Skip to main content

13.02.2019 | Computed Tomography | Ausgabe 9/2019

European Radiology 9/2019

DXA-equivalent quantification of bone mineral density using dual-layer spectral CT scout scans

European Radiology > Ausgabe 9/2019
Alexis Laugerette, Benedikt J. Schwaiger, Kevin Brown, Lena C. Frerking, Felix K. Kopp, Kai Mei, Thorsten Sellerer, Jan Kirschke, Thomas Baum, Alexandra S. Gersing, Daniela Pfeiffer, Alexander A. Fingerle, Ernst J. Rummeny, Roland Proksa, Peter B. Noël, Franz Pfeiffer
Wichtige Hinweise

Electronic supplementary material

The online version of this article (https://​doi.​org/​10.​1007/​s00330-019-6005-6) contains supplementary material, which is available to authorized users.

Summary statement

The presented method, based on spectral CT scout scans, allows to reliably determine areal BMD in state-of-the-art phantom and in sample patient data. The results suggest that the performance of the method is possibly similar to that of DXA for the phantom experiments performed in this work.

Publisher’s wote

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.



To develop and evaluate a method for areal bone mineral density (aBMD) measurement based on dual-layer spectral CT scout scans.


A post-processing algorithm using a pair of 2D virtual mono-energetic scout images (VMSIs) was established in order to semi-automatically compute the aBMD at the spine similarly to DXA, using manual soft tissue segmentation, semi-automatic segmentation for the vertebrae, and automatic segmentation for the background. The method was assessed based on repetitive measurements of the standardized European Spine Phantom (ESP) using the standard scout scan tube current (30 mA) and other tube currents (10 to 200 mA), as well as using fat-equivalent extension rings simulating different patient habitus, and was compared to dual-energy X-ray absorptiometry (DXA). Moreover, the feasibility of the method was assessed in vivo in female patients.


Derived from standard scout scans, aBMD values measured with the proposed method significantly correlated with DXA measurements (r = 0.9925, p < 0.001), and mean accuracy (DXA, 4.12%; scout, 1.60%) and precision (DXA, 2.64%; scout, 2.03%) were comparable between the two methods. Moreover, aBMD values assessed at different tube currents did not differ significantly (p ≥ 0.20 for all), suggesting that the presented method could be applied to scout scans with different settings. Finally, data derived from sample patients were concordant with BMD values from a reference age-matched population.


Based on dual-layer spectral scout scans, aBMD measurements were fast and reliable and significantly correlated with the according DXA measurements in phantoms. Considering the number of CT acquisitions performed worldwide, this method could allow truly opportunistic osteoporosis screening.

Key Points

• 2D scout scans (localizer radiographs) from a dual-layer spectral CT scanner, which are mandatory parts of a CT examination, can be used to automatically determine areal bone mineral density (aBMD) at the spine.
• The presented method allowed fast (< 25 s/patient), semi-automatic, and reliable DXA-equivalent aBMD measurements for state-of-the-art DXA phantoms at different tube settings and for various patient habitus, as well as for sample patients.
• Considering the number of CT scout scan acquisitions performed worldwide on a daily basis, the presented technique could enable truly opportunistic osteoporosis screening with DXA-equivalent metrics, without involving higher radiation exposure since it only processes existing data that is acquired during each CT scan.

Bitte loggen Sie sich ein, um Zugang zu diesem Inhalt zu erhalten

e.Med Interdisziplinär

Mit e.Med Interdisziplinär erhalten Sie Zugang zu allen CME-Fortbildungen und Fachzeitschriften auf

Jetzt e.Med zum Sonderpreis bestellen!

Sichern Sie sich jetzt Ihr e.Med-Abo und sparen Sie 50 %!

Weitere Produktempfehlungen anzeigen
Über diesen Artikel

Weitere Artikel der Ausgabe 9/2019

European Radiology 9/2019 Zur Ausgabe
  1. Sie können e.Med Radiologie 14 Tage kostenlos testen (keine Print-Zeitschrift enthalten). Der Test läuft automatisch und formlos aus. Es kann nur einmal getestet werden.