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A ressonância magnética funcional (RMF) é uma nova técnica capaz de detectar pequenas alterações no fluxo sanguíneo e oxigenação de tecidos cerebrais em que ocorre ativação neuronal. O seu emprego na avaliação pré-cirúrgica de pacientes com epilepsia portadores de esclerose mesial temporal está atualmente em avaliação em alguns centros de neurologia. O principal objetivo é encontrar o melhor paradigma de ativação na avaliação das funções de linguagem e memória, visando a substituição do teste de Wada, largamente utilizado nos dias de hoje. Para formular um paradigma já adaptado ao nosso idioma, apresentamos a nossa experiência em uma tarefa comportamental de fluência verbal na determinação da lateralização da área cerebral da linguagem. Avaliaram-se os exames de RMF de uma clínica de imagem particular em Curitiba por período de aproximadamente dois anos. Dos 19 pacientes estudados, obteve-se sucesso no exame em 16 e, destes, todos apresentavam dominância hemisférica cerebral da linguagem à esquerda. Em um subgrupo com 5 pacientes foi possível comparar os resultados obtidos com a técnica de Wada e RMF, havendo concordância entre as técnicas. A partir deste estudo e de vários outros semelhantes na literatura, acreditamos que a RMF está progressivamente conquistando seu espaço na prática médica.

An extensive survey of the D2 absorption spectrum has been performed with the high-resolution VUV Fourier-transform spectrometer employing synchrotron radiation. The frequency range of 90 000-119 000 cm-1 covers the full depth of the potential wells of the B 1Σu+, B′ 1Σu+, and C 1Πu electronic states up to the D(1s) + D(2ℓ) dissociation limit. Improved level energies of rovibrational levels have been determined up to respectively v = 51, v = 13, and v = 20. Highest resolution is achieved by probing absorption in a molecular gas jet with slit geometry, as well as in a liquid helium cooled static gas cell, resulting in line widths of ≈0.35 cm-1. Extended calibration methods are employed to extract line positions of D2 lines at absolute accuracies of 0.03 cm-1. The D 1Πu and B′′ 1Σu+ electronic states correlate with the D(1s) + D(3ℓ) dissociation limit, but support a few vibrational levels below the second dissociation limit, respectively, v = 0-3 and v = 0-1, and are also included in the presented study. The complete set of resulting level energies is the most comprehensive and accurate data set for D2. The observations are compared with previous studies, both experimental and theoretical. [ABSTRACT FROM AUTHOR]

Functional magnetic resonance imaging (fMRI) is a technique for detecting minimal changes in brain perfusion and oxygenation secondary to neuronal activation. Its application in the pre-surgical evaluation of epileptic patients with temporal mesial sclerosis is currently being under investigation in several centers. This study aims to describe an activation paradigm for the evaluation of language and memory functions, as an alternative to the worldwide used Wada test, which is an invasive procedure. In order to propose a paradigm adapted to the Portuguese language, we report our experience in determining the dominant cerebral area for language through fMRI with a verbal fluency task. The results of the fMRI from 19 patients studied in Curitiba in a period of approximately two years were studied. Sixteen of them presented with left hemispheric cerebral language dominance. In five patients, results from fMRI and Wada test could be compared and agreed in localization. Our results reinforce the view that fMRI may become an essential tool for medical practice, perhaps for the determination of eloquent areas in the evaluation of candidates for epilepsy surgery.