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The present study aimed to investigate the presence of corpus callosum (CC) volume deficits in a population-based recent-onset psychosis (ROP) sample, and whether CC volume relates to interhemispheric communication deficits. For this purpose, we used voxel-based morphometry comparisons of magnetic resonance imaging data between ROP (n =122) and healthy control (n = 94) subjects. Subgroups (38 ROP and 39 controls) were investigated for correlations between CC volumes and performance on the Crossed Finger Localization Test (CFLT). Significant CC volume reductions in ROP subjects versus controls emerged after excluding substance misuse and non-right-handedness. CC reductions retained significance in the schizophrenia subgroup but not in affective psychoses subjects. There were significant positive correlations between CC volumes and CFLT scores in ROP subjects, specifically in subtasks involving interhemispheric communication. From these results, we can conclude that CC volume reductions are present in association with ROP. The relationship between such deficits and CFLT performance suggests that interhemispheric communication impairments are directly linked to CC abnormalities in ROP., (Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.)

Objectives: The extent to which psychotic disorders fall into distinct diagnostic categories or can be regarded as lying on a single continuum is controversial. We compared lateral ventricle volumes between a large sample of patients with first-episode schizophrenia or bipolar disorder and a healthy control group from the same neighbourhood., Methods: Population-based MRI study with 88 first-episode psychosis (FEP) patients, grouped into those with schizophrenia/schizophreniform disorder (N=62), bipolar disorder (N=26) and 94 controls., Results: Right and left lateral ventricular and right temporal horn volumes were larger in FEP subjects than controls. Within the FEP sample, post-hoc tests revealed larger left lateral ventricles and larger right and left temporal horns in schizophrenia subjects relative to controls, while there was no difference between patients with bipolar disorder and controls. None of the findings was attributable to effects of antipsychotics., Conclusions: This large-sample population-based MRI study showed that neuroanatomical abnormalities in subjects with schizophrenia relative to controls from the same neighbourhood are evident at the first episode of illness, but are not detectable in bipolar disorder patients. These data are consistent with a model of psychosis in which early brain insults of neurodevelopmental origin are more relevant to schizophrenia than to bipolar disorder.

Objective: To describe a protocol that was based on an integrative neurobiological model of scientific investigation to better understand the pathophysiology of obsessive-compulsive disorder and to present the clinical and demographic characteristics of the sample., Method: A standardized research protocol that combines different methods of investigation (genetics, neuropsychology, morphometric magnetic resonance imaging and molecular neuroimaging of the dopamine transporter) obtained before and after treatment of drug-naïve adult obsessive-compulsive disorder patients submitted to a sequentially allocated 12-week clinical trial with a selective serotonin reuptake inhibitor (fluoxetine) and group cognitive-behavioral therapy., Results: Fifty-two treatment-naïve obsessive-compulsive disorder patients entered the clinical trial (27 received fluoxetine and 25 received group cognitive-behavioral therapy). At baseline, 47 blood samples for genetic studies, 50 neuropsychological evaluations, 50 morphometrical magnetic resonance images and 48 TRODAT-1 single-photon emission computed tomography (SPECT) exams were obtained. After 12 weeks, 38 patients completed the protocol (fluoxetine = 20 and GCBT = 18). Thirty-eight neuropsychological evaluations, 31 morphometrical magnetic resonance images and 34 TRODAT-1 SPECT exams were obtained post-treatment. Forty-one healthy controls matched for age, gender, socioeconomic status, level of education and laterality were submitted to the same research procedures at baseline., Conclusion: The comprehensive treatment response protocol applied in this project allowing integration on genetic, neuropsychological, morphometrical and molecular imaging of the dopamine transporter data in drug-naïve patients has the potential to generate important original information on the neurobiology of obsessive-compulsive disorder, and at the same time be clinically meaningful.

