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OBJECTIVE: To characterize cerebral microbleeds (CMBs) in lacunar stroke patients in the Secondary Prevention of Small Subcortical Strokes (SPS3) trial and to assess their relationship with recurrent stroke and death, and response to assigned treatment. METHODS: SPS3 is a randomized, clinical trial conducted between 2003 and 2011. Patients with recent magnetic resonance imaging (MRI)-documented lacunar infarcts were randomly assigned in a factorial design to target levels of systolic blood pressure (130-149mmHg vs <130mmHg; open label) and to antiplatelet treatment (aspirin/clopidogrel vs aspirin/placebo; double-blinded). The current analysis involves 1,278 trial participants who had a baseline axial T2*-weighted gradient echo MRI sequence allowing for CMB detection. RESULTS: CMBs were present in 30% of 1,278 patients (mean age = 63 years). Male gender (odds ratio [OR] = 1.7, 95% confidence interval [CI] = 1.3-2.3), history of hypertension (OR = 1.6, 95% CI = 1.2-2.3), increased systolic blood pressure (1.2 per 20mmHg, 95% CI = 1.1-1.4), nondiabetic status (OR = 1.4, 95% CI = 1.1-1.9), multiple old lacunar infarcts (OR = 1.9, 95% CI = 1.5-2.5), and moderate (OR = 1.7, 95% CI = 1.2-2.3) or severe (OR = 4.2, 95% CI = 3.0-5.9) white matter hyperintensities on MRI were independently associated with CMBs. During a mean follow-up of 3.3 years, overall stroke recurrence was 2.5% per patient-year. Patients with CMBs had an adjusted 2-fold increased risk of recurrent stroke (hazard ratio = 2.1, 95% CI = 1.4-3.1). CMBs were not a risk factor for death. There were no statistically significant interactions between CMBs and treatment assignments. INTERPRETATION: Patients with lacunar stroke and CMBs likely harbor a more advanced form of cerebral small vessel disease in need of efficacious therapeutic strategies. Ann Neurol 2017;82:196-207.
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Aspirina/uso terapéutico , Hemorragia Cerebral/mortalidad , Hemorragia Cerebral/prevención & control , Prevención Secundaria/métodos , Accidente Vascular Cerebral Lacunar/prevención & control , Ticlopidina/análogos & derivados , Hemorragia Cerebral/complicaciones , Clopidogrel , Método Doble Ciego , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Inhibidores de Agregación Plaquetaria/uso terapéutico , Recurrencia , Factores de Riesgo , Accidente Vascular Cerebral Lacunar/complicaciones , Accidente Vascular Cerebral Lacunar/diagnóstico por imagen , Ticlopidina/uso terapéuticoRESUMEN
PURPOSE: To apply resting-state functional magnetic resonance (MR) imaging to map functional connectivity of the human spinal cord. MATERIALS AND METHODS: Studies were performed in nine self-declared healthy volunteers with informed consent and institutional review board approval. Resting-state functional MR imaging was performed to map functional connectivity of the human cervical spinal cord from C1 to C4 at 1 × 1 × 3-mm resolution with a 3.0-T clinical MR imaging unit. Independent component analysis (ICA) was performed to derive resting-state functional MR imaging z-score maps rendered on two-dimensional and three-dimensional images. Seed-based analysis was performed for cross validation with ICA networks by using Pearson correlation. RESULTS: Reproducibility analysis of resting-state functional MR imaging maps from four repeated trials in a single participant yielded a mean z score of 6 ± 1 (P < .0001). The centroid coordinates across the four trials deviated by 2 in-plane voxels ± 2 mm (standard deviation) and up to one adjacent image section ± 3 mm. ICA of group resting-state functional MR imaging data revealed prominent functional connectivity patterns within the spinal cord gray matter. There were statistically significant (z score > 3, P < .001) bilateral, unilateral, and intersegmental correlations in the ventral horns, dorsal horns, and central spinal cord gray matter. Three-dimensional surface rendering provided visualization of these components along the length of the spinal cord. Seed-based analysis showed that many ICA components exhibited strong and significant (P < .05) correlations, corroborating the ICA results. Resting-state functional MR imaging connectivity networks are qualitatively consistent with known neuroanatomic and functional structures in the spinal cord. CONCLUSION: Resting-state functional MR imaging of the human cervical spinal cord with a 3.0-T clinical MR imaging unit and standard MR imaging protocols and hardware reveals prominent functional connectivity patterns within the spinal cord gray matter, consistent with known functional and anatomic layouts of the spinal cord.
