Abstract #3458

Excitation and Preparation Pulses Affect UTE Bi-Component Analysis of Bound and Free Water in Cortical Bone

Shihong Li¹,², Monica Tafur¹, Won C. Bae¹, Eric Chang¹, Christine Chung¹, Graeme M. Bydder³, Jiang Du¹

¹Radiology, University of California, San Diego, San Diego, CA, United States; ²Huadong Hospital, Fudan University, Shanghai, China; ³Radiology, University of California San Diego, San Diego, CA, United States

Biological tissues frequently contain distinct water compartments with different transverse relaxation times. Multi-component fitting techniques are important for realistic analysis of T2 relaxation curves. For cortical bone it is impractical to generate T2 relaxation curves using whole-body clinical MR systems due to the relatively long minimum TEs of spin echo sequences. It is much easier to generate T2* relaxation curves which potentially can be used to separate bound water with a shorter T2* from free water with a longer T2*. In this study we investigated the effect of excitation pulse shape, fat saturation pulse, long T2 saturation pulse and adiabatic inversion pulse on ultrashort echo time (UTE) bi-component analysis of bound and free water in bovine and human cortical bone samples.