Relaxation mechanisms in collagen rich tissues
نویسنده
چکیده
Collagen Hydration Collagen has a high degree of water absorption due to the process of collagen hydration. In tissue such as cartilage and tendon, the water forms a hydrogen-bonded chains running parallel to the axis of long collagen molecule. The overall model of water hydration involves the chain-like inner hydration layer, in which the water molecules are hydrogenbonded to the collagen and several outer layers which are considerably more mobile (1). In consequence, the magnetic resonance properties of water in collagen-rich structures are highly heterogeneous and complex. In particular, water exhibits multiple resonance frequencies due to different chemical environment of inner and outer shells (2). Since MR signal strongly depends on water mobility and interactions between water protons and collagen hydrogen atoms, collagen-rich structures have very interesting T2 relaxation properties and high degree of magnetization transfer effect.
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