Bone structure determined by HR-MDCT does not correlate with micro-CT of lumbar vertebral biopsies: a prospective cross-sectional human in vivo study

Abstract

Background Osteoporosis is characterized by a deterioration of bone structure and quantity that leads to an increased risk of fractures. The primary diagnostic tool for the assessment of the bone quality is currently the dual-energy X-ray absorptiometry (DXA), which however only measures bone quantity. High-resolution multidetector computed tomography (HR-MDCT) offers an alternative approach to assess bone structure, but still lacks evidence for its validity in vivo. The objective of this study was to assess the validity of HR-MDCT for the evaluation of bone architecture in the lumbar spine. Methods We conducted a prospective cross-sectional study to compare the results of preoperative lumbar HR-MDCT scans with those from microcomputed tomography (μCT) analysis of transpedicular vertebral body biopsies. For this purpose, we included patients undergoing spinal surgery in our orthopedic department. Each patient underwent preoperative HR-MDCT scanning (L1-L4). Intraoperatively, transpedicular biopsies were obtained from intact vertebrae. Micro-CT analysis of these biopsies was used as a reference method to assess the actual bone architecture. HR-MDCT results were statistically analyzed regarding the correlation with results from μCT. Results Thirty-four patients with a mean age of 69.09 years (± 10.07) were included in the study. There was no significant correlation for any of the parameters (bone volume/total volume, trabecular separation, trabecular thickness) between μCT and HR-MDCT (bone volume/total volume: r = − 0.026 and p = 0.872; trabecular thickness: r = 0.074 and r = 6.42; and trabecular separation: r = − 0.18 and p = 0.254). Conclusion To our knowledge, this is the first study comparing in vivo HR-MDCT with μCT analysis of vertebral biopsies in human patients. Our findings suggest that lumbar HR-MDCT is not valid for the in vivo evaluation of bone architecture in the lumbar spine. New diagnostic tools for the evaluation of osteoporosis and preoperative orthopedic planning are urgently needed.

Evaluation of Trabecular Microstructure of Cancellous Bone Using Quarter-Detector Computed Tomography

“…In our study, the regression coefficient of BV/TV was similar to that of BS and consistent with the BV calculation method. Our results indicated improved measurement precision compared to conventional MDCT [ 39 ]. QDCT can serve as evidence for adequate spatial resolution to obtain measurement values equivalent to those obtained for trabecular structure analysis using micro-CT.…”

Dose-efficient assessment of trabecular microstructure using ultra-high-resolution photon-counting CT

“…In a recent publication of an in vivo study, Pumberger et al [12] used vertebral biopsies with trabecular bone and compared µCT derived trabecular measurements with those obtained from the pre-operative CT scans of the patients but they did not report correlations between MSCT- and µCT-derived trabecular structure variables. Presumably, this could be explained by a number of factors: they stated that their CT protocol included voxel sizes of 0.5×0.5×0.5 mm 3 , which were coarser than voxel sizes used in other HR-MSCT studies (0.156×0.156×0.3 mm 3 ) [20] ; the volume of the biopsies, although not stated in the mentioned publication, may not have been large enough to yield robust correlations with µCT.…”

“…High resolution MRI can target trabecular bone structure in vivo at the central skeleton [11] but does not yield mineral density information and the relatively long scan times often result in image artifacts that complicate (but not impede) quantitative analysis. On the other hand, dual X-ray absorptiometry (DXA), a 2D projectional imaging technique, is the current radiological standard to estimate fracture risk and determine treatment pathways to follow on osteoporotic patients [10] , [12] . DXA is slow in reflecting improvements in bone strength after (bisphosphonate) treatment and is only a poor predictor of fracture status in osteoporotic male patients with secondary osteoporosis [13] .…”

Association of bone-related biomarkers with femoral neck bone strength

“…Finally, the current research has mostly focused on the correlation between bone-related biomarkers and bone mineral density, and has not been extensively studied on bone strength. BMD only explain about 60—70% of the variation in bone strength [ 18 ], and mere correlation analysis of biomarkers with BMD does not well reflect changes in bone strength, which may be detrimental to our clinical guidance more comprehensively.…”