Background and Purpose: Several morphometric MR imaging studies have investigated age- and sex-related cerebral volume changes in healthy human brains, most often by using samples spanning several decades of life and linear correlation methods. This study aimed to map the normal pattern of regional age-related volumetric reductions specifically in the elderly population., Materials and Methods: One hundred thirty-two eligible individuals (67-75 years of age) were selected from a community-based sample recruited for the São Paulo Ageing and Health (SPAH) study, and a cross-sectional MR imaging investigation was performed concurrently with the second SPAH wave. We used voxel-based morphometry (VBM) to conduct a voxelwise search for significant linear correlations between gray matter (GM) volumes and age. In addition, region-of-interest masks were used to investigate whether the relationship between regional GM (rGM) volumes and age would be best predicted by a nonlinear model., Results: VBM and region-of-interest analyses revealed selective foci of accelerated rGM loss exclusively in men, involving the temporal neocortex, prefrontal cortex, and medial temporal region. The only structure in which GM volumetric changes were best predicted by a nonlinear model was the left parahippocampal gyrus., Conclusions: The variable patterns of age-related GM loss across separate neocortical and temporolimbic regions highlight the complexity of degenerative processes that affect the healthy human brain across the life span. The detection of age-related limbic GM decrease in men supports the view that atrophy in such regions should be seen as compatible with normal aging.

A subgroup of obsessive-compulsive disorder (OCD) patients remains refractory to conventional treatments. For them, a new stereotactic radiosurgery has been recently developed: the ventral capsular/ventral striatal (VC/VS) gamma capsulotomy. The authors aim to report efficacy and adverse events of VC/VS gamma capsulotomy. Five refractory OCD patients were selected. The authors assessed OCD, anxiety and depressive symptoms, and side effects pre- and postoperatively. Three patients (60%) met response criteria 48 months after surgery. Adverse effects were episodic and transient. Ventral capsular/ventral striatal gamma capsulotomy holds therapeutic promise, with few adverse effects.

Background: Neuropsychological deficits have been reported in association with first-episode psychosis (FEP). Reductions in grey matter (GM) volumes have been documented in FEP subjects compared to healthy controls. However, the possible inter-relationship between the findings of those two lines of research has been scarcely investigated., Objective: To investigate the relationship between neuropsychological deficits and GM volume abnormalities in a population-based sample of FEP patients compared to healthy controls from the same geographical area., Methods: FEP patients (n=88) and control subjects (n=86) were evaluated by neuropsychological assessment (Controlled Oral Word Association Test, forward and backward digit span tests) and magnetic resonance imaging using voxel-based morphometry., Results: Single-group analyses showed that prefrontal and temporo-parietal GM volumes correlated significantly (p<0.05, corrected) with cognitive performance in FEP patients. A similar pattern of direct correlations between neocortical GM volumes and cognitive impairment was seen in the schizophrenia subgroup (n=48). In the control group, cognitive performance was directly correlated with GM volume in the right dorsal anterior cingulate cortex and inversely correlated with parahippocampal gyral volumes bilaterally. Interaction analyses with "group status" as a predictor variable showed significantly greater positive correlation within the left inferior prefrontal cortex (BA46) in the FEP group relative to controls, and significantly greater negative correlation within the left parahippocampal gyrus in the control group relative to FEP patients., Conclusion: Our results indicate that cognitive deficits are directly related to brain volume abnormalities in frontal and temporo-parietal cortices in FEP subjects, most specifically in inferior portions of the dorsolateral prefrontal cortex.

Abnormalities in fronto-limbic-striatal white matter (WM) have been reported in bipolar disorder (BD), but results have been inconsistent across studies. Furthermore, there have been no detailed investigations as to whether acute mood states contribute to microstructural changes in WM tracts. In order to compare fiber density and structural integrity within WM tracts between BD depression and remission, whole-brain fractional anisotropy (FA) and mean diffusivity (MD) were assessed in 37 bipolar I disorder (BD-I) patients (16 depressed and 21 remitted), and 26 healthy individuals with diffusion tensor imaging. Significantly decreased FA and increased MD in bilateral prefronto-limbic-striatal white matter and right inferior fronto-occipital, superior and inferior longitudinal fasciculi were shown in all BD-I patients versus controls, as well as in depressed BD-I patients compared to both controls and remitted BD-I patients. Depressed BD-I patients also exhibited increased FA in the ventromedial prefrontal cortex. Remitted BD-I patients did not differ from controls in FA or MD. These findings suggest that BD-I depression may be associated with acute microstructural WM changes.

