title: High-resolution sodium imaging of human brain at 7 T.
abstract: The feasibility of high-resolution sodium magnetic resonance imaging on human brain at 7 T was demonstrated in this study. A three-dimensional anisotropic resolution data acquisition was used to address the challenge of low signal-to-noise ratio associated with high resolution. Ultrashort echo-time sequence was used for the anisotropic data acquisition. Phantoms and healthy human brains were studied on a whole-body 7-T magnetic resonance imaging scanner. Sodium images were obtained at two high nominal in-plane resolutions (1.72 and 0.86 mm) at a slice thickness of 4 mm. Signal-to-noise ratio in the brain image (cerebrospinal fluid) was measured as 14.4 and 6.8 at the two high resolutions, respectively. The actual in-plane resolution was measured as 2.9 and 1.6 mm, 69-86% larger than their nominal values. The quantification of sodium concentration on the phantom and brain images enabled better accuracy at the high nominal resolutions than at the low nominal resolution of 3.44 mm (measured resolution 5.5 mm) due to the improvement of in-plane resolution.
authors.affiliation: MR Research Center, Department of Radiology, University of Pittsburgh, Pittsburgh, Pennsylvania, USA. qiany@upmc.edu
authors.forename: Yongxian
authors.initials: Y
authors.lastname: Qian
authors.forename: Tiejun
authors.initials: T
authors.lastname: Zhao
authors.forename: Hai
authors.initials: H
authors.lastname: Zheng
authors.forename: Jonathan
authors.initials: J
authors.lastname: Weimer
authors.forename: Fernando E
authors.initials: FE
authors.lastname: Boada
mesh_terms: D000328:Adult; D000465:Algorithms; D001921:Brain / Q000033:anatomy & histology / Q000378:metabolism*; D003287:Contrast Media / Q000493:pharmacokinetics; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012964:Sodium / Q000493:pharmacokinetics*; D014018:Tissue Distribution; D055815:Young Adult
chemical_list: D003287:Contrast Media; D012964:Sodium