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Query: UMLS:C0036341 (schizophrenia)
 60,220 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Brain imaging has become an integral part of the evaluation of neurological and psychiatric disorders. Functional imaging techniques, SPECT and PET, together with structural modalities, CT and MRI, are widely employed. Functional imaging studies are routinely used in the diagnostic workup of patients with well-characterized neurological disorders, such as epilepsy and brain tumors, and have a growing role in research on psychiatric disorders without known mechanisms such as depression and schizophrenia. Furthermore, many well-defined neurological disorders manifest prominent psychiatric symptomatology which may pose difficulties in differential diagnosis. This review addresses the current knowledge of SPECT findings in patients who present with psychiatric phenomena, associated with disorders at the interface of neurology and psychiatry.
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PMID:Brain SPECT imaging of neuropsychiatric disorders. 877 8

Much of the literature shows various regional structural brain abnormalities in schizophrenia, but the complexity and variability of brain makes it difficult to determine how these regions are related. Statistical methods which estimate factors underlying patterns of covariance have not been widely used, but could be useful for analyzing such complex data. We applied exploratory and confirmatory factor analysis procedures to specific cortical and subcortical regional brain volume measures from MRI data in 60 normal and 44 schizophrenic subjects. Basal ganglia, heteromodal cortical gray, and medial temporal lobe factors were present in both the normal and the schizophrenia groups. The factor structure observed in the normal group showed a high degree of bilateral symmetry which is present but disrupted in the schizophrenia group. In the bilateral data, the disruption is most pronounced with medial and lateral temporal lobe structures including entorhinal cortex and anterior and posterior superior temporal gyri. There was a significant correlation between the basal ganglia factor and the heteromodal cortical gray factor in the normal group that was not present in the schizophrenia group. In the unilateral data, left posterior superior temporal gyrus did not load onto any factor in the schizophrenia group. Confirmatory factor analyses showed significant differences between the two groups in factor structure. A number of specific brain regions are affected in schizophrenia, and structural relationships between groups of regions also are abnormal. The results suggest that heteromodal dorsolateral prefrontal and superior temporal cortical gray regions are structurally related, whereas inferior parietal cortical gray is less so. These results should be viewed as preliminary as the ratio of parameters to subjects was relatively low, and replication is needed. However, the results demonstrate the potential utility of latent structure methods such as factor analysis in study of complex relationships in neuropsychiatric data.
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PMID:Exploratory factor analysis of MRI brain structure measures in schizophrenia. 878 7

Ventricular enlargement has been consistently demonstrated in schizophrenia using both CT and MRI. Despite this, the structural changes that underlie increased ventricle-brain ratio (VBR) and its relationship to environmental factors (intrauterine viral exposure, obstetric complications, etc.) and family history of schizophrenia remain poorly defined. Increased VBR has been shown in some studies to correlate with an absence of family history of schizophrenia and with Winter-Spring birth. In an attempt to obtain a clearer picture of the contribution of environmental and genetic factors to VBR, we studied 54 patients with DSM III-R schizophrenia. VBR was determined from head CT scans via computerized planimetry. Family history of psychosis and non-psychotic mood disorder was determined with the family informant method. Season of birth was encoded in several ways, including season, trimester and dichotomously. Patients without a family history of psychosis had significantly larger VBR than patients with such a history; family history of mood disorder was not related to VBR. Season of birth was not predictive of VBR. Family history of psychosis and season of birth were not related to each other. These results are in line with prior work demonstrating an association between increased VBR and sporadic (non-familial) schizophrenia. We did not find a relationship between VBR and season of birth, which suggests that risk of perinatal viral exposure and other seasonal environmental factors may not account for the ventricular enlargement in non-familial schizophrenia observed in our sample.
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PMID:VBR in schizophrenia: relationship to family history of psychosis and season of birth. 882 54

