title: Brain T2 relaxation times correlate with regional cerebral blood volume.
abstract: We previously reported cerebellar and putaminal transverse relaxation time (T2) differences in children with ADHD and in adults with childhood trauma. As brain T2 can be altered by deoxyhemoglobin concentration ([dHb]) and because [dHb] is proportional to regional cerebral blood volume (rCBV), at steady state we attributed those differences to rCBV changes. Studies in other species have established a correlation between T2 and rCBV; however this has yet to be demonstrated in human brain. Echo planar imaging (EPI) T2 relaxometry and dynamic susceptibility-contrast (DSC) MRI were used to measure T2 and rCBV in 11 healthy adults. Significant T2-rCBV correlations were observed in both cerebellar vermis and putamen (r = 0.759,p = 0.007;r = 0.782,p = 0.004, respectively). These correlations predict 9 +/- 3% and 10 +/- 3% rCBV changes, respectively, for each 1-msec change in T2. Consequently, brain T2 measurements may be useful for estimating steady-state rCBV.
authors.affiliation: Department of Psychiatry, Harvard Medical School, Boston, MA, USA. carl_anderson@hms.harvard.edu
authors.forename: C M
authors.initials: CM
authors.lastname: Anderson
authors.forename: M J
authors.initials: MJ
authors.lastname: Kaufman
authors.forename: S B
authors.initials: SB
authors.lastname: Lowen
authors.forename: M
authors.initials: M
authors.lastname: Rohan
authors.forename: P F
authors.initials: PF
authors.lastname: Renshaw
authors.forename: M H
authors.initials: MH
authors.lastname: Teicher
mesh_terms: D000293:Adolescent; D000328:Adult; D001810:Blood Volume / Q000502:physiology; D001921:Brain / Q000098:blood supply / Q000502:physiology; D002531:Cerebellum / Q000098:blood supply* / Q000502:physiology*; D002560:Cerebrovascular Circulation / Q000502:physiology*; D003287:Contrast Media; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D011699:Putamen / Q000098:blood supply* / Q000502:physiology*; D013223:Statistics as Topic
chemical_list: D003287:Contrast Media