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INTRODUCTION: Cerebellar alterations, including both volumetric changes in the cerebellar vermis and dysfunctions of the corticocerebellar connections, have been documented in psychotic disorders. Starting from the clinical observation of a bipolar patient with cerebellar hypoplasia, the purpose of this review is to summarize the data in the literature about the association between hypoplasia of the cerebellar vermis and psychotic disorders [schizophrenia (SCZ) and bipolar disorder (BD)]. METHODS: A bibliographic search on PubMed has been conducted, and 18 articles were finally included in the review: five used patients with BD, 12 patients with SCZ and one subject at psychotic risk. RESULTS: For SCZ patients and subjects at psychotic risk, the results of most of the reviewed studies seem to suggest a gray matter volume reduction coupled with an increase in white matter volumes in the cerebellar vermis, compared to healthy controls. Instead, the results of the studies on BD patients are more heterogeneous with evidence showing a reduction, no difference or even an increase in cerebellar vermis volume compared to healthy controls. CONCLUSIONS: From the results of the reviewed studies, a possible correlation emerged between cerebellar vermis hypoplasia and psychotic disorders, especially SCZ, ultimately supporting the hypothesis of psychotic disorders as neurodevelopmental disorders.
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Trastorno Bipolar , Vermis Cerebeloso , Trastornos Psicóticos , Esquizofrenia , Adulto , Femenino , Humanos , Trastorno Bipolar/patología , Vermis Cerebeloso/diagnóstico por imagen , Vermis Cerebeloso/patología , Cerebelo/diagnóstico por imagen , Cerebelo/patología , Cerebelo/anomalías , Discapacidades del Desarrollo , Imagen por Resonancia Magnética , Malformaciones del Sistema Nervioso , Trastornos Psicóticos/patología , Trastornos Psicóticos/diagnóstico por imagen , Esquizofrenia/diagnóstico por imagen , Esquizofrenia/patologíaRESUMEN
BACKGROUND: Alterations in insular grey matter (GM) volume has been consistently reported for affective and non-affective psychoses both in chronic and first-episode patients, ultimately suggesting that the insula might represent a good region to study in order to assess the longitudinal course of psychotic disorders. Therefore, in this longitudinal Magnetic Resonance Imaging (MRI) study, we aimed at further investigating the key role of insular volumes in psychosis. MATERIAL AND METHODS: 68 First-Episode Psychosis (FEP) patients, 68 patients with Schizophrenia (SCZ), 47 Bipolar Disorder (BD) patients, and 94 Healthy Controls (HC) were enrolled and underwent a 1.5 T MRI evaluation. A subsample of 99 subjects (10 HC, 23 BD, 29 SCZ, 37 FEP) was rescanned after 2,53 ± 1,68 years. The insular cortex was manually traced and then divided into an anterior and posterior portion. Group and correlation analyses were then performed both at baseline and at follow-up. RESULTS: At baseline, greater anterior and lower posterior insular GM volumes were observed in chronic patients. At follow-up, we found that FEP patients had a significant GM volume increase from baseline to follow-up, especially in the posterior insula whereas chronic patients showed a relative stability. Finally, significant negative correlations between illness severity and pharmacological treatment and insular GM volumes were observed in the whole group of psychotic patients. CONCLUSIONS: The longitudinal assessment of both chronic and first-episode patients allowed us to detect a complex pattern of GM abnormalities in selective sub-portions of insular volumes, ultimately suggesting that this structure could represent a key biological marker of psychotic disorders.
