Non-exponential transverse relaxation in the brain’s basal ganglia

Non-exponential transverse relaxation in the brain’s basal ganglia has been investigated in theoretical studies but little evidence from in-vivo MRI data exists in support of this behaviour. Here, we provide experimental observation of non-exponential transverse relaxation in-vivo MRI data in the basal ganglia at 3T. The strongest deviations from exponential behaviour take place in the iron-rich pallidum and substantia nigra. Our results suggest that water diffusion through the inhomogeneous magnetic field induced by paramagnetic iron deposits may be at the source of non-exponential transverse relaxation in the basal ganglia.