Cerebral ventricular size in depressed subjects

Volume enlargement of the choroid plexus and brain ventricles in drug-naïve, first-episode major depressive disorder

BACKGROUND

We investigated volumetric alterations in the bilateral choroid plexus (ChP) and brain ventricles of patients during their first episode of major depressive disorder (MDD) prior to antidepressant treatment.

METHODS

Seventy-one first-episode drug-naïve patients with MDD and seventy-four healthy control (HC) subjects were recruited. MRI data were obtained, and bilateral ChP and brain ventricle volumes were evaluated using segmentation, based on the adaptive multiscale and expectation maximization method. One-way multivariate analysis of covariance was used to calculate volumetric differences in the bilateral ChP and brain ventricles between the groups, and partial Pearson correlation analyses were used to investigate the relationship between the volumes of the bilateral ChP and brain ventricles.

RESULTS

First-episode drug-naïve patients with MDD showed enlarged volumes of the bilateral ChP, bilateral lateral ventricle (LV), and third ventricle compared with HCs. The ChP volume positively correlated with the LV and third ventricle, but not with the fourth ventricle in patients with MDD, whereas it correlated with all four brain ventricles in HCs. We did not observe significant correlations between bilateral ChP volume and brain ventricles, HAMD scores, or symptom severity.

LIMITATIONS

Our study populations differed in age and sex and we did not extensively measure the amount of neuroinflammation in the brain or blood, include a functional assessment, nor evaluate other neural comorbidities or neuropsychiatric conditions.

CONCLUSIONS

Our study extends the existing research to suggest that illness-related alterations in ChP volume enlargement in first-episode antidepressant-naïve patients with MDD may serve as a trait measure.

Brain Structural Effects of Antidepressant Treatment in Major Depression

Depressive disorder is a very frequent and heterogeneous syndrome. Structural imaging techniques offer a useful tool in the comprehension of neurobiological alterations that concern depressive disorder. Altered brain structures in depressive disorder have been particularly located in the prefrontal cortex (medial prefrontal cortex and orbitofrontal cortex, OFC) and medial temporal cortex areas (hippocampus). These brain areas belong to a structural and functional network related to cognitive and emotional processes putatively implicated in depressive symptoms. These volumetric alterations may also represent biological predictors of response to pharmacological treatment. In this context, major findings of magnetic resonance (MR) imaging, in relation to treatment response in depressive disorder, will here be presented and discussed.

Age-specific characteristics and coupling of cerebral arterial inflow and cerebrospinal fluid dynamics

The objective of this work is to quantify age-related differences in the characteristics and coupling of cerebral arterial inflow and cerebrospinal fluid (CSF) dynamics. To this end, 3T phase-contrast magnetic resonance imaging blood and CSF flow data of eleven young ( years) and eleven elderly subjects ( years) with a comparable sex-ratio were acquired. Flow waveforms and their frequency composition, transfer functions from blood to CSF flows and cross-correlations were analyzed. The magnitudes of the frequency components of CSF flow in the aqueduct differ significantly between the two age groups, as do the frequency components of the cervical spinal CSF and the arterial flows. The males' aqueductal CSF stroke volumes and average flow rates are significantly higher than those of the females. Transfer functions and cross-correlations between arterial blood and CSF flow reveal significant age-dependence of phase-shift between these, as do the waveforms of arterial blood, as well as cervical-spinal and aqueductal CSF flows. These findings accentuate the need for age- and sex-matched control groups for the evaluation of cerebral pathologies such as hydrocephalus.

Les anomalies structurales observées en imagerie cérébrale dans le trouble bipolaire

The number of structural neuroimaging studies of bipolar disorder have increased during recent years, expanding the literature on the nature of cerebral abnormalities underlying this disorder. The purpose of this paper is to provide a selective review on the main issues concerning this literature. Consistent findings are higher rate of periventricular and deep subcortical white matter hyperintensites seen on MRI. Although there is strong evidence for links between hyper-intense lesions and age or cardio-vascular risk factors, some authors have observed the presence of these abnormalities early in the course of the illness. There are also frequent reports on ventricular enlargement, which has been described as mild and predominant in the right lateral ventricle. Total cerebral volume appears to be preserved. Whereas changes in total grey matter volume are uncertain, evidence suggests that reduced white matter volume reflects genetic factors predisposing to the disorder. Recent studies have reported volume changes in several cortical areas including the subgenual cingular, frontal and temporal cortices. Additionally, a number of reports described morphometric abnormalities in various subcortical structures, such as amygdala, basal ganglia and thalamus. Part of the variability in the morphometric abnormalities might be attributable to differences in clinical status and demographic characteristics of patient groups. Despite some inconsistencies across the studies, it emerges that abnormalities are asymmetrically distributed throughout the two cerebral hemispheres. When increase in volume is reported, it is preferentially localised in the left cerebral hemi-sphere and more specifically in prefrontal and temporal cortices and in amygdala. By contrast, when structural abnormalities concern the right cerebral hemisphere, they are identified as deficits. These latter results are in direct line with those of studies of mania following brain injuries, which report that these secondary mania result mainly from right cerebral lesions. It is also important to notice that most of the abnormalities concern both the cortical and subcortical level, ie frontal, striatal, thalamic and limbic regions. These abnormalities highlight the role in the pathophysiology of bipolar disorder of the loops involved in emotional information processing. The particular role of fronto-limbic loops in the phenomenology of bipolar disorder have been emphasised by recent data from functional neuroimaging studies.

