BackgroundMesial temporal lobe epilepsy (MTLE), the most common type of focal epilepsy in adults, is often caused by hippocampal sclerosis (HS). Patients with HS usually present memory dysfunction, which is material-specific according to the hemisphere involved and has been correlated to the degree of HS as measured by postoperative histopathology as well as by the degree of hippocampal atrophy on magnetic resonance imaging (MRI). Verbal memory is mostly affected by left-sided HS, whereas visuo-spatial memory is more affected by right HS. Some of these impairments may be related to abnormalities of the network in which individual hippocampus takes part. Functional connectivity can play an important role to understand how the hippocampi interact with other brain areas. It can be estimated via functional Magnetic Resonance Imaging (fMRI) resting state experiments by evaluating patterns of functional networks. In this study, we investigated the functional connectivity patterns of 9 control subjects, 9 patients with right MTLE and 9 patients with left MTLE.ResultsWe detected differences in functional connectivity within and between hippocampi in patients with unilateral MTLE associated with ipsilateral HS by resting state fMRI. Functional connectivity resulted to be more impaired ipsilateral to the seizure focus in both patient groups when compared to control subjects. This effect was even more pronounced for the left MTLE group.ConclusionsThe findings presented here suggest that left HS causes more reduction of functional connectivity than right HS in subjects with left hemisphere dominance for language.

Neuropsychiatric syndromes are highly prevalent in Alzheimer's disease (AD), but their neurobiology is not completely understood. New methods in functional magnetic resonance imaging, such as intrinsic functional connectivity or "resting-state" analysis, may help to clarify this issue. Using such approaches, alterations in the default-mode and salience networks (SNs) have been described in Alzheimer's, although their relationship with specific symptoms remains unclear. We therefore carried out resting-state functional connectivity analysis with 20 patients with mild to moderate AD, and correlated their scores on neuropsychiatric inventory syndromes (apathy, hyperactivity, affective syndrome, and psychosis) with maps of connectivity in the default mode network and SN. In addition, we compared network connectivity in these patients with that in 17 healthy elderly control subjects. All analyses were controlled for gray matter density and other potential confounds. Alzheimer's patients showed increased functional connectivity within the SN compared with controls (right anterior cingulate cortex and left medial frontal gyrus), along with reduced functional connectivity in the default-mode network (bilateral precuneus). A correlation between increased connectivity in anterior cingulate cortex and right insula areas of the SN and hyperactivity syndrome (agitation, irritability, aberrant motor behavior, euphoria, and disinhibition) was found. These findings demonstrate an association between specific network changes in AD and particular neuropsychiatric symptom types. This underlines the potential clinical significance of resting state alterations in future diagnosis and therapy.

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RESUMO -As heterogeneidades educacional e cultural da população brasileira condicionam características p e c u l i a res ao diagnóstico da doença de Alzheimer (DA) no Brasil. Este consenso teve o objetivo de recomendar condutas baseadas em evidências para este diagnóstico. Foram avaliados sistematicamente artigos sobre o diagnóstico de DA no Brasil disponíveis no PUBMED ou LILACS. Para a avaliação cognitiva global recomendou-se o Mini-Exame do Estado Mental; avaliação da memória: re c o rdação tardia do CERAD ou de objetos apresentados como figuras; atenção: teste de trilhas ou extensão de dígitos; linguagem: testes de nomeação de Boston, do ADAS-Cog ou do NEUROPSI; funções executivas: fluência verbal ou desenho do relógio; conceituação e abstração: semelhanças do CAMDEX ou do NEUROPSI; habilidades construtivas: desenhos do CERAD. Para avaliação funcional recomendou-se o IQCODE , o questionário de P f e ffer ou a escala Bayer de atividades da vida diária. Recomendou-se a utilização combinada de instru m e n t o s de avaliação cognitiva e de escalas de avaliação funcional. PALAVRAS-CHAVE: consenso, diretrizes, normas, diagnóstico, doença de Alzheimer, demência, Brasil.Diagnosis of Alzheimer's disease in Brazil: cognitive and functional evaluation. Recommendations of the Scientifc Department of Cognitive Neurology and Aging of the Brazilian Academy of Neurology ABSTRACT -The educational and cultural heterogeneity of the Brazilian population leads to peculiar characteristics re g a rding the diagnosis of Alzheimer's disease (AD). This consensus had the objective of recommending evidence-based guidelines for the clinical diagnosis of AD in Brazil. Studies on the diagnosis of AD published in Brazil were systematically evaluated in a thorough re s e a rch of PUBMED and LILACS databases. For global cognitive evaluation, the Mini-Mental State Examination was recommended; for m e m o ry evaluation: delayed recall subtest of CERAD or of objects presented as drawings; attention: trailmaking or digit-span; language: Boston naming, naming test from ADAS-Cog or NEUROPSI; executive functions: verbal fluency or clock-drawing; conceptualization and abstraction: similarities from CAMDEX or NEUROPSI; construction: drawings from CERAD. For functional evaluation, IQCODE, or Pfeff e r Q u e s t i o n n a i reor Bayer Scale for Activities of Daily Living was recommended. The panel concluded that the combined use of cognitive and functional evaluation based on interview with informant is re c o m m e n d e d .

BACKGROUND AND PURPOSE:TA is a branch of image processing that seeks to reduce image information by extracting texture descriptors from the image. TA of MR images of anatomic structures in mild AD and aMCI is not well-studied. Our objective was to attempt to find differences among patients with aMCI and mild AD and normal-aging subjects, by using TA applied to the MR images of the CC and the thalami of these groups of subjects.