title: Absolute measurements of total-body calcium using prompt gamma neutron analysis and internal chlorine standardization: results in renal patients.
abstract: Measurement of total-body calcium (TBCa) is important in the study of several medical conditions. Neutron activation analysis (NAA) is sufficiently precise for serial measurements, but in order to provide single, absolute determinations of TBCa, it requires a correction for body habitus. A method is described for the absolute determination of TBCa by comparing the total-body chlorine, obtained by NAA, with that obtained by stable bromine dilution. The method is applied to a group of thirty patients who had been treated for chronic renal failure, and significant differences are found between measured values of TBCa and those predicted for 'normal' healthy subjects. The overall experimental error in the absolute determination of TBCa is estimated to be 8%, for a dose equivalent of 3.1 mSv (based on skin dose, and a quality factor of 10 for neutrons).
authors.affiliation: Department of Physics, University College of Swansea, Singleton Park, UK.
authors.forename: C J
authors.initials: CJ
authors.lastname: Evans
authors.forename: D W
authors.initials: DW
authors.lastname: Thomas
authors.forename: S J
authors.initials: SJ
authors.lastname: Ryde
authors.forename: A J
authors.initials: AJ
authors.lastname: Williams
mesh_terms: D001823:Body Composition; D002118:Calcium / Q000032:analysis*; D002713:Chlorine / Q000592:standards*; D005260:Female; D006801:Humans; D007676:Kidney Failure, Chronic / Q000503:physiopathology*; D008297:Male; D009501:Neutron Activation Analysis
chemical_list: D002713:Chlorine; D002118:Calcium