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Imagen por Resonancia Magnética/métodos , Médula Espinal/fisiología , Adulto , Femenino , Voluntarios Sanos , Humanos , Imagenología Tridimensional , MasculinoRESUMEN
BACKGROUND: The clinical implications of vertebrobasilar ectasia (VBE) in patients with cerebral small-artery disease are not well defined. We investigated whether VBE is associated with recurrent stroke, major hemorrhage, and death in a large cohort of patients with recent lacunar stroke. METHODS: Maximum diameters of the vertebral and basilar arteries were measured by magnetic resonance angiography and computed tomographic angiography in 2621 participants in the Secondary Prevention of Small Subcortical Strokes trial. VBE was defined a priori as basilar artery greater than 4.5 mm and/or vertebral artery greater than 4.0 mm. Patient characteristics and risks of stroke recurrence and mortality during follow-up (median, 3.5 years) were compared between patients with and without VBE. RESULTS: VBE affecting 1 or more arteries was present in 200 (7.6%) patients. Patient features independently associated with VBE were increasing age, male sex, white race ethnicity, hypertension, and higher baseline diastolic blood pressure. Baseline systolic blood pressure was inversely associated with VBE. After adjustment for other risk factors, VBE was not predictive of recurrent stroke (hazard ratio [HR], 1.3; 95% confidence interval [CI], .85-1.9) or major hemorrhage (HR, 1.5; CI, .94-2.6), but was of death (HR, 1.7; CI, 1.1-2.7). CONCLUSIONS: In this large well-characterized cohort of patients with recent lacunar stroke, VBE was predictive of death but not of recurrent stroke or major hemorrhage. In these exploratory analyses, the frequency of VBE was directly related to diastolic blood pressure but inversely related to systolic blood pressure.
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Arteria Basilar/patología , Dilatación Patológica/etiología , Inhibidores de Agregación Plaquetaria/uso terapéutico , Accidente Vascular Cerebral Lacunar/complicaciones , Accidente Vascular Cerebral Lacunar/prevención & control , Anciano , Clopidogrel , Método Doble Ciego , Femenino , Humanos , Angiografía por Resonancia Magnética , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Prevención Secundaria , Estadísticas no Paramétricas , Ticlopidina/análogos & derivados , Ticlopidina/uso terapéutico , Tomógrafos Computarizados por Rayos XRESUMEN
BACKGROUND AND PURPOSE: Diabetes mellitus is an independent risk factor for lacunar strokes. Few data are available regarding patient features, infarct location, and recurrent vascular events for patients with diabetes mellitus with lacunar stroke. METHODS: We compared features at study entry and prognosis during 3.6 years of follow-up of patients with diabetes mellitus versus patients without diabetes mellitus with recent lacunar stroke participating in the Secondary Prevention of Small Subcortical Strokes (SPS3) randomized trial. RESULTS: Among the 3020 participants, the prevalence of diabetes mellitus was 37% with a mean duration of 11 years. Diabetes mellitus was independently associated with slightly younger age (63 versus 64 years; P<0.001), Hispanic ethnicity (36% versus 28%; P<0.0001), ischemic heart disease (11% versus 6%; P=0.002), and peripheral vascular disease (5% versus 2%; P<0.001). Patients with diabetes mellitus more frequently had intracranial stenosis ≥50% (P<0.001), infarcts involving the brain stem or cerebellum (P<0.001), and more extensive white matter abnormalities (P<0.001). Patients with diabetes mellitus were almost twice as likely to have a recurrent stroke (hazard ratio [HR], 1.8; 95% confidence interval [CI], 1.4-2.3), recurrent ischemic stroke (HR, 1.8; 95% CI, 1.4-2.4), disabling/fatal stroke (HR, 1.8; 95% CI, 1.2-2.9), myocardial infarction (HR, 1.7; 95% CI, 1.0-2.8), and death (HR, 2.1 95% CI, 1.6-2.8) compared with patients without diabetes mellitus. CONCLUSIONS: Patients with diabetes mellitus with lacunar stroke have a distinctive clinical profile that includes double the prevalence of systemic and intracranial atherosclerosis, preferential involvement of the posterior circulation, and a poor prognosis for recurrent stroke and death. CLINICAL TRIAL REGISTRATION URL: http://www.clinicaltrials.gov. Unique identifier: NCT00059306.
