title: The layered pyelogram in hydronephrosis.
abstract: Fifty patients were studied with erect films at excretory urography. Twenty-eight had hydronephrosis, bilateral in two cases; a total of 30 hydronephrotic kidneys were therefore investigated. Thin layers of contrast medium were shown in the dilated calyces in 29 of the 30 kidneys. The layered pyelogram is a simple, sensitive urographic sign of hydronephrosis, which may be demonstrated in the absence of a discernible pyelogram in the routine film or tomograph. The basis of layering has been investigated by simple experiments. Since the layered pyelogram may be the only urographic evidence of a poorly excreting hydronephrotic kidney, erect films should be routinely used at excretory urography when this condition is to be diagnosed or excluded.
mesh_terms: D000293:Adolescent; D000328:Adult; D003973:Diatrizoate; D006801:Humans; D006869:Hydronephrosis / Q000000981:diagnostic imaging* / Q000209:etiology; D007668:Kidney / Q000000981:diagnostic imaging; D007670:Kidney Calices / Q000000981:diagnostic imaging; D008297:Male; D008875:Middle Aged; D011187:Posture; D014567:Urography / Q000379:methods*
chemical_list: D003973:Diatrizoate