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Sample records for atrofia cortical posterior

  1. Frontoparietal cortical atrophy with gliosis in the gray matter of cerebral cortex: case report Atrofia cortical frontoparietal com gliose na substância cinzenta do córtex cerebral: relato de caso

    Directory of Open Access Journals (Sweden)

    Paulo Roberto de Brito-Marques

    2002-06-01

    região periventricular, centro semi-oval bilateral, e alta hiperintensidade de sinal na região da cápsula interna esquerda, além de leve atrofia bilateral nos lobos frontoparietais. Tomografia cerebral por emissão de fóton único revelou hipoperfusão de intensidade moderada nos lobos frontais e severa nos parietais, especialmente à esquerda. Os achados de necrópsia evidenciaram atrofia cortical, sendo severa nos lobos frontais, moderada nos parietais e leve no terço posterior dos temporais. Havia também leve atrofia no neostriado. Do ponto de vista histopatológico, existia na camada cortical severa perda neuronal com intensa gliose gemioscítica e grau variável de status spongiosus. As colorações por hematoxilina-eosina e Bielschowsky não revelaram células baloniformes (células de Pick e corpúsculos argirofílicos (corpos de Pick, degeneração neurofibrilar ou placa senil. As reações imuno-histoquímicas foram negativas para anti-ubiquitina, anti-tau, anti-beta amilóide e proteína anti-prion.

  2. [Posterior cortical atrophy with progressive visual agnosia].

    Science.gov (United States)

    Zarranz, J J; Lasa, A; Fernández, M; Lezcano, E; Pérez Bas, M; Varona, L; Ruiz, J; Beristain, X

    1995-03-01

    Interest in progressive focal cerebral syndromes associated with classical degenerative diseases has increased in recent years. Descriptions of posterior cortical atrophy with progressive visual agnosia are relatively rare. We present 5 patients (2 women) ranging in age between 57 and 72 years old. In all cases symptoms began and progressed with no known etiology. All cases were sporadic. The main clinical signs are difficulty in recognizing objects, colors, persons or places; topographical disorientation and visual memory alterations; alexia, simultagnosia, loss of ocular fixing and optic ataxia. Some patients presented other disturbances of praxis or memory and 2 progressed to global dementia. Language function was preserved and behavioral disturbances did not develop. The amplitude of the P100 visual evoked potential was low but latency was normal in 4 patients and prolonged in 1. Brain images showed atrophy and hypoperfusion in the parieto-occipital area. The neuropathology status of these patients is unknown. PMID:7756009

  3. The neuropsychiatric profile of posterior cortical atrophy.

    Science.gov (United States)

    Isella, Valeria; Villa, Giulia; Mapelli, Cristina; Ferri, Francesca; Appollonio, Ildebrando Marco; Ferrarese, Carlo

    2015-06-01

    We analyzed scores obtained at the Neuropsychiatric Inventory (NPI) by 20 patients with posterior cortical atrophy (PCA) and contrasted it with 20 patients having Alzheimer disease (AD). Patients with hallucinations and delusions were not included due to the high probability of a diagnosis of Lewy body disease. Prevalence of behavioral and psychological symptoms (BPSD) was 95% in the PCA group, the most frequent being apathy and anxiety. Cluster analysis on NPI subscales highlighted a behavioral subsyndrome characterized by agitated temper and irritability. Depression, anxiety, and apathy did not cluster with any other BPSD nor with each other. The PCA group showed a significantly higher proportion of anxious patients and worse anxiety score than patients with AD. No correlation was found between NPI data and demographic, clinical, or neuropsychological features nor were there significant differences for the same variables between anxious and nonanxious cases with PCA. In agreement with anecdotal reports, anxiety seems particularly relevant in PCA. PMID:25330926

  4. Abnormalities of fixation, saccade and pursuit in posterior cortical atrophy.

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    Shakespeare, Timothy J; Kaski, Diego; Yong, Keir X X; Paterson, Ross W; Slattery, Catherine F; Ryan, Natalie S; Schott, Jonathan M; Crutch, Sebastian J

    2015-07-01

    The clinico-neuroradiological syndrome posterior cortical atrophy is the cardinal 'visual dementia' and most common atypical Alzheimer's disease phenotype, offering insights into mechanisms underlying clinical heterogeneity, pathological propagation and basic visual phenomena (e.g. visual crowding). Given the extensive attention paid to patients' (higher order) perceptual function, it is surprising that there have been no systematic analyses of basic oculomotor function in this population. Here 20 patients with posterior cortical atrophy, 17 patients with typical Alzheimer's disease and 22 healthy controls completed tests of fixation, saccade (including fixation/target gap and overlap conditions) and smooth pursuit eye movements using an infrared pupil-tracking system. Participants underwent detailed neuropsychological and neurological examinations, with a proportion also undertaking brain imaging and analysis of molecular pathology. In contrast to informal clinical evaluations of oculomotor dysfunction frequency (previous studies: 38%, current clinical examination: 33%), detailed eyetracking investigations revealed eye movement abnormalities in 80% of patients with posterior cortical atrophy (compared to 17% typical Alzheimer's disease, 5% controls). The greatest differences between posterior cortical atrophy and typical Alzheimer's disease were seen in saccadic performance. Patients with posterior cortical atrophy made significantly shorter saccades especially for distant targets. They also exhibited a significant exacerbation of the normal gap/overlap effect, consistent with 'sticky fixation'. Time to reach saccadic targets was significantly associated with parietal and occipital cortical thickness measures. On fixation stability tasks, patients with typical Alzheimer's disease showed more square wave jerks whose frequency was associated with lower cerebellar grey matter volume, while patients with posterior cortical atrophy showed large saccadic intrusions

  5. Posterior cortical atrophy: visuomotor deficits in reaching and grasping

    OpenAIRE

    Meek, Benjamin P.; Shelton, Paul; Marotta, Jonathan J.

    2013-01-01

    Posterior Cortical Atrophy (PCA) is a rare clinical syndrome characterized by the predominance of higher-order visual disturbances such as optic ataxia, a characteristic of Balint's syndrome. Deficits result from progressive neurodegeneration of occipito-temporal and occipito-parietal cortices. The current study sought to explore the visuomotor functioning of four individuals with PCA by testing their ability to reach out and grasp real objects under various viewing conditions. Experiment 1 h...

  6. Posterior Cortical Atrophy: Visuomotor Deficits in Reaching and Grasping

    OpenAIRE

    Paul A Shelton; Marotta, Jonathan J.

    2013-01-01

    Posterior Cortical Atrophy (PCA) is a rare clinical syndrome characterised by the predominance of higher-order visual disturbances such as optic ataxia, a characteristic of Balint’s syndrome. Deficits result from progressive neurodegeneration of occipito-temporal and occipito-parietal cortices. The current study sought to explore the visuomotor functioning of four individuals with PCA by testing their ability to reach out and grasp real objects under various viewing conditions. Experiment 1 ...

  7. Posterior Cortical Atrophy: Visuomotor Deficits in Reaching and Grasping

    Directory of Open Access Journals (Sweden)

    Paul A Shelton

    2013-06-01

    Full Text Available Posterior Cortical Atrophy (PCA is a rare clinical syndrome characterised by the predominance of higher-order visual disturbances such as optic ataxia, a characteristic of Balint’s syndrome. Deficits result from progressive neurodegeneration of occipito-temporal and occipito-parietal cortices. The current study sought to explore the visuomotor functioning of four individuals with PCA by testing their ability to reach out and grasp real objects under various viewing conditions. Experiment 1 had participants reach out and grasp simple, rectangular blocks under visually- and memory-guided conditions. Experiment 2 explored participants’ abilities to accurately reach for objects located in their visual periphery. This investigation revealed that PCA patients demonstrate many of the same deficits that have been previously reported in other individuals with optic ataxia, such as ‘magnetic misreaching’ – a pathological reaching bias towards the point of visual fixation when grasping peripheral targets. Unlike many other individuals with optic ataxia, however, the patients in the current study also show symptoms indicative of damage to the more perceptual stream of visual processing, including abolished grip scaling during memory-guided grasping and deficits in face and object identification. These investigations are the first to perform a quantitative analysis of the visuomotor deficits exhibited by patients with Posterior Cortical Atrophy. Critically, this study helps characterize common symptoms of PCA, a vital first step for generating effective diagnostic criteria and therapeutic strategies for this understudied neurodegenerative disorder.

  8. Functional neural substrates of posterior cortical atrophy patients.

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    Shames, H; Raz, N; Levin, Netta

    2015-07-01

    Posterior cortical atrophy (PCA) is a neurodegenerative syndrome in which the most pronounced pathologic involvement is in the occipito-parietal visual regions. Herein, we aimed to better define the cortical reflection of this unique syndrome using a thorough battery of behavioral and functional MRI (fMRI) tests. Eight PCA patients underwent extensive testing to map their visual deficits. Assessments included visual functions associated with lower and higher components of the cortical hierarchy, as well as dorsal- and ventral-related cortical functions. fMRI was performed on five patients to examine the neuronal substrate of their visual functions. The PCA patient cohort exhibited stereopsis, saccadic eye movements and higher dorsal stream-related functional impairments, including simultant perception, image orientation, figure-from-ground segregation, closure and spatial orientation. In accordance with the behavioral findings, fMRI revealed intact activation in the ventral visual regions of face and object perception while more dorsal aspects of perception, including motion and gestalt perception, revealed impaired patterns of activity. In most of the patients, there was a lack of activity in the word form area, which is known to be linked to reading disorders. Finally, there was evidence of reduced cortical representation of the peripheral visual field, corresponding to the behaviorally assessed peripheral visual deficit. The findings are discussed in the context of networks extending from parietal regions, which mediate navigationally related processing, visually guided actions, eye movement control and working memory, suggesting that damage to these networks might explain the wide range of deficits in PCA patients. PMID:25976028

  9. Evaluating pathogenic dementia variants in posterior cortical atrophy.

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    Carrasquillo, Minerva M; Barber, Imelda; Lincoln, Sarah J; Murray, Melissa E; Camsari, Gamze Balci; Khan, Qurat ul Ain; Nguyen, Thuy; Ma, Li; Bisceglio, Gina D; Crook, Julia E; Younkin, Steven G; Dickson, Dennis W; Boeve, Bradley F; Graff-Radford, Neill R; Morgan, Kevin; Ertekin-Taner, Nilüfer

    2016-01-01

    Posterior cortical atrophy (PCA) is an understudied visual impairment syndrome most often due to "posterior Alzheimer's disease (AD)" pathology. Case studies detected mutations in PSEN1, PSEN2, GRN, MAPT, and PRNP in subjects with clinical PCA. To detect the frequency and spectrum of mutations in known dementia genes in PCA, we screened 124 European-American subjects with clinical PCA (n = 67) or posterior AD neuropathology (n = 57) for variants in genes implicated in AD, frontotemporal dementia, and prion disease using NeuroX, a customized exome array. Frequencies in PCA of the variants annotated as pathogenic or potentially pathogenic were compared against ∼ 4300 European-American population controls from the NHLBI Exome Sequencing Project. We identified 2 rare variants not previously reported in PCA, TREM2 Arg47His, and PSEN2 Ser130Leu. No other pathogenic or potentially pathogenic variants were detected in the screened dementia genes. In this first systematic variant screen of a PCA cohort, we report 2 rare mutations in TREM2 and PSEN2, validate our previously reported APOE ε4 association, and demonstrate the utility of NeuroX. PMID:26507310

  10. Effect of age at onset on cortical thickness and cognition in posterior cortical atrophy.

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    Suárez-González, Aida; Lehmann, Manja; Shakespeare, Timothy J; Yong, Keir X X; Paterson, Ross W; Slattery, Catherine F; Foulkes, Alexander J M; Rabinovici, Gil D; Gil-Néciga, Eulogio; Roldán-Lora, Florinda; Schott, Jonathan M; Fox, Nick C; Crutch, Sebastian J

    2016-08-01

    Age at onset (AAO) has been shown to influence the phenotype of Alzheimer's disease (AD), but how it affects atypical presentations of AD remains unknown. Posterior cortical atrophy (PCA) is the most common form of atypical AD. In this study, we aimed to investigate the effect of AAO on cortical thickness and cognitive function in 98 PCA patients. We used Freesurfer (v5.3.0) to compare cortical thickness with AAO both as a continuous variable, and by dichotomizing the groups based on median age (58 years). In both the continuous and dichotomized analyses, we found a pattern suggestive of thinner cortex in precuneus and parietal areas in earlier-onset PCA, and lower cortical thickness in anterior cingulate and prefrontal cortex in later-onset PCA. These cortical thickness differences between PCA subgroups were consistent with earlier-onset PCA patients performing worse on cognitive tests involving parietal functions. Our results provide a suggestion that AAO may not only affect the clinico-anatomical characteristics in AD but may also affect atrophy patterns and cognition within atypical AD phenotypes. PMID:27318138

  11. Non-pharmacological intervention for posterior cortical atrophy.

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    Weill-Chounlamountry, Agnès; Alves, Jorge; Pradat-Diehl, Pascale

    2016-08-16

    Posterior cortical atrophy (PCA) is a rare neurodegenerative condition characterized by progressive visual-perceptual deficits. Although the neurocognitive profile of PCA is a growing and relatively well-established field, non-pharmacological care remains understudied and to be widely established in clinical practice. In the present work we review the available literature on non-pharmacological approaches for PCA, such as cognitive rehabilitation including individual cognitive exercises and compensatory techniques to improve autonomy in daily life, and psycho-education aiming to inform people with PCA about the nature of their visual deficits and limits of cognitive rehabilitation. The reviewed studies represented a total of 7 patients. There is a scarcity of the number of studies, and mostly consisting of case studies. Results suggest non-pharmacological intervention to be a potentially beneficial approach for the partial compensation of deficits, improvement of daily functionality and improvement of quality of life. Clinical implications and future directions are also highlighted for the advancement of the field, in order to clarify the possible role of non-pharmacological interventions, and its extent, in PCA. PMID:27574605

  12. Memory Impairment at Initial Clinical Presentation in Posterior Cortical Atrophy.

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    Ahmed, Samrah; Baker, Ian; Husain, Masud; Thompson, Sian; Kipps, Christopher; Hornberger, Michael; Hodges, John R; Butler, Christopher R

    2016-04-23

    Posterior cortical atrophy (PCA) is characterized by core visuospatial and visuoperceptual deficits, and predominant atrophy in the parieto-occipital cortex. The most common underlying pathology is Alzheimer's disease (AD). Existing diagnostic criteria suggest that episodic memory is relatively preserved. The aim of this study was to examine memory performance at initial clinical presentation in PCA, compared to early-onset AD patients (EOAD). 15 PCA patients and 32 EOAD patients, and 34 healthy controls were entered into the study. Patients were tested on the Addenbrooke's Cognitive Examination (ACE-R), consisting of subscales in memory and visuospatial skills. PCA and EOAD patients were significantly impaired compared to controls on the ACE total score (p skills (p skills compared to EOAD patients (p presentation. The findings suggest that memory impairment must be considered in assessment and management of PCA. Further study into memory in PCA is warranted, since the ACE-R is a brief screening tool and is likely to underestimate the presence of memory impairment. PMID:27128371

  13. Visuo-Spatial Imagery Impairment in Posterior Cortical Atrophy: A Cognitive and SPECT Study

    OpenAIRE

    Simona Gardini; Letizia Concari; Salvatrice Pagliara; Caterina Ghetti; Annalena Venneri; Paolo Caffarra

    2011-01-01

    This study investigated the cognitive profile and the cerebral perfusion pattern in a highly educated 70 year old gentleman with posterior cortical atrophy (PCA). Visuo-perceptual abilities, spatial memory, spatial representation and navigation, visuo-spatial mental imagery, semantic and episodic-autobiographical memory were assessed. Regional cerebral blood flow (rCBF) was imaged with SPECT. Cognitive testing showed visual-perceptual impairment, apperceptive visual and landmark agnosia, topo...

  14. Posterior cortical atrophy: An investigation of scan paths generated during Face Matching tasks.

    OpenAIRE

    Meek, Benjamin P.; Keri eLocheed; Lawrence-Dewar, Jane M.; Paul A Shelton; Jonathan J Marotta

    2013-01-01

    When viewing a face, healthy individuals focus more on the area containing the eyes and upper nose in order to retrieve important featural and configural information. In contrast, individuals with face blindness (prosopagnosia) tend to direct fixations towards individual facial features – particularly the mouth. Presented here is an examination of face perception deficits in individuals with Posterior Cortical Atrophy (PCA). PCA is a rare progressive neurodegenerative disorder that is charact...

  15. Posterior cortical atrophy: an investigation of scan paths generated during face matching tasks

    OpenAIRE

    Meek, Benjamin P.; Locheed, Keri; Lawrence-Dewar, Jane M.; Shelton, Paul; Jonathan J Marotta

    2013-01-01

    When viewing a face, healthy individuals focus more on the area containing the eyes and upper nose in order to retrieve important featural and configural information. In contrast, individuals with face blindness (prosopagnosia) tend to direct fixations toward individual facial features—particularly the mouth. Presented here is an examination of face perception deficits in individuals with Posterior Cortical Atrophy (PCA). PCA is a rare progressive neurodegenerative disorder that is characteri...

  16. Posterior Cingulate, Precuneal & Retrosplenial Cortices: Cytology & Components of the Neural Network Correlates of Consciousness*

    OpenAIRE

    Vogt, Brent A.; Laureys, Steven

    2005-01-01

    Neuronal aggregates involved in conscious awareness are not evenly distributed throughout the CNS but are comprised of key components referred to as the neural network correlates of consciousness (NNCC). A critical node in this network is the retrosplenial, posterior cingulate, and precuneal cortices (RSC/PCC/PrCC). The cytological and neurochemical composition of this region is reviewed in relation to the Brodmann map. This region has the highest level of brain glucose metabolism and cytochr...

  17. Quantitative regional validation of the visual rating scale for posterior cortical atrophy

    International Nuclear Information System (INIS)

    Validate the four-point visual rating scale for posterior cortical atrophy (PCA) on magnetic resonance images (MRI) through quantitative grey matter (GM) volumetry and voxel-based morphometry (VBM) to justify its use in clinical practice. Two hundred twenty-nine patients with probable Alzheimer's disease and 128 with subjective memory complaints underwent 3T MRI. PCA was rated according to the visual rating scale. GM volumes of six posterior structures and the total posterior region were extracted using IBASPM and compared among PCA groups. To determine which anatomical regions contributed most to the visual scores, we used binary logistic regression. VBM compared local GM density among groups. Patients were categorised according to their PCA scores: PCA-0 (n = 122), PCA-1 (n = 143), PCA-2 (n = 79), and PCA-3 (n = 13). All structures except the posterior cingulate differed significantly among groups. The inferior parietal gyrus volume discriminated the most between rating scale levels. VBM showed that PCA-1 had a lower GM volume than PCA-0 in the parietal region and other brain regions, whereas between PCA-1 and PCA-2/3 GM atrophy was mostly restricted to posterior regions. The visual PCA rating scale is quantitatively validated and reliably reflects GM atrophy in parietal regions, making it a valuable tool for the daily radiological assessment of dementia. (orig.)

  18. Quantitative regional validation of the visual rating scale for posterior cortical atrophy

    Energy Technology Data Exchange (ETDEWEB)

    Moeller, Christiane; Benedictus, Marije R.; Koedam, Esther L.G.M.; Scheltens, Philip [VU University Medical Center, Alzheimer Center and Department of Neurology, Neuroscience Campus Amsterdam, P.O. Box 7057, Amsterdam (Netherlands); Flier, Wiesje M. van der [VU University Medical Center, Alzheimer Center and Department of Neurology, Neuroscience Campus Amsterdam, P.O. Box 7057, Amsterdam (Netherlands); VU University Medical Center, Department of Epidemiology and Biostatistics, Neuroscience Campus Amsterdam, P.O. Box 7057, Amsterdam (Netherlands); Versteeg, Adriaan; Wattjes, Mike P.; Barkhof, Frederik [VU University Medical Center, Department of Radiology and Nuclear Medicine, Neuroscience Campus Amsterdam, P.O. Box 7057, Amsterdam (Netherlands); Vrenken, Hugo [VU University Medical Center, Department of Radiology and Nuclear Medicine, Neuroscience Campus Amsterdam, P.O. Box 7057, Amsterdam (Netherlands); VU University Medical Center, Department of Physics and Medical Technology, Neuroscience Campus Amsterdam, P.O. Box 7057, Amsterdam (Netherlands)

    2014-02-15

    Validate the four-point visual rating scale for posterior cortical atrophy (PCA) on magnetic resonance images (MRI) through quantitative grey matter (GM) volumetry and voxel-based morphometry (VBM) to justify its use in clinical practice. Two hundred twenty-nine patients with probable Alzheimer's disease and 128 with subjective memory complaints underwent 3T MRI. PCA was rated according to the visual rating scale. GM volumes of six posterior structures and the total posterior region were extracted using IBASPM and compared among PCA groups. To determine which anatomical regions contributed most to the visual scores, we used binary logistic regression. VBM compared local GM density among groups. Patients were categorised according to their PCA scores: PCA-0 (n = 122), PCA-1 (n = 143), PCA-2 (n = 79), and PCA-3 (n = 13). All structures except the posterior cingulate differed significantly among groups. The inferior parietal gyrus volume discriminated the most between rating scale levels. VBM showed that PCA-1 had a lower GM volume than PCA-0 in the parietal region and other brain regions, whereas between PCA-1 and PCA-2/3 GM atrophy was mostly restricted to posterior regions. The visual PCA rating scale is quantitatively validated and reliably reflects GM atrophy in parietal regions, making it a valuable tool for the daily radiological assessment of dementia. (orig.)

  19. Hiding in plain sight: a closer look at posterior cortical atrophy.

    Science.gov (United States)

    Beh, Shin C; Muthusamy, Brinda; Calabresi, Peter; Hart, John; Zee, David; Patel, Vivek; Frohman, Elliot

    2015-02-01

    Posterior cortical atrophy (PCA) is a neurodegenerative syndrome dominated by deterioration of higher visual function (particularly visuospatial and visuoperceptual abilities). It is most commonly due to Alzheimer's disease pathology, but may also be caused by dementia with Lewy bodies, corticobasal degeneration or Creutzfeldt-Jakob disease. Patients often present to optometrists, ophthalmologists and/or neurologists with non-specific visual complaints, and unless clinicians seek the specific symptoms and signs of PCA (beyond that of the 'standard' neurological examination), this infrequent disorder is easily missed, delaying its diagnosis and treatment. We review the clinical features of PCA, focusing on its visual manifestations, to help neurologists recognise this important syndrome. PMID:25216669

  20. Cortical Dependence of Whisker Responses in Posterior Medial Thalamus In Vivo.

    Science.gov (United States)

    Mease, Rebecca A; Sumser, Anton; Sakmann, Bert; Groh, Alexander

    2016-08-01

    Cortical layer 5B (L5B) thick-tufted pyramidal neurons have reliable responses to whisker stimulation in anesthetized rodents. These cells drive a corticothalamic pathway that evokes spikes in thalamic posterior medial nucleus (POm). While a subset of POm has been shown to integrate both cortical L5B and paralemniscal signals, the majority of POm neurons are suggested to receive driving input from L5B only. Here, we test this possibility by investigating the origin of whisker-evoked responses in POm and specifically the contribution of the L5B-POm pathway. We compare L5B spiking with POm spiking and subthreshold responses to whisker deflections in urethane anesthetized mice. We find that a subset of recorded POm neurons shows early (early large EPSPs. In these neurons, the early large EPSPs matched L5B input criteria, were blocked by cortical inhibition, and also interacted with spontaneous Up state coupled large EPSPs. This result supports the view of POm subdivisions, one of which receives whisker signals predominantly via L5B neurons. PMID:27230219

  1. Influence of COMT Genotype on Antero-posterior Cortical Functional Connectivity Underlying Interference Resolution.

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    Jaspar, Mathieu; Manard, Marine; Dideberg, Vinciane; Bours, Vincent; Maquet, Pierre; Collette, Fabienne

    2016-02-01

    Genetic variability related to the catechol-O-methyltransferase (COMT) gene (Val(158)Met) has received increasing attention as a possible modulator of executive functioning and its neural correlates. However, this attention has generally centered on the prefrontal cortices because of the well-known direct impact of COMT enzyme on these cerebral regions. In this study, we were interested in the modulating effect of COMT genotype on anterior and posterior brain areas underlying interference resolution during a Stroop task. More specifically, we were interested in the functional connectivity between the right inferior frontal operculum (IFop), an area frequently associated with inhibitory efficiency, and posterior brain regions involved in reading/naming processes (the 2 main non-executive determinants of the Stroop effect). The Stroop task was administered during functional magnetic resonance imaging scanning to 3 groups of 15 young adults divided according to their COMT Val(158)Met genotype [Val/Val (VV), Val/Met (VM), and Met/Met (MM)]. Results indicate greater activity in the right IFop and the left middle temporal gyrus in homozygous VV individuals than in Met allele carriers. In addition, the VV group exhibited stronger positive functional connectivity between these 2 brain regions and stronger negative connectivity between the right IFop and left lingual gyrus. These results confirm the impact of COMT genotype on frontal functions. They also strongly suggest that differences in frontal activity influence posterior brain regions related to a non-executive component of the task. Particularly, changes in functional connectivity between anterior and posterior brain areas might correspond to compensatory processes for performing the task efficiently when the available dopamine level is low. PMID:25205659

  2. Screw fixation to the posterior cortical shell does not influence peak torque and pullout in anterior cervical plating

    OpenAIRE

    Pitzen, T.; Barbier, D.; Tintinger, F.; Steudel, W; Strowitzki, M.

    2002-01-01

    There is no consensus over whether screw fixation for anterior cervical plating should include the posterior cortical shell of the vertebral bodies or not. Thus, the purpose of this study was to investigate the function of the posterior cortical shell with respect to maximal screw torque and pullout force. Twenty-four fresh frozen human cervical vertebrae coming from six spinal segments C4–C7 were used. They were scanned for bone mineral density (BMD) and then assigned to two groups with comp...

  3. Clear Zone Formation around Screws in the Early Postoperative Stages after Posterior Lumbar Fusion Using the Cortical Bone Trajectory Technique

    OpenAIRE

    Ninomiya, Koshi; Iwatsuki, Koichi; Ohnishi, Yu-ichiro; Ohkawa, Toshika; Yoshimine, Toshiki

    2015-01-01

    Study Design Retrospective study. Purpose To evaluate the initial fixation using the cortical bone trajectory (CBT) technique for posterior lumbar fusion through assessment of the clear zones around the screws and the risk factors involved. Overview of Literature Postoperative radiolucent zones (clear zones) are an indicator of poor conventional pedicle screw fixation. Methods Between January 2013 and April 2014, 19 patients (8 men and 11 women) underwent posterior lumbar interbody fusion or ...

  4. Temporary interference over the posterior parietal cortices disrupts thermoregulatory control in humans.

    Directory of Open Access Journals (Sweden)

    Alberto Gallace

    Full Text Available The suggestion has recently been made that certain higher-order cortical areas involved in supporting multisensory representations of the body, and of the space around it, might also play a role in controlling thermoregulatory functions. Here we demonstrate that temporary interference with the function of one of these areas, the posterior parietal cortex, by repetitive transcranial magnetic stimulation, results in a decrease in limb temperature. By contrast, interference with the activity of a sensory-specific area (the primary somatosensory cortex had no effect on temperature. The results of this experiment suggest that associative multisensory brain areas might exert a top-down modulation over basic physiological control. Such a function might be part of a larger neural circuit responsible for maintaining the integrity of the body at both a homeostatic and a psychological level.

  5. Temporary Interference over the Posterior Parietal Cortices Disrupts Thermoregulatory Control in Humans

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    Gallace, Alberto; Soravia, Giovanna; Cattaneo, Zaira; Moseley, G. Lorimer; Vallar, Giuseppe

    2014-01-01

    The suggestion has recently been made that certain higher-order cortical areas involved in supporting multisensory representations of the body, and of the space around it, might also play a role in controlling thermoregulatory functions. Here we demonstrate that temporary interference with the function of one of these areas, the posterior parietal cortex, by repetitive transcranial magnetic stimulation, results in a decrease in limb temperature. By contrast, interference with the activity of a sensory-specific area (the primary somatosensory cortex) had no effect on temperature. The results of this experiment suggest that associative multisensory brain areas might exert a top-down modulation over basic physiological control. Such a function might be part of a larger neural circuit responsible for maintaining the integrity of the body at both a homeostatic and a psychological level. PMID:24622382

  6. Distinct Roles of the Prefrontal and Posterior Parietal Cortices in Response Inhibition

    Directory of Open Access Journals (Sweden)

    Xin Zhou

    2016-03-01

    Full Text Available The dorsolateral prefrontal cortex and posterior parietal cortex have been implicated in the planning of movements and inhibition of inappropriate responses, though their precise roles in these functions are not known. To address this question, we trained monkeys to perform memory-guided saccade and anti-saccade tasks and compared neural responses in the same animals. A population of neurons with no motor responses was also activated by a stimulus appearing out of the receptive field and could therefore mediate vector inversion. These neurons were found almost exclusively in the prefrontal cortex. Prefrontal cortical activity better predicted the level of performance in the task. Representation of the saccade goal also peaked in the prefrontal cortex at a time that was predictive of reaction time. These results suggest that the prefrontal cortex is the primary site of vector inversion in the cerebral cortex and explain the importance of this area in response inhibition.

  7. Posterior Cingulate, Precuneal & Retrosplenial Cortices: Cytology & Components of the Neural Network Correlates of Consciousness*

    Science.gov (United States)

    Vogt, Brent A.; Laureys, Steven

    2008-01-01

    Neuronal aggregates involved in conscious awareness are not evenly distributed throughout the CNS but are comprised of key components referred to as the neural network correlates of consciousness (NNCC). A critical node in this network is the retrosplenial, posterior cingulate, and precuneal cortices (RSC/PCC/PrCC). The cytological and neurochemical composition of this region is reviewed in relation to the Brodmann map. This region has the highest level of brain glucose metabolism and cytochrome c oxidase activity. Monkey studies suggest that the anterior thalamic projection likely drives RSC and PCC metabolism and that the midbrain projection to the anteroventral thalamic nucleus is a key coupling site between the brainstem system for arousal and cortical systems for cognitive processing and awareness. The pivotal role of RSC/PCC/PrCC in consciousness is demonstrated with posterior cingulate epilepsy cases, midcingulate lesions that de-afferent this region and are associated with unilateral sensory neglect, observations from stroke and vegetative state patients, alterations in blood flow during sleep, and the actions of anesthetics. Since this region is critically involved in self reflection, it is not surprising that it is similarly a site for the NNCC. Interestingly, information processing during complex cognitive tasks and during aversive sensations such as pain induces efforts to terminate self reflection and result in decreased processing in PCC/PrCC. Finally, anatomical relations between the neural correlates of mind and NNCC in the cingulate gyrus do not appear to overlap and suggests that mental function and conscious awareness may be mediated by two neural networks. PMID:16186025

  8. [Posterior cortical atrophy. Pathology, diagnosis and treatment of a rare form of dementia].

    Science.gov (United States)

    Ortner, M; Kurz, A

    2015-07-01

    The syndrome of posterior cortical atrophy (PCA) is a rare clinical manifestation of several neurodegenerative diseases which affect the parieto-occipital cortex. The most frequent underlying pathology is Alzheimer's disease but some cases are caused by Lewy body disease, progressive subcortical gliosis, corticobasal degeneration or prion diseases. The most prominent clinical feature of PCA is complex visual disturbances including object agnosia, simultanagnosia, optical ataxia and oculomotor apraxia while basic visual functions remain intact. These deficits lead to multiple impairments in activities of daily living that require visual control. On progression of the disease amnestic, apraxic and dysexecutive symptoms occur so that a global dementia gradually emerges. At the core of the diagnostic work-up are a detailed patient history, accurate analysis of behavior and neuropsychological testing. Structural and functional brain imaging are suitable to demonstrate the localization of the disease process. Measurement of cerebrospinal fluid proteins (e.g. beta amyloid, tau, phospho-tau and 14-3-3) serves to confirm or exclude Alzheimer's disease or prion diseases. The mainstay of treatment are non-pharmacological interventions to support activities of daily living and personal independence. These treatments include cognitive training and compensatory strategies which can be prescribed as neuropsychological treatment or occupational therapy. If Alzheimer's disease or Lewy body disease is the likely cause, a treatment with cholinesterase inhibitor may be tried. Caregiver education and support are another essential part of the treatment regimen as with all forms of dementia. PMID:25791802

  9. Cortical Connections of the Caudal Portion of Posterior Parietal Cortex in Prosimian Galagos.

    Science.gov (United States)

    Stepniewska, Iwona; Cerkevich, Christina M; Kaas, Jon H

    2016-06-01

    Posterior parietal cortex (PPC) of prosimian galagos includes a rostral portion (PPCr) where electrical stimulation evokes different classes of complex movements from different subregions, and a caudal portion (PPCc) where such stimulation fails to evoke movements in anesthetized preparations ( Stepniewska, Fang et al. 2009). We placed tracer injections into PPCc to reveal patterns of its cortical connections. There were widespread connections within PPCc as well as connections with PPCr and extrastriate visual areas, including V2 and V3. Weaker connections were with dorsal premotor cortex, and the frontal eye field. The connections of different parts of PPCc with visual areas were roughly retinotopic such that injections to dorsal PPCc labeled more neurons in the dorsal portions of visual areas, representing lower visual quadrant, and injections to ventral PPCc labeled more neurons in ventral portions of these visual areas, representing the upper visual quadrant. We conclude that much of the PPCc contains a crude representation of the contralateral visual hemifield, with inputs largely, but not exclusively, from higher-order visual areas that are considered part of the dorsal visuomotor processing stream. As in galagos, the caudal half of PPC was likely visual in early primates, with the rostral PPC half mediating sensorimotor functions. PMID:26088972

  10. Counting or chunking? Mathematical and heuristic abilities in patients with corticobasal syndrome and posterior cortical atrophy.

    Science.gov (United States)

    Spotorno, Nicola; McMillan, Corey T; Powers, John P; Clark, Robin; Grossman, Murray

    2014-09-30

    A growing amount of empirical data is showing that the ability to manipulate quantities in a precise and efficient fashion is rooted in cognitive mechanisms devoted to specific aspects of numbers processing. The analog number system (ANS) has a reasonable representation of quantities up to about 4, and represents larger quantities on the basis of a numerical ratio between quantities. In order to represent the precise cardinality of a number, the ANS may be supported by external algorithms such as language, leading to a "precise number system". In the setting of limited language, other number-related systems can appear. For example the parallel individuation system (PIS) supports a "chunking mechanism" that clusters units of larger numerosities into smaller subsets. In the present study we investigated number processing in non-aphasic patients with corticobasal syndrome (CBS) and posterior cortical atrophy (PCA), two neurodegenerative conditions that are associated with progressive parietal atrophy. The present study investigated these number systems in CBS and PCA by assessing the property of the ANS associated with smaller and larger numerosities, and the chunking property of the PIS. The results revealed that CBS/PCA patients are impaired in simple calculations (e.g., addition and subtraction) and that their performance strongly correlates with the size of the numbers involved in these calculations, revealing a clear magnitude effect. This magnitude effect was correlated with gray matter atrophy in parietal regions. Moreover, a numeral-dots transcoding task showed that CBS/PCA patients were able to take advantage of clustering in the spatial distribution of the dots of the array. The relative advantage associated with chunking compared to a random spatial distribution correlated with both parietal and prefrontal regions. These results shed light on the properties of systems for representing number knowledge in non-aphasic patients with CBS and PCA. PMID:25278132

  11. Quantifying and comparing the pattern of thalamic and cortical projections to the posterior auditory field in hearing and deaf cats.

    Science.gov (United States)

    Butler, Blake E; Chabot, Nicole; Lomber, Stephen G

    2016-10-15

    Following sensory loss, compensatory crossmodal reorganization occurs such that the remaining modalities are functionally enhanced. For example, behavioral evidence suggests that peripheral visual localization is better in deaf than in normal hearing animals, and that this enhancement is mediated by recruitment of the posterior auditory field (PAF), an area that is typically involved in localization of sounds in normal hearing animals. To characterize the anatomical changes that underlie this phenomenon, we identified the thalamic and cortical projections to the PAF in hearing cats and those with early- and late-onset deafness. The retrograde tracer biotinylated dextran amine was deposited in the PAF unilaterally, to label cortical and thalamic afferents. Following early deafness, there was a significant decrease in callosal projections from the contralateral PAF. Late-deaf animals showed small-scale changes in projections from one visual cortical area, the posterior ectosylvian field (EPp), and the multisensory zone (MZ). With the exception of these minor differences, connectivity to the PAF was largely similar between groups, with the principle projections arising from the primary auditory cortex (A1) and the ventral division of the medial geniculate body (MGBv). This absence of large-scale connectional change suggests that the functional reorganization that follows sensory loss results from changes in synaptic strength and/or unmasking of subthreshold intermodal connections. J. Comp. Neurol. 524:3042-3063, 2016. © 2016 Wiley Periodicals, Inc. PMID:27019080

  12. Elizabeth Warrington Prize Lecture. Seeing why they cannot see: understanding the syndrome and causes of posterior cortical atrophy.

    Science.gov (United States)

    Crutch, Sebastian J

    2014-09-01

    Posterior cortical atrophy (PCA) is a syndrome defined by focal neurodegeneration of the parietal, occipital, and occipito-temporal cortices and associated with progressive dysfunction of visual processing, praxis, numeracy and reading. The condition is most commonly caused by (and viewed as an atypical presentation of) Alzheimer's disease, although can also be caused by other degenerative diseases. The current paper examines the relationship of PCA to other degenerative syndromes, and considers what comparisons of these syndromes and disease phenotypes can tell us about underlying disease mechanisms. The focus then turns to neuropsychological investigations of the cognitive basis of symptoms which, although unusual in the broader context of a dementia clinic, are particularly characteristic of the PCA syndrome, before exploring implications for clinical management and patient and carer support. PMID:23458247

  13. Estudio sobre la evolución de la atrofia retiniana en pacientes con coriorretinopatía serosa central tratados con terapia fotodinámica

    OpenAIRE

    Sierra Rodríguez, María Ángeles

    2015-01-01

    Estudio sobre la evolución de la atrofia retiniana en pacientes con coriorretinopatía serosa central tratados con terapia fotodinámica. Quermos demostrar la correlación entre la atrofia retiniana posterior al tratamiento de la coriorretinopatía serosa central (CSC) con terapia fotodinámica (TFD) con verteporfina y los distintos factores asociados: edad del paciente, tiempo transcurrido desde el diagnóstico, dosis de verteporfina empleada, número de sesiones necesarias para la completa reab...

  14. Atypical form of Alzheimer's disease with prominent posterior cortical atrophy: a review of lesion distribution and circuit disconnection in cortical visual pathways

    Science.gov (United States)

    Hof, P. R.; Vogt, B. A.; Bouras, C.; Morrison, J. H.; Bloom, F. E. (Principal Investigator)

    1997-01-01

    In recent years, the existence of visual variants of Alzheimer's disease characterized by atypical clinical presentation at onset has been increasingly recognized. In many of these cases post-mortem neuropathological assessment revealed that correlations could be established between clinical symptoms and the distribution of neurodegenerative lesions. We have analyzed a series of Alzheimer's disease patients presenting with prominent visual symptomatology as a cardinal sign of the disease. In these cases, a shift in the distribution of pathological lesions was observed such that the primary visual areas and certain visual association areas within the occipito-parieto-temporal junction and posterior cingulate cortex had very high densities of lesions, whereas the prefrontal cortex had fewer lesions than usually observed in Alzheimer's disease. Previous quantitative analyses have demonstrated that in Alzheimer's disease, primary sensory and motor cortical areas are less damaged than the multimodal association areas of the frontal and temporal lobes, as indicated by the laminar and regional distribution patterns of neurofibrillary tangles and senile plaques. The distribution of pathological lesions in the cerebral cortex of Alzheimer's disease cases with visual symptomatology revealed that specific visual association pathways were disrupted, whereas these particular connections are likely to be affected to a less severe degree in the more common form of Alzheimer's disease. These data suggest that in some cases with visual variants of Alzheimer's disease, the neurological symptomatology may be related to the loss of certain components of the cortical visual pathways, as reflected by the particular distribution of the neuropathological markers of the disease.

  15. Diagnostic value of 18F-FDG PET and 11C-PIB PET on early stage posterior cortical atrophy

    Directory of Open Access Journals (Sweden)

    Shuai LIU

    2015-08-01

    Full Text Available Background  Posterior cortical atrophy (PCA is a kind of progressive neurodegenerative disease with cortical visual impairment as the first symptom. Because of rare clinical incidence, early onset age, special clinical symptoms and unobvious MRI abnormality, the definitive diagnosis of PCA is difficult. This study used 18F-fluoro-2-deoxy-D-glucose (18F-FDG PET and 11C-Pittsburgh compound B (11C-PIB PET for PCA patients with unobvious MRI abnormality, so as to discuss the value of PET in the early diagnosis of PCA.  Methods  Five patients diagnosed as PCA in our hospital between April 2012 and March 2015 were enrolled in this study. Cognitive function was measured by Mini-Mental State Examination (MMSE, Montreal Cognitive Assessment (MoCA, Activities of Daily Living (ADL and Clock Drawing Test (CDT. Brain MRI, 18F-FDG PET and 11C-PIB PET were performed to analyze glucose metabolism and perfusion of posterior cortex.  Results Neuropsychological tests revealed that the ability of writing, calculating, visuospatial and executive function of all these patients were impaired. Color vision tests showed abnormal results. MRI showed that the posterior atrophy (PA scores were 0-2 (average 1 on the left side and 0-1 (average 0.80 on the right side. The medial temporal atrophy (MTA scores were 1-3 (average 1.80 on the left side and 1-4 (average 2 on the right side. The ventricular enlargement (VE scores were 1-2 (average 1.80 on the left side and 1-2 (average 1.60 on the right side. 18F-FDG PET showed glucose metabolism decreased obviously on bilateral temporo-parieto-occipital cortex, precuneus and cingulate gyrus, and slightly on frontal lobes and subcortical structure. 11C-PIB PET showed radioactive 11C-PIB deposition on bilateral frontal, temporal, parietal and occipital cortex, and the outline of cerebellar cortex was clear.  Conclusions  For PCA patients whose parietal and occipital cortical atrophy is not obvious on MRI, 18F-FDG PET

  16. Posterior cortical atrophy - a prototypical case of dementia beginning with visual symptoms: case report

    OpenAIRE

    2013-01-01

    Dementia presenting with prominent higher order visual symptoms may be observed in a range of neurodegenerative conditions and is often challenging to diagnose. We describe a case of progressive dementia presenting with prominent visual cortical symptoms. A 55-year-old, right-handed, woman with early onset of visual impairment not associated with anterior visual pathology, presenting with dyslexia, visual agnosia, Balint's syndrome, and spatial disorientation. Ophthalmologists should consider...

  17. Modulation of cortical vestibular processing by somatosensory inputs in the posterior insula

    OpenAIRE

    Hashimoto, Teruo; Taoka, Miki; Obayashi, Shigeru; Hara, Yukihiro; Tanaka, Michio; Iriki, Atsushi

    2013-01-01

    Primary objective To study the mechanism of somatosensory-vestibular interactions, this study examined the effects of somatosensory inputs on body sway induced by galvanic vestibular stimulation (GVS) in healthy participants and persons with brain injury in the posterior insula, a region constituting a part of the parietoinsular vestibular cortex. Research design This study adopted an experimental, controlled, repeated measures design. Methods and procedures Participants were 11 healthy indiv...

  18. An Anterior-to-Posterior Shift in Midline Cortical Activity in Schizophrenia During Self-Reflection

    OpenAIRE

    Holt, Daphne J.; Cassidy, Brittany S.; Andrews-Hanna, Jessica R.; Lee, Su Mei; Coombs, Garth; Goff, Donald C.; Gabrieli, John D.; Moran, Joseph M.

    2010-01-01

    Background Deficits in social cognition, including impairments in self-awareness, contribute to the overall functional disability associated with schizophrenia. Studies in healthy subjects have shown that social cognitive functions, including self-reflection, rely on the medial prefrontal cortex (mPFC) and posterior cingulate gyrus, and these regions exhibit highly correlated activity during “resting” states. In this study, we tested the hypothesis that patients with schizophrenia show dys...

  19. Posterior cortical atrophy - a prototypical case of dementia beginning with visual symptoms: case report

    Directory of Open Access Journals (Sweden)

    Leonardo Ferreira Caixeta

    2013-10-01

    Full Text Available Dementia presenting with prominent higher order visual symptoms may be observed in a range of neurodegenerative conditions and is often challenging to diagnose. We describe a case of progressive dementia presenting with prominent visual cortical symptoms. A 55-year-old, right-handed, woman with early onset of visual impairment not associated with anterior visual pathology, presenting with dyslexia, visual agnosia, Balint's syndrome, and spatial disorientation. Ophthalmologists should consider this condition especially in presenile patients with slowly progressive higher-order visual symptoms. Although described in association with different conditions, it may also occur in Alzheimer disease.