Volumetric brain imaging findings in mood disorders

Volumetric neuroimaging is increasingly being used by researchers of affective disorders to assess potential involvement of different brain structures in mood regulation and to test neuroanatomic models of mood disorders. In unipolar depression, findings suggest abnormalities in the frontal lobe (particularly the subgenual prefrontal cortex), basal ganglia (particularly the caudate and putamen), cerebellum, and hippocampus/amygdala complex. In bipolar disorder, abnormalities in the third ventricle, frontal lobe, cerebellum, and possibly the temporal lobe are noted. We review the findings for the various regions of the brain, and discuss the implications on the understanding of mood disorders. Directions for future research in volumetric imaging is then discussed.

Anatomical MRI findings in mood and anxiety disorders

OBJECTIVE

In vivo structural magnetic resonance imaging (MRI) studies have evaluated the brain anatomy of various psychiatric disorders, allowing the investigation of putative abnormal brain circuits possibly involved in the patophysiology of psychiatric disorders. Here we reviewed the structural MRI literature in mood and anxiety disorders.

METHODS

All anatomical MRI studies evaluating mood and anxiety disorder patients were identified through a comprehensive Medline search conducted for the period from 1966 to January 2002, and a manual search of bibliographic cross-referencing complemented the Medline search.

RESULTS

Differential patterns of anatomical brain abnormalities appear to be involved in subtypes of mood disorders, with hippocampus and basal ganglia being abnormal in unipolar disorder, and amygdala and cerebellum in bipolar disorders, suggesting that these two mood disorders are biologically distinct. As for anxiety disorders, orbital frontal regions and basal ganglia have been reported to be anatomically abnormal in obsessive-compulsive disorder, temporal lobe was found to be abnormally reduced in panic disorder, and abnormal hippocampus shrinkage was shown in posttraumatic stress disorder.

CONCLUSIONS

The structural MRI findings reviewed here suggest abnormalities in specific brain regions participating in proposed neuroanatomic models possibly involved in the pathophysiology of mood disorders and anxiety disorders. Nonetheless, available MRI studies have suffered from limitations related to relatively small patient samples and involvement of medicated patients, and were largely cross-sectional investigations. Therefore, longitudinal MRI studies involving more sizeable samples of drug-free patients, patients at first episode of illness or at high risk for mood or anxiety disorders, associated to genetic studies, are likely to be extremely valuable to separate state from trait brain abnormalities and to characterize further the pathophysiology of these disorders.

The neuropsychology and neuroanatomy of bipolar affective disorder: a critical review

Bearden CE, Hoffman KM, Cannon TD. The neuropsychology and neuroanatomy of bipolar affective disorder: a critical review. Bipolar Disord 2001: 3: 106 150. C Munksgaard, 2001

OBJECTIVES

To present a comprehensive review of the existing neuropsychological and neuroimaging literature on bipolar affective disorder. This review critically evaluates two common conceptions regarding the neuropsychology of bipolar disorder: 1) that, in contrast to schizophrenia, bipolar affective disorder is not associated with general cognitive impairment independent of illness episodes, and 2) relative right hemisphere (RH) dysfunction is implicated in bipolar illness patients, supported by reports of relatively greater impairment in visuospatial functioning, lateralization abnormalities, and mania secondary to RH lesions.

METHODS

The major computerized databases (Medline and PSYCInfo) were consulted in order to conduct a comprehensive, integrated review of the literature on the neuropsychology and neuroanatomy of bipolar disorder. Articles meeting specified criteria were included in this review.

RESULTS

In a critical evaluation of the above notions, this paper determines that: 1) while there is little evidence for selective RH dysfunction, significant cognitive impairment may be present in bipolar illness, particularly in a subgroup of chronic, elderly or multiple-episode patients, suggesting a possible toxic disease process, and 2) the underlying functional correlate of these cognitive deficits may be white matter lesions ('signal hyperintensities') in the frontal lobes and basal ganglia, regions critical for executive function, attention, speeded information processing, learning and memory, and affect regulation. While this hypothesized neural correlate of cognitive impairment in bipolar disorder is speculative, preliminary functional neuroimaging evidence supports the notion of frontal and subcortical hypometabolism in bipolar illness.

CONCLUSIONS

The etiology of the structural brain abnormalities commonly seen in bipolar illness, and their corresponding functional deficits, remains unknown. It is possible that neurodevelopmental anomalies may play a role, and it remains to be determined whether there is also some pathophysiological progression that occurs with repeated illness episodes. More research is needed on first-episode patients, relatives of bipolar probands, and within prospective longitudinal paradigms in order to isolate disease-specific impairments and genetic markers of neurocognitive function in bipolar disorder.

