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Geraldo F Busatto

Publications and source records attributed to Geraldo F Busatto.

At least 19 recordsLinked to original sources
PubMed2007

Insight and regional brain volumes in schizophrenia.

We have investigated the relationship between insight impairment and regional brain volumes (gray and white matter) in schizophrenia using voxel-based morphometry (VBM). Fifty patients with schizophrenia were evaluated using the Scale for Unawareness of Mental Disorders. Magnetic resonance images were acquired, segmented and spatially normalized using optimized VBM routines. No significant inverse correlations were detected between insight impairment and gray or white matter volumes in the prefrontal region (where significant findings had been predicted a priori), or in any other brain areas. Our results do not support previous hypotheses suggesting a relationship between frontal lobe atrophy and impaired insight in patients with schizophrenia.

Adolescent↗
PubMed2006

Volumetric reduction of the corpus callosum in Alzheimer's disease in vivo as assessed with voxel-based morphometry.

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.

Aged↗
PubMed2006

Cognitive deficits in first-episode psychosis: a population-based study in São Paulo, Brazil.

BACKGROUND: Studies conducted in high-income countries have reported significant cognitive deficits in first on set schizophrenia subjects relative to asymptotic controls, and it has been suggested that the severity of such deficits could be directly related to the duration of untreated psychosis (DUP). It is relevant to conduct similar studies in developing countries, given the supposedly better outcome for schizophrenia patients living in the latter environments. METHODS: We applied verbal fluency and digit span tests to an epidemiological-based series of patients with first-onset psychoses (n=179) recruited in the city of São Paulo, and compared the findings with those from non-psychotic control subjects randomly selected from the same geographical areas (n=383). RESULTS: Psychosis subjects showed lower scores on the three tests relative to controls, with greatest between-group differences for the backward digit span task (p<0.0001). There were no significant differences between subjects with affective and schizophreniform psychosis. Cognitive performance indices were negatively correlated with the severity of negative symptoms, but showed no relation to DUP. CONCLUSION: We found significant cognitive deficits in patients investigated early during the course of psychotic disorders in an environment that is distinct from those where the subjects investigated in previous studies have been drawn from. We found no support to the hypothesis of an association between greater cognitive deficits and a longer DUP.

Adult↗
PubMed2006

Late onset bipolar disorder associated with white matter hyperintensities: a pathophysiological hypothesis.

Vascular depression is, nowadays, a well-established concept in the literature. However, the possible emergence of late onset bipolar disorder in subjects with no antecedents of mood disorder or after a chronic or recurrent course of unipolar depression constitutes a poorly studied issue, despite its importance in clinical practice. Here, we present the case of a 72-year-old female patient who began to present recurrent major depressive symptoms, resistant to pharmacological treatment, from the age of 58. Three years later, she started to present phases of mania with rapid cycling features. A brain MRI scan showed prominent white matter hyperintensities (WMH). WMH are frequently found in the elderly population, but with greater burden in individuals with hypertension and cerebrovascular disease. WMH impair cortical function and damage the cerebral tissue. WMH have been associated with adult-onset bipolar disorder and late onset depression, and are linked to a worse prognosis of both conditions. The present case report highlights the possibility that vascular-related WMH may provoke late onset bipolar disorder by damaging frontolimbic circuits implicated in the pathophysiology of mania.

Aged↗
PubMed2006

Association between major depressive symptoms in heart failure and impaired regional cerebral blood flow in the medial temporal region: a study using 99m Tc-HMPAO single photon emission computerized tomography (SPECT).

BACKGROUND AND PURPOSE: Depressive symptoms are frequently associated with heart failure (HF), but the brain mechanisms underlying such association are unclear. We hypothesized that the presence of major depressive disorder (MDD) emerging after the onset of HF would be associated with regional cerebral blood flow (rCBF) abnormalities in medial temporal regions previously implicated in primary MDD, namely the hippocampus and parahippocampal gyrus. METHOD: Using 99mTc-SPECT, we measured rCBF in 17 elderly MDD-HF patients, 17 non-depressed HF patients, and 18 healthy controls, matched for demographic variables. Group differences were investigated with Statistical Parametric Mapping. RESULTS: Significant rCBF reductions in MDD-HF patients relative to both non-depressed HF patients and healthy controls were detected in the left anterior parahippocampal gyrus and hippocampus (ANOVA, p=0.008 corrected for multiple comparisons) and the right posterior hippocampus and parahippocampal gyrus (p=0.005 corrected). In the overall HF group, there was a negative correlation between the severity of depressive symptoms and rCBF in the right posterior hippocampal/parahippocampal region (p=0.045 corrected). CONCLUSIONS: These findings are consistent with the notion that the medial temporal region is vulnerable to brain perfusion deficits associated with HF, and provide evidence that such functional deficits may be specifically implicated in the pathophysiology of MDD associated with HF.