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Trastornos Psicóticos , Esquizofrenia , Corteza Cerebral/diagnóstico por imagen , Sustancia Gris/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética/métodos , Trastornos Psicóticos/diagnóstico por imagen , Esquizofrenia/diagnóstico por imagenRESUMEN
BACKGROUND: Psychopathological symptoms during euthymia in Bipolar Disorder (BD) affect quality of life and predispose to the occurrence of new acute episodes, however only few studies investigated potential risk-factors. This study aims to explore the association between childhood trauma (CT), lifetime stressful events (SLEs) and psychopathological symptoms in BD patients during euthymia and controls (HC). METHODS: A total of 261 participants (93 euthymic patients with BD, 168 HC) were enrolled. Generalized linear models and multiple logistic models were used to assess the association among the Symptom Check List-90-R (SCL-90-R), the Infancy Trauma Interview, the Paykel Life Events Scale. RESULTS: The rate of participants reporting CT was higher in BD (n=47; 53%) than HC (n=43; 30%) (p=0.001). The experience of neglect was strongly related to BD (OR 6.5; p=0.003). CT was associated to higher scores on the SCL-90-R subscales (all the subscales except Phobia). No effects of the interaction between CT and diagnosis were found on SCL-90-R. Finally, there was a main effect of CT on lifetime SLEs (p<.001), that was not associated with diagnosis (p=0.833), nor with the interaction between CT and diagnosis (p=0.624). LIMITATIONS: The cross-sectional design does not allow causal inferences; the exclusion of subjects reporting medical or psychiatric comorbidity limits generalizability. CONCLUSIONS: CT was associated both to psychopathological symptoms during euthymia and the lifetime SLEs, thus it may represent a vulnerability factor influencing the course of BD. Overall, these data contribute to overcome the limited evidences documenting the influence of environmental factors on euthymic phase in BD.
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Trastorno Bipolar , Trastorno Bipolar/epidemiología , Estudios Transversales , Trastorno Ciclotímico , Voluntarios Sanos , Humanos , Calidad de VidaRESUMEN
BACKGROUND: Patterns of coordinated variations of gray matter (GM) morphology across individuals are promising indicators of disease. However, it remains unclear if they can help characterize first-episode psychosis (FEP) and symptoms' severity. METHODS: Sixty-seven FEP and 67 matched healthy controls (HC) were assessed with structural MRI to evaluate the existence of distributed GM structural covariance patterns associated to brain areas belonging to salience network. Voxel-based morphometry (VBM) and structural covariance differences, investigated with salience network seed-based Partial Least Square, were applied to explore differences between groups. GM density associations with Raven's intelligent quotient (IQ) and Positive and Negative Syndrome Scale (PANSS) scores were investigated. RESULTS: Univariate VBM results gave trend without significant GM differences across groups. GM and IQ correlated positively in both groups: in FEP, mostly in hippocampus, insula, and fronto-temporal structures, while in HC mostly in amygdala, thalamus and fronto-temporal regions. GM and PANSS scores correlated negatively in FEP, with widespread clusters located in limbic regions. Multivariate analysis showed strong and opposite structural GM covariance with salience network for FEP and HC. Moreover, structural covariance of the salience network in FEP correlated negatively with severity of clinical symptoms. CONCLUSION: Our study provides evidence supporting the insular dysfunction model of psychosis. Reduced structural GM covariance of the salience network, with its association to symptom's severity, appears a promising morphometry feature for FEP detection.
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Trastornos Psicóticos , Encéfalo/diagnóstico por imagen , Corteza Cerebral/diagnóstico por imagen , Sustancia Gris/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética , Trastornos Psicóticos/diagnóstico por imagenRESUMEN
OBJECTIVES: Bipolar disorder (BD) is a psychiatric condition causing shifts in mood, energy and activity levels severely altering the quality of life of the patients even in the euthymic phase. Although widely accepted, the neurobiological bases of the disorder in the euthymic phase remain elusive. This study aims at characterizing resting state functional activity of the BD euthymic phase in order to better understand the pathogenesis of the disease and build future neurobiological models. METHODS: Fifteen euthymic BD patients (10 females; mean age 40.2; standard deviation 13.5; range 20-61) and 27 healthy controls (HC) (21 females; mean age 37; standard deviation 10.6; range 22-60) underwent a 3T functional MRI scan at rest. Resting state activity was extracted through independent component analysis (ICA) run with automatic dimensionality estimation. RESULTS: ICA identified 22 resting state networks (RSNs). Within-network analysis revealed decreased connectivity in the visual, temporal, motor and cerebellar RSNs of BD patients vs HC. Between-network analysis showed increased connectivity between motor area and the default mode network (DMN) partially overlapping with the fronto-parietal network (FPN) in BD patients. CONCLUSION: Within-network analysis confirmed existing evidence of altered cerebellar, temporal, motor and visual networks in BD. Increased connectivity between the DMN and the motor area network suggests the presence of alterations of the fronto-parietal regions, precuneus and cingulate cortex in the euthymic condition. These findings indicate that specific connectivity alterations might persist even in the euthymic state suggesting the importance of examining both within and between-network connectivity to achieve a global understanding of the BD euthymic condition.