Regional cerebral volume measurements in late-life depression: relationship to clinical correlates, neuropsychological impairment and response to treatment

BACKGROUND

Elderly people who develop depression have demonstrable changes in cerebral structure but little is known of the relationship between regional cerebral volumes, treatment response and cognitive impairment.

METHOD

Forty-four patients with major depression diagnosed according to DSM-IIIR criteria underwent magnetic resonance imaging and regional cerebral volumes were quantified using multispectral analysis. Response to antidepressant treatment was assessed prospectively and a neuropsychological test battery was administered.

RESULTS

There was a trend for smaller fronto-temporal volumes in the treatment-resistant patients. Impaired immediate working memory was linked with reduced frontal and parietal lobe volume and impaired short-term memory functioning was associated with reduced temporal lobe volume. Ventricular enlargement was associated with prior administration of electro-convulsive therapy, poor physical health and later age at onset of first episode of depression.

CONCLUSION

In late-life depression, brain changes should not preclude vigorous antidepressant treatment. Regional cerebral volume changes may be a complication of poor physical health and are associated with memory dysfunction even upon recovery from depression.

The role of toxins in disorders of mood and affect

This article deals with disorders of mood and the interaction between mood and cognitive function. The various ways in which environmental toxins can lead to disorders of mood are presented, and discussions regarding the neurobiology of mood are presented.

Precursors to schizophrenia: do biological markers have specificity?

This review addresses childhood antecedents and biological markers of schizophrenia within a neurodevelopmental framework. General-population birth-cohort studies illustrate delays in developmental milestones, abnormalities in social functioning, and cognitive deficits throughout childhood, adolescence, and early adulthood. Abnormal neurology and motor dysfunction have been measured in children prior to the onset of schizophrenia, at first onset of disease, and in those with chronic schizophrenia. Minor physical anomalies, a static marker of developmental disturbance, are also increased in schizophrenia. None of these factors has high specificity for this disorder. This review examines the associations between these precursors and some etiological factors for schizophrenia, comments on their lack of complete specificity to this psychotic syndrome, and considers their usefulness as predictors of risk.

Depression in schizophrenia: II. MRI and PET findings

BACKGROUND

Despite consistent descriptions of depressive symptoms in schizophrenia, little is known about their neurobiology. The purpose of this study was to examine the association of depression in schizophrenia with measures of brain anatomy and metabolism.

METHODS

Seventy-nine patients were grouped according to their ratings on the Hamilton Depression Rating Scale (HDRS): > or = 18 was the cutoff between the "high" and "low" depression groups. All patients underwent clinical and magnetic resonance imaging (MRI) evaluation, and a subsample of 37 underwent 2-fluoro-2-deoxy-D-glucose-positron emission tomography (FDG-PET) measurements of cerebral glucose metabolism.

RESULTS

The high depression group had larger bilateral temporal lobe volumes and decreased laterality (left minus right of metabolism in the anterior cingulate).

CONCLUSIONS

The neurobiology of depression in schizophrenia thus seems to share features with major depression due to other disease states.

The association between Apo E genotype and depressive symptoms in elderly African-American subjects

In this study of 138 elderly subjects (112 without and 26 with dementia) obtained from a community sample of elderly African-American subjects, there were no significant differences in mean Geriatric Depression Scale scores by Apo E epsilon 4 status for dementia or nondementia subjects. Three subjects received a diagnosis of major depressive disorder. None of these subjects were Apo E epsilon 4-positive. These results do not support an association between depressive symptoms and Apo E allele status in this elderly African-American population.

Temporal lobe abnormalities in dementia and depression: a study using high resolution single photon emission tomography and magnetic resonance imaging

OBJECTIVES

Perfusion SPECT and MRI were used to test the hypothesis that late onset depression is associated with brain abnormalities.

METHODS

Forty depressed patients (DSM-III-R major depressive episode, not demented at two year follow up) were recruited who were either drug free, or on a stable dose of antidepressants for at least three weeks, as well as 22 demented patients (DSM-IIIR and NINCDS/ADRDA criteria for probable Alzheimer's disease). Patients were imaged at rest with a high resolution single slice 12 detector head scanner (SME-Neuro 900) and the cerebral perfusion marker 99mTc-exametazime (HM-PAO). Temporal lobe templates were fitted with brains pitched by 20 degrees-30 degrees. A subgroup of 41 patients (22 depressed) were also scanned using a Siemens Magnetron 1.0 Tesla magnetic resonance imager, using a FLAIR imaging sequence for the assessment of white matter hyperintensities, and a Turbo FLASH sequence for the measurement of medial temporal lobe width.

RESULTS

Demented patients showed reduced perfusion, particularly in the left temporoparietal cortex. In these regions of interest, patients with late onset depression tended to have perfusion values intermediate between patients with early onset depression and demented patients. Differences in changes in white matter between demented and early and late onset depressive patients did not reach conventional levels of significance. Temporal lobe width differed between demented and depressed patients, but not between early and late onset depressed patients. Perfusion and temporal lobe width were not associated, but reductions of perfusion were associated with periventricular white matter changes. Mini mental state examination scores were associated with temporal perfusion in demented patients and with changes in deep white matter in depressed patients. Finally, severity of depressive symptoms was associated with decreased perfusion in frontotemporal and basal ganglia regions of interest.