  20. Behavioral consequences of selective damage to frontal pole and posterior cingulate cortices.

    Science.gov (United States)

    Mansouri, Farshad A; Buckley, Mark J; Mahboubi, Majid; Tanaka, Keiji

    2015-07-21

    Frontal pole cortex (FPC) and posterior cingulate cortex (PCC) have close neuroanatomical connections, and imaging studies have shown coactivation or codeactivation of these brain regions during performance of certain tasks. However, they are among the least well-understood regions of the primate brain. One reason for this is that the consequences of selective bilateral lesions to either structure have not previously been studied in any primate species. We studied the effects of circumscribed bilateral lesions to FPC or PCC on monkeys' ability to perform an analog of Wisconsin Card Sorting Test (WCST) and related tasks. In contrast to lesions in other prefrontal regions, neither posttraining FPC nor PCC lesions impaired animals' abilities to follow the rule switches that frequently occurred within the WCST task. However, FPC lesions were not without effect, because they augmented the ability of animals to adjust cognitive control after experiencing high levels of conflict (whereas PCC lesions did not have any effect). In addition, FPC-lesioned monkeys were more successful than controls or PCC-lesioned animals at remembering the relevant rule across experimentally imposed distractions involving either an intervening secondary task or a surprising delivery of free reward. Although prefrontal cortex posterior to FPC is specialized for mediating efficient goal-directed behavior to maximally exploit reward opportunities from ongoing tasks, our data led us to suggest that FPC is, instead, specialized for disengaging executive control from the current task and redistributing it to novel sources of reward to explore new opportunities/goals. PMID:26150522

  1. Efeitos da injeção subtenoniana posterior de corticóide em pacientes com uveíte

    OpenAIRE

    Finamor Luciana Peixoto; Dimantas Maria Angélica P.; Campos Vânia Ewert de; Prata Jr. João Antônio; Muccioli Cristina

    2003-01-01

    OBJETIVO: Determinar os efeitos da injeção subtenoniana posterior de corticóide (ISPC) sobre a pressão intra-ocular (Po) e acuidade visual em uma série de pacientes com uveíte. MÉTODOS: Estudo prospectivo de 18 pacientes que foram submetidos à injeção subtenoniana posterior de acetato de triancinolona (Kenalog® 40 mg - 9 pacientes, 14 injeções) ou acetato de metilprednisolona (Depomedrol® 40mg - 9 pacientes, 15 injeções) para tratamento de inflamação intra-ocular crônica e/ou edema macular ci...

  2. Resúmenes de los trabajos sobre la atrofia espinocerebelosa

    Directory of Open Access Journals (Sweden)

    Congreso Nacional de Neurolog'ia

    2010-03-01

    Full Text Available Cuba presenta la mayor prevalencia mundial de Ataxia Espinocerebelosa Tipo 2, con más de 8000 individuos en riesgo de haber heredado la enfermedad, por lo cual el desarrollo de investigaciones y proyectos de investigación para investigar y seguir las intervenciones que se desarrollan en esta dirección, son de gran importancia y constituyen verdaderas gruías de trabajo no solo para Cuba sino también para otros países. En el salón de Atrofias Espino Cerebelosas se presentan un total de 11 investigaciones que tratan de una manera u otra este tema. Los resúmenes de las mismas se pueden encontrar en este apartado.

  3. Efeitos da injeção subtenoniana posterior de corticóide em pacientes com uveíte

    Directory of Open Access Journals (Sweden)

    Finamor Luciana Peixoto

    2003-01-01

    Full Text Available OBJETIVO: Determinar os efeitos da injeção subtenoniana posterior de corticóide (ISPC sobre a pressão intra-ocular (Po e acuidade visual em uma série de pacientes com uveíte. MÉTODOS: Estudo prospectivo de 18 pacientes que foram submetidos à injeção subtenoniana posterior de acetato de triancinolona (Kenalog® 40 mg - 9 pacientes, 14 injeções ou acetato de metilprednisolona (Depomedrol® 40mg - 9 pacientes, 15 injeções para tratamento de inflamação intra-ocular crônica e/ou edema macular cistóide. RESULTADOS: A acuidade visual final melhorou em 92% dos pacientes após a primeira injeção periocular de corticóide. Cinqüenta por cento melhoraram 1 linha e 42% melhoraram pelo menos 3 linhas, sendo que o tempo médio para a melhora foi de 3 semanas. Aumento da pressão intra-ocular ocorreu em 44 % dos pacientes (8 pacientes com média de 31 mmHg, variando de 21 a 38 mmHg. O aumento da pressão intra-ocular foi mais freqüente nos pacientes jovens e nos que receberam Kenalog®, com início, em média, após 2,5 semanas. CONCLUSÃO: Ainjeção subtenoniana de corticóide é uma forma de tratamento eficaz para a baixa acuidade visual secundária a alguns tipos de uveíte, como uveíte intermediária, doença de Behçet, síndrome de Vogt-Koyanagi-Harada, vasculite retiniana e artrite reumatóide. Porém, pode induzir aumento da pressão intra-ocular em alguns pacientes, especialmente em crianças e jovens.

  4. Atrofia girata de coróide e retina: relato de caso Girate atrophy of the retina and choroid: case report

    Directory of Open Access Journals (Sweden)

    Emerson Kenji Oyamaguchi

    2003-08-01

    Full Text Available OBJETIVO: Relatar um caso de atrofia girata de coróide e retina com confirmação por meio da bioquímica do plasma. MÉTODO: Aferiu-se a melhor acuidade visual corrigida de ambos olhos (AO em tabela de Snellen. Foram realizados biomicroscopia do segmento anterior, refração, mapeamento de retina, angiografia fluoresceínica, campo visual e dosagem da ornitina sérica (aminoacidograma. RESULTADOS: Paciente de 22 anos, sexo feminino, cor branca, apresentando alta miopia e acuidade visual (AV 20/100 em AO. À biomicroscopia do segmento anterior apresentava catarata subcapsular posterior em AO. À oftalmoscopia foram verificadas lesões atróficas da coróide e da retina bem delimitadas em meia periferia de AO. O aminoacidograma constatou elevação correspondente ao complexo da ornitina. CONCLUSÃO: Relata-se um caso típico de atrofia girata, distrofia retiniana rara associada a hiperornitinemia.PURPOSE: To report a case of gyrate atrophy confirmed by biochemical blood analysis. METHODS: Best corrected visual acuity was evaluated. Biomicroscopy of the anterior segment, indirect ophthalmoscopy, fluorescein angiography and computerized visual fields were performed. Color vision was assessed and plasma ornithine level was determined. RESULTS: 22-year-old white female with high myopia, visual acuity of 20/100 in both eyes. Biomicroscopy showed posterior subcapsular cataract in both eyes. Retinography showed well-delineated atrophic lesions of the choroid and retina in the mid-periphery and around the optic nerve in both eyes. Blood aminoacid determination showed high levels of ornithine. CONCLUSION: We describe here a typical case of girate atrophy of the retina and choroid, a rare disease associated with high levels of plasma ornithine.

  5. Análise da freqüência de trombofilia em pacientes com atrofia branca de Milian Frequency analysis of thrombophilia in patients with atrophie blanche

    OpenAIRE

    Aline Donati Jorge; Bruno de Carvalho Fantini; Evandro A. Rivitti; Benabou, Joseph E; Cidia Vasconcellos; Paulo Ricardo Criado

    2007-01-01

    FUNDAMENTOS - Atrofia branca de Milian ou vasculopatia livedóide é entidade clinicopatológica rara, cuja patogênese não é completamente compreendida. OBJETIVOS - Avaliar casos de atrofia branca de Milian para verificar a prevalência de diversas trombofilias. MATERIAL E MÉTODOS - Quatorze pacientes foram submetidos a exames laboratoriais incluindo pesquisa de fator V (Leiden), protrombina mutante, dosagem de antitrombina, proteína S e C, pesquisa de anticorpos anticardiolipina e anticoagulante...

  6. Cirugía preprotésica e implantológica en pacientes con atrofia maxilar severa

    OpenAIRE

    R. González García; Naval Gias, Luis; Mario F. Muñoz Guerra; Sastre Pérez, Jesús; F.J. Rodríguez Campo

    2005-01-01

    Objetivos. Valoración del éxito en la osteointegración de los implantes dentales en pacientes con atrofia maxilar severa sometidos a cirugía de elevación de seno maxilar y técnica por aposición mediante el uso de injertos de hueso autólogo. Diseño del estudio. Se realiza estudio descriptivo y analítico de 27 pacientes con atrofia maxilar severa y edentulismo parcial o total, durante 4 años de seguimiento. Todos los casos fueron tratados mediante cirugía con utilización de injertos óseos autól...

  7. RECONSTRUCCIÓN DEL MAXILAR SUPERIOR POSTERIOR ATRÓFICO CON CÉLULAS MADRE MESENQUIMALES

    OpenAIRE

    Martí Pagès, Carles

    2009-01-01

    Se realiza un estudio clínico en el lnstituto de Cirugía Maxilofacial e Implantologia tras pasar el comité ético del Centro Medica Teknon. Es un estudio randomizado, controlado utilizando un diseño tipo "split mouth" en el cual cada paciente sirve de propio control. SE realiza a 5 pacientes, con atrofia posterior del maxilar superior sin posibilidad de instalar implantes fueron tratados con reconstrucción mediante la técnica de elevación sinusal bilateral, rellenando un sena con Bio-as...

  8. Reversible posterior leukoencephalopathy syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Eun Ja; Yu, Won Jong; Ahn, Kook Jin; Jung, So Lyung; Lee, Yeon Soo; Kim, Ji Chang; Kang, Si Won [The Catholic Univ. of Korea, Taejon (Korea, Republic of); Song, Chang Joon [Chungnam National Univ. School of Medicine, Cheonju (Korea, Republic of); Song, Soon-Young; Koo, Ja Hong [Kwandong Univ. College of Medicine, Myungji Hospital, Seoul (Korea, Republic of); Kim, Man Deuk [College of Medicine Pochon CHA Univ., Seoul (Korea, Republic of)

    2001-10-01

    To review reversible posterior leukoencephalopathy syndrome. We reviewed 22 patients (M:F=3:19; age, 17-46 years) with the characteristic clinical and imaging features of reversible posterior leukoencephalopathy syndrome. All underwent brain MRI, and in three cases both CT and MRI were performed. In one, MRA was obtained, and in eleven, follow-up MR images were obtained. We evaluated the causes of this syndrome, its clinical manifestations, and MR findings including the locations of lesions, the presence or absence of contrast enhancement, and the changes seen at follow-up MRI. Of the 22 patients, 13 had eclampsia (six during pregnancy and seven during puerperium). Four were receiving immunosuppressive therapy (three, cyclosporine ; one, FK 506). Four suffered renal failure and one had complicated migraine. The clinical manifestations included headache (n=12), visual disturbance (n=13), seizure (n=15), focal neurologic sign (n=3), and altered mental status (n=2). Fifteen patients had hypertension and the others normotension. MRI revealed that lesions were bilateral (n=20) or unilateral (n=2). In all patients the lesion was found in the cortical and subcortical areas of the parieto-occipital lobes ; other locations were the basal ganglia (n=9), posterior temporal lobe (n=8), frontal lobe (n=5), cerebellum (n=5), pons (n=2), and thalamus (n=1). All lesions were of high signal intensity on T2-weighted images, and of iso to low intensity on T1-weighted images. One was combined with acute hematoma in the left basal ganglia. In eight of 11 patients who underwent postcontrast T1-weighted MRI, there was no definite enhancement ; in one, enhancement was mild, and in tow, patchy. CT studies showed low attenuation, and MRA revealed mild vasospasm. The symptoms of all patients improved. Follow-up MRI in nine of 11 patients depicted complete resolution of the lesions ; in two, small infarctions remained but the extent of the lesions had decreased. Reversible posterior

  9. Reversible posterior leukoencephalopathy syndrome

    International Nuclear Information System (INIS)

    To review reversible posterior leukoencephalopathy syndrome. We reviewed 22 patients (M:F=3:19; age, 17-46 years) with the characteristic clinical and imaging features of reversible posterior leukoencephalopathy syndrome. All underwent brain MRI, and in three cases both CT and MRI were performed. In one, MRA was obtained, and in eleven, follow-up MR images were obtained. We evaluated the causes of this syndrome, its clinical manifestations, and MR findings including the locations of lesions, the presence or absence of contrast enhancement, and the changes seen at follow-up MRI. Of the 22 patients, 13 had eclampsia (six during pregnancy and seven during puerperium). Four were receiving immunosuppressive therapy (three, cyclosporine ; one, FK 506). Four suffered renal failure and one had complicated migraine. The clinical manifestations included headache (n=12), visual disturbance (n=13), seizure (n=15), focal neurologic sign (n=3), and altered mental status (n=2). Fifteen patients had hypertension and the others normotension. MRI revealed that lesions were bilateral (n=20) or unilateral (n=2). In all patients the lesion was found in the cortical and subcortical areas of the parieto-occipital lobes ; other locations were the basal ganglia (n=9), posterior temporal lobe (n=8), frontal lobe (n=5), cerebellum (n=5), pons (n=2), and thalamus (n=1). All lesions were of high signal intensity on T2-weighted images, and of iso to low intensity on T1-weighted images. One was combined with acute hematoma in the left basal ganglia. In eight of 11 patients who underwent postcontrast T1-weighted MRI, there was no definite enhancement ; in one, enhancement was mild, and in tow, patchy. CT studies showed low attenuation, and MRA revealed mild vasospasm. The symptoms of all patients improved. Follow-up MRI in nine of 11 patients depicted complete resolution of the lesions ; in two, small infarctions remained but the extent of the lesions had decreased. Reversible posterior

  10. Uso de Polietigel® intra-orbitário em paciente com atrofia hemifacial progressiva: relato de caso

    OpenAIRE

    Sampaio Junior Amilton de Almeida; Kafuri Fabrício; Schellini Silvana Artioli; Rossa Romualdo

    2004-01-01

    O objetivo é relatar o caso de portadora de atrofia hemifacial progressiva, atendida na Faculdade de Medicina de Botucatu-UNESP: A paciente do sexo feminino, 43 anos, branca, queixava-se de "afundamento" progressivo do olho esquerdo e região orbitária há aproximadamente 10 anos, com dor na região periorbitária ipsilateral e diminuição da acuidade visual. O exame tomográfico confirmou a hipótese e o tratamento foi feito com injeção de Polietigel® na órbita, com bom resultado estético e melhora...

  11. Putative cortical dopamine levels affect cortical recruitment during planning ☆

    OpenAIRE

    Fallon, S.J.; Hampshire, A.; Williams-Gray, C.H.; Barker, R A; Owen, A. M.

    2013-01-01

    Planning, the decomposition of an ultimate goal into a number of sub-goals is critically dependent upon fronto-striatal dopamine (DA) levels. Here, we examined the extent to which the val158met polymorphism in the catechol O-methyltransferase (COMT) gene, which is thought to primarily alter cortical DA levels, affects performance and fronto-parietal activity during a planning task (Tower of London). COMT genotype was found to modulate activity in the left superior posterior parietal cortex (S...

  12. Cortical bone thickness in the buccal posterior region of the upper and lower jaw for orthodontic mini-implants%后牙区颊侧牙槽骨微植体支抗植入区域骨皮质厚度CBCT测量分析

    Institute of Scientific and Technical Information of China (English)

    王谋; 张定铭; 周建萍; 戴红卫

    2012-01-01

    Objective:To evaluate the thickness of buccal cortical bone at different height in posterior area of maxilla and mandible where mini-plants was inserted. Methods-.Thirty cone-beam CT(CBCT) images were selected from the Affilited Stomatology Hospital, Chongqing Medical University. Thickness of cortical bone between canine distal and second molar mesial at the height of 3,5, and 7 mm from the alveolar crest was determined. The data were analyzed statistically. Results-.The thickness of buccal cortical bone in the mandible posterior area was greater than that of maxilla(P<0.001). Between canine and first molar in maxilla the thickness was the minimum at the height of 5 mm from the alveolar crest.The thickness of cortical bone between first molar and second molar in maxilla and mandible became greater along with the distance increase from the alveolar crest. Conclusion:The thickness of buccal cortical bone changes along with the position changing sagittally and vertically, which should be considered in mini-plants implantation. Between canine and first molar in maxilla,a position as far from or close to the alveolar crest as possible is optimal,while in mandible and between first molar and second molar in maxilla,a position as far from the alveolar crest as possible is the best.%目的:通过对上下颌骨后牙区颊侧在不同高度下的骨皮质厚度进行测量和统计分析,为选择微植体支抗植入的最适位点提供理论依据,提高植入后的稳定性.方法:选择重庆医科大学附属口腔医院正畸科患者锥形束CT(Cone-beam CT,CBCT)影像资料30例,测量上下颌骨尖牙远中到第二磨牙间根间区距牙槽嵴顶3、5、7 mm位点处骨皮质厚度,并对测量数据进行统计分析.结果:下颌后牙区颊侧骨皮质厚度大于上颌(P<O.001),上颌在尖牙到第一磨牙间骨皮质厚度在距离牙槽嵴顶5mm处最小,下颌及上颌第一磨牙和第二磨牙间颊侧骨皮质随距牙槽嵴顶增大而增大.

  13. Relação dose-dependente do uso crônico de fenitoína e atrofia cerebelar em pacientes com epilepsia Dose-related cerebellar atrophy in patients with epilepsy using phenytoin

    Directory of Open Access Journals (Sweden)

    ANDRÉ DEL NEGRO

    2000-06-01

    Full Text Available O uso crônico da fenitoína ou intoxicação aguda por essa droga produzem lesão cerebelar permanente com atrofia do vermis e hemisférios cerebelares, que pode ser evidenciada através de exames de neuroimagem. O objetivo deste estudo foi avaliar a correlação entre a dosagem e o tempo de uso da fenitoína com a ocorrência de atrofia cerebelar. Foram realizados levantamento de prontuários para a obtenção de dados clínicos e análise de tomografias de crânio para avaliação de atrofia cerebelar. Dos 66 pacientes estudados, 18 apresentaram atrofia moderada a severa, 15 atrofia leve e 33 foram considerados normais. Os pacientes com atrofia cerebelar moderada a severa foram aqueles com maior exposição à fenitoína (uso prolongado e dose total, apresentando diferença estatisticamente significativa se comparados aos pacientes com atrofia leve ou sem atrofia (p=0.02. Além disso, no subgrupo de pacientes em uso de fenitoína, aqueles com atrofia moderada a severa possuíam níveis séricos de fenitoína significativamente mais elevados que os pacientes com atrofia leve ou sem atrofia (p=0.008. Não houve relação entre duração do tratamento e dose de outros anticonvulsivantes e presença e grau de atrofia cerebelar. Os pacientes mais velhos apresentaram maior grau de atrofia cerebelar, indicando que o fator idade ou tempo de epilepsia, ou ambos, pode ser importante na determinação de degeneração cerebelar. Concluímos que apesar da possibilidade de lesão cerebelar relacionada a crises epilépticas repetidas, a contribuição da fenitoína pode ser claramente estabelecida como um dos determinantes da atrofia cerebelar, sobretudo naqueles pacientes com altas doses por tempo prolongado e níveis séricos elevados.The chronic treatment with phenytoin or the acute intoxication by this drug may cause permanent cerebellar injury with atrophy of cerebellum vermis and hemispheres, which can be detected by neuroimaging studies. The aim of

  14. Escleritis posterior bilateral Bilateral posterior scleritis

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    A. Zurutuza

    2011-08-01

    Full Text Available La escleritis posterior es un proceso inflamatorio de la parte posterior de la esclera. Su prevalencia es muy baja y el diagnóstico puede resultar complicado por la ausencia de signos oculares externos. Es más frecuente en mujeres. Cuando aparece en pacientes jóvenes no suele tener otras patologías asociadas, pero en mayores de 55 años hasta un tercio de los casos tienen relación con alguna enfermedad sistémica, sobre todo la artritis reumatoide. El diagnóstico de esta patología puede requerir un abordaje multidisciplinar y la colaboración de oftalmólogos con neurólogos, internistas o reumatólogos. En este artículo se describe un caso de escleritis posterior bilateral idiopática.Posterior scleritis is an inflammatory process of the posterior part of the sclera. Its prevalence is very low and its diagnosis can be complicated due to the absence of external ocular signs. It is more frequent in women. In young patients it does not usually have other associated pathologies, but in those over 55 years nearly one-third of the cases have a relation with some systemic disease, above all rheumatoid arthritis. The diagnosis of this pathology can require a multidisciplinary approach and the collaboration of ophthalmologists with neurologists, internists or rheumatologists. This article describes a case of idiopathic bilateral posterior scleritis.

  15. Pertinencia del uso de implantes dentales cortos en pacientes con atrofia ósea severa: revisión de la literatura

    OpenAIRE

    R. Azañón Hernández; I. Martínez Lara; J. Ferrer Gallego; R. Marzo Alzota

    2013-01-01

    El propósito de este artículo es determinar la pertinencia del uso de implantes cortos, definiéndolos como "aquellos cuya longitud es ≤8 mm" a través de la bibliografía existente. Hemos centrado la búsqueda en la comparación del uso de implantes de esta longitud, frente a otros tratamientos alternativos (injertos óseos, elevación de seno, transposición del nervio dentario, etc.) en pacientes con atrofia maxilar severa. Se dan respuesta a las siguientes cuestiones: ¿El uso de implantes dentale...

  16. Atrofia muscular espinal. Contribuciones para el conocimiento, prevención y tratamiento de la enfermedad y para la organización de la familia

    OpenAIRE

    Tizzano, Eduardo F.

    2007-01-01

    Este resumen refiere el trabajo realizado durante casi dos décadas dedicadas a la atención, investigación y experiencia en la atrofia muscular espinal (AME), una enfermedad de las neuronas motoras de la médula espinal. Casi todo el mundo conoce la poliomielitis, producida por el ataque de un virus a las neuronas motoras de la médula espinal. Los avances científicos han erradicado prácticamente la poliomielitis en nuestros niños y hoy en día constituye una enfermedad del pasado gracias a la va...

  17. Atrofia de la grasa facial en los pacientes VIH+. Tratamiento mediante inyección de tejido adiposo autólogo.

    OpenAIRE

    Fontdevila Font, Joan

    2008-01-01

    [spa] La atrofia facial (AF) en pacientes infectados por el VIH es la manifestación más visible de la lipoatrofia (LA) asociada al trastorno de lipodistrofia (LD). Su prevalencia se ha estimado en un 50% de pacientes bajo tratamiento antirretroviral y la etiología es desconocida aunque el tratamiento antirretroviral de gran actividad parece jugar un papel relevante en su patogénesis. El cambio de la fisonomía facial inducido por la LA en los pacientes VIH+ los delata, sintiéndose estigmatizad...

  18. Interoceptive awareness changes the posterior insula functional connectivity profile.

    Science.gov (United States)

    Kuehn, Esther; Mueller, Karsten; Lohmann, Gabriele; Schuetz-Bosbach, Simone

    2016-04-01

    Interoceptive awareness describes the ability to consciously perceive inner bodily signals, such as one's own heartbeat. The right anterior insula is assumed to mediate this ability. The role of the posterior insula, particularly posterior-to-anterior insula signal flows is less clear in this respect. We scanned 27 healthy people with either high or low interoceptive awareness using 3T fMRI, while they either monitored their own heartbeats, or external tones, respectively. We used a combination of network centrality and bivariate connectivity analyses to characterize changes in cortical signal flows between the posterior insula and the anterior insula during interoceptive awareness or exteroceptive awareness, respectively. We show that heartbeat monitoring was accompanied by reduced network centrality of the right posterior insula, and decreased functional connectivity strengths between the right posterior insula and the right mid and anterior insula. In addition, decreased signal flows between the right posterior insula and the bilateral anterior cingulate cortices, and the bilateral orbitofrontal cortices were observed during interoceptive awareness. Functional connectivity changes were only shown by people with high interoceptive awareness, and occurred specifically within the low-frequency range (i.e., own heartbeat. PMID:25613901

  19. Posterior knee pain

    OpenAIRE

    English, S.; Perret, D.

    2010-01-01

    Posterior knee pain is a common patient complaint. There are broad differential diagnoses of posterior knee pain ranging from common causes such as injury to the musculotendinous structures to less common causes such as osteochondroma. A precise understanding of knee anatomy, the physical examination, and of the differential diagnosis is needed to accurately evaluate and treat posterior knee pain. This article provides a review of the anatomy and important aspects of the history and physical ...

  20. Posterior Reversible Encephalopathy Syndrome

    OpenAIRE

    J Gordon Millichap

    2013-01-01

    Investigators at Children's Hospital of Montefiore, Albert Einstein College of Medicine, NY, determined the incidence of posterior reversible encephalopathy syndrome (PRES) in a pediatric critical care unit.

  1. Microsurgical anatomy of the posterior circulation

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    Pai Balaji

    2007-01-01

    Full Text Available Context: The microsurgical anatomy of the posterior circulation is very complex and variable. Surgical approaches to this area are considered risky due to the presence of the various important blood vessels and neural structures. Aims: To document the microsurgical anatomy of the posterior circulation along with variations in the Indian population. Materials and Methods: The authors studied 25 cadaveric brain specimens. Microsurgical dissection was carried out from the vertebral arteries to the basilar artery and its branches, the basilar artery bifurcation, posterior cerebral artery and its various branches. Measurements of the outer diameters of the vertebral artery, basilar artery and posterior cerebral artery and their lengths were taken. Results: The mean diameter of the vertebral artery was 3.4 mm on the left and 2.9 mm on the right. The diameter of the basilar artery varied from 3-7 mm (mean of 4.3 mm. The length varied from 24-35 mm (mean of 24.9 mm. The basilar artery gave off paramedian and circumferential perforating arteries. The origin of the anterior inferior cerebellar artery (AICA varied from 0-21 mm (mean 10.0 mm from the vertebrobasilar junction. The diameter of the AICA varied from being hypoplastic i.e., < 0.5 mm to 2 mm (mean 1.0 mm. The superior cerebellar artery (SCA arises very close to the basilar bifurcation, in our series (1-3 mm from the basilar artery bifurcation. The diameter of the SCA varied from 0.5-2.5 mm on both sides. The posterior cerebral artery (PCA is divided into four segments. The PCA gave rise to perforators (thalamoperforators, thalamogeniculate arteries, circumflex arteries and peduncular arteries, medial posterior choroidal artery, lateral posterior choroidal artery and cortical branches. In 39 specimens the P1 segment was found to be larger than the posterior communicating artery, in six specimens it was found to be equal to the diameter of the posterior communicating artery and in five specimens it

  2. A and B mode ultrasonography in preoperative evaluation of lens and posterior segment of dogs eyes with cataract

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    Bianca C. Martins

    2010-02-01

    Full Text Available Ultrasonography of the lens and posterior segment is an indispensable step in the preoperative evaluation of dogs with cataracts, since ophthalmoscopy is not feasible when there is opacification of the lens. This study evaluated the echographic conditions of cataractous lens and fundus of the eye in dogs affected by cataracts. The study was conducted in 30 dogs (56 eyes, 10 males and 20 females, with different types of cataracts at different stages of development. Echography in A and B modes, simultaneously, was carried out for the examination of the lens and posterior segment. The examinations revealed anterior cortical, posterior cortical and nuclear cataract in 12 eyes (21.4%, anterior cortical, posterior cortical, nuclear and posterior capsular in 23 eyes (41%, anterior cortical, posterior cortical and posterior capsular cataract in one eye (1.7%, anterior cortical and nuclear cataract in one eye (1.7%, anterior cortical, nuclear and posterior capsular cataract in five eyes (8.9%, and anterior cortical cataract in seven eyes (12.5%. Abnormal ultrasonographic alterations were observed in the posterior segment in 26 eyes evaluated (46.4%. Vitreal degeneration was detected in 12 eyes (21.4%, images of vitreal exudate or hemorrhage in seven eyes (12.5%, persistence of hyaloid artery in four eyes (7.1% and lens subluxation in three eyes (5.3%. The results obtained reiterate the importance of ultrasonography in canine patients presented for cataract surgery given that alterations of the posterior segment are difficult to identify in a clinical examination when the lens is opacified.A ultrassonografia do segmento posterior do bulbo do olho é etapa indispensável na avaliação de cães com catarata que serão submetidos à facectomia, uma vez que a oftalmoscopia não é factível quando há opacificação da lente, notadamente nas cataratas maduras. Este estudo avaliou as condições ecográficas da lente cataratogênica e do fundo de olho de c

  3. Posterior cortical dementia with alexia: neurobehavioural, MRI, and PET findings.

    OpenAIRE

    Freedman, L; Selchen, D H; Black, S E; Kaplan, R; Garnett, E. S.; Nahmias, C

    1991-01-01

    A progressive disorder of relatively focal but asymmetric biposterior dysfunction is described in a 54 year old right handed male. Initial clinical features included letter-by-letter alexia, visual anomia, acalculia, mild agraphia, constructional apraxia, and visuospatial compromise. Serial testing demonstrated relentless deterioration with additional development of transcortical sensory aphasia, Gerstmann's tetrad, and severe visuoperceptual impairment. Amnesia was not an early clinical feat...

  4. Multisensory Perception of Action in Posterior Temporal and Parietal Cortices

    Science.gov (United States)

    James, Thomas W.; VanDerKlok, Ross M.; Stevenson, Ryan A.; James, Karin Harman

    2011-01-01

    Environmental events produce many sensory cues for identifying the action that evoked the event, the agent that performed the action, and the object targeted by the action. The cues for identifying environmental events are usually distributed across multiple sensory systems. Thus, to understand how environmental events are recognized requires an…

  5. Posterior cruciate Iigament instabilities

    OpenAIRE

    Asik, Mehmet; Akpinar, Sercan; Taser, Omer; Goksan, Alp

    2004-01-01

    Posterior cruciate Iigament (PCL) injuries represent 3% to 20% of all knee Iigamentous injuries, but the diagnosis often is missed at initial evaluation. Diagnostic ability is increased by knowledge of knee biomechanics and selective Iigament cutting studies. The examiner must differentiate the isolated PCL injury from combined Iigamentous injury to determine appropriate treatment. Isolated acute PCL tears with Iess than 1O mm of posterior Iaxity at 90 degrees of flexion should be treated wit...

  6. The tibialis posterior tendon

    OpenAIRE

    Lhoste-Trouilloud, A.

    2012-01-01

    The tibialis posterior tendon is the largest and anteriormost tendon in the medial ankle. It produces plantar flexion and supination of the ankle and stabilizes the plantar vault. Sonographic assessment of this tendon is done with high-frequency, linear-array transducers; an optimal examination requires transverse retromalleolar, longitudinal retromalleolar, and distal longitudinal scans, as well as dynamic studies. Disorders of the posterior tibial tendon include chronic tendinopathy with pr...

  7. Pertinencia del uso de implantes dentales cortos en pacientes con atrofia ósea severa: revisión de la literatura

    Directory of Open Access Journals (Sweden)

    R. Azañón Hernández

    2013-12-01

    Full Text Available El propósito de este artículo es determinar la pertinencia del uso de implantes cortos, definiéndolos como "aquellos cuya longitud es ≤8 mm" a través de la bibliografía existente. Hemos centrado la búsqueda en la comparación del uso de implantes de esta longitud, frente a otros tratamientos alternativos (injertos óseos, elevación de seno, transposición del nervio dentario, etc. en pacientes con atrofia maxilar severa. Se dan respuesta a las siguientes cuestiones: ¿El uso de implantes dentales cortos es un tratamiento de resultados previsibles? ¿Los porcentajes de éxito a medio y largo plazo son equiparables a los de implantes con una longitud media estándar? ¿Pueden sustituir en determinadas situaciones clínicas a técnicas quirúrgicas avanzadas (injertos óseos, elevación de seno, distalización del nervio dentario disminuyendo con ello la morbilidad, los tiempos en la rehabilitación y los costes para el paciente? ¿Se requiere de un protocolo clínico y prostético específico para garantizar el éxito en la rehabilitación? ¿En qué casos de atrofia maxilar se contraindica esta técnica a favor de otras como son los implantes cigomáticos o los injertos óseos? A través de una búsqueda cuasi-sistemática en metabuscadores, agencias de evidencias (revisiones sistemáticas y bases de datos bibliográficos, exponemos la evolución de la evidencia al respecto, los últimos datos publicados y las conclusiones obtenidas.

  8. Manejo de las atrofias del maxilar superior clase V de Cawood y Howell mediante la adopción de la cirugía piezoeléctrica The management of atrophies classified as V class according to Cawood & Howell by piezo-electric surgery

    Directory of Open Access Journals (Sweden)

    F. Carini

    2009-08-01

    Full Text Available Introducción: Los casos analizados presentaban atrofias severas (V clase según Cawood y Howell (1, que se caracterizan por presentar una densidad de la cresta transversal inferior a 4 mm y vertical inferior a 6 mm; ello hace pensar en la posibilidad de una rehabilitación implanto-soportada. Objetivo: Evaluación de la rehabilitación de pacientes afectados por severa atrofia del maxilar superior clase V según Cawood y Howell (1 rehabilitados con elevación del seno maxilar e injerto de hueso autólogo. Materiales y métodos: Estudio longitudinal a partir de una muestra de 32 pacientes, con atrofia maxilar severa y edentulismo parcial o total. En todos los pacientes se ha colocado un injerto con técnica de reconstrucción onlay mono o bicortical y se ha adoptado la cirugía piezoeléctrica para realizar el elevación del seno, el cual podía ser mono o bilateral, de hueso autólogo procedente de la cresta ilíaca anterior. Seguimiento realizado durante 2 años. Resultados: A los dos años del control final, el 94,05% de todos los implantes colocados tras la intervención de elevación se presentan osteointegrados y cargados protésicamente. La cresta ilíaca anterior resulta ser la zona idónea para la extracción medular, necesaria para la elevación del seno. Las posibilidades de supervivencia del implante son realmente elevadas si se espera el tiempo clínico necesario para la recuperación y la integración del injerto. El éxito de todas las intervenciones de elevación del seno maxilar se debe a la adopción de la cirugía piezoeléctrica, que permite efectuar la incisión de entrada y realizar el desprendimiento de los tejidos con un traumatismo mínimo para la membrana de Schneider. La integridad de la membrana y la utilización de bone-chips de origen autólogo no ha hecho necesario recurrir a la utilización de membranas reabsorbibles, simplificando así el procedimiento quirúrgico. La utilización de la cresta ilíaca anterior

  9. Syntelencephaly associated with connected transhemispheric cleft of focal cortical dysplasia.

    Science.gov (United States)

    Fujimoto, S; Togari, H; Banno, T; Wada, Y

    1999-05-01

    The authors report a female with syntelencephaly associated with a connected transhemispheric cleft of focal cortical dysplasia. Syntelencephaly is a rare anomaly characterized by fusion of the hemispheres in the posterior frontal and parietal regions and is considered a new variant of holoprosencephaly. Cranial magnetic resonance imaging of the patient revealed syntelencephaly associated with bilateral fused clefts of focal cortical dysplasia without the pial-ependymal seam, which was regarded as an incomplete type of schizencephaly. The underlying mechanism is discussed. PMID:10371387

  10. Tibialis Posterior Tendon Entrapment Within Posterior Malleolar Fracture Fragment.

    Science.gov (United States)

    Fantry, Amanda; Lareau, Craig; Vopat, Bryan; Blankenhorn, Brad

    2016-01-01

    Management of posterior malleolus fractures continues to be controversial, with respect to both need for fixation and fixation methods. Fixation methods include an open posterior approach to the ankle as well as percutaneous reduction and fixation with or without arthroscopy for visualization of the articular surface. Plain radiographs are unreliable in identifying fracture pattern and intraoperative reduction, making arthroscopy a valuable adjunct to posterior malleolus fracture management. In this article, we report a case of tibialis posterior tendon entrapment within a posterior malleolus fracture, as identified by arthroscopy and managed with open reduction. Tibialis posterior tendon entrapment within a posterior malleolus has not been previously reported. Ankle arthroscopy for posterior malleolus fractures provides an opportunity to identify soft-tissue or tendinous entrapment, articular surface reduction, and articular cartilage injuries unlikely to be identified with fluoroscopy alone and should be considered in reduction and fixation of posterior malleolus fractures. PMID:26991573

  11. Posterior parietal cortex dynamically ranks topographic signals via cholinergic influence

    Directory of Open Access Journals (Sweden)

    John Broussard

    2012-06-01

    Full Text Available The hypothesis to be discussed in this review is that posterior parietal cortex is directly involved in selecting relevant stimuli and filtering irrelevant distractors. The posterior parietal cortex receives input from several sensory modalities and integrates them in part to direct the allocation of resources to optimize gains. In conjunction with prefrontal cortex, nucleus accumbens, and basal forebrain cholinergic nuclei, it comprises a network mediating sustained attentional performance. Numerous anatomical, neurophysiological, and lesion studies have substantiated the notion that the basic functions of the posterior parietal cortex are conserved from rodents to humans. One such function is the detection and selection of relevant stimuli necessary for making optimal choices or responses. The issues to be addressed here are how behaviorally relevant targets recruit oscillatory potentials and spiking activity of posterior parietal neurons compared to similar yet irrelevant stimuli. Further, the influence of cortical cholinergic input to posterior parietal cortex in learning and decision-making is also discussed. I propose that these neurophysiological correlates of attention are transmitted to frontal cortical areas contributing to the top down selection of stimuli in a timely manner.

  12. Frontoparietal cortical atrophy with gliosis in the gray matter of cerebral cortex: case report Atrofia cortical frontoparietal com gliose na substância cinzenta do córtex cerebral: relato de caso

    OpenAIRE

    Paulo Roberto de Brito-Marques; Roberto Vieira de Mello; Luciano Montenegro

    2002-01-01

    The case of a patient who suffered from progressive amnesia, depressive humor, language and visuospatial disturbances, and hallucination episodies with interference at the daily living activities is reported. She had moderate neuropsichological diffuse deficits at the first examination, especially at the executive and visuo-constructive functions. Her cerebrospinal fluid test presented high total protein. Magnetic resonance image showed slight white matter increase in periventricular, semi-ov...

  13. [Cortical control of saccades].

    Science.gov (United States)

    Pierrot-Deseilligny, C

    1989-01-01

    Among saccades triggered by the cerebral cortex, visually guided saccades are the best known and their cortical control is reviewed here. Only two immediately supra-reticular structures are able to trigger saccades (whatever their type): the frontal eye fields (FEF) and the superior colliculus (SC). These structures control two parallel excitatory pathways, which can replace each other in the event of lesion. Experimental findings have suggested that the colliculo-reticular pathway would, in the normal state, play the main role in the triggering of reflexive visually guided saccades. Furthermore experimental and clinical data suggest that the SC would receive an excitatory afference from the posterior part of the intraparietal sulcus, which could be involved in the triggering of these saccades. The parietal lobe could influence the SC by increasing the pre-excitation due to the onset of the visual target. There are also inhibitory pathways which prevent saccades, in particular during fixation. Two groups of tonic neurons inhibit the excitatory pathways. These are the omnipause neurons and the neurons of the substantia nigra (pars reticulata), which project upon the premotor reticular formations and the SC respectively. The pathways projecting upon these 2 types of neurons are multiple and still little known. Nevertheless, some arguments suggest that the frontal lobe partly controls inhibition. These arguments are based on a somewhat disinhibited triggering of reflexive visually guided saccades in focal or degenerative (progressive supranuclear palsy) frontal lesions. The prefrontal cortex could be involved in inhibition control, and it could act functionally above the FEF. PMID:2682934

  14. A huge glandular odontogenic cyst occurring at posterior mandible

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Gi Chung; Han, Won Jeong; Kim, Eun Kyung [Dankook University College of Medicine, Seoul (Korea, Republic of)

    2004-12-15

    The glandular odontogenic cyst is a rare lesion described in 1987. It generally occurs at anterior region of mandible in adults over the age of 40 and has a slight tendency to recur. Histopathologically, a cystic cavity lined by a nonkeratinized, stratified squamous, or cuboidal epithelium varying in thickness is found including a superficial layer with glandular or pseudoglandular structures. A 21-year-old male visited Dankook University Dental Hospital with a chief complaint of swelling of the left posterior mandible. Radiographically, a huge multilocular radiolucent lesion involving impacted 3rd molar at the posterior mandible was observed. Buccolingual cortical expansion with partial perforation of buccal cortical bone was also shown. Histopathologically, this lesion was lined by stratified squamous epithelium with glandular structures in areas of plaque-like thickening. The final diagnosis was made as a glandular odontogenic cyst.

  15. A huge glandular odontogenic cyst occurring at posterior mandible

    International Nuclear Information System (INIS)

    The glandular odontogenic cyst is a rare lesion described in 1987. It generally occurs at anterior region of mandible in adults over the age of 40 and has a slight tendency to recur. Histopathologically, a cystic cavity lined by a nonkeratinized, stratified squamous, or cuboidal epithelium varying in thickness is found including a superficial layer with glandular or pseudoglandular structures. A 21-year-old male visited Dankook University Dental Hospital with a chief complaint of swelling of the left posterior mandible. Radiographically, a huge multilocular radiolucent lesion involving impacted 3rd molar at the posterior mandible was observed. Buccolingual cortical expansion with partial perforation of buccal cortical bone was also shown. Histopathologically, this lesion was lined by stratified squamous epithelium with glandular structures in areas of plaque-like thickening. The final diagnosis was made as a glandular odontogenic cyst.

  16. Anti-Correlated Cortical Networks of Intrinsic Connectivity in the Rat Brain

    OpenAIRE

    Schwarz, Adam J.; Gass, Natalia; Sartorius, Alexander; Risterucci, Celine; Spedding, Michael; Schenker, Esther; Meyer-Lindenberg, Andreas; Weber-Fahr, Wolfgang

    2013-01-01

    In humans, resting-state blood oxygen level-dependent (BOLD) signals in the default mode network (DMN) are temporally anti-correlated with those from a lateral cortical network involving the frontal eye fields, secondary somatosensory and posterior insular cortices. Here, we demonstrate the existence of an analogous lateral cortical network in the rat brain, extending laterally from anterior secondary sensorimotor regions to the insular cortex and exhibiting low-frequency BOLD fluctuations th...

  17. Análise da freqüência de trombofilia em pacientes com atrofia branca de Milian Frequency analysis of thrombophilia in patients with atrophie blanche

    Directory of Open Access Journals (Sweden)

    Aline Donati Jorge

    2007-02-01

    Full Text Available FUNDAMENTOS - Atrofia branca de Milian ou vasculopatia livedóide é entidade clinicopatológica rara, cuja patogênese não é completamente compreendida. OBJETIVOS - Avaliar casos de atrofia branca de Milian para verificar a prevalência de diversas trombofilias. MATERIAL E MÉTODOS - Quatorze pacientes foram submetidos a exames laboratoriais incluindo pesquisa de fator V (Leiden, protrombina mutante, dosagem de antitrombina, proteína S e C, pesquisa de anticorpos anticardiolipina e anticoagulante lúpico, dosagem de homocisteína e pesquisa da mutação da metilenotetraidrofolatoredutase. RESULTADOS - Dos nove doentes cujos critérios de inclusão foram preenchidos para análise da freqüência de trombofilia, foram encontrados quatro com fatores relacionados à trombofilia: deficiência da antitrombina (um caso, deficiência da proteína S (um caso, mutação da metilenotetraidrofolatoredutase com hiperhomocisteinemia (um caso e presença de anticorpo anticardiolipina (um caso. CONCLUSÃO - Apesar de este estudo não apresentar casuística que possibilite a comparação com a população geral, os dados sugerem a presença de eventos geradores de trombofilia nesses doentes, contribuindo para adoção sistemática de um protocolo de investigação de trombofilia nos doentes portadores de vasculopatia livedóide no Brasil.INTRODUCTION: Atrophie blanche, or livedoid vasculopathy, is a rare clinicopathological entity of unknown etiology. A "thrombo-occlusive process" theory has recently been accepted. OBJECTIVES: To search the presence of several thrombophilic abnormalities in patients with livedoid vasculopathy. METHODS: Fourteen patients were evaluated and tested for factor V Leiden, prothrombin 20210G/A variant, antithrombin, C and S proteins, anticardiolipin and lupus anticoagulant antibodies, homocysteine and methylenetetrahydrofolate reductase mutation. RESULTS: Nine patients met all criteria to be included in the analysis and four of

  18. Pure alexia and right hemiachromatopsia in posterior dementia.

    OpenAIRE

    Freedman, L; Costa, L.

    1992-01-01

    A 66 year old, right handed woman presented with pure alexia and right hemiachromatopsia (PARH) in the context of a posterior dementia. PARH was accompanied by prosopagnosia, 2-D object agnosia, and environmental agnosia. Visual fields were normal to confrontation testing. The pathological anatomy of PARH involves circumscribed damage to the lingual and fusiform gyri and paraventricular white matter of the left occipital cortex, two contiguous cortical regions functionally specialised for pro...

