Repeatability of ZTE Bone Maps of the Head

The goal of this paper was to assess the longitudinal repeatability of a bone identification method, based on the zero-echo-time MRI pulse sequence. The consistency of the bone maps-with potential applications in magnetic resonance-based attenuation correction of positron emission tomography data-was evaluated for a number of clinically realistic variations of the ideal acquisition conditions. The method was shown to be generally repeatable, with differences in the ±1% range. A number of potential issues were identified (e.g., sinus post-processing region placement variability, false positive bone structures near sharp coil sensitivity transitions, and axial coil coverage limitations) and mitigation strategies designed.