Implications of Soft-Tissue Suppression on Cortical Bone Water Signal in Ultrashort Echo-Time Imaging

Maximilian James Smith¹, Cheng Li¹, Yusuf A. Bhagat¹, Shing Lam¹, James H. Love¹, Felix W. Wehrli¹

The use of soft-tissue suppression in UTE imaging unavoidably suppresses a fraction of the bone water signal. Importantly, bone water suppression may not be uniform throughout the cortex, given that pore size increases from the periosteum to the endosteum and that T2 is likely lengthened in larger pores. We employ in vivo UTE imaging of the mid-tibia with and without soft-tissue suppression to determine the degree of bone water suppression within different regions of cortex. Suppression of cortical bone water varied with location in the cortex and appears to be age-dependent, potentially confounding measures of bone water concentration.