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Complicaciones de la Diabetes/epidemiología , Accidente Vascular Cerebral Lacunar/epidemiología , Anciano , Femenino , Estudios de Seguimiento , Humanos , Arteriosclerosis Intracraneal/fisiopatología , Masculino , Persona de Mediana Edad , Prevalencia , Pronóstico , Recurrencia , Factores de Riesgo , Prevención Secundaria , Factores de Tiempo , Resultado del TratamientoRESUMEN
BACKGROUND AND PURPOSE: Infarct size and location are thought to correlate with different mechanisms of lacunar infarcts. We examined the relationship between the size and shape of lacunar infarcts and vascular risk factors and outcomes. METHODS: We studied 1679 participants in the Secondary Prevention of Small Subcortical Stroke trial with a lacunar infarct visualized on diffusion-weighted imaging. Infarct volume was measured planimetrically, and shape was classified based on visual analysis after 3-dimensional reconstruction of axial MRI slices. RESULTS: Infarct shape was ovoid/spheroid in 63%, slab in 12%, stick in 7%, and multicomponent in 17%. Median infarct volume was smallest in ovoid/spheroid relative to other shapes: 0.46, 0.65, 0.54, and 0.90 mL, respectively (P<0.001). Distributions of vascular risk factors were similar across the 4 groups except that patients in the ovoid/spheroid and stick groups were more often diabetic and those with multicomponent had significantly higher blood pressure at study entry. Intracranial stenosis did not differ among groups (P=0.2). Infarct volume was not associated with vascular risk factors. Increased volume was associated with worse functional status at baseline and 3 months. Overall, 162 recurrent strokes occurred during an average of 3.4 years of follow-up with no difference in recurrent ischemic stroke rate by shape or volume. CONCLUSIONS: In patients with recent lacunar stroke, vascular risk factor profile was similar among the different infarct shapes and sizes. Infarct size correlated with worse short-term functional outcome. Neither shape nor volume was predictive of stroke recurrence. CLINICAL TRIAL REGISTRATION URL: http://www.clinicaltrials.gov. Unique identifier: NCT00059306.
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Infarto Cerebral/patología , Accidente Vascular Cerebral Lacunar/patología , Anciano , Infarto Cerebral/complicaciones , Imagen de Difusión por Resonancia Magnética , Femenino , Humanos , Interpretación de Imagen Asistida por Computador , Masculino , Persona de Mediana Edad , Inhibidores de Agregación Plaquetaria/administración & dosificación , Recuperación de la Función , Recurrencia , Prevención Secundaria , Accidente Vascular Cerebral Lacunar/prevención & controlRESUMEN
This study analyzed the critical factors to approach the emergency online teaching due to the COVID-19 pandemic in a business school in Latin America. The data were collected through a semi-structured online questionnaire administered to 94 full-time and part-time faculty members. The study identified 10 critical factors for the successful implementation of emergency online teaching. The originality of the study lies in analyzing the experience in migrating to online teaching in a Hispanic higher education academic institution.
Este estudio analizó los factores críticos necesarios para responder a la urgencia de implementar la enseñanza a distancia debido a la pandemia de COVID-19 en una escuela de negocios en América Latina. La información fue obtenida a través de un cuestionario semi-estructurado administrado en línea a 94 profesores de tiempo completo y tiempo parcial. El estudio identificó 10 factores críticos para la implementación exitosa de la enseñanza a distancia. La originalidad del estudio está en el análisis de la experiencia de transición al aprendizaje a distancia en línea en una institución hispana de educación superior.