CONCLUSION

A cumulative effect of duration of illness on regional cerebral perfusion could not be confirmed. Late onset depression may show more abnormalities of deep white matter and of left temporoparietal perfusion than early onset depression, but the underlying pathology remains to be established.

Comparative studies of the biological distinction between unipolar and bipolar depressions

Although unipolar depression and bipolar depression are considered distinct entities both by clinicians and researchers, it is not clear whether a pathophysiological distinction, which is the bridge between etiology and treatment, exists between these two conditions. The objective of this paper was to systematically review the studies that examined the biological differences between unipolar and bipolar depression. Using computerized Medline and manual searches, we located and reviewed studies that directly compared patients with unipolar depression with bipolar depressed patients on at least one biological variable. The results showed that patients with bipolar depression had lower levels of urinary NE and its metabolites and lower platelet MAO activity, and higher platelet free and stimulated intracellular calcium levels compared with unipolar depressed patients, but none of the variables examined appeared to differentiate the two groups consistently. We discuss some of the methodological flaws that might have contributed to this, and suggest that further studies should control for such confounding variables.

Changes in CSF spaces differ in endogenous and neurotic depression. A planimetric CT scan study

Regional planimetric measurements of internal and external CSF spaces were performed in CT scans of 23 patients with endogenous depression (ICD 9, 296.1) and 28 patients with neurotic depression (ICD 9, 300.4) as compared to 56 control individuals without neuropsychiatric disorder. In female patients with endogenous depression, but not in men, the bilateral upper cortical sulci were widened, especially in the frontal regions, and the third ventricle was enlarged. In contrast, the female neurotic depressed group showed no enlargement of CSF spaces, but a narrowing of the Sylvian fissure and of the basal frontal lobe reaching level of significance in the right fronto-temporal region (P = 0.005). No narrowing of CSF spaces was observed in women with endogenous depression. A discriminant analysis of significantly changed CSF regions resulted in a correct classification in 82.4% of depressed women in either the endogenous or the neurotic group. Determination of divergent types of brain pathology might prove as a useful tool in validating the differential classification of these two main subtypes of affective disorders.

MRI findings in patients with affective disorder: a meta-analysis

A review of the literature on primarily magnetic resonance imaging (MRI) scans of patients with affective disorders is presented. Several studies have indicated an increased ventricle/brain ratio and other signs of cerebral atrophy, as well as an increased frequency of lesions (so-called signal hyperintensities) in the brains of unipolar and bipolar patients. This notion is strongly supported by two meta-analyses performed in the present study. The lesions are often localized in the frontal lobes and the basal ganglia, indicating a defective basal ganglia/frontal circuit, and are correlated with the degree of cognitive impairment seen in these conditions. No studies have indicated that psychoactive drugs or electroconvulsive therapy (ECT) might cause the lesions, but on the other hand they can probably increase the risk of delirium complicating the treatment.

Quantitative magnetic resonance imaging in geriatric depression and primary degenerative dementia

Quantitative magnetic resonance imaging (MRI) was used to investigate volumes of different brain structures in 19 patients with late-onset major depression (DSM-III-R), 27 patients with Alzheimer's disease (NINCDS-ADRDA criteria) and 13 age matched controls. 3-D MRI sequences were acquired using a Siemens 1.5 T scanner. Whole brain volume, CSF volume, volume of the frontal and temporal lobes and the volume of the amygdala-hippocampus complex were assessed using the software NMR Win. Compared to the controls, depressed patients showed a significantly lower whole brain volume and a significantly higher CSF volume, whereas volumes of the frontal and temporal lobes as well as the amygdala-hippocampus complex volumes were not significantly decreased. In addition, depressed patients exhibited a higher ventricle-brain ratio suggesting a higher degree of central atrophy compared to healthy individuals. In contrast, Alzheimer patients showed significantly lower volumes than depressed patients and controls with respect to all volumetric parameters. Although the findings indicate the presence of brain atrophy in patients with late-onset depression, the pattern of volumetric changes in these patients differs markedly from that observed in patients with primary degenerative dementia.

Neuropsychological and neuroimaging evidence for the involvement of the frontal lobes in depression

The onset and reversibility of major depression is likely to be explained by diffuse neuromodulatory mechanisms rather than permanent abnormalities of connectivity and neurotransmission. However, the expression of mood state appears to involve fronto-striatal mechanisms. Lesions of the ventral frontal cortex give rise to profound modification of affect and behaviour not explained by effects on current intellectual function. These may represent the most extreme possible disturbances of emotional experience. Neuropsychological testing in major depression shows evidence of slowing in motor and cognitive domains with additional prominent effects on mnemonic function most marked in the elderly. Structural imaging with X-ray computed tomography or magnetic resonance imaging in older patients with major depression shows evidence of structural abnormality compared with controls. These findings are not highly localizing but they tend to confirm the role of cognitive impairment as an important age-related risk factor for major depression. Perfusion or metabolic imaging reflects both reversible changes in function and permanent loss of active neurones. The usual finding has been reductions in anterior brain structures in major depression. Hypoperfusion tends to be greatest in frontal, temporal and parietal areas and most extensive in older (male) patients; high Hamilton scores tend to be associated with reduced uptake. There have also been correlations in the cingulate cortex between increased perfusion and other aspects of the mental state. In general, reductions in frontal areas may be more likely in patients with impoverished mental states. The more prominent impairments of memory are likely to be associated with the finding of impaired temporal function or with a more diffuse failure of neuromodulation.

