Anisotropy of spin relaxation of water protons in cartilage and tendon


Autoria(s): Momot, Konstantin I.; Pope, James M.; Wellard, R. Mark
Data(s)

01/04/2010

Resumo

Transverse spin relaxation rates of water protons in articular cartilage and tendon depend on the orientation of the tissue relative to the applied static magnetic field. This complicates the interpretation of magnetic resonance images of these tissues. At the same time, relaxation data can provide information about their organisation and microstructure. We present a theoretical analysis of the anisotropy of spin relaxation of water protons observed in fully hydrated cartilage. We demonstrate that the anisotropy of transverse relaxation is due almost entirely to intramolecular dipolar coupling modulated by a specific mode of slow molecular motion: the diffusion of water molecules in the hydration shell of a collagen fibre around the fibre, such that the molecular director remains perpendicular to the fibre. The theoretical anisotropy arising from this mechanism follows the “magic-angle” dependence observed in magnetic-resonance measurements of cartilage and tendon and is in good agreement with the available experimental results. We discuss the implications of the theoretical findings for MRI of ordered collagenous tissues.

Identificador

http://eprints.qut.edu.au/27317/

Publicador

John Wiley & Sons

Relação

DOI:10.1002/nbm.1466

Momot, Konstantin I., Pope, James M., & Wellard, R. Mark (2010) Anisotropy of spin relaxation of water protons in cartilage and tendon. NMR in Biomedicine, 23(3), pp. 313-324.

Direitos

Copyright 2010 John Wiley & Sons

The definitive version is available at www3.interscience.wiley.com

Fonte

Faculty of Science and Technology

Palavras-Chave #029903 Medical Physics #029901 Biological Physics #cartilage #Redfield spin relaxation theory #magnetic resonance imaging #tendon #rotational diffusion propagator #nuclear magnetic resonance
Tipo

Journal Article