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Trastorno Bipolar/fisiopatología , Trastorno Ciclotímico/fisiopatología , Adulto , Encéfalo/fisiopatología , Mapeo Encefálico , Estudios de Casos y Controles , Cerebelo/fisiopatología , Femenino , Giro del Cíngulo/fisiopatología , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Lóbulo Parietal/fisiopatología , Calidad de Vida , Adulto JovenRESUMEN
Neurodevelopment represents a period of increased opportunity and vulnerability, during which a complex confluence of genetic and environmental factors influences brain growth trajectories, cognitive and mental health outcomes. Recently, magnetic resonance imaging (MRI) studies on twins have increased our knowledge of the extent to which genes, the environment and their interactions shape inter-individual brain variability. The present review draws from highly salient MRI studies in young twin samples to provide a robust assessment of the heritability of structural and functional brain changes during development. The available studies suggest that (as with many other traits), global brain morphology and network organization are highly heritable from early childhood to young adulthood. Conversely, genetic correlations among brain regions exhibit heterogeneous trajectories, and this heterogeneity reflects the progressive, experience-related increase in brain network complexity. Studies also support the key role of environment in mediating brain network differentiation via changes of genetic expression and hormonal levels. Thus, rest- and task-related functional brain circuits seem to result from a contextual and dynamic expression of heritability.
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Encéfalo/anatomía & histología , Encéfalo/fisiología , Interacción Gen-Ambiente , Desarrollo Humano/fisiología , Red Nerviosa/anatomía & histología , Red Nerviosa/fisiología , Neuroimagen , Estudios en Gemelos como Asunto , Adolescente , Adulto , Encéfalo/diagnóstico por imagen , Encéfalo/crecimiento & desarrollo , Niño , Preescolar , Humanos , Lactante , Red Nerviosa/diagnóstico por imagen , Red Nerviosa/crecimiento & desarrollo , Adulto JovenAsunto(s)
Antipsicóticos/efectos adversos , Enfermedad Hepática Inducida por Sustancias y Drogas/etiología , Clorpromazina/efectos adversos , Olanzapina/efectos adversos , Antipsicóticos/uso terapéutico , Clorpromazina/uso terapéutico , Terapia Combinada , Humanos , Masculino , Persona de Mediana Edad , Olanzapina/uso terapéutico , Esquizofrenia/tratamiento farmacológicoRESUMEN
Background: Hippocampal abnormalities have been largely reported in patients with schizophrenia and bipolar disorder, and are considered to be involved in the pathophysiology of the psychosis. The hippocampus consists of several subfields but it remains unclear their involvement in the early stages of psychosis. Aim: The aim of this study was to investigate volumetric alterations in hippocampal subfields in patients at the first-episode psychosis (FEP). Methods: Magnetic resonance imaging (MRI) data were collected in 134 subjects (58 FEP patients; 76 healthy controls [HC]). A novel automated hippocampal segmentation algorithm was used to segment the hippocampal subfields, based on an atlas constructed from ultra-high resolution imaging on ex vivo hippocampal tissue. The general linear model was used to investigate volume differences between FEP patients and HC, with age, gender and total intracranial volume as covariates. Results: We found significantly lower volumes of bilateral CA1, CA4, and granule cell layer (GCL), and of left CA3, and left molecular layer (ML) in FEP patients compared to HC. Only the volumes of the left hippocampus and its subfields were significantly lower in FEP than HC at the False Discovery Rate (FDR) of 0.1. No correlation was found between hippocampal subfield volume and duration of illness, age of onset, duration of medication, and Positive and Negative Syndrome Scale (PANSS). Conclusion: We report abnormally low volumes of left hippocampal subfields in patients with FEP, sustaining its role as a putative neural marker of psychosis onset.