Aged↗
PubMed2006

Cavum septum pellucidum and adhesio interthalamica in schizophrenia: an MRI study.

Several studies have independently suggested that patients with schizophrenia are more likely to have an enlarged cavum septum pellucidum (CSP) and an absent adhesio interthalamica (AI), respectively. However, neither finding has been consistently replicated and it is unclear whether there is an association between these two midline brain abnormalities. Thus, we compared the prevalence of absent AI and the prevalence, size and volume of CSP in 38 patients with schizophrenia and 38 healthy controls using magnetic resonance imaging (MRI). There were no between group differences in the presence or volume of CSP; however, an enlarged CSP was commoner among patients than controls. There was also a positive correlation between CSP ratings and volumes. No differences in the presence or absence of the AI were found between patients and controls; however, an absent AI was commoner in male patients with schizophrenia than females. There was absolutely no overlap between the presence of a large CSP and an absence of AI. In conclusion, our findings are in line with several case series and other MRI investigations that have shown a higher incidence of putatively developmental brain abnormalities in patients with schizophrenia, particularly in males, and support the neurodevelopmental model of this disorder.

Adult↗
PubMed2006

Phonemic fluency in Portuguese-speaking subjects in Brazil: ranking of letters.

Phonological verbal fluency studies in English most commonly employ the letters F-A-S as stimuli. We assessed the production of words with these and 14 other letters in Portuguese-speaking healthy subjects (n = 74). The letters F-A-S were ranked among the easiest to produce words in one minute, which is consistent with the findings of studies with English-speaking subjects. There were differences in the overall ranking of letters depending on whether the total word number or the latency between words were considered. Our findings provide a databank of phonological verbal fluency performance using different stimuli in Portuguese, and demonstrate that the ranking of the letters F-A-S is comparable between the English and Portuguese languages in terms of the level of difficulty to produce words, when the task is used in its traditional format.

Adolescent↗
PubMed2006

Regional cerebral blood flow reductions, heart failure and Alzheimer's disease.

OBJECTIVES: To discuss whether there are similarities between the functional brain abnormalities detectable in association with the diagnoses of heart failure (HF) and Alzheimer's disease (AD), focusing particularly on neuroimaging findings in vivo. METHODS: Using an electronic database (Medline), we reviewed imaging studies that have evaluated resting cerebral blood flow (CBF), resting glucose metabolism or amyloid deposition in groups of subjects suffering AD or HF compared with healthy controls. RESULTS: Single photon emission computed tomography (SPECT) investigations have reported global CBF reductions in HF groups compared with controls. In one recent SPECT study using modern voxel-based methods for image analysis, regional CBF deficits in the pre-cuneus and posterior cingulate gyrus were detected in a sample of HF sufferers relative to controls. The regional distribution of functional deficits in the latter study was similar to that found in many positron emission tomography (PET) investigations of glucose metabolism at early AD stages, as well as in recent PET investigations of amyloid deposition in AD. DISCUSSION: Imaging studies have rarely investigated whether there are localized functional brain deficits in association with HF. Recent regional CBF SPECT data provide preliminary anatomic support to a view that AD-like brain changes may develop in HF patients, possibly as a consequence of chronic CBF reductions. Additional studies of larger HF samples are needed to confirm this possibility, preferably using PET measures that have afforded greater sensitivity and specificity to identify brain functional abnormalities associated with the diagnosis of AD, such as indices of glucose metabolism and amyloid deposition.

Alzheimer Disease↗
PubMed2005

Frontal and anterior cingulate activation during overt verbal fluency in patients with first episode psychosis.

OBJECTIVE: Functional neuroimaging studies using phonological verbal fluency tasks allow the assessment of neural circuits relevant to the neuropsychology of psychosis. There is evidence that the prefrontal cortex and anterior cingulate gyrus present different activation patterns in subjects with chronic schizophrenia relative to healthy controls. We assessed the functioning in these brain regions during phonological verbal fluency in subjects with recent-onset functional psychoses, using functional magnetic resonance imaging (FMRI). METHODS: Seven patients with functional psychoses (3 schizophreniform, 4 affective) and 9 healthy controls were studied. We compared functional magnetic resonance images acquired during articulation of words beginning with letters classified as easy for word production in Portuguese. Statistical comparisons were performed using non-parametric tests. RESULTS: There were no differences between patients and controls in task performance. Controls showed greater activation than patients in the left rostral anterior cingulate gyrus and right inferior prefrontal cortex, whereas patients showed stronger activation than controls in a more dorsal part of the anterior cingulate gyrus bilaterally and in a more superior portion of the right prefrontal cortex. CONCLUSION: Our preliminary findings of attenuated engagement of inferior prefrontal cortex and anterior cingulate gyrus in patients with recent onset psychosis during phonological verbal fluency are consistent with those of previous studies. The greater activation found in other parts of the anterior cingulate gyrus and prefrontal cortex in patients may be related to a compensatory response that is required to maintain normal task performance, and suggests a pattern of disorganized activity of different functional anterior cingulate gyrus units in association with psychotic conditions.

