Henry H. Ong1, Alexander C. Wright1,
Felix W. Wehrli1
1Laboratory for Structural NMR Imaging,
Department of Radiology, University of Pennsylvania School of Medicine,
Philadelphia, PA, United States
Magnetic
resonance is a powerful tool for non-destructive study of bone water, which
can provide insight into bone micro- and nanostructure. However, the MR
signal of bone is comprised of several proton populations including
collagen-associated water, and water within the pore space (Haversian and
lacuno-canalicular system). We hypothesize that water in pores is predominantly
free and water in the bone matrix is predominantly associated with collagen.
Using 2H exchange and inversion recovery experiments, we estimated porosity
in human cortical bone and found it to agree with micro-CT based volumetric
measurements with a significant fraction being collagen-associated.
Keywords