Traditional plastic BARD double j ureteral stent Cystoscopic image of COOK Resonance metallic stent in urinary bladder exiting ureteral orifice

Obstruction of the kidneys and upper urinary tract can lead to hydronephrosis (swelling of the kidney).

Benign processes such as scarring and fibrosis can lead to obstruction. Certain malignancies can compress the ureters extrinsically (from the outside) or directly invade the wall of the ureter resulting in back-pressure to the kidney.

Relief of the obstruction (decompression) by placing a ureteral stent is an important tool in the armamentarium used by urologists. Most stents are made of polymers or silicone. A newer metallic stent (Cook Medical) offers more reliable drainage by withstanding up to 25x's more extrinsic compression than plastic stents.

Stent positioned in the kidney