Risk of injury to adjacent organs with lower-pole fluoroscopically guided percutaneous nephrostomy: Evaluation with prone, supine, and multiplanar reformatted CT

PURPOSE: To assess the risk of injury to organs near the kidney during lower-pole fluoroscopically guided percutaneous nephrostomy by evaluation of prone, supine, and multiplanar reformatted computed tomography (CT). MATERIALS AND METHODS: Eighty-three patients who underwent prone and supine CT examinations were identified retrospectively. The expected path of nephrostomy tube placement to the lower-pole calyx was simulated on prone and supine axial images and multiplanar CT reformations. Intervening organs along this path were considered at risk for injury and were recorded for each kidney (N = 166). RESULTS: The risk of organ injury as determined on multiplanar reformatted prone images (n = 5) and supine images (n = 0) was significantly less (P < .05) than determined on axial prone images (n = 25) or supine images (n = 10). The colon was the only organ identified to be at risk for injury during the simulated lower-pole percutaneous nephrostomy placement; spleen and liver were not seen along the nephrostomy path on axial or multiplanar reformatted images. CONCLUSION: Lower-pole fluoroscopically guided percutaneous nephrostomy carries a low risk of visceral injury, and the risk of injury is overestimated by evaluation of axial CT images alone compared with oblique parasagittal reformations.