Adult↗
PubMed2005

Relationship between regional cerebral blood flow and separate symptom clusters of major depression: a single photon emission computed tomography study using statistical parametric mapping.

This study examined the relationship between resting regional cerebral blood flow (rCBF) patterns in patients with major depressive disorder (MDD) and specific symptom clusters derived from ratings on the Hamilton Rating Scale for Depression (HRSD) and the Mini Mental State Examination. We hypothesized that the functional activity in frontal, parietal, anterior cingulate, basal ganglia and limbic regions would be related to specific symptom domains. Fifteen patients fulfilling DSM-IV criteria for MDD who were off all psychotropic medications for >4 weeks and 15 normal volunteers were recruited. Single photon emission computed tomography (SPECT) images were obtained after (99m)Tc-ECD injection, and correlations between rCBF patterns and symptom severity ratings were calculated on a voxel-by-voxel basis, using statistical parametric mapping (SPM). Severity of depressive mood was inversely correlated with rCBF in the left amygdala, lentiform nucleus, and parahippocampal gyrus, and directly correlated with rCBF in the right postero-lateral parietal cortex (p < 0.001, uncorrected for multiple comparisons). Insomnia severity was inversely correlated with rCBF in the right rostral and subgenual anterior cingulate cortices, insula and claustrum. Anxiety severity was directly correlated with rCBF in the right antero-lateral orbitofrontal cortex, while cognitive performance was directly correlated with rCBF in the right postero-medial orbitofrontal cortex and in the left lentiform nucleus. Our findings confirmed the prediction that separate symptom domains of the MDD syndrome are related to specific rCBF patterns, and extend results from prior studies that suggested the involvement of anterior cingulate, frontal, limbic and basal ganglia regions in the pathophysiology of MDD.

Adolescent↗
PubMed2005

Regional gray matter abnormalities in obsessive-compulsive disorder: a voxel-based morphometry study.

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.

Adult↗
PubMed2005

Localized cerebral blood flow reductions in patients with heart failure: a study using 99mTc-HMPAO SPECT.

BACKGROUND AND PURPOSE: Reduced resting global cerebral blood flow has been previously detected in association with heart failure (HF), but it is not clear whether there are brain regions that could be specifically affected by those brain perfusion deficits. The authors used a fully automated, voxel-based image analysis method to investigate, across the entire cerebral volume, the presence of resting regional cerebral blood flow (rCBF) abnormalities in HF patients compared to healthy controls. METHODS: rCBF was evaluated with 99mTc-single-photon emission computed tomography in 17 HF patients (New York Heart Association functional class II or III) and 18 elderly healthy volunteers. Voxel-based analyses of rCBF data were conducted using the statistical parametric mapping software. RESULTS: Significant rCBF reductions in HF patients relative to controls (P<.05, corrected for multiple comparisons) were detected in 2 foci, encompassing, respectively, the left and right precuneus and cuneus and the right lateral temporoparietal cortex and posterior cingulated gyrus. In the HF group, there was also a significant direct correlation between the degree of cognitive impairment as assessed using the Cambridge Mental Disorders of the Elderly Examination and rCBF on a voxel cluster involving the right posterior cingulate cortex and precuneus, located closely to the site where between-group rCBF differences had been identified. CONCLUSIONS: These preliminary findings indicate that posterior cortical areas of the brain may be particularly vulnerable to brain perfusion reductions associated with HF and suggest that functional deficits in these regions might be relevant to the pathophysiology of the cognitive impairments presented by HF patients.

Aged↗
PubMed2003

Rightward cerebral asymmetry in subtypes of schizophrenia according to Leonhard's classification and to DSM-IV: a structural MRI study.

Although well documented, brain structural abnormalities in schizophrenia are non-specific, and morphometric parameters show significant overlap between patients and healthy controls. Such inconsistencies in neuroimaging findings could represent different levels of severity along a single pathogenic process or distinct clinical and etiopathological psychoses within a schizophrenic spectrum. The aim of the present study was the investigation of distinct brain abnormalities in different subtypes of schizophrenia. Forty patients were classified according to DSM-IV and Leonhard's classifications. Psychopathology was assessed by the Positive and Negative Syndrome Scale (PANSS) and the Negative Symptom Rating Scale (NSRS). Patients were compared to 20 healthy volunteers on volumetric measures of cerebral structures (hemisphere, hippocampus and planum temporale) and ventricular-brain ratio (VBR) obtained by magnetic resonance imaging. Patients showed rightward asymmetry of cerebral hemispheres and increased VBR. Rightward asymmetry correlated with severity of negative symptoms and prevailed in the systematic forms of Leonhard, suggesting a distinct pattern of left hemisphere abnormality in this subgroup of psychoses. Increased VBR values showed a single normal distribution in the subgroups, indicating that ventricular enlargement is not restricted to a subgroup but is present to a certain degree in all cases.

