Direct depiction of bone microstructure using MRI with zero echo time

This paper reports a proof of principle of direct depiction of trabecular bone microstructure in vitro by means of magnetic resonance imaging (MRI). Such depiction is achieved by H-1 imaging of water embedded in the bone matrix. The fast transverse relaxation of this compartment with T-2* on the order of a few hundreds of microseconds is addressed by a three-dimensional MRI technique with zero echo time (ZTE). ZTE imaging at an isotropic spatial resolution of 56 mu m is demonstrated in a trabecular bone specimen extracted from a bovine bone. In the MR images, the trabecular bone structure is clearly depicted and a high level of robustness against off-resonance artefacts is observed. The structural accuracy of the MR data is investigated by comparison with x-ray micro-computed tomography. (C) 2013 Elsevier Inc. All rights reserved.