title: Dual-Energy X-Ray Absorptiometry for Measurement of Phalangeal Bone Mineral Density on a Slot-Scanning Digital Radiography System.
abstract: OBJECTIVE
  In this paper, we assess the feasibility of using two detectors in a slot-scanning digital radiography system to acquire images for measuring bone mineral density (BMD) of the middle phalanx of the middle finger using dual-energy X-ray absorptiometry (DXA).
  
  
  METHODS
  Simulations were used to evaluate the spectral separation of the low- and high-energy spectra and detective quantum efficiency was used for assessing image quality. Scan parameters were chosen to optimize spectral separation, image quality, and radiation dose. We introduce the measurement of volumetric BMD (vBMD) using basis material decomposition. We assess the accuracy of our methods by comparing measurements taken using bone images against reference data derived from subsequent incineration of the bones. In vivo scans were conducted to evaluate the system precision (repeatability) and agreement with a clinical densitometer.
  
  
  RESULTS
  Average errors for bone mineral content (BMC), areal BMD (aBMD), and vBMD were 4.85%, 5.49%, and 12.77%, respectively. Our system had good agreement with a clinical densitometer based on concordance correlation coefficient values of 0.92 and 0.98 for aBMD and BMC, respectively. Precision studies yielded coefficient of variation (CV) values of 1.35% for aBMD, 1.48% for BMC, and 1.80% for vBMD. The CV values of all measurements were within 2%, indicating that the methods have clinically acceptable precision.
  
  
  CONCLUSIONS
  We conclude that our techniques yield bone measurements with high accuracy, clinically acceptable precision, and good agreement with a clinical densitometer.
  
  
  CONCLUSIONS
  We have shown the clinical potential of phalangeal DXA measurements of aBMD and vBMD on a slot-scanning digital radiography system.
authors.forename: Ronald
authors.initials: R
authors.lastname: Dendere
authors.forename: J Herman
authors.initials: JH
authors.lastname: Potgieter
authors.forename: Stefan
authors.initials: S
authors.lastname: Steiner
authors.forename: Sarah P
authors.initials: SP
authors.lastname: Whiley
authors.forename: Tania S
authors.initials: TS
authors.lastname: Douglas
mesh_terms: D015502:Absorptiometry, Photon / Q000379:methods*; D000465:Algorithms; D015519:Bone Density; D005260:Female; D050278:Finger Phalanges / Q000000981:diagnostic imaging*; D006801:Humans; D008297:Male; D019047:Phantoms, Imaging; D011856:Radiographic Image Enhancement / Q000379:methods*