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Trastorno Bipolar/patología , Hipocampo/patología , Procesamiento de Imagen Asistido por Computador/métodos , Imagen por Resonancia Magnética/métodos , Trastornos Psicóticos/patología , Esquizofrenia/patología , Trastorno de la Personalidad Esquizotípica/patología , Adulto , Trastorno Bipolar/diagnóstico por imagen , Región CA1 Hipocampal/diagnóstico por imagen , Región CA1 Hipocampal/patología , Región CA3 Hipocampal/diagnóstico por imagen , Región CA3 Hipocampal/patología , Femenino , Hipocampo/diagnóstico por imagen , Humanos , Masculino , Persona de Mediana Edad , Trastornos Psicóticos/diagnóstico por imagen , Esquizofrenia/diagnóstico por imagen , Trastorno de la Personalidad Esquizotípica/diagnóstico por imagen , Adulto JovenRESUMEN
The parietal lobe (PL) supports cognitive domains, including attention and memory, which are impaired in bipolar disorder (BD). Although cross-sectional voxel-based morphometry studies found reduced PL grey matter (GM) in BD, none has longitudinally focused on PL anatomy in BD, relating it to patients' functioning. Thirty-eight right-handed BD patients and 42 matched healthy subjects (HS) underwent a Magnetic Resonance Imaging (MRI) scan at baseline. Seventeen BD patients and 16 matched HS underwent a follow-up MRI. PL white matter (WM) and GM volumes were measured. The trajectory of parietal volumes over time and the possible relation with the global functioning were investigated in both BD patients and HS. At baseline, BD patients showed significant reduced PL WM and GM and different WM laterality compared with HS. Furthermore, smaller PL WM volumes predicted lower global functioning in BD, but not in HS. At follow-up, although BD patients reported reduced PL WM compared with HS, no different pattern of volume changes over time was detected between groups. This study suggests the involvement of the PL in the pathophysiology of BD. In particular, PL WM reductions seem to predict an impairment in general functioning in BD and might represent a marker of functional outcome.
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Trastorno Bipolar/patología , Lóbulo Parietal/patología , Adulto , Atención/fisiología , Trastorno Bipolar/diagnóstico por imagen , Trastorno Bipolar/fisiopatología , Estudios de Casos y Controles , Estudios Transversales , Femenino , Lateralidad Funcional , Sustancia Gris/diagnóstico por imagen , Sustancia Gris/patología , Humanos , Estudios Longitudinales , Imagen por Resonancia Magnética/métodos , Masculino , Memoria/fisiología , Persona de Mediana Edad , Tamaño de los Órganos , Lóbulo Parietal/diagnóstico por imagen , Lóbulo Parietal/fisiopatología , Sustancia Blanca/diagnóstico por imagen , Sustancia Blanca/patologíaRESUMEN
Several strands of evidence reported a significant overlapping, in terms of clinical symptoms, epidemiology and treatment response, between the two major psychotic disorders-Schizophrenia (SCZ) and Bipolar Disorder (BD). Nevertheless, the shared neurobiological correlates of these two disorders are far from conclusive. This study aims toward a better understanding of possible common microstructural brain alterations in SCZ and BD. Magnetic Resonance Diffusion data of 33 patients with BD, 19 with SCZ and 35 healthy controls were acquired. Diffusion indexes were calculated, then analyzed using Tract-Based Spatial Statistics (TBSS). We tested correlations with clinical and psychological variables. In both patient groups mean diffusion (MD), volume ratio (VR) and radial diffusivity (RD) showed a significant increase, while fractional anisotropy (FA) and mode (MO) decreased compared to the healthy group. Changes in diffusion were located, for both diseases, in the fronto-temporal and callosal networks. Finally, no significant differences were identified between patient groups, and a significant correlations between length of disease and FA and VR within the corpus callosum, corona radiata and thalamic radiation were observed in bipolar disorder. To our knowledge, this is the first study applying TBSS on all the DTI indexes at the same time in both patient groups showing that they share similar impairments in microstructural connectivity, with particular regards to fronto-temporal and callosal communication, which are likely to worsen over time. Such features may represent neural common underpinnings characterizing major psychoses and confirm the central role of white matter pathology in schizophrenia and bipolar disorder.
