title: Diuresis renography for differentiation of upper urinary tract dilatation from obstruction: F+20 and F-15 methods.
abstract: BACKGROUND
  The aim of this study was to evaluate diuresis renography with an intravenous injection of furosemide 20 minutes after administering the radiopharmaceutical (F+20 protocol) or 15 minutes before (F-15 protocol) in patients with upper urinary tract dilatation.
  
  
  METHODS
  Twenty-one patients with pyelocaliceal system dilatation, but not ureteral dilatation, on ultrasonography were evaluated. The patients underwent diuresis renography using the F+20 and F-15 protocols. Renal scan findings and kidney split function were recorded. Then, the patients underwent surgical or conservative treatment according to their clinical conditions and imaging results. Follow-up was done 3 and 6 months postoperatively by physical examination, intravenous urography, and diuresis renography.
  
  
  RESULTS
  Eleven patients (52.4%) had complete obstruction in both protocols of renography, and 5 (23.8%) had an equivocal result in the F+20 and an obstructive pattern in the F-15. These patients underwent surgical operation. In 3 patients (14.3%), both protocols demonstrated a normal urinary tract. In 2 patients (9.5%), a nonobstructive response in the F+20 and an equivocal result in the F-15 were seen. One of them underwent surgical operation because of impaired kidney function during the follow-up and 1 was treated conservatively. Overall, obstruction was found in 16 out of 21 patients (76.2%) by the F-15 protocol, while it was found in 11 (52.4%) by the F+20 protocol (P=.01). The mean kidney split function was 55.15% +/- 7.82% and 54.81% +/- 6.87% in F+20 and F-15 protocols, respectively (P=.45).
  
  
  CONCLUSIONS
  Using the F-15 protocol may reduce the equivocal results of the F+20 for diuresis renography.
authors.affiliation: Department of Urology, Imam Reza Hospital, Mashhad University of Medical Sciences, Mashhad, Iran. r-taghavi@mums.ac.ir
authors.forename: Rahim
authors.initials: R
authors.lastname: Taghavi
authors.forename: Kamran
authors.initials: K
authors.lastname: Ariana
authors.forename: Davoud
authors.initials: D
authors.lastname: Arab
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D003545:Cysteine / Q000031:analogs & derivatives; D004108:Dilatation, Pathologic / Q000000981:diagnostic imaging; D004232:Diuretics / Q000008:administration & dosage*; D004334:Drug Administration Schedule; D005260:Female; D005665:Furosemide / Q000008:administration & dosage*; D006801:Humans; D007275:Injections, Intravenous; D008297:Male; D015609:Organotechnetium Compounds; D011866:Radioisotope Renography / Q000379:methods*; D019275:Radiopharmaceuticals; D014551:Urinary Tract / Q000000981:diagnostic imaging*; D014570:Urologic Diseases / Q000000981:diagnostic imaging*
chemical_list: D004232:Diuretics; D015609:Organotechnetium Compounds; D019275:Radiopharmaceuticals; C073806:technetium Tc 99m-ethylenedicysteine; D005665:Furosemide; D003545:Cysteine