Neuroimaging and the Pathophysiology and Treatment of Depression: Recent Advances and Future Needs (original) (raw)

Neuroimaging and Psychiatric disorders: a literature review

Indian Journal of Mental Health 2023; 10(2), 2024

The aim of this review is to estimate the rate of organic brain abnormalities in patients who present with psychiatric disorders. The literature overview was composed using database including Research Gate, Psyc Info, PubMed, Scopus, Science Direct, and Google Scholar to conduct a thorough search. There are a variety of neuroimaging techniques that can provide insight into the pathophysiology, and abnormalities of the brain in patients with psychiatric disorders. Computed tomography scans show mild enlargement of the ventricles and sulci, as well as reversed asymmetry of the Sylvian fissure. A Magnetic resonance imaging study generally shows grey matter reduction, primarily in the frontal and temporal limbic regions, along with gross abnormalities of the brain like deviated sulcogyral patterns. There is a reduction in fractional anisotropy and white matter in diffusion tensor imaging scan, and in positron emission tomography studies, there is a reduction in dopamine transporter density. Neuroimaging is a technique that studies the structure and function of the nervous system using imaging technology, where images of the brain are obtained noninvasively. The Psychiatric disorders are also associated with abnormalities in the nervous system so neuroimaging plays an important role in psychiatric disorders. We have discussed the importance of neuroimaging in the workup and evaluation of psychiatric disorders. This review provides physicians with primary knowledge on the neurobiology of psychosis based on a collection of in vivo brain imaging studies, as well as insight into future operations in neuroimaging.

MRI Deep white matter hyperintensity in a psychiatric population

Biological Psychiatry, 1991

The authors evaluated magnetic resonance imaging (MRI) of deep white matter hyperintensity (DWMH) in 90 adult psychiatric inpatients in whom MRls were clinically indicated and 25 age-m:ztched, medically healthy controls. Forty-two percent of the psychiatric patients and 12% of the controls had evidence of DWMH on MRI. Both incidence and severity of DWMH were sign~cantly correlated with age in both group~. Even after controlling for age in the psychiatric population, DWMH was significantly associated with hypertension, history of myocardial infarction or angina, abnormal electrocardiogram, and abnormal neurological examinations.

White matter hyperintensities in bipolar and unipolar patients with relatively mild-to-moderate illness severity

Journal of Affective Disorders, 2003

Background: Increased rates of white matter hyperintense lesions have been reported in mood disorder patients. However, the potential effects of age and illness severity on reported findings are not fully established. We examined the rates of hyperintense lesions in adult, non-elderly bipolar and unipolar patients, with a relatively mild-to-moderate illness severity, and in matched healthy controls. Method: We examined brain MRI images in 24 bipolar (19 -56 years, mean F S.D. = 34.2 F 9.9 years) and 17 unipolar patients (24 -59 years, 42.8 F 9.2 years), and 38 healthy controls (21 -59 years, 36.8 F 9.7 years). T2weighted and proton-density axial MRI images were obtained at 1.5 Tesla. The lesions were rated by two independent raters, using a semi-quantitative rating scale. Results: There were no significant differences in the frequency of hyperintensities between bipolar or unipolar patients and healthy controls. Age was related to the presence of subcortical gray matter hyperintensities for the whole sample. Among the unipolar patients, length of illness and presence of mood disorder in a firstdegree relative were related to deep and periventricular white matter lesions, respectively. Limitations: The methodology utilized for measurement of the white matter hyperintensities was semi-quantitative. Conclusions: Increased rates of white matter hyperintensities do not appear to be present in a group of relatively young mood disorder patients, with relatively mild to moderate illness severity. These brain lesions may be more directly related to late-life and more severe cases of these illnesses. D

Increased rates of white matter hyperintensities in late-onset bipolar disorder

Bipolar Disorders, 2008

Cerebral white matter hyperintensities (WMH) are foci of bright signal, detectable on T2weighted or fluid-attenuated inversion recovery (FLAIR) magnetic resonance imaging (MRI) scans, located preferably on periventricular and deep white matter areas, as well as in subcortical structures such as the basal ganglia (1, 2). These lesions are commonly seen in association with aging (3, 4) and may be related to cognitive decline (5-8). Moreover, there is strong evidence that WMH in the elderly population are related to cerebrovascular risk factors, such as hypertension and diabetes , suggesting the existence of ischemic mechanisms underlying such lesions in old age.

