title: Preliminary observations of transverse relaxation rates obtained at 3 tesla from the substantia nigra of adult normal human brain.
abstract: The transverse relaxation rates R2 and R2* were measured at 3 T in the substantia nigra of the midbrain of adult normal human controls. The relaxation rate arising from magnetic inhomogeneities, R2', was calculated from the relationship R2* = R2 + R2'. No significant differences were found for any parameters between left and right side substantia nigra regions, however, a significant inverse correlation was found between R2 and R2' (r = 0.70, p = 0.035). Water diffusion, in the presence of paramagnetic metal ions, may play a role in determining the relative contributions to reversible and irreversible transverse relaxation and may explain the inverse correlation demonstrated here.
authors.affiliation: Department of Neurology, Henry Ford Hospital and Health Sciences Center, Detroit, MI, USA.
authors.forename: J A
authors.initials: JA
authors.lastname: Helpern
authors.forename: R J
authors.initials: RJ
authors.lastname: Ordidge
authors.forename: J M
authors.initials: JM
authors.lastname: Gorell
authors.forename: J C
authors.initials: JC
authors.lastname: Deniau
authors.forename: K M
authors.initials: KM
authors.lastname: Welch
mesh_terms: D000368:Aged; D006801:Humans; D007501:Iron / Q000032:analysis; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008875:Middle Aged; D013378:Substantia Nigra / Q000033:anatomy & histology*
chemical_list: D007501:Iron