title: The calyceal crescent--a roentgenographic sign of obstructive hydronephrosis.
mesh_terms: D002648:Child; D002675:Child, Preschool; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D006869:Hydronephrosis / Q000000981:diagnostic imaging* / Q000209:etiology; D007223:Infant; D007680:Kidney Neoplasms / Q000000981:diagnostic imaging; D007682:Kidney Pelvis / Q000000981:diagnostic imaging*; D007684:Kidney Tubules / Q000000981:diagnostic imaging* / Q000473:pathology; D008297:Male; D007690:Polycystic Kidney Diseases / Q000000981:diagnostic imaging; D011379:Prognosis; D014567:Urography; D009396:Wilms Tumor / Q000000981:diagnostic imaging