title: Dose absorption in lumbar and femoral dual energy X-ray absorptiometry examinations using three different scan modalities: an anthropomorphic phantom study.
abstract: The aim of this study was to measure the effective dose on an anthropomorphic phantom undergoing lumbar and femoral dual energy X-ray absorption (DXA) examinations, using 3 different scan modalities (fast-array [FA], array [A], high-definition [HD]), and assess the differences in the lifetime attributable risk (LAR) of cancer due to radiation. An anthropomorphic phantom was used. Thermoluminescent dosimeters were placed over 12 anatomic phantom regions and outside the room (to measure background radiation). Fifty scans on the femur and spine were performed for each mode. The dose relative to a single DXA scan for each dosimeter was measured (mean over the 50 scans) and the background radiation was then subtracted. The equivalent dose per organ was obtained. The total body effective dose was calculated by adding the equivalent doses. We estimated the lifetime dose absorption and LAR for cancer for a male and a female patient undergoing 36 DXA studies (18 lumbar, 18 femoral) every 21 months for 32 years. The effective dose for lumbar scans was FA = 17.79 μSv, A = 32.88 μSv, HD = 31.08 μSv; for femoral scans, FA = 5.29 μSv, A = 9.55 μSv, HD = 7.54 μSv. LAR estimation showed a minimal increase in cancer risk (range 4.55 × 10⁻⁴% [FA, femoral, male] to 4.02 × 10⁻³% [A, lumbar, female]). The lifetime dose absorption and LAR for cancer for a male and a female patient undergoing 36 DXA studies (18 lumbar, 18 femoral) every 21 months for 32 years were 0.756 mSv, 3.82 × 10(-3)% and 0.756 mSv, 5.11 × 10⁻³%, respectively. DXA examinations cause radiation levels that are comparable to the background radiation. Regardless of the scan modality or the anatomic site, a patient undergoing DXA scans for a lifetime has a negligible increased risk of developing cancer.
authors.affiliation: Scuola di Specializzazione in Radiodiagnostica, Università degli Studi di Milano, Milano, Italy. Electronic address: michele.bandirali@hotmail.it.
authors.forename: Michele
authors.initials: M
authors.lastname: Bandirali
authors.affiliation: Scuola di Specializzazione in Radiodiagnostica, Università degli Studi di Milano, Milano, Italy.
authors.forename: Ezio
authors.initials: E
authors.lastname: Lanza
authors.affiliation: Scuola di Specializzazione in Radiodiagnostica, Università degli Studi di Milano, Milano, Italy.
authors.forename: Carmelo
authors.initials: C
authors.lastname: Messina
authors.affiliation: Dipartimento di Scienze Biomediche per la Salute, Università degli Studi di Milano, Milano, Italy; Servizio di Radiologia, IRCCS Policlinico San Donato, San Donato Milanese, Italy.
authors.forename: Luca Maria
authors.initials: LM
authors.lastname: Sconfienza
authors.affiliation: Servizio di Fisica Sanitaria, Fondazione IRCCS Ca' Granda - Ospedale Maggiore Policlinico, Milano, Italy.
authors.forename: Roberto
authors.initials: R
authors.lastname: Brambilla
authors.affiliation: Servizio di Fisica Sanitaria, Fondazione IRCCS Ca' Granda - Ospedale Maggiore Policlinico, Milano, Italy.
authors.forename: Rozza
authors.initials: R
authors.lastname: Maurizio
authors.affiliation: Mineralometria Ossea Computerizzata e Ambulatorio Malattie Metabolismo Minerale e Osseo, Servizio di Medicina Nucleare, Fondazione IRCCS Ca' Granda - Ospedale Maggiore Policlinico, Milano, Italy.
authors.forename: Daniele
authors.initials: D
authors.lastname: Marchelli
authors.affiliation: Mineralometria Ossea Computerizzata e Ambulatorio Malattie Metabolismo Minerale e Osseo, Servizio di Medicina Nucleare, Fondazione IRCCS Ca' Granda - Ospedale Maggiore Policlinico, Milano, Italy.
authors.forename: Luca Petruccio
authors.initials: LP
authors.lastname: Piodi
authors.affiliation: Servizio di Radiologia, IRCCS Policlinico San Donato, San Donato Milanese, Italy.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Di Leo
authors.affiliation: Mineralometria Ossea Computerizzata e Ambulatorio Malattie Metabolismo Minerale e Osseo, Servizio di Medicina Nucleare, Fondazione IRCCS Ca' Granda - Ospedale Maggiore Policlinico, Milano, Italy.
authors.forename: Fabio Massimo
authors.initials: FM
authors.lastname: Ulivieri
authors.affiliation: Dipartimento di Scienze Biomediche per la Salute, Università degli Studi di Milano, Milano, Italy; Servizio di Radiologia, IRCCS Policlinico San Donato, San Donato Milanese, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Sardanelli
mesh_terms: D015502:Absorptiometry, Photon / Q000295:instrumentation*; D000042:Absorption; D015519:Bone Density; D004307:Dose-Response Relationship, Radiation; D005260:Female; D005269:Femur / Q000000981:diagnostic imaging* / Q000528:radiation effects; D006801:Humans; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging* / Q000528:radiation effects; D008297:Male; D010024:Osteoporosis / Q000000981:diagnostic imaging / Q000378:metabolism; D019047:Phantoms, Imaging; D013819:Thermoluminescent Dosimetry / Q000379:methods
keywords: Anthropomorphic phantom; dual energy X-ray absorptiometry; radiation exposure