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This study evaluated the application and efficiency of modified activated carbon in the removal of copper (Cu) from synthetic aquatic samples. The surface of activated carbon derived from orange peel (AC-OP) and date seeds (AC-DS) have been modified by Titanium dioxide nanoparticles (TiO2 NPs) (1:10 wt% mixing ratio) and used in a series of experiments designed by Response Surface Methodology (RSM) incorporating Central Composite Design (CCD). The Brunauer-Emmett-Teller (BET) test demonstrated that the modification has increased the surface area of AC-OP from 2.40 to 6.06 m2 g-1 and AC-DS from 51.10 to 81.37 m2 g-1. Effects of pH (1-7), ion initial concentration (10-60 mg L-1), adsorbent dose (0.5-8 g L-1), and contact time (0.4-6 h) have been investigated. The results showed that the optimum conditions for TiO2-modified AC-OP (OP-TiO2) are pH 5, initial concentration of 24.6 mg L-1, adsorbent dose of 4.9 g L-1, and contact time of 3.6 h. The optimum conditions for TiO2-modified AC-DS (DS-TiO2) are pH 6.4, initial concentration of 21.2 mg L-1, adsorbent dose of 5 g L-1, and contact time of 3.0 h. The modified quadratic models represented the results well with regression coefficients of 0.91 and 0.99 for OP-TiO2 and DS-TiO2, respectively. The maximum Cu removal for OP-TiO2 and DS-TiO2 were 99.90 % and 97.40 %, and the maximum adsorption capacity was found to be 13.34 and 13.96 mg g-1, respectively. Kinetic data have been fitted to pseudo first-order, pseudo second-order, intra-particle diffusion, and Elovich models. The pseudo second-order showed a better fit to the experimental data (R2 > 98 %). This study demonstrates the successful development of modified activated carbon derived from orange peels and date seeds, modified by TiO2 nanoparticles, for efficient adsorption of copper ions from water. The findings contribute to understanding the adsorption mechanism and provide valuable insights for designing environmentally friendly adsorbents.
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Background: The cerebrospinal fluid filling the ventricles of the brain moves with a cyclic velocity driven by the transmantle pressure, or instantaneous pressure difference between the lateral ventricles and the cerebral subarachnoid space. This dynamic phenomenon is of particular interest for understanding ventriculomegaly in cases of normal pressure hydrocephalus (NPH). The magnitude of the transmantle pressure is small, on the order of a few Pascals, thereby hindering direct in vivo measurements. To complement previous computational efforts, we perform here, for the first time, in vitro experiments involving an MRI-informed experimental model of the cerebral aqueduct flow. Methods: Dimensional analysis is used in designing a scaled-up model of the aqueduct flow, with physical similarity maintained by adjusting the flow frequency and the properties of the working fluid. High-resolution MRI images are used to generate a 3D-printed anatomically correct aqueduct model. A programmable pump is used to generate a pulsatile flow rate signal measured from phase-contrast MRI. Extensive experiments are performed to investigate the relation between the cyclic fluctuations of the aqueduct flow rate and the transmantle pressure fluctuation over the range of flow conditions commonly encountered in healthy subjects. The time-dependent pressure measurements are validated through comparisons with predictions obtained with a previously derived computational model. Results: Parametric dependences of the pressure-fluctuation amplitude and its phase lag relative to the flow rate are delineated. The results indicate, for example, that the phase lag is nearly independent on the stroke volume. A simple expression relating the mean amplitude of the interventricular pressure difference (between third and fourth ventricle) with the stroke volume of the oscillatory flow is established. Conclusions: MRI-informed in-vitro experiments using an anatomically correct model of the cerebral aqueduct and a realistic flow rate have been used to characterize transmantle pressure. The quantitative results can be useful in enabling quick clinical assessments of transmantle pressure to be made from noninvasive phase contrast MRI measurements of aqueduct flow rates. The scaled-up experimental facility provides the ability to conduct future experiments specifically aimed at investigating altered CSF flow and associated transmantle pressure, as needed in connection with NPH studies.
