Percutaneous nephrostomy is an interventional radiology/surgical procedure in which the renal pelvis is punctured whilst using imaging as guidance. Images are obtained once an antegrade pyelogram (an injection of contrast), with a fine needle, has been performed. This contrast is used to show calcifications at the renal pelvis. A nephrostomy tube may then be placed to allow drainage.
See also 
- ^ Longmore, Murray; Ian Wilkinson, Tom Turmezei, Chee Kay Cheung (2007). Oxford Handbook of Clinicial Medicine, 7th edition. Oxford University Press. p. 731. ISBN 0-19-856837-1.