Computed tomographic evaluation and guided correction of malpositioned nephrostomy catheters

Background: To determine the utility of computed tomography (CT) in the det ection and correction of malpositioned nephrostomy catheters after contrast spillage during nephrostograms. Methods: CT was performed in nine patients after an abnormal (contrast spil lage) tube nephrostogram performed during or after nephrostomy tube placeme nt. CT was used to locate the nephrostomy catheter position in relation to the renal collecting system. If possible, CT was also used for guidance and repositioning of the nephrostomy catheters into the intrarenal collecting system. Results: In all nine cases, CT was successful in detecting the position of the suspected malpositioned catheter. In seven of nine cases, CT demonstrat ed the catheter outside the renal collecting system and effectively helped reposition the catheters into the intrarenal collecting system. In one case , the malpositioned nephrostomy catheter was within the intraperitoneal cav ity and required surgical correction. Another case required fluoroscopic-gu ided repositioning for the initial nephrostomy catheter, which was partly p osterior to the kidney and partly within the kidney. The catheter in this l atter case was successfully advanced over a guidewire into the collecting s ystem. Conclusions: CT may be used to detect possible catheter malposition associa ted with nephrostomy tube placement. CT may also be used to successfully gu ide catheter repositioning in the renal collecting system.