Functional Imaging of Cartilage
Nondestructive techniques for accurately assessing the structural and functional integrity of cartilage are essential for defining the natural history of arthritis and for evaluating the effects of prevention and therapeutic interventions. Our long-term goal is to establish magnetic resonance imaging (MRI) techniques for evaluating the compositional and functional integrity of articular cartilage.
Cartilage is a dense connective tissue composed of a highly charged solid phase known as the extracellular matrix (ECM), an electrolyte fluid, and relatively few cells. Major ECM constituents include large proteoglycans, noncollagenous proteins, small proteoglycans, and collagen. The proteoglycans contain glycosaminoglycan (GAG) sidechains, and have the appearance of a "bottle brush" structure. Collagen fibrils form the tissue network. We have been concentrating on techniques to image these two main components of the cartilage matrix, glycosaminoglycans (GAG) and collagen.
These imaging techniques should enable the unprecedented opportunity to nondestructively monitor the spatial distribution and temporal evolution of critical cartilage constituents in living tissue at near-histologic resolution in isolated cartilage and at clinically relevant resolutions in vivo, studies which were previously not feasible.