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Trastorno Bipolar/patología , Esquizofrenia/patología , Sustancia Blanca/patología , Adulto , Trastorno Bipolar/diagnóstico por imagen , Imagen de Difusión por Resonancia Magnética , Femenino , Humanos , Masculino , Persona de Mediana Edad , Esquizofrenia/diagnóstico por imagenRESUMEN
First episode psychosis (FEP) patients are of particular interest for neuroimaging investigations because of the absence of confounding effects due to medications and chronicity. Nonetheless, imaging data are prone to heterogeneity because for example of age, gender or parameter setting differences. With this work, we wanted to take into account possible nuisance effects of age and gender differences across dataset, not correcting the data as a pre-processing step, but including the effect of nuisance covariates in the classification phase. To this aim, we developed a method which, based on multiple kernel learning (MKL), exploits the effect of these confounding variables with a subject-depending kernel weighting procedure. We applied this method to a dataset of cortical thickness obtained from structural magnetic resonance images (MRI) of 127 FEP patients and 127 healthy controls, who underwent either a 3Tesla (T) or a 1.5T MRI acquisition. We obtained good accuracies, notably better than those obtained with standard SVM or MKL methods, up to more than 80% for frontal and temporal areas. To our best knowledge, this is the largest classification study in FEP population, showing that fronto-temporal cortical thickness can be used as a potential marker to classify patients with psychosis.
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Corteza Cerebral/diagnóstico por imagen , Aprendizaje Automático , Imagen por Resonancia Magnética/métodos , Trastornos Psicóticos/diagnóstico por imagen , Adulto , Femenino , Humanos , Masculino , Máquina de Vectores de Soporte , Adulto JovenRESUMEN
Bipolar disorder (BD) is a major psychiatric illness with a chronic recurrent course, ranked among the worldwide leading disabling diseases. Its pathophysiology is still not completely understood and findings are still inconclusive, though a great interest on the topic has been constantly raised by magnetic resonance imaging, genetic and neuropathological studies. In recent years, diffusion tensor imaging (DTI) investigations have prompted interest in the key role of white matter (WM) abnormalities in BD. In this report, we summarize and comment recent findings from DTI studies in BD, reporting fractional anisotropy as putative measure of WM integrity, as well as recent data from neuropathological studies focusing on oligodendrocyte involvement in WM alterations in BD. DTI research indicates that BD is most commonly associated with a WM disruption within the fronto-limbic network, which may be accompanied by other WM changes spread throughout temporal and parietal regions. Neuropathological studies, mainly focused on the fronto-limbic network, have repeatedly shown a loss in cortical and subcortical oligodendrocyte cell count, although an increased subcortical oligodendrocyte density has been also documented suggesting a putative role in remyelination processes for oligodendrocytes in BD. According to our review, a greater integration between DTI and morphological findings is needed in order to elucidate processes affecting WM, either glial loss or myelin plasticity, on the basis of a more targeted research in BD.
