Retro-renal colon: role in percutaneous access

Introduction Upper urinary tract is accessed for various procedures. The maximum numbers of procedures are carried out in prone position. Perforation of the colon is a well-known complication. The incidence of retrorenal colon varies from 10–20 % in prone position, but the chances of injury is around <1 %. These facts lead us to review the occurrence of retrorenal colon. The CT scan is imaging test of choice.