Normal brain maturation characterized with age-related T2 relaxation times: an attempt to develop a quantitative imaging measure for clinical use.
OBJECTIVE
We studied age-related changes in T2 relaxation times from the normal maturating human brain under routine clinical MR examination conditions.


METHODS
In 70 healthy subjects aged between 3 weeks and 39 years, T2 maps of the brain in which the intensity of each pixel corresponded to T2 relaxation times were generated based on magnetic resonance imaging data collected with a triple spin echo sequence. T2 relaxation times in white matter (WM) and gray matter (GM) were measured in 6 distinctive regions of interest of the T2 maps. The age dependence of the T2 values was mathematically simulated using a biexponential function.


RESULTS
T2 values were largest at the age of 3 weeks (maximum: approximately 400 milliseconds for WM and 200 milliseconds for GM) and decreased continuously with increasing age, faster in the first few months and slower thereafter, until values achieved between 95 and 110 milliseconds for WM and 88 and 95 milliseconds for GM in adults. The relationship between T2 values and age could be well simulated using a biexponential function (R > 0.92).


CONCLUSIONS
T2 relaxation time correlates well with the progress of brain maturation. The used biexponential function reflects the dynamic development of myelination in newborns and young children as well as the maturation of myelination during adolescence and could be used to develop a "normal" reference for neuroradiological diagnoses.
Ding
Xiao-Qi
XQ
Department of Neuroradiology, University Hospital Hamburg-Eppendorf, University of Hamburg, Germany. ding@uke.uni-hamburg.de
Kucinski
Thomas
T
Wittkugel
Oliver
O
Goebell
Einar
E
Grzyska
Ulrich
U
Görg
Maria
M
Kohlschütter
Alfried
A
Zeumer
Hermann
H
D000328:Adult; D000367:Age Factors; D001921:Brain / Q000033:anatomy & histology* / Q000254:growth & development*; D002648:Child; D002675:Child, Preschool; D005240:Feasibility Studies; D006801:Humans; D007223:Infant; D008279:Magnetic Resonance Imaging; D012016:Reference Values