Objective: Imaging studies of patients with bipolar disorder demonstra
te changes in deep white matter and subcortical gray nuclei that are s
een as focal hyperintensities on T-2-weighted magnetic resonance imagi
ng (MRI). The objective of this study was to examine MRIs in a family
with a strong history of bipolar disorder to look for possible MRI abn
ormalities in members with and without affective illness. Method: The
authors obtained MRIs of 21 members of a family with a strong history
of bipolar disorder. Eight of the family members studied had bipolar i
llness, one had symptoms of bipolar disorder but did not meet full DSM
-III-R criteria, two had unipolar disorder, and 10 did not have bipola
r disorder. Results: Fifteen of the 21 family members had MRI findings
, including six of 10 family members who had no affective disorder and
all of those with bipolar disorder. Lesions of both white matter and
subcortical gray nuclei were found. Conclusions: Although the clinical
significance of these MRI findings is unknown, the high prevalence of
MRI findings in both affected and unaffected family members suggests
that MRI findings may potentially serve as a biological marker for bip
olar disorder. Recent genetic studies have established a link between
familial leukoencephalopathy and chromosome 19. If leukoencephalopathy
appears to be related to bipolar disorder, it may allow clearer chara
cterization of the genetics of the disorder.