title: Functional brain imaging using a long intravenous half-life gadolinium-based contrast agent.
abstract: OBJECTIVE
  We describe a technique for functional MR imaging (fMRI) with high spatial and temporal resolution using a long intravascular half-life gadolinium-based contrast agent, MS-325.
  
  
  METHODS
  All fMRI measurements used a rat model of sensory cortex activation with forepaw electrical stimulation under alpha-chloralose anesthesia. Standard blood oxygen level-dependent (BOLD) fMRI measurement was initially performed. MS-325 was then intravenously administered and a MS-325 fMRI measurement was performed by using a 3D gradient-echo sequence.
  
  
  RESULTS
  We found that a dose of 0.1 mmol/kg MS-325 produced adequate signal intensity changes in rat sensory cortex to demonstrate activations. Using a boxcar stimulation pattern with a standard correlation analysis, the locations of the most significantly activated voxels (ie, highest Z score) in the MS-325 and BOLD fMRI measurements were not significantly different.
  
  
  CONCLUSIONS
  MS-325 fMRI has the advantage of using a T1-weighted sequence, rather than the highly T2*-weighted sequences used in other common fMRI techniques. This could reduce the susceptibility artifacts associated with fMRI.
authors.affiliation: Department of Radiology, University of Washington, 1959 NE Pacific Street, Seattle, WA 98195, USA.
authors.forename: D W
authors.initials: DW
authors.lastname: Morton
authors.forename: B
authors.initials: B
authors.lastname: Keogh
authors.forename: K
authors.initials: K
authors.lastname: Lim
authors.forename: K R
authors.initials: KR
authors.lastname: Maravilla
mesh_terms: D000818:Animals; D003287:Contrast Media / Q000008:administration & dosage*; D004558:Electric Stimulation; D005240:Feasibility Studies; D005528:Foot / Q000294:innervation; D005682:Gadolinium / Q000008:administration & dosage; D006207:Half-Life; D007089:Image Enhancement / Q000379:methods; D021621:Imaging, Three-Dimensional / Q000379:methods; D007275:Injections, Intravenous; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D009942:Organometallic Compounds / Q000008:administration & dosage; D051381:Rats; D017207:Rats, Sprague-Dawley; D013003:Somatosensory Cortex / Q000502:physiology*
chemical_list: D003287:Contrast Media; D009942:Organometallic Compounds; D005682:Gadolinium; C109932:gadofosveset trisodium