title: Optimization of data analysis for the in vivo neutron activation analysis of aluminum in bone.
abstract: An existing system at McMaster University has been used for the in vivo measurement of aluminum in human bone. Precise and detailed analysis approaches are necessary to determine the aluminum concentration because of the low levels of aluminum found in the bone and the challenges associated with its detection. Phantoms resembling the composition of the human hand with varying concentrations of aluminum were made for testing the system prior to the application to human studies. A spectral decomposition model and a photopeak fitting model involving the inverse-variance weighted mean and a time-dependent analysis were explored to analyze the results and determine the model with the best performance and lowest minimum detection limit. The results showed that the spectral decomposition and the photopeak fitting model with the inverse-variance weighted mean both provided better results compared to the other methods tested. The spectral decomposition method resulted in a marginally lower detection limit (5μg Al/g Ca) compared to the inverse-variance weighted mean (5.2μg Al/g Ca), rendering both equally applicable to human measurements.
authors.affiliation: Medical Physics & Applied Radiation Sciences, McMaster University, Hamilton, Canada. Electronic address: katalmh@mcmaster.ca.
authors.forename: H K
authors.initials: HK
authors.lastname: Mohseni
authors.affiliation: University of Florida Proton Therapy Institute, Jacksonville, FL, USA.
authors.forename: W
authors.initials: W
authors.lastname: Matysiak
authors.affiliation: Medical Physics & Applied Radiation Sciences, McMaster University, Hamilton, Canada.
authors.forename: D R
authors.initials: DR
authors.lastname: Chettle
authors.affiliation: Medical Physics & Applied Radiation Sciences, McMaster University, Hamilton, Canada.
authors.forename: S H
authors.initials: SH
authors.lastname: Byun
authors.affiliation: Canadian Nuclear Laboratories, Chalk River Laboratories, Ontario, Canada.
authors.forename: N
authors.initials: N
authors.lastname: Priest
authors.affiliation: Ontario Power Generation, Whitby, Ontario, Canada.
authors.forename: J
authors.initials: J
authors.lastname: Atanackovic
authors.affiliation: Medical Physics & Applied Radiation Sciences, McMaster University, Hamilton, Canada.
authors.forename: W V
authors.initials: WV
authors.lastname: Prestwich
mesh_terms: D000465:Algorithms; D000535:Aluminum / Q000032:analysis*; D040761:Biomimetic Materials / Q000737:chemistry; D003627:Data Interpretation, Statistical; D050276:Hand Bones / Q000737:chemistry*; D006801:Humans; D009501:Neutron Activation Analysis / Q000379:methods*; D009716:Numerical Analysis, Computer-Assisted; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D000535:Aluminum
keywords: Aluminum; Bone; Data analysis; Gamma spectroscopy; In vivo neutron activation; Photopeak fit analysis; Spectral decomposition