Impact of Hardware Timing Errors on Quantification of Bone Water with UTE and ZTE

Radial MR sequences are sensitive to system timing errors, particularly for ultra-short echo time (UTE) and zero echo time (ZTE) techniques. The effects of these timing errors on image quality were systematically evaluated with both simulation and imaging experiments, and their impact on bone water quantification investigated in vivo. Error in bone water concentration in the mid-tibia was found to be up to 35.4% using UTE and 16.6% for ZTE in the presence of timing errors as small as 6 μs. Further, the severity of image artifacts were spatially dependent, with objects further from FOV center more highly distorted.