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Live-cell microscopy imaging typically involves the use of high-quality glass-bottom chambers that allow cell culture, gaseous buffer exchange and optical properties suitable for microscopy applications. However, commercial sources of these chambers can add significant annual costs to cell biology laboratories. Consumer products in three-dimensional printing technology, for both Filament Deposition Modeling (FDM) and Masked Stereo Lithography (MSLA), have resulted in more biomedical research labs adopting the use of these devices for prototyping and manufacturing of lab plastic-based items, but rarely consumables. Here we describe a modular, live-cell chamber with multiple design options that can be mixed per experiment. Single reusable carriers and the use of biodegradable plastics, in a hybrid of FDM and MSLA manufacturing methods, reduce plastic waste. The system is easy to adapt to bespoke designs, with concept-to-prototype in a single day, offers significant cost savings to the users over commercial sources, and no loss in dimensional quality or reliability.
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Microscopía , Impresión Tridimensional , Plásticos , Impresión , Reproducibilidad de los ResultadosRESUMEN
The use of genome wide association studies (GWAS) in Huntington's disease (HD) research, driven by unbiased human data analysis, has transformed the focus of new targets that could affect age at onset. While there is a significant depth of information on DNA damage repair, with many drugs and drug targets, most of this development has taken place in the context of cancer therapy. DNA damage repair in neurons does not rely on DNA replication correction mechanisms. However, there is a strong connection between DNA repair and neuronal metabolism, mediated by nucleotide salvaging and the poly ADP-ribose (PAR) response, and this connection has been implicated in other age-onset neurodegenerative diseases. Validation of leads including the mismatch repair protein MSH3, and interstrand cross-link repair protein FAN1, suggest the mechanism is driven by somatic CAG instability, which is supported by the protective effect of CAA substitutions in the CAG tract. We currently do not understand: how somatic instability is triggered; the state of DNA damage within expanding alleles in the brain; whether this damage induces mismatch repair and interstrand cross-link pathways; whether instability mediates toxicity, and how this relates to human ageing. We discuss DNA damage pathways uncovered by HD GWAS, known roles of other polyglutamine disease proteins in DNA damage repair, and a panel of hypotheses for pathogenic mechanisms.
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Reparación del ADN/genética , Estudio de Asociación del Genoma Completo , Inestabilidad Genómica/genética , Enfermedad de Huntington/genética , Ataxias Espinocerebelosas/genética , HumanosRESUMEN
The interpretation and measurement of the architectural organization of mitochondria depend heavily upon the availability of good software tools for filtering, segmenting, extracting, measuring, and classifying the features of interest. Images of mitochondria contain many flow-like patterns and they are usually corrupted by large amounts of noise. Thus, it is necessary to enhance them by denoising and closing interrupted structures. We introduce a new approach based on anisotropic nonlinear diffusion and bilateral filtering for electron tomography of mitochondria. It allows noise removal and structure closure at certain scales, while preserving both the orientation and magnitude of discontinuities without the need for threshold switches. This technique facilitates image enhancement for subsequent segmentation, contour extraction, and improved visualization of the complex and intricate mitochondrial morphology. We perform the extraction of the structure-defining contours by employing a variational level set formulation. The propagating front for this approach is an approximate signed distance function which does not require expensive re-initialization. The behavior of the combined approach is tested for visualizing the structure of a HeLa cell mitochondrion and the results we obtain are very promising.
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Tomografía con Microscopio Electrónico/métodos , Procesamiento de Imagen Asistido por Computador/métodos , Mitocondrias/química , Difusión , Células HeLa , Humanos , Aumento de la Imagen/métodosRESUMEN
Fungal sinusitis was once considered a rare disorder but is now reported with increasing frequency throughout the world. The classification of fungal sinusitis has evolved in the past two decades, and this entity is now thought to comprise five subtypes. Acute invasive fungal sinusitis, chronic invasive fungal sinusitis, and chronic granulomatous invasive fungal sinusitis make up the invasive group, whereas noninvasive fungal sinusitis is composed of allergic fungal sinusitis and fungus ball (fungal mycetoma). These five subtypes are distinct entities with different clinical and radiologic features. The treatment strategies for the subtypes are also different, as are their prognoses. An understanding of the different types of fungal sinusitis and knowledge of their particular radiologic features allow the radiologist to play a crucial role in alerting the clinician to use appropriate diagnostic techniques for confirmation. Prompt diagnosis and initiation of appropriate therapy are essential to avoid a protracted or fatal outcome.
