The different T2 components composing an MRI signal will, in many cases, reflect the underlying classification of tissues. One simplified model is given by the two-component case of fat and water. The characterization of fat is relevant for the study of many organs and physiological functions including the liver and pancreas, the heart, breast, and general body metabolism. Another major area of interest is the musculoskeletal system, and specifically, the investigation of muscular pathologies such as dystrophy, or neuromuscular disorders.
Mapping the T2 relaxation values can be highly valuable in this case as it can provide information regarding the relative content of fat and water in the tissue. One example is the Charcot-Marie-Tooth (CMT) disease, characterized by infiltration of fat into the muscle as a result of tissue atrophy. Based on quantitative MRI measurements we develop techniques for fast assessment of fat and water content in vivo, and use these for investigating pathologies in adipose tissues.
Representative axial slices of the thigh and calf in a CMT patient. (A&D) standard T2 map w/o fat water separation; (B&E) T2 map for water component only; (C&F) Fat fraction map (1 – water fraction).
Applications of this technique include probing fat infiltration into the muscle in Charcot-Marie Tooth disease, monitoring fat levels in liver tissue, separation between white and brown fat and more.