title: Contrast optimization of Macaca mulatta basal ganglia in magnetic resonance images at 4.7 Tesla.
abstract: To determine whether high field MRI could distinguish among the different regions of the basal ganglia, the brains of two Macaca mulatta monkeys were explored in vivo using a 4.7 T MR imager. Gradient-echo (GE) and spin-echo images were acquired with proton-density, T1 and T2* weightings. Five GE images with increased susceptibility effects were generated using a GESFID sequence, from which T2* maps were also reconstructed. The first echo of the GESFID sequence (TE = 12.6 ms) produced the best contrast-to-noise ratio (C/N) between the pallidum and the putamen, the pallidum and the thalamus, the substantia nigra and the surrounding white matter, and the substantia nigra and the subthalamic nucleus. An increased T2*-weighting (TE = 37.2 ms) was necessary to maximize C/N between the putamen and the surrounding white matter, and between the subthalamic nucleus and the surrounding white matter. A dual GE sequence with a short TE ( approximately 10 ms) and a longer one ( approximately 30 ms) thus effectively localizes basal ganglia subregions at 4.7 T.
authors.affiliation: Unité STIM, INRA, THEIX- 63122, Saint-Genès Champanelle, France. bonny@clermont.inra.fr
authors.forename: J
authors.initials: J
authors.lastname: Bonny
authors.forename: F
authors.initials: F
authors.lastname: Durif
authors.forename: J E
authors.initials: JE
authors.lastname: Bazin
authors.forename: E
authors.initials: E
authors.lastname: Touraille
authors.forename: J
authors.initials: J
authors.lastname: Yelnik
authors.forename: J P
authors.initials: JP
authors.lastname: Renou
mesh_terms: D000818:Animals; D001479:Basal Ganglia / Q000033:anatomy & histology* / Q000502:physiology; D005260:Female; D007091:Image Processing, Computer-Assisted; D008253:Macaca mulatta / Q000033:anatomy & histology* / Q000502:physiology; D008279:Magnetic Resonance Imaging; D009413:Nerve Fibers, Myelinated / Q000502:physiology / Q000648:ultrastructure; D012815:Signal Processing, Computer-Assisted; D013378:Substantia Nigra / Q000033:anatomy & histology / Q000502:physiology; D020531:Subthalamic Nucleus / Q000033:anatomy & histology / Q000502:physiology; D013788:Thalamus / Q000033:anatomy & histology / Q000502:physiology