title: Investigations on the effect of caffeine on cerebral venous vessel contrast by using susceptibility-weighted imaging (SWI) at 1.5, 3 and 7 T.
abstract: Caffeine lowers the blood oxygenation level-dependent (BOLD) signal by acting as an adenosine antagonist, thus decreasing the cerebral blood flow (CBF). The aims of this study were to demonstrate the sensitivity of susceptibility-weighted imaging (SWI) to caffeine-induced changes in CBF and to investigate the time course and magnitude of signal change in caffeine-habituated and -abstinent volunteers. High-resolution susceptibility-weighted images were acquired with both groups at 1.5 T using a fully velocity compensated 3D gradient echo sequence. Following a native scan, subjects were given a tablet containing 200 mg of caffeine. Scans were repeated for about 1 h and the acquired 3D data sets were co-registered to each other. BOLD signal changes of several venous vessels were analyzed in dedicated ROIs. Maps of relative signal change clearly visualized the caffeine-induced signal response of veins. Only very weak signal changes of about -2+/-1% were found in both, grey and white matter and -1+/-2% in the ventricles. Maximum signal decrease of veins occurred 40-50 min after caffeine ingestion. The signal decrease was -16.5+/-6.5% and -22.7+/-8.3% for the caffeine users group and abstainers, respectively. The signal difference of both groups was statistically significant (Student's t-test, t=2.16, p=0.021). Data acquired at 1.5, 3 and 7 T with echo times scaled to the respective field strength display very similar temporal signal behavior.
authors.affiliation: Medical Physics Group, Institute of Diagnostic and Interventional Radiology, Friedrich Schiller University, Philosophenweg 3, Jena, Germany.
authors.forename: Jan
authors.initials: J
authors.lastname: Sedlacik
authors.forename: Katharina
authors.initials: K
authors.lastname: Helm
authors.forename: Alexander
authors.initials: A
authors.lastname: Rauscher
authors.forename: Jörg
authors.initials: J
authors.lastname: Stadler
authors.forename: Hans-Joachim
authors.initials: HJ
authors.lastname: Mentzel
authors.forename: Jürgen R
authors.initials: JR
authors.lastname: Reichenbach
mesh_terms: D000328:Adult; D002110:Caffeine / Q000494:pharmacology*; D000697:Central Nervous System Stimulants / Q000494:pharmacology*; D002550:Cerebral Veins / Q000033:anatomy & histology* / Q000187:drug effects; D002552:Cerebral Ventricles / Q000033:anatomy & histology / Q000187:drug effects; D003627:Data Interpretation, Statistical; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D010100:Oxygen / Q000097:blood
chemical_list: D000697:Central Nervous System Stimulants; D002110:Caffeine; D010100:Oxygen