title: Artificial hydroureteronephrosis to facilitate MR urography during pregnancy.
abstract: BACKGROUND
  Insertion of a percutaneous nephrostomy (PCN) catheter decompresses the upper urinary tract, thereby removing the hydroureteronephrosis upon which magnetic resonance (MR) urography is dependent for diagnosing the precise level and cause of ureteric obstruction.
  
  
  METHODS
  We present the case of a young woman who required PCN insertion during pregnancy.
  
  
  RESULTS
  Only when unenhanced T2-weighted MR urography was repeated after the creation of an artificial hydronephrosis by an injection of sterile saline via the PCN catheter was the diagnosis of stone in the mid-ureter later made possible.
  
  
  CONCLUSIONS
  This case highlights an easy solution to a limitation with the use of MR urography during pregnancy, when a physiological hydroureteronephrosis has been relieved by the insertion of a PCN catheter.
authors.affiliation: Department of Urology, St Vincent's University Hospital, University College Dublin, Dublin 4, Ireland. steconnolly@rcsi.ie
authors.forename: S S
authors.initials: SS
authors.lastname: Connolly
authors.forename: L P
authors.initials: LP
authors.lastname: Browne
authors.forename: C D
authors.initials: CD
authors.lastname: Collins
authors.forename: G M
authors.initials: GM
authors.lastname: Lennon
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D006869:Hydronephrosis / Q000175:diagnosis* / Q000503:physiopathology; D008279:Magnetic Resonance Imaging; D009403:Nephrostomy, Percutaneous / Q000295:instrumentation / Q000379:methods*; D011247:Pregnancy