| [[File:Antegrade pyelogram of grade III hydronephrosis with obstruction at the ureterovesical junction.jpg|thumb|left|<ref>{{cite journal|last1=Efe|first1=Erkan|last2=Bakacak|first2=Murat|last3=Serin|first3=Salih|last4=Kolus|first4=Eyüp|last5=Ercan|first5=Önder|last6=Resim|first6=Sefa|title=Hormonal Treatment for Severe Hydronephrosis Caused by Bladder Endometriosis|journal=Case Reports in Urology|volume=2014|year=2014|pages=1–5|issn=2090-696X|doi=10.1155/2014/891295}}</ref>]]
The tip of the nephrostomy is located in an inferior calyx.<br>Approximately 50 ml of contrast is infused, whereupon the patient feels flank pain. There is grade III hydronephrosis and hydroureter, with tapering at the ureterovesical junction, and no contrast in the bladder. No leakage.