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Imagen por Resonancia Magnética/métodos , Micosis/diagnóstico , Micosis/microbiología , Sinusitis/diagnóstico , Sinusitis/microbiología , Tomografía Computarizada por Rayos X/métodos , Adulto , Femenino , Humanos , Aumento de la Imagen/métodos , Masculino , Persona de Mediana Edad , Micosis/clasificación , Guías de Práctica Clínica como Asunto , Pautas de la Práctica en Medicina , Sinusitis/clasificaciónRESUMEN
A persistent trigeminal artery (PTA) is the most common carotid-vertebrobasilar anastomosis. PTA variants terminating on cerebellar arteries instead of the basilar artery have been reported previously. We present the first case of a PTA communicating with a fetal posterior communicating artery identified on a magnetic resonance angiogram. An understanding of these anatomical variants is important to clarify pathological processes that can help guide neurosurgical and endovascular procedures.
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Arterias Cerebrales/diagnóstico por imagen , Círculo Arterial Cerebral/diagnóstico por imagen , Malformaciones Arteriovenosas Intracraneales/diagnóstico por imagen , Malformaciones Arteriovenosas Intracraneales/fisiopatología , Adolescente , Femenino , Humanos , Malformaciones Arteriovenosas Intracraneales/terapia , Angiografía por Resonancia MagnéticaRESUMEN
A 30-year-old male presented with left facial pain and numbness. Initial MRI demonstrated an enhancing mass involving the left trigeminal nerve. Follow-up imaging showed interval growth with erosion of the sphenoid body. Surgical resection was performed and immunohistochemistry staining was consistent with an atypical teratoid/rhabdoid tumor. Awareness of this entity and its imaging features such as diffusion restriction, intratumoral hemorrhage, and bony destruction, can help guide confirmatory diagnostic testing and appropriate therapy.
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Neoplasias de los Nervios Craneales/patología , Tumor Rabdoide/patología , Nervio Trigémino/patología , Adulto , Neoplasias de los Nervios Craneales/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética , Masculino , Tumor Rabdoide/diagnóstico por imagen , Nervio Trigémino/diagnóstico por imagenRESUMEN
Jacobsen syndrome is a rare disorder caused by partial deletions of the long arm of chromosome 11. The phenotype is variable with involvement of multiple organ systems, resulting in congenital heart defects, blood dyscrasias, and impaired growth. We describe a case of a 30-year-old man with multiple ophthalmic manifestations and brain magnetic resonance imaging (MRI) that was remarkable for multiple T2-hyperintense subcortical white matter lesions. It is important to be aware that patients with Jacobsen syndrome may have nonspecific white changes seen on MRI.
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Encefalopatías/complicaciones , Encefalopatías/patología , Síndrome de Deleción Distal 11q de Jacobsen/complicaciones , Imagen por Resonancia Magnética , Sustancia Blanca/patología , Adulto , Medios de Contraste , Gadolinio , Humanos , Aumento de la Imagen , MasculinoRESUMEN
BACKGROUND: Astroblastoma is a rare neuroepithelial tumor that often originates in the cerebral hemisphere of children and young adults. Diagnosis of this obscure neoplasm can be difficult because these tumors are so infrequently encountered and share common radiological and neuropathological features of other glial neoplasms. As such, it should be included in the differential diagnosis of astrocytoma and ependymoma if the clinical and radiographic features suggest it. Standardized treatment of astroblastomas remains under dispute because of the lack of knowledge regarding the tumor and a paucity of studies in the literature. CASE DESCRIPTION: We present a case of a low-grade astroblastoma diagnosed in a 30-year-old female with seizures, headache, and vision changes. She underwent gross total resection and, without evidence of high-grade features, adjuvant therapy was not planned postoperatively. Post-operative surveillance suggested early recurrence, warranting referral to radiation therapy. Patient ended up expiring despite adjuvant therapy secondary to extensive recurrence and tumor metastasis. CONCLUSIONS: Astroblastoma must be considered in the differential of supratentorial tumors in children and young adults. Treatment of such, as suggested by most recent literature, includes gross total resection and adjuvant radiotherapy for lesions exhibiting high-grade features.
