Korean J Urol.  2015 May;56(5):405-408. 10.4111/kju.2015.56.5.405.

Knotted stents: Case report and outcome analysis

• Kim MS
• Lee HN
• Hwang H

• KMID: 2155322
• DOI: http://doi.org/10.4111/kju.2015.56.5.405

Abstract

A knotted ureteral stent is an extremely rare condition, with fewer than 20 cases reported in the literature; however, it is difficult to treat. We report a case in which a folded Terumo guidewire was successfully used to remove a knotted stent percutaneously without anesthesia. We also review the current literature on predisposing factors and management strategies for knotted ureteral stents.

Keyword

Stents; Ureter; Urolithiasis

MeSH Terms

Anti-Bacterial Agents/therapeutic use
Humans
Kidney Calculi/*radiography/*therapy
Lithotripsy
Male
Middle Aged
Stents/*adverse effects
Ureter
Anti-Bacterial Agents

Figure

• 

  Fig. 1 Coronal scans obtained via nonenhanced computed tomography. A 0.4-cm upperureteral stone with no hydronephrosis (A: blue arrow) and a 2.0-cm renal stone in lower calyx (B: blue arrow) were identified.

• 

  Fig. 2 X-ray images of the kidney, ureter, and bladder. (A) Pretreatment (upper arrow: renal stone, lower arrow: upper ureteral stone). (B) Immediately after insertion of a double-J stent. (C) Steinstrasse after extracorporeal shock wave lithotripsy (blue arrow: steinstrasse). (D) Knot formation (blue arrow: knott).

• 

  Fig. 3 Fluoroscopic images of antegrade ureteral stent removal. A 7-French angio sheath was inserted under ultrasonographic and fluoroscopic guidance, and the KMP (Beacon Tip Torcon NB advantage angiographic catheter, Cook Medical, Bloomington, IN, USA) catheter was inserted through the sheath. (A) A folded 0.018 Terumo guidewire was inserted in the area of the knot formation through the KMP catheter. (B) The knotted stent was caught in the folded guidewire and was removed percutaneously. After the procedure, an 8.5-French pigtail catheter was inserted in the kidney.

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