title: Case report: inverted contrast medium--urine level in the bladder on computed tomography.
abstract: Fluid-fluid levels within structures are caused by differences between the specific gravity of the fluids. This results in a characteristic appearance on computed tomography (CT), with urine which contains contrast medium and has a high specific gravity layering posteriorly in the dependent portion of the bladder, while lower specific gravity, non-opacified urine is found uppermost. We report a patient in whom the contrast medium-urine level was inverted because of sediment in the dependent part of the bladder.
authors.affiliation: Department of Diagnostic Radiology, Christie Hospital and Holt Radium Institute, Manchester.
authors.forename: B M
authors.initials: BM
authors.lastname: Carrington
authors.forename: R J
authors.initials: RJ
authors.lastname: Johnson
mesh_terms: D000328:Adult; D003287:Contrast Media; D005260:Female; D006801:Humans; D014057:Tomography, X-Ray Computed; D001743:Urinary Bladder / Q000000981:diagnostic imaging*; D014556:Urine
chemical_list: D003287:Contrast Media