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Brain MRI scans revealed various occipital horn variants in a pedigreed baboon colony consisting of Papio hamadryas anubis and its hybrids. We retrospectively characterized these variants and evaluated their relationships to epilepsy phenotypes and scalp EEG findings. MRI scans (3D, T1-weighted) from 208 baboons (female, 134 female; male, 74; age [mean ± 1 SD], 16 ± 5 y) were reviewed; 139 (67%) of these animals also underwent scalp EEG previously. Occipital horn variants included elongation (extension of the occipital ventricle behind the mediobasal origin of the calcarine fissure), which affected 23 baboons (11%; 7 bilateral, 9 left, 7 right), and elongation with enlargement (colpocephaly), which occurred in 30 baboons (14%; 7 bilateral, 11 left, 12 right). The incidence of the occipital horn variants did not differ according to age or prenatal or perinatal history. Colpocephaly was associated with craniofacial trauma but not with witnessed seizures. Abnormal scalp EEG findings, including interictal epileptic discharges, did not differ significantly among the occipital horn morphologies. This study is the first radiologic description of occipital horn variants, particularly colpocephaly, in baboons. Whereas colpocephaly is frequently associated with other radiologic and neurologic abnormalities in humans, it is mostly an isolated finding in baboons. Because craniofacial trauma can occur in the setting of seizure-related falls, its increased association with colpocephaly may reflect an increased risk of seizures or of traumatic brain injuries due to seizures. Colpocephaly in baboons needs to be characterized prospectively radiologically, neurologically, histopathologically, and genetically to better understand its etiology and clinical significance.
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Encefalopatías/veterinaria , Epilepsia/veterinaria , Ventrículos Laterales/anomalías , Imagen por Resonancia Magnética/veterinaria , Enfermedades de los Monos/diagnóstico por imagen , Animales , Encéfalo/diagnóstico por imagen , Encefalopatías/diagnóstico por imagen , Electroencefalografía/veterinaria , Epilepsia/diagnóstico por imagen , Femenino , Ventrículos Laterales/diagnóstico por imagen , Masculino , Papio , Fenotipo , Estudios RetrospectivosRESUMEN
BACKGROUND: Pontine infarcts are common and often attributed to small vessel disease ("small deep infarcts") or basilar branch atherosclerosis ("wedge shaped"). A well-described morphological differentiation using magnetic resonance images has not been reported. Furthermore, whether risk factors and outcomes differ by morphology, or whether infarct morphology should guide secondary prevention strategy, is not well characterized. METHODS: All participants in the Secondary Prevention of Small Subcortical Strokes Study with magnetic resonance imaging -proven pontine infarcts were included. Infarcts were classified as well-circumscribed small deep (small deep infarct, i.e. lacunar), paramedian, atypical paramedian, or other based on diffusion-weighted imaging, T2/fluid-attenuated inversion recovery, and T1-magnetic resonance images. Inter-rater reliability was high (90% agreement, Cohen's kappa = 0.84). Clinical and radiologic features independently associated with small deep infarct versus paramedian infarcts were identified (multivariable logistic regression). Differences in stroke risk and death were assessed using Cox proportional hazards. RESULTS: Of the 3020 patients enrolled, 644 had pontine infarcts; 619 images were available: 302(49%) small deep infarct, 245 (40%) paramedian wedge, 35 (6%) atypical paramedian, and 37 (6%) other. Among vascular risk factors, only smoking (OR 2.1, 95% CI 1.3-3.3) was independently associated with small deep infarct versus paramedian infarcts; on neuroimaging, old lacunes on T1/fluid-attenuated inversion recovery (OR 1.8, 1.3-2.6) and intracranial stenosis (any location) ≥50% (OR 0.62, 0.41-0.96). Small deep infarct versus paramedian was not predictive of either recurrent stroke or death, and there was no interaction with assigned treatment. CONCLUSIONS: Pontine infarcts can be reliably classified based on morphology using clinical magnetic resonance images. Few risk factors differed between small deep infarct and paramedian infarcts with no differences in recurrent stroke or mortality. There was no difference in response to different antiplatelet or blood pressure treatment strategies between these two groups. REGISTRATION: http://www.clinicaltrials.gov/NCT00059306.
