Does the Trabecular Bone Structure Depicted by High-Resolution MRI of the Calcaneus Reflect the True Bone Structure?

Vieth V, Link TM, Lotter A, et al. Does the trabecular bone structure depicted by high-resolution MRI of the calcaneus reflect the true bone structure? Invest Radiol 2001;36:210–217. RATIONALE AND OBJECTIVES. The purpose of this study was to compare trabecular bone structure parameters assessed with high-resolution magnetic resonance imaging (HR-MRI) with those determined in specimen sections. METHODS.High-resolution MR images were obtained for 30 calcaneus specimens with a three-dimensional, T1-weighted spin-echo sequence (spatial in-plane resolution 0.195 mm, slice thicknesses of 0.3 and 0.9 mm). Thirty-eight sections were obtained from the specimens, and contact radiography was performed. In the corresponding sections, structural parameters analogous to bone histomorphometry were determined. RESULTS.Significant correlations between MRI-derived structural parameters and those derived from macro pathological sections were found:r values of up to 0.75 were obtained (P < 0.01). The highest correlations were found for apparent bone volume/total volume and trabecular thickness. Image thresholding techniques showed a significant impact on these correlations (P < 0.01). The thinner MR sections were less susceptible to the different thresholding algorithms. CONCLUSIONS.Trabecular bone structure depicted by HR-MR images is significantly correlated with that shown in macro sections (P < 0.01); however, a number of limitations have to be considered, including the substantial impact of thresholding techniques and slice thickness.