The anatomy of mood disorders--review of structural neuroimaging studies

The structural neuroimaging findings in mood disorders were reviewed, to evaluate evidence for a neuroanatomic model of pathophysiology, involving the prefrontal cortex, the basal ganglia, the amygdala-hippocampus complex, thalamus, and connections among these structures. Global atrophy is not consistently found. The best replicated finding is an increased rate of white matter and periventricular hyperintensities. A smaller frontal lobe, cerebellum, caudate, and putamen appear present in unipolar depression. A larger third ventricle, and smaller cerebellum and perhaps temporal lobe appear present in bipolar disorder. These localized structural changes involve regions that may be critical in the pathogenesis of mood disorders. Generalized and localized anatomic alterations may be related to age or vascular disease. The clinical and biological correlates of these changes need to be investigated to allow development of a more complete model of pathophysiology of mood disorders.

Unreliability of TRH test but not dexamethasone suppression test as a marker of depression in chronic vasculopathic patients

Thirteen vasculopathic nondepressed men, admitted to the hospital 2 weeks earlier because of stroke, 10 age- and weight-matched patients with major depression, and 10 age- and weight-matched normal controls were tested with TRH and on different occasion with the dexamethasone (DEX) suppression test (DST). Patients with stroke were tested again with TRH and DST after 1 year. All subjects were euthyroid. A blunted TSH response to TRH was observed in 77% of vasculopathic patients, 64% of depressed patients, and 27% of controls. Some depressed patients showed serum GH or cortisol increments in response to TRH. Nonsuppression to DEX was observed in 45% of depressed patients and 15% of vasculopathics but not in normal controls. These data indicate that, in contrast to cortisol nonsuppression to DEX, blunted TSH response to TRH has poor diagnostic value as a marker for depression after stroke and may merely represent the expression of neuroendocrine dysfunction associated with cerebral vasculopathy.

On the Inseparability of Mental and Physical Health in Aged Persons: Lessons From Depression and Medical Comorbidity

Recent research findings demonstrate that general medical and mental health are inseparable in older individuals. The medical consequences of depression can be summarized with the unifying hypothesis that depression interacts with medical or neurological illness to modify the course of disease and to amplify its associated effects. The medical causes of depression can be divided into specific mechanisms of certain diseases or medications and general mechanisms that may integrate effects of a number of the common chronic disorders of late life. The authors discuss two general hypotheses: One suggests that depression may be associated with subclinical cerebrovascular disease in older patients with cerebrovascular risk factors; the other suggests that depression occurring in association with various conditions may be related to cytokine-mediated "sickness behavior." The research literature makes a compelling case for the need to address psychiatric-medical comorbidity in late life as a central issue in public policy and the design of health care systems.

Brain morphology assessed by computed tomography in patients with geriatric depression, patients with degenerative dementia, and normal control subjects

To determine whether patients with geriatric depression have specific alterations in brain morphology, internal (ventricles) and external (frontal, temporal, and parieto-occipital) components of the cerebrospinal fluid (CSF) spaces were examined. Planimetric measurements of computed tomographic (CT) scans from patients with geriatric depression were compared with measurements from two age- and sex-matched control groups: normal control subjects and patients with primary degenerative dementia. Scans of 34 patients (6 men, 28 women; mean age = 70.7 years) who met DSM-III-R diagnostic criteria for major depression, 29 patients with DSM-III-R primary degenerative dementia (8 men, 21 women; mean age = 71.2 years), and 43 nonpsychiatric control subjects (10 men, 33 women; mean age = 70.8 years) were evaluated. The areas of the frontal and parieto-occipital sulci, the Sylvian fissures, and the lateral and third ventricles were measured separately for the right and left hemispheres. Compared with the control subjects, patients with geriatric depression revealed a remarkable enlargement (up to 125%) of the left Sylvian fissure on several levels and a more subtle enlargement of the ventricles, cortical sulci, and right Sylvian fissure (20-50%). The laterality index differed significantly between depressed patients and normal control subjects (but not between the demented patients and the normal control group) only for the Sylvian fissure. Demented patients showed a considerable brain atrophy that affected all CSF components (enlargement of 30-160%) but the left temporal region was less affected than in the depressed patients. Compared with the findings in geriatric depression, ventricular enlargement was significant in dementia.(ABSTRACT TRUNCATED AT 250 WORDS)

Changes in regional cerebral blood flow on recovery from depression

We have previously described focal abnormalities of regional cerebral blood flow (rCBF) in the left dorsolateral prefrontal cortex (DLPFC), anterior cingulate cortex and angular gyrus in 40 patients with major depression. We now report on the patterns of change in rCBF in a subgroup of 25 of the same patients who were rescanned following clinical remission of depression. Fifteen patients were scanned when optimally matched for drug treatment (4) or drug free on both occasions (11). The other 10 patients were fully recovered but could not be matched for drug status for clinical and ethical reasons. In a paired comparison of the same patients when ill and following recovery it was evident that remission was associated with a significant increase in rCBF in the left DLPFC and medial prefrontal cortex including anterior cingulate. Increases in rCBF in the angular gyrus were not seen when the comparison of depressed and recovered scans was matched for medication. The previously described relationship between clinical symptoms and brain perfusion in the depressed state was no longer present in the recovered state; this supports the hypothesis of state relatedness. Thus, recovery from depression is associated with increases in rCBF in the same areas in which focal decreases in rCBF are described in the depressed state in comparison with normal controls.