Adult↗
PubMed2003

Reduced cortical folding in schizophrenia: an MRI morphometric study.

OBJECTIVE: Although well documented, regional brain structural abnormalities in schizophrenia are nonspecific, and morphometric parameters show significant overlapping between patients and healthy comparison subjects. An increasing number of studies have focused on supraregional models involving abnormalities of the neuronal circuitry between cortical regions in schizophrenia. The aim of the present study was to investigate cortical folding as an index of the neuronal wiring in different subtypes of schizophrenia. METHOD: Magnetic resonance imaging measures of gyrification index in intervals of 3.6 mm along the total cerebral cortex were compared in 40 patients with DSM-IV schizophrenia and 20 healthy subjects. Psychopathology was assessed with the Positive and Negative Syndrome Scale, Brief Psychiatric Rating Scale, and the Negative Symptom Rating Scale. RESULTS: The schizophrenia patients showed significantly reduced bilateral cortical folding relative to healthy comparison subjects. Such reductions were more pronounced in those with the disorganized subtype and showed an inverse correlation with negative symptoms and a positive correlation with positive symptoms. The paranoid subtype showed reduced cortical folding that was restricted to the left hemisphere. CONCLUSIONS: These results from a larger patient group confirm a previous report of reduced cortical folding in schizophrenia patients. They also suggest a distinct pattern of abnormality between schizophrenia subtypes regarding the process of cerebral lateralization and are in agreement with the neurodevelopmental hypothesis of schizophrenia.

Adult↗
PubMed2002

Psychotic symptoms in major depressive disorder are associated with reduced regional cerebral blood flow in the subgenual anterior cingulate cortex: a voxel-based single photon emission computed tomography (SPECT) study.

BACKGROUND: Delusions and/or hallucinations are not an uncommon feature in severe major depressive episodes. Functional imaging studies of depression have been widely reported in the literature, but few of these have attempted to investigate the neurophysiological correlates of psychotic symptoms. METHODS: We measured resting regional cerebral blood flow (rCBF) with the (99m)Tc-ECD SPECT technique in patients with major depressive disorder with (n=9) and without (n=12) psychotic features, as well as in a group of healthy volunteers (n=12). Between-group rCBF comparisons were performed using the voxel-based statistical parametric mapping method. RESULTS: Major depressed patients with psychotic features showed decreased rCBF in the left subgenual anterior cingulate cortex relative to both non-psychotic patients and healthy controls (P<0.001 one-tailed, uncorrected for multiple comparisons). Relative to the non-psychotic group, depressed patients with psychotic symptoms also had a focus of decreased rCBF in the right inferior frontal cortex, with the voxel of maximal significance in the insula (P<0.031, corrected for multiple comparisons). A similar pattern of significant between-group rCBF differences between psychotic and non-psychotic patients emerged after covarying the analysis for the confounding influence of overall illness severity. CONCLUSIONS: These results provide preliminary evidence that psychotic symptoms in major depression may be associated with abnormalities in ventral paralimbic regions previously implicated in mood regulation and depression.

Adult↗
PubMedDate not supplied

A voxel-based morphometry study of temporal lobe gray matter reductions in Alzheimer's disease.

Several MRI studies have reported reductions in temporal lobe volumes in Alzheimer's disease (AD). Measures have been usually obtained with regions-of-interest (ROI) drawn manually on selected medial and lateral portions of the temporal lobes, with variable choices of anatomical borders across different studies. We used the fully automated voxel-based morphometry (VBM) approach to investigate gray matter abnormalities over the entire extension of the temporal lobe in 14 AD patients (MMSE 14-25) and 14 healthy controls. Foci of significantly reduced gray matter volume in AD patients were detected in both medial and lateral temporal regions, most significantly in the right and left posterior parahippocampal gyri and the left posterior inferior temporal gyrus/fusiform gyrus (P<0.05, corrected for multiple comparisons). At a more flexible statistical threshold (P<0.001, uncorrected for multiple comparisons), circumscribed foci of significant gray matter reduction were also detected in the right amygdala/enthorinal cortex, the anterior and posterior borders of the superior temporal gyrus bilaterally, and the anterior portion of the left middle temporal gyrus. These VBM results confirm previous findings of temporal lobe atrophic changes in AD, and suggest that these abnormalities may be confined to specific sites within that lobe, rather than showing a widespread distribution.

Aged↗