title: Chemical shift sodium imaging in a mouse model of thromboembolic stroke at 9.4 T.
abstract: OBJECTIVE
  To estimate changes in the (23)Na density and in the (23)Na relaxation time T(2) * in the anatomically small murine brain after stroke.
  
  
  METHODS
  Three-dimensional acquisition weighted chemical shift imaging at a resolution of 0.6 × 0.6 × 1.2 mm(3) was used for sodium imaging and relaxation parameter mapping. In vivo measurements of the mouse brain (n = 4) were performed 24 hours after stroke, induced by microinjection of purified murine thrombin into the right middle cerebral artery. The measurement time was 14 minutes in one mouse and 65 minutes in the other three. An exponential fit estimation of the free induction decay was calculated for each voxel enabling the reconstruction of locally resolved relaxation parameter maps.
  
  
  RESULTS
  The infarcted areas showed an increase in sodium density between 160% and 250%, while the T(2) * relaxation time increased by 5%-72% compared to unaffected contralateral brain tissue.
  
  
  CONCLUSIONS
  (23)Na chemical shift imaging at a resolution of 0.6 × 0.6 × 1.2 mm(3) enabled sodium imaging of the anatomical small mouse brain and the acquired data allowed calculating relaxation parameter maps and hence a more exact evaluation of sodium signal changes after stroke.
authors.affiliation: Computer Assisted Clinical Medicine, Heidelberg University, Mannheim, Germany. patrick.heiler@medma.uni-heidelberg.de
authors.forename: Patrick M
authors.initials: PM
authors.lastname: Heiler
authors.forename: Friederike L
authors.initials: FL
authors.lastname: Langhauser
authors.forename: Friedrich
authors.initials: F
authors.lastname: Wetterling
authors.forename: Saema
authors.initials: S
authors.lastname: Ansar
authors.forename: Saskia
authors.initials: S
authors.lastname: Grudzenski
authors.forename: Simon
authors.initials: S
authors.lastname: Konstandin
authors.forename: Marc
authors.initials: M
authors.lastname: Fatar
authors.forename: Stephen
authors.initials: S
authors.lastname: Meairs
authors.forename: Lothar R
authors.initials: LR
authors.lastname: Schad
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D005240:Feasibility Studies; D007091:Image Processing, Computer-Assisted; D021621:Imaging, Three-Dimensional; D020244:Infarction, Middle Cerebral Artery / Q000175:diagnosis* / Q000473:pathology; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D019047:Phantoms, Imaging; D011897:Random Allocation; D012680:Sensitivity and Specificity; D012964:Sodium / Q000378:metabolism*; D020521:Stroke / Q000175:diagnosis* / Q000473:pathology
chemical_list: D012964:Sodium