TY - JOUR
T1 - Tract-specific white matter structural disruption in patients with bipolar disorder
AU - Benedetti, Francesco
AU - Absinta, Martina
AU - Rocca, Maria A.
AU - Radaelli, Daniele
AU - Poletti, Sara
AU - Bernasconi, Alessandro
AU - Dallaspezia, Sara
AU - Pagani, Elisabetta
AU - Falini, Andrea
AU - Copetti, Massimiliano
AU - Colombo, Cristina
AU - Comi, Giancarlo
AU - Smeraldi, Enrico
AU - Filippi, Massimo
PY - 2011/6
Y1 - 2011/6
N2 - Objectives: A growing body of evidence suggests that, independent of localized brain lesions, mood disorders can be associated with dysfunction of brain networks involved in the modulation of emotional and cognitive behavior. We used diffusion tensor (DT) tractography to quantify the presence and extent of structural injury to the connections between the amygdala and other brain regions, which included the subgenual, the supragenual and posterior cingulate, the parahippocampal, the orbitofrontal and dorsolateral prefrontal cortices, as well as the insula. Methods: Using a 3.0 Tesla scanner, conventional and DT magnetic resonance imaging sequences of the brain were acquired from 15 adult patients with major depressive disorder (MDD), 15 with bipolar disorder (BD), and 21 age-matched healthy controls. Using FSL software, diffusivity changes of the white matter (WM) fiber bundles belonging to the emotional network were measured. Results: Compared to controls and MDD patients, BD patients had significantly decreased average fractional anisotropy, increased average mean diffusivity, and increased average axial and radial diffusivity values in the majority of the WM fiber bundles connecting structures of the anterior limbic network (p-values ranging from 0.002 to 0.040). Medication load did not influence the results with the exception of lithium, which was associated with normal diffusivity values in tracts connecting the amygdala with the subgenual cingulate cortex. Conclusions: We detected specific WM abnormalities, suggestive of disrupted integrity of fiber bundles in the brains of patients with BD. These abnormalities might contribute to understanding both mood dysregulation and cognitive disturbances in BD, and might provide an objective marker to monitor treatment efficacy in this condition.
AB - Objectives: A growing body of evidence suggests that, independent of localized brain lesions, mood disorders can be associated with dysfunction of brain networks involved in the modulation of emotional and cognitive behavior. We used diffusion tensor (DT) tractography to quantify the presence and extent of structural injury to the connections between the amygdala and other brain regions, which included the subgenual, the supragenual and posterior cingulate, the parahippocampal, the orbitofrontal and dorsolateral prefrontal cortices, as well as the insula. Methods: Using a 3.0 Tesla scanner, conventional and DT magnetic resonance imaging sequences of the brain were acquired from 15 adult patients with major depressive disorder (MDD), 15 with bipolar disorder (BD), and 21 age-matched healthy controls. Using FSL software, diffusivity changes of the white matter (WM) fiber bundles belonging to the emotional network were measured. Results: Compared to controls and MDD patients, BD patients had significantly decreased average fractional anisotropy, increased average mean diffusivity, and increased average axial and radial diffusivity values in the majority of the WM fiber bundles connecting structures of the anterior limbic network (p-values ranging from 0.002 to 0.040). Medication load did not influence the results with the exception of lithium, which was associated with normal diffusivity values in tracts connecting the amygdala with the subgenual cingulate cortex. Conclusions: We detected specific WM abnormalities, suggestive of disrupted integrity of fiber bundles in the brains of patients with BD. These abnormalities might contribute to understanding both mood dysregulation and cognitive disturbances in BD, and might provide an objective marker to monitor treatment efficacy in this condition.
KW - Amygdala
KW - Bipolar disorder
KW - Cingulate
KW - Diffusion tensor imaging
KW - Fractional anisotropy
KW - Major depression
KW - Tractography
KW - White matter
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U2 - 10.1111/j.1399-5618.2011.00938.x
DO - 10.1111/j.1399-5618.2011.00938.x
M3 - Article
C2 - 21843281
AN - SCOPUS:80051639820
SN - 1398-5647
VL - 13
SP - 414
EP - 424
JO - Bipolar Disorders
JF - Bipolar Disorders
IS - 4
ER -