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Quiroz Y.T.,Boston University | Quiroz Y.T.,University of Antioquia | Budson A.E.,Boston University | Budson A.E.,Center for Translational Cognitive Neuroscience | And 6 more authors.
Annals of Neurology | Year: 2010

Objective: The examination of individuals who carry fully penetrant genetic alterations that result in familial Alzheimer's disease (FAD) provides a unique model for studying the early presymptomatic disease stages. In AD, deficits in episodic and associative memory have been linked to structural and functional changes within the hippocampal system. This study used functional MRI (fMRI) to examine hippocampal function in a group of healthy, young, cognitively-intact presymptomatic individuals (average age 33.7 years) who carry the E280A presenilin-1 (PS1) genetic mutation for FAD. These PS1 subjects will go on to develop the first symptoms of the disease around the age of 45 years. Our objective was to examine hippocampal function years before the onset of clinical symptoms. Methods Twenty carriers of the Alzheimer's-associated E280A PS1 mutation and 19 PS1-negative control subjects participated. Both groups were matched for age, sex, education level, and neuropsychological test performance. All participants performed a face-name associative encoding task while in a Phillips 1.5T fMRI scanner. Analysis focused on the hippocampal system. Results Despite identical behavioral performance, presymptomatic PS1 mutation carriers exhibited increased activation of the right anterior hippocampus during encoding of novel face-name associations compared to matched controls. Interpretation Our results demonstrate that functional changes within the hippocampal memory system occur years before cognitive decline in FAD. These presymptomatic changes in hippocampal physiology in FAD suggest that hippocampal fMRI patterns during associative encoding may also provide a preclinical biomarker in sporadic AD. Copyright © 2010 American Neurological Association. Source


Quiroz Y.T.,University of Antioquia | Quiroz Y.T.,Massachusetts General Hospital | Willment K.C.,Brigham and Womens Hospital | Castrillon G.,Institute Alta Tecnologia Medica IATM | And 5 more authors.
Journal of Alzheimer's Disease | Year: 2015

Background: Brain regions critical to episodic memory are altered during the preclinical stages of Alzheimer's disease (AD). However, reliable means of identifying cognitively-normal individuals at higher risk to develop AD have not been established. Objective: To examine whether functional MRI can detect early functional changes associated with scene encoding in a group of presymptomatic presenilin-1 (PSEN1) E280A mutation carriers. Methods: Participants were 39 young, cognitively-normal individuals from an autosomal dominant early-onset AD kindred, located in Antioquia, Colombia. Participants performed a functional MRI scene encoding task and a post-scan subsequent memory test. Results: PSEN1 mutation carriers exhibited hyperactivation within medial temporal lobe regions (hippocampus, parahippocampal formation) during successful scene encoding compared to age-matched non-carriers. Conclusion: Hyperactivation in medial temporal lobe regions during scene encoding is seen in individuals genetically-determined to develop AD years before their clinical onset. Our findings will guide future research with the ultimate goal of using functional neuroimaging in the early detection of preclinical AD. © 2015 - IOS Press and the authors. All rights reserved. Source


Ladino L.D.,University of Antioquia | Ladino L.D.,Institute Alta Tecnologia Medica IATM | Delgado De Bedout J.A.,Institute Alta Tecnologia Medica IATM | Lopez Rios A.L.,Hospital Universitario San Vicente Fundacion | Arango Viana J.C.,University of Antioquia
Neurologia Argentina | Year: 2013

Background: The jugular paraganglioma is a rare tumor of head and neck. Case report: 34 year old woman with a long standing jugular paraganglioma with extracranial and intracranial component that occupies much of the posterior fossa, this compress the stem and the cerebellum, we conducted a clinical, imaging and histopathologic correlation. The identification of the tumor showed typical findings in salt and pepper on both magnetic resonance sequences and histological sections. Conclusions: The jugular paraganglioma is histologically a benign tumor, but its progressive growth, may compromise important intracranial structures. © 2012 Sociedad Neurológica Argentina. Published by Elsevier España, S.L. All rights reserved. Source


Pineda Zapata J.A.,Institute Alta Tecnologia Medica IATM | Delgado De Bedout J.A.,Institute Alta Tecnologia Medica IATM | Rascovsky Ramirez S.,Institute Alta Tecnologia Medica IATM | Bustamante C.,Institute Alta Tecnologia Medica IATM | And 2 more authors.
Radiologia | Year: 2014

The 4D Flow MRI technique provides a three-dimensional representation of blood flow over time, making it possible to evaluate the hemodynamics of the cardiovascular system both qualitatively and quantitatively. In this article, we describe the application of the 4D Flow technique in a 3 T scanner; in addition to the technical parameters, we discuss the advantages and limitations of the technique and its possible clinical applications. We used 4D Flow MRI to study different body areas (chest, abdomen, neck, and head) in 10 volunteers. We obtained 3D representations of the patterns of flow and quantitative hemodynamic measurements. The technique makes it possible to evaluate the pattern of blood flow in large and midsize vessels without the need for exogenous contrast agents. © 2013 SERAM. Published by Elsevier España, S.L.U. All rights reserved. Source


Vargas C.,University of Antioquia | Pineda J.,University of Antioquia | Pineda J.,Institute Alta Tecnologia Medica IATM | Calvo V.,University of Antioquia | And 3 more authors.
Revista Colombiana de Psiquiatria | Year: 2014

Introduction As there are still doubts about brain connectivity in type I bipolar disorder (BID), resting-state functional magnetic resonance imaging (RS-fMRI) studies are necessary during euthymia for a better control of confounding factors. Objective To evaluate the differences in brain activation between euthymic BID patients and control subjects using resting state- functional-magnetic resonance imaging (RS-fMRI), and to identify the lithium effect in these activations. Methods A cross-sectional study was conducted on 21 BID patients (10 receiving lithium only, and 11 non-medicated) and 12 healthy control subjects, using RS fMRI and independent component analysis (ICA). Results Increased activation was found in the right hippocampus (P =.049) and posterior cingulate (P =.040) within the Default Mode Network (DMN) when BID and control group were compared. No statistically significant differences were identified between BID on lithium only therapy and non-medicated BID patients. Conclusions The results suggest that there are changes in brain activation and connectivity in BID even during euthymic phase and mainly within the DMN network, which could be relevant in affect regulation. © 2013 Asociacion Colombiana de Psiquiatria. Publicado por Elsevier Espana, S.L.U. Todoslos derechos reservados. Source

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