Brain Voxel-based Morphometry in Mania Clinical Trial
Official title:
Differences in Voxel-based Morphometry of Different Brain Structures in Patients With Mood Disorder Bipolar Mania in Comparison to Morphometry of Nrmal Controls
Bipolar disorder is a complex psychiatric disorder characterized by recurrent episodes of mania or hypomania and depression, and affects around one to three percent of the population . Bipolar Disorder is associated with significant psychosocial morbidity and mortality , and is among the leading causes of disability worldwide . The disease is highly heritable, but the underlying pathophysiology is not yet understood .
It is recognized that lesions in some specific neuro-anatomic areas due to brain disease,
e.g., stroke or brain tumor, may lead to the development of secondary depression. The
possibility of structural brain abnormalities as a cause of depression stimulated the use of
structural brain imaging studies. Developments in structural neuroimaging by computed
tomography and magnetic resonance imaging in the past 15 years facilitated the direct
examination of specific brain structures, making the study of the relationship between
anatomy and psychopathology is possible.
Neuro-anatomic model of mood regulation :
The prefrontal cortex has extensive connectivity to cortical and subcortical circuits that
may underlie its importance in cognitive functions and modulation of limbic activity .The
main subcortical structures participating in these circuits are the basal ganglia, thalamus,
hypothalamus, brainstem, and the white matter tracts that connect these structures among
themselves and to the cerebral cortex . A limbic-thalamic-cortical circuit consisting of the
amygdala, the medio-dorsal nucleus of the thalamus, and the medial and ventro-lateral
prefrontal cortex, and a limbic-striato-pallidal-thalamic circuit comprising the striatum,
the ventral pallidum, and the components of the other circuit are the main neuro-anatomic
circuits that have been proposed to participate in the pathophysiology of mood disorders.
The basal ganglia connect with cortical and limbic regions through circuits that, despite
functioning segregated, are organized in parallel , in such a way that lesions in different
parts of these circuits could result in malfunction. Additionally, the cerebellum, through
connections with the brainstem and limbic structures, may also be involved in mood
regulation.
Both primary and secondary mood disorders may involve abnormalities in specific
fronto-subcortical neuro-anatomic circuits. Abnormalities in these brain regions or in
contiguous areas that can affect the connections between these regions could reflect
malfunction of these circuits, associated with development of mood disorders. Alternatively,
abnormalities in these circuits could confer vulnerability to mood disorders, and its onset
could be determined by interactions with environmental and genetic factors. Deficits during
brain development due to these factors could result in under-development of particular brain
areas, which could be related subsequently with mood disorders. The aging process or
pathology such as vascular brain disease could result in atrophy of some of these regions.
Thus, the influence of genetic, environmental, developmental, and degenerative factors during
the development of these brain structures may determine the onset of mood disorders .
Although structural brain abnormalities in Bipolar Disorder have been reported, the pattern
of structural brain abnormalities based on magnetic resonance imaging is still not clearly
defined.
Aim of the study :
To study the morphometric criteria of different brain structures in patients with Bipolar
Disorder type I mania in comparison to healthy subjects.
Subjects and Methods:
Patients :
Inclusion criteria:
Patients diagnosed to have mood disorder Bipolar I mania with or without psychotic features
according to criteria of Diagnostic and statistical Manual of Mental disorder-IV (American
Psychiatric Association 1994) by psychiatric sheath of psychiatric unit at Assiut University
hospital .
The patients will be arranged in Two subgroups:
first group: twenty five patients in more than one episode second group: twenty age and
sex-matched healthy subjects will be enrolled in the study
.
Exclusion Criteria:
first and second degree relatives of psychiatric patients will be excluded from the healthy
controls.
Persons with any neurological disorder or other psychiatric illness will be excluded from
controls Patients with proven major structural abnormality as detected during Magnetic
resonance Imaging Examination will be excluded from patients or healthy controls.
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