  19. Posterior instrumentation and fusion

    OpenAIRE

    Deniz Olgun, Z.; Yazici, Muharrem

    2012-01-01

    The purpose of surgery for adolescent idiopathic scoliosis, which characteristically includes thoracic hypokyphosis and all three columns of the spine, is the achievement of a balanced spine while preserving as many motion segments as possible and avoiding neurologic damage. Many approaches have been defined in the treatment of this common disease. Posterior-only surgery, instrumentation and fusion have become the preferred technique in many centers throughout the world due to simplicity of a...

  20. Suspensory Anterior Tibial Fixation in the Anatomic Transtibial Posterior Cruciate Ligament Reconstruction

    OpenAIRE

    Elazab, Ashraf; Lee, Yong Seuk; Kang, Seo Goo

    2016-01-01

    The transtibial technique is the most relevant among many surgical techniques for posterior cruciate ligament reconstruction, and many types of fixation devices are used for tibial fixation according to the technique and the length of the graft. However, bone density in the fixation areas should be taken into consideration when choosing the fixation device to achieve rigid and stable fixation. However, density is not a substantial issue for anteromedial cortical fixation using a cortical susp...

  1. Long-term results of extracapsular cataract extraction and posterior chamber intraocular lens insertion in Nepal.

    OpenAIRE

    Ruit, S; Robin, A L; Pokhrel, R. P.; Sharma, A.; DeFaller, J; Maguire, P T

    1991-01-01

    We performed a prospective study evaluating the 2-year success rate of extracapsular cataract surgery and posterior chamber IOL insertion performed in 610 eyes by an experienced surgeon in the Nepal Eye Hospital, Kathmandu, Nepal. All patients were followed for 2 years. All eyes underwent manual irrigation and aspiration of cortical materials with the insertion of a modified J-loop posterior chamber IOL. Almost one half of eyes had final uncorrected visual acuities of 20/50 or better. Devasta...

  2. Is cortical distribution of spectral power a stable individual characteristic?

    Science.gov (United States)

    Knyazev, Gennady G

    2009-05-01

    General understanding in EEG research is that cortical distribution of spectral power varies as a function of time, frequency, state, and experimental condition. There are findings, however, which show that individual-specific patterns of cortical spectral power distribution could be amazingly stable, at least in some experimental conditions. In this study two different experimental datasets were used to analyze stability and variability of individual pattern of cortical spectral power distribution across time, experimental conditions, and frequency bands. First experiment consisted of presentation of pictures of emotional facial expressions. Second experiment was an auditory stop-signal task. In both experiments a number of psychometric measures were obtained from each participant. It has been shown that in spite of high short-term variability, individual-specific patterns of cortical spectral power distribution are remarkably stable across frequency bands, long periods of time, and experimental conditions. These patterns are related to state and trait participant's characteristics. The antero-posterior spectral power gradient emerged as the most prominent feature associated with important personality dimensions. Relatively higher oscillatory activity in the frontal cortical region relates to female gender and Behavioral Inhibition tendencies. Relatively higher activity at posterior sites is associated with Extraversion. Significant differences in event-related spectral perturbations upon presentation of emotionally loaded stimuli were found between high and low antero-posterior gradient participants. These data show that cortical distribution of oscillatory activity may be seen as a relatively stable individual characteristic. Enhanced or diminished oscillatory activity of some cortical regions, such as the prefrontal cortex, may play an important role in organization of human behavior. PMID:19047002

  3. Posterior Urethral Strictures

    Directory of Open Access Journals (Sweden)

    Joel Gelman

    2015-01-01

    Full Text Available Pelvic fracture urethral injuries are typically partial and more often complete disruptions of the most proximal bulbar and distal membranous urethra. Emergency management includes suprapubic tube placement. Subsequent primary realignment to place a urethral catheter remains a controversial topic, but what is not controversial is that when there is the development of a stricture (which is usually obliterative with a distraction defect after suprapubic tube placement or urethral catheter removal, the standard of care is delayed urethral reconstruction with excision and primary anastomosis. This paper reviews the management of patients who suffer pelvic fracture urethral injuries and the techniques of preoperative urethral imaging and subsequent posterior urethroplasty.

  4. Posterior Urethral Strictures.

    Science.gov (United States)

    Gelman, Joel; Wisenbaugh, Eric S

    2015-01-01

    Pelvic fracture urethral injuries are typically partial and more often complete disruptions of the most proximal bulbar and distal membranous urethra. Emergency management includes suprapubic tube placement. Subsequent primary realignment to place a urethral catheter remains a controversial topic, but what is not controversial is that when there is the development of a stricture (which is usually obliterative with a distraction defect) after suprapubic tube placement or urethral catheter removal, the standard of care is delayed urethral reconstruction with excision and primary anastomosis. This paper reviews the management of patients who suffer pelvic fracture urethral injuries and the techniques of preoperative urethral imaging and subsequent posterior urethroplasty. PMID:26691883

  5. Posterior Tibial Tendon Transfer.

    Science.gov (United States)

    Shane, Amber M; Reeves, Christopher L; Cameron, Jordan D; Vazales, Ryan

    2016-01-01

    When performed correctly with the right patient population, a tibialis posterior muscle/tendon transfer is an effective procedure. Many different methods have been established for fixating the tendon, each of which has its' own indications. Passing through the interosseous membrane is the preferred and recommended method and should be used unless this is not possible. Good surgical planning based on patient needs and expectations, along with excellent postoperative care including early range of motion and physical therapy minimizes risk of complications and allows for the optimal outcome to be achieved. PMID:26590722

  6. Permanent Cortical Blindness After Bronchial Artery Embolization

    Energy Technology Data Exchange (ETDEWEB)

    Doorn, Colette S. van, E-mail: cvandoorn@gmail.com; De Boo, Diederick W., E-mail: d.w.deboo@amc.uva.nl [Academic Medical Centre, Department of Radiology (Netherlands); Weersink, Els J. M., E-mail: e.j.m.weersink@amc.uva.nl [Academic Medical Centre, Department of Pulmonology (Netherlands); Delden, Otto M. van, E-mail: o.m.vandelden@amc.uva.nl; Reekers, Jim A., E-mail: j.a.reekers@amc.uva.nl; Lienden, Krijn P. van, E-mail: k.p.vanlienden@amc.uva.nl [Academic Medical Centre, Department of Radiology (Netherlands)

    2013-12-15

    A 35-year-old female with a known medical history of cystic fibrosis was admitted to our institution for massive hemoptysis. CTA depicted a hypertrophied bronchial artery to the right upper lobe and showed signs of recent bleeding at that location. Bronchial artery embolization (BAE) was performed with gelfoam slurry, because pronounced shunting to the pulmonary artery was present. Immediately after BAE, the patient developed bilateral cortical blindness. Control angiography showed an initially not opacified anastomosis between the embolized bronchial artery and the right subclavian artery, near to the origin of the right vertebral artery. Cessation of outflow in the bronchial circulation reversed the flow through the anastomosis and allowed for spill of embolization material into the posterior circulation. Unfortunately the cortical blindness presented was permanent.

  7. Permanent Cortical Blindness After Bronchial Artery Embolization

    International Nuclear Information System (INIS)

    A 35-year-old female with a known medical history of cystic fibrosis was admitted to our institution for massive hemoptysis. CTA depicted a hypertrophied bronchial artery to the right upper lobe and showed signs of recent bleeding at that location. Bronchial artery embolization (BAE) was performed with gelfoam slurry, because pronounced shunting to the pulmonary artery was present. Immediately after BAE, the patient developed bilateral cortical blindness. Control angiography showed an initially not opacified anastomosis between the embolized bronchial artery and the right subclavian artery, near to the origin of the right vertebral artery. Cessation of outflow in the bronchial circulation reversed the flow through the anastomosis and allowed for spill of embolization material into the posterior circulation. Unfortunately the cortical blindness presented was permanent

  8. Posterior glenoid rim deficiency in recurrent (atraumatic) posterior shoulder instability

    International Nuclear Information System (INIS)

    Objective. To assess the shape of the posterior glenoid rim in patients with recurrent (atraumatic) posterior instability.Design and patients. CT examinations of 15 shoulders with recurrent (atraumatic) posterior instability were reviewed in masked fashion with regard to abnormalities of the glenoid shape, specifically of its posterior rim. The glenoid version was also assessed. The findings were compared with the findings in 15 shoulders with recurrent anterior shoulder instability and 15 shoulders without instability. For all patients, surgical correlation was available.Results. Fourteen of the 15 (93%) shoulders with recurrent (atraumatic) posterior shoulder instability had a deficiency of the posteroinferior glenoid rim. In patients with recurrent anterior instability or stable shoulders such deficiencies were less common (60% and 73%, respectively). The craniocaudal length of the deficiencies was largest in patients with posterior instability. When a posteroinferior deficiency with a craniocaudal length of 12 mm or more was defined as abnormal, sensitivity and specificity for diagnosing recurrent (atraumatic) posterior instability were 86.7% and 83.3%, respectively. There was a statistically significant difference in glenoid version between shoulders with posterior instability and stable shoulders (P=0.01).Conclusion. Recurrent (atraumatic) posterior shoulder instability should be considered in patients with a bony deficiency of the posteroinferior glenoid rim with a craniocaudal length of more than 12 mm. (orig.)

  9. Wireless cortical implantable systems

    CERN Document Server

    Majidzadeh Bafar, Vahid

    2013-01-01

    Wireless Cortical Implantable Systems examines the design for data acquisition and transmission in cortical implants. The first part of the book covers existing system-level cortical implants, as well as future devices. The authors discuss the major constraints in terms of microelectronic integration. The second part of the book focuses on system-level as well as circuit and system level solutions to the development of ultra low-power and low-noise microelectronics for cortical implants. Existing solutions are presented and novel methods and solutions proposed. The third part of the book focuses on the usage of digital impulse radio ultra wide-band transmission as an efficient method to transmit cortically neural recorded data at high data-rate to the outside world. Original architectural and circuit and system solutions are discussed.

  10. [Infection of a total knee prosthesis revealed by an abscess of the posterior leg compartment. A case report].

    Science.gov (United States)

    Duranthon, L D; Baaklini, M; Grimberg, J; Vandenbussche, E; Augereau, B

    2001-04-01

    We report a case of infection of a non-cemented total knee prosthesis that led to abscess formation in the posterior compartment of the leg. This case illustrates the deleterious effect of screws used to fix the non-cemented articular surface of the tibia. Infection, like osteolysis due to polyethylene granuloma, can develop along the screw tract and reach the posterior compartment, especially when the screw protrudes through the posterior cortical of the tibia. Diffusion of an intra-articular event into the posterior compartment should be suspected in patients with a total knee prosthesis who experience calf pain. PMID:11319432

  11. The development of cortical sensitivity to visual word forms.

    Science.gov (United States)

    Ben-Shachar, Michal; Dougherty, Robert F; Deutsch, Gayle K; Wandell, Brian A

    2011-09-01

    The ability to extract visual word forms quickly and efficiently is essential for using reading as a tool for learning. We describe the first longitudinal fMRI study to chart individual changes in cortical sensitivity to written words as reading develops. We conducted four annual measurements of brain function and reading skills in a heterogeneous group of children, initially 7-12 years old. The results show age-related increase in children's cortical sensitivity to word visibility in posterior left occipito-temporal sulcus (LOTS), nearby the anatomical location of the visual word form area. Moreover, the rate of increase in LOTS word sensitivity specifically correlates with the rate of improvement in sight word efficiency, a measure of speeded overt word reading. Other cortical regions, including V1, posterior parietal cortex, and the right homologue of LOTS, did not demonstrate such developmental changes. These results provide developmental support for the hypothesis that LOTS is part of the cortical circuitry that extracts visual word forms quickly and efficiently and highlight the importance of developing cortical sensitivity to word visibility in reading acquisition. PMID:21261451

  12. Presentación de un caso clínico de atrofia multisistémica y actualización de criterios diagnósticos: A clinical case presentation

    OpenAIRE

    Alexis Soto Lavastida; Gloria Lara Fernández; Enrique Michel Esteban; Juan Carlos Llibre Guerra

    2011-01-01

    La atrofia multisistèmica constituye un trastorno neurodegenerativo esporádico de etiología no precisada que se caracteriza por parkinsonismo, trastornos cerebelosos, disfunción autonómica y piramidalismo; los hallazgos patológicos comprenden pérdida celular y gliosis en las neuronas estriatonígricas, olivopontocerebelosas y autonómicas; y la presencia de inclusiones intracitoplasmáticas oligodendrogliales y neuronales, ubiquitina, tau y alfasinucleína positivas. Afecta tanto a hombres como a...

  13. La inhibición de las E3 ubiquitin-ligasas, a través de NF-кB y p38, previene la atrofia muscular. Utilidad de la indometacina y el alopurinol

    OpenAIRE

    Ferrando Forés, Beatriz

    2014-01-01

    La atrofia del músculo esquelético se produce como consecuencia de múltiples enfermedades y condiciones crónicas. Así mismo, reduce las opciones de tratamiento y los resultados clínicos positivos, comprometiendo la calidad de vida por un aumento de la morbilidad y la mortalidad. La producción de unos niveles mínimos de fuerza muscular es un requisito para la realización de actividades de la vida diaria tales como levantarse de una silla o subir escaleras. Una persona joven sana es capaz de de...

  14. Decrease of Prefrontal-Posterior EEG Coherence: Loose Control during Social-Emotional Stimulation

    Science.gov (United States)

    Reiser, Eva M.; Schulter, Gunter; Weiss, Elisabeth M.; Fink, Andreas; Rominger, Christian; Papousek, Ilona

    2012-01-01

    In two experiments we aimed to investigate if individual differences in state-dependent decreases or increases of EEG coherence between prefrontal and posterior cortical regions may be indicative of a mechanism modulating the impact social-emotional information has on an individual. Two independent samples were exposed to an emotional stimulation…

  15. PROSPECTIVE RANDOMISED COMPARATIVE STUDY OF THE EFFECTS OF 0.06% TRYPAN BLUE DYE AS AGAINST 0.03% TRYPAN BLUE DYE AFTER CORTICAL CLEAVING HYDRO-DISSECTION IN AN EFFORT TO IMPEDE THE FORMATION OF POSTERIOR CAPSULAR OPACIFICATION(PCO)

    OpenAIRE

    Vishnu S.; Mayuresh P.; Ajay; Anuj; Sethi

    2014-01-01

    PURPOSE: Effect of 0.06% Trypan blue dye as against 0.03% Trypan blue dye after cortical cleaving hydro-dissection in eyes undergoing phacoemulsification. SETTING: V. M. M. C & Safdarjung hospital, New Delhi (Tertiary health care centre). DESIGN: Prospective randomised double-blind (Patient and examiner blind) comparative study. MATERIALS AND METHODS : 150 eyes of 150 patients undergoing phacoemulsification were randomized to have 0.2mL of Trypan blue dye 0.06%(Group A) or...

  16. Development of Cortical Interneurons

    OpenAIRE

    Chu, Jianhua; Anderson, Stewart A.

    2014-01-01

    Inhibitory local circuit neurons (LCNs), often called interneurons, have vital roles in the development and function of cortical networks. Their inhibitory influences regulate both the excitability of cortical projection neurons on the level of individual cells, and the synchronous activity of projection neuron ensembles that appear to be a neural basis for major aspects of cognitive processing. Dysfunction of LCNs has been associated with neurological and psychiatric diseases, such as epilep...

  17. Multiple system atrophy: clinical-radiological correlation. Report of two cases Atrofia de múltiplos sistemas: correlação clínico-radiológica. Estudo de dois casos

    Directory of Open Access Journals (Sweden)

    Adolfo V. de Albuquerque

    2007-06-01

    Full Text Available Multiple system atrophy (MSA is a sporadic, neurodegenerative disorder, clinically characterized by parkinsonian, autonomic, cerebellar and pyramidal signs. We describe two patients showing different presentations of the same disease. The patient on case 1 presents features of MSA-C or olivopontocerebellar atrophy with the pontine "cross sign" on brain MRI. The second case reports a patient presenting MSA-P or striatonigral degeneration and the brain MRI shows lenticular nucleus sign alteration. We think that brain MRI might increase the accuracy diagnostic of MSA.A atrofia de múltiplos sistemas (AMS é uma doença neurodegenerativa esporádica caracterizada clinicamente por diferentes combinações de sinais parkinsonianos, autonômicos, cerebelares e piramidais. Descrevemos dois pacientes apresentando diferentes formas clínicas da mesma afecção. O caso 1 tem características da AMS-C ou atrofia olivopontocerebelar, apresentando na ressonância magnética (RM o "sinal da cruz" na ponte. Já o caso 2 tem AMS-P ou degeneração nigro-estriatal, a RM mostra alteração do sinal no núcleo lentiforme entre outras alterações. Acreditamos que a RM cerebral possa contribuir para o melhor diagnóstico da AMS.

  18. A spatiotemporal signature of cortical pain relief by tactile stimulation: An MEG study.

    Science.gov (United States)

    Hayamizu, Mariko; Hagiwara, Koichi; Hironaga, Naruhito; Ogata, Katsuya; Hoka, Sumio; Tobimatsu, Shozo

    2016-04-15

    Recently, the cortical mechanisms of tactile-induced analgesia have been investigated; however, spatiotemporal characteristics have not been fully elucidated. The insular-opercular region integrates multiple sensory inputs, and nociceptive modulation by other sensory inputs occurs in this area. In this study, we focused on the insular-opercular region to characterize the spatiotemporal signature of tactile-induced analgesia using magnetoencephalography in 11 healthy subjects. Aδ (intra-epidermal electrical stimulation) inputs were modified by Aβ (mechanical tactile stimulation) selective stimulation, either independently or concurrently, to the right forearm. The optimal inter-stimulus interval (ISI) for cortical level modulation was determined after comparing the 40-, 60-, and 80-ms ISI conditions, and the calculated cortical arrival time difference between Aδ and Aβ inputs. Subsequently, we adopted a 60-ms ISI for cortical modulation and a 0-ms ISI for spinal level modulation. Source localization using minimum norm estimates demonstrated that pain-related activity was located in the posterior insula, whereas tactile-related activity was estimated in the parietal operculum. We also found significant inhibition of pain-related activity in the posterior insula due to cortical modulation. In contrast, spinal modulation was observed both in the posterior insula and parietal operculum. Subjective pain, as evaluated by the visual analog scale, also showed significant reduction in both conditions. Therefore, our results demonstrated that the multisensory integration within the posterior insula plays a key role in tactile-induced analgesia. PMID:26854558

  19. Hierarchical organization of long-range circuits in the olfactory cortices

    OpenAIRE

    Yang, Weiguo; Sun, Qian-Quan

    2015-01-01

    How sensory information is processed within olfactory cortices is unclear. Here, we examined long-range circuit wiring between different olfactory cortical regions of acute mouse brain slices using a channelrhodopsin-2 (ChR2)-based neuronal targeting approach. Our results provide detailed information regarding the synaptic properties of the reciprocal long-range monosynaptic glutamatergic projections (LRMGP) between and within anterior piriform cortex (aPC), posterior piriform cortex (pPC), a...

  20. Missed isolated posterior malleolar fractures

    OpenAIRE

    Ozler, Turhan; Guven, Melih; Onal, Ayberk; Ulucay, Cagatay; Beyzadeoglu, Tahsin; Altintas, Faik

    2014-01-01

    Objective:The aim of this study was to evaluate the injury mechanism and clinical and radiological results of the patients with isolated posterior malleolar fracture.Methods: Seven patients (5 male, 2 female; mean age: 32 years; range: 23-40) with a missed isolated posterior malleolar fracture were included in the study. All patients had initially been examined for an ankle sprain in the emergency room, where the initial plain radiographs did not show any abnormality. Due to the long lasting ...

  1. Estimulação elétrica neuromuscular em cães com atrofia muscular induzida Neuromuscular electric stimulation in dogs with induced muscle atrophy

    Directory of Open Access Journals (Sweden)

    C. Pelizzari

    2008-02-01

    Full Text Available Empregou-se a estimulação elétrica neuromuscular (EENM de baixa freqüência no músculo quadríceps femoral de cães com atrofia induzida e avaliou-se a ocorrência de ganho de massa nessa musculatura. Foram utilizados oito cães com pesos entre 15 e 30kg, distribuídos aleatoriamente em dois grupos denominados de I ou controle e II ou tratado. A articulação femorotibiopatelar esquerda foi imobilizada por 30 dias pelo método de transfixação percutânea tipo II, com retirada de aparelho de imobilização após esse período. Decorridas 48 horas da remoção, foi realizada a EENM nos cães do grupo II, cinco vezes por semana, com intervalo de 24 horas cada sessão, pelo período de 60 dias. Foram avaliadas a circunferência da coxa, a goniometria do joelho, a análise clínica da marcha, as enzimas creatina-quinase (CK e aspartato-amino-transferase (AST e a morfometria das fibras musculares em cortes transversais do músculo vasto lateral colhido mediante biópsia muscular. A EENM foi empregada no músculo quadríceps femoral na freqüência de 50Hz, duração de pulso de 300 milisegundos e relação de tempo on/off de 1:2. Quanto à morfometria das fibras do músculo vasto lateral, no grupo tratado houve aumento significativo (PLow frequency neuromuscular electrical stimulation (NMES was used on the femoral quadriceps of dogs with induced muscular atrophy and the occurrence of gain in mass in these muscles was evaluated. Eight dogs from 15 to 30kg were randomly distributed in two groups named I, or control; and II, or treated. For the induction of muscular atrophy, the left femoral-tibial-patellar joint was immobilized for 30 days by percutaneous transfixation type II. After 30 days, the immobilization device was removed. The NMES treatment began 48 hours after the removal of the immobilization device of the dogs of group II, and it was carried out five times per week with an interval of 24 hours between each session, for 60 days. The

  2. Focal cortical dysplasia – review

    OpenAIRE

    Kabat, Joanna; Król, Przemysław

    2012-01-01

    Summary Focal cortical dysplasia is a malformation of cortical development, which is the most common cause of medically refractory epilepsy in the pediatric population and the second/third most common etiology of medically intractable seizures in adults. Both genetic and acquired factors are involved in the pathogenesis of cortical dysplasia. Numerous classifications of the complex structural abnormalities of focal cortical dysplasia have been proposed – from Taylor et al. in 1971 to the last...

  3. Posterior cruciate ligament reconstruction by means of tibial tunnel: anatomical study on cadavers for tunnel positioning☆☆☆

    OpenAIRE

    Antônio Altenor Bessa de Queiroz; César Janovsky; Carlos Eduardo da Silveira Franciozi; Leonardo Addêo Ramos; Geraldo Sérgio Mello Granata Junior; Marcos Vinicius Malheiros Luzo; Moises Cohen

    2014-01-01

    Objective:To determine the reference points for the exit of the tibial guidewire in relation to the posterior cortical bone of the tibia.Methods:Sixteen knees from fresh cadavers were used for this study. Using a viewing device and a guide marked out in millimeters, three guidewires were passed through the tibia at 0, 10 and 15 mm distally in relation to the posterior crest of the tibia. Dissections were performed and the region of the center of the tibial insertion of the posterior cruciate ...

  4. Posterior reversible encephalopathy syndrome in a hypertensive patient with renal failure.

    Science.gov (United States)

    Aatif, T; El Farouki, M R; Benyahia, M

    2016-03-01

    Posterior reversible encephalopathy syndrome (PRES) is a clinical and neuroimaging entity characterized by headache, visual field deficits, changes in mentation and seizures, and by typical neuro-imaging features such as areas of sub-cortical edema, occasionally cortical, involving predominantly the occipital and parietal lobes of both hemispheres. Hypertension, uremia, immunosuppressive drugs neurotoxicity, preeclampsia or eclampsia, renal disease, and sepsis are the most common etiologies of PRES. Less common, it has been described in the setting of autoimmune disease. We report a case of PRES which was associated with hypertensive crisis in a patient with renal failure. Antihypertensive therapy and hemodialysis resulted in complete recovery. PMID:26997402

  5. Posterior reversible encephalopathy syndrome in a hypertensive patient with renal failure

    Directory of Open Access Journals (Sweden)

    T Aatif

    2016-01-01

    Full Text Available Posterior reversible encephalopathy syndrome (PRES is a clinical and neuroimaging entity characterized by headache, visual field deficits, changes in mentation and seizures, and by typical neuro-imaging features such as areas of sub-cortical edema, occasionally cortical, involving predominantly the occipital and parietal lobes of both hemispheres. Hypertension, uremia, immunosuppressive drugs neurotoxicity, preeclampsia or eclampsia, renal disease, and sepsis are the most common etiologies of PRES. Less common, it has been described in the setting of autoimmune disease. We report a case of PRES which was associated with hypertensive crisis in a patient with renal failure. Antihypertensive therapy and hemodialysis resulted in complete recovery.

  6. Uso de Polietigel® intra-orbitário em paciente com atrofia hemifacial progressiva: relato de caso Use of intraorbital Polietigel® in a patient with progressive hemifacial atrophy: case report

    OpenAIRE

    Amilton de Almeida Sampaio Junior; Fabrício Kafuri; Silvana Artioli Schellini; Romualdo Rossa

    2004-01-01

    O objetivo é relatar o caso de portadora de atrofia hemifacial progressiva, atendida na Faculdade de Medicina de Botucatu-UNESP: A paciente do sexo feminino, 43 anos, branca, queixava-se de "afundamento" progressivo do olho esquerdo e região orbitária há aproximadamente 10 anos, com dor na região periorbitária ipsilateral e diminuição da acuidade visual. O exame tomográfico confirmou a hipótese e o tratamento foi feito com injeção de Polietigel® na órbita, com bom resultado estético e melhora...

  7. Ressonância magnética na mielopatia associada ao HTLV-I: Leucoencefalopatia e atrofia medular Magnetic resonance in HTLV-I associated myelopathy: leukoencephalopathy and spinal cord atrophy

    OpenAIRE

    Ana Claudia Ferraz; Alberto Alain Gabbai; Nitamar Abdala; Roberto Gomes Nogueira

    1997-01-01

    Lesões na substância branca cerebral e atrofia medular têm sido descritas em pacientes com mielopatia associada ao HTLV-I (MAH). A freqüência e a importância clínica destes achados ainda não são totalmente conhecidas. Vinte e nove pacientes foram estudados por ressonância magnética (RM) do crânio e da coluna. Imagens com hipersinal em T2 na substância branca, de diâmetro igual ou superior a 3 mm foram consideradas anormais. O tamanho da medula foi avaliado usando índice por nós denominado "ín...

  8. Imaging analysis of spiral fractures of distal third of the tibia fracture with occult posterior malleolar fracture

    International Nuclear Information System (INIS)

    Objective: To analyze the diagnostic value of MSCT and MRI in detecting the distal third of tibia shaft fracture complicated with occult posterior malleolar fracture. Methods: One hundred and fifty-one patients with the distal third of tibia shaft spiral fracture underwent X-ray examination. For patients without posterior malleolar fracture on X-ray, MSCT and MR imaging were further performed. A binomial test was used to evaluate the significance of the differences between MSCT and MRI in the detection of posterior malleolar fractures and cortical involvement. Results: A total of 126 (83.4%) in 151 tibia shaft fracture were found to be associated with posterior malleolar fracture. Twenty-seven (21.4%) cases with posterior malleolar fracture were detected on X-ray. MSCT and MR examination were performed in 124 cases. Ninety-nine posterior malleolar occult fractures were detected on MRI, which included 81 cases showed on MSCT. The sensitivity, specificity and accuracy of posterior malleolar occult fracture on MRI were 100% (99/99), 100% (25/25) and 100% (124/124), while they were 81.8% (81/99), 100% (25/25) and 85.5% (106/124) for MSCT respectively. The accuracy of posterior malleolar occult fracture on MRI was significant higher than MSCT (Z=2.56, P=0.01). Seventy-eight cortical fractures were found on MSCT among 99 posterior malleolar occult fractures, while 51 fractures were found on MRI. The sensitivity, specificity and accuracy of cortical fracture involvement were 100% (78/78), 100% (21/21) and 100% ( 99/99) for MSCT, while they were 65.4% (51/78), 100% (21/21) and 72.7% (72/99) for MRI respectively. The accuracy of cortical fracture involvement on MSCT was significant higher than MRI (Z=4.02, P=0.00). Conclusions: MRI has a higher accuracy than MSCT in detecting the distal third of tibia shaft fracture complicated with occult posterior malleolar fracture, while MSCT has a higher accuracy than MRI in detecting cortical fracture involvement. (authors)

  9. Spreading Photoparoxysmal EEG Response is Associated with an Abnormal Cortical Excitability Pattern

    Science.gov (United States)

    Siniatchkin, Michael; Groppa, Sergey; Jerosch, Bettina; Muhle, Hiltrud; Kurth, Christoph; Shepherd, Alex J.; Siebner, Hartwig; Stephani, Ulrich

    2007-01-01

    Photosensitivity or photoparoxysmal response (PPR) is a highly heritable electroencephalographic trait characterized by an abnormal cortical response to intermittent photic stimulation (IPS). In PPR-positive individuals, IPS induces spikes, spike-waves or intermittent slow waves. The PPR may be restricted to posterior visual areas (i.e. local PPR…

  10. Bilateral posterior cerebral artery infarction

    OpenAIRE

    Ryan, Davinia; Murphy, Sinead M; Hennessey, Michael J

    2010-01-01

    We report the case of a 70-year-old man who presented with short-term memory impairment and a homonymous left inferior quadrantanopia secondary to simultaneous bilateral posterior cerebral artery (PCA) territory infarction. As in more than a quarter of cases of PCA

  11. Stereolithography for Posterior Fossa Cranioplasty

    OpenAIRE

    Agner, Celso; Dujovny, Manuel; Evenhouse, Raymond; Fady T. Charbel; Sadler, Lewis

    1998-01-01

    Posterior fossa cranioplasty has been suggested for improvement of neurological symptoms following craniectomy. However, there is no particular recommendation in the literature about techniques for prosthesis manufacture and implantation. We report our experience using rapid prototyping technology and stereolithography for pre-surgical implant design and production of cranioplasties.

  12. Prefrontal, posterior parietal and sensorimotor network activity underlying speed control during walking

    Directory of Open Access Journals (Sweden)

    Thomas C Bulea

    2015-05-01

    Full Text Available Accumulating evidence suggests cortical circuits may contribute to control of human locomotion. Here, noninvasive electroencephalography (EEG recorded from able-bodied volunteers during a novel treadmill walking paradigm was used to assess neural correlates of walking. A systematic processing method, including a recently developed subspace reconstruction algorithm, reduced movement-related EEG artifact prior to independent component analysis and dipole source localization. We quantified cortical activity while participants tracked slow and fast target speeds across two treadmill conditions: an active mode that adjusted belt speed based on user movements and a passive mode reflecting a typical treadmill. Our results reveal frequency specific, multi-focal task related changes in cortical oscillations elicited by active walking. Low γ band power, localized to the prefrontal and posterior parietal cortices, was significantly increased during double support and early swing phases, critical points in the gait cycle since the active controller adjusted speed based on pelvis position and swing foot velocity. These phasic γ band synchronizations provide evidence that prefrontal and posterior parietal networks, previously implicated in visuo-spatial and somotosensory integration, are engaged to enhance lower limb control during gait. Sustained μ and β band desynchronization within sensorimotor cortex, a neural correlate for movement, was observed during walking thereby validating our methods for isolating cortical activity. Our results also demonstrate the utility of EEG recorded during locomotion for probing the multi-regional cortical networks which underpin its execution. For example, the cortical network engagement elicited by the active treadmill suggests that it may enhance neuroplasticity for more effective motor training.

  13. Avaliação dos resultados do tratamento cirúrgico da escoliose na atrofia muscular espinhal tipo 2 Evaluación de los resultados del tratamiento quirúrgico de la escoliosis en la atrofia muscular espinal tipo 2 Results evaluation of surgical treatment of scoliosis in spinal muscular atrophy type 2

    Directory of Open Access Journals (Sweden)

    Luiz Eduardo Munhoz da Rocha

    2011-01-01

    Full Text Available OBJETIVO: Avaliar o resultado do tratamento cirúrgico da escoliose em pacientes com atrofia muscular espinhal (AME tipo 2. MÉTODO: Estudo retrospectivo com 12 pacientes portadores de AME tipo 2 submetidos à artrodese e instrumentação para correção da escoliose com mais de dois anos de seguimento. Foi avaliado o grau e percentual de correção da deformidade e da obliquidade pélvica no pós-operatório e a perda na última avaliação, além das complicações e o impacto do tratamento sobre a função respiratória. RESULTADOS: O seguimento médio foi de 77,5 meses (6,4 anos ± 58,9 meses (4,9 anos, o ângulo de Cobb pré-operatório médio foi de 76,1° ± 31,7° (35° a 144° e no pós-operatório de 29,5° ± 23,2° (5° a 90°, com a correção média de 46,6° (61,29%. A obliquidade pélvica média no pré-operatório foi de 15,1° ± 13,3° (variação de 0° a 37°, e no pós-operatório de 8,5° ± 9,9° (variação de 0° a 30°, com uma correção média de 6,5° (43,37%. Cinco pacientes tiveram complicações (41,6%. A Capacidade Ventilatória Forçada (CVF média pré-operatória foi de 62,9% ± 38,6% (variação de 23,3% a 89% e de 45,9% ± 25,0% (variação de 15% a 86,2%, na última avaliação. O declínio foi de 17% da capacidade vital, com redução de 2,4% por ano de seguimento. CONCLUSÕES: O tratamento cirúrgico da escoliose em pacientes com AME permite corrigir a obliquidade pélvica e restabelecer o balanço sagital e coronal liberando as mãos para as atividades da vida diária. A função pulmonar foi afetada positivamente pelo tratamento.OBJETIVO: Evaluar los resultados del tratamiento quirúrgico de la escoliosis en pacientes con atrofia muscular espinal (AME de tipo 2. MÉTODOS: Estudio retrospectivo de 12 pacientes con atrofia muscular espinal tipo 2 que fueron sometidos a artrodesis e instrumentación para la corrección de la escoliosis, con más de dos años de seguimiento. En la última evaluación, se

  14. Focal cortical hypoperfusion in corticobasal degeneration demonstrated by three-dimensional surface display with {sup 123}I-IMP: a possible cause of apraxia

    Energy Technology Data Exchange (ETDEWEB)

    Okuda, B. [5. Department of Internal Medicine, Hyogo College of Medicine, Nishinomiya (Japan); Tachibana, H. [5. Department of Internal Medicine, Hyogo College of Medicine, Nishinomiya (Japan); Takeda, M. [5. Department of Internal Medicine, Hyogo College of Medicine, Nishinomiya (Japan); Kawabata, K. [5. Department of Internal Medicine, Hyogo College of Medicine, Nishinomiya (Japan); Sugita, M. [5. Department of Internal Medicine, Hyogo College of Medicine, Nishinomiya (Japan); Fukuchi, M. [Department of Nuclear Medicine, Hyogo College of Medicine, Nishinomiya (Japan)

    1995-11-01

    To clarify cortical lesions responsible for apraxia in corticobasal degeneration (CBD), we reconstructed three-dimensional surface images from single-photon emission computed tomography (SPECT) data with N-isopropyl-p[I-123]-iodoamphetamine in two patients with CBD. Both had limb-kinetic apraxia (LKA) and one also had constructional apraxia (CA). Both showed asymmetrical cortical hypoperfusion in the perirolandic area. The patient with CA had unilateral hypoperfusion in the posterior parietal area. Thus, cortical hypoperfusion in the perirolandic area corresponded to LKA, and that in the posterior parietal area to CA. (orig.). With 4 figs.

  15. Focal cortical hypoperfusion in corticobasal degeneration demonstrated by three-dimensional surface display with 123I-IMP: a possible cause of apraxia

    International Nuclear Information System (INIS)

    To clarify cortical lesions responsible for apraxia in corticobasal degeneration (CBD), we reconstructed three-dimensional surface images from single-photon emission computed tomography (SPECT) data with N-isopropyl-p[I-123]-iodoamphetamine in two patients with CBD. Both had limb-kinetic apraxia (LKA) and one also had constructional apraxia (CA). Both showed asymmetrical cortical hypoperfusion in the perirolandic area. The patient with CA had unilateral hypoperfusion in the posterior parietal area. Thus, cortical hypoperfusion in the perirolandic area corresponded to LKA, and that in the posterior parietal area to CA. (orig.). With 4 figs

  16. Cortical ependymoma or monomorphous angiocentric glioma?

    Science.gov (United States)

    Lum, Dennis J; Halliday, William; Watson, Michael; Smith, Andrew; Law, Andrew

    2008-02-01

    Ependymoma is the third most common childhood intracranial tumor after medulloblastoma and pilocytic astrocytoma. Most ependymomas occur in the posterior fossa and spinal cord but only five cases confined to the cerebral cortex have been reported. The current case is a 5-year-old boy with a somewhat ill-defined cortical tumor diagnosed as pilocytic astrocytoma on biopsy, and treated with radiotherapy. Nine years later, resection of the essentially unaltered tumor was performed for treatment of intractable seizures. Histologically, the tumor had some areas with the typical appearance of ependymoma as well other areas which contained piloid cells. There was also evidence of focal infiltrative growth. These findings bore resemblance to a recently described entity monomorphous angiocentric glioma/angiocentric neuroepithelial tumor, which combines features of ependymoma with pilocytic and diffuse astrocytomas. Both cortical ependymomas and angiocentric monomorphous glioma/angiocentric neuroepithelial tumor appear to be low-grade tumors although their rarity makes accurate prognosis problematic. The current case has features of both entities, suggesting they may be closely related. PMID:18021197

  17. Developmental refinement of cortical systems for speech and voice processing.

    Science.gov (United States)

    Bonte, Milene; Ley, Anke; Scharke, Wolfgang; Formisano, Elia

    2016-03-01

    Development typically leads to optimized and adaptive neural mechanisms for the processing of voice and speech. In this fMRI study we investigated how this adaptive processing reaches its mature efficiency by examining the effects of task, age and phonological skills on cortical responses to voice and speech in children (8-9years), adolescents (14-15years) and adults. Participants listened to vowels (/a/, /i/, /u/) spoken by different speakers (boy, girl, man) and performed delayed-match-to-sample tasks on vowel and speaker identity. Across age groups, similar behavioral accuracy and comparable sound evoked auditory cortical fMRI responses were observed. Analysis of task-related modulations indicated a developmental enhancement of responses in the (right) superior temporal cortex during the processing of speaker information. This effect was most evident through an analysis based on individually determined voice sensitive regions. Analysis of age effects indicated that the recruitment of regions in the temporal-parietal cortex and posterior cingulate/cingulate gyrus decreased with development. Beyond age-related changes, the strength of speech-evoked activity in left posterior and right middle superior temporal regions significantly scaled with individual differences in phonological skills. Together, these findings suggest a prolonged development of the cortical functional network for speech and voice processing. This development includes a progressive refinement of the neural mechanisms for the selection and analysis of auditory information relevant to the ongoing behavioral task. PMID:26777479

  18. Antero-Posterior EEG Spectral Power Gradient as a Correlate of Extraversion and Behavioral Inhibition

    OpenAIRE

    Knyazev, Gennady G.

    2010-01-01

    Several studies have shown that individual-specific patterns of cortical spectral power distribution are relatively stable across time and experimental conditions. The antero-posterior EEG spectral power gradient (APSPG) emerged as the most prominent feature associated with important personality characteristics. In this study this phenomenon is further investigated in relation to its stability and association with different personality traits. It has been shown that APSPG is generally more pr...

  19. Posterior reversible encephalopathy syndrome after depletive lumbar puncture: a case report

    OpenAIRE

    Grelat, Michael; Debaux, Jean-Baptiste; Sautreaux, Jean-Louis

    2014-01-01

    Introduction Posterior reversible encephalopathy syndrome is a rare entity. Its pathophysiology is still poorly understood. Case presentation We report the case of a 69-year-old White European woman who presented complete and proportional right hemiplegia, confusion, deviation of her head and eyes to the right, cortical blindness, and generalized tonic-clonic seizure 12 hours following a depletive lumbar puncture. Emergency cerebral magnetic resonance imaging showed bioccipital and left-side ...

  20. Analysis of Cortical Morphometric Variability Using Labeled Cortical Distance Maps

    OpenAIRE

    Ceyhan, E.; Nishino, T.; Botteron, K. N.; Miller, M. I.; Ratnanather, J. T.

    2015-01-01

    Morphometric differences in the anatomy of cortical structures are associated with neuro-developmental and neuropsychiatric disorders. Such differences can be quantized and detected by a powerful tool called Labeled Cortical Distance Map (LCDM). The LCDM method pro-vides distances of labeled gray matter (GM) voxels from the GM/white matter (WM) surface for specific cortical structures (or tissues). Here we describe a method to analyze morphometric variability in the particular tissue using LC...

  1. Visual attention in posterior stroke

    DEFF Research Database (Denmark)

    Fabricius, Charlotte; Petersen, Anders; Iversen, Helle K;

    Objective: Impaired visual attention is common following strokes in the territory of the middle cerebral artery, particularly in the right hemisphere. However, attentional effects of more posterior lesions are less clear. The aim of this study was to characterize visual processing speed and...... apprehension span following posterior cerebral artery (PCA) stroke. We also relate these attentional parameters to visual word recognition, as previous studies have suggested that reduced visual speed and span may explain pure alexia. Methods: Nine patients with MR-verified focal lesions in the PCA......-territory (four left PCA; four right PCA; one bilateral, all >1 year post stroke) were compared to 25 controls using single case statistics. Visual attention was characterized by a whole report paradigm allowing for hemifield-specific speed and span measurements. We also characterized visual field defects and...

  2. Bilateral posterior cerebral artery infarction.

    Science.gov (United States)

    Ryan, Davinia; Murphy, Sinead M; Hennessey, Michael J

    2010-01-01

    We report the case of a 70-year-old man who presented with short-term memory impairment and a homonymous left inferior quadrantanopia secondary to simultaneous bilateral posterior cerebral artery (PCA) territory infarction. As in more than a quarter of cases of PCA infarction, no aetiological cause was identified. Unlike the transient nature of symptoms in some cases following unilateral infarction, his deficits persisted on 2-month follow-up. PMID:22798298

  3. Minimally Invasive Posterior Hamstring Harvest

    OpenAIRE

    Wilson, Trent J.; Lubowitz, James H.

    2013-01-01

    Autogenous hamstring harvesting for knee ligament reconstruction is a well-established standard. Minimally invasive posterior hamstring harvest is a simple, efficient, reproducible technique for harvest of the semitendinosus or gracilis tendon or both medial hamstring tendons. A 2- to 3-cm longitudinal incision from the popliteal crease proximally, in line with the semitendinosus tendon, is sufficient. The deep fascia is bluntly penetrated, and the tendon or tendons are identified. Adhesions ...

  4. Posterior asymmetry and idiopathic scoliosis

    CERN Document Server

    Rousie, D L; Berthoz, A

    2009-01-01

    Study design Are there neuro-anatomical abnormalities associated with idiopathic scoliosis (IS)? Posterior Basicranium (PBA) reflects cerebellum growth and contains vestibular organs, two structures suspected to be involved in scoliosis. Objective The aim of this study was to compare posterior basicranium asymmetry (PBA) in Idiopathic scoliosis (IS) and normal subjects. Method: To measure the shape of PBA in 3D, we defined an intra-cranial frame of reference based on CNS and guided by embryology of the neural tube. Measurements concerned three directions of space referred to a specific intra cranial referential. Data acquisition was performed with T2 MRI (G.E. Excite 1.5T, mode Fiesta). We explored a scoliosis group of 76 women and 20 men with a mean age of 17, 2 and a control group of 26 women and 16 men, with a mean age of 27, 7. Results: IS revealed a significant asymmetry of PBA (Pr>|t|<.0001) in 3 directions of space compared to the control group. This asymmetry was more pronounced in antero-posterior...

  5. Barrier function of the posterior capsule

    International Nuclear Information System (INIS)

    The permeability of the rabbit lens and human cataractous lens posterior capsule to epinephrine and trypan blue and the absorption of ultraviolet and visible light through the posterior capsule were studied in vitro. The posterior capsule served as a barrier to large nonelectrolytes or negative electrolytes other than trypan blue, but it did not impede epinephrine, ultraviolet or visible light

  6. CT and MR Studies of Giant Dermoid Cyst Associated to Fat Dissemination at the Cortical and Cisternal Cerebral Spaces

    Directory of Open Access Journals (Sweden)

    Alessandro D'Amore

    2013-01-01

    Full Text Available This study focuses on CT and MR studies of adult patient with giant lesion of the posterior cranial fossa associated with micro- and macroaccumulations with density and signal like “fat” at the level of the cortical and cisternal cerebral spaces. This condition is compatible with previous asymptomatic ruptured dermoid cyst. Histological findings confirm the hypothesis formulated using the imaging. We also integrate elements of differential diagnosis by another giant lesion of the posterior cranial fossa.

