at least 1.2 mm. According to some embodiments, d.sub.4 is at least 1.3 mm. According to some embodiments, d.sub.4 is at least 1.4 mm. According to some embodiments, d.sub.4 is at least 1.5 mm. According to some embodiments, d.sub.4 is at least 1.6 mm. According to some embodiments, d.sub.4 is at least 1.7 mm. According to some embodiments, d.sub.4 is at least 1.8 mm. According to some embodiments, d.sub.4 is at least 1.9 mm. According to some embodiments, d.sub.4 is at least 2.0 mm. According to some embodiments, d.sub.4 is at least 2.0 mm. According to some embodiments, d.sub.4 is at least 2.1 mm. According to some embodiments, d.sub.4 is at least 2.2 mm. According to some embodiments, d.sub.4 is at least 2.3 mm. According to some embodiments, d.sub.4 is at least 2.4 mm. According to some embodiments, d.sub.4 is at least 2.5 mm. According to some embodiments, d.sub.4 is at least 2.6 mm. According to some embodiments, d.sub.4 is at least 2.7 mm. According to some embodiments, d.sub.4 is at least 2.8 mm. According to some embodiments, d.sub.4 is at least 2.9 mm. According to some embodiments, d.sub.4 is at least 3.0 mm. According to some embodiments, d.sub.4 is at least 3.1 mm. According to some embodiments, d.sub.4 is at least 3.2 mm. According to some embodiments, d.sub.4 is at least 3.3 mm. According to some embodiments, d.sub.4 is at least 3.4 mm. According to some embodiments, d.sub.4 is at least 3.5 mm. According to some embodiments, d.sub.4 is at least 3.6 mm. According to some embodiments, d.sub.4 is at least 3.7 mm. According to some embodiments, d.sub.4 is at least 3.8 mm. According to some embodiments, d.sub.4 is at least 3.9 mm. According to some embodiments, d.sub.4 is at least 4.0 mm. According to some embodiments, d.sub.4 is at least 4.1 mm. According to some embodiments, d.sub.4 is at least 4.2 mm. According to some embodiments, d.sub.4 is at least 4.3 mm. According to some embodiments, d.sub.4 is at least 4.4 mm. According to some embodiments, d.sub.4 is at least 4.5 mm. According to some embodiments, d.sub.4 is at least 4.6 mm. According to some embodiments, d.sub.4 is at least 4.7 mm. According to some embodiments, d.sub.4 is at least 4.8 mm. According to some embodiments, d.sub.4 is at least 4.9 mm. According to some embodiments, d.sub.4 is at least 5.0 mm.

[0088] FIG. 13 shows an exemplary and non-limiting example of an ureteral stent device 700 of the described invention. The ureteral stent device 700 comprises a proximal end 702, a stent body 704, a distal end 706, a cap 716, and an attachment device 718. FIG. 13 further shows a kidney 708, a ureter 710, a bladder 712, and a urethra 714. The stent body 704 comprises a tubular structure comprising an inner diameter (d.sub.1) and an outer diameter (d.sub.2) (ranges and values for d.sub.1 and d.sub.2 have been discussed above), making the stent body 704 hollow. The hollow body allows urine to flow through the ureteral stent device 700. However, those skilled in the art would understand that the inner diameter can be any length necessary to allow for a healthy urine flow rate, and the outer diameter can any length to allow the ureteral stent device 700 to be placed into the ureteral 310.

[0089] The cap 716 is attached to the proximal end 702 via the attachment device 718. The attachment device 718 can be a string, a flexible polymer, or any other type of material suitable to attach the cap 716 to the proximal end 702. The attachment device 718 can be coated to reduce encrustation in the bladder. By way of example, the coating can comprise heparin, phosphorylcholine, antibiotic, carbon, hyaluronic acid, triclosan, silver, gendine, chitosan, salicylic acid, hydrogel, Teflon, titanium, or any other suitable material effective to reduce encrustation. The cap 716 comprises a porous-dome shape, wherein the shape prevents the ureteral stent device 700 from receding into the ureter 710. The shape further allows for a retrieval tool to be attached to the pores in the cap 716, and to remove the ureteral stent device 700 from the body via the urethra.

[0090] According to some embodiments, the length of the cap 716 ranges from 1.0 mm to 5.0 mm. According to some embodiments, the length of the cap 716 is at least 1.0 mm. According to some embodiments, the length of the cap 716 is at least 1.25 mm. According to some embodiments, the length of the cap 716 is at least 1.5 mm. According to some embodiments, the length of the cap 716 is at least 1.75 mm. According to some embodiments, the length of the cap 716 is at least 2.0 mm. According to some embodiments, the length of the cap 716 is at least 2.25 mm. According to some embodiments, the length of the cap 716 is at least 2.5 mm. According to some embodiments, the length of the cap 716 is at least 2.75 mm. According to some embodiments, the length of the cap 716 is at least 3.0 mm. According to some embodiments, the length of the cap 716 is at least 3.25 mm. According to some embodiments, the length of the cap 716 is at least 3.5 mm. According to some embodiments, the length of the cap 716 is at least 3.75 mm. According to some embodiments, the length of the cap 716 is at least 4.0 mm. According to some embodiments, the length of the cap 716 is at least 4.25 mm. According to some embodiments, the length of the cap 716 is at least 4.75 mm. According to some embodiments, the length of the cap 716 is at least 5.0 mm. According to some embodiments, the length of the cap 716 is at least 5.25 mm. According to some embodiments, the length of the cap 716 is at least 5.5 mm. According to some embodiments, the length of the cap 716 is at least 5.75 mm. According to some embodiments, the length of the cap 716 is at least 6.0 mm. According to some embodiments, the length of the cap 716 is at least 6.25 mm. According to some embodiments, the length of the cap 716 is at least 6.5 mm. According to some embodiments, the length of the cap 716 is at least 6.75 mm. According to some embodiments, the length of the cap 716 is at least 7.0 mm. According to some embodiments, the length of the cap 716 is at least 7.25 mm. According to some embodiments, the length of the cap 716 is at least 7.5 mm. According to some embodiments, the length of the cap 716 is at least 7.75 mm. According to some embodiments, the length of the cap 716 is at least 8.0 mm. According to some embodiments, the length of the cap 716 is at least 8.25 mm. According to some embodiments, the length of the cap 716 is at least 8.5 mm. According to some embodiments, the length of the cap 716 is at least 8.75 mm. According to some embodiments, the length of the cap 716 is at least 9.0 mm. According to some embodiments, the length of the cap 716 is at least 9.25 mm. According to some embodiments, the length of the cap 716 is at least 9.5 mm. According to some embodiments, the length of the cap 716 is at least 9.75 mm. According to some embodiments, the length of the cap 716 is at least 10.0 mm. According to some embodiment, the length of the cap 716 is greater than 10.0 mm

[0091] FIGS. 14A and 14B show a closer view of the cap 716 and the attachment device 718. The bladder boundary 720 is a representative line for illustration purposes of the location of the bladder entrance in relation to the attachment device 718. Those skilled in the art would understand that the location of the attachment device 718 in FIG. 14A is by way of example.

[0092] Returning to FIG. 13, the distal end 706 can comprise a tip and can form any one of a J-curl, a j-shape, a pigtail loop, or any other type of curl capable of securing the distal end 706 in the kidney 708. The tip can be tapered. The kidney 708 is used to show a general relation between the kidney entrance and the distal end 706, and is used for illustrative purposes only. Similarity, the bladder 712 is used to show a general relation between the bladder 712 and the proximal end 702, the cap 716, and the attachment device 718, and is used for illustrative purposes only.

[0093] In this embodiment, the proximal end 702 does not enter the bladder 712, and terminates in the ureter 710, the cap 716 is positioned inside the bladder 712, and the attachment device 718 is positioned partly in the ureter 710 and partly in the bladder 712. This is solely by way of example. In other embodiments, the proximal end 702 can terminal in the bladder 712, or anywhere else along the ureter 710.

[0094] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although any methods and materials similar or equivalent to those described herein can also be used in the practice or testing of the present invention, exemplary methods and materials have been described. All publications mentioned herein are incorporated herein by reference to disclose and described the methods and/or materials in connection with which the publications are cited.

[0095] It must be noted that as used herein and in the appended claims, the singular forms “a”, “an”, and “the” include plural references unless the context clearly dictates otherwise.

[0096] The publications discussed herein are provided solely for their disclosure prior to the filing date of the present application and each is incorporated by reference in its entirety. Nothing herein is to be construed as an admission that the present invention is not entitled to antedate such publication by virtue of prior invention. Further, the dates of publication provided may be different from the actual publication dates which may need to be independently confirmed.

[0097] While the present invention has been described with reference to the specific embodiments thereof it should be understood by those skilled in the art that various changes may be made and equivalents may be substituted without departing from the true spirit and scope of the invention. In addition, many modifications may be made to adopt a particular situation, material, composition of matter, process, process step or steps, to the objective spirit and scope of the present invention. All such modifications are intended to be within the scope of the claims appended hereto.