Effects of major depression on the cognitive function of younger and older subjects

The effects of age and depression on cognitive function were investigated in two groups of in-patient major depressives aged under and over 60 years who were tested when depressed and after recovery. The majority of the tests showed impaired performance during depression with improvement after recovery, and also differences between the two age-groups in both the depressed and recovered phases. However, the older subjects were not more severely affected by depression than the younger subjects. The pattern of impairment associated with depression was different to that associated with older age: depression affected performance on more 'complex tasks', whereas age was associated particularly with slowing on timed tests. This study did not suggest that the impairment from baseline due to the depression is greater in the elderly than in younger subjects.

Some methodological issues in neuroradiological research in psychiatry

An outline is given of some of the methodological issues discussed in neuroradiological research on psychiatric illness. Strengths and shortcomings of magnetic resonance imaging (MRI) in depicting and quantifying brain structures are described. Temporal lobe anatomy and pathology are easily accessible to MRI, whereas limits on anatomical delineation hamper approaches to frontal lobe study. White matter hyperintense lesions are sensitively depicted by MRI, but specificity is limited. Distinction of vascular and primary degenerative dementia is considerably improved by CT and MRI analysis. Computed tomography (CT) and MRI have enhanced the understanding of treatable organic psychiatric disorders, e.g., normal pressure hydrocephalus. Subcortical and white matter pathology has been replicated in CT and MRI studies of late-onset psychiatric disorders, clinical overlap with cerebrovascular disease or neurodegeneration may be of import. Transcranial sonography findings of brainstem structural change specific to unipolar depression may contribute to the understanding of affective psychoses. Magnetic resonance spectroscopy and functional MRI are likely to stimulate psychiatric research in the future.

Cerebral ventricle dimensions as risk factors for schizophrenia and affective psychosis: an epidemiological approach to analysis

A case-control study was undertaken of volumetric computerized tomographic scan measures in 216 consecutive admissions for functional psychosis and 67 healthy community controls. Odds ratio analysis demonstrated significant linear trends in the association between increasing lateral and third ventricle volumes, and both RDC schizophrenia (N = 121) and schizo-affective disorder (N = 41); cases were consistently associated with larger volumes than controls. There was an association between larger third, but not lateral, ventricle size in affective psychoses (N = 54). These associations were statistically independent of intracranial volume, sex, social class and ethnicity, factors which were significantly associated with ventricular measures in the controls. There was no evidence of a threshold corresponding to the notion of normal versus enlarged ventricles. Within the schizophrenia group, there were no large or significant associations between ventricle dimensions and age at onset, duration of illness or pre-morbid social functioning. Neither obstetric complications nor a family history of schizophrenia or other psychiatric illness was associated with large ventricles in these cases.

Uptake of 99mTc-exametazime shown by single photon emission computerized tomography in obsessive-compulsive disorder compared with major depression and normal controls

Twelve patients with obsessive-compulsive disorder (OCD) were investigated at rest using single photon emission computerized tomography with 99mTc-exametazime. The uptake of 99mTc-exametazime was expressed relative to calcarine/occipital cortex. Patients were matched for drug treatment with 12 patients with a major depressive episode and the patient groups were compared with a control group. Significant bilateral decreases in tracer uptake were confined to basal ganglia in the OCD group. There was a paradoxical positive correlation between anxiety ratings and tracer uptake to basal ganglia in the OCD group. The findings confirm that the functional topography of OCD implicates altered function in the basal ganglia.

State changes in brain activity shown by the uptake of 99mTc-exametazime with single photon emission tomography in major depression before and after treatment

Twenty-eight patients with a major depressive episode previously investigated at rest using Single Photon Emission Tomography (SPET or SPECT) with 99mTc-exametazime, were followed up at an interval of 9-28 months with the same investigation after full recovery. All patients were unipolar and were rated on the Newcastle scale and with the 17-item Hamilton scale. The uptake of 99mTc-Exametazime was expressed relative to calcarine/occipital cortex. Sixteen patients were scanned when optimally matched for drug treatment (4) or on both occasions drug free (12). The other 12 patients were fully recovered but could not be matched for drug status; these patients showed significantly more retardation, diurnal mood variation and guilt at presentation. Significant bilateral increases in tracer uptake were confined to basal ganglia and inferior anterior cingulate cortex in the matched group, where there were additional increases in thalamus and posterior cingulate cortex on the right side. There were no statistically discernible changes in the neocortex in the matched sample. The unmatched sample yielded inconclusive evidence of increased tracer uptake in left temporal cortex. The findings give a potential focus to the neuropharmacological analysis of depressive illness because the topography of the state change in brain function implicates dopamine function.

