Anatomic brain magnetic resonance imaging of the basal ganglia in pediatric bipolar disorder.
BACKGROUND
Basal ganglia (BG) enlargement has been found in studies of adults with bipolar disorder (BPD), while the few studies of BPD youths have had mixed findings. The BG (caudate, putamen, globus pallidus, nucleus accumbens) is interconnected with limbic and prefrontal cortical structures and therefore may be implicated in BPD.


METHODS
Sixty-eight youths (46 with BPD, 22 healthy controls) received neurological and psychiatric assessment, semi-structured interviews, and neuropsychological testing, followed by anatomic magnetic resonance imaging on a 1.5 Tesla scanner. After image segmentation, log BG volumes and asymmetry indices were analyzed using MANOVAs controlling for the effects of cerebral volume, age, sex, and diagnosis. These omnibus tests were followed by univariate linear regression models of each BG structure.


RESULTS
Youths with BPD had a trend for larger right nucleus accumbens (NA) volumes (p = 0.089). There were no significant group asymmetry differences, nor volume differences in the caudate, putamen, and globus pallidus. When analyzed separately by pubertal status, the prepubertal group had significantly larger total NA (p = 0.035) versus healthy controls, while the pubertal group did not show significant differences in the NA versus healthy controls.


CONCLUSIONS
The size of the control group is relatively small, possibly limiting our power to detect significant group differences. The inter-rater reliability for the NA is not as strong as the other structures; the finding of volume differences in this structure is preliminary and warrants replication.


CONCLUSIONS
Youths with BPD had larger right NA volumes; this enlargement was most pronounced in the prepubertal group. The differences between these findings and those seen in adult BPD imply a neurodevelopmental phenomenon.
Ahn
Mary S
MS
Cambridge Health Alliance Department of Psychiatry 1493 Cambridge St. Cambridge, MA 02139, USA.
Breeze
Janis L
JL
Makris
Nikos
N
Kennedy
David N
DN
Hodge
Steven M
SM
Herbert
Martha R
MR
Seidman
Larry J
LJ
Biederman
Joseph
J
Caviness
Verne S
VS
Frazier
Jean A
JA
D000293:Adolescent; D001479:Basal Ganglia / Q000033:anatomy & histology*; D001714:Bipolar Disorder / Q000175:diagnosis* / Q000453:epidemiology; D002421:Caudate Nucleus / Q000033:anatomy & histology; D002648:Child; D003072:Cognition Disorders / Q000175:diagnosis / Q000453:epidemiology; D005260:Female; D005917:Globus Pallidus / Q000033:anatomy & histology; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009483:Neuropsychological Tests; D009714:Nucleus Accumbens / Q000033:anatomy & histology; D011699:Putamen / Q000033:anatomy & histology