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Agranulocitosis/inducido químicamente , Agranulocitosis/tratamiento farmacológico , Antipsicóticos/efectos adversos , Clozapina/efectos adversos , Factor Estimulante de Colonias de Granulocitos/uso terapéutico , Esquizofrenia Paranoide/tratamiento farmacológico , Adulto , Agranulocitosis/diagnóstico , Humanos , Masculino , Esquizofrenia Paranoide/diagnóstico , Resultado del TratamientoRESUMEN
INTRODUCTION: The rate of biological change in middle-adulthood is relatively under-studied. Here, we used behavioral testing in conjunction with structural magnetic resonance imaging to examine the effects of chronological age on associative learning proficiency and on brain regions that previous functional MRI studies have closely related to the domain of associative learning. METHODS: Participants (n=66) completed a previously established associative learning paradigm, and consented to be scanned using structural magnetic resonance imaging. Age-related effects were investigated both across sub-groups in the sample (younger vs. older) and across the entire sample (using regression approaches). RESULTS: Chronological age had substantial effects on learning proficiency (independent of IQ and Education Level), with older adults showing a decrement compared to younger adults. In addition, decreases in estimated gray matter volume were observed in multiple brain regions including the hippocampus and the dorsal prefrontal cortex, both of which are strongly implicated in associative learning. CONCLUSION: The results suggest that middle adulthood may be a more dynamic period of life-span change than previously believed. The conjunctive application of narrowly focused tasks, with conjointly acquired structural MRI data may allow us to enrich the search for, and the interpretation of, age-related changes in cross-sectional samples.
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Envejecimiento/patología , Envejecimiento/psicología , Aprendizaje por Asociación , Encéfalo/patología , Adulto , Femenino , Sustancia Gris/patología , Humanos , Imagen por Resonancia Magnética , Masculino , Pruebas Neuropsicológicas , Tamaño de los Órganos , Adulto JovenRESUMEN
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.
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Antidepresivos/farmacología , Encéfalo/efectos de los fármacos , Depresión/tratamiento farmacológico , Trastorno Depresivo Mayor/tratamiento farmacológico , Emociones/efectos de los fármacos , Animales , Encéfalo/patología , Depresión/patología , Trastorno Depresivo Mayor/patología , Emociones/fisiología , Humanos , Imagen por Resonancia Magnética/métodosRESUMEN
INTRODUCTION: In recent years the Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology has often been used by international or national health authorities, or scientific societies, for developing evidence-based treatment recommendations. However, the GRADE approach has never been used by practicing physicians who aim at harmonizing their prescribing behaviours paying due attention to the best available evidence. This paper describes the experience of a working group of psychiatrists who adopted the GRADE approach to develop clinical recommendations on the use of psychotropic drugs in specialist mental healthcare. CASE DESCRIPTION: The project was conducted in the Department of Mental Health of Verona, Italy, a city located in the north of Italy. At the beginning of 2012, psychiatrists with a specific interest in the rational use of psychotropic drugs were identified and appointed as members of a Guideline Development Group (GDG). The first task of the GDG was the identification of controversial areas in the use of psychotropic drugs, the definition of scoping questions, and the identification of outcomes of interest. The GDG was supported by a scientific secretariat, who searched the evidence, identified one or more systematic reviews matching the scoping questions, and drafted GRADE tables. DISCUSSION AND EVALUATION: On the basis of efficacy, acceptability, tolerability and safety data, considering the risk of bias and confidence in estimates, and taking also into consideration preferences, values and practical aspects in favour and against the intervention under scrutiny, a draft recommendation with its strength was formulated and agreed by GDG members. Recommendations were submitted for consideration to all specialists of the Department, discussed in two plenary sessions open to the whole staff, and finally approved at the end of 2012. CONCLUSION: The present project of guideline development raised several challenging and innovating aspects, including a "bottom-up" approach, as it was motivated by reasons that found agreement among specialists, those who developed the recommendations were those who were supposed to follow them, and values, preferences and feasibility issues were considered paying due attention to local context variables.