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Infarto Cerebral/clasificación , Infarto Cerebral/diagnóstico por imagen , Imagen por Resonancia Magnética , Puente/irrigación sanguínea , Puente/diagnóstico por imagen , Antihipertensivos/uso terapéutico , Aspirina/uso terapéutico , Infarto Cerebral/tratamiento farmacológico , Clopidogrel , Constricción Patológica/diagnóstico por imagen , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Inhibidores de Agregación Plaquetaria/uso terapéutico , Pronóstico , Recurrencia , Reproducibilidad de los Resultados , Factores de Riesgo , Accidente Vascular Cerebral Lacunar/clasificación , Accidente Vascular Cerebral Lacunar/diagnóstico por imagen , Accidente Vascular Cerebral Lacunar/tratamiento farmacológico , Ticlopidina/análogos & derivados , Ticlopidina/uso terapéutico , Resultado del TratamientoRESUMEN
The facial nerve is affected by a wide variety of pathologies, including congenital, traumatic, inflammatory, and neoplastic conditions. Imaging plays a vital role in the diagnosis of these pathologies. The facial nerve has a complex anatomy and course. A strong grasp of normal facial nerve anatomy is essential for the radiologist to maintain a high level of diagnostic sensitivity. This article details the normal imaging anatomy of the facial nerve and the imaging features of common facial nerve pathologies.
Asunto(s)
Enfermedades del Nervio Facial/patología , Nervio Facial/patología , Parálisis Facial/patología , Imagen por Resonancia Magnética , Tomografía Computarizada por Rayos X , Diagnóstico Diferencial , Nervio Facial/anatomía & histología , Nervio Facial/diagnóstico por imagen , Enfermedades del Nervio Facial/diagnóstico por imagen , Parálisis Facial/diagnóstico por imagen , HumanosRESUMEN
OBJECTIVE: There is little information about vaccine schedule compliance in very-low-birth-weight infants in developing countries. The aim of the study was to describe the compliance with the vaccine schedule among this population in Lima, Peru. PATIENTS AND METHODS: We conducted a prospective cohort study in four hospitals in Lima in infants with a birth-weight of less than 1500 g, followed from birth up to 12 months of age every 2 weeks. The date and age at administration of each vaccine was recorded RESULTS: 222 infants were enrolled. The median birth-weight was 1250 g (range 550-1499 g) and the median gestational age was 30.0 weeks (range 23-37 weeks). The mean age for the first pentavalent (DPT, Hib, HepB) and oral polio vaccine administration was 4.3 ± 1.4 months in infants with a birth-weight of < 1000 g vs. 3.1 ± 1.0 in infants with a birth-weight 1000-1500 g (p < 0.001); 4.1 ± 0.9 vs. 3.3 ± 1.1 for rotavirus (p < 0.05); and 5.1 ± 2.1 vs. 4.3 ± 1.8 for the 7-valent pneumococcal conjugated vaccine. Only 35% had received the three doses of oral polio and pentavalent vaccine by seven months, although by nine months 81% had received these vaccines. CONCLUSIONS: Vaccination of very-low-birth-weight infants in Peru is significantly delayed, especially in infants with a birth-weight of < 1000 g and lower gestational age. Urgent educational interventions targeting physicians and nurses should be implemented in order to improve vaccination rates and timing in these high risk populations.