  7. Posterior Fossa Tumor in Children

    Directory of Open Access Journals (Sweden)

    Seyed Mahmoud TABATABAEI

    2012-06-01

    Full Text Available How to Cite this Article: Tabatabaei SM, Seddighi A, Seddighi AS. Posterior Fossa Tumor in Children. Iran. J. Child. Neurol 2012;6(2: 19-24. Objective Primary brain tumors are the most common solid neoplasms of childhood, representing 20% of all pediatric tumors. The best current estimates place the incidence between 2.76 and 4.28/100,000 children per year. Compared with brain tumors in adults, a much higher percentage of pediatric brain tumors arise in the posterior fossa. Infratentorial tumors comprise as many as two thirds of all pediatric brain tumors in some large series. Tumor types that most often occur in the posterior fossa include medulloblastoma, ependymoma, cerebellar astrocytoma and brainstem glioma. Materials & Methods All pediatric cases of posterior fossa tumor that were considered for surgery from 1981 to 2011 were selected and the demographic data including age, gender and tumor characteristics along with the location and pathological diagnosis were recorded. The surgical outcomes were assessed according to pathological diagnosis. Results Our series consisted of 84 patients (52 males, 32 females. Cerebellar symptoms were the most common cause of presentation (80.9% followed by headache (73.8% and vomiting (38.1%. The most common histology was medulloblastoma (42.8% followed by cerebellar astrocytoma (28.6%, ependymoma (14.3%, brainstem glioma (7.2% and miscellaneous pathologies (e.g., dermoid,  andtuberculoma (7.2%. Conclusion The diagnosis of brain tumors in the general pediatric population remains challenging. Most symptomatic children require several visits to a physician before the correct diagnosis is made. These patients are often misdiagnosed for gastrointestinal disorders. Greater understanding of the clinical presentation of these tumors and judicious use of modern neuroimaging techniques should lead to more efficacious therapies.References 1. Mehta V, Chapman A, McNeely PD, Walling S, Howes WJ. Latency between

  8. Extraversion and fronto-posterior EEG spectral power gradient: an independent component analysis.

    Science.gov (United States)

    Knyazev, Gennady G; Bocharov, Andrey V; Pylkova, Liudmila V

    2012-02-01

    Several studies show that the fronto-posterior EEG spectral power gradient is a stable individual characteristic related to personality. Whether this characteristic is specifically related to agentic extraversion and theta band of frequencies or is associated with a broader set of personality traits and frequency bands is a matter of debate, as well as the specific cortical regions contributing to this effect. To clarify these questions, we used group independent component analysis (ICA) and source localization techniques. Agentic extraversion was associated with higher theta activity in the default mode network's (DMN) posterior hub and lower theta activity in the orbitofrontal cortex (OFC). Regression analyses showed that theta activity predicted agentic extraversion better than other frequency bands and agentic extraversion predicted posterior versus frontal activity better than other personality dimensions. These results are taken to indicate higher tonic activity in OFC and lower activity in DMN in extraverts as compared to introverts. PMID:22234364

  9. Posterior reversibile encephalopathic syndrom: case report and review of literature

    Directory of Open Access Journals (Sweden)

    Petrović Branko B.

    2003-01-01

    Full Text Available INTRODUCTION Reversible Posterior Leukoencephalopathy Syndrome was introduced into clinical practice in 1996 in order to describe unique syndrome, clinically expressed during hypertensive and uremic encephalopathy, eclampsia and during immunosuppressive therapy [1 ]. First clinical investigations showed that leucoencephalopathy is major characteristic of the syndrome, but further investigations showed no significant destruction in white cerebral tissue [2, 3,4]. In majority of cases changes are localize in posterior irrigation area of the brain and in the most severe cases anterior region is also involved. Taking into consideration all above mentioned facts, the suggested term was Posterior Reversible Encephalopathy Syndrome (PRES for the syndrome clinically expressed by neurological manifestations derived from cortical and subcortical changes localized in posterior regions of cerebral hemispheres cerebral trunk and cerebellum [5]. CASE REPORT Patient, aged 53 years, was re-hospitalized in Cardiovascular Institute "Dedinje" two months after succesfull aorto-coronary bypass performed in June 2001 due to the chest bone infection. During the treatment of the infection (according to the antibiogram in September 2001, patient in evening hours developed headache and blurred vision. The recorded blood pressure was 210/120 mmHg so antihypertensive treatment was applied (Nifedipin and Furosemid. After this therapy there was no improvement and intensive headache with fatigue and loss of vision developed. Neurological examination revealed cortical blindness and left hemiparesis. Manitol (20%, 60 ccm every 3 hours and iv. Nytroglicerin (high blood pressure. Brain CT revealed oedema of parieto-occipital regions of both hemispheres, more emphasized on the right. (Figure 1 a, b, c. There was no sign of focal ischemia even in deeper sections (Figure 1d, e, f. Following three days enormous high blood pressure values were registered. On the fourth day the

  10. Imaging of Retrochiasmal and Higher Cortical Visual Disorders.

    Science.gov (United States)

    Tantiwongkosi, Bundhit; Salamon, Noriko

    2015-08-01

    Retrochiasmal visual pathways include optic tracts, lateral geniculate nuclei, optic radiations, and striate cortex (V1). Homonymous hemianopsia and field defect variants with relatively normal visual acuity suggest that the lesions involve retrochiasmal pathways. From V1, visual input is projected to higher visual association areas that are responsible for perception of objects, faces, colors, and orientation. Visual association areas are classified into ventral and dorsal pathways. Damage to the ventral stream results in visual object agnosia, prosopagnosia, and achromatopsia. Balint syndrome, visual inattention, and pure alexia are examples of dorsal stream disorders. Posterior cortical atrophy can involve ventral and dorsal streams, often preceding dementia. PMID:26208417

  11. Ressonância magnética na mielopatia associada ao HTLV-I: Leucoencefalopatia e atrofia medular Magnetic resonance in HTLV-I associated myelopathy: leukoencephalopathy and spinal cord atrophy

    Directory of Open Access Journals (Sweden)

    Ana Claudia Ferraz

    1997-01-01

    Full Text Available Lesões na substância branca cerebral e atrofia medular têm sido descritas em pacientes com mielopatia associada ao HTLV-I (MAH. A freqüência e a importância clínica destes achados ainda não são totalmente conhecidas. Vinte e nove pacientes foram estudados por ressonância magnética (RM do crânio e da coluna. Imagens com hipersinal em T2 na substância branca, de diâmetro igual ou superior a 3 mm foram consideradas anormais. O tamanho da medula foi avaliado usando índice por nós denominado "índice medular". Os achados neurorradiológicos foram correlacionados às características clínicas da mielopatia. Lesões na substância branca cerebral ocorreram em 52% dos pacientes e atrofia medular ocorreu em 74%. Não houve correlação entre os achados neurorradiológicos e as características clínicas estudadas. Os resultados sugerem que a RM é um método útil na detecção de anormalidades cerebrais e medulares em pacientes com MAH. As lesões de substância branca não apresentaram correlação com idade ou com fatores de risco cardiovascular e podem estar associadas à infecção pelo vírus HTLV-I.Cerebral white matter lesions and spinal cord atrophy have been frequently reported in patients with HTLV-I associated myelopathy (HAM. The exact frequency and the clinical relevance of these findings still remain to be elucidated. Twenty-nine patients with HAM were studied by magnetic resonance imaging of the brain and spine. Cerebral white matter lesions equal or over 3 mm in diameter were considered abnormal. The spinal cord size was evaluated using an index we have called "spinal cord index". The radiological findings were correlated to the clinical features of the myelopathy. Cerebral white matter lesions occurred in 52% of the patients, and spinal cord atrophy in 74%. There was no significant correlation between these abnormalities and the clinical features studied. These findings suggest that the resonance imaging is a useful

  12. Tibial posterior en incontinencia urinaria

    OpenAIRE

    Pérez, Virginia

    2012-01-01

    El presente trabajo tuvo como objetivo general, indagar la eficacia y el impacto en la calidad de vida de la estimulación percutánea del nervio tibial posterior en mujeres con incontinencia urinaria. La muestra fue de 38 pacientes que habían realizado previamente el tratamiento. Luego de un periodo de tratamiento, respondieron un cuestionario de calidad de vida que contemplo diferentes áreas. Se utilizó el Cuestionario de Salud King como modelo, debido a que este se encuentra dentro del proto...

  13. Cortico-cortical communication dynamics

    Directory of Open Access Journals (Sweden)

    Per E Roland

    2014-05-01

    Full Text Available IIn principle, cortico-cortical communication dynamics is simple: neurons in one cortical area communicate by sending action potentials that release glutamate and excite their target neurons in other cortical areas. In practice, knowledge about cortico-cortical communication dynamics is minute. One reason is that no current technique can capture the fast spatio-temporal cortico-cortical evolution of action potential transmission and membrane conductances with sufficient spatial resolution. A combination of optogenetics and monosynaptic tracing with virus can reveal the spatio-temporal cortico-cortical dynamics of specific neurons and their targets, but does not reveal how the dynamics evolves under natural conditions. Spontaneous ongoing action potentials also spread across cortical areas and are difficult to separate from structured evoked and intrinsic brain activity such as thinking. At a certain state of evolution, the dynamics may engage larger populations of neurons to drive the brain to decisions, percepts and behaviors. For example, successfully evolving dynamics to sensory transients can appear at the mesoscopic scale revealing how the transient is perceived. As a consequence of these methodological and conceptual difficulties, studies in this field comprise a wide range of computational models, large-scale measurements (e.g., by MEG, EEG, and a combination of invasive measurements in animal experiments. Further obstacles and challenges of studying cortico-cortical communication dynamics are outlined in this critical review.

  14. Modeling cortical circuits.

    Energy Technology Data Exchange (ETDEWEB)

    Rohrer, Brandon Robinson; Rothganger, Fredrick H.; Verzi, Stephen J.; Xavier, Patrick Gordon

    2010-09-01

    The neocortex is perhaps the highest region of the human brain, where audio and visual perception takes place along with many important cognitive functions. An important research goal is to describe the mechanisms implemented by the neocortex. There is an apparent regularity in the structure of the neocortex [Brodmann 1909, Mountcastle 1957] which may help simplify this task. The work reported here addresses the problem of how to describe the putative repeated units ('cortical circuits') in a manner that is easily understood and manipulated, with the long-term goal of developing a mathematical and algorithmic description of their function. The approach is to reduce each algorithm to an enhanced perceptron-like structure and describe its computation using difference equations. We organize this algorithmic processing into larger structures based on physiological observations, and implement key modeling concepts in software which runs on parallel computing hardware.

  15. Longevity of Posterior Composite Restorations

    Science.gov (United States)

    Opdam, N.J.M.; van de Sande, F.H.; Bronkhorst, E.; Cenci, M.S.; Bottenberg, P.; Pallesen, U.; Gaengler, P.; Lindberg, A.; Huysmans, M.C.D.N.J.M.; van Dijken, J.W.

    2014-01-01

    The aim of this meta-analysis, based on individual participant data from several studies, was to investigate the influence of patient-, materials-, and tooth-related variables on the survival of posterior resin composite restorations. Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we conducted a search resulting in 12 longitudinal studies of direct posterior resin composite restorations with at least 5 years’ follow-up. Original datasets were still available, including placement/failure/censoring of restorations, restored surfaces, materials used, reasons for clinical failure, and caries-risk status. A database including all restorations was constructed, and a multivariate Cox regression method was used to analyze variables of interest [patient (age; gender; caries-risk status), jaw (upper; lower), number of restored surfaces, resin composite and adhesive materials, and use of glass-ionomer cement as base/liner (present or absent)]. The hazard ratios with respective 95% confidence intervals were determined, and annual failure rates were calculated for subgroups. Of all restorations, 2,816 (2,585 Class II and 231 Class I) were included in the analysis, of which 569 failed during the observation period. Main reasons for failure were caries and fracture. The regression analyses showed a significantly higher risk of failure for restorations in high-caries-risk individuals and those with a higher number of restored surfaces. PMID:25048250

  16. The Cortical Signature of Central Poststroke Pain: Gray Matter Decreases in Somatosensory, Insular, and Prefrontal Cortices.

    Science.gov (United States)

    Krause, T; Asseyer, S; Taskin, B; Flöel, A; Witte, A V; Mueller, K; Fiebach, J B; Villringer, K; Villringer, A; Jungehulsing, G J

    2016-01-01

    It has been proposed that cortical structural plasticity plays a crucial role in the emergence and maintenance of chronic pain. Various distinct pain syndromes have accordingly been linked to specific patterns of decreases in regional gray matter volume (GMV). However, it is not known whether central poststroke pain (CPSP) is also associated with cortical structural plasticity. To determine this, we employed T1-weighted magnetic resonance imaging at 3 T and voxel-based morphometry in 45 patients suffering from chronic subcortical sensory stroke with (n = 23) and without CPSP (n = 22), and healthy matched controls (n = 31). CPSP patients showed decreases in GMV in comparison to healthy controls, involving secondary somatosensory cortex (S2), anterior as well as posterior insular cortex, ventrolateral prefrontal and orbitofrontal cortex, temporal cortex, and nucleus accumbens. Comparing CPSP patients to nonpain patients revealed a similar but more restricted pattern of atrophy comprising S2, ventrolateral prefrontal and temporal cortex. Additionally, GMV in the ventromedial prefrontal cortex negatively correlated to pain intensity ratings. This shows for the first time that CPSP is accompanied by a unique pattern of widespread structural plasticity, which involves the sensory-discriminative areas of insular/somatosensory cortex, but also expands into prefrontal cortex and ventral striatum, where emotional aspects of pain are processed. PMID:25129889

  17. Posterior reversible encephalopathy syndrome in leukemic children: a sensitive issue.

    Science.gov (United States)

    Kridis, Wala Ben; Mdhaffer, Moez; Hentati, Yosr; Kammoun, Fatma; Milad, Abir; Haddar, Sondes; Mahfoudh, Khaireddine Ben; Triki, Chahinez; Elloumi, Moez

    2015-01-01

    Posterior reversible encephalopathy syndrome (PRES) is an acute central nervous system disorder characterized by reversible brain vasogenic edema. We report here a new case of a nine-year-old boy with B-cell acute lymphoblastic leukemia (B-ALL) who developed PRES secondary to induction chemotherapy including dexamethasone (dexamethasone®), vincristine (oncovin(®)), daunorubicin (adriblastine(®)) and intrathecal injection. Cerebral magnetic resonance imaging (MRI) showed high signal intensity on T2 at cortical and sub cortical region of parieto-frontal and parieto-occipital lobes. The patient was put under sodium valproate (depakine(®)) and we decided to continue dexamethasone (dexamethasone(®)) and daunorubicin (adriblastine(®)) injection. The MRI, after four weeks, was normal. So, we resumed vincristine (oncovin(®)) and we started L-asparaginase injections. Then, the outcome was favorable. The treatment of PRES is based on the withdrawal of the triggering factor to avoid the risk of irreversible lesions. But, due to the severity of leukemia the discontinuation of chemotherapy is difficult because of the risk of disease progression. PMID:24919742

  18. Paradigm Shift in the Management of the Atrophic Posterior Maxilla

    Directory of Open Access Journals (Sweden)

    Rabah Nedir

    2014-01-01

    Full Text Available When the posterior maxilla is atrophic, the reference standard of care would be to perform sinus augmentation with an autologous bone graft through the lateral approach and delayed implant placement. However, placement of short implants with the osteotome sinus floor elevation technique and without graft can be proposed for an efficient treatment of clinical cases with a maxillary residual bone height of 4 to 8 mm. The use of grafting material is recommended only when the residual bone height is ≤4 mm. Indications of the lateral sinus floor elevation are limited to cases with a residual bone height ≤ 2 mm and fused corticals, uncompleted healing of the edentulous site, and absence of flat cortical bone crest or when the patient wishes to wear a removable prosthesis during the healing period. The presented case report illustrates osteotome sinus floor elevation with and without grafting and simultaneous implant placement in extreme conditions: atrophic maxilla, short implant placement, reduced healing time, and single crown rehabilitation. After 6 years, all placed implants were functional with an endosinus bone gain.

  19. Sex, age, and cognitive correlates of asymmetries in thickness of the cortical mantle across the life span

    DEFF Research Database (Denmark)

    Plessen, Kerstin J; Hugdahl, Kenneth; Bansal, Ravi;

    2014-01-01

    We assessed the correlations of age, sex, and cognitive performance with measures of asymmetry in cortical thickness on high-resolution MRIs in 215 healthy human children and adults, 7-59 years of age. A left > right asymmetry in thickness of the cortical mantle was present throughout the entire...... the entire inferior surface of the brain. An exaggerated left > right asymmetry was detected in females in anterior brain regions, and an exaggerated right > left asymmetry was detected in males in the orbitofrontal, inferior parietal, and inferior occipital cortices. Weaker moderating effects of sex...... were scattered along the mesial surface of the brain. Age significantly moderated asymmetry measures in the inferior sensorimotor, inferior parietal, posterior temporal, and inferior occipital cortices. The age × asymmetry interaction derived from a steeper decline in cortical thickness with age in the...

  20. Stress fracture in posterior aspect of the tibia

    International Nuclear Information System (INIS)

    To determine correlation between stress fracture of the posterior tibia and flexor digitorum longus muscle injury caused by athletic or sporting activity during adolescence. Eleven cases diagnosed as stress fracture after X-ray and MR imaging of the lower leg were reviewed. With regard to each fracture, the following features were noted : age, sex, and athletic or sporting activity of the patient, and site. Using MR imaging techniques, axial and sagittal T1 and T2 weighted imaged were obtained in all cases and T1-Gd DTPA images in seven. The activities undertaken were running (n=3), football (n=2), ballet (n=2), taekwando (n=1), badminton (n=1), field hockey (n=1), and basketball (n=1). MR images revealed localized cortical thickness (n=11), linear intramedullary callus showing a low signal on T1 and T2 weighted images (n=9), marrow hyperemia (n=7), and flexor digitorum longus muscle injury showing a high signal on T1-Gd DTPA and T2 weighted image (n=7). Stress fracture of the posterior tibia might be induced by flexor digitorum longus muscle activity induced by athletic or sporting activities during adolescence

  1. Stress fracture in posterior aspect of the tibia

    Energy Technology Data Exchange (ETDEWEB)

    Moon, Tae Yong; Jung, Hyun Woo; Park, Chung Hun [Pusan National Univ. College of Medicine, Pusan (Korea, Republic of); Chun, Kyung Ah [Catholic Univ Hospital, Pusan (Korea, Republic of); Koo, Bong Sig [Donga Univ. Hospital, Pusan (Korea, Republic of); Lee, Sang Yong [Chunbuk Natinoal Univ. Hospital, Chunju (Korea, Republic of)

    1999-01-01

    To determine correlation between stress fracture of the posterior tibia and flexor digitorum longus muscle injury caused by athletic or sporting activity during adolescence. Eleven cases diagnosed as stress fracture after X-ray and MR imaging of the lower leg were reviewed. With regard to each fracture, the following features were noted : age, sex, and athletic or sporting activity of the patient, and site. Using MR imaging techniques, axial and sagittal T1 and T2 weighted imaged were obtained in all cases and T1-Gd DTPA images in seven. The activities undertaken were running (n=3), football (n=2), ballet (n=2), taekwando (n=1), badminton (n=1), field hockey (n=1), and basketball (n=1). MR images revealed localized cortical thickness (n=11), linear intramedullary callus showing a low signal on T1 and T2 weighted images (n=9), marrow hyperemia (n=7), and flexor digitorum longus muscle injury showing a high signal on T1-Gd DTPA and T2 weighted image (n=7). Stress fracture of the posterior tibia might be induced by flexor digitorum longus muscle activity induced by athletic or sporting activities during adolescence.

  2. Cortical signature of patients with HBV-related cirrhosis without overt hepatic encephalopathy: a morphometric analysis.

    Science.gov (United States)

    Wu, Xiu; Lv, Xiao-Fei; Zhang, Yu-Ling; Wu, Hua-Wang; Cai, Pei-Qiang; Qiu, Ying-Wei; Zhang, Xue-Lin; Jiang, Gui-Hua

    2015-01-01

    Previous studies have shown that patients with hepatitis B virus-related cirrhosis (HBV-RC) without overt hepatic encephalopathy (OHE) are associated with a varying degree of cognitive dysfunction. Several resting-state functional magnetic resonance imaging (fMRI) studies have been conducted to explore the neural correlates of such cognitive deficits, whereas little effort has been made to investigate the cortical integrity in cirrhotic patients without OHE. Here, using cortical thickness, surface area and local gyrification index (lGI), this study performed a comprehensive analysis on the cortical morphometry of patients with HBV-RC without OHE (HBV-RC-NOHE) vs. matched healthy controls. Compared with healthy controls, we found significantly increased cortical thickness in the bilateral lingual and parahippocampal gyrus, right posterior cingulate cortex, precuneus, peri-calcarine sulcus and fusiform gyrus in patient with HBV-RC-NOHE, which may closely relate to be the low-grade brain edema. Cortical gyrification analysis showed significantly increased lGI in the left superior and inferior parietal cortex as well as lateral occipital cortex, which was speculated to be associated with disruptions in white matter connectivity and sub-optimal intra-cortical organization. In addition, the mean cortical thickness/lGI of the regions with structural abnormalities was shown to be negatively correlated with psychometric hepatic encephalopathy score (PHES) of the patients with HBV-RC-NOHE. These morphological changes may serve as potential markers for the preclinical diagnosis and progression of HBV-RC-NOHE. PMID:26106307

  3. Heterogeneous and nonlinear development of human posterior parietal cortex function.

    Science.gov (United States)

    Chang, Ting-Ting; Metcalfe, Arron W S; Padmanabhan, Aarthi; Chen, Tianwen; Menon, Vinod

    2016-02-01

    Human cognitive problem solving skills undergo complex experience-dependent changes from childhood to adulthood, yet most neurodevelopmental research has focused on linear changes with age. Here we challenge this limited view, and investigate spatially heterogeneous and nonlinear neurodevelopmental profiles between childhood, adolescence, and young adulthood, focusing on three cytoarchitectonically distinct posterior parietal cortex (PPC) regions implicated in numerical problem solving: intraparietal sulcus (IPS), angular gyrus (AG), and supramarginal gyrus (SMG). Adolescents demonstrated better behavioral performance relative to children, but their performance was equivalent to that of adults. However, all three groups differed significantly in their profile of activation and connectivity across the PPC subdivisions. Activation in bilateral ventral IPS subdivision IPS-hIP1, along with adjoining anterior AG subdivision, AG-PGa, and the posterior SMG subdivision, SMG-PFm, increased linearly with age, whereas the posterior AG subdivision, AG-PGp, was equally deactivated in all three groups. In contrast, the left anterior SMG subdivision, SMG-PF, showed an inverted U-shaped profile across age groups such that adolescents exhibited greater activation than both children and young adults. Critically, greater SMG-PF activation was correlated with task performance only in adolescents. Furthermore, adolescents showed greater task-related functional connectivity of the SMG-PF with ventro-temporal, anterior temporal and prefrontal cortices, relative to both children and adults. These results suggest that nonlinear up-regulation of SMG-PF and its interconnected functional circuits facilitate adult-level performance in adolescents. Our study provides novel insights into heterogeneous age-related maturation of the PPC underlying cognitive skill acquisition, and further demonstrates how anatomically precise analysis of both linear and nonlinear neurofunctional changes with age is

  4. Enfermedad de Creutzfeldt-Jakob por RMI: alteración cortical como signo temprano de la enfermedad Creutzfeldt-Jakob disease by MRI: Cortical alteration as early sign disease

    Directory of Open Access Journals (Sweden)

    María Fernanda Markarian

    2008-12-01

    Full Text Available Se estudió por RMI un paciente de 59 años con diagnóstico probable de Enfermedad de Creutzfeldt-Jakob desde el inicio de sus síntomas. El paciente comienza con un cuadro de leve deterioro cognitivo. En una primera resonancia en secuencias FLAIR se visualiza hiperintensidad cortical a predomino de hemisferio izquierdo, no observándose en FSE T 2. Se hace más significativa en nueva resonancia en FLAIR y Difusión, con aparición de hiperintensidad en cabeza de ambos caudados y rápido deterioro cognitivo, alteraciones visuales, aparición de signos piramidales y extrapiramidales, convulsiones y mioclonias y mutismo. Con la acentuación de las alteraciones corticales -y en los ganglios de la base en una tercera resonancia-, el paciente trasforma su ECG de ritmo lento a un ritmo de punta-onda bifásico y trifásico. A 3 meses de la primera resonancia, nuevas imágenes muestran atrofia e importante hiperintensidad cortical y en ganglios de la base. En conclusión, las secuencias FLAIR y Difusión serían más sensibles que las secuencias T2 en la detección del aumento de intensidad de señal en la corteza cerebral, siendo un indicio diagnóstico temprano de la enfermedad de Creutzfeld-Jakob.A 59-year-old man with probable Creutzfeldt-Jakob disease was studied from early symptoms. The patients manifested mild cognitive impairment. The first magnetic resonance showed hiperintense signal cortical abnormalities in FLAIR sequence predominantly in left hemisphere, FSE T2 no showed abnormalities. In other resonance those abnormities were more significative and appeared head of the caudate nucleus abnormalities in FLAIR and Diffusion-weighted, the patients began with rapidly progressing impairment, visual disturbance, pyramidal and extrapyramidal signs, seizures, myoclonus and mutism. The third resonance revealed cortical and basal ganglia high signal intensity abnormalities and the patient transformed slowing EEG to biphasic and triphasic sharp

  5. CORTICAL CLEANUP WITHOUT SIDE PORT IN SMALL INCISION CATARACT SURGERY

    Directory of Open Access Journals (Sweden)

    Udaya Kumar

    2015-11-01

    Full Text Available The aim of study was to achieve complete cortical cleanup and avoid problems related with sideport during Small Incision Cataract Surgery (SICS so as to have a good visual out come with minimal recovery period, and a better quality of life. After nucleus delivery, cortical cleanup is an important step in any cataract surgical procedure. Cortex especially subincisional area (11 to 1 o’clock is difficult to manage intraoperatively. Bimanual irrigation aspiration through two side ports, aspiration by J cannula, iris massage manoeuver, ice cream scoop manoeuver are various techniques of cortical matter aspiration. We acquired the technique of aspiration of subincisional cortex without using side port in all cases by paying attention on type of cataract, status of pupil, use of Adrenalin mixed BSS intraoperatively, Tunnel construction, Capsulorhexis size and capsular rim size at 12 o’clock. MATERIAL AND METHODS In this retrospective study of 1 year from 2013 to 2014, 60 patients (60 eyes aged 40 years or older attending the General Ophthalmic Department were included in the study group with another group of 60 patients (60 eyes as controls. The study was on age related cataracts which are basically. 1 Cortical cataract 2 Nuclear cataract 3 Subcapsular cataract. Proper assessment of cortical cataract based on its maturity such as a Immature b Mature c Hyper mature and d Morgagnian cataract, nucleus for its opalescence and color, size of posterior subcapsular opacity and pupillary status (Dilating well or not with mydriatics were taken into consideration. Eyes with pseudoexfoliation having poor pupillary dilation were also included. Eyes with congenital anomalies, congenital cataract, gross corneal and retinal pathologies, and glaucoma were excluded. RESULTS Among 60 study eyes in the study group 35 presented with cortical, 20 with nuclear cataract and 5 with posterior subcapsular cataracts. In 58(96.6% cases, sideport was not required; 3(5% eyes

  6. Aggressive posterior retinopathy of prematurity classification

    OpenAIRE

    A.V. Tereshchenko,; Yu. A. Belyy; M. S. Tereshchenkova; I. G. Trifanenkova

    2013-01-01

    ABSTRACT Based on dynamic monitoring of 133 premature infants (266 eyes) with aggressive posterior retinopathy of prematurity (ROP), digital retinoscopy and computer morphometry the disease clinical and morphometric features were revealed and systematized, and their consecutive replacement was fixed. As a result the separate classification of aggressive posterior disease was worked up. In aggressive posterior ROP course the next consecutive stages were marked out: subclinical, early ...

  7. Minimally invasive posterior hamstring harvest.

    Science.gov (United States)

    Wilson, Trent J; Lubowitz, James H

    2013-01-01

    Autogenous hamstring harvesting for knee ligament reconstruction is a well-established standard. Minimally invasive posterior hamstring harvest is a simple, efficient, reproducible technique for harvest of the semitendinosus or gracilis tendon or both medial hamstring tendons. A 2- to 3-cm longitudinal incision from the popliteal crease proximally, in line with the semitendinosus tendon, is sufficient. The deep fascia is bluntly penetrated, and the tendon or tendons are identified. Adhesions are dissected. Then, an open tendon stripper is used to release the tendon or tendons proximally; a closed, sharp tendon stripper is used to release the tendon or tendons from the pes. Layered, absorbable skin closure is performed, and the skin is covered with a skin sealant, bolster dressing, and plastic adhesive bandage for 2 weeks. PMID:24266003

  8. Lesion Analysis of Cortical Regions Associated with the Comprehension of Nonreversible and Reversible Yes/No Questions

    Science.gov (United States)

    Race, David S.; Ochfeld, Elisa; Leigh, Richard; Hillis, Argye E.

    2012-01-01

    We investigated the association between yes/no sentence comprehension and dysfunction in anterior and posterior left-hemisphere cortical regions in acute stroke patients. More specifically, we manipulated whether questions were Nonreversible (e.g., Are limes sour?) or Reversible (e.g., Is a horse larger than a dog?) to investigate the regions…

  9. Cortical thickness and surface area in neonates at high risk for schizophrenia.

    Science.gov (United States)

    Li, Gang; Wang, Li; Shi, Feng; Lyall, Amanda E; Ahn, Mihye; Peng, Ziwen; Zhu, Hongtu; Lin, Weili; Gilmore, John H; Shen, Dinggang

    2016-01-01

    Schizophrenia is a neurodevelopmental disorder associated with subtle abnormal cortical thickness and cortical surface area. However, it is unclear whether these abnormalities exist in neonates associated with genetic risk for schizophrenia. To this end, this preliminary study was conducted to identify possible abnormalities of cortical thickness and surface area in the high-genetic-risk neonates. Structural magnetic resonance images were acquired from offspring of mothers (N = 21) who had schizophrenia (N = 12) or schizoaffective disorder (N = 9), and also matched healthy neonates of mothers who were free of psychiatric illness (N = 26). Neonatal cortical surfaces were reconstructed and parcellated as regions of interest (ROIs), and cortical thickness for each vertex was computed as the shortest distance between the inner and outer surfaces. Comparisons were made for the average cortical thickness and total surface area in each of 68 cortical ROIs. After false discovery rate (FDR) correction, it was found that the female high-genetic-risk neonates had significantly thinner cortical thickness in the right lateral occipital cortex than the female control neonates. Before FDR correction, the high-genetic-risk neonates had significantly thinner cortex in the left transverse temporal gyrus, left banks of superior temporal sulcus, left lingual gyrus, right paracentral cortex, right posterior cingulate cortex, right temporal pole, and right lateral occipital cortex, compared with the control neonates. Before FDR correction, in comparison with control neonates, male high-risk neonates had significantly thicker cortex in the left frontal pole, left cuneus cortex, and left lateral occipital cortex; while female high-risk neonates had significantly thinner cortex in the bilateral paracentral, bilateral lateral occipital, left transverse temporal, left pars opercularis, right cuneus, and right posterior cingulate cortices. The high-risk neonates also had significantly

  10. Extraversion and anterior vs. posterior DMN activity during self-referential thoughts.

    Science.gov (United States)

    Knyazev, Gennady G

    2012-01-01

    Recent studies show that fronto-posterior electroencephalogram (EEG) spectral power distribution is associated with personality. Specifically, extraversion is associated with an increase of spectral power in posterior cortical regions that overlap with the posterior default mode network (DMN) hub and a decrease of spectral power in anterior regions that overlap with the anterior DMN hub. Although there is evidence that dopaminergic neurotransmission may be involved, psychological processes that underlie these associations remain unclear. I hypothesize that these processes may have something to do with spontaneous self-referential thoughts. Specifically, I hypothesize that in extraverts self-referential thoughts may be associated with an increase of spectral power in the posterior DMN hub, whereas in introverts they may be associated with an increase of spectral power in the anterior DMN hub. After spontaneous EEG registration, participants were asked to fill in a questionnaire describing their thoughts during the registration. An item describing self-referential positive expectations (SRPE) was used to measure individual differences in the intensity of these processes. Source localization and independent component analyses were applied to EEG data to reveal oscillatory activity associated with the anterior and the posterior DMN hubs. Hierarchical regression analysis showed a significant interaction between extraversion scores and anterior vs. posterior DMN alpha activity in predicting individual differences in SRPE scores. In extraverts, high SRPE scores were associated with an increase of alpha power in the posterior DMN hub, whereas in introverts they were associated with an increase of alpha power in the anterior DMN hub. Results are discussed in terms of differential involvement of the two DMN hubs in self-related reward processes in extraverts and introverts. PMID:23419982

  11. Extraversion and anterior vs. posterior DMN activity during self-referential thoughts.

    Directory of Open Access Journals (Sweden)

    Gennady G. Knyazev

    2013-01-01

    Full Text Available Recent studies show that fronto-posterior electroencephalogram (EEG spectral power distribution is associated with personality. Specifically, extraversion is associated with an increase of spectral power in posterior cortical regions that overlap with the posterior default mode network (DMN hub and a decrease of spectral power in anterior regions that overlap with the anterior DMN hub. Although there is evidence that dopaminergic neurotransmission may be involved, psychological processes that underlie these associations remain unclear. We hypothesize that these processes may have something to do with spontaneous self-referential thoughts. Specifically, we hypothesize that in extraverts self-referential thoughts may be associated with an increase of spectral power in the posterior DMN hub, whereas in introverts they may be associated with an increase of spectral power in the anterior DMN hub. After spontaneous EEG registration, participants were asked to fill in a questionnaire describing their thoughts during the registration. An item describing self-referential positive expectations (SRPE was used to measure individual differences in the intensity of these processes. Source localization and independent component analyses were applied to EEG data to reveal oscillatory activity associated with the anterior and the posterior DMN hubs. Hierarchical regression analysis showed a significant interaction between extraversion scores and anterior vs. posterior DMN alpha activity in predicting individual differences in SRPE scores. In extraverts, high SRPE scores were associated with an increase of alpha power in the posterior DMN hub, whereas in introverts they were associated with an increase of alpha power in the anterior DMN hub. Results are discussed in terms of differential involvement of the two DMN hubs in self-related reward processes in extraverts and introverts.

  12. Focal cortical dysplasia – review

    International Nuclear Information System (INIS)

    Focal cortical dysplasia is a malformation of cortical development, which is the most common cause of medically refractory epilepsy in the pediatric population and the second/third most common etiology of medically intractable seizures in adults. Both genetic and acquired factors are involved in the pathogenesis of cortical dysplasia. Numerous classifications of the complex structural abnormalities of focal cortical dysplasia have been proposed – from Taylor et al. in 1971 to the last modification of Palmini classification made by Blumcke in 2011. In general, three types of cortical dysplasia are recognized. Type I focal cortical dysplasia with mild symptomatic expression and late onset, is more often seen in adults, with changes present in the temporal lobe. Clinical symptoms are more severe in type II of cortical dysplasia usually seen in children. In this type, more extensive changes occur outside the temporal lobe with predilection for the frontal lobes. New type III is one of the above dysplasias with associated another principal lesion as hippocampal sclerosis, tumor, vascular malformation or acquired pathology during early life. Brain MRI imaging shows abnormalities in the majority of type II dysplasias and in only some of type I cortical dysplasias. The most common findings on MRI imaging include: focal cortical thickening or thinning, areas of focal brain atrophy, blurring of the gray-white junction, increased signal on T2- and FLAIR-weighted images in the gray and subcortical white matter often tapering toward the ventricle. On the basis of the MRI findings, it is possible to differentiate between type I and type II cortical dysplasia. A complete resection of the epileptogenic zone is required for seizure-free life. MRI imaging is very helpful to identify those patients who are likely to benefit from surgical treatment in a group of patients with drug-resistant epilepsy. However, in type I cortical dysplasia, MR imaging is often normal, and also in both

  13. Comparison of the Combined Anterior-Posterior Approach versus Posterior-Only Approach in Scoliosis Treatment

    OpenAIRE

    Pourfeizi, Hossein Hojjat; Sales, Jafar Ganjpour; Tabrizi, Ali; Borran, Ghanbar; Alavi, Sahar

    2014-01-01

    Study Design This is descriptive analytical study. Purpose The present study aims at comparing treatment results found between the two groups comprising of patients who underwent posterior spinal fusion using thoracic pedicle screws and the ones who underwent combined anterior-posterior method, respectively. Overview of Literature There was controversy about surgical techniques including anterior, posterior, or a combined anterior-posterior approaches are applied to treat non-congenital scoli...

  14. Dynamical models of cortical circuits.

    OpenAIRE

    Wolf, Fred; Engelken, Rainer; Puelma-Touzel, Maximilian; Weidinger, Juan Daniel Flórez; Neef, Andreas

    2014-01-01

    Cortical neurons operate within recurrent neuronal circuits. Dissecting their operation is key to understanding information processing in the cortex and requires transparent and adequate dynamical models of circuit function. Convergent evidence from experimental and theoretical studies indicates that strong feedback inhibition shapes the operating regime of cortical circuits. For circuits operating in inhibition-dominated regimes, mathematical and computational studies over the past several y...

  15. Antero-posterior EEG spectral power gradient as a correlate of extraversion and behavioral inhibition.

    Science.gov (United States)

    Knyazev, Gennady G

    2010-01-01

    Several studies have shown that individual-specific patterns of cortical spectral power distribution are relatively stable across time and experimental conditions. The antero-posterior EEG spectral power gradient (APSPG) emerged as the most prominent feature associated with important personality characteristics. In this study this phenomenon is further investigated in relation to its stability and association with different personality traits. It has been shown that APSPG is generally more pronounced during resting baseline than during inter-trial interval and post-stimulus period. Its association with personality variables is similar for different frequency bands and is mostly preserved during different experimental conditions. Relatively higher oscillatory activity in frontal than in posterior cortical sites is more frequently observed in subjects with higher behavioral inhibition (BIS) and lower Sociability. Source localization analysis showed that both high BIS/low Sociability and high APSPG are associated with higher oscillatory activity in medial cortices associated with emotion processing (mostly the cingulate gyrus). This association could be tentatively explained by higher vigilance and emotional tension in introverted and behaviorally inhibited subjects. PMID:21673979

  16. Pseudoaneurysm of the Posterior Tibial Artery After Posterior Tibial Tendon Transfer.

    Science.gov (United States)

    Elabdi, Monsef; Roukhsi, Redouane; Tijani, Youssef; Chtata, Hassan; Jaafar, Abdeloihab

    2016-01-01

    Pseudoaneurysm of the posterior tibial artery is an uncommon condition that, left untreated, can lead to hemorrhage, thrombosis, or emboli. We present the case of a 54-year-old male who developed pseudoaneurysm of the posterior tibial artery 4 months after undergoing tibialis posterior tendon transfer for management of peroneal nerve palsy, which had developed as a complication of hip arthroplasty. PMID:26972754

  17. Posterior Cervical Foraminotomy: Indications, Technique, and Outcomes.

    Science.gov (United States)

    Dodwad, Shah-Jahan M; Dodwad, Shah-Nawaz M; Prasarn, Mark L; Savage, Jason W; Patel, Alpesh A; Hsu, Wellington K

    2016-06-01

    Cervical radiculopathy presents with upper extremity pain, decreased sensation, and decreased strength caused by irritation of specific nerve root(s). After failure of conservative management, surgical options include anterior cervical decompression and fusion, disk arthroplasty, and posterior cervical foraminotomy. In this review, we discuss indications, techniques, and outcomes of posterior cervical laminoforaminotomy. PMID:27187617

  18. DIAGNOSIS DAN PENATALAKSANAAN KATUP URETRA POSTERIOR

    OpenAIRE

    Putu Primeriana Nugiaswari; Gede Wirya Kusuma Duarsa; Sri Maliawan

    2012-01-01

    Katup uretra posterior merupakan penyebab utama kesakitan, kematian, dan kerusakanginjal berkelanjutan pada anak-anak. Kelainan ini berupa lipatan mukosa abnormalkongenital pada uretra pars prostatika yang menyerupai membran tipis yangmenghambat drainase kandung kemih. Katup uretra posterior mayoritas didiagnosis saatprenatal melalui penggunaan ultrasonografi maternal. Tingkat keparahan dan derajatobstruksi yang disebabkan oleh kelainan ini tergantung pada konfigurasi dari membranobstruktif d...

  19. Cervical disc hernia operations through posterior laminoforaminotomy

    OpenAIRE

    Coskun Yolas; Nuriye Guzin Ozdemir; Hilmi Onder Okay; Ayhan Kanat; Mehmet Senol; Ibrahim Burak Atci; Hakan Yilmaz; Mustafa Kemal Coban; Mehmet Onur Yuksel; Umit Kahraman

    2016-01-01

    Objective: The most common used technique for posterolateral cervical disc herniations is anterior approach. However, posterior cervical laminotoforaminomy can provide excellent results in appropriately selected patients with foraminal stenosis in either soft disc prolapse or cervical spondylosis. The purpose of this study was to present the clinical outcomes following posterior laminoforaminotomy in patients with radiculopathy. Materials and Methods: We retrospectively evaluated 35 patients ...

  20. Analysis of anisotropic viscoelastoplastic properties of cortical bone tissues.

    Science.gov (United States)

    Abdel-Wahab, Adel A; Alam, Khurshid; Silberschmidt, Vadim V

    2011-07-01

    Bone fractures affect the health of many people and have a significant social and economic effect. Often, bones fracture due to impacts, sudden falls or trauma. In order to numerically model the fracture of a cortical bone tissue caused by an impact it is important to know parameters characterising its viscoelastoplastic behaviour. These parameters should be measured for various orientations in a bone tissue to assess bone's anisotropy linked to its microstructure. So, the first part of this study was focused on quantification of elastic-plastic behaviour of cortical bone using specimens cut along different directions with regard to the bone axis-longitudinal (axial) and transverse. Due to pronounced non-linearity of the elastic-plastic behaviour of the tissue, cyclic loading-unloading uniaxial tension tests were performed to obtain the magnitudes of elastic moduli not only from the initial loading part of the cycle but also from its unloading part. Additional tests were performed with different deformation rates to study the bone's strain-rate sensitivity. The second part of this study covered creep and relaxation properties of cortical bone for two directions and four different anatomical positions-anterior, posterior, medial and lateral-to study the variability of bone's properties. Since viscoelastoplasticity of cortical bone affects its damping properties due to energy dissipation, the Dynamic Mechanical Analysis (DMA) technique was used in the last part of our study to obtain magnitudes of storage and loss moduli for various frequencies. Based on analysis of elastic-plastic behaviour of the bovine cortical bone tissue, it was found that magnitudes of the longitudinal Young's modulus for four cortical positions were in the range of 15-24 GPa, while the transversal modulus was lower--between 10 and 15 GPa. Axial strength for various anatomical positions was also higher than transversal strength with significant differences in magnitudes for those positions

  1. Hiperostosis cortical infantil

    Directory of Open Access Journals (Sweden)

    Salvador Javier Santos Medina

    2015-04-01

    Full Text Available La enfermedad de Caffey, o hiperostosis cortical infantil, es una rara enfermedad ósea autolimitada, que aparece de preferencia en lactantes con signos inespecíficos sistémicos; el más relevante es la reacción subperióstica e hiperostosis en varios huesos del cuerpo, con predilección en el 75-80 % de los casos por la mandíbula. Su pronóstico es bueno, la mayoría no deja secuelas. El propósito del presente trabajo es describir las características clínicas, presentes en un lactante de cinco meses de edad, atendido en el Hospital Pediátrico Provincial “Mártires de Las Tunas” con este diagnóstico, quien ingresó en el servicio de miscelánea B por una celulitis facial. Presentaba aumento de volumen en la región geniana izquierda, febrícola e inapetencia. Se impuso tratamiento con cefazolina y se egresó a los siete días. Acudió nuevamente con tumefacción blanda y difusa de ambas hemicaras, irritabilidad y fiebre. Se interconsultó con cirugía maxilofacial, se indicaron estudios sanguíneos y radiológicos. Se diagnosticó como enfermedad de Caffey, basado en la edad del niño, tumefacción facial sin signos inflamatorios agudos e hiperostosis en ambas corticales mandibulares a la radiografía AP mandíbula; unido a anemia ligera, leucocitosis y eritrosedimentación acelerada. El paciente se trató sintomáticamente y con antinflamatorios no esteroideos. Esta rara entidad se debe tener presente en casos de niños y lactantes con irritabilidad y fiebre inespecífica

  2. Anatomic variations of anterior cerebral artery cortical branches.

    Science.gov (United States)

    Stefani, M A; Schneider, F L; Marrone, A C; Severino, A G; Jackowski, A P; Wallace, M C

    2000-01-01

    The anterior cerebral artery (ACA) is a major vessel responsible for the blood supply to the interhemispheric region. The ACA segment after the anterior communicating artery (AComA) origin is called the distal ACA and has central and cortical branches. The cortical branches are distributed in the different regions of the orbital and medial part of the brain. The objects of this study are the anatomical variations found in the distal ACA. In 76 hemispheres the ACA distal branches were injected with latex and dissected under microscope magnification. Vessel diameters and distances between vessel origins and anterior communicating artery were recorded and analyzed. Microsurgical dissection was carried out to demonstrate anatomic variations of these vessels. Average diameter of ACA at origin was 2.61 +/- 0.34 mm and average diameter of cortical branches diameter ranged from 0.79 +/- 0.27 mm to 1.84 +/- 0.3 mm. Distances between vessel origin and AComA ranged from 7.68 +/- 3.91 mm (orbitofrontal) to 112.6 +/- 11.63 mm (inferior internal parietal). This study found anatomical variations: a single (azygos) ACA was present in one case and three in three cases. Crossing branches of the distal ACA to the contralateral hemisphere were present in 26% of the cases. In some cases a single ACA may supply the posterior hemispheric region through crossing branches. This calls attention to potential bilateral brain infarcts due to a single unilateral ACA occlusion. PMID:10873213

  3. Somatosensory evoked potentials following stimulation of the lower limb in cortical reflex myoclonus.

    OpenAIRE

    Kakigi, R; Shibasaki, H

    1987-01-01

    Generating mechanisms of giant somatosensory evoked potentials (SEPs) following stimulation of the posterior tibial nerve as well as the big toe were investigated in three patients with cortical reflex myoclonus. Scalp distributions of recognisable components were very similar to those in normal subjects, except that their amplitude was much larger. The tibial nerve SEPs were remarkably attenuated by interfering tactile stimulation. Therefore, the giant SEPs observed in the present cases seem...