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Genetic, neuropathological and magnetic resonance imaging findings support the presence of diffuse white matter cytoarchitectural disruption in bipolar disorder. In this study, diffusion-weighted imaging (DWI) was applied to study cortical white matter microstructure organisation in 24 patients with DSM-IV bipolar disorder and 35 matched normal controls. DWI images were obtained using a 1.5 Tesla scanner and apparent diffusion coefficient (ADC) values were determined over regions of interest placed, bilaterally, in the frontal, temporal, parietal, and occipital white matter. Significantly increased ADC values were found in bipolar patients with respect to normal controls in the right temporal lobe, left parietal lobe and bilateral occipital lobes. ADC values did not associate significantly with age or with clinical variables (p>0.05). Diffuse cortical white matter alterations on DWI in bipolar disorder denote widespread disruption of white matter integrity and may be due to altered myelination and/or axonal integrity.
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Trastorno Bipolar/patología , Corteza Cerebral/patología , Imagen de Difusión por Resonancia Magnética , Leucoencefalopatías/patología , Fibras Nerviosas Mielínicas/patología , Adulto , Femenino , Humanos , Masculino , Persona de Mediana EdadRESUMEN
Schizophrenia is a disease with heterogeneous features and often a disabling longitudinal outcome. In order to achieve a better understanding of the disease, a detailed characterization and definition of symptomatology, social functioning and cognitive performance of patients is required. Imaging techniques may allow to identify measurable markers of different subgroups of patients, who share common clinical course and, probably, a similar hereditary pathway. The review offers a description of cross-sectional, predictive and longitudinal studies on the relationship between biological, clinical and psychosocial features of patients with schizophrenia. Patients with a more severe and disabling course of illness present larger ventricles, smaller prefrontal, temporal and occipital cortices and smaller subcortical regions such as basal ganglia, the thalamus and limbic areas. These alterations are predictive of a worse prognosis, as observed in predictive and longitudinal studies, both on chronic and first episode patients. The detection of more homogenous groups of patients with schizophrenia will help neurobiological research progress in this field. Furthermore, patients with similar clinical and biological features could undergo more tailored therapeutic and rehabilitative strategies.
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Neuroimagen , Esquizofrenia/diagnóstico , Ganglios Basales/patología , Ventrículos Cerebrales/patología , Medicina Basada en la Evidencia , Humanos , Sistema Límbico/patología , Angiografía por Resonancia Magnética , Imagen por Resonancia Magnética/métodos , Neuroimagen/métodos , Neurorradiografía , Lóbulo Occipital/patología , Tomografía de Emisión de Positrones/métodos , Corteza Prefrontal/patología , Pronóstico , Esquizofrenia/diagnóstico por imagen , Esquizofrenia/etiología , Lóbulo Temporal/patología , Tálamo/patología , Tomógrafos Computarizados por Rayos XRESUMEN
Ventricular enlargement is one of the most consistent abnormal structural brain findings in schizophrenia and has been used to infer brain shrinkage. However, whether ventricular enlargement is related to local overlying cortex and/or adjacent subcortical structures or whether it is related to brain volume change globally has not been assessed. We systematically assessed interrelations of ventricular volumes with gray and white matter volumes of 40 Brodmann areas (BAs), the thalamus and its medial dorsal nucleus and pulvinar, the internal capsule, caudate and putamen. We acquired structural MRI ( patients with schizophrenia (n = 64) and healthy controls (n = 56)) and diffusion tensor fractional anisotropy (FA) (untreated schizophrenia n = 19, controls n = 32). Volumes were assessed by manual tracing of central structures and a semi-automated parcellation of BAs. Patients with schizophrenia had increased ventricular size associated with decreased cortical gray matter volumes widely across the brain; a similar but less pronounced pattern was seen in normal controls; local correlations (e.g. temporal horn with temporal lobe volume) were not appreciably higher than non-local correlations (e.g. temporal horn with prefrontal volume). White matter regions adjacent to the ventricles similarly did not reveal strong regional relationships. FA and center of mass of the anterior limb of the internal capsule also appeared differentially influenced by ventricular volume but findings were similarly not regional. Taken together, these findings indicate that ventricular enlargement is globally interrelated with gray matter volume diminution but not directly correlated with volume loss in the immediately adjacent caudate, putamen, or internal capsule.