Computed axial brain tomograms in long-term benzodiazepine users

Computed axial brain tomograms were recorded in four groups of subjects: (a) subjects who had never taken benzodiazepines (n = 25); (b) subjects who had taken them in the past for less than a year (n = 9); (c) patients currently taking benzodiazepines (n = 30); and (d) patients who had taken benzodiazepines in the past for at least a year and who had been withdrawn from medication for at least 6 months (n = 17). Ventricle-to-brain ratios and tissue absorption to X-rays were computed. No overall differences were found between the main groups. However, a few brain regions differed in density between nonusers and heavy users, particularly those taking lorazepam.

A single photon emission computerised tomography study of regional brain function in elderly patients with major depression and with Alzheimer-type dementia

The uptake, at rest, of 99mTc-exametazime into different brain regions was compared using SPECT for 20 elderly subjects with major depressive disorder, 20 with Alzheimer-type dementia, and 30 age-matched normal volunteers. Uptake was referred to calcarine-occipital cortex as a reference sensory area. Cross-sectional differences between the three groups were highly statistically significant, but reflected primarily the reductions in cortical uptake in the Alzheimer group. A detailed comparison of depressed patients and controls identified decrements in anterior cingulate, temporal and frontal cortex and in caudate and thalamus in men only. These decrements were correlated with impairment of performance on a trail-making task, but were also associated with continuing treatment with antidepressants or benzodiazepines. However, most depressed patients had quantitatively normal scans for posterior parietal association cortex, and this suggests that SPECT may find a limited role in the differential diagnosis of depression and dementia. The reduced brain function in some depressed patients may parallel the findings from studies of brain structure in elderly depressives; there was between good outcome at 6-18 months and increased tracer uptake in subcortical areas.

Neuroanatomic substrates of depression in the elderly

The causes of depression in the elderly are poorly understood. The concept that psychological and social factors are the primary contributors to the occurrence of depression in later life, though intuitively appealing, is not supported by available evidence. In addition, genetic factors are less significant in patients presenting with depression for the first time in later life. In this article, the following hypotheses are examined: (1) the aging process facilitates emergence of depression in later life; (2) cerebrovascular pathology plays a role in the etiology of depression in the elderly; and (3) the site and location of changes in the brain provide a basis for understanding neuroanatomic substrates of depression in the elderly. The role of the basal ganglia and different basal ganglia circuits in the pathophysiology of depression is discussed. The clinical significance of the findings of structural changes in the brain are also discussed.

Single photon emission tomography with 99mTc-exametazime in major depression and the pattern of brain activity underlying the psychotic/neurotic continuum

Forty patients with a major depressive episode were investigated at rest using Single Photon Emission Tomography (SPET or SPECT) with 99mTc-exametazime, an intravenous ligand taken into brain in proportion to regional cerebral blood flow, thereby providing an estimate of regional metabolism. All patients were unipolar and were rated on the Newcastle scale and with the 17-item Hamilton scale. They also completed a range of neuropsychological tests. They were compared with 20 control subjects matched for age, gender, premorbid intelligence and education. The uptake of 99mTc-exametazime was expressed for a range of anatomically defined regions of interest relative to calcarine/occipital cortex. The depressed group showed reduced uptake in the majority of cortical and sub-cortical regions examined, most significantly in temporal, inferior frontal and parietal areas. Unexpectedly, there was a strong positive association between uptake and scores on the Newcastle scale, especially in cingulate areas and frontal cortex. After removing the variance attributable to the Newcastle ratings, however, there emerged the expected negative association between Hamilton scores and anterior tracer uptake. The associations between neuropsychological impairment and regional brain uptake of tracer in part reflected the pattern seen with the Newcastle scale: for example, impairment of memory function correlated with higher uptake into posterior cingulate areas. We propose that depressive illness may be characterised by two processes. One leads to an overall reduction in anterior neocortical function, perhaps related to symptom severity. The other mechanism is manifest as relatively increased function, most notably within cingulate and frontal areas of the cerebral cortex in association with psychotic symptoms. The findings offer new understanding of the brain states underlying depressive illness and a potential focus to subsequent neuropharmacological analysis.

The anatomy of melancholia--focal abnormalities of cerebral blood flow in major depression

Using positron emission tomography (PET) and 15Oxygen, regional cerebral blood flow (rCBF) was measured in 33 patients with primary depression, 10 of whom had an associated severe cognitive impairment, and 23 age-matched controls. PET scans from these groups were analysed on a pixel-by-pixel basis and significant differences between the groups were identified on Statistical Parametric Maps (SPMs). In the depressed group as a whole rCBF was decreased in the left anterior cingulate and the left dorsolateral prefrontal cortex (P less than 0.05 Bonferroni-corrected for multiple comparisons). Comparing patients with and without depression-related cognitive impairment, in the impaired group there were significant decreases in rCBF in the left medial frontal gyrus and increased rCBF in the cerebellar vermis (P less than 0.05 Bonferroni-corrected). Therefore an anatomical dissociation has been described between the rCBF profiles associated with depressed mood and depression-related cognitive impairment. The pre-frontal and limbic areas identified in this study constitute a distributed anatomical network that may be functionally abnormal in major depressive disorder.

