NMR proton T1 and T2 relaxation times from fresh, in vitro canine tissues at 5.1 MHz.

Few measures of proton T1 and T2 of normal tissues performed at frequencies useful for NMR imaging have been reported. In these experiments, relaxation times were determined on a wide range of fresh canine tissues in a homogeneous field of 0.15 Tesla where the Larmour frequency for protons is 5.1 MHz. Despite similar proton densities, tissue T1 and T2 relaxation times differ strikingly. These differences allow tissue differentiation by NMR imaging although the biological basis for the different proton relaxation times from one tissue to the next is not yet understood.