title: Opportunistic screening for osteoporosis on routine computed tomography? An external validation study.
abstract: OBJECTIVE
  Opportunistic screening for osteoporosis using computed tomography (CT) examinations that happen to visualise the spine can be used to identify patients with osteoporosis. We sought to verify the diagnostic performance of vertebral Hounsfield unit (HU) measurements on routine CT examinations for diagnosing osteoporosis in a separate, external population.
  
  
  METHODS
  Consecutive patients who underwent a CT examination of the chest or abdomen and had also received a dual-energy X-ray absorptiometry (DXA) test were retrospectively included. CTs were evaluated for vertebral fractures and vertebral attenuation (density) values were measured. Diagnostic performance measures and the area under the receiver operator characteristics curve (AUC) for diagnosing osteoporosis were calculated.
  
  
  RESULTS
  Three hundred and two patients with a mean age of 57.9 years were included, of which 82 (27%) had osteoporosis according to DXA and 65 (22%) had vertebral fractures. The diagnostic performance for vertebral HU measurements was modest, with a maximal AUC of 0.74 (0.68 - 0.80). At that optimal threshold the sensitivity was 62% (51 - 72%) and the specificity was 79% (74 - 84%).
  
  
  CONCLUSIONS
  We confirmed that simple trabecular vertebral density measurements on routine CT contain diagnostic information related to bone mineral density as measured by DXA, albeit with substantially lower diagnostic accuracy than previously reported.
  
  
  CONCLUSIONS
  • We externally validated the value of vertebral trabecular bone attenuation for osteoporosis • These diagnostic performance measures were, however, substantially lower than previously reported • This information might be useful when considering the implementation of opportunistic osteoporosis screening.
authors.affiliation: Department of Radiology, University Medical Center Utrecht, Utrecht, The Netherlands, cfmbuckens@gmail.com.
authors.forename: Constantinus F
authors.initials: CF
authors.lastname: Buckens
authors.forename: Gawein
authors.initials: G
authors.lastname: Dijkhuis
authors.forename: Bart
authors.initials: B
authors.lastname: de Keizer
authors.forename: Harald J
authors.initials: HJ
authors.lastname: Verhaar
authors.forename: Pim A
authors.initials: PA
authors.lastname: de Jong
mesh_terms: D015502:Absorptiometry, Photon / Q000379:methods; D000368:Aged; D015519:Bone Density / Q000502:physiology; D042241:Early Diagnosis; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging / Q000379:methods; D010024:Osteoporosis / Q000000981:diagnostic imaging* / Q000503:physiopathology; D058866:Osteoporotic Fractures / Q000000981:diagnostic imaging* / Q000503:physiopathology; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D016103:Spinal Fractures / Q000000981:diagnostic imaging* / Q000503:physiopathology; D014057:Tomography, X-Ray Computed / Q000379:methods