It is well established that many schizophrenia patients manifest behavioral dysfunction long before the onset of clinical symptoms of illness. Some show signs of motor and socioemotional deficit as early as infancy. The present study examines the relations among childhood neuromotor, affective and behavior characteristics, and the association of these factors with adult brain morphology (MRI) in schizophrenia patients. Data on neuromotor functions and negative affect were obtained from coding of childhood films. Parents of patients provided information about six dimensions of childhood behavior problems. Analyses of data from patients and healthy siblings revealed that childhood neuromotor abnormalities and negative affect were associated with some of the behavioral dimensions. Among the patients, early childhood neuromotor deficits and negative affect were linked with greater ventricular enlargement in adulthood. The ratings of the behavior problem dimensions showed a complex relation with adult brain morphology, suggesting that externalized problems are linked with more abnormalities (smaller brain volume and larger ventricles), whereas internalized problems are associated with less abnormality. The findings are discussed in light of their implications for the developmental origins of brain abnormalities in schizophrenia.
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PMID:Childhood behavioral characteristics and adult brain morphology in schizophrenia. 895 92

We reviewed 7 cases with posterior fossa structural abnormalities (3 tumors, 2 megacisterna magna and 2 Dandy-Walker syndrome) presenting with neuropsychiatric symptomatology. Derangement in the balance of dopamine, serotonin and noradrenergic networks has been implicated in the pathogenesis of schizophrenia, affective and even personality disorders. Disruption of the cerebellar output to mesial dopaminergic areas, locus coeruleus and raphe nuclei, or deafferentation of the thalamolimbic circuits by a cerebellar lesion may lead to behavioral changes. Seven patients (pts) (comprising 4 men and 3 women with mean age 22 years) were diagnosed as suffering from psychosis (2 pts), major depression (1 pt), personality disorders (2 pts) and somatoform disorders (2 pts) (DSM-IV criteria). Brain CT scan (7 pts) and MRI (4 pts) revealed tumors of the posterior fossa (2 pts), megacisterna magna (2 pts) and Dandy-Walker variant (2 pts). In one patient a IVth ventricle tumor was removed in childhood.
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PMID:Posterior fossa lesions associated with neuropsychiatric symptomatology. 900 73

The authors examined the reports of MRI brain studies of 69 patients with DSM-III-R-diagnosed psychotic disorders (30 early-onset and 24 late-onset schizophrenia patients and 15 with other psychoses) and 41 normal comparison subjects. Participants' ages ranged from 45 to 87 years. A qualitative rating scheme determined type and severity of clinically detectable abnormalities, including volume loss, infarcts, lacunae, and white matter hyperintensities. In this clinically well-characterized sample, the vast majority of the MRIs were within normal limits. There were no significant differences between psychosis patients and normal comparison subjects or between early-onset and late-onset schizophrenia patients in frequency, type, or severity of gross structural abnormalities. The results indicate that late-onset schizophrenia and related disorders can exist without clinically significant gross structural abnormalities in the brain.
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PMID:Lack of clinically significant gross structural abnormalities in MRIs of older patients with schizophrenia and related psychoses. 914 5

Patients with schizophrenia have larger lateral ventricles, less cerebral substance and smaller mesial temporal lobe structures than groups of normal controls, but it has proved difficult to link these volumetric abnormalities with clinical features of the illness. Such quantitative techniques may overlook qualitative abnormalities of importance. We therefore compared a neuroradiologists' clinical assessment of gross structural abnormalities, generalised 'atrophy' and high intensity signal (HIS) foci, as detected on the first and second echo of a long TR sequence, in 42 patients with schizophrenia (22 treatment responsive, 20 treatment resistant) and 50 normal controls. The schizophrenic group included two (5%) subjects with gross lesions, two (5%) with cerebellar atrophy, 21 (52%) with at least a mild degree of cerebral atrophy, and 15 (38%) with one or more HIS foci; the comparable figures in the controls being 2, 0, 2 and 14%, respectively. Controlling for age, patients with schizophrenia had a substantially elevated rate of cerebral atrophy (odds ratio (OR) = 11.7, p < 0.0001). Treatment-resistant schizophrenics showed a tendency (OR = 2.8, p = 0.06) to greater atrophy than those who were treatment responsive, whereas our previous volumetric study showed no such difference. In contrast, the presence of HIS foci was only related to age. The degree of atrophy was correlated with the number of HIS foci (r = 0.31, p = 0.014). Taken together with previous studies, these findings demonstrate the value of qualitative examination of MRI images in patients with schizophrenia.
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PMID:Qualitative cerebral morphology in schizophrenia: a magnetic resonance imaging study and systematic literature review. 918 15

