UrographyUrologic DiseasesUreteral CalculiUreteral DiseasesIodopyracetMultidetector Computed TomographyHematuriaUreterUrinary TractHydronephrosisUrinary CalculiTomography, X-Ray ComputedUreteral ObstructionCystoscopyKidney CalicesDiatrizoate MeglumineUrolithiasisFlank PainColicContrast MediaIodamideIohexolRadiography, AbdominalUltrasonographyUrinary Bladder DiseasesUreteral NeoplasmsKidney PelvisDiatrizoateVesico-Ureteral RefluxTomography, Spiral ComputedSensitivity and SpecificityDilatation, PathologicUrologic NeoplasmsPhysical ExaminationUrologic Surgical ProceduresUrinary Tract InfectionsRadiographic Image Interpretation, Computer-AssistedKidney DiseasesKidneyProspective Studies