Neurobiological models support an involvement of white matter tracts in the pathophysiology of obsessive-compulsive disorder (OCD), but there has been little systematic evaluation of white matter volumes in OCD using magnetic resonance imaging (MRI). We investigated potential differences in the volume of the cingulum bundle (CB) and anterior limb of internal capsule (ALIC) in OCD patients (n=19) relative to asymptomatic control subjects (n=15). White matter volumes were assessed using a 1.5T MRI scanner. Between-group comparisons were carried out after spatial normalization and image segmentation using optimized voxel-based morphometry. Correlations between regional white matter volumes in OCD subjects and symptom severity ratings were also investigated. We found significant global white matter reductions in OCD patients compared to control subjects. The voxel-based search for regional abnormalities (with covariance for total white matter volumes) showed no specific white matter volume deficits in brain portions predicted a priori to be affected in OCD (CB and ALIC). However, large clusters of significant positive correlation with OCD severity scores were found bilaterally on the ALIC. These findings provide evidence of OCD-related ALIC abnormalities and suggest a connectivity dysfunction within frontal-striatal-thalamic-cortical circuits. Further studies are warranted to better define the role of such white matter alterations in the pathophysiology of OCD, and may provide clues for a more effectively targeting of neurosurgical treatments for OCD.

Objective: The purpose of this study was to investigate regional structural abnormalities in the brains of five patients with refractory obsessive-compulsive disorder (OCD) submitted to gamma ventral capsulotomy., Methods: We acquired morphometric magnetic resonance imaging (MRI) data before and after 1 year of radiosurgery using a 1.5-T MRI scanner. Images were spatially normalized and segmented using optimized voxel-based morphometry (VBM) methods. Voxelwise statistical comparisons between pre- and post-surgery MRI scans were performed using a general linear model. Findings in regions predicted a priori to show volumetric changes (orbitofrontal cortex, anterior cingulate gyrus, basal ganglia and thalamus) were reported as significant if surpassing a statistical threshold of p<0.001 (uncorrected for multiple comparisons)., Results: We detected a significant regional postoperative increase in gray matter volume in the right inferior frontal gyri (Brodmann area 47, BA47) when comparing all patients pre and postoperatively., Conclusions: Our results support the current theory of frontal-striatal-thalamic-cortical (FSTC) circuitry involvement in OCD pathogenesis. Gamma ventral capsulotomy is associated with neurobiological changes in the inferior orbitofrontal cortex in refractory OCD patients.

Although abnormalities in brain structures involved in the neurobiology of fear and anxiety have been implicated in the pathophysiology of panic disorder (PD), relatively few studies have made use of voxel-based morphometry (VBM) magnetic resonance imaging (MRI) to determine structural brain abnormalities in PD. We have assessed gray matter volume in 19 PD patients and 20 healthy volunteers using VBM. Images were acquired using a 1.5 T MRI scanner, and were spatially normalized and segmented using optimized VBM. Statistical comparisons were performed using the general linear model. A relative increase in gray matter volume was found in the left insula of PD patients compared with controls. Additional structures showing differential increases were the left superior temporal gyrus, the midbrain, and the pons. A relative gray matter deficit was found in the right anterior cingulate cortex. The insula and anterior cingulate abnormalities may be relevant to the pathophysiology of PD, since these structures participate in the evaluation process that ascribes negative emotional meaning to potentially distressing cognitive and interoceptive sensory information. The abnormal brain stem structures may be involved in the generation of panic attacks.

This is a comparative study between manual volumetry (MV) and voxel based morphometry (VBM) as methods of evaluating the volume of brain structures in magnetic resonance images. The volumes of the hippocampus and the amygdala of 16 panic disorder patients and 16 healthy controls measured through MV were correlated with the volumes of gray matter estimated by optimized modulated VBM. The chosen structures are composed almost exclusively of gray matter. Using a 4 mm Gaussian filter, statistically significant clusters were found bilaterally in the hippocampus and in the right amygdala in the statistical parametric map correlating with the respective manual volume. With the conventional 12 mm filter,a significant correlation was found only for the right hippocampus. Therefore, narrow filters increase the sensitivity of the correlation procedure, especially when small brain structures are analyzed. The two techniques seem to consistently measure structural volume.