An automated registration algorithm was used to elastically match an anatomical magnetic resonance (MR) atlas onto individual brain MR images. Our goal was to evaluate the accuracy of this procedure for measuring the volume of MRI brain structures. We applied two successive algorithms to a series of 28 MR brain images, from 14 schizophrenia patients and 14 normal controls. First, we used an automated segmentation program to differentiate between white matter, cortical and subcortical gray matter, and cerebrospinal fluid. Next, we elastically deformed the atlas segmentation to fit the subject's brain, by matching the white matter and subcortical gray matter surfaces. To assess the accuracy of these measurements, we compared, on all 28 images, 11 brain structures, measured with elastic matching, with the same structures traced manually on MRI scans. The similarity between the measurements (the relative difference between the manual and the automated volume) was 97% for whole white matter, 92% for whole gray matter, and on average 89% for subcortical structures. The relative spatial overlap between the manual and the automated volumes was 97% for whole white matter, 92% for whole gray matter, and on average 75% for subcortical structures. For all pairs of structures rendered with the automated and the manual method, Pearson correlations were between r = 0.78 and r = 0.98 (P < 0.01, N = 28), except for globus pallidus, where r = 0.55 (left) and r = 0. 44 (right) (P < 0.01, N = 28). In the schizophrenia group, compared to the controls, we found a 16.7% increase in MRI volume for the basal ganglia (i.e., caudate nucleus, putamen, and globus pallidus), but no difference in total gray/white matter volume or in thalamic MR volume. This finding reproduces previously reported results, obtained in the same patient population with manually drawn structures, and suggests the utility/efficacy of our automated registration algorithm over more labor-intensive manual tracings.
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PMID:An automated registration algorithm for measuring MRI subcortical brain structures. 924 52

Brain structural deviation is known to be present in chronic patients with schizophrenia when compared with normal age-matched individuals. While the assumption is that these differences are based on a neurodevelopmental disturbance, whether they are static or continue to change throughout the disease process remains unknown. The following report describes a prospective follow-up study of first episode cases of schizophrenic illness. Analyses of MRI evaluations on an approximate annual basis for a minimum of four years are presented on 50 patients and 20 controls. Computer-assisted image analysis measuring the volume of several brain regions, using the program ANALYZE (Mayo Clinic), was performed on all scans. Patients were compared with controls for the rate of change over time in size of structures. No differences were found for the volumes of the caudate nucleus, temporal lobes, or hippocampus; and no changes in the degree of cerebral laterality were detected. However, there was a significant difference in the rate of change in the overall volumes of left and right hemispheres (P < 0.0004 and 0.001, respectively), right cerebellum (P < 0.02) and area of the isthmus of the corpus callosum (P < 0.05). The left cerebral ventricle had significantly greater enlargement over time when measured on coronal slice sequences (P < 0.02), but was not detected by axial views. These findings suggest that a subtle active brain process may be continuing through the first few years of a schizophrenic illness causing greater than the normal adult cortical deterioration. Further studies using other methods of image analysis and over a longer period of time are needed to determine the course and nature of this biologic process.
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PMID:Schizophrenia as a chronic active brain process: a study of progressive brain structural change subsequent to the onset of schizophrenia. 952 5

Dynamic susceptibility contrast magnetic resonance imaging (DSC MRI) provides a noninvasive means to create high resolution maps of the regional distribution of cerebral blood volume (CBV). Most DSC MRI studies conducted to date have focused on the evaluation of patients with cerebral neoplasms, ischemia or infarction, and epilepsy. However, preliminary work suggests that DSC MRI may also provide clinically important information for the evaluation of patients with neuropsychiatric disorders, especially dementia and schizophrenia. Additionally, with appropriate modification, DSC MRI may be used to reliably evaluate the effects of pharmacological challenges on cerebral hemodynamics. As pharmacotherapy is an important component in the treatment of a range of psychiatric disorders, the dynamic assessment of changes in cerebral perfusion associated with drug administration may ultimately lead to the development of "brain function tests" for a wide range of disorders.
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PMID:Dynamic susceptibility contrast magnetic resonance imaging in neuropsychiatry: present utility and future promise. 937 May 46


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