Age-related changes in regional brain volume evaluated by atlas-based method.
BACKGROUND
The effects of aging on brain volume are generally investigated using voxel-based morphometry (VBM) or the manually traced region-of-interest (ROI) method. We introduce an atlas-based method as a methodological alternative that calculates absolute volume as a non-biased and semi-automatic whole-brain technique.


METHODS
We enrolled 115 healthy females (mean age, 36.7 years) and 130 healthy males (mean age, 37.1 years). Volume data were acquired using a 1.5 tesla magnetic resonance scanner. After spatial normalization, a lobar-based atlas template was applied, and the absolute volumes of the frontal, temporal, parietal, and occipital lobes and the sublobar and limbic areas were calculated bilaterally. The effects of age on regional brain volume were evaluated statistically.


RESULTS
The volume of all ROIs declined linearly with increasing age. The bilateral frontal lobes showed the steepest involution. Analysis of variance revealed significant laterality and interaction of gender and age.


CONCLUSIONS
The atlas-based method introduced in the present study has advantages over the manually traced ROI method in its objectivity, coverage, and time requirement and has an advantage over the VBM method in its computability of absolute volume. The results are largely in agreement with those reported previously, thereby reconfirming the importance of matching gender and age in analyzing brain disorders.
Gonoi
Wataru
W
Department of Radiology, Graduate School of Medicine, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8655, Japan. watapi-tky@umin.ac.jp
Abe
Osamu
O
Yamasue
Hidenori
H
Yamada
Haruyasu
H
Masutani
Yoshitaka
Y
Takao
Hidemasa
H
Kasai
Kiyoto
K
Aoki
Shigeki
S
Ohtomo
Kuni
K
D000328:Adult; D000368:Aged; D000375:Aging / Q000473:pathology* / Q000502:physiology*; D001921:Brain / Q000033:anatomy & histology* / Q000254:growth & development*; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009929:Organ Size / Q000502:physiology; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012737:Sex Factors; D013382:Subtraction Technique; D055815:Young Adult