Percutaneous nephrostomy or nephroureteral stent placement: Placement of a catheter through the skin, directly into the kidney to drain from the collecting system. This is typically done to treat a downstream obstruction of urine.
Ureteral stent exchange: indwelling double-J type ureteral stents, typically placed by urologist using cystoscopy, may be exchanged in retrograde fashion through the female urethra. The IR uses a thin wire snare under fluoroscopy to capture the distal portion of the stent. After partially extracting the distalmost stent, exchange for a new stent can be accomplished over a guidewire.