Background: In low- and middle-income countries people with schizophrenia are reported to experience better outcomes than those in high-income countries., Aims: To examine structural brain differences in people with first-episode psychosis and controls in Brazil., Method: Magnetic resonance imaging using voxel-based morphometry was performed on 122 people with first-episode psychosis and 94 controls., Results: There were significant decreases in grey matter in the left superior temporal and inferior prefrontal cortices, insula bilaterally and the right hippocampal region in first-episode psychosis (P<0.05, corrected for multiple comparisons). The subgroup of people with schizophrenia (n=62) exhibited a similar pattern of decrease in grey matter relative to controls., Conclusions: Structural abnormalities reported in psychosis in high-income countries are also present in first-episode psychosis in Brazil.

Purpose: To evaluate the feasibility of using the Statistical Parametric Mapping (SPM) program for an automated, voxel-by-voxel assessment of regional cerebral blood flow (rCBF) deficits in Alzheimer's disease (AD) subjects relative to age-matched controls studied with a conventional, single-detector SPECT system., Methods: We used a databank of 99mTc-HMPAO images of 19 patients with a diagnosis of probable AD and 15 elderly healthy volunteers; data were acquired using an Orbiter-Siemens single-detector SPECT system. Using SPM, images were transformed spatially, smoothed (12mm), and the data were compared on a voxel-by-voxel basis with t-tests., Results: There were significant rCBF reductions in AD patients relative to controls involving regions predicted a priori to be affected in AD, namely the left temporal and parietal neocortices, and the right posterior cingulate gyrus (p<0.05, corrected for multiple comparisons)., Discussion: The location of rCBF reductions in AD subjects in our study is consistent with the deficits detected in previous functional imaging studies of AD using higher-resolution devices. This suggests the potential usefulness of using SPM for the analysis of data acquired with single-detector SPECT systems, despite the limited sensitivity and spatial resolution of such equipment.

Several recent magnetic resonance imaging studies have employed voxel-based morphometry (VBM) to detect regional gray matter volume abnormalities in Alzheimer's disease (AD). However, investigations of corpus callosum (CC) abnormalities in AD using this automated methodology have been scarce, and no VBM study investigated correlations between regional CC atrophy and cognitive measurements in AD subjects at mild disease stages. We used VBM to compare the topography of CC volume differences between 14 AD subjects (MMSE 14-25) and 14 healthy volunteers. Images were acquired using a 1.5-Telsa scanner, and were spatially normalized and segmented using optimized VBM. Statistical comparisons were performed using the general linear model. Significant CC atrophy was detected in the antero-superior portion of the splenium, the isthmus, the anterior and posterior portions of the CC body, and the rostral portion of the genu. Voxels showing peak statistical difference were all left-sided (P<0.001, uncorrected for multiple comparisons). A cluster of significant positive correlation with MMSE scores was seen on the left anterior CC body. Our results confirm previous findings of diffuse volumetric CC reductions early in the course of AD, and warrant further evaluation of the relevance of atrophic changes in anterior CC portions to the cognitive impairments that characterize the disorder.

Background: Several structural magnetic resonance imaging (MRI) studies have investigated the presence of brain abnormalities in obsessive-compulsive disorder (OCD) but have not produced consistent findings. This might be partly related to their use of a regions-of-interest approach. We assessed gray matter volumes in 19 OCD subjects and 15 healthy volunteers, using voxel-based morphometry (VBM)., Methods: Images were acquired with a 1.5-T MRI scanner, spatially normalized, and segmented with optimized VBM. Statistical comparisons were performed with the general linear model., Results: Significant findings were detected in regions predicted a priori to be implicated in OCD, including increased gray matter in OCD subjects relative to control subjects in posterior orbitofrontal and parahippocampal regions; decreased gray matter in OCD patients in the left anterior cingulate cortex; and inverse correlations between obsessive-compulsive symptom severity and gray matter in the medial thalamus (p < .001, uncorrected for multiple comparisons). Also, an unpredicted site of gray matter reduction in OCD patients in the right parietal associative cortex approached significance (p = .052, corrected for multiple comparisons)., Conclusions: Our findings are consistent with previous studies implicating dysfunction of orbitofrontal, cingulate, thalamic, and temporolimbic regions in OCD and suggest that the involvement of the parietal cortex in the pathophysiology of OCD warrants further investigation.