White matter abnormalities in depression: A categorical and phenotypic diffusion MRI study

NeuroImage: Clinical

Mood depressive disorder is one of the most disabling chronic disease with a high rate of everyday life disability that affects 350 million people around the world. Recent advances in neuroimaging have reported widespread structural abnormalities, suggesting a dysfunctional frontal-limbic circuit involved in the pathophysiological mechanisms of depression. However, a variety of different white matter regions has been implicated. These inconsistent results might be attributed to various factors: symptoms and duration of the disease as well as clinical phenotype. In this study, we examined WM integrity in a large cohort (114 patients) compared to a healthy control group. Consistent with previous studies, reduced white matter integrity was observed in the genu of the corpus callosum extending to the inferior fasciculus and posterior thalamic radiation, confirming a frontal-limbic circuit abnormality. Our analysis also reported other patterns of increased fractional anisotropy and axial diffusivity as well as decreased apparent diffusion coefficient and radial diffusivity in the splenium of the corpus callosum and posterior limb of the internal capsule. Moreover, we sought to identify specific WM alterations in relation to specific depressive phenotypes such as anhedonia (i.e. lack of pleasure), anxiety and psychomotor retardation-three core symptoms involved in depression. A positive correlation between FA and anhedonia was found in superior longitudinal fasciculus as well as a negative correlation in the cingulum. Then, the analysis of the anxiety and diffusion metric revealed that increased anxiety was associated with greater FA values in genu and splenium of corpus callosum, anterior corona radiata and posterior thalamic radiation. Finally, the motor retardation analysis showed a correlation between increased Widlöcher depressive retardation scale scores and reduced FA in the body and genu of the corpus callosum, fornix, and superior striatum. Through this twofold approach (categorical and phenotypic), this study has underlined the need to move forward to a research area of biomarkers, which help to understand the pathophysiology of mood depressive disorder and to stratify precise phenotypes of depression with targeted therapeutic strategies.

Altered white matter volumes in first-episode depression: Evidence from cross-sectional and longitudinal voxel-based analyses

Journal of Affective Disorders, 2019

Background: Major depressive disorder (MDD) is accompanied by atypical brain structure affecting grey and white matter from the early stages. Neuroimaging studies of first-episode depression (FED) have provided evidence on this regard, but most of the studies are cross-sectional. The aim of this longitudinal study was to test potential changes in grey matter (GM) and white matter (WM) volumes in FED. Methods: Thirty-three untreated FED patients (DSM-IV criteria) and 33 healthy controls (HC) underwent a 3T structural magnetic resonance imaging (sMRI) at baseline and after 2 years. Depressive symptoms were assessed at baseline and throughout the study with the 17-item Hamilton Depressive Rating Scale (HDRS-17). Recurrences of FED patients were also collected along the follow-up. To analyze GM and WM differences, wholebrain voxel-based morphometry (VBM, SPM12) was employed (FWE corrected). Results: FED patients showed significant reductions compared to HC in WM volumes of prefrontal cortex (left anterior corona radiata). No differences were found in GM volumes. Full factorial longitudinal analysis of the whole sample revealed no significant effect in GM nor in WM, while the full factorial longitudinal analysis comparing recurrent and non-recurrent patients showed increments in WM volumes of left posterior corona radiata and right posterior thalamic radiation in the recurrent group. Limitations: Limited sample size, especially in the follow-up. Conclusions: The present findings provided some new evidence of the role of white matter alterations in the early stages of MDD and in the progression of the illness.

White matter hyperintensities in subjects with bipolar disorder

Psychiatry and Clinical Neurosciences, 2004

There have been divergent reports on the prevalence and severity of white matter hyperintensities (WMH) on brain magnetic resonance (MR) images in subjects with bipolar disorder. In the present study, evaluations were made on the prevalence and severity of WMH in subjects with bipolar disorder using contiguous 3-mm thick MR slices as well as fluid attenuated inversion recovery (FLAIR) images. A detailed WMH rating system was employed to assess these WMH. A total of 43 bipolar patients, as diagnosed by the Structured Clinical Interview from the Diagnostic and Statistical Manual-IV (SCID-IV), and 39 healthy comparison subjects were scanned using a 1.5-T whole body GE magnetic resonance scanner. WMH were assessed with a modified composite version of the Fazekas' and Coffey's rating scales to detect less severe WMH. Periventricular and subcortical WMH were coded separately. Subjects with bipolar disorder had greater prevalence of WMH abnormalities than comparison subjects (Bipolar, grade 1 = 11.6%, grade 2 = 9.3%, grade 3 = 7.0%; Comparison, grade 1 = 5.1%, grade 2 = 2.6%, grade 3 = 0%). This difference is mainly due to the differences in deep WMH (Bipolar, grade 1 = 14.0%, grade 2 = 14.0%; Comparison, grade 1 = 7.7%, grade 2 = 0%). The current study confirms the higher prevalence of WMH in subjects with bipolar disorder. Differences of small-sized WMH abnormalities between groups were successfully detected using a large number of bipolar subjects and thinner sliced MR images with FLAIR.