Imaging Modalities

Bone imaging is typically used to assess BMD, morphology, or microstructure. Imaging modalities that are used for bone health assessment include dual-energy X-ray absorptiometry (DXA), dual-energy photon absorptiometry (DPA), and standard and high-resolution peripheral quantitative computed tomography (pQCT, HR-pQCT). Nevertheless, the availability of pQCT scanners is mainly limited to research institutions in part due to the incompatibility of pQCT data with DXA-derived T-scores, lack of normative studies, and specific treatment thresholds (Engelke et al. 2008, Adams et al. 2014, Zysset et al. 2015). There are more than 50,000 whole-body DXA, approximately 800 pQCT (XCT 2000 and 3000) and just 50 HR-pQCT (XtremeCT and XtremeCT II) scanners used in clinical practice/research worldwide (Shepherd et al. 2014; personal communication with Stratec Medizintechnik GmbH and Scanco Medical).