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[en] Dysembryoplastic neuroepithelial tumors (DNTs) are long-term epilepsy associated tumors subdivided into simple and complex variants. The purpose of this study was to relate different DNT components identified on magnetic resonance imaging (MRI) to histopathological features and to test the hypothesis that glial nodules as a histopathological feature of complex variants induce an occasional glioma misdiagnosis. Clinical, MRI, and histopathologic features of DNTs operated between 1988 and 2008 were reviewed. From a total of 61 DNTs, 48 simple and 13 complex variants were identified. Multiple or single pseudocysts in a cortical/subcortical location with small cysts sometimes separated from the tumor represented the glioneuronal element and were found in all DNTs. FLAIR hyperintense tissue was found between pseudocysts but - in neocortical DNTs - also circumscript in deeper tumor parts. Calcification and hemorrhages in this location occurred in four of 13 complex variants, and one of these patients was also the only one with tumor growth. Patients with complex variants had earlier seizure onset, and complex variants were more often located outside the temporal lobe. Although complex variants represented a higher diagnostic challenge, misdiagnoses also occurred in simple variants. One of five of DNTs showed contrast enhancement, which varied on follow-up studies with enhancing parts becoming nonenhancing and vice versa. The glioneuronal element is readily identifiable on MRI and should be considered to support the DNT diagnosis. Complex DNT variants have a different clinical profile and a more variable histopathological and MRI appearance; however, misdiagnoses occasionally also occur in simple variants. (orig.)
[en] The authors propose a diagnostic method for cranio-cervical radiology in which the central beams of the frontal, lateral and axial views of the skull represent the axes of a system of spherical co-ordinates. The origin of the system is the intersection point of three planes: a sagittal plane and an horizontal one which both contain Twining's line and a frontal plane which contains the basion. Thus that point which is called 'point zero' represents the orthogonal projection of the basion on Twining's line. The first radiograph must be a lateral view of the skull, carried out in a traditional way. It permits one to fix point zero by measuring its distance to visible apparent structures of the skull, such as the nasion or external auditory meatus. Then the other radiographs, i.e. the second lateral and the frontal view, can be performed with their central beam coinciding with the axes of the system of co-ordinates centred at point zero. The purpose of this work is to present the diagram which, by comparison with a lateral view of the skull, makes it possible both to locate point zero and Twining's line in the patient's head and to study the morphology of the skull and the upper cervical spine in a systematic way on the basis of neuroradiology. The diagram is described and the conditions for its practical use in daily diagnosis are outlined. A number of examples of use are illustrated in normal and pathological conditions. (Auth.)
[en] Neuroradiology in the USA was started by the neurosurgeons Harvey Cushing, who personally made the first X-rays used to treat a patient with a neurological disability, and Walter Dandy, who first performed air ventriculography, ventriculoscopy, air encephalography and air myelography. The father of neuroradiology in the USA was Merrill Sosman, Cushing's associate. Modern neuroradiology was introduced into the USA from Europe by Mannie Schechter who was one of the original team of three Chief Editors of Neuroradiology. (orig.)
[en] Background: Diffusion tensor imaging (DTI) is a form of functional magnetic resonance imaging (MRI) that allows examination of the microstructural integrity of white matter in the brain. Dementia is a neurodegenerative disease, and DTI can provide indirect insights of the microstructural characteristics of brains in individuals with different forms of dementia. Purpose: To evaluate the value of DTI in the diagnosis and differential diagnosis of patients with subcortical ischemic vascular dementia (SIVD) and Alzheimer's disease (AD). Material and Methods: The study included 40 patients (20 AD patients and 20 SIVD patients) and 20 normal controls (NC). After routine MRI and DTI, fractional anisotropy (FA) and apparent diffusion coefficient (ADC) values were measured and compared in regions of interest (ROI). Results: Compared to NC and AD patients, SIVD patients had lower FA values and higher ADC values in the inferior-fronto-occipital fascicles (IFOF), genu of the corpus callosum (GCC), splenium of the corpus callosum (SCC), and superior longitudinal fasciculus (SLF). Compared to controls and SIVD patients, AD patients had lower FA values in the anterior frontal lobe, temporal lobe, hippocampus, IFOF, GCC, and CF; and higher ADC values in the temporal lobe and hippocampus. Conclusion: DTI can be used to estimate the white matter impairment in dementia patients. There were significant regional reductions of FA values and heightened ADC values in multiple regions in SIVD patients compared to AD patients. When compared with conventional MRI, DTI may provide a more objective method for the differential diagnosis of SIVD and AD disease patients who have only mild white matter alterations on T2-weighted imaging
[en] Addiction coopts the brain's neuronal circuits necessary for insight, reward, motivation, and social behaviors. This functional overlap results in addicted individuals making poor choices despite awareness of the negative consequences; it explains why previously rewarding life situations and the threat of judicial punishment cannot stop drug taking and why a medical rather than a criminal approach is more effective in curtailing addiction.
[en] This book deals with understanding of amalgamation for future digital society, which describes outline of amalgamation, ubiquitous environment, cognitive science I such as psychology and neurology, cognitive science II like philosophy, linguistics and anthropology, an automatic machine, evolution theory and amalgamation, brain science and consciousness, mind and software and creativity and art. Each chapter has introduction, composition, related science, function and models.