Brain computed tomography findings in geriatric depression and primary degenerative dementia

Brain computed tomography (CT) scans were performed in hospitalized geriatric patients with major depression (n = 45) or primary degenerative dementia (n = 21). Depressed patients with onset of illness at age 60 years or older (n = 32) had greater ventricular size than geriatric depressives with earlier age of illness onset (n = 13). CT parameters of late-onset depressives were comparable to those of patients with primary degenerative dementia. However, early-onset geriatric depressives had significantly smaller ventricles and less sulcal widening than demented patients. The findings suggest that late-onset depression may have a stronger association with neurological dementing disorders than early-onset depression.

The psychogeriatrician's view: management of chronic disability in the community

Psychiatric services for elderly people are based on principles which are relevant to the management of chronic disorders such as Parkinson's disease. Psychological and biological factors are closely intertwined in dementia, as they are in PD. Although medical diagnosis is important the emphasis is on continuing support. The aim is to provide services within the community where they are needed, and to acknowledge the importance of carers and family for assessment and management.

Magnetic resonance in patients with affective illness

Magnetic resonance imaging is presently being utilized to understand the neuropathology of affective disorders. Present research has demonstrated brain changes in affective disorders that correlate with neuroendocrine findings and are similar to changes noted in normal aging.

All-night electroencephalographic sleep and cranial computed tomography in depression. A study of unipolar and bipolar patients

All-night electroencephalographic (EEG) sleep recording and cranial computed tomography were performed in 24 inpatients with major depression (14 unipolar, 10 bipolar). The patients showed the characteristic "depression-like" EEG sleep alterations and their ventricular brain ratio (VBR) was increased compared with the control subjects. No major differences were found between the unipolar and the bipolar groups. There was a close and positive association between the VBR values and several measures of slow wave sleep. It is hypothesized that this relationship is due to an altered function of the limbic-hypothalamic-pituitary-adrenocortical axis in depression that affects both EEG sleep and brain morphology.

Ventricular enlargement and caudate hyperdensity in elderly depressives

Twenty-five elderly patients (mean age 73 years, range 61-88 years) with major depression underwent cranial computed tomography (CT). The findings were compared with healthy age- and sex-matched controls. The radiodensity of the left and right heads of the caudate was significantly higher in the depressed patients (p less than 0.05). The third ventricle was significantly enlarged (p less than 0.05); this effect did not reach statistical significance for the lateral ventricles. Ventricle size in the patient sample increased with age, duration of illness, and number of depressive episodes. This effect was largely age-driven for the third ventricle. Enlargement of the anterior horns appeared to be primarily influenced by the combined effects of early onset and bipolarity of illness. Densitometric measurements of the grey and white matter did not show significant correlations with age, number, or frequency of depressive episodes, age of onset, or duration of illness.

Relationship of lateral ventricular size to psychophysiological measures and short-term outcome

To examine clinical and psychophysiological correlates of lateral ventricular size, computerized tomographic (CT) scans were obtained on a sample of 88 patients who had experienced their first psychotic episode. Patients met DSM-III criteria for schizophrenia, schizophreniform disorder, or affective disorder with psychotic features. For patients with schizophrenia, large lateral ventricles were associated with unfavorable outcome. No association between outcome and ventricular size was found in patients with affective or schizophreniform disorder. Patients with mood disorders who had large ventricles consumed significantly greater amounts of alcohol than those with small ventricles. No differences were found between patients with large or small ventricles in premorbid functioning, smooth pursuit eye tracking, or electrodermal activity.

Computed tomography of the brain in unipolar depression

Several authors have reported enlarged lateral brain ventricles in major depressive patients as compared to healthy controls. Also, the enlargement of brain lateral ventricles has been related to delusions, psychomotor retardation and some biochemical data such as cortisol secretion and L-tryptophan serum levels. The present study was undertaken to investigate if melancholic depressives are characterised by a higher degree of brain atrophy than normal controls and minor depressives, the origin of any brain atrophy, and whether measures of brain atrophy are related to cortisol secretion and L-tryptophan serum levels. We investigated 10 healthy controls and 35 depressive patients categorised according to DSM-III. In contrast to previous studies, we determined a combination of indices which makes it possible to differentiate between central and cortical diffuse atrophy. We found no evidence for the existence of abnormal atrophy of the brain in melancholics; nor did we find any correlation between CT scan measurements and cortisol or tryptophan.

Psychosis associated with demonstrable brain disease

Sixty-five psychotic patients with unequivocal evidence of brain pathology and a variety of neurological disorders were assessed with respect to phenomenology and outcome. No relationship was found between site of brain pathology and type of psychotic disorder. A majority of patients had a syndrome indistinguishable from schizophrenia without coarse brain involvement and shared similar variables predicting outcome of psychosis, thus raising important issues concerning their nosological status.