Delayed excretory phase CT image of contrast extravasation into a urinoma (white arrow) following left ureteric injury during a left partial nephrectomy. The yellow arrow demonstrates the site of active contrast extravasation from the left pelvi-ureteric junction, which was injured during the operation. A nephrostomy catheter (red arrow) was sited to decompress the collecting system and to facilitate urinary drainage. The patient developed persistent pelvi-ureteric junction obstruction and required a completion left nephrectomy