  4. Reduced cerebrovascular reserve is regionally associated with cortical thickness reductions in children with sickle cell disease.

    Science.gov (United States)

    Kim, Junseok A; Leung, Jackie; Lerch, Jason P; Kassner, Andrea

    2016-07-01

    Sickle cell disease (SCD) is a genetic disorder which adversely affects cerebrovascular health. Previous studies have demonstrated regional cortical thinning in SCD. However, the reason behind regional reductions in cortical thickness remains unclear. Therefore, we aimed to explore the possible link between the state of cerebrovascular health and cortical thickness. In this study, we obtained magnetic resonance (MR) based measures of cerebrovascular reactivity (CVR), a measure of vascular health, and cortical thickness in SCD patients (N=60) and controls of similar age and similar gender ratio (N=27). The group comparison analysis revealed significant regionally specific reductions in CVR and cortical thickness in the SCD group compared to the controls. In addition, a regional association analysis was performed between CVR and cortical thickness in the SCD group which revealed a significant regional association in several brain regions with the highest strength of association observed in the left cuneus, right post central gyrus and the right temporal pole. The regional association analysis revealed that significant associations were found in brain regions with high metabolic activity (anterior cingulate, posterior cingulate, occipital gyrus, precuneus) thus demonstrating that these regions could be most vulnerable to structural damage under hypoxic conditions. PMID:27026656

  5. Monte Carlo analysis of skew posterior distributions: an econometric example

    OpenAIRE

    Dijk, Herman; Kloek, Teun

    1983-01-01

    textabstractThe posterior distribution of a small-scale illustrative econometric model is used to compare symmetric simple importance sampling with asymmetric simple importance sampling. The numerical results include posterior first and second order moments, numerical error estimates of the first order moments, posterior modes, univariate marginal posterior densities and bivariate marginal posterior densities plotted in three-dimensional figures.

  6. Biomechanical Consequences of Anterior Femoral Notching in Cruciate-Retaining Versus Posterior-Stabilized Total Knee Arthroplasty.

    Science.gov (United States)

    Jethanandani, Rishabh; Patwary, Mahbubul B; Shellito, Adam D; Meehan, John P; Amanatullah, Derek F

    2016-01-01

    Anterior femoral notching during total knee arthroplasty is a potential risk factor for periprosthetic supracondylar femur fracture. We conducted a study to determine if the design of the femoral implant changes the risk for periprosthetic supracondylar femur fractures after anterior cortical notching. An anterior cortical defect was created in 12 femoral polyurethane models. Six femora were instrumented with cruciate-retaining implants and 6 with posterior-stabilized implants. Each femur was loaded in external rotation along the anatomical axis. Notch depth and distance from anterior cortical notch to implant were recorded before loading, and fracture pattern was recorded after failure. There were no statistically significant differences in notch depth, distance from notch to implant, torsional stiffness, torque at failure, final torque, or fracture pattern between cruciate-retaining and posterior-stabilized femoral component designs. Periprosthetic fracture after anterior femoral notching is independent of the bone removed from the intercondylar notch. After notching, there likely is no significant difference in femoral strength in torsion between cruciate-retaining and posterior-stabilized designs. PMID:27552464

  7. Aggressive posterior retinopathy of prematurity classification

    Directory of Open Access Journals (Sweden)

    A.V. Tereshchenko,

    2013-02-01

    Full Text Available ABSTRACT Based on dynamic monitoring of 133 premature infants (266 eyes with aggressive posterior retinopathy of prematurity (ROP, digital retinoscopy and computer morphometry the disease clinical and morphometric features were revealed and systematized, and their consecutive replacement was fixed. As a result the separate classification of aggressive posterior disease was worked up. In aggressive posterior ROP course the next consecutive stages were marked out: subclinical, early clinical appearances stage, manifestation stage, advanced, far-advanced and terminal stages. The peculiarity of early clinical appearances stage and manifestation stage is the presence of such course types: favorable and unfavorable.

  8. DIAGNOSIS DAN PENATALAKSANAAN KATUP URETRA POSTERIOR

    Directory of Open Access Journals (Sweden)

    Putu Primeriana Nugiaswari

    2012-12-01

    Full Text Available Katup uretra posterior merupakan penyebab utama kesakitan, kematian, dan kerusakanginjal berkelanjutan pada anak-anak. Kelainan ini berupa lipatan mukosa abnormalkongenital pada uretra pars prostatika yang menyerupai membran tipis yangmenghambat drainase kandung kemih. Katup uretra posterior mayoritas didiagnosis saatprenatal melalui penggunaan ultrasonografi maternal. Tingkat keparahan dan derajatobstruksi yang disebabkan oleh kelainan ini tergantung pada konfigurasi dari membranobstruktif dalam uretra. Keputusan untuk mengintervensi saat prenatal didasarkan padausia kehamilan, volume cairan amnion, dan fungsi renal pada aspirasi urin fetus. Ablasikatup dengan endoskopi merupakan standar emas penanganan katup uretra posterior.

  9. Reversible posterior leukoencephalopathy syndrome in childhood: report of nine cases and review of the literature.

    Science.gov (United States)

    Gümüş, Hakan; Per, Hüseyin; Kumandaş, Sefer; Yikilmaz, Ali

    2010-04-01

    Reversible posterior leukoencephalopathy syndrome (RPLS) is recently described disorder with typical radiological findings in the posterior regions of the cerebral hemisphere and cerebellum. Its clinical symptoms include headache, decreased alertness, mental abnormalities, such as confusion, diminished spontaneity of speech, and changed behavior ranging from drowsiness to stupor, seizures, vomiting and abnormalities of visual perception like cortical blindness. RPLS is caused by various heterogeneous factors, the commonest being hypertension, followed by non-hypertensive causes such as eclampsia, renal diseases and immunosuppressive therapy. We presented nine patients with RPLS who had primary diagnoses such as acute post-streptococcal glomerulonephritis, idiopathic hypertension, the performing of intravenous immunoglobulin for infection with crescentic glomerulonephritis, erythrocyte transfusion for severe iron deficiency, L: -asparaginase treatment for acute lymphoblastic leukemia and performing of granulocyte-colony stimulating factor for ulcerative colitis due to neutropenia. Early recognition of RPLS as complication during different diseases and therapy in childhood may facilitate precise diagnosis and appropriate treatment. PMID:19809787

  10. Multilevel Cortical Processing of Somatosensory Novelty: A Magnetoencephalography Study

    Science.gov (United States)

    Naeije, Gilles; Vaulet, Thibaut; Wens, Vincent; Marty, Brice; Goldman, Serge; De Tiège, Xavier

    2016-01-01

    Using magnetoencephalography (MEG), this study investigates the spatio-temporal dynamics of the multilevel cortical processing of somatosensory change detection. Neuromagnetic signals of 16 healthy adult subjects (7 females and 9 males, mean age 29 ± 3 years) were recorded using whole-scalp-covering MEG while they underwent an oddball paradigm based on simple standard (right index fingertip tactile stimulation) and deviant (simultaneous right index fingertip and middle phalanx tactile stimulation) stimuli gathered into sequences to create and then deviate from stimulus patterns at multiple (local vs. global) levels of complexity. Five healthy adult subjects (3 females and 2 males, mean age 31, 6 ± 2 years) also underwent a similar oddball paradigm in which standard and deviant stimuli were flipped. Local deviations led to a somatosensory mismatch response peaking at 55–130 ms post-stimulus onset with a cortical generator located at the contralateral secondary somatosensory (cSII) cortex. The mismatch response was independent of the deviant stimuli physical characteristics. Global deviants led to a P300 response with cortical sources located bilaterally at temporo-parietal junction (TPJ) and supplementary motor area (SMA). The posterior parietal cortex (PPC) and the SMA were found to generate a contingent magnetic variation (CMV) attributed to top-down expectations. Amplitude of mismatch responses were modulated by top-down expectations and correlated with both the magnitude of the CMV and the P300 amplitude at the right TPJ. These results provide novel empirical evidence for a unified sensory novelty detection system in the human brain by linking detection of salient sensory stimuli in personal and extra-personal spaces to a common framework of multilevel cortical processing. PMID:27313523

  11. Multilevel cortical processing of somatosensory novelty: a magnetoencephalography study

    Directory of Open Access Journals (Sweden)

    Gilles eNaeije

    2016-06-01

    Full Text Available Using magnetoencephalography (MEG, this study investigates the spatio-temporal dynamics of the multilevel cortical processing of somatosensory change detection. Neuromagnetic signals of sixteen healthy adult subjects (7 females and 9 males, mean age 29 +/-3 y were recorded using whole-scalp-covering MEG while they underwent an oddball paradigm based on simple standard (right index fingertip tactile stimulation and deviant (simultaneous right index fingertip and middle phalanx tactile stimulation stimuli gathered into sequences to create and then deviate from stimulus patterns at multiple (local versus global levels of complexity. Five healthy adult subjects (3 females and 2 males, mean age 31,6 +/-2 y also underwent a similar oddball paradigm in which standard and deviant stimuli were flipped.Local deviations led to a somatosensory mismatch response peaking at 55-130 ms post-stimulus onset with a cortical generator located at the contralateral secondary somatosensory cortex. The mismatch response was independent of the deviant stimuli physical characteristics. Global deviants led to a P300 response with cortical sources located bilaterally at temporo-parietal junction (TPJ and supplementary motor area (SMA. The posterior parietal cortex (PPC and the SMA were found to generate a contingent magnetic variation (CMV attributed to top-down expectations. Amplitude of mismatch responses were modulated by top-down expectations and correlated with both the magnitude of the CMV and the P300 amplitude at the right TPJ. These results provide novel empirical evidence for a unified sensory novelty detection system in the human brain by linking detection of salient sensory stimuli in personal and extra-personal spaces to a common framework of multilevel cortical processing.

  12. Specialized pathways from the primate amygdala to posterior orbitofrontal cortex.

    Science.gov (United States)

    Timbie, Clare; Barbas, Helen

    2014-06-11

    The primate amygdala sends dense projections to posterior orbitofrontal cortex (pOFC) in pathways that are critical for processing emotional content, but the synaptic mechanisms are not understood. We addressed this issue by investigating pathways in rhesus monkeys (Macaca mulatta) from the amygdala to pOFC at the level of the system and synapse. Terminations from the amygdala were denser and larger in pOFC compared with the anterior cingulate cortex, which is also strongly connected with the amygdala. Axons from the amygdala terminated most densely in the upper layers of pOFC through large terminals. Most of these terminals innervated spines of presumed excitatory neurons and many were frequently multisynaptic and perforated, suggesting high synaptic efficacy. These amygdalar synapses in pOFC exceeded in size and specialization even thalamocortical terminals from the prefrontal-related thalamic mediodorsal nucleus to the middle cortical layers, which are thought to be highly efficient drivers of cortical neurons. Pathway terminals in the upper layers impinge on the apical dendrites of neurons in other layers, suggesting that the robust amygdalar projections may also activate neurons in layer 5 that project back to the amygdala and beyond to autonomic structures. Among inhibitory neurons, the amygdalar pathway innervated preferentially the neurochemical classes of calbindin and calretinin neurons in the upper layers of pOFC, which are synaptically suited to suppress noise and enhance signals. These features provide a circuit mechanism for flexibly shifting focus and adjusting emotional drive in processes disrupted in psychiatric disorders, such as phobias and obsessive-compulsive disorder. PMID:24920616

  13. Imprinting and recalling cortical ensembles.

    Science.gov (United States)

    Carrillo-Reid, Luis; Yang, Weijian; Bando, Yuki; Peterka, Darcy S; Yuste, Rafael

    2016-08-12

    Neuronal ensembles are coactive groups of neurons that may represent building blocks of cortical circuits. These ensembles could be formed by Hebbian plasticity, whereby synapses between coactive neurons are strengthened. Here we report that repetitive activation with two-photon optogenetics of neuronal populations from ensembles in the visual cortex of awake mice builds neuronal ensembles that recur spontaneously after being imprinted and do not disrupt preexisting ones. Moreover, imprinted ensembles can be recalled by single- cell stimulation and remain coactive on consecutive days. Our results demonstrate the persistent reconfiguration of cortical circuits by two-photon optogenetics into neuronal ensembles that can perform pattern completion. PMID:27516599

  14. Aspectos clínicos e concentração sérica da creatina-quinase e lactato-desidrogenase em cães submetidos à fisioterapia após atrofia muscular induzida Clinical aspects and serum concentration creatina kinase and lactate dehydrogenase in dogs submitted to physiotherapy after induced muscle atrophy

    OpenAIRE

    Soraia Figueiredo de Souza; João Guilherme Padilha Filho; Vera Maria Villamil Martins; Emílio de Almeida Belmonte; Nicole Maria Zanetti; Luis Gustavo Gosuen Gonçalves Dias; Bruna Piva Maria; Letícia Abrahão Anai; David José Miquelutti

    2011-01-01

    Avaliou-se a resposta de diferentes protocolos fisioterapêuticos em cães após a indução de atrofia muscular por meio da imobilização do joelho por 30 dias. Os grupos foram denominados grupo C ou controle, grupo E (massagem, movimentação passiva e eletroterapia), grupo H (massagem, movimentação passiva e hidroterapia em esteira aquática) e grupo EH (massagem, movimentação passiva, eletroterapia e hidroterapia em esteira aquática). Foram mensurados os graus de claudicação, arco do movimento, ci...

  15. Posterior alien hand syndrome: case report

    Energy Technology Data Exchange (ETDEWEB)

    Rohde, S.; Weidauer, S.; Lanfermann, H.; Zanella, F. [Institute of Neuroradiology, Johann Wolfgang Goethe University, Schleusenweg 2-16, 60528 Frankfurt am Main (Germany)

    2002-11-01

    The alien hand syndrome (AHS) is involuntary uncontrolled movement of an arm with a sense of estrangement from the limb itself. AHS was initially used to describe interhemispheric disconnection phenomena in patients with lesions in the anterior corpus callosum, but it has been found in patients with posterior cerebral lesions without involvement of the corpus callosum, for example parietal infarcts or corticobasal degeneration. The posterior alien hand syndrome is less frequent and presents with nonpurposive behaviour like lifting the arm or writhing fingers. We report an 80-year-old woman with a posterior AHS of the dominant right hand. MRI showed atrophy of the pre- and postcentral gyri without involvement of the corpus callosum. We discuss the aetiology of the posterior AHS and the differences from the anterior varieties. (orig.)

  16. Weakly supervised object detection with posterior regularization

    OpenAIRE

    Hakan Bilen; Marco Pedersoli; Tinne Tuytelaars

    2014-01-01

    Bilen H., Pedersoli M., Tuytelaars T., ''Weakly supervised object detection with posterior regularization'', 25th British machine vision conference - BMVC 2014, 12 pp., September 1-5, 2014, Nottingham, UK.

  17. Posterior alien hand syndrome: case report

    International Nuclear Information System (INIS)

    The alien hand syndrome (AHS) is involuntary uncontrolled movement of an arm with a sense of estrangement from the limb itself. AHS was initially used to describe interhemispheric disconnection phenomena in patients with lesions in the anterior corpus callosum, but it has been found in patients with posterior cerebral lesions without involvement of the corpus callosum, for example parietal infarcts or corticobasal degeneration. The posterior alien hand syndrome is less frequent and presents with nonpurposive behaviour like lifting the arm or writhing fingers. We report an 80-year-old woman with a posterior AHS of the dominant right hand. MRI showed atrophy of the pre- and postcentral gyri without involvement of the corpus callosum. We discuss the aetiology of the posterior AHS and the differences from the anterior varieties. (orig.)

  18. Cryptorchidism in boys with posterior urethral valves.

    Science.gov (United States)

    Krueger, R P; Hardy, B E; Churchill, B M

    1980-07-01

    A review of 207 male children with poterior urethral valves revealed an over-all incidence of cryptorchidism of 12 per cent. This association of cryptorchidism in boys with posterior urethral valves has not been described previously. PMID:6106069

  19. Posterior Fossa Tumors and Intellectual Impairment

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2005-01-01

    Full Text Available The effect of cerebellar damage on intellectual function in 76 children treated surgically for malignant posterior fossa tumor was investigated at the Gustave Roussy Institute, Villejuif, and the Department of Pediatric Neurosurgery, Necker Hospital, Paris, France.

  20. Cortical control of voluntary saccades in Parkinson's disease and pre-emptive perception.

    Science.gov (United States)

    Javaid, M A; Amassian, V; Glazman, S; Fesharaki, A; Stefanov, D; Bodis-Wollner, I

    2012-01-01

    Gamma range EEG has been associated with cognition. Bodis-Wollner et al. [Ann NY Acad Sci 2002;956:464-7] and Forgacs et al. [Perception 2008;37:419-32] described posterior perisaccadic gamma (35-45 Hz) modulation associated with voluntary saccades. Voluntary impairment is a hallmark of Parkinson's disease (PD). We have done correlational analysis of frontally and posteriorly (posterior-parietal) recorded intrasaccadic gamma (ISG) powers, to understand cortical control of voluntary saccades in PD and healthy controls. Fifteen PD patients (55-71 years, 4 females) and 17 healthy controls (54-72 years, 9 females) participated in the study. The EEG was recorded over frontal and posterior-parietal scalp sites. Saccades were recorded with electro-oculogram and infra-red ISCAN camera. Subjects executed horizontal voluntary saccades to a mark; 15 degree distance rightwards or leftwards (centrifugal CF) from the central fixation, then back to the center (centripetal CP) and so on, for 2 minutes. Perisaccadic EEG segments were wavelet transformed followed by Hilbert transform to obtain ISG (35-45 Hz) powers. ISG power was trial-averaged, separately for the 4 possible saccade types; CP and CF, rightwards and leftwards. The perisaccadic EEG revealed disorganization in the intrasaccadic period. The correlations between frontal and posterior ISG power are high in PD (correlation coefficient >0.6) while low in controls (correlation coefficient interpret these results as lack of modulatory coupling between frontal and posterior intrasaccadic mechanisms in PD. Impaired volition in PD may be due to impaired circuitry of preemptive perception (PEP). Interareal phase coupling analysis will help in investigating the cortical voluntary saccade control with greater temporal precision. PMID:22166401

  1. Kernel Bayesian Inference with Posterior Regularization

    OpenAIRE

    Song, Yang; Jun ZHU; Ren, Yong

    2016-01-01

    We propose a vector-valued regression problem whose solution is equivalent to the reproducing kernel Hilbert space (RKHS) embedding of the Bayesian posterior distribution. This equivalence provides a new understanding of kernel Bayesian inference. Moreover, the optimization problem induces a new regularization for the posterior embedding estimator, which is faster and has comparable performance to the squared regularization in kernel Bayes' rule. This regularization coincides with a former th...

  2. An unusual cause of posterior mediastinal cyst

    Directory of Open Access Journals (Sweden)

    Sahajal Dhooria

    2015-01-01

    Full Text Available Cystic lesions of the mediastinum may be congenital or acquired. The differential diagnosis depends on their location in the mediastinum. Cysts in the posterior mediastinum are generally developmental cysts and are neurogenic or of foregut origin. We report the case of a 14-year-old boy, who presented with dry cough and progressively increasing breathlessness, and was found to have a cystic lesion in the posterior mediastinum. Fine needle aspiration from the cyst helped make a diagnosis of tuberculosis.

  3. An unusual cause of posterior mediastinal cyst

    OpenAIRE

    Sahajal Dhooria; Valliappan Muthu; Ritesh Agarwal

    2015-01-01

    Cystic lesions of the mediastinum may be congenital or acquired. The differential diagnosis depends on their location in the mediastinum. Cysts in the posterior mediastinum are generally developmental cysts and are neurogenic or of foregut origin. We report the case of a 14-year-old boy, who presented with dry cough and progressively increasing breathlessness, and was found to have a cystic lesion in the posterior mediastinum. Fine needle aspiration from the cyst helped make a diagnosis of tu...

  4. Computer tomography of posterior cranial fossa

    Energy Technology Data Exchange (ETDEWEB)

    Sobota, J.; Dutka, J. (Ustredni Vojenska Nemocnice, Prague (Czechoslovakia))

    1982-11-01

    The problems and possibilities are presented of computer tomography examinations of the posterior cranial fossa. The apparatus used was Somatom 2 by Siemens. Such examinations make it possible to introduce specific measurements and evaluations of pathological processes. Computer tomography in itself, however, may not always be successful in this respect and in the examination of the posterior cranial fossa invasive methods, suitably used, will make the diagnosis more accurate and adequate therapy possible.

  5. Computer tomography of posterior cranial fossa

    International Nuclear Information System (INIS)

    The problems and possibilities are presented of computer tomography examinations of the posterior cranial fossa. The apparatus used was Somatom 2 by Siemens. Such examinations make it possible to introduce specific measurements and evaluations of pathological processes. Computer tomography in itself, however, may not always be successful in this respect and in the examination of the posterior cranial fossa invasive methods, suitably used, will make the diagnosis more accurate and adequate therapy possible. (J.O.)

  6. Posterior atlantoaxial dislocation without associated fracture

    International Nuclear Information System (INIS)

    We report on a 38-year-old man with post-traumatic posterior displacement of the atlas with respect to the axis without any associated fracture or neurological deficit caused by the displacement. Radiographs, computed tomography (CT) and magnetic resonance imaging (MRI) revealed posterior displacement of the atlas with the odontoid peg lying anterior and to the right of the anterior arch of the atlas. (orig.)

  7. Delayed Single Stage Perineal Posterior Urethroplasty

    International Nuclear Information System (INIS)

    Objective: To determine the delayed single stage perineal posterior urethroplasty for treatment of posterior urethral stricture/distraction defect. Study Design: Descriptive case series. Place and Duration of Study: Department of Urology, Jinnah Postgraduate Medical Centre, Karachi, from January 2009 to December 2011. Methodology: Patients were selected for delayed single stage perineal posterior urethroplasty for treatment of posterior urethral stricture / distraction defect. All were initially suprapubically catheterized followed by definitive surgery after at least 3 months. Results: Thirty male patients were analyzed with a mean follow-up of 10 months, 2 patients were excluded as they developed failure in first 3 months postoperatively. Mean patients age was 26.25 ± 7.9 years. On follow-up, 7 patients (23.3 percentage) experienced recurrent stricture during first 10 months. Five (16.6 percentage) patients were treated successfully with single direct visual internal urethrotomy. Two patients (6.6 percentage) had more than one direct visual internal urethrotomy and considered failed. Re-do perineal urethroplasty was eventually performed. The overall success rate was 93.3 percentage with permissive criteria allowing single direct visual internal urethrotomy and 76.6% with strict criteria allowing no more procedures postoperatively. Conclusion: Posterior anastomotic urethroplasty offers excellent long-term results to patients with posterior urethral trauma and distraction defect even after multiple prior procedures. (author)

  8. Skin to posterior lumbar epidural space distance

    International Nuclear Information System (INIS)

    To measure the clinically relevant skin to posterior lumbar epidural space distance in adult surgical patients and to correlate this distance with the patient physical factors to construct a model for the prediction of this distance using the correlation. The study was carried out in 100 patients divided into three groups, who were scheduled for different surgical procedures. Group-I consisted of female patients scheduled for lower segment caesarian section (L.S.C.S); group-II adult non-pregnant females undergoing elective surgery and group-III adult males undergoing different surgical procedures. Epidural anaesthesia was given, using loss of resistance (LOR) technique, and skin to posterior epidural space was measured. The mean skin to posterior lumbar epidural space distance was found to be 3.8 +- 0.5 cm in group-I, 3.76 +- 0.7 cm in group- II and 4.0 +- 0.5 cm in group-III. Skin to posterior epidural space distance correlates best with weight of the patient. Posterior lumbar skin to epidural space distance has been found to be less than what is normal in rest of the world. These results may be used as a guideline for performing successful epidural blocks in Pakistani population. A reliable model using patient physical factors to predict skin to posterior epidural space distance could not be constructed. (author)

  9. Echocardiographic Wall Motion Abnormality in Posterior Myocardial Infarction: The Diagnostic Value of Posterior Leads

    Directory of Open Access Journals (Sweden)

    A Darehzereshki

    2008-06-01

    Full Text Available Background: For the purpose of ascertaining myocardial infarction (MI and ischemia, the sensitivity of the initial 12-lead ECG is inadequate. It is risky to diagnose posterior MI using only precordial reciprocal changes, since the other leads may be more optimally positioned for the identification of electrocardiographic changes. In this study, we evaluated the relationship between electrocardiography changes and wall motion abnormalities in patients with posterior MI for earlier and better diagnosis of posterior MI.Methods: In this prospective cross-sectional study, we enrolled patients with posterior MI who had come to the Emergency Department of Shariati Hospital with their first episode of chest pain. A 12-lead surface electrocardiogram using posterior leads (V7-V9 was performed for all participants. Patients with ST elevation >0.05 mV or pathologic Q wave in the posterior leads, as well as those with specific changes indicating posterior MI in V1-V2, were evaluated by echocardiography in terms of wall motion abnormalities. All data were analyzed using SPSS and p<0.05 were considered statistically significant.Results: Of a total 79 patients enrolled, 48 (60.8% were men, and the mean age was 57.35±8.22 years. Smoking (54.4% and diabetes (48% were the most prevalent risk factors. In the echocardiographic evaluation, all patients had wall motion abnormalities in the left ventricle and 19 patients (24.1% had wall motion abnormalities in the right ventricle. The most frequent segment with motion abnormality among the all patients was the mid-posterior. The posterior leads showed better positive predictive value than the anterior leads for posterior wall motion abnormality.Conclusion: Electrocardiography of the posterior leads in patients with acute chest pain can help in earlier diagnosis and in time treatment of posterior MI.

  10. Cortical deafness in multiple sclerosis

    OpenAIRE

    Tabira, T.; Tsuji, S; Nagashima, T; T. Nakajima; Kuroiwa, Y

    1981-01-01

    Cortical deafness in a patient with multiple sclerosis is reported. Complete recovery from total deafness was seen following stages of auditory agnosia and pure word deafness. The otological and neurophysiological studies suggested lesions in subcortical white matter. This report stresses the rarity of the condition, its subcortical origin and good prognosis.

  11. Stress Distribution on Short Implants at Maxillary Posterior Alveolar Bone Model With Different Bone-to-Implant Contact Ratio: Finite Element Analysis.

    Science.gov (United States)

    Yazicioglu, Duygu; Bayram, Burak; Oguz, Yener; Cinar, Duygu; Uckan, Sina

    2016-02-01

    The aim of this study was to evaluate the stress distribution of the short dental implants and bone-to-implant contact ratios in the posterior maxilla using 3-dimensional (3D) finite element models. Two different 3D maxillary posterior bone segments were modeled. Group 1 was composed of a bone segment consisting of cortical bone and type IV cancellous bone with 100% bone-to-implant contact. Group 2 was composed of a bone segment consisting of cortical bone and type IV cancellous bone including spherical bone design and homogenous tubular hollow spaced structures with 30% spherical porosities and 70% bone-to-implant contact ratio. Four-millimeter-diameter and 5-mm-height dental implants were assumed to be osseointegrated and placed at the center of the segments. Lateral occlusal bite force (300 N) was applied at a 25° inclination to the implants long axis. The maximum von Mises stresses in cortical and cancellous bones and implant-abutment complex were calculated. The von Mises stress values on the implants and the cancellous bone around the implants of the 70% bone-to-implant contact group were almost 3 times higher compared with the values of the 100% bone-to-implant contact group. For clinical reality, use of the 70% model for finite element analysis simulation of the posterior maxilla region better represents real alveolar bone and the increased stress and strain distributions evaluated on the cortical and cancellous bone around the dental implants. PMID:26867093

  12. Posterior reversible leukoencephalopathy syndrome in children with hematologic disorders

    Directory of Open Access Journals (Sweden)

    Barış Malbora

    2010-09-01

    Full Text Available Objective: Posterior reversible leukoencephalopathy syndrome (PRES is characterized by headache, altered mental status, cortical blindness, and seizures associated with neuroradiological findings. It involves predominantly white matter of the parieto-occipital lobes. Several medications and disorders play a role in the etiology of PRES. In this study, we aimed to show how the prognosis of PRES in hematological diseases of childhood might be according to the etiological factors.Materials and Methods: Here, we report PRES in six patients, aged 4 to 14 years, with diagnoses of leukemia and aplastic anemia. Results: Suggested causes in our patients were chemotherapeutics, hypertension, infection and antimicrobial drug administration, tumor lysis syndrome, acute renal failure and hemodialysis, immunosuppressive drug administration, and hypomagnesemia. One of the patients died of sepsis, renal failure and pulmonary hemorrhage and another died of relapse after total recovery from PRES. The other four patients are under follow-up without problems. Conclusion: We suggest that PRES can recover fully with early diagnosis and treatment whereas it can show poor prognosis depending on the etiology.

  13. Sp8 and COUP-TF1 reciprocally regulate patterning and Fgf signaling in cortical progenitors.

    Science.gov (United States)

    Borello, Ugo; Madhavan, Mayur; Vilinsky, Ilya; Faedo, Andrea; Pierani, Alessandra; Rubenstein, John; Campbell, Kenneth

    2014-06-01

    To gain new insights into the transcriptional regulation of cortical development, we examined the role of the transcription factor Sp8, which is downstream of Fgf8 signaling and known to promote rostral cortical development. We have used a binary transgenic system to express Sp8 throughout the mouse telencephalon in a temporally restricted manner. Our results show that misexpression of Sp8 throughout the telencephalon, at early but not late embryonic stages, results in cortical hypoplasia, which is accompanied by increased cell death, reduced proliferation, and precocious neuronal differentiation. Misexpression of Sp8 at early developmental stages represses COUP-TF1 expression, a negative effector of Fgf signaling and a key promoter of posterior cortical identity, while ablation of Sp8 has the opposite effect. In addition, transgenic misexpression of COUP-TF1 resulted in downregulation of Sp8, indicating a reciprocal cross-regulation between these 2 transcription factors. Although Sp8 has been suggested to induce and/or maintain Fgf8 expression in the embryonic telencephalon, neither Fgf8 nor Fgf15 was upregulated using our gain-of-function approach. However, misexpression of Sp8 greatly increased the expression of Fgf target molecules, suggesting enhanced Fgf signaling. Thus, we propose that Sp8 promotes rostral and dorsomedial cortical development by repressing COUP-TF1 and promoting Fgf signaling in pallial progenitors. PMID:23307639

  14. Cortico-Cortical Interactions during Acquisition and Use of a Neuroprosthetic Skill

    Science.gov (United States)

    Wander, Jeremiah D.; Sarma, Devapratim; Johnson, Lise A.; Fetz, Eberhard E.; Rao, Rajesh P. N.; Ojemann, Jeffrey G.; Darvas, Felix

    2016-01-01

    A motor cortex-based brain-computer interface (BCI) creates a novel real world output directly from cortical activity. Use of a BCI has been demonstrated to be a learned skill that involves recruitment of neural populations that are directly linked to BCI control as well as those that are not. The nature of interactions between these populations, however, remains largely unknown. Here, we employed a data-driven approach to assess the interaction between both local and remote cortical areas during the use of an electrocorticographic BCI, a method which allows direct sampling of cortical surface potentials. Comparing the area controlling the BCI with remote areas, we evaluated relationships between the amplitude envelopes of band limited powers as well as non-linear phase-phase interactions. We found amplitude-amplitude interactions in the high gamma (HG, 70–150 Hz) range that were primarily located in the posterior portion of the frontal lobe, near the controlling site, and non-linear phase-phase interactions involving multiple frequencies (cross-frequency coupling between 8–11 Hz and 70–90 Hz) taking place over larger cortical distances. Further, strength of the amplitude-amplitude interactions decreased with time, whereas the phase-phase interactions did not. These findings suggest multiple modes of cortical communication taking place during BCI use that are specialized for function and depend on interaction distance. PMID:27541829

  15. A Circuit for Motor Cortical Modulation of Auditory Cortical Activity

    OpenAIRE

    Nelson, Anders; Schneider, David M.; Takatoh, Jun; Sakurai, Katsuyasu; Wang, Fan; Mooney, Richard

    2013-01-01

    Normal hearing depends on the ability to distinguish self-generated sounds from other sounds, and this ability is thought to involve neural circuits that convey copies of motor command signals to various levels of the auditory system. Although such interactions at the cortical level are believed to facilitate auditory comprehension during movements and drive auditory hallucinations in pathological states, the synaptic organization and function of circuitry linking the motor and auditory corti...

  16. Cortical Signature of Patients with HBV-related Cirrhosis without Overt Hepatic Encephalopathy: a Morphometric Analysis

    Directory of Open Access Journals (Sweden)

    Xiu Wu

    2015-06-01

    Full Text Available Previous studies have shown that patients with hepatitis B virus-related cirrhosis (HBV-RC without overt hepatic encephalopathy (OHE are associated with a varying degree of cognitive dysfunction. Several resting-state functional magnetic resonance imaging (fMRI studies have been conducted to explore the neural correlates of such cognitive deficits, whereas little effort has been made to investigate the cortical integrity in cirrhotic patients without OHE. Here, using cortical thickness, surface area and local gyrification index (lGI, this study performed a comprehensive analysis on the cortical morphometry of patients with HBV-RC without OHE (HBV-RC-NOHE versus matched healthy controls. Compared with healthy controls, we found significantly increased cortical thickness in the bilateral lingual and parahippocampal gyrus, right posterior cingulate cortex, precuneus, peri-calcarine sulcus and fusiform gyrus in patient with HBV-RC-NOHE, which may closely relate to be the low-grade brain edema. Cortical gyrification analysis showed significantly increased lGI in the left superior and inferior parietal cortex as well as lateral occipital cortex, which was speculated to be associated with disruptions in white matter connectivity and sub-optimal intra-cortical organization. In addition, the mean cortical thickness/lGI of the regions with structural abnormalities was shown to be negatively correlated with psychometric hepatic encephalopathy score (PHES of the patients with HBV-RC-NOHE. These morphological changes may serve as potential markers for the preclinical diagnosis and progression of HBV-RC-NOHE.

  17. Parallel Cortical Networks Formed by Modular Organization of Primary Motor Cortex Outputs.

    Science.gov (United States)

    Hamadjida, Adjia; Dea, Melvin; Deffeyes, Joan; Quessy, Stephan; Dancause, Numa

    2016-07-11

    In primates, the refinement of motor behaviors, in particular hand use, is associated with the establishment of more direct projections from primary motor cortex (M1) onto cervical motoneurons [1, 2] and the appearance of additional premotor and sensory cortical areas [3]. All of these areas have reciprocal connections with M1 [4-7]. Thus, during the evolution of the sensorimotor network, the number of interlocutors with which M1 interacts has tremendously increased. It is not clear how these additional interconnections are organized in relation to one another within the hand representation of M1. This is important because the organization of connections between M1 and phylogenetically newer and specialized cortical areas is likely to be key to the increased repertoire of hand movements in primates. In cebus monkeys, we used injections of retrograde tracers into the hand representation of different cortical areas of the sensorimotor network (ventral and dorsal premotor areas [PMv and PMd], supplementary motor area [SMA], and posterior parietal cortex [area 5]), and we analyzed the pattern of labeled neurons within the hand representation of M1. Instead of being uniformly dispersed across M1, neurons sending projections to each distant cortical area were largely segregated in different subregions of M1. These data support the view that primates split the cortical real estate of M1 into modules, each preferentially interconnected with a particular cortical area within the sensorimotor network. This modular organization could sustain parallel processing of interactions with multiple specialized cortical areas to increase the behavioral repertoire of the hand. PMID:27322001

  18. Pars plana vitrectomy with posterior iris claw implantation for posteriorly dislocated nucleus and intraocular lens

    Directory of Open Access Journals (Sweden)

    Kishor B Patil

    2011-01-01

    Full Text Available We evaluated the safety and efficacy of pars plana vitrectomy (PPV with primary posterior iris claw intraocular lens (IOL implantation in cases of posterior dislocation of nucleus and IOL without capsular support. This was a retrospective interventional case series. Fifteen eyes underwent PPV with primary posterior iris claw IOL implantation performed by a single vitreoretinal surgeon. The main outcome measures were changes in best corrected visual acuity and anterior and posterior segment complications. A total of 15 eyes were included in this study. Eight had nucleus drop, three had IOL drop during cataract surgery and four had traumatic posterior dislocation of lens. The final postoperative best corrected visual acuity was 20/60 or better in 11 patients. This procedure is a viable option in achieving good functional visual acuity in eyes without capsular support.

  19. The cat's meow: A high-field fMRI assessment of cortical activity in response to vocalizations and complex auditory stimuli.

    Science.gov (United States)

    Hall, Amee J; Butler, Blake E; Lomber, Stephen G

    2016-02-15

    Sensory systems are typically constructed in a hierarchical fashion such that lower level subcortical and cortical areas process basic stimulus features, while higher level areas reassemble these features into object-level representations. A number of anatomical pathway tracing studies have suggested that the auditory cortical hierarchy of the cat extends from a core region, consisting of the primary auditory cortex (A1) and the anterior auditory field (AAF), to higher level auditory fields that are located ventrally. Unfortunately, limitations on electrophysiological examination of these higher level fields have resulted in an incomplete understanding of the functional organization of the auditory cortex. Thus, the current study uses functional MRI in conjunction with a variety of simple and complex auditory stimuli to provide the first comprehensive examination of function across the entire cortical hierarchy. Auditory cortex function is shown to be largely lateralized to the left hemisphere, and is concentrated bilaterally in fields surrounding the posterior ectosylvian sulcus. The use of narrowband noise stimuli enables the visualization of tonotopic gradients in the posterior auditory field (PAF) and ventral posterior auditory field (VPAF) that have previously been unverifiable using fMRI and pure tones. Furthermore, auditory fields that are inaccessible to more invasive techniques, such as the insular (IN) and temporal (T) cortices, are shown to be selectively responsive to vocalizations. Collectively, these data provide a much needed functional correlate for anatomical examinations of the hierarchy of cortical structures within the cat auditory cortex. PMID:26658927

  20. Giant dumbbell tumor of the posterior mediastinum

    Directory of Open Access Journals (Sweden)

    Milosavljević Miloš Z.

    2009-01-01

    Full Text Available Background. Giant dumbbell-shaped tumors are very rare and characterized by intra- and extraspinal propagation of different dimensions. In thoracal localization, invasive growth can lead up to rib and vertebra erosion. Case report. We presented a 54-year-old woman with a giant dumbbell schwannoma in the posterior mediastinum. The tumor was removed by the posterior approach with hemilaminectomy and costotransversectomy. By microscopic examination the diagnosis of benign schwannoma was made. A year after the surgery, the patient was without neurological deficiency and without radiological signs of illness relapse. Conclusion. Treatment of dumbbell schwannoma is surgical, dilemmas of the optimal surgical approach. When it is thoracally located the posterior approach with hemilaminectomy and costotransversectomy is safe and effective for its removal.

  1. Anomalous posterior clinoid process and its clinical importance

    OpenAIRE

    Shipra Paul; Srijit Das

    2007-01-01

    The anterior, middle and the posterior clinoid processes are located in the middle cranial fossa of the skull. The posterior boundary of the pituitary fossa is formed by the dorsum sellae, the supero-lateral angles of which are raised to form the posterior clinoid process. Unlike the anterior clinoid process, the posterior clinoid process has received less attention in past research studies. The anatomy textbooks do not mention about the anomalies pertaining to the posterior clinoid process a...

  2. Anomalous posterior clinoid process and its clinical importance.

    OpenAIRE

    Shipra Paul; Srijit Das

    2009-01-01

    The anterior, middle and the posterior clinoid processes are located in the middle cranial fossa of the skull. The posterior boundary of the pituitary fossa is formed by the dorsum sellae, the supero-lateral angles of which are raised to form the posterior clinoid process. Unlike the anterior clinoid process, the posterior clinoid process has received less attention in past research studies. The anatomy textbooks do not mention about the anomalies pertaining to the posterior clinoid process a...

  3. Infantile cortical Hyperostosis; Caffey's disease

    International Nuclear Information System (INIS)

    Five cases of Caffey's disease (infantile cortical hyperostosis) diagnosed at the children's hospital radiology department between 1988-1996 are presented. The presentation age was 3 years and five months. Symptomatology consisted in fever, soft tissue edema and irritability. All patients had mandibular compromise, in two patients the mandibular compromise was isolated the others had poliostotic compromise the radiological changes were characteristic of this entity

  4. Cortical Microstimulation for Neural Prostheses

    OpenAIRE

    Venkatraman, Subramaniam

    2010-01-01

    Brain-controlled prostheses have the potential to improve the quality of life of a large number of paralyzed persons by allowing them to control prosthetic limbs simply by thought. An essential requirement for natural use of such neural prostheses is that the user should be provided with somatosensory feedback from the artificial limb. This can be achieved by electrically stimulating small populations of neurons in the cortex; a process known as cortical microstimulation. This dissertation de...

  5. The origin of cortical neurons

    OpenAIRE

    Parnavelas J.G.

    2002-01-01

    Neurons of the mammalian cerebral cortex comprise two broad classes: pyramidal neurons, which project to distant targets, and the inhibitory nonpyramidal cells, the cortical interneurons. Pyramidal neurons are generated in the germinal ventricular zone, which lines the lateral ventricles, and migrate along the processes of radial glial cells to their positions in the developing cortex in an `inside-out' sequence. The GABA-containing nonpyramidal cells originate for the most part in the gangli...

  6. Posterior leukoencephalopathy syndrome in poststretococcal acute glomerulonephritis

    International Nuclear Information System (INIS)

    Reversible posterior leukoencephalopathy (LEPR) is a clinical entity that affects radiation usually the white matter of the cerebral hemispheres. It is frequently associated with acute arterial hypertension and immunosuppressive therapy, among other causes. The clinical presentation is varied, with headache, nausea, vomiting, impaired consciousness and abnormal behavior, seizures and visual disturbances, symptoms that often regress. Computed tomography (CT) and magnetic resonance imaging (MRI) images show white matter edema predominantly in posterior regions of the brain. We present a 10 year old boy with leprosy in the course of a nephrotic syndrome secondary to acute diffuse glomerunefritis (GNDA) poststreptococcal. (author)

  7. Imaging the posterior mediastinum: a multimodality approach.

    Science.gov (United States)

    Occhipinti, Mariaelena; Heidinger, Benedikt H; Franquet, Elisa; Eisenberg, Ronald L; Bankier, Alexander A

    2015-01-01

    The posterior mediastinum contains several structures that can produce a wide variety of pathologic conditions. Descending thoracic aorta, esophagus, azygos and hemiazygos veins, thoracic duct, lymph nodes, adipose tissue, and nerves are all located in this anatomical region and can produce diverse abnormalities. Although chest radiography may detect many of these pathologic conditions, computed tomography and magnetic resonance are the imaging modalities of choice for further defining the relationship of posterior mediastinal lesions to neighboring structures and showing specific imaging features that narrow the differential diagnosis. This review emphasizes modality-related answers to morphologic questions, which provide precise diagnostic information. PMID:25993732

  8. Desarrollo neuromuscular en la atrofia muscular espinal

    OpenAIRE

    Martínez Hernàndez, Rebeca

    2012-01-01

    BACKGROUND: Spinal muscular atrophy (SMA) is a neuromuscular disease characterized by degeneration and loss of spinal cord motor neurons leading to denervation and muscular atrophy. It is caused by defects in the Survival Motor Neuron 1 gene (SMN1) and it is classified by age of onset and motor milestones into three main types which strongly correlate with the copy number of its homologous gene, SMN2. SMN2 expresses markedly less full‐length protein than SMN1, provoking disease manifestations...

