Performance comparison of the spatial autocorrelation function and the mean intercept-length in the determination of trabecular bone anisotropy in the in vivo environment
Saha P, Wehrli F, Vasilic B, Wald M
Department of Radiology, University of Pennsylvania Medical Center
Recent research suggests that structure contributes to bone strength in a manner complementary to bone mineral density. Besides parameters of scale such as trabecular bone thickness and volume fraction, the trabeculae are oriented preferentially along the major stress lines, leading to an angular dependence of such parameters as trabecular separation. The structural anisotropy is of pivotal importance to the bones mechanical competence and is most commonly characterized by the mean-intercept-length (MIL) method. Here, we investigate the performance of the spatial autocorrelation function, a threshold-independent approach, as an alternative method that we hypothesized had significant advantages over the MIL technique with respect to in vivo imaging.