NEUROIMÁGENES EN DEMENCIAS

Las demencias constituyen un problema severo de salud a nivel mundial, y describen una gran cantidad de síntomas. Se caracterizan por un deterioro cognitivo adquirido irreversible que afecta principalmente, pero no exclusivamente, la memoria. Además, afecta especialmente a las personas mayores, pero no constituye una consecuencia normal del envejecimiento. Existen múltiples técnicas imagenológicas que apoyan el diagnóstico, que están en etapa de investigación o que se utilizan actualmente en el aspecto clínico. Protocolos estándar de imágenes de resonancia magnética, escalas de evaluación visual de la atrofia, técnicas de volumetría cerebral, paradigmas de resonancia magnética funcional, técnicas de conectividad funcional de reposo, SPECT y PET son las técnicas que se comentarán en este artículo

An action-concept processing advantage in a patient with a double motor cortex

Patients with atrophy in motor brain regions exhibit selective deficits in processing action-related meanings, suggesting a link between movement conceptualization and the amount of regional tissue. Here we examine such a relation in a unique opposite model: a rare patient with a double cortex (due to subcortical band heterotopia) in primary/supplementary motor regions, and no double cortex in multimodal semantic regions. We measured behavioral performance in action- and object-concept processing as well and resting-state functional connectivity. Both dimensions involved comparisons with healthy controls. Results revealed preserved accuracy in action and object categories for the patient. However, unlike controls, the patient exhibited faster performance for action than object concepts, a difference that was uninfluenced by general cognitive abilities. Moreover, this pattern was accompanied by heightened functional connectivity between the bilateral primary motor cortices. This suggests that a functionally active double motor cortex may entail action-processing advantages. Our findings offer new constraints for models of action semantics and motor-region function at large.Fil: Miranda, Magdalena. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Neurociencia Cognitiva y Traslacional. Fundación Ineco Rosario Sede del Incyt | Instituto de Neurología Cognitiva. Instituto de Neurociencia Cognitiva y Traslacional. Fundación Ineco Rosario Sede del Incyt | Fundación Favaloro. Instituto de Neurociencia Cognitiva y Traslacional. Fundación Ineco Rosario Sede del Incyt; ArgentinaFil: Gonzalez Campo, Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de San Andrés; ArgentinaFil: Birba, Agustina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de San Andrés; Argentina. Universidad Adolfo Ibañez; ChileFil: Neely, Alejandra. Universidad Adolfo Ibañez; ChileFil: Toro Hernandez, Felipe. Universidad Adolfo Ibañez; Chile. Universidad Federal do Abc; BrasilFil: Faure, Evelyng. Clínica Las Condes; ChileFil: Rojas Costa, Gonzalo. Clínica Las Condes; ChileFil: Ibañez, Agustin Mariano. Universidad de San Andrés; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Adolfo Ibañez; ChileFil: García, Adolfo Martín. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de San Andrés; Argentina. Universidad Nacional de Cuyo. Facultad de Educación Elemental y Especial; Argentina. Universidad de Santiago de Chile; Chil

Visual analysis of automated segmentation in the diagnosis of focal cortical dysplasias with magnetic resonance imaging

[EN] Focal cortical dysplasias (FCDs) are a frequent cause of epilepsy. It has been reported that up to 40% of them cannot be visualized with conventional magnetic resonance imaging (MRI). The main objective of this work was to evaluate by means of a retrospective descriptive observational study whether the automated brain segmentation is useful for detecting FCD. One hundred and fifty-five patients, who underwent surgery between the years 2009 and 2016, were reviewed. Twenty patients with FCD confirmed by histology and a preoperative segmentation study, with ages ranging from 3 to 43 years (14 men), were analyzed. Three expert neuroradiologists visually analyzed conventional and advancedMRI with automated segmentation. They were classified into positive and negative concerning visualization of FCD by consensus. Of the 20 patients evaluated with conventional MRI, 12 were positive for FCD.Of the negative studies for FCD with conventional MRI, 2 (25%) were positive when they were analyzed with automated segmentation. In 13 of the 20 patients (with positive segmentation for FCD), cortical thickening was observed in 5 (38.5%), while pseudo thickening was observed in the rest of patients (8, 61.5%) in the anatomical region of the brain corresponding to the dysplasia. This work demonstrated that automated brain segmentation helps to increase detection of FCDs that are unable to be visualized in conventional MRI images.Sepúlveda, MM.; Rojas, GM.; Faure, E.; Pardo, CR.; Las Heras, F.; Okuma, C.; Cordovez, J.... (2020). Visual analysis of automated segmentation in the diagnosis of focal cortical dysplasias with magnetic resonance imaging. Epilepsy & Behavior. 102:1-10. https://doi.org/10.1016/j.yebeh.2019.106684S110102Fisher, R. 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