  9. Regional Patterns of Cortical Phase Synchrony in the Resting State.

    Science.gov (United States)

    Casimo, Kaitlyn; Darvas, Felix; Wander, Jeremiah; Ko, Andrew; Grabowski, Thomas J; Novotny, Edward; Poliakov, Andrew; Ojemann, Jeffrey G; Weaver, Kurt E

    2016-07-01

    Synchronized phase estimates between oscillating neuronal signals at the macroscale level reflect coordinated activities between neuronal assemblies. Recent electrophysiological evidence suggests the presence of significant spontaneous phase synchrony within the resting state. The purpose of this study was to investigate phase synchrony, including directional interactions, in resting state subdural electrocorticographic recordings to better characterize patterns of regional phase interactions across the lateral cortical surface during the resting state. We estimated spontaneous phase locking value (PLV) as a measure of functional connectivity, and phase slope index (PSI) as a measure of pseudo-causal phase interactions, across a broad range of canonical frequency bands and the modulation of the amplitude envelope of high gamma (amHG), a band that is believed to best reflect the physiological processes giving rise to the functional magnetic resonance imaging BOLD signal. Long-distance interactions had higher PLVs in slower frequencies (≤theta) than in higher ones (≥beta) with amHG behaving more like slow frequencies, and a general trend of increasing frequency band of significant PLVs when moving across the lateral surface along an anterior-posterior axis. Moreover, there was a strong trend of frontal-to-parietal directional phase synchronization, measured by PSI across multiple frequencies. These findings, which are likely indicative of coordinated and structured spontaneous cortical interactions, are important in the study of time scales and directional nature of resting state functional connectivity, and may ultimately contribute to a better understanding of how spontaneous synchrony is linked to variation in regional architecture across the lateral cortical surface. PMID:27019319

  10. Pain Catastrophising Affects Cortical Responses to Viewing Pain in Others.

    Directory of Open Access Journals (Sweden)

    Nicholas Fallon

    Full Text Available Pain catastrophising is an exaggerated cognitive attitude implemented during pain or when thinking about pain. Catastrophising was previously associated with increased pain severity, emotional distress and disability in chronic pain patients, and is also a contributing factor in the development of neuropathic pain. To investigate the neural basis of how pain catastrophising affects pain observed in others, we acquired EEG data in groups of participants with high (High-Cat or low (Low-Cat pain catastrophising scores during viewing of pain scenes and graphically matched pictures not depicting imminent pain. The High-Cat group attributed greater pain to both pain and non-pain pictures. Source dipole analysis of event-related potentials during picture viewing revealed activations in the left (PHGL and right (PHGR paraphippocampal gyri, rostral anterior (rACC and posterior cingulate (PCC cortices. The late source activity (600-1100 ms in PHGL and PCC was augmented in High-Cat, relative to Low-Cat, participants. Conversely, greater source activity was observed in the Low-Cat group during the mid-latency window (280-450 ms in the rACC and PCC. Low-Cat subjects demonstrated a significantly stronger correlation between source activity in PCC and pain and arousal ratings in the long latency window, relative to high pain catastrophisers. Results suggest augmented activation of limbic cortex and higher order pain processing cortical regions during the late processing period in high pain catastrophisers viewing both types of pictures. This pattern of cortical activations is consistent with the distorted and magnified cognitive appraisal of pain threats in high pain catastrophisers. In contrast, high pain catastrophising individuals exhibit a diminished response during the mid-latency period when attentional and top-down resources are ascribed to observed pain.

  11. Promotion of Cortical Neurogenesis from the Neural Stem Cells in the Adult Mouse Subcallosal Zone.

    Science.gov (United States)

    Kim, Joo Yeon; Choi, Kyuhyun; Shaker, Mohammed R; Lee, Ju-Hyun; Lee, Boram; Lee, Eunsoo; Park, Jae-Yong; Lim, Mi-Sun; Park, Chang-Hwan; Shin, Ki Soon; Kim, Hyun; Geum, Dongho; Sun, Woong

    2016-04-01

    Neurogenesis occurs spontaneously in the subventricular zone (SVZ) of the lateral ventricle in adult rodent brain, but it has long been debated whether there is sufficient adult neurogenesis in human SVZ. Subcallosal zone (SCZ), a posterior continuum of SVZ closely associated with posterior regions of cortical white matter, has also been reported to contain adult neural stem cells (aNSCs) in both rodents and humans. However, little is known whether SCZ-derived aNSC (SCZ-aNSCs) can produce cortical neurons following brain injury. We found that SCZ-aNSCs exhibited limited neuronal differentiation potential in culture and after transplantation in mice. Neuroblasts derived from SCZ initially migrated toward injured cortex regions following brain injury, but later exhibited apoptosis. Overexpression of anti-apoptotic bcl-xL in the SCZ by retroviral infection rescued neuroblasts from cell death in the injured cortex, but neuronal maturation was still limited, resulting in atrophy. In combination with Bcl-xL, infusion of brain-derived neurotropic factor rescued atrophy, and importantly, a subset of such SCZ-aNSCs differentiated and attained morphological and physiological characteristics of mature, excitatory neurons. These results suggest that the combination of anti-apoptotic and neurotrophic factors might enable the use of aNSCs derived from the SCZ in cortical neurogenesis for neural replacement therapy. Stem Cells 2016;34:888-901. PMID:26701067

  12. Image-based retrieval system and computer-aided diagnosis system for renal cortical scintigraphy images

    Science.gov (United States)

    Mumcuoğlu, Erkan; Nar, Fatih; Uğur, Omer; Bozkurt, M. Fani; Aslan, Mehmet

    2008-03-01

    Cortical renal (kidney) scintigraphy images are 2D images (256x256) acquired in three projection angles (posterior, right-posterior-oblique and left-posterior-oblique). These images are used by nuclear medicine specialists to examine the functional morphology of kidney parenchyma. The main visual features examined in reading the images are: size, location, shape and activity distribution (pixel intensity distribution within the boundary of each kidney). Among the above features, activity distribution (in finding scars if any) was found to have the least interobserver reproducibility. Therefore, in this study, we developed an image-based retrieval (IBR) and a computer-based diagnosis (CAD) system, focused on this feature in particular. The developed IBR and CAD algorithms start with automatic segmentation, boundary and landmark detection. Then, shape and activity distribution features are computed. Activity distribution feature is obtained using the acquired image and image set statistics of the normal patients. Active Shape Model (ASM) technique is used for more accurate kidney segmentation. In the training step of ASM, normal patient images are used. Retrieval performance is evaluated by calculating precision and recall. CAD performance is evaluated by specificity and sensitivity. To our knowledge, this paper is the first IBR or CAD system reported in the literature on renal cortical scintigraphy images.

  13. Measurements of evoked electroencephalograph by transcranial magnetic stimulation applied to motor cortex and posterior parietal cortex

    Science.gov (United States)

    Iwahashi, Masakuni; Koyama, Yohei; Hyodo, Akira; Hayami, Takehito; Ueno, Shoogo; Iramina, Keiji

    2009-04-01

    To investigate the functional connectivity, the evoked potentials by stimulating at the motor cortex, the posterior parietal cortex, and the cerebellum by transcranial magnetic stimulation (TMS) were measured. It is difficult to measure the evoked electroencephalograph (EEG) by the magnetic stimulation because of the large artifact induced by the magnetic pulse. We used an EEG measurement system with sample-and-hold circuit and an independent component analysis to eliminate the electromagnetic interaction emitted from TMS. It was possible to measure EEG signals from all electrodes over the head within 10 ms after applying the TMS. When the motor area was stimulated by TMS, the spread of evoked electrical activity to the contralateral hemisphere was observed at 20 ms after stimulation. However, when the posterior parietal cortex was stimulated, the evoked electrical activity to the contralateral hemisphere was not observed. When the cerebellum was stimulated, the cortical activity propagated from the stimulated point to the frontal area and the contralateral hemisphere at around 20 ms after stimulation. These results suggest that the motor area has a strong interhemispheric connection and the posterior parietal cortex has no interhemispheric connection.

  14. True Giant Posterior Tibial Artery Aneurysm

    OpenAIRE

    Patrizio Colotto; Gabriele Testi; Giacomo Di Iasio; Alessandro Robaldo

    2012-01-01

    We report an unusual case of true atherosclerotic posterior tibial artery (PTA) aneurysm without any apparent causative history. To our knowledge, in the English Literature only seven previously cases of true PTA aneurysms are reported. Due to its location, this lesion may require surgical intervention and removal. The presentation, the diagnostic evaluation, and the surgical management of the aneurysm are discussed.

  15. [Therapy of posterior and posterolateral knee instability].

    Science.gov (United States)

    Jakob, R P; Rüegsegger, M

    1993-11-01

    The natural course after posterior cruciate ligament (PCL) tear is a slow process of degeneration starting in the medial compartment. Functional disability is mainly present in those instabilities that are combined with posterolateral insufficiency. The surgical treatment at present mainly addresses these combined types of posterior-posterolateral instability. It is generally agreed that suture of the torn PCL alone is insufficient and augmentation with autologous structures, such as the patellar ligament, are mandatory. Synthetic augmentation to facilitate after treatment is another adjunct. Because of the difficulty of precise tibial tunnel placement a two-stage procedure is advocated, an anterior approach with the patient supine being used for femoral graft placement. If a posterior approach with the patient prone is used, a straight posterior incision is made between the two heads of the gastrocnemius and the neuromuscular bundle. With this approach the tibial bone block is placed in a trough. The accuracy of graft placement and the immediate functional aftertreatment facilitated by the use of osseous fixation of a synthetic augmentation device at both ends have made better results of surgical reconstruction of the PCL possible. PMID:8309701

  16. Posterior dislocation of the shoulder joint

    Directory of Open Access Journals (Sweden)

    Thakker Tejas

    2006-01-01

    Full Text Available Background: Posterior dislocation of shoulder is a rather uncommon injury that is often not diagnosed at the initial examination. However certain constant clinical signs may lead the examiner to suspect the presence of this condition. Even the routine antero-posterior roentgenogram may provide a few clues to diagnosis but the axillary view is mandatory to verify diagnosis. Material and methods : We report a series of 15 shoulders (14 patients with a locked posterior dislocation. Electric shock (7 patients, vehicular accident (4 patients and epileptic seizure (3 patients was causes of dislocation in these patients. The diagnosis was missed initially in 10 cases. An axillary radiograph confirmed the diagnosis in all. Treatment consisted of closed reduction, which was successful in 5, Neer′s modification of McLaughlin procedure (transfer of subscapularis in 6, hemireplacement arthroplasty in one shoulder and tuberosity fixation in one patient. Results : Follow-up ranged from 1 year to 4 years. Five patients had excellent, five good, two poor and one had fair result. Conclusion : Key to diagnosis is a high index of suspicion. The prognosis became less favorable and the therapeutic difficulties were found to be increased in direct proportion to the length of time, these lesions remain undiagnosed. With early recognisition of dislocation, prompt reduction is relatively easy. Surgical intervention is necessary for old unreduced posterior dislocations.

  17. Posterior skulderluksation--en diagnostisk udfordring

    DEFF Research Database (Denmark)

    Trollegaard, Anton Mitchell

    2009-01-01

    A case of posterior shoulder dislocation is described. The dislocation was misinterpreted twice clinically and radiographically in two different casualty departments before it was diagnosed and treated with closed reposition in a third facility. Treatment was conservative and the arm was placed in...

  18. Restoration of the endodontically treated posterior tooth

    Directory of Open Access Journals (Sweden)

    Andrea Polesel

    2014-06-01

    Results and conclusions: Direct adhesive restorations, indirect bonded restorations and traditional full crown are three therapeutic options for the single posterior endodontically treated teeth. The amount of remaining sound tooth structure is the most significant factor influencing the therapeutic approach. The clinician's operative skill is a determining aspect for long-term success of adhesive inlays.

  19. New concepts on posterior fossa malformations

    Energy Technology Data Exchange (ETDEWEB)

    Jaspan, Tim [Imaging Centre, University Hospital, Nottingham (United Kingdom)

    2008-06-15

    A full description of the embryology of the posterior fossa (PF) is beyond the scope of this review; several recent publications are recommended. Specific aspects of the processes involved are, however, reviewed as a background to malformations that involve defects or errors occurring at critical stages during the embryogenesis of the PF structures. (orig.)

  20. Acute Posterior Ischemic Optic Neuropathy Mimicking Posterior Cerebral Artery Stroke Visualized by 3-Tesla MRI

    Directory of Open Access Journals (Sweden)

    Tilman Menzel

    2012-11-01

    Full Text Available Acute ischemic lesions of the posterior optic nerve and optic tract can produce a variety of visual field defects. A 71-year-old woman presented with acute hemianopia, which led to rt-PA thrombolysis for suspected posterior cerebral artery ischemia. 3-Tesla cMRI, however, revealed the cause to be an acute posterior ischemic optic neuropathy. Cases like this may be more common than thought and quite regularly overlooked in clinical practice, especially when there is no high-resolution MRI available. This case strengthens the importance of repeat MR imaging in patients with persistent visual field defects.

  1. Acute Posterior Ischemic Optic Neuropathy Mimicking Posterior Cerebral Artery Stroke Visualized by 3-Tesla MRI

    OpenAIRE

    Menzel, Tilman; Kern, Rolf; Griebe, Martin; Hennerici, Michael; Fatar, Marc

    2012-01-01

    Acute ischemic lesions of the posterior optic nerve and optic tract can produce a variety of visual field defects. A 71-year-old woman presented with acute hemianopia, which led to rt-PA thrombolysis for suspected posterior cerebral artery ischemia. 3-Tesla cMRI, however, revealed the cause to be an acute posterior ischemic optic neuropathy. Cases like this may be more common than thought and quite regularly overlooked in clinical practice, especially when there is no high-resolution MRI avai...

  2. Imaging findings in posterior instability of the shoulder

    International Nuclear Information System (INIS)

    Posterior shoulder instability refers to the symptoms and signs resulting from excessive posterior translation of the humerus. Magnetic resonance (MR) imaging is the radiological modality of choice in the diagnostic assessment of posterior instability. Computed tomography (CT) is useful in the evaluation of osseous abnormalities associated with posterior instability. A detailed description of the posterior osseous and labroligamentous abnormalities has evolved recently, and many variant lesions of the posteroinferior labrum and/or capsular structures have been described. As the recommended surgical management of lesions associated with posterior instability is a lesion-specific approach, awareness of the specific lesions that have been described in association with posterior instability helps in pre-surgical planning. The purpose of this article is to review the classification of, and injury mechanisms leading to, posterior shoulder instability and to describe imaging findings associated with posterior instability, with emphasis on MR imaging. (orig.)

  3. The relationship between cerebral infarction on MR and angiographic findings in moyamoya disease: significance of the posterior circulation

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Eun Ja; Song, Soon Young [College of Medicine, Kwangdong Univ., Koyang (Korea, Republic of); Yu, Won Jong; Jung, So Lyung; Chung, Bong Gak; Kag, Si Won [College of Medicine, The Catholic Univ. of Korea, Seoul (Korea, Republic of); Kim, Man Deuk [College of Medicine, Pochon CHA Univ., Pochon (Korea, Republic of)

    2002-06-01

    To investigate the relationship between changes in the posterior and anterior circulation, as seen at angiography, and the frequency and extent of cerebral infarction revealed by MR imaging in moyamoya disease. This study involved 34 patients (22 females and 12 males, aged 2-52 years) in whom cerebral angiography revealed the presence of moyamoya disease (bilateral; unilateral= 24:10; total hemispheres=58) and who also underwent brain MR imaging. To evaluate the angiographic findings, we applied each angiographic staging system to the anterior and posterior circulation. Leptomeningeal collateral circulation from the cortical branches of the posterior cerebral artery (PCA) was also assigned one of four grades. At MR imaging, areas of cerebral cortical or subcortical infarction in the hemisphere were divided into six zones. White matter and basal ganglionic infarction, ventricular dilatation, cortical atrophy, and hemorrhagic lesions were also evaluated. To demonstrate the statistical significance of the relationship between the angiographic and the MR findings, both the Mantel-Haenszel chi-square test for trend and the chi-square test were used. The degree of steno-occlusive PCA change correlated significantly with the internal carotid artery (ICA) stage (p<0.0001). As PCA stages advanced, the degree of leptomeningeal collaterals from the PCA decreased significantly (P<0.0001), but ICA stages were not significant (p>0.05). The prevalence of infarction showed significant correlation with the degree of steno-occlusive change in both the ICA and PCA. The degree of cerebral ischemia in moyamoya patients increased proportionally with the severity of PCA stenosis rather than with that of steno-occlusive lesins of the anterior circulation. Infarctions tended to be distributed in the anterior part of the hemisphere at PCA state I or II, while in more advanced PCA lesions, they were also found posteriorly, especially in the territories of the posterior middle cerebral artery

  4. The relationship between cerebral infarction on MR and angiographic findings in moyamoya disease: significance of the posterior circulation

    International Nuclear Information System (INIS)

    To investigate the relationship between changes in the posterior and anterior circulation, as seen at angiography, and the frequency and extent of cerebral infarction revealed by MR imaging in moyamoya disease. This study involved 34 patients (22 females and 12 males, aged 2-52 years) in whom cerebral angiography revealed the presence of moyamoya disease (bilateral; unilateral= 24:10; total hemispheres=58) and who also underwent brain MR imaging. To evaluate the angiographic findings, we applied each angiographic staging system to the anterior and posterior circulation. Leptomeningeal collateral circulation from the cortical branches of the posterior cerebral artery (PCA) was also assigned one of four grades. At MR imaging, areas of cerebral cortical or subcortical infarction in the hemisphere were divided into six zones. White matter and basal ganglionic infarction, ventricular dilatation, cortical atrophy, and hemorrhagic lesions were also evaluated. To demonstrate the statistical significance of the relationship between the angiographic and the MR findings, both the Mantel-Haenszel chi-square test for trend and the chi-square test were used. The degree of steno-occlusive PCA change correlated significantly with the internal carotid artery (ICA) stage (p0.05). The prevalence of infarction showed significant correlation with the degree of steno-occlusive change in both the ICA and PCA. The degree of cerebral ischemia in moyamoya patients increased proportionally with the severity of PCA stenosis rather than with that of steno-occlusive lesins of the anterior circulation. Infarctions tended to be distributed in the anterior part of the hemisphere at PCA state I or II, while in more advanced PCA lesions, they were also found posteriorly, especially in the territories of the posterior middle cerebral artery (MCA), the posterior border zone, and the PCA (p0.05). The degree of steno-occlusive lesions of the PCA correlated with the ICA stage. Progressive changes in

  5. Hamilton-Jacobi skeleton on cortical surfaces.

    Science.gov (United States)

    Shi, Y; Thompson, P M; Dinov, I; Toga, A W

    2008-05-01

    In this paper, we propose a new method to construct graphical representations of cortical folding patterns by computing skeletons on triangulated cortical surfaces. In our approach, a cortical surface is first partitioned into sulcal and gyral regions via the solution of a variational problem using graph cuts, which can guarantee global optimality. After that, we extend the method of Hamilton-Jacobi skeleton [1] to subsets of triangulated surfaces, together with a geometrically intuitive pruning process that can trade off between skeleton complexity and the completeness of representing folding patterns. Compared with previous work that uses skeletons of 3-D volumes to represent sulcal patterns, the skeletons on cortical surfaces can be easily decomposed into branches and provide a simpler way to construct graphical representations of cortical morphometry. In our experiments, we demonstrate our method on two different cortical surface models, its ability of capturing major sulcal patterns and its application to compute skeletons of gyral regions. PMID:18450539

  6. Circadian regulation of human cortical excitability.

    Science.gov (United States)

    Ly, Julien Q M; Gaggioni, Giulia; Chellappa, Sarah L; Papachilleos, Soterios; Brzozowski, Alexandre; Borsu, Chloé; Rosanova, Mario; Sarasso, Simone; Middleton, Benita; Luxen, André; Archer, Simon N; Phillips, Christophe; Dijk, Derk-Jan; Maquet, Pierre; Massimini, Marcello; Vandewalle, Gilles

    2016-01-01

    Prolonged wakefulness alters cortical excitability, which is essential for proper brain function and cognition. However, besides prior wakefulness, brain function and cognition are also affected by circadian rhythmicity. Whether the regulation of cognition involves a circadian impact on cortical excitability is unknown. Here, we assessed cortical excitability from scalp electroencephalography (EEG) responses to transcranial magnetic stimulation in 22 participants during 29 h of wakefulness under constant conditions. Data reveal robust circadian dynamics of cortical excitability that are strongest in those individuals with highest endocrine markers of circadian amplitude. In addition, the time course of cortical excitability correlates with changes in EEG synchronization and cognitive performance. These results demonstrate that the crucial factor for cortical excitability, and basic brain function in general, is the balance between circadian rhythmicity and sleep need, rather than sleep homoeostasis alone. These findings have implications for clinical applications such as non-invasive brain stimulation in neurorehabilitation. PMID:27339884

  7. Atrofia muscular bulbo espinhal recessiva ligada ao cromossomo X (doença de Kennedy: estudo de uma família X-linked recessive bulbospinal muscular atrophy (Kennedy's disease: study of a family

    Directory of Open Access Journals (Sweden)

    DAMACIO RAMÓN KAIMEN-MACIEL

    1998-09-01

    Full Text Available A doença de Kennedy (DK é forma rara de doença do neurônio motor caracterizada por mutação na região codificadora do gene do receptor androgênico localizado no braço longo do cromossoma X (Xq 11-12. Há expansão das sequências de trinucleotídeos CAG que nos pacientes deve atingir número maior do que 347 repetições de pares de bases. Apresentamos quatro gerações de uma família com dez indivíduos acometidos. Avaliamos três pacientes do sexo masculino com idade variando entre 50 e 60 anos que desenvolveram sintomatologia por volta de 30 anos de idade caracterizada por fraqueza muscular progressiva associada a disfagia e disartria. O exame demonstrou ginecomastia, atrofia testicular, amiotrofia, fasciculações, paresia, abolição de reflexos e tremor postural. A análise do DNA pela técnica do PCR demonstrou número de repetições CAG aumentado no locus Xq 11-12 nos três pacientes e em uma mulher assintomática da família. Demonstramos a primeira família brasileira com diagnóstico de DK através de genética molecular. A DK deve fazer parte do diagnóstico diferencial das doenças do neurônio motor e a identificação destes pacientes é importante para o prognóstico e para o aconselhamento genético.Kennedy's disease is a rare type of motor neuron disease with a sex-linked recessive trait. DNA studies show a mutation at the androgen receptor gene on the long arm of X cromossome (Xq 11-12 with expanded CAG triplets (more than 347 repeats. We present three patients and one carrier among ten patients of a four generation family with clinical phenotype of the disease. The patients' ages ranged from 50 to 60 years with symptomatology usually beginning around 30 years of age. Patients had gynecomastia, testicular atrophy, muscular weakness, fasciculation, amyotrophy, absent deep tendon reflexes and postural tremor. PCR techniques of DNA analysis showed expanded size of CAG repeats on Xq 11-12 in all the three patients and in

  8. Avaliação fonoaudiológica na atrofia de múltiplos sistemas: estudo com cinco pacientes Multiple system atrophy speech assessment: study of five cases

    Directory of Open Access Journals (Sweden)

    Denise Botelho Knopp

    2002-09-01

    Full Text Available A atrofia de múltiplos sistemas (AMS é caracterizada pela presença de sinais parkinsonianos, cerebelares, autonômicos e piramidais, em várias combinações. O aparecimento de disartria e disfagia no primeiro ano de manifestação de parkinsonismo, sugere o diagnóstico de AMS. O objetivo deste estudo foi o de caracterizar do ponto de vista fonoaudiológico os distúrbios da fala e da voz dos pacientes com AMS. Foram selecionados cinco pacientes, com idade média de 51,2 anos e com diagnóstico provável de AMS. Cada paciente foi submetido a avaliação neurológica e fonoaudiológica. Esta última foi composta dos seguintes itens: anamnese; avaliação miofuncional e avaliação perceptivo-auditiva da fala. Os sintomas de fala e voz apareceram 1,1 ano após o início dos sintomas motores e a disartrofonia apresentada por todos os pacientes foi a do tipo mista, mesclando os componentes hipocinético, atáxico e espástico, com predomínio do primeiro. Nossos achados são diferentes daqueles comumente vistos em pacientes com a doença de Parkinson, onde o componente hipocinético é o único achado. Os dados levantados indicam que a avaliação fonoaudiológica é importante no diagnóstico diferencial e no planejamento terapêutico da AMS.Multiple system atrophy (MSA is characterized by parkinsonian, cerebellar and pyramidal features along with autonomic dysfunction in different combinations. Onset of dysarthria during the first year of the manifestation of a parkinsonian syndrome suggests the diagnosis of MSA. The aim of this study was to characterize the voice and the speech of patients with MSA. We studied five MSA patients with a mean age of 51.2 years. Each patient was submitted to a neurological and a specific speech and voice assessment. The latter consisted of the following: clinical interview, myofunctional examination, and perceptual speech evaluation. Speech and voice complaints occurred at an average time of 1.1 year after the

  9. Communication and wiring in the cortical connectome

    OpenAIRE

    Budd, Julian M. L.; Kisvárday, Zoltán F.

    2012-01-01

    In cerebral cortex, the huge mass of axonal wiring that carries information between near and distant neurons is thought to provide the neural substrate for cognitive and perceptual function. The goal of mapping the connectivity of cortical axons at different spatial scales, the cortical connectome, is to trace the paths of information flow in cerebral cortex. To appreciate the relationship between the connectome and cortical function, we need to discover the nature and purpose of the wiring p...

  10. Communication and Wiring in the Cortical Connectome

    OpenAIRE

    Julian Budd; Zoltan F Kisvarday

    2012-01-01

    In cerebral cortex, the huge mass of axonal wiring that carries information between near and distant neurons is thought to provide the neural substrate for cognitive and perceptual function. The goal of mapping the connectivity of cortical axons at different spatial scales, the cortical connectome, is to trace the paths of information flow in cerebral cortex. To appreciate the relationship between the connectome and cortical function, we need to discover the nature and purpose of the wiring p...

  11. Patterned activity within the local cortical architecture

    OpenAIRE

    Farran Briggs

    2010-01-01

    The cerebral cortex is a vastly complex structure consisting of multiple distinct populations of neurons residing in functionally specialized cortical compartments. A fundamental goal in systems neuroscience is to understand the interactions among cortical neurons and their relationship to behavior. It is hypothesized that dynamic activity patterns, such as oscillations in global neuronal activity, could span large, heterogeneous populations of cortical neurons in such a manner as to bind t...

  12. Communication and Wiring in the Cortical Connectome

    Directory of Open Access Journals (Sweden)

    Julian Budd

    2012-10-01

    Full Text Available In cerebral cortex, the huge mass of axonal wiring that carries information between near and distant neurons is thought to provide the neural substrate for cognitive and perceptual function. The goal of mapping the connectivity of cortical axons at different spatial scales, the cortical connectome, is to trace the paths of information flow in cerebral cortex. To appreciate the relationship between the connectome and cortical function, we need to discover the nature and purpose of the wiring principles underlying cortical connectivity. A popular explanation has been that axonal length is strictly minimized both within and between cortical regions. In contrast, we have hypothesized the existence of a multi-scale principle of cortical wiring where to optimise communication there is a trade-off between spatial (construction and temporal (routing costs. Here, using recent evidence concerning cortical spatial networks we critically evaluate this hypothesis at neuron, local circuit, and pathway scales. We report three main conclusions. First, the axonal and dendritic arbor morphology of single neocortical neurons may be governed by a similar wiring principle, one that balances the conservation of cellular material and conduction delay. Second, the same principle may be observed for fibre tracts connecting cortical regions. Third, the absence of sufficient local circuit data currently prohibits any meaningful assessment of the hypothesis at this scale of cortical organization. To avoid neglecting neuron and microcircuit levels of cortical organization, the connectome framework should incorporate more morphological description. In addition, structural analyses of temporal cost for cortical circuits should take account of both axonal conduction and neuronal integration delays, which appear mostly of the same order of magnitude. We conclude the hypothesized trade-off between spatial and temporal costs may potentially offer a powerful explanation for

  13. An Unusual Cause of Posterior Elbow Impingement: Detachment of a Hypertrophied Posterior Fat Pad

    Directory of Open Access Journals (Sweden)

    Daisuke Hamada

    2015-01-01

    Full Text Available We report a case of a 47-year-old woman who developed posterior impingement of the elbow due to detachment of a hypertrophied posterior fat pad. She reported acute left elbow pain after leaning back onto a hard object with her hand and subsequently experienced a “catching” sensation. Comparison with the magnetic resonance images of a normal elbow revealed a hypertrophied posterior fat pad interposed between the olecranon and olecranon fossa in both elbows, with the fat pad in the left elbow located more inferiorly than that in the right elbow. Elbow arthroscopy showed the olecranon fossa covered by the fat pad, a portion of which was detached from the rest of the pad. Debridement of the detached portion was performed until no impingement was evident. Postoperatively, full extension of the elbow did not elicit pain. Clinicians should include this pathology among the differential diagnoses for posterior elbow pain.

  14. Posterior cruciate-retaining versus posterior-stabilized total knee arthroplasty: a meta-analysis.

    Science.gov (United States)

    Bercik, Michael J; Joshi, Ashish; Parvizi, Javad

    2013-03-01

    The objective of this meta-analysis was to compare outcomes of posterior cruciate-retaining and posterior stabilized prostheses. A computerized literature search was conducted to identify randomized controlled trials comparing the clinical outcomes of cruciate-retaining and posterior-stabilized designs. The table of contents of four major Orthopaedic journals and the references section of two arthroplasty text books were reviewed to identify other relevant studies. Ultimately, 1114 patients (1265 knees) were compared. Statistical analysis revealed a significant difference in flexion and range of motion in favor of posterior-stabilized knees, but no difference in complication rates. The clinical importance of this remains unknown. The decision to use one design versus the other should rest with the surgeon's preference and comfort with a particular design. PMID:23433255

  15. Cortical necrosis of the renal transplant

    International Nuclear Information System (INIS)

    Cortical necrosis is a rare complication of renal transplants, which requires urgent diagnosis and management to avoid unnecessary immunosuppression. Seven renal transplants with suspected cortical necrosis were evaluated by Doppler-US, 99mTc-DTPA-perfusion study and Gd-DTPA-enhanced dynamic MRI. In four transplants, cortical necrosis was confirmed by angiography and histology. In diagnosing cortical necrosis with preserved medullary perfusion (n=2) dynamic MRI was superior to the other modalities. Totally necrotic renal transplants (n=2) were reliably diagnosed by all imaging methods. (orig.)

  16. Posterior Pole Sparing Laser Photocoagulation Combined with Intravitreal Bevacizumab Injection in Posterior Retinopathy of Prematurity

    OpenAIRE

    2014-01-01

    Purpose. To report the results of the posterior pole sparing laser photocoagulation combined with intravitreal bevacizumab injection (IVB) in retinopathy of prematurity (ROP). Methods. A retrospective chart review of premature babies with ROP, all of whom received laser photocoagulation with IVB. Eleven eyes of 6 infants with advanced zone I ROP underwent laser ablation sparing posterior pole with concurrent IVB. The results were compared with those of full-laser treatment combined with IVB t...

  17. Posterior Pole Sparing Laser Photocoagulation Combined with Intravitreal Bevacizumab Injection in Posterior Retinopathy of Prematurity

    Directory of Open Access Journals (Sweden)

    Rebecca Kim

    2014-01-01

    Full Text Available Purpose. To report the results of the posterior pole sparing laser photocoagulation combined with intravitreal bevacizumab injection (IVB in retinopathy of prematurity (ROP. Methods. A retrospective chart review of premature babies with ROP, all of whom received laser photocoagulation with IVB. Eleven eyes of 6 infants with advanced zone I ROP underwent laser ablation sparing posterior pole with concurrent IVB. The results were compared with those of full-laser treatment combined with IVB to 8 eyes of 5 infants with advanced ROP without involvement of the posterior pole. Results. The posterior pole sparing laser with IVB was performed with zone I, stage 3+ ROP at the mean postmenstrual age of 36 weeks and 5 days. The plus sign decreased significantly at postoperative day 1, the neovascular proliferation regressed by postoperative week 1, and the normal vascularization started at postoperative day 32 on the average. Two months after treatment, vascularization of the spared avascular area was completed. There was no macular dragging, tractional retinal detachment, foveal destruction by laser scars, or any other adverse event. No significant anatomical differences were identified from those of full-laser ablation combined with IVB. Conclusions. Posterior pole sparing laser with IVB can give favorable results without destruction of posterior pole retina.

  18. Intrinsic connections and architectonics of posterior parietal cortex in the rhesus monkey

    International Nuclear Information System (INIS)

    By means of autoradiographic and ablation-degeneration techniques, the intrinsic cortical connections of the posterior parietal cortex in the rhesus monkey were traced and correlated with a reappraisal of cerebral architectonics. Two major rostral-to-caudal connectional sequences exist. One begins in the dorsal postcentral gyrus (area 2) and proceeds, through architectonic divisions of the superior parietal lobule (areas PE and PEc), to a cortical region on the medial surface of the parietal lobe (area PGm). This area has architectonic features similar to those of the caudal inferior parietal lobule (area PG). The second sequence begins in the ventral post/central gyrus (area 2) and passes through the rostral inferior parietal lobule (areas PG and PFG) to reach the caudal inferior parietal lobule (area PG). Both the superior parietal lobule and the rostral inferior parietal lobule also send projections to various other zones located in the parietal opercular region, the intraparietal sulcus, and the caudalmost portion of the cingulate sulcus. Areas PGm and PG, on the other hand, project to each other, to the cingulate region, to the caudalmost portion of the superior temporal gyrus, and to the upper bank of the superior temporal sulcus. Finally, a reciprocal sequence of connections, directed from caudal to rostral, links together many of the above-mentioned parietal zones. With regard to the laminar pattern of termination, the rostral-to-caudal connections are primarily distributed in the form of cortical ''columns'' while the caudal-to-rostral connections are found mainly over the first cortical cell layer

  19. Sleep deficits in mild cognitive impairment are related to increased levels of plasma amyloid-β and cortical thinning.

    Science.gov (United States)

    Sanchez-Espinosa, Mayely P; Atienza, Mercedes; Cantero, Jose L

    2014-09-01

    Evidence suggests that amyloid-beta (Aβ) depositions parallel sleep deficits in Alzheimer's disease (AD). However, it remains unknown whether impaired sleep and changes in plasma Aβ levels are related in amnestic mild cognitive impairment (aMCI) subjects, and whether both markers are further associated with cortical thinning in canonical AD regions. To jointly address this issue, we investigated relationships between changes in physiological sleep and plasma Aβ concentrations in 21 healthy old (HO) adults and 21 aMCI subjects, and further assessed whether these two factors were associated with cortical loss in each group. aMCI, but not HO subjects, showed significant relationships between disrupted slow-wave sleep (SWS) and increased plasma levels of Aβ42. We also found that shortened rapid-eye movement (REM) sleep in aMCI correlated with thinning of the posterior cingulate, precuneus, and postcentral gyrus; whereas higher levels of Aβ40 and Aβ42 accounted for grey matter (GM) loss of posterior cingulate and entorhinal cortex, respectively. These results support preliminary relationships between Aβ burden and altered sleep physiology observed in animal models of AD amyloidosis, and provide precise cortical correlates of these changes in older adults with aMCI. Taken together, these findings open new research avenues on the combined role of sleep, peripheral Aβ levels and cortical integrity in tracking the progression from normal aging to early neurodegeneration. PMID:24845621

  20. Cortical control of facial expression.

    Science.gov (United States)

    Müri, René M

    2016-06-01

    The present Review deals with the motor control of facial expressions in humans. Facial expressions are a central part of human communication. Emotional face expressions have a crucial role in human nonverbal behavior, allowing a rapid transfer of information between individuals. Facial expressions can be either voluntarily or emotionally controlled. Recent studies in nonhuman primates and humans have revealed that the motor control of facial expressions has a distributed neural representation. At least five cortical regions on the medial and lateral aspects of each hemisphere are involved: the primary motor cortex, the ventral lateral premotor cortex, the supplementary motor area on the medial wall, and the rostral and caudal cingulate cortex. The results of studies in humans and nonhuman primates suggest that the innervation of the face is bilaterally controlled for the upper part and mainly contralaterally controlled for the lower part. Furthermore, the primary motor cortex, the ventral lateral premotor cortex, and the supplementary motor area are essential for the voluntary control of facial expressions. In contrast, the cingulate cortical areas are important for emotional expression, because they receive input from different structures of the limbic system. J. Comp. Neurol. 524:1578-1585, 2016. © 2015 Wiley Periodicals, Inc. PMID:26418049

  1. SLEEP AND OLFACTORY CORTICAL PLASTICITY

    Directory of Open Access Journals (Sweden)

    Dylan Barnes

    2014-04-01

    Full Text Available In many systems, sleep plays a vital role in memory consolidation and synaptic homeostasis. These processes together help store information of biological significance and reset synaptic circuits to facilitate acquisition of information in the future. In this review, we describe recent evidence of sleep-dependent changes in olfactory system structure and function which contribute to odor memory and perception. During slow-wave sleep, the piriform cortex becomes hypo-responsive to odor stimulation and instead displays sharp-wave activity similar to that observed within the hippocampal formation. Furthermore, the functional connectivity between the piriform cortex and other cortical and limbic regions is enhanced during slow-wave sleep compared to waking. This combination of conditions may allow odor memory consolidation to occur during a state of reduced external interference and facilitate association of odor memories with stored hedonic and contextual cues. Evidence consistent with sleep-dependent odor replay within olfactory cortical circuits is presented. These data suggest that both the strength and precision of odor memories is sleep-dependent. The work further emphasizes the critical role of synaptic plasticity and memory in not only odor memory but also basic odor perception. The work also suggests a possible link between sleep disturbances that are frequently co-morbid with a wide range of pathologies including Alzheimer’s disease, schizophrenia and depression and the known olfactory impairments associated with those disorders.

  2. Gyrification from constrained cortical expansion

    CERN Document Server

    Tallinen, Tuomas; Biggins, John S; Mahadevan, L

    2015-01-01

    The exterior of the mammalian brain - the cerebral cortex - has a conserved layered structure whose thickness varies little across species. However, selection pressures over evolutionary time scales have led to cortices that have a large surface area to volume ratio in some organisms, with the result that the brain is strongly convoluted into sulci and gyri. Here we show that the gyrification can arise as a nonlinear consequence of a simple mechanical instability driven by tangential expansion of the gray matter constrained by the white matter. A physical mimic of the process using a layered swelling gel captures the essence of the mechanism, and numerical simulations of the brain treated as a soft solid lead to the formation of cusped sulci and smooth gyri similar to those in the brain. The resulting gyrification patterns are a function of relative cortical expansion and relative thickness (compared with brain size), and are consistent with observations of a wide range of brains, ranging from smooth to highl...

  3. Acupuncture modulates cortical thickness and functional connectivity in knee osteoarthritis patients.

    Science.gov (United States)

    Chen, Xiaoyan; Spaeth, Rosa B; Retzepi, Kallirroi; Ott, Daniel; Kong, Jian

    2014-01-01

    In this study, we investigated cortical thickness and functional connectivity across longitudinal acupuncture treatments in patients with knee osteoarthritis (OA). Over a period of four weeks (six treatments), we collected resting state functional magnetic resonance imaging (fMRI) scans from 30 patients before their first, third and sixth treatments. Clinical outcome showed a significantly greater Knee Injury and Osteoarthritis Outcome Score (KOOS) pain score (improvement) with verum acupuncture compared to the sham acupuncture. Longitudinal cortical thickness analysis showed that the cortical thickness at left posterior medial prefrontal cortex (pMPFC) decreased significantly in the sham group across treatment sessions as compared with verum group. Resting state functional connectivity (rsFC) analysis using the left pMPFC as a seed showed that after longitudinal treatments, the rsFC between the left pMPFC and the rostral anterior cingulate cortex (rACC), medial frontal pole (mFP) and periaquiduct grey (PAG) are significantly greater in the verum acupuncture group as compared with the sham group. Our results suggest that acupuncture may achieve its therapeutic effect on knee OA pain by preventing cortical thinning and decreases in functional connectivity in major pain related areas, therefore modulating pain in the descending pain modulatory pathway. PMID:25258037

  4. Right Cortical and Axonal Structures Eliciting Ocular Deviation During Electrical Stimulation Mapping in Awake Patients.

    Science.gov (United States)

    Montemurro, Nicola; Herbet, Guillaume; Duffau, Hugues

    2016-07-01

    To investigate the neural network underpinning eye movements, a cortical and subcortical intraoperative mapping using direct electrical stimulation (DES) was achieved in six awake patients during surgery for a right frontal low-grade glioma. We assessed the relationship between the occurrence of ocular deviation during both cortical and axonal DES and the anatomic location for each response. The corresponding stimulation sites were reported on a standard brain template for visual analysis and between-subjects comparisons. Our results showed that DES of the cortical frontal eye field (FEF) elicited horizontal (anterior FEF) or upward (posterior FEF) eye movements in 3 patients, supporting the fact that FEF comprises several distinct functional subregions. In addition, subcortical stimulation of the white matter tracts underneath the FEF evoked conjugate contraversive ocular deviation in 3 other patients. Interestingly, this region seems to be a crossroad between the fronto-striatal tract, the frontal aslant tract, the inferior fronto-occipital fascicle and the superior longitudinal fascicle. No deficits in eye movements were observed following surgery. To our knowledge, this is the first study reporting ocular deviation during axonal electrostimulation mapping of the white matter fibers in awake patients. Therefore, our original data issued from DES give new insights into the cortical and subcortical structures involved in the control of eye movements and their strong relationships with other functional pathways. PMID:27067598

  5. Long range frontal/posterior phase synchronization during remembered pursuit task is impaired in schizophrenia.

    Science.gov (United States)

    Krishna, Nithin; O'Neill, Hugh; Sánchez-Morla, Eva María; Thaker, Gunvant K

    2014-08-01

    Although smooth pursuit eye movement (SPEM) is a reliable endophenotype of schizophrenia, exact underlying cognitive and neural substrates remain unknown. A simple mechanistic model of SPEM assumes an efficient interaction in integrating sensory input from the medial temporal (MT)/medial superior temporal (MST) brain regions and subsequent motor response through the frontal eye field (FEF). Poor functional connectivity between these two regions could explain impaired motion perception and SPEM maintenance in schizophrenia. In the present study, we combined an eye tracking paradigm with electroencephalography (EEG) recordings to investigate the putative functional connectivity among frontal/posterior brain regions in mediating the modulation of SPEM. Twenty four schizophrenic (SZ) and 22 healthy control (HC) participants performed remembered pursuit tasks with EEG recordings. Behaviorally, HC subjects showed significant improvement in SPEM response on repeated presentations of target compared to SZ subjects. Neurophysiologically HC subjects showed higher frontal/posterior phase synchronization in the beta to low gamma range frequency bands during all target presentations. In addition there was a significant increase in phase synchronization in the beta-2 frequency band in HC subjects during late compared to early target presentation. In contrast, higher frontal/posterior phase synchronization in the beta-2 frequency predicted better performance during late target presentation and lower enduring psychosis in SZ subjects. These data suggest a pathologically perturbed connectivity between frontal and posterior cortical regions during SPEM in SZ. The integrative eye tracking-EEG approach used in this study to dissect the endophenotype may reveal novel targets for studying schizophrenia psychopathology. PMID:24951402

  6. CT of posterior ocular staphyloma in axial myopia

    International Nuclear Information System (INIS)

    We present two cases of posterior ocular staphylomas in axial myopia. CT findings of an enlarged globe with focal posterior bulging and scleraluveal rim thinning appear to be specific for this diagnosis. (orig.)

  7. CT of posterior ocular staphyloma in axial myopia

    Energy Technology Data Exchange (ETDEWEB)

    Swayne, L.C.; Garfinkle, W.B.; Bennett, R.H.

    1984-05-01

    We present two cases of posterior ocular staphylomas in axial myopia. CT findings of an enlarged globe with focal posterior bulging and scleraluveal rim thinning appear to be specific for this diagnosis.

  8. Posterior reversible encephalopathy syndrome: A case report

    Directory of Open Access Journals (Sweden)

    Kostić Dejan

    2015-01-01

    Full Text Available Posterior reversible encephalopathy syndrome (PRES is characterized by the following symptoms: seizures, impaired consciousness and/or vision, vomiting, nausea, and focal neurological signs. Diagnostic imaging includes examination by magnetic resonance (MR and computed tomography (CT, where brain edema is visualized bi-laterally and symmetrically, predominantly posteriorly, parietally, and occipitally. Case report. We presented a 73-year-old patient with the years-long medical history of hipertension and renal insufficiency, who developed PRES with the symptomatology of the rear cranium. CT and MR verified changes in the white matter involving all lobes on both sides of the brain. After a two-week treatment (antihypertensive, hypolipemic and rehydration therapy clinical improvement with no complications occurred, with complete resolution of changes in the white matter observed on CT and MR. Conclusion. PRES is a reversible syndrome in which the symptoms withdraw after several days to several weeks if early diagnosis is made and appropriate treatment started without delay.

  9. Assessment of mandibular posterior regional landmarks using cone-beam computed tomography in dental implant surgery.

    Science.gov (United States)

    de Souza, Lílian Azevedo; Souza Picorelli Assis, Neuza Maria; Ribeiro, Rosangela Almeida; Pires Carvalho, Antônio Carlos; Devito, Karina Lopes

    2016-05-01

    The aim of this study has been to evaluate and correlate the anatomical features of the posterior mandibular region (submandibular fossa depth, bone height and thickness, and mandibular canal corticalization) to improve accident prevention and allow safe planning in implantology. Four parasagittal sections of cone-beam computed tomography (CBCT) from 100 patients were bilaterally analyzed. Linear measurements of the submandibular fossa depth, bone height and thickness were performed. The submandibular fossa was also classified into non-influential undercuts and influential undercuts for implant placement. Mandibular canal corticalization was also evaluated and classified according to the visualization. Data on patient age and gender were also collected. Forty-one scans (41%) were from male patients, and 59 (59%) were from female patients. Patient age ranged between 18 and 84 years, with an average age of 51.37 years. The submandibular fossa depth and implant bone thickness had a significant effect on the variability of the sample (46.1% and 22.3%, respectively). The submandibular fossa depth was quite variable, and the highest values were observed in the posterior regions. In 18.27% of the cases, the presence of the fossa directly influenced implant placement, considering a bone height of 10mm (standard implant). A significant correlation was observed between fossa depth and bone thickness. Thus, greater attention should be paid to thick ridges; although thick ridges are favorable, they may be associated with deeper submandibular fossae. The mandibular canal was the most influential anatomical structure in the premolar region due to the reduced bone height in this region and the greater difficulty in viewing the canal, and the submandibular fossa was the most influential structure in the molar region due to lower bone height leading up to the fossa and the greater fossa depth in this region. Therefore, CBCT is an important tool for assessing the mandibular region

  10. Hydatidosis of the liver and posterior mediastinum

    OpenAIRE

    Quail, Jacob F; Gramins, Daniel L; Dutton, William D

    2015-01-01

    Introduction: Cystic echinococcus (CE) is an endemic zoonosis secondary to infection by the larval form of the cestode Echinococcus granulosus. An intermediate host, humans enter the organism’s life cycle by exposure to infected canid feces. The liver is the most common location of CE while mediastinal hydatid cysts are rarely reported. Presentation of case: We report a case of synchronous CE of the liver and posterior mediastinum treated sequentially using chemotherapy, percutaneous aspir...

  11. Posterior sternoclavicular dislocation: an American football injury

    DEFF Research Database (Denmark)

    Marker, L B; Klareskov, B

    1996-01-01

    Posterior dislocation of the sternoclavicular joint is uncommon, accounting for less than 0.1% of all dislocations. Since 1824 a little more than 100 cases have been reported, and the majority in the past 20 years. A review of published reports suggests that this injury is seen particularly in...... connection with American football. A typical case is described. The importance of this injury is that there is often a delay in diagnosis with potentially serious complications....

  12. Reversible posterior leukoencephalopathy after combination chemotherapy

    International Nuclear Information System (INIS)

    We describe a young woman with Burkitt's lymphoma, treated with intravenous adriamycine and cyclophosphamide and intrathecal cytarabine. She developed a reversible posterior leukoencephalopathy syndrome (RPLS) with typical MRI findings. Diffusion-weighted images during the first days after the onset of symptoms predicted a small irreversible lesion in the frontal lobe, verified on T2-weighted images 1 month later. The patient showed full recovery after high-dose steroid treatment. (orig.)

  13. Reversible posterior leukoencephalopathy after combination chemotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Honkaniemi, J.; Latvala, M.; Hietaharju, A.; Ollikainen, J.; Vaehaemaeki, L.; Frey, H. [Department of Neurology and Rehabilitation, Univ. of Tampere (Finland); Kaehaerae, V.; Dastidar, P. [Department of Radiology, Univ. of Tampere (Finland); Salonen, T. [Department of Internal Medicine, Univ. of Tampere (Finland); Keskinen, L.; Kellokumpu-Lehtinen, P. [Department of Oncology, Univ. of Tampere (Finland)

    2000-12-01

    We describe a young woman with Burkitt's lymphoma, treated with intravenous adriamycine and cyclophosphamide and intrathecal cytarabine. She developed a reversible posterior leukoencephalopathy syndrome (RPLS) with typical MRI findings. Diffusion-weighted images during the first days after the onset of symptoms predicted a small irreversible lesion in the frontal lobe, verified on T2-weighted images 1 month later. The patient showed full recovery after high-dose steroid treatment. (orig.)

  14. Cervical disc hernia operations through posterior laminoforaminotomy

    Directory of Open Access Journals (Sweden)

    Coskun Yolas

    2016-01-01

    Full Text Available Objective: The most common used technique for posterolateral cervical disc herniations is anterior approach. However, posterior cervical laminotoforaminomy can provide excellent results in appropriately selected patients with foraminal stenosis in either soft disc prolapse or cervical spondylosis. The purpose of this study was to present the clinical outcomes following posterior laminoforaminotomy in patients with radiculopathy. Materials and Methods: We retrospectively evaluated 35 patients diagnosed with posterolateral cervical disc herniation and cervical spondylosis with foraminal stenosis causing radiculopathy operated by the posterior cervical keyhole laminoforaminotomy between the years 2010 and 2015. Results: The file records and the radiographic images of the 35 patients were assessed retrospectively. The mean age was 46.4 years (range: 34-66 years. Of the patients, 19 were males and 16 were females. In all of the patients, the neurologic deficit observed was radiculopathy. The posterolaterally localized disc herniations and the osteophytic structures were on the left side in 18 cases and on the right in 17 cases. In 10 of the patients, the disc level was at C5-6, in 18 at C6-7, in 2 at C3-4, in 2 at C4-5, in 1 at C7-T1, in 1 patient at both C5-6 and C6-7, and in 1 at both C4-5 and C5-6. In 14 of these 35 patients, both osteophytic structures and protruded disc herniation were present. Intervertebral foramen stenosis was present in all of the patients with osteophytes. Postoperatively, in 31 patients the complaints were relieved completely and four patients had complaints of neck pain and paresthesia radiating to the arm (the success of operation was 88.5%. On control examinations, there was no finding of instability or cervical kyphosis. Conclusion: Posterior cervical laminoforaminotomy is an alternative appropriate choice in both cervical soft disc herniations and cervical stenosis.

  15. Confidence measures from local posterior probability estimates

    OpenAIRE

    Williams, Gethin; Renals, Steve

    1999-01-01

    In this paper we introduce a set of related confidence measures for large vocabulary continuous speech recognition (LVCSR) based on local phone posterior probability estimates output by an acceptor HMM acoustic model. In addition to their computational efficiency, these confidence measures are attractive as they may be applied at the state-, phone-, word- or utterance-levels, potentially enabling discrimination between different causes of low confidence recognizer output, such as unclear acou...

  16. Primary posterior perineal herniation of urinary bladder

    Directory of Open Access Journals (Sweden)

    Kurumboor Prakash

    2013-01-01

    Full Text Available Primary perineal hernia is a rare clinical condition wherein herniation of viscera occurs through pelvic diaphragm. They are usually mistaken for sciatic hernia, rectal prolapse or other diseases in the perineum. Correct identification of the type of hernia by imaging is crucial for planning treatment. We present a case of primary posterior herniation of urinary bladder and rectal wall through levator ani repaired laparoscopically using a mesh repair.

  17. Posterior moments computed by mixed integration

    OpenAIRE

    Dijk, Herman; Kloek, Teun; Boender, C.G.E.

    1985-01-01

    textabstractA flexible numerical integration method is proposed for the computation of moments of a multivariate posterior density with different tail properties in different directions. The method (called mixed integration) amounts to a combination of classical numerical integration and Monte Carlo integration. Mixed integration is parsimonious in the sense that is makes use of the same parameters as the more restrictive multivariate normal importance function. The method is applied in order...

  18. Posterior endoscopic discectomy (and other procedures)

    OpenAIRE

    M. Brayda-Bruno; Cinnella, P.

    2000-01-01

    Percutaneous approaches to lumbar discectomy were somewhat controversial, because of their limited indications. They have not proven to be as effective as standard open lumbar disc surgery, because of longer operating times and some technical problems in addressing all the different aspects of lumbar disc herniations. New percutaneous posterior procedures for lumbar disc disease have been described in the last few years, but the MicroEndoscopic Discectomy (MED) introduced by Foley and Smith i...

  19. Reversible Posterior Leukoencephalopathy Syndrome Induced by Pazopanib

    Directory of Open Access Journals (Sweden)

    Chelis Leonidas

    2012-10-01

    Full Text Available Abstract Background The reversible posterior leukoencephalopathy syndrome is a clinical/radiological syndrome characterized by headache, seizures, impaired vision, acute hypertension, and typical magnetic resonance imaging findings. There are several reports in the literature that depict its occurrence in cancer patients. The list of common anticancer and supportive care drugs that predispose to reversible posterior leukoencephalopathy syndrome is expanding and includes not only a large number of chemotherapeutic agents but also an increased number of new targeted drugs, particularly angiogenesis inhibitors such as bevacizumab,sorefenib and sunitinib. Pazopanib is an oral tyrosine kinase inhibitor targeting vascular endothelial growth factor receptor, platelet-derived growth factor receptor, and c-Kit which after a positive phase III randomized clinical trial in patients with advanced renal cell cancer received FDA approval for the treatment of advanced renal cell carcinoma. Until now no cases of reversible posterior leukoencephalopathy syndrome induced by pazopanib have been reported. Case report We present the case of a 40 years old female patient with heavily pre-treated metastatic renal cell carcinoma who received pazopanib as salvage treatment. After 21 days of pazopanib therapy the patient referred to the emergency department with epileptic seizure, impaired vision at both eyes and headache. MRI of the brain revealed subcortical oedema at the occipital and parietal lobes bilaterally. She was treated with anticonvulsants, i.v. administration of mannitol and antihypertensives and she recovered completely from her symptoms and was discharged on the tenth hospital day. A brain MRI performed 3 weeks after showed that the subcortical oedema had been subsided. Conclusion In conclusion this is the first case of pazopanib induced reversible posterior leukoencephalopathy syndrome. Although usually reversible, this syndrome is a serious and

  20. Cervical disc hernia operations through posterior laminoforaminotomy

    Science.gov (United States)

    Yolas, Coskun; Ozdemir, Nuriye Guzin; Okay, Hilmi Onder; Kanat, Ayhan; Senol, Mehmet; Atci, Ibrahim Burak; Yilmaz, Hakan; Coban, Mustafa Kemal; Yuksel, Mehmet Onur; Kahraman, Umit

    2016-01-01

    Objective: The most common used technique for posterolateral cervical disc herniations is anterior approach. However, posterior cervical laminotoforaminomy can provide excellent results in appropriately selected patients with foraminal stenosis in either soft disc prolapse or cervical spondylosis. The purpose of this study was to present the clinical outcomes following posterior laminoforaminotomy in patients with radiculopathy. Materials and Methods: We retrospectively evaluated 35 patients diagnosed with posterolateral cervical disc herniation and cervical spondylosis with foraminal stenosis causing radiculopathy operated by the posterior cervical keyhole laminoforaminotomy between the years 2010 and 2015. Results: The file records and the radiographic images of the 35 patients were assessed retrospectively. The mean age was 46.4 years (range: 34-66 years). Of the patients, 19 were males and 16 were females. In all of the patients, the neurologic deficit observed was radiculopathy. The posterolaterally localized disc herniations and the osteophytic structures were on the left side in 18 cases and on the right in 17 cases. In 10 of the patients, the disc level was at C5-6, in 18 at C6-7, in 2 at C3-4, in 2 at C4-5, in 1 at C7-T1, in 1 patient at both C5-6 and C6-7, and in 1 at both C4-5 and C5-6. In 14 of these 35 patients, both osteophytic structures and protruded disc herniation were present. Intervertebral foramen stenosis was present in all of the patients with osteophytes. Postoperatively, in 31 patients the complaints were relieved completely and four patients had complaints of neck pain and paresthesia radiating to the arm (the success of operation was 88.5%). On control examinations, there was no finding of instability or cervical kyphosis. Conclusion: Posterior cervical laminoforaminotomy is an alternative appropriate choice in both cervical soft disc herniations and cervical stenosis.

  1. Imaging the posterior mediastinum: a multimodality approach

    OpenAIRE

    Occhipinti, Mariaelena; Heidinger, Benedikt H.; Franquet, Elisa; Eisenberg, Ronald L.; Bankier, Alexander A.

    2015-01-01

    The posterior mediastinum contains several structures that can produce a wide variety of pathologic conditions. Descending thoracic aorta, esophagus, azygos and hemiazygos veins, thoracic duct, lymph nodes, adipose tissue, and nerves are all located in this anatomical region and can produce diverse abnormalities. Although chest radiography may detect many of these pathologic conditions, computed tomography and magnetic resonance are the imaging modalities of choice for further defining the re...

  2. Reversible Posterior Leukoencephalopathy Syndrome Induced by Pazopanib

    International Nuclear Information System (INIS)

    The reversible posterior leukoencephalopathy syndrome is a clinical/radiological syndrome characterized by headache, seizures, impaired vision, acute hypertension, and typical magnetic resonance imaging findings. There are several reports in the literature that depict its occurrence in cancer patients. The list of common anticancer and supportive care drugs that predispose to reversible posterior leukoencephalopathy syndrome is expanding and includes not only a large number of chemotherapeutic agents but also an increased number of new targeted drugs, particularly angiogenesis inhibitors such as bevacizumab,sorefenib and sunitinib. Pazopanib is an oral tyrosine kinase inhibitor targeting vascular endothelial growth factor receptor, platelet-derived growth factor receptor, and c-Kit which after a positive phase III randomized clinical trial in patients with advanced renal cell cancer received FDA approval for the treatment of advanced renal cell carcinoma. Until now no cases of reversible posterior leukoencephalopathy syndrome induced by pazopanib have been reported. We present the case of a 40 years old female patient with heavily pre-treated metastatic renal cell carcinoma who received pazopanib as salvage treatment. After 21 days of pazopanib therapy the patient referred to the emergency department with epileptic seizure, impaired vision at both eyes and headache. MRI of the brain revealed subcortical oedema at the occipital and parietal lobes bilaterally. She was treated with anticonvulsants, i.v. administration of mannitol and antihypertensives and she recovered completely from her symptoms and was discharged on the tenth hospital day. A brain MRI performed 3 weeks after showed that the subcortical oedema had been subsided. In conclusion this is the first case of pazopanib induced reversible posterior leukoencephalopathy syndrome. Although usually reversible, this syndrome is a serious and potentially life threatening adverse effect, if untreated, that should

  3. Vitamin D deficiency and posterior subcapsular cataract

    OpenAIRE

    Brown, Craig

    2015-01-01

    Craig J Brown,1 Faical Akaichi21The Eye Center, Fayetteville, AR, USA; 2Scotland’s Rural College, Edinburgh, UKPurpose: To evaluate risk factors associated with posterior subcapsular cataract (PSC) development and the relationship between vitamin D deficiency and etiology of PSC.Methods: Of 195 consecutive patients from a private ophthalmology practice, diagnosed with PSC, serum vitamin D3 (25-OH D) levels were obtained for 175, and associations among risk factors, comorbidities, an...

  4. Vitamin D deficiency and posterior subcapsular cataract

    OpenAIRE

    Brown CJ; Akaichi F

    2015-01-01

    Craig J Brown,1 Faical Akaichi21The Eye Center, Fayetteville, AR, USA; 2Scotland’s Rural College, Edinburgh, UKPurpose: To evaluate risk factors associated with posterior subcapsular cataract (PSC) development and the relationship between vitamin D deficiency and etiology of PSC.Methods: Of 195 consecutive patients from a private ophthalmology practice, diagnosed with PSC, serum vitamin D3 (25-OH D) levels were obtained for 175, and associations among risk factors, comorbidities, and PS...

  5. Posterior midline cervical fetal cystic hygroma.

    Directory of Open Access Journals (Sweden)

    Oak S

    1992-04-01

    Full Text Available Posterior midline cervical cystic hygromas (PMC are frequently found associated with chromosomal aberrations and usually do not survive. The present report illustrates diagnosis of this condition by sonography in an 18 weeks old fetus and an amniocentesis revealed 45 x0 karyotype and increased concentration of alpha-fetoproteins. Pregnancy was terminated in view of Turner′s syndrome. The etiology and natural history of the condition is reviewed.

  6. Bayesian Posterior Distributions Without Markov Chains

    OpenAIRE

    Cole, Stephen R.; Chu, Haitao; Greenland, Sander; Hamra, Ghassan; Richardson, David B.

    2012-01-01

    Bayesian posterior parameter distributions are often simulated using Markov chain Monte Carlo (MCMC) methods. However, MCMC methods are not always necessary and do not help the uninitiated understand Bayesian inference. As a bridge to understanding Bayesian inference, the authors illustrate a transparent rejection sampling method. In example 1, they illustrate rejection sampling using 36 cases and 198 controls from a case-control study (1976–1983) assessing the relation between residential ex...

  7. Coexistent ganglioglioma, focal cortical dysplasia, and hippocampal sclerosis (triple pathology) in chronic epilepsy.

    Science.gov (United States)

    Prayson, Richard A; Gales, Jordan M

    2015-10-01

    The most commonly identified pathologies in patients with medically intractable epilepsy include focal cortical dysplasia, hippocampal sclerosis, tumors, and remote ischemic damage. Surgery has proven to be an effective therapeutic modality in most of such patients. The coexistence of multiple pathologies in resected tissues is well documented, particularly ganglioglioma and focal cortical dysplasia. Cases of triple pathology are, however, extraordinarily unusual. We report 2 cases of triple pathology including hippocampal sclerosis, ganglioglioma, and focal cortical dysplasia. Cases of pathologically confirmed hippocampal sclerosis diagnosed between January 2000 to December 2012 (n= 349) were reviewed, and only 2 cases (0.6%) with triple pathology were identified. The histopathologic and clinical features of these 2 cases are reviewed. The patients included a 6-year-old girl and 10-year-old boy. The former patient presented with a 4-year history of epilepsy and oppositional defiant disorder. Imaging identified a lesion in the left parahippocampal gyrus and posterior hippocampus. The latter patient presented with an 8-year history of epilepsy, attention deficient hyperactivity disease, and a pervasive developmental disorder. Imaging identified a lesion in the left posterior temporal and occipital region. Resected tissues in both patients showed a ganglioglioma (World Health Organization grade I) with accompanying focal cortical dysplasia and hippocampal sclerosis. Both patients were seizure free on antiepileptic medication at last follow-up at 20 and 38 months, respectively. The prevalence of triple pathology including hippocampal sclerosis is low (<1% in the current study). Surgical intervention for triple pathology cases anecdotally appears effective in achieving seizure control. PMID:26235882

  8. Surgical approach for high-energy posterior tibial plateau fractures

    OpenAIRE

    Shu-Qing Wang; You-Shui Gao; Jia-Qi Wang; Chang-Qing Zhang; Jiong Mei; Zhi-Tao Rao

    2011-01-01

    Background: High-energy fractures of posterior tibial plateau always need surgical treatment. Generally, posterior fragments of these fractures could not be exposed and reduced well in conventional anterior approaches. Although a posterolateral/posteromedial approach to manage posterior tibial plateau fractures can achieve satisfactory results, there are few presentations concerning the treatment of these high-energy injuries based on posterior approaches combined with anterior approach if ne...

  9. MR imaging of posterior cruciate ligament injury

    International Nuclear Information System (INIS)

    There is increasing awareness of the clinical importance of early detection and treatment of posterior cruciate ligament(PCL) injury. We evaluate the usefulness of Magnetic resonance(MR) imaging in the diagnosis of PCL injury. We retrospectively analysed the MR images of 140 cases with clinically suspected knee injury. Arthroscopic or surgical correlation was available in 63 cases. We observed the finding and extent of PCL injury and other associated abnormalities. The frequency of anterior and posterior meniscofemoral ligament was evaluated. Eleven PCL injuries were observed, six midsubstance tears, two tibial attachment tears, two femoral attachment tear, one laxity. The sensitivity, specificity and accuracy of MR imaging diagnosis are 100%, 98.1%, 98.4%. MR findings of PCL injury are discontinuity and focal mass formation, irregular increased signal intensity, detachment or redundancy of the ligament with avulsed bony fragment. In all cases of injured PCL, other associated abnormalities of adjacent structures were observed. Accessory anterior and posterior meniscofemoral ligaments were observed in 67.4%(87/129). MR imaging is useful in evaluation of presence or absence of PCL injury, accurate extent of PCL injury and other important associated abnormalities of adjacent structures

  10. Towards a 'canonical' agranular cortical microcircuit

    Directory of Open Access Journals (Sweden)

    Sarah F. Beul

    2015-01-01

    Full Text Available Based on regularities in the intrinsic microcircuitry of cortical areas, variants of a 'canonical' cortical microcircuit have been proposed and widely adopted, particularly in computational neuroscience and neuroinformatics. However, this circuit is founded on striate cortex, which manifests perhaps the most extreme instance of cortical organization, in terms of a very high density of cells in highly differentiated cortical layers. Most other cortical regions have a less well differentiated architecture, stretching in gradients from the very dense eulaminate primary cortical areas to the other extreme of dysgranular and agranular areas of low density and poor laminar differentiation. It is unlikely for the patterns of inter- and intra-laminar connections to be uniform in spite of strong variations of their structural substrate. This assumption is corroborated by reports of divergence in intrinsic circuitry across the cortex. Consequently, it remains an important goal to define local microcircuits for a variety of cortical types, in particular, agranular cortical regions. As a counterpoint to the striate microcircuit, which may be anchored in an exceptional cytoarchitecture, we here outline a tentative microcircuit for agranular cortex. The circuit is based on a synthesis of the available literature on the local microcircuitry in agranular cortical areas of the rodent brain, investigated by anatomical and electrophysiological approaches. A central observation of these investigations is a weakening of interlaminar inhibition as cortical cytoarchitecture becomes less distinctive. Thus, our study of agranular microcircuitry revealed deviations from the well-known 'canonical' microcircuit established for striate cortex, suggesting variations in the intrinsic circuitry across the cortex that may be functionally relevant.

  11. Multisegmental cervical ossification of the posterior longitudinal ligament: Anterior vs posterior approach

    Directory of Open Access Journals (Sweden)

    Jain Subodh

    2005-01-01

    Full Text Available Aims : To determine the surgical approach in patients with multisegmental (four or more segments OPLL of the cervical spine. Methods and Materials : Data of 27 patients who had undergone either an anterior (corpectomy with excision of OPLL and interbody fusion=14 patients or posterior approach (laminectomy=12, laminoplasty=1 patient for the multisegmental cervical OPLL was analyzed retrospectively. The patients in each group were statistically similar in respect to preoperative factors such as age, duration of symptoms, preoperative modified Japanese orthopedic association score, OPLL thickness, effective canal diameter, and antero-posterior cord compression ratio. The clinical outcome was assessed by the Harsh grading system and recovery rate was assessed by Hirabayashi method. Results : There was no statistical difference in the outcome, and recovery rate. Nine patients developed complications after anterior approach in contrast to one after posterior approach. Conclusions : In patients with multisegmental cervical OPLL, there was no significant difference in the short-term recovery rate and outcome between two groups. The immediate postoperative complications were less in patients who had undergone posterior approach. From our analysis, it appears that the posterior approach is probably the preferred method of treatment in a multisegmental OPLL in absence of preoperative kyphosis.

  12. Effect of Posterior Femoral Condylar Offset and Posterior Tibial Slope on Maximal Flexion Angle of the Knee in Posterior Cruciate Ligament Sacrificing Total Knee Arthroplasty

    OpenAIRE

    Kim, Jong-Heon

    2013-01-01

    Purpose To evaluate the effect of femoral condylar offset and posterior tibial slope on maximal flexion angle of the knee in posterior cruciate ligament (PCL)-sacrificing total knee arthroplasty (TKA, Medial-Pivot Knee System). Materials and Methods Forty-five knees in 35 patients who could be followed up more than 1 year after PCL-sacrificing TKA were evaluated retrospectively. We measured and analyzed the preoperative and postoperative maximal flexion angle, posterior femoral condylar offse...

  13. Unsupervised fetal cortical surface parcellation

    Science.gov (United States)

    Dahdouh, Sonia; Limperopoulos, Catherine

    2016-03-01

    At the core of many neuro-imaging studies, atlas-based brain parcellations are used for example to study normal brain evolution across the lifespan. These atlases rely on the assumption that the same anatomical features are present on all subjects to be studied and that these features are stable enough to allow meaningful comparisons between different brain surfaces and structures These methods, however, often fail when applied to fetal MRI data, due to the lack of consistent anatomical features present across gestation. This paper presents a novel surface-based fetal cortical parcellation framework which attempts to circumvent the lack of consistent anatomical features by proposing a brain parcellation scheme that is based solely on learned geometrical features. A mesh signature incorporating both extrinsic and intrinsic geometrical features is proposed and used in a clustering scheme to define a parcellation of the fetal brain. This parcellation is then learned using a Random Forest (RF) based learning approach and then further refined in an alpha-expansion graph-cut scheme. Based on the votes obtained by the RF inference procedure, a probability map is computed and used as a data term in the graph-cut procedure. The smoothness term is defined by learning a transition matrix based on the dihedral angles of the faces. Qualitative and quantitative results on a cohort of both healthy and high-risk fetuses are presented. Both visual and quantitative assessments show good results demonstrating a reliable method for fetal brain data and the possibility of obtaining a parcellation of the fetal cortical surfaces using only geometrical features.

  14. Cortical spreading depression: An enigma

    Science.gov (United States)

    Miura, R. M.; Huang, H.; Wylie, J. J.

    2007-08-01

    The brain is a complex organ with active components composed largely of neurons, glial cells, and blood vessels. There exists an enormous experimental and theoretical literature on the mechanisms involved in the functioning of the brain, but we still do not have a good understanding of how it works on a gross mechanistic level. In general, the brain maintains a homeostatic state with relatively small ion concentration changes, the major ions being sodium, potassium, and chloride. Calcium ions are present in smaller quantities but still play an important role in many phenomena. Cortical spreading depression (CSD for short) was discovered over 60 years ago by A.A.P. Leão, a Brazilian physiologist doing his doctoral research on epilepsy at Harvard University, “Spreading depression of activity in the cerebral cortex," J. Neurophysiol., 7 (1944), pp. 359-390. Cortical spreading depression is characterized by massive changes in ionic concentrations and slow nonlinear chemical waves, with speeds on the order of mm/min, in the cortex of different brain structures in various experimental animals. In humans, CSD is associated with migraine with aura, where a light scintillation in the visual field propagates, then disappears, and is followed by a sustained headache. To date, CSD remains an enigma, and further detailed experimental and theoretical investigations are needed to develop a comprehensive picture of the diverse mechanisms involved in producing CSD. A number of mechanisms have been hypothesized to be important for CSD wave propagation. In this paper, we briefly describe several characteristics of CSD wave propagation, and examine some of the mechanisms that are believed to be important, including ion diffusion, membrane ionic currents, osmotic effects, spatial buffering, neurotransmitter substances, gap junctions, metabolic pumps, and synaptic connections. Continuum models of CSD, consisting of coupled nonlinear diffusion equations for the ion concentrations, and

  15. Functional connectivity-based parcellation and connectome of cortical midline structures in the mouse: a perfusion autoradiography study

    Directory of Open Access Journals (Sweden)

    Daniel P Holschneider

    2014-06-01

    Full Text Available Rodent cortical midline structures (CMS are involved in emotional, cognitive and attentional processes. Tract tracing has revealed complex patterns of structural connectivity demonstrating connectivity-based integration and segregation for the prelimbic, cingulate area 1, retrosplenial dysgranular cortices dorsally, and infralimbic, cingulate area 2, and retrosplenial granular cortices ventrally. Understanding of CMS functional connectivity (FC remains more limited. Here we present the first subregion-level FC analysis of the mouse CMS, and assess whether fear results in state-dependent FC changes analogous to what has been reported in humans. Brain mapping using [14C]-iodoantipyrine was performed in mice during auditory-cued fear conditioned recall and in controls. Regional cerebral blood flow was analyzed in 3-D images reconstructed from brain autoradiographs. Regions-of-interest were selected along the CMS anterior-posterior and dorsal-ventral axes. In controls, pairwise correlation and graph theoretical analyses showed strong FC within each CMS structure, strong FC along the dorsal-ventral axis, with segregation of anterior from posterior structures. Seed correlation showed FC of anterior regions to limbic/paralimbic areas, and FC of posterior regions to sensory areas--findings consistent with functional segregation noted in humans. Fear recall increased FC between the cingulate and retrosplenial cortices, but decreased FC between dorsal and ventral structures. In agreement with reports in humans, fear recall broadened FC of anterior structures to the amygdala and to somatosensory areas, suggesting integration and processing of both limbic and sensory information. Organizational principles learned from animal models at the mesoscopic level (brain regions and pathways will not only critically inform future work at the microscopic (single neurons and synapses level, but also have translational value to advance our understanding of human brain

  16. Multimodality Word-finding Distinctions in Cortical Stimulation Mapping

    Science.gov (United States)

    Serafini, Sandra; Clyde, Merlise; Tolson, Matt; Haglund, Michael M

    2015-01-01

    Background Cortical stimulation mapping (CSM) commonly uses visual naming to determine resection margins in the dominant hemisphere of epilepsy patients. Visual naming alone may not identify all language sites in resection-prone areas, prompting additional tasks for comprehensive language mapping. Objective To demonstrate word-finding distinctions between visual, auditory, and reading modalities during CSM and the percentage of modality-specific language sites within dominant hemisphere subregions. Methods Twenty-eight epilepsy patients underwent CSM using visual, auditory, and sentence completion tasks. Hierarchical logistic regression analyzed errors to identify language sites and provide modality-specific percentages within subregions. Results The percentage of sites classified as language sites based on auditory naming was twice as high in anterior temporal regions compared to visual naming, marginally higher in posterior temporal areas, and comparable in parietal regions. Sentence completion was comparable to visual and auditory naming in parietal regions, and lower in most temporal areas. Of 470 sites tested with both visual and auditory naming, 95 sites were distinctly auditory while 48 sites were distinctly visual. The remaining sites overlapped. Conclusion Distinct cortical areas were found for distinct input modalities, with language sites in anterior tip regions found most often using auditory naming. The vulnerability of anterior temporal tip regions to resection in this population and distinct sites for each modality suggest a multimodality approach may be needed to spare crucial language sites, if sparing those sites can be shown to significantly reduce the rate of post-operative language deficits without sacrificing seizure control. PMID:23615091

  17. Cervical ossification of the posterior longitudinal ligament: Anterior versus posterior approach

    Directory of Open Access Journals (Sweden)

    Dasheng Lin

    2012-01-01

    Full Text Available Background: The optimal approach to provide satisfactory decompression and minimize complications for ossification of the posterior longitudinal ligament (OPLL involving multiple levels (3 levels or more remains controversial. The purpose of this study was to compare the results of two surgical approaches for cervical OPLL involving multiple levels; anterior direct decompression and fixation, and posterior indirect decompression and fixation. We present a retrospective review of 56 cases followed at a single Institution. Materials and Methods: We compared patients of multiple levels cervical OPLL that were treated at a single institution either with anterior direct decompression and fixation or with posterior indirect decompression and fixation. The clinical records of the patients with a minimum duration of follow-up of 2 years were reviewed. The associated complications were recorded. Results: Fifty-six patients constitute the clinical material. 26 cases were treated by anterior corpectomy and fixation and 30 cases received posterior laminectomy and fixation. The two populations were similar. It was found that both anterior and posterior decompression and fixation can achieve satisfactory outcomes, and posterior surgery was accomplished in a shorter period of time with lesser blood loss. Although patients had comparable preoperative Japanese Orthopaedics Association (JOA scores, those with a canal occupancy by OPLL more than 50% and managed anteriorly had better outcomes. However, for those with more severe stenosis, anterior approach was more difficult and associated with higher risks and complications. Despite its limitations in patients with high occupancy OPLLs, through the multiple level laminectomy, posterior fixation can achieve effective decompression, maintaining or restoring stability of the cervical spine, and thereby improving neural outcome and preventing the progression of OPLL. Conclusions: The posterior indirect decompression

  18. SINDROME DE COLAPSO DE MORDIDA POSTERIOR

    Directory of Open Access Journals (Sweden)

    Paula Alejandra Baldión

    2012-12-01

    Full Text Available El Síndrome de Colapso de Mordida posterior es una patología oclusal que se presenta como consecuencia de problemas dentales, periodontales y oclusales, que exige la correcta evaluación de los signos y síntomas que lo caracterizan.  El objetivo del artículo es describir la manera como evoluciona la enfermedad, la evaluación multidisciplinaria para obtener un diagnóstico preciso y la secuencia de tratamiento integral, revisando los conceptos para un mejor entendimiento del tratamiento periodontal y restaurativo que requieren los pacientes con síndrome de colapso de mordida posterior; caracterizado por procesos patológicos como enfermedad periodontal, caries dental con subsecuente alteración de la integridad del arco dentario que genera perdida de soporte posterior conllevando a un trauma oclusal secundario y disminución de la dimensión vertical oclusal. El control del proceso inflamatorio y la estabilización periodontal son puntos de partida indispensables en el tratamiento integral del paciente. La migración patológica de los dientes y las alteraciones del plano oclusal pueden exigir la corrección ortodóntica de los arcos y en algunos casos el concurso de cirugía oral para la nivelación del plano oclusal. La secuencia organizada del tratamiento por fases permite la restauración predecible de los pacientes con este síndrome, tomando en cuenta las diferentes alternativas protésicas tanto removibles como fijas con o sin implantes de oseointegración, para el éxito integral a largo plazo.

  19. MRI of the fetal posterior fossa

    International Nuclear Information System (INIS)

    MRI is a useful tool to complement US for imaging of the fetal posterior fossa (PF). In France, the discovery of a PF malformation in the fetus frequently leads to termination of pregnancy (80% in a personal series). However, despite improved accuracy in the diagnosis of PF abnormalities, prognosis remains uncertain. The first objective of this review is to document the normal MRI landmarks of the developing fetal PF. Because of their thinness, the visibility of the cerebellar fissures is dramatically delayed on MRI compared to macroscopic data. An important landmark is identification of the primary fissure of the vermis, normally seen at around 25-26 weeks' gestation (WG) on the sagittal slice, separating the larger posterior lobe from the anterior lobe (volume ratio around 2:1). The prepyramidal and secondary fissures are usually only identifiable after 32 WG and the hemispheric fissures are difficult to see until the end of pregnancy. Considering the signal changes, high signal on T2-weighted (T2-W) sequences is seen from 25 WG in the posterior part of the brain stem (tegmentum and ascending sensory tracts) related to myelination. The low signal intensities seen within the cerebellum on T2-W images correspond to high cellularity of grey matter (deep nuclei), as there is no myelination within the white matter before 38 WG. The second objective is to highlight the signs highly predictive of a poor neurological prognosis. Lack of pontine curvature or vermian agenesis without a PF cyst (small volume of PF) is greatly associated with poor neurological status. The third objective is to propose a diagnostic strategy in difficult cases where prognosis is important, e.g. the Dandy Walker continuum. (orig.)

  20. Spatiotemporal SERT expression in cortical map development.

    Science.gov (United States)

    Chen, Xiaoning; Petit, Emilie I; Dobrenis, Kostantin; Sze, Ji Ying

    2016-09-01

    The cerebral cortex is organized into morphologically distinct areas that provide biological frameworks underlying perception, cognition, and behavior. Profiling mouse and human cortical transcriptomes have revealed temporal-specific differential gene expression modules in distinct neocortical areas during cortical map establishment. However, the biological roles of spatiotemporal gene expression in cortical patterning and how cortical topographic gene expression is regulated are largely unknown. Here, we characterize temporal- and spatial-defined expression of serotonin (5-HT) transporter (SERT) in glutamatergic neurons during sensory map development in mice. SERT is transiently expressed in glutamatergic thalamic neurons projecting to sensory cortices and in pyramidal neurons in the prefrontal cortex (PFC) and hippocampus (HPC) during the period that lays down the basic functional neural circuits. We previously identified that knockout of SERT in the thalamic neurons blocks 5-HT uptake by their thalamocortical axons, resulting in excessive 5-HT signaling that impairs sensory map architecture. In contrast, here we show that selective SERT knockout in the PFC and HPC neurons does not perturb sensory map patterning. These data suggest that transient SERT expression in specific glutamatergic neurons provides area-specific instructions for cortical map patterning. Hence, genetic and pharmacological manipulations of this SERT function could illuminate the fundamental genetic programming of cortex-specific maps and biological roles of temporal-specific cortical topographic gene expression in normal development and mental disorders. PMID:27282696

  1. Cortical feedback control of olfactory bulb circuits.

    Science.gov (United States)

    Boyd, Alison M; Sturgill, James F; Poo, Cindy; Isaacson, Jeffry S

    2012-12-20

    Olfactory cortex pyramidal cells integrate sensory input from olfactory bulb mitral and tufted (M/T) cells and project axons back to the bulb. However, the impact of cortical feedback projections on olfactory bulb circuits is unclear. Here, we selectively express channelrhodopsin-2 in olfactory cortex pyramidal cells and show that cortical feedback projections excite diverse populations of bulb interneurons. Activation of cortical fibers directly excites GABAergic granule cells, which in turn inhibit M/T cells. However, we show that cortical inputs preferentially target short axon cells that drive feedforward inhibition of granule cells. In vivo, activation of olfactory cortex that only weakly affects spontaneous M/T cell firing strongly gates odor-evoked M/T cell responses: cortical activity suppresses odor-evoked excitation and enhances odor-evoked inhibition. Together, these results indicate that although cortical projections have diverse actions on olfactory bulb microcircuits, the net effect of cortical feedback on M/T cells is an amplification of odor-evoked inhibition. PMID:23259951

  2. Posterior Reversible Encephalopathy Syndrome in Pediatric Hematologic- Oncologic Disease: Literature Review and Case Presentation

    Directory of Open Access Journals (Sweden)

    Mohammad Thaghi ARZANIAN

    2014-04-01

    Full Text Available How to Cite This Article: Arzanian MT, Shamsian BSh, Karimzadeh P, Kajiyazdi M, Malek F, Hammoud M. Posterior Reversible Encephalopathy Syndrome in Pediatric Hematologic-Oncologic Disease: Literature Review and Case Presentation. Iran J Child Neurol. 2014 Spring 8(2:1-10.ObjectivePosterior reversible encephalopathy syndrome (PRES is a cliniconeuroradiological disease entity, which is represented by characteristic magnetic resonance imaging (MRI findings of subcortical/cortical hyperintensity in T2-weighted sequences. It is more often seen in parietaloccipital lobes, and is accompanied by clinical neurological changes. PRES is a rare central nervous system (CNS complication in patients with childhood hematologic-oncologic disese and shows very different neurological symptoms between patients, ranging from numbness of extremities to generalized seizure.In this article, we will review PRES presentation in hematologic-oncologic patients. Then, we will present our patient, a 7-year-old boy with Evans syndrome on treatment with cyclosporine, mycophenolate mofetil (MMF and prednisone, with seizure episodes and MRI finding in favour of PRES. References1. De Laat P, Te Winkel ML, Devos AS, Catsman-Berrevoets CE, Pieters R, van den Heuvel-Eibrink MM. Posterior reversible encephalopathy syndrome in childhood cancer. Ann Oncol 2011;22(2:472-8.2. Siebert E, Spors B, Bohner G, Endres M, LimanTG. Posterior reversible encephalopathy syndrome in children: radiological and clinical findings - a retrospective analysis of a German tertiary care center. Eur J Paediatr Neurol 2013;17(2:169-75.3. Lucchini G, Grioni D, Colombini A, Contri M, De Grandi C, Rovelli A, et al. Encephalopathy Syndrome in Children With Hemato-Oncological Disorders Is Not Always Posterior and Reversible. Pediatr Blood Cancer 2008;51:629–33.4. Kim SJ, Im SA, Lee JW, Chung NG, Cho B, Kim HK. Predisposing Factors of Posterior Reversible Encephalopathy Syndrome in Acute Childhood

  3. A systematic approach to posterior fossa malformations

    International Nuclear Information System (INIS)

    Full text: Embryology of the cerebellum and classification of posterior fossa malformations: At the 28th-37th gestational day, the thin roof of the hindbrain (future fourth ventricle) is formed by an ependymal membrane coated by pia mater. The plica choroidea, a precursor of the future choroid plexus, divides the roof of the fourth ventricle into the anterior membranous area (AMA) lying cephalad, and the posterior membranous area (PMA) lying caudad. The cerebellum arises from dorsal rhombomere 1 of the anterior hindbrain, in a position along the anterior/posterior axis of the neural tube that is determined by genes expressing in the isthmic organizer at the mid-hindbrain junction, and is also influenced by genetic cues from the roof plate of the adjacent fourth ventricle. Studies in mice have shown that during early embryogenesis, the dorsal rhombomere 1 rotates to establish the mediolaterally-oriented bilateral cerebellar primordial, which are interposed by the AMA. As neurogenesis progresses, the bilateral primordia fuse on the dorsal midline over the fourth ventricle to establish the medial vermis and lateral cerebellar hemispheres, while the intervening AMA progressively involutes until its remnants are incorporated in the choroid plexus. Meanwhile, the PMA shows a transient posterior finger-like expansion, the Blake’s pouch, which extends below the vermis and eventually disappears as the foramen of Magendie opens. Cerebellar neurons are generated from two anatomically and molecularly distinct progenitor zones within the cerebellar primordium: the cerebellar ventricular zone (vZ), and the dorsally located rhombic lip (Rl). Newly differentiating neurons from the vZ, including cerebellar Purkinje cells, are postmitotic, and leave the vZ to migrate radially within the developing cerebellum; instead, cells exiting the Rl migrate over the primordium forming the external granule layer (eGl), where they proliferate and then migrate inward to form the internal

  4. Sindrome de colapso de mordida posterior

    OpenAIRE

    Paula Alejandra Baldión; Diego Enrique Betancourt Castro

    2012-01-01

    El Síndrome de Colapso de Mordida posterior es una patología oclusal que se presenta como consecuencia de problemas dentales, periodontales y oclusales, que exige la correcta evaluación de los signos y síntomas que lo caracterizan.  El objetivo del artículo es describir la manera como evoluciona la enfermedad, la evaluación multidisciplinaria para obtener un diagnóstico preciso y la secuencia de tratamiento integral, revisando los conceptos para un mejor entendimiento del tratamiento periodon...

  5. Converging posterior distributions in space debris monitoring

    International Nuclear Information System (INIS)

    Ground-based radars monitor the falling space debris in order to prevent collisions with spacecrafts and satellites. Experiments with European Incoherent Scatter (EISCAT) Scientific Association radars using new data acquisition equipment suitable for space debris detection have raised a question what happens to a Bayesian solution when the sampling frequency of the reflected signal is increased. Assuming slightly idealized measurements, we show that the posterior densities converge in this case. This shows that the sampling method suits well for the statistical inverse problem.

  6. Reversible Posterior Encephalopathy Syndrome Secondary to Sunitinib

    Directory of Open Access Journals (Sweden)

    Ricardo Costa

    2014-01-01

    Full Text Available Reversible posterior leukoencephalopathy syndrome (RPLS is clinical radiologic condition associated with neurological symptoms and cerebral white matter edema. It has been associated with uncontrolled hypertension, eclampsia, immunosuppressants, and more recently the use of antiangiogenic drugs. Sunitinib is an inhibitor of the vascular endothelial growth factor receptor widely used in the treatment of metastatic renal cell carcinoma (RCC. We report a rare case of RPLS occurring on therapy with sunitinib in a patient with RCC. Our aim is to highlight the importance of considering RPLS as a diagnostic possibility and to hold sunitinib for RCC patients presenting with neurologic symptoms.

  7. A Short History of Posterior Dynamic Stabilization

    Directory of Open Access Journals (Sweden)

    Cengiz Gomleksiz

    2012-01-01

    Full Text Available Interspinous spacers were developed to treat local deformities such as degenerative spondylolisthesis. To treat patients with chronic instability, posterior pedicle fixation and rod-based dynamic stabilization systems were developed as alternatives to fusion surgeries. Dynamic stabilization is the future of spinal surgery, and in the near future, we will be able to see the development of new devices and surgical techniques to stabilize the spine. It is important to follow the development of these technologies and to gain experience using them. In this paper, we review the literature and discuss the dynamic systems, both past and present, used in the market to treat lumbar degeneration.

  8. Posterior breast cancer: Mammographic and ultrasonographic features

    Directory of Open Access Journals (Sweden)

    Janković Ana

    2013-01-01

    Full Text Available Background/Aim. Posterior breast cancers are located in the prepectoral region of the breast. Owing to this distinctive anatomical localization, physical examination and mammographic or ultrasonographic evaluation can be difficult. The purpose of the study was to assess possibilities of diagnostic mammography and breast ultrasonography in detection and differentiation of posterior breast cancers. Methods. The study included 40 women with palpable, histopathological confirmed posterior breast cancer. Mammographic and ultrasonographic features were defined according to Breast Imaging Reporting and Data System (BI-RADS lexicon. Results. Based on standard two-view mammography 87.5%, of the cases were classified as BI-RADS 4 and 5 categories, while after additional mammographic views all the cases were defined as BIRADS 4 and 5 categories. Among 96 mammographic descriptors, the most frequent were: spiculated mass (24.0%, architectural distortion (16.7%, clustered microcalcifications (12.6% and focal asymmetric density (12.6%. The differentiation of the spiculated mass was significantly associated with the possibility to visualize the lesion at two-view mammography (p = 0.009, without the association with lesion diameter (p = 0.083 or histopathological type (p = 0.055. Mammographic signs of invasive lobular carcinoma were significantly different from other histopathological types (architectural distortion, p = 0.003; focal asymmetric density, p = 0.019; association of four or five subtle signs of malignancy, p = 0.006. All cancers were detectable by ultrasonography. Mass lesions were found in 82.0% of the cases. Among 153 ultrasonographic descriptors, the most frequent were: irregular mass (15.7%, lobulated mass (7.2%, abnormal color Doppler signals (20.3%, posterior acoustic attenuation (18.3%. Ultrasonographic BI-RADS 4 and 5 categories were defined in 72.5% of the cases, without a significant difference among various histopathological types (p = 0

  9. Asymptomatic posterior mediastinal teratoma diagnosed incidentally

    OpenAIRE

    Jaiswal, Riddhi; Rani, Poonam; Devenraj, Vijayant

    2014-01-01

    We present a young patient with occasional chest pain and an incidentally found posterior mediastinal mass on radiology which was confirmed as mature teratoma on histopathology. The gross specimen received in the department of pathology was globular measuring 9.0×7.0×5.5 cm and varying in consistency from soft cystic to firm. Cut surface showed numerous hair entangled in pultaceous material. Representative sections were taken and stained with H&E stain. Histopathology revealed haphazardly dis...

  10. Converging posterior distributions in space debris monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Lasanen, Sari [Department of Mathematical Sciences, University of Oulu, 90014 University of Oulu (Finland)], E-mail: sari.lasanen@oulu.fi

    2008-11-01

    Ground-based radars monitor the falling space debris in order to prevent collisions with spacecrafts and satellites. Experiments with European Incoherent Scatter (EISCAT) Scientific Association radars using new data acquisition equipment suitable for space debris detection have raised a question what happens to a Bayesian solution when the sampling frequency of the reflected signal is increased. Assuming slightly idealized measurements, we show that the posterior densities converge in this case. This shows that the sampling method suits well for the statistical inverse problem.

  11. Post-partum posterior reversible encephalopathy syndrome

    DEFF Research Database (Denmark)

    Aaen, Anne Albers; Jeppesen, Jørgen; Obaid, Hayder;

    2015-01-01

    Posterior reversible encephalopathy syndrome (PRES) is a complex clinical condition with vasogenic subcortical oedema caused by hypertension. Oedema is often seen on magnetic resonance imaging. The wide clinical spectrum ranges from headaches to vision loss and even death. Early diagnosis and...... treatment is important for the reversibility of the condition. In this case report we emphasize the importance of blood pressure control in a post-partum woman, who had a rather complicated pregnancy. The symptoms of PRES were not recognized immediately because of failure to use and acknowledge a blood...

  12. Encoding Cortical Dynamics in Sparse Features

    Directory of Open Access Journals (Sweden)

    Sheraz eKhan

    2014-05-01

    Full Text Available Distributed cortical solutions of magnetoencephalography (MEG and electroencephalography (EEG exhibit complex spatial and temporal dynamics. The extraction of patterns of interest and dynamic features from these cortical signals has so far relied on the expertise of investigators. There is a definite need in both clinical and neuroscience research for a method that will extract critical features from high-dimensional neuroimaging data in an automatic fashion. We have previously demonstrated the use of optical flow techniques for evaluating the kinematic properties of motion field projected on non-flat manifolds like in a cortical surface. We have further extended this framework to automatically detect features in the optical flow vector field by using the modified and extended 2-Riemannian Helmholtz Hodge Decomposition (HHD. Here, we applied these mathematical models on simulation and MEG data recorded from a healthy individual during a somatosensory experiment and an epilepsy pediatric patient during sleep. We tested whether our technique can automatically extract salient dynamical features of cortical activity. Simulation results indicated that we can precisely reproduce the simulated cortical dynamics with HHD; encode them in sparse features and represent the propagation of brain activity between distinct cortical areas. Using HHD, we decoded the somatosensory N20 component into two HHD features and represented the dynamics of brain activity as a traveling source between two primary somatosensory regions. In the epilepsy patient, we displayed the propagation of the epileptiform activity around the margins of a brain lesion. Our findings indicate that HHD measures computed from cortical dynamics can: (i quantitatively access the cortical dynamics in both healthy and disease brain in terms of sparse features and dynamic brain activity propagation between distinct cortical areas, and (ii facilitate a reproducible, automated analysis of MEG

  13. Cortical astrocytes rewire somatosensory cortical circuits for peripheral neuropathic pain.

    Science.gov (United States)

    Kim, Sun Kwang; Hayashi, Hideaki; Ishikawa, Tatsuya; Shibata, Keisuke; Shigetomi, Eiji; Shinozaki, Youichi; Inada, Hiroyuki; Roh, Seung Eon; Kim, Sang Jeong; Lee, Gihyun; Bae, Hyunsu; Moorhouse, Andrew J; Mikoshiba, Katsuhiko; Fukazawa, Yugo; Koizumi, Schuichi; Nabekura, Junichi

    2016-05-01

    Long-term treatments to ameliorate peripheral neuropathic pain that includes mechanical allodynia are limited. While glial activation and altered nociceptive transmission within the spinal cord are associated with the pathogenesis of mechanical allodynia, changes in cortical circuits also accompany peripheral nerve injury and may represent additional therapeutic targets. Dendritic spine plasticity in the S1 cortex appears within days following nerve injury; however, the underlying cellular mechanisms of this plasticity and whether it has a causal relationship to allodynia remain unsolved. Furthermore, it is not known whether glial activation occurs within the S1 cortex following injury or whether it contributes to this S1 synaptic plasticity. Using in vivo 2-photon imaging with genetic and pharmacological manipulations of murine models, we have shown that sciatic nerve ligation induces a re-emergence of immature metabotropic glutamate receptor 5 (mGluR5) signaling in S1 astroglia, which elicits spontaneous somatic Ca2+ transients, synaptogenic thrombospondin 1 (TSP-1) release, and synapse formation. This S1 astrocyte reactivation was evident only during the first week after injury and correlated with the temporal changes in S1 extracellular glutamate levels and dendritic spine turnover. Blocking the astrocytic mGluR5-signaling pathway suppressed mechanical allodynia, while activating this pathway in the absence of any peripheral injury induced long-lasting (>1 month) allodynia. We conclude that reawakened astrocytes are a key trigger for S1 circuit rewiring and that this contributes to neuropathic mechanical allodynia. PMID:27064281

  14. Tibial cortical lesions: A multimodality pictorial review

    Energy Technology Data Exchange (ETDEWEB)

    Tyler, P.A., E-mail: philippa.tyler@rnoh.nhs.uk [Department of Radiology, Royal National Orthopaedic Hospital, Brockley Hill, Stanmore HA7 4LP (United Kingdom); Mohaghegh, P., E-mail: pegah1000@gmail.com [Department of Radiology, Royal National Orthopaedic Hospital, Brockley Hill, Stanmore HA7 4LP (United Kingdom); Foley, J., E-mail: jfoley1@nhs.net [Department of Radiology, Glasgow Royal Infirmary, 16 Alexandra Parade, Glasgow G31 2ES (United Kingdom); Isaac, A., E-mail: amandaisaac@doctors.org.uk [Department of Radiology, King' s College Hospital, Denmark Hill, London SE5 9RS (United Kingdom); Zavareh, A., E-mail: ali.zavareh@gmail.com [Department of Radiology, North Bristol NHS Trust, Frenchay, Bristol BS16 1LE (United Kingdom); Thorning, C., E-mail: cthorning@doctors.org.uk [Department of Radiology, East Surrey Hospital, Canada Avenue, Redhill, Surrey RH1 5RH (United Kingdom); Kirwadi, A., E-mail: anandkirwadi@gmail.com [Department of Radiology, Manchester Royal Infirmary, Oxford Road, Manchester M13 9WL (United Kingdom); Pressney, I., E-mail: ipressney@hotmail.com [Department of Radiology, Royal National Orthopaedic Hospital, Brockley Hill, Stanmore HA7 4LP (United Kingdom); Amary, F., E-mail: fernanda.amary@rnoh.nhs.uk [Department of Histopathology, Royal National Orthopaedic Hospital, Brockley Hill, Stanmore HA7 4LP (United Kingdom); Rajeswaran, G., E-mail: grajeswaran@gmail.com [Department of Radiology, Chelsea and Westminster Hospital, 369 Fulham Road, London SW10 9NH (United Kingdom)

    2015-01-15

    Highlights: • Multimodality imaging plays an important role in the investigation and diagnosis of shin pain. • We review the multimodality imaging findings of common cortically based tibial lesions. • We also describe the rarer pathologies of tibial cortical lesions. - Abstract: Shin pain is a common complaint, particularly in young and active patients, with a wide range of potential diagnoses and resulting implications. We review the natural history and multimodality imaging findings of the more common causes of cortically-based tibial lesions, as well as the rarer pathologies less frequently encountered in a general radiology department.

  15. Tibial cortical lesions: A multimodality pictorial review

    International Nuclear Information System (INIS)

    Highlights: • Multimodality imaging plays an important role in the investigation and diagnosis of shin pain. • We review the multimodality imaging findings of common cortically based tibial lesions. • We also describe the rarer pathologies of tibial cortical lesions. - Abstract: Shin pain is a common complaint, particularly in young and active patients, with a wide range of potential diagnoses and resulting implications. We review the natural history and multimodality imaging findings of the more common causes of cortically-based tibial lesions, as well as the rarer pathologies less frequently encountered in a general radiology department

  16. Linear and Curvilinear Trajectories of Cortical Loss with Advancing Age and Disease Duration in Parkinson's Disease.

    Science.gov (United States)

    Claassen, Daniel O; Dobolyi, David G; Isaacs, David A; Roman, Olivia C; Herb, Joshua; Wylie, Scott A; Neimat, Joseph S; Donahue, Manus J; Hedera, Peter; Zald, David H; Landman, Bennett A; Bowman, Aaron B; Dawant, Benoit M; Rane, Swati

    2016-05-01

    Advancing age and disease duration both contribute to cortical thinning in Parkinson's disease (PD), but the pathological interactions between them are poorly described. This study aims to distinguish patterns of cortical decline determined by advancing age and disease duration in PD. A convenience cohort of 177 consecutive PD patients, identified at the Vanderbilt University Movement Disorders Clinic as part of a clinical evaluation for Deep Brain Stimulation (age: M= 62.0, SD 9.3), completed a standardized clinical assessment, along with structural brain Magnetic Resonance Imaging scan. Age and gender matched controls (n=53) were obtained from the Alzheimer Disease Neuroimaging Initiative and Progressive Parkinson's Marker Initiative (age: M= 63.4, SD 12.2). Estimated changes in cortical thickness were modeled with advancing age, disease duration, and their interaction. The best-fitting model, linear or curvilinear (2(nd), or 3(rd) order natural spline), was defined using the minimum Akaike Information Criterion, and illustrated on a 3-dimensional brain. Three curvilinear patterns of cortical thinning were identified: early decline, late decline, and early-stable-late. In contrast to healthy controls, the best-fit model for age related changes in PD is curvilinear (early decline), particularly in frontal and precuneus regions. With advancing disease duration, a curvilinear model depicts accelerating decline in the occipital cortex. A significant interaction between advancing age and disease duration is evident in frontal, motor, and posterior parietal areas. Study results support the hypothesis that advancing age and disease duration differentially affect regional cortical thickness and display regional dependent linear and curvilinear patterns of thinning. PMID:27330836

  17. Grey matter volumetric changes related to recovery from hand paresis after cortical sensorimotor stroke.

    Science.gov (United States)

    Abela, E; Seiler, A; Missimer, J H; Federspiel, A; Hess, C W; Sturzenegger, M; Weder, B J; Wiest, R

    2015-09-01

    Preclinical studies using animal models have shown that grey matter plasticity in both perilesional and distant neural networks contributes to behavioural recovery of sensorimotor functions after ischaemic cortical stroke. Whether such morphological changes can be detected after human cortical stroke is not yet known, but this would be essential to better understand post-stroke brain architecture and its impact on recovery. Using serial behavioural and high-resolution magnetic resonance imaging (MRI) measurements, we tracked recovery of dexterous hand function in 28 patients with ischaemic stroke involving the primary sensorimotor cortices. We were able to classify three recovery subgroups (fast, slow, and poor) using response feature analysis of individual recovery curves. To detect areas with significant longitudinal grey matter volume (GMV) change, we performed tensor-based morphometry of MRI data acquired in the subacute phase, i.e. after the stage compromised by acute oedema and inflammation. We found significant GMV expansion in the perilesional premotor cortex, ipsilesional mediodorsal thalamus, and caudate nucleus, and GMV contraction in the contralesional cerebellum. According to an interaction model, patients with fast recovery had more perilesional than subcortical expansion, whereas the contrary was true for patients with impaired recovery. Also, there were significant voxel-wise correlations between motor performance and ipsilesional GMV contraction in the posterior parietal lobes and expansion in dorsolateral prefrontal cortex. In sum, perilesional GMV expansion is associated with successful recovery after cortical stroke, possibly reflecting the restructuring of local cortical networks. Distant changes within the prefrontal-striato-thalamic network are related to impaired recovery, probably indicating higher demands on cognitive control of motor behaviour. PMID:24906703

  18. Hydatidosis of the liver and posterior mediastinum

    Science.gov (United States)

    Quail, Jacob F; Gramins, Daniel L; Dutton, William D

    2014-01-01

    Introduction Cystic echinococcus (CE) is an endemic zoonosis secondary to infection by the larval form of the cestode Echinococcus granulosus. An intermediate host, humans enter the organism’s life cycle by exposure to infected canid feces. The liver is the most common location of CE while mediastinal hydatid cysts are rarely reported. Presentation of case We report a case of synchronous CE of the liver and posterior mediastinum treated sequentially using chemotherapy, percutaneous aspiration with injection of a scolicidal agent and re-aspiration (PAIR) and then staged minimally-invasive surgeries. Discussion Synchronous CE involving the liver and posterior mediastinum is rare. The treatment of hydatid liver and mediastinal disease is multimodal including chemotherapy, percutaneous and laparoscopic or open surgical interventions. One option for controlled puncture of hepatic and mediastinal CE includes PAIR followed by surgery. Conclusion The sequential use of chemotherapy and PAIR followed by surgery provides another treatment strategy for management of CE. We believe this strategy may be used safely in locations without endemic CE, including most regions of the United States. PMID:25562598

  19. Kashima's Posterior cordectomy using coablator our experience

    Directory of Open Access Journals (Sweden)

    Balasubramanian Thiagarajan

    2014-03-01

    Full Text Available Aim: To study the effectiveness of coblation technology in performing Kashima's procedure for bilateral abductor vocal fold paralysis. Methodology: Managing patients with bilateral vocal fold abductor paralysis is rather tricky one. It calls for delicate balance between airway and phonation. Various endolaryngeal techniques have been used to manage this problem. Here the authors describe their experience with posterior cordectomy using coablator. This study includes 10 patients who presented with stridor following bilateral abductor paralysis. All our patients were on tracheostomy tubes. They were very anxious with the tube and wanted decannulation done. All of these patients were operated by the same senior surgeon. These patients were managed with posterior cordotomy using coablation. Laryngeal wands were used in all these patients. These patients underwent spiggoting of their tracheostomy tube on the first post operative day. Decannulation was completed on the third post operative day. Early decannulation was made possible because there was negligible soft tissue oedema as these patients underwent coblation procedure. Observation: On discharge all of them had a good voice and adequate airway. These patients were able to climb two flights of stairs without discomfort.Although the causes of bilateral abductor paralysis of vocal cords are multifactorial post traumatic paralysis formed a large majority of our patients ( 8 who developed bilateral vocal fold paralysis following total thyroidectomy.

  20. Posterior fossa involvement in a recurrent gliosarcoma

    Directory of Open Access Journals (Sweden)

    Srikant Balasubramaniam

    2012-01-01

    Full Text Available Gliosarcoma (GSM is a WHO grade 4 tumor and a variant of glioblastoma multiforme with predilection for the temporal lobe. We record, perhaps the first case in literature, of a temporal lobe GSM with recurrence involving the posterior fossa. A 50-year-old man presented to us with headache, vomiting, and lethargy of relatively recent onset. Magnetic resonance imaging revealed a well-circumscribed lesion in the left temporal lobe for which left temporal craniotomy with radical excision of the tumor was performed. Histopathology was suggestive of GSM. He presented to us within a month of the first surgery with a large recurrence involving the temporal lobe. He underwent a second surgery with radical excision of the tumor. Histopathology was confirmatory of GSM. He was administered concomitant chemotherapy and radiotherapy. Within a fortnight of starting adjuvant therapy, the bone flap started bulging and a repeat computed tomography scan revealed a large recurrence extending into the posterior fossa. The patient′s relatives refused consent for third surgery and he finally succumbed on postoperative day 21. GSMs are aggressive tumors that have a temporal lobe predilection, but they may present anywhere in the brain. Detailed studies on larger cohort of cases are needed to understand the true nature of these biphasic tumors.

  1. Pseudoexfoliation material on posterior chamber intraocular lenses

    Directory of Open Access Journals (Sweden)

    Rocha-Bastos RA

    2014-08-01

    Full Text Available Ricardo António da Rocha-Bastos,1 Sérgio Estrela Silva,1 Flávio Prézia,1 Fernando Falcão-Reis,1,2 António B Melo11Department of Ophthalmology, Hospital São João, Alameda Prof Hernâni Monteiro, Porto, Portugal; 2Department of Sense Organs, Faculty of Medicine, University of Porto, Alameda Prof Hernâni Monteiro, Porto, PortugalAbstract: The presence of pseudoexfoliation material on the surface of an intraocular lens (IOL is a rare finding. We report a series of seven cases with different patterns of pseudoexfoliation material deposition on the posterior chamber IOLs, recognized 2–20 years after cataract surgery. Six patients had an IOL implanted in the capsular bag and one in the ciliary sulcus. Two patients had undergone posterior capsulotomy. Although the pathophysiological mechanisms and clinical significance of this finding remain unknown, the careful follow-up of pseudophakic patients with known or suspected pseudoexfoliation syndrome is essential to monitor the development or progression of glaucoma, since deposition of pseudoexfoliation material continues even after cataract surgery.Keywords: intraocular lens, glaucoma, exfoliation syndrome, cataract

  2. Posterior repair with perforated porcine dermal graft

    Directory of Open Access Journals (Sweden)

    G. Bernard Taylor

    2008-02-01

    Full Text Available OBJECTIVE: To compare postoperative vaginal incision separation and healing in patients undergoing posterior repair with perforated porcine dermal grafts with those that received grafts without perforations. Secondarily, the tensile properties of the perforated and non-perforated grafts were measured and compared. MATERIALS AND METHODS: This was a non-randomized retrospective cohort analysis of women with stage II or greater rectoceles who underwent posterior repair with perforated and non-perforated porcine dermal grafts (PelvicolTM CR Bard Covington, GA USA. The incidence of postoperative vaginal incision separation (dehiscence was compared. A secondary analysis to assess graft tensile strength, suture pull out strength, and flexibility after perforation was performed using standard test method TM 0133 and ASTM bending and resistance protocols. RESULTS: Seventeen percent of patients (21/127 who received grafts without perforations developed vaginal incision dehiscence compared to 7% (5/71 of patients who received perforated grafts (p = 0.078. Four patients with vaginal incision dehiscence with non-perforated grafts required surgical revision to facilitate healing. Neither tensile strength or suture pull out strength were significantly different between perforated and non-perforated grafts (p = 0.81, p = 0.29, respectively. There was no difference in the flexibility of the two grafts (p = 0.20. CONCLUSION: Perforated porcine dermal grafts retain their tensile properties and are associated with fewer vaginal incision dehiscences.

  3. Acute Spontaneous Posterior Fossa Subdural Hematoma

    Directory of Open Access Journals (Sweden)

    Osama Shukir Muhammed Amin

    2014-02-01

    Full Text Available Acute posterior fossa subdural hematomas are rare and most of them are trauma-related. Non-traumatic ones have been reported in patients who had idiopathic thrombocytopenic purpura or those who had been receiving anticoagulant therapy. We report on the case of 57-year-old Iranian man who developed sudden severe occipital headache, drowsiness, repeated vomiting, and instability of stance and gait. He was neither hypertensive nor diabetic. No history of head trauma was obtained and he denied illicit drug or alcohol ingestion. A preliminary diagnosis of acute intra-cerebellar hemorrhage was made. His CT brain scan revealed an acute right-sided, extra-axial, crescent-shaped hyperdense area at the posterior fossa. His routine blood tests, platelets count, bleeding time, and coagulation profile were unremarkable. The patient had spontaneous acute infratentorial subdural hematoma. He was treated conservatively and discharged home well after 5 days. Since then, we could not follow-up him, clinically and radiologically because he went back to Iran. Our patient’s presentation, clinical course, and imaging study have called for conservative management, as the overall presentation was relatively benign. Unless the diagnosis is entertained and the CT brain scan is well-interpreted, the diagnosis may easily escape detection.

  4. Structural alteration of the dorsal visual network in DLB patients with visual hallucinations: a cortical thickness MRI study.

    Directory of Open Access Journals (Sweden)

    Stefano Delli Pizzi

    Full Text Available Visual hallucinations (VH represent one of the core features in discriminating dementia with Lewy bodies (DLB from Alzheimer's Disease (AD. Previous studies reported that in DLB patients functional alterations of the parieto-occipital regions were correlated with the presence of VH. The aim of our study was to assess whether morphological changes in specific cortical regions of DLB could be related to the presence and severity of VH. We performed a cortical thickness analysis on magnetic resonance imaging data in a cohort including 18 DLB patients, 15 AD patients and 14 healthy control subjects. Relatively to DLB group, correlation analysis between the cortical thickness and the Neuropsychiatric Inventory (NPI hallucination item scores was also performed. Cortical thickness was reduced bilaterally in DLB compared to controls in the pericalcarine and lingual gyri, cuneus, precuneus, superior parietal gyrus. Cortical thinning was found bilaterally in AD compared to controls in temporal cortex including the superior and middle temporal gyrus, part of inferior temporal cortex, temporal pole and insula. Inferior parietal and supramarginal gyri were also affected bilaterally in AD as compared to controls. The comparison between DLB and AD evidenced cortical thinning in DLB group in the right posterior regions including superior parietal gyrus, precuneus, cuneus, pericalcarine and lingual gyri. Furthermore, the correlation analysis between cortical thickness and NPI hallucination item scores showed that the structural alteration in the dorsal visual regions including superior parietal gyrus and precuneus closely correlated with the occurrence and severity of VH. We suggest that structural changes in key regions of the dorsal visual network may play a crucial role in the physiopathology of VH in DLB patients.

  5. Automatic domain-general processing of sound source identity in the left posterior middle frontal gyrus.

    Science.gov (United States)

    Giordano, Bruno L; Pernet, Cyril; Charest, Ian; Belizaire, Guylaine; Zatorre, Robert J; Belin, Pascal

    2014-09-01

    Identifying sound sources is fundamental to developing a stable representation of the environment in the face of variable auditory information. The cortical processes underlying this ability have received little attention. In two fMRI experiments, we investigated passive adaptation to (Exp. 1) and explicit discrimination of (Exp. 2) source identities for different categories of auditory objects (voices, musical instruments, environmental sounds). All cortical effects of source identity were independent of high-level category information, and were accounted for by sound-to-sound differences in low-level structure (e.g., loudness). A conjunction analysis revealed that the left posterior middle frontal gyrus (pMFG) adapted to identity repetitions during both passive listening and active discrimination tasks. These results indicate that the comparison of sound source identities in a stream of auditory stimulation recruits the pMFG in a domain-general way, i.e., independent of the sound category, based on information contained in the low-level acoustical structure. pMFG recruitment during both passive listening and explicit identity comparison tasks also suggests its automatic engagement in sound source identity processing. PMID:25038309

  6. Posterior Reversible Encephalopathy Syndrome in Two Omani Children with Underlying Renal Diseases

    Directory of Open Access Journals (Sweden)

    Mohamed A. El-Naggari

    2015-08-01

    Full Text Available Posterior reversible encephalopathy syndrome (PRES is a neurological condition with a combination of clinical and radiological features. Clinical symptoms include headaches, confusion, seizures, disturbed vision or an altered level of consciousness. Classic magnetic resonance imaging (MRI findings indicate subcortical and cortical oedema, affecting mainly the posterior cerebral region. We report two paediatric cases of PRES with underlying renal diseases presenting at the Sultan Qaboos University Hospital in Muscat, Oman, in April 2010 and August 2011. The first case was an 11-year-old girl diagnosed with systemic lupus erythematosus and the second was a six-and-a-half-year-old boy on peritoneal dialysis due to multi-drug-resistant nephrotic syndrome. Both patients were hypertensive and treated with blood pressure control medications. No residual neurological dysfunction was noted in the patients at a one-year follow-up and at discharge, respectively. The role of hypertension in paediatric PRES cases, among other important risk factors, is emphasised. Additionally, MRI is an important diagnostic and prognostic tool. Prompt diagnosis and aggressive management is fundamental to preventing permanent neurological damage.

  7. The Diversity of Cortical Inhibitory Synapses

    Directory of Open Access Journals (Sweden)

    Yoshiyuki eKubota

    2016-04-01

    Full Text Available The most typical and well known inhibitory action in the cortical microcircuit is a strong inhibition on the target neuron by axo-somatic synapses. However, it has become clear that synaptic inhibition in the cortex is much more diverse and complicated. Firstly, at least ten or more inhibitory non-pyramidal cell subtypes engage in diverse inhibitory functions to produce the elaborate activity characteristic of the different cortical states. Each distinct non-pyramidal cell subtype has its own independent inhibitory function. Secondly, the inhibitory synapses innervate different neuronal domains, such as axons, spines, dendrites and soma, and their IPSP size is not uniform. Thus cortical inhibition is highly complex, with a wide variety of anatomical and physiological modes. Moreover, the functional significance of the various inhibitory synapse innervation styles and their unique structural dynamic behaviors differ from those of excitatory synapses. In this review, we summarize our current understanding of the inhibitory mechanisms of the cortical microcircuit.

  8. Cortical high-density counterstream architectures.

    Science.gov (United States)

    Markov, Nikola T; Ercsey-Ravasz, Mária; Van Essen, David C; Knoblauch, Kenneth; Toroczkai, Zoltán; Kennedy, Henry

    2013-11-01

    Small-world networks provide an appealing description of cortical architecture owing to their capacity for integration and segregation combined with an economy of connectivity. Previous reports of low-density interareal graphs and apparent small-world properties are challenged by data that reveal high-density cortical graphs in which economy of connections is achieved by weight heterogeneity and distance-weight correlations. These properties define a model that predicts many binary and weighted features of the cortical network including a core-periphery, a typical feature of self-organizing information processing systems. Feedback and feedforward pathways between areas exhibit a dual counterstream organization, and their integration into local circuits constrains cortical computation. Here, we propose a bow-tie representation of interareal architecture derived from the hierarchical laminar weights of pathways between the high-efficiency dense core and periphery. PMID:24179228

  9. Response of cortical bone to antiresorptive treatment

    DEFF Research Database (Denmark)

    Hyldstrup, Lars; Jørgensen, J T; Sørensen, T K; Baeksgaard, L

    2001-01-01

    A total of 113 postmenopausal women (69 controls, 33 using hormone replacement therapy (HRT), and 11 using bisphosphonate) were evaluated twice over 2 years with a new noninvasive, radiogrammetry-based technique called digital X-ray radiogrammetry (DXR) and conventional bone densitometry of the...... spine, hip, and forearm. Longitudinal changes in bone densitometry were compared with changes captured by DXR: BMD evaluated by DXR (BMDDXR), cortical thickness of the second metacarpal (CTMC2), and porosity of cortical bone. The expected annual postmenopausal reduction in BMD in the control group was...... the bisphosphonate group, cortical porosity was significantly reduced (P < 0.025). Comparing longitudinal changes in age-matched subsamples of controls and bisphosphonate treated, BMDDXR, CTMC2, and porosity of cortical bone all differed significantly (P < 0.01, P < 0.05, P < 0.05, respectively...

  10. Neurological, neuropsychological and neuroradiological studies of the posterior cerebral artery occlusion

    International Nuclear Information System (INIS)

    Neurological, neuropsychological and neuroradiological studies were performed on 31 cases of the posterior cerebral artery (PCA) occlusion diagnosed by cerebral angiography and/or computed tomography (CT). Neurological examinations revealed visual field defect in 28 cases, contralateral sensory disturbance and hemiparesis in 23 cases and mental syndrome of memory disturbance, disorientation or confusion in 8 cases. CT was done on 17 cases out of 23 cases with contralateral sensory disturbance and hemiparesis. Ten cases of them revealed to have thalamic lesions by CT. In 7 cases which had no evidence of thalamic lesion by CT, 3 cases were highly suspected to have thalamic involvement clinically. The neurological and neuroradiological findings revealed high incidence and its pathomechanism of thalamic lesion in the cases of PCA occlusion. Neuropsychological examinations disclosed pure alexia in 6 cases, cortical blindness in 2 cases and hemispatial agnosia in 2 cases. Four cases with pure alexia were followed their alexic symptoms. Alexic symptoms lasted long in 3 cases. In these cases, collateral flow to the territory of the occlude PCA was hardly visible. One case with a relatively good collateral filling of the occluded PCA, alexic symptoms showed gradual improvement. Two cases with cortical blindness were proven to have bilateral PCA occlusion. In these 2 cases, collateral filling was hardly visible and their symptoms were permanent. The neurological and neuroradiological findings mentioned above suggest that the prognosis of pure alexia and cortical blindness depends largely on the degree of development of collateral circulation to the occluded PCA. Hemispatial agnosia was seen in 2 cases. (author)

  11. Frontal-posterior theta oscillations reflect memory retrieval during sentence comprehension.

    Science.gov (United States)

    Meyer, Lars; Grigutsch, Maren; Schmuck, Noura; Gaston, Phoebe; Friederici, Angela D

    2015-10-01

    Successful working-memory retrieval requires that items be retained as distinct units. At the neural level, it has been shown that theta-band oscillatory power increases with the number of to-be-distinguished items during working-memory retrieval. Here we hypothesized that during sentence comprehension, verbal-working-memory retrieval demands lead to increased theta power over frontal cortex, supposedly supporting the distinction amongst stored items during verbal-working-memory retrieval. Also, synchronicity may increase between the frontal cortex and the posterior cortex, with the latter supposedly supporting item retention. We operationalized retrieval by using pronouns, which refer to and trigger the retrieval of antecedent nouns from a preceding sentence part. Retrieval demand was systematically varied by changing the pronoun antecedent: Either, it was non-embedded in the preceding main clause, and thus easy-to-retrieve across a single clause boundary, or embedded in the preceding subordinate clause, and thus hard-to-retrieve across a double clause boundary. We combined electroencephalography (EEG), scalp-level time-frequency analysis, source localization, and source-level coherence analysis, observing a frontal-midline and broad left-hemispheric theta-power increase for embedded-antecedent compared to non-embedded-antecedent retrieval. Sources were localized to left-frontal, left-parietal, and bilateral-inferior-temporal cortices. Coherence analyses suggested synchronicity between left-frontal and left-parietal and between left-frontal and right-inferior-temporal cortices. Activity of an array of left-frontal, left-parietal, and bilateral-inferior-temporal cortices may thus assist retrieval during sentence comprehension, potentially indexing the orchestration of item distinction, verbal working memory, and long-term memory. Our results extend prior findings by mapping prior knowledge on the functional role of theta oscillations onto processes genuine to human

  12. Study of prognostic significance of antenatal ultrasonography and renin angiotensin system activation in predicting disease severity in posterior urethral valves

    Directory of Open Access Journals (Sweden)

    Divya Bhadoo

    2015-01-01

    Full Text Available Aims: Study on prognostic significance of antenatal ultrasonography and renin angiotensin system activation in predicting disease severity in posterior urethral valves. Materials and Methods: Antenatally diagnosed hydronephrosis patients were included. Postnatally, they were divided into two groups, posterior urethral valve (PUV and non-PUV. The studied parameters were: Gestational age at detection, surgical intervention, ultrasound findings, cord blood and follow up plasma renin activity (PRA values, vesico-ureteric reflux (VUR, renal scars, and glomerular filtration rate (GFR. Results: A total of 25 patients were included, 10 PUV and 15 non-PUV. All infants with PUV underwent primary valve incision. GFR was less than 60 ml/min/1.73 m 2 body surface area in 4 patients at last follow-up. Keyhole sign, oligoamnios, absent bladder cycling, and cortical cysts were not consistent findings on antenatal ultrasound in PUV. Cord blood PRA was significantly higher (P < 0.0001 in PUV compared to non-PUV patients. Gestational age at detection of hydronephrosis, cortical cysts, bladder wall thickness, and amniotic fluid index were not significantly correlated with GFR while PRA could differentiate between poor and better prognosis cases with PUV. Conclusions: Ultrasound was neither uniformly useful in diagnosing PUV antenatally, nor differentiating it from cases with non-PUV hydronephrosis. In congenital hydronephrosis, cord blood PRA was significantly higher in cases with PUV compared to non-PUV cases and fell significantly after valve ablation. Cord blood PRA could distinguish between poor and better prognosis cases with PUV.

  13. Alternativas a la elevación de seno maxilar: rehabilitación del sector posterior del maxilar atrófico mediante implantes pterigoideos Alternatives to maxillary sinus lift: posterior area of the atrophic maxilla rehabilitation by means pterigoideal implants

    Directory of Open Access Journals (Sweden)

    X. Rodríguez-Ciurana

    2008-12-01

    Full Text Available El primer y segundo molar son los dientes que se pierden más a menudo debido a la enfermedad periodontal y al exceso de fuerzas oclusales. A pesar de la frecuencia del edentulismo parcial del sector posterior raramente se ubican los implantes más allá de los premolares debido al aumento del índice de fallos. El escaso volumen óseo y la pobre mineralización del sector posterior del maxilar comprometen la viabilidad de las rehabilitaciones con implantes a largo plazo. Además, la cresta ósea a nivel del seno maxilar, en el maxilar atrófico, no suele permitir el anclaje de implantes de 10 mm. Se han propuesto varias técnicas para rehabilitar el sector posterior del maxilar atrófico: implantes cortos, extensiones protésicas, injerto sinusal, implante cigomático. El implante pterigoideo es otro de los posibles tratamientos para rehabilitar el sector posterior del maxilar atrófico. Anclado en el hueso cortical de la apófisis del esfenoides el implante pterigoideo evita la necesidad de injertar o utilizar extensiones protésicas. El objetivo de este artículo es analizar las indicaciones, la técnica, complicaciones y supervivencia del implante pterigoideo en el sector posterior del maxilar atrófico.The first and second molar are the teeth most commonly lost in the maxilla, mainly due to periodontal disease and excessive occlusal force. 1 Although partial edentulism of the posterior maxilla is common, implants are seldom placed distal to the premolars because failure rates in the posterior maxilla have historically been high. Poor volume and low density of bone are the worst conditions for long-term anchorage in the maxilla. 7 Moreover, bone under the maxillary sinus, in the atrophic maxilla, is usually insufficient to enable placement of 10 mm implants. Several techniques have been proposed to restore the atrophic posterior maxilla: short implants, prosthetic cantilevers, sinus bone graft, zigomatic fixtures. Pterygoid implants are

  14. Cortical Gating of Oropharyngeal Sensory Stimuli

    OpenAIRE

    KarenWheeler-Hegland

    2010-01-01

    Somatosensory evoked potentials provide a measure of cortical neuronal activation in response to various types of sensory stimuli. In order to prevent flooding of the cortex with redundant information various sensory stimuli are gated cortically such that response to stimulus 2 (S2) is significantly reduced in amplitude compared to stimulus 1 (S1). Upper airway protective mechanisms, such as swallowing and cough, are dependent on sensory input for triggering and modifying their motor output. ...

  15. Astrocytic regulation of cortical UP states

    OpenAIRE

    Poskanzer, Kira E.; Yuste, Rafael

    2011-01-01

    The synchronization of neuronal assemblies during cortical UP states has been implicated in computational and homeostatic processes, but the mechanisms by which this occurs remain unknown. To investigate potential roles of astrocytes in synchronizing cortical circuits, we electrically activated astrocytes while monitoring the activity of the surrounding network with electrophysiological recordings and calcium imaging. Stimulating a single astrocyte activates other astrocytes in the local circ...

  16. Convergent cortical innervation of striatal projection neurons

    OpenAIRE

    Kress, Geraldine J.; Yamawaki, Naoki; Wokosin, David L.; Wickersham, Ian R.; Gordon M. G Shepherd; Surmeier, D. James

    2013-01-01

    Anatomical studies have led to the assertion that intratelencephalic (IT) and pyramidal tract (PT) cortical neurons innervate different striatal projection neurons. To test this hypothesis, the responses of mouse striatal neurons to optogenetic activation of IT and PT axons were measured. Contrary to expectation, direct and indirect pathway striatal spiny projection neurons (SPNs) responded to both IT and PT activation, arguing that these cortical networks innervate both striatal projection n...

  17. Cortical thickness gradients in structural hierarchies

    OpenAIRE

    Wagstyl, Konrad; Ronan, Lisa; Goodyer, Ian M.; Fletcher, Paul C.

    2015-01-01

    MRI, enabling in vivo analysis of cortical morphology, offers a powerful tool in the assessment of brain development and pathology. One of the most ubiquitous measures used—the thickness of the cortex—shows abnormalities in a number of diseases and conditions, but the functional and biological correlates of such alterations are unclear. If the functional connotations of structural MRI measures are to be understood, we must strive to clarify the relationship between measures such as cortical t...

  18. Multimodal connectivity mapping of the human left anterior and posterior lateral prefrontal cortex.

    Science.gov (United States)

    Reid, Andrew T; Bzdok, Danilo; Langner, Robert; Fox, Peter T; Laird, Angela R; Amunts, Katrin; Eickhoff, Simon B; Eickhoff, Claudia R

    2016-06-01

    Working memory is essential for many of our distinctly human abilities, including reasoning, problem solving, and planning. Research spanning many decades has helped to refine our understanding of this high-level function as comprising several hierarchically organized components, some which maintain information in the conscious mind, and others which manipulate and reorganize this information in useful ways. In the neocortex, these processes are likely implemented by a distributed frontoparietal network, with more posterior regions serving to maintain volatile information, and more anterior regions subserving the manipulation of this information. Recent meta-analytic findings have identified the anterior lateral prefrontal cortex, in particular, as being generally engaged by working memory tasks, while the posterior lateral prefrontal cortex was more strongly associated with the cognitive load required by these tasks. These findings suggest specific roles for these regions in the cognitive control processes underlying working memory. To further characterize these regions, we applied three distinct seed-based methods for determining cortical connectivity. Specifically, we employed meta-analytic connectivity mapping across task-based fMRI experiments, resting-state BOLD correlations, and VBM-based structural covariance. We found a frontoparietal pattern of convergence which strongly resembled the working memory networks identified in previous research. A contrast between anterior and posterior parts of the lateral prefrontal cortex revealed distinct connectivity patterns consistent with the idea of a hierarchical organization of frontoparietal networks. Moreover, we found a distributed network that was anticorrelated with the anterior seed region, which included most of the default mode network and a subcomponent related to social and emotional processing. These findings fit well with the internal attention model of working memory, in which representation of

  19. Effect of posterior decompression extent on biomechanical parameters of the spinal cord in cervical ossification of the posterior longitudinal ligament.

    Science.gov (United States)

    Khuyagbaatar, Batbayar; Kim, Kyungsoo; Park, Won Man; Kim, Yoon Hyuk

    2016-06-01

    Ossification of the posterior longitudinal ligament is a common cause of the cervical myelopathy due to compression of the spinal cord. Patients with ossification of the posterior longitudinal ligament usually require the decompression surgery, and there is a need to better understand the optimal surgical extent with which sufficient decompression without excessive posterior shifting can be achieved. However, few quantitative studies have clarified this optimal extent for decompression of cervical ossification of the posterior longitudinal ligament. We used finite element modeling of the cervical spine and spinal cord to investigate the effect of posterior decompression extent for continuous-type cervical ossification of the posterior longitudinal ligament on changes in stress, strain, and posterior shifting that occur with three different surgical methods (laminectomy, laminoplasty, and hemilaminectomy). As posterior decompression extended, stress and strain in the spinal cord decreased and posterior shifting of the cord increased. The location of the decompression extent also influenced shifting. Laminectomy and laminoplasty were very similar in terms of decompression results, and both were superior to hemilaminectomy in all parameters tested. Decompression to the extents of C3-C6 and C3-C7 of laminectomy and laminoplasty could be considered sufficient with respect to decompression itself. Our findings provide fundamental information regarding the treatment of cervical ossification of the posterior longitudinal ligament and can be applied to patient-specific surgical planning. PMID:26951839

  20. Dexmedetomidine sedation in painful posterior segment surgery

    Directory of Open Access Journals (Sweden)

    Mansour A

    2012-12-01

    Full Text Available Ahmad Mansour,1,2 Samar Taha31Department of Ophthalmology, American University of Beirut, Beirut, Lebanon; 2Rafik Hariri University Hospital, Beirut, Lebanon; 3Department of Anesthesiology, American University of Beirut, Beirut, LebanonPurpose: To present a case series on the use of dexmedetomidine (Precedex sedation in painful posterior segment surgery performed under topical anesthesia, similar to its use in cataract surgery.Methods: A prospective review of cases that had posterior segment surgery under topical anesthesia and that needed sedation. Dexmedetomidine-loading infusion was 1 mcg/kg over 10 minutes, followed by a maintenance infusion (0.5 mcg/kg/h.Results: Nine patients were operated on under topical anesthesia: two scleral buckle, five cryopexy, one scleral laceration, and one pars plana vitrectomy with very dense laser therapy in an albinotic fundus; six patients had retinal detachment. General or local anesthesia were not possible due to medical or ocular morbidities, use of anticoagulants, or the surgery plan changed intraoperatively when new pathologies were discovered. The surgeon achieved good surgical control in eight of nine cases, with one patient having ocular and bodily movements that were disturbing. Six patients had no pain, while three patients reported mild pain. No adverse effects were noted and all patients had successful surgical outcomes. Heart rate, blood pressure, and oxygen saturation were well controlled throughout the procedures. The most frequent adverse reactions of dexmedetomidine reported in the literature in less than 5% (hypotension, bradycardia, and dry mouth were not recorded in the present study.Conclusion: When a surgeon has planned to do a pars plana vitrectomy under topical anesthesia and the surgical situation dictates the addition of cryopexy, scleral buckle, or intense laser retinopexy, then sedation with dexmedetomidine can help in the control of ocular pain in the majority of cases, with good

  1. Mitral valve mechanics following posterior leaflet patch augmentation

    DEFF Research Database (Denmark)

    Rahmani, Azadeh; Rasmussen, Ann Qvist; Hønge, Jesper Langhoff; Ostli, Bjorn; Levine, Robert A.; Hagège, Albert; Nygaard, Hans; Nielsen, Sten L; Jensen, Morten Ølgaard Jegstrup

    2013-01-01

    tendineae emanating from the posterior papillary muscle in a FIMR-simulated valve, following posterior leaflet patch augmentation. Methods: Mitral valves were obtained from 12 pigs (body weight 80 kg). An in vitro test set-up simulating the left ventricle was used to hold the valves. The left ventricular...... pressure was regulated with water to simulate different static pressures during valve closure. A standardized oval pericardial patch (17 × 29 mm) was introduced into the posterior leaflet from mid P2 to the end of the P3 scallop. Dedicated miniature transducers were used to record the forces exerted on the...... chordae tendineae. Data were acquired before and after 12 mm posterior and 5 mm apical posterior papillary muscle displacement to simulate the effect from one of the main contributors of FIMR, before and after patch augmentation. Results: The effect of displacing the posterior papillary muscle induced...

  2. Microscopic Posterior Transdural Resection of Cervical Retro-Odontoid Pseudotumors

    OpenAIRE

    Fujiwara, Yasushi; Manabe, Hideki; Sumida, Tadayoshi; Tanaka, Nobuhiro; Hamasaki, Takahiko

    2015-01-01

    Retro-odontoid pseudotumors are noninflammatory masses formed posterior to the odontoid process. Because of their anatomy, the optimal surgical approach for resecting pseudotumors is controversial. Conventionally, 3 approaches are used: the anterior transoral approach, the lateral approach, and the posterior extradural approach; however, each approach has its limitations. The posterior extradural approach is the most common; however, it remains challenging due to severe epidural veins. Althou...

  3. Bilateral posterior shoulder dislocation after electrical shock: A case report

    OpenAIRE

    Ismail Emre Ketenci; Tahir Mutlu Duymus; Ayhan Ulusoy; Hakan Serhat Yanik; Serhat Mutlu; Mehmet Oguz Durakbasa

    2015-01-01

    Introduