Wire-Based Ureteral Stents: Impact on Tensile Strength and Compression

Choosing an Appropriate Length of Loop Type Ureteral Stent Using Direct Ureteral Length Measurement

“…A stent that is too long for the ureteral length may cause symptoms of urinary irritation, and stents that are too short may migrate to the ureter [6,7,17,18] . Various forms, caliber, and materials are used to avoid urinary irritation [8,9,[19][20][21] . However, placing a ureteral stent in an appropriate position and selecting an appropriate length of the ureteral stent are the most important factors to avoid such irritation [12] .…”

Resistance to Extrinsic Compression and Maintenance of Intraluminal Flow in Coil-Reinforced Stents (Silhouette® Scaffold Device): An In Vitro Study

“…Alternatives to overcome this problem have been attempted and include placement of tandem Double-J stents, 14 metal mesh stents, 15 and, more recently, coil-reinforced ureteral stents. 9 Parallel tandem Double-J stents are believed to allow for urine drainage between the two stents and to offer more resistance to kinking without worsening irritative symptoms compared with a single Double-J. However, ureteral narrowing may not allow for placement of two stents simultaneously.…”

“…4 Hardness of material was reported to be a more important feature than luminal diameter in the maintenance of flow through the stent. 9,13,16 The coil-reinforced Applied Silhouette 4.6 F stent has been previously shown to offer a resistance to outside compression at least twice that of previously tested non-coil-reinforced stents while maintaining flexibility of the durometer similar to other stents. 9 Our study demonstrates that the current 8 F Applied Silhouette Scaffold Device maintains its intraluminal flow under increasing compression cycles, being able to resist higher compression forces compared with the 4.6 F version (28,856 AE 2592 kPa vs. 105 AE 11 kPa, respectively).…”

“…8 As such, intraluminal patency is the corner stone to assure successful urinary drainage and may ultimately be most dependent on the stent cross-sectional stability. 9 Resistance to extrinsic compression forces has previously been reported on several different commercially available Double-J stents, but little has been reported on the effects of increasing obstruction on intraluminal flow. [10][11][12] We performed an in vitro study to evaluate the ability of a coil-reinforced ureteral stent (Silhouette Ò Scaffold Device; Applied Medical, Rancho San Mirage, CA) to maintain intraluminal flow under increasing extrinsic mechanical compression.…”

Endourologic Management of Malignant Ureteral Obstruction: Indications, Results, and Quality-of-Life Issues

“…Both coiled stents were less stiff than the C-Flex stent, while the Resonance stent demonstrated the higher tensile strength and the Silhouette was found to be the most resistant to extrinsic compression. 119 Clinical experience with the new metal stents. Insertion of the Resonance stent is slightly different from the technique used for insertion of conventional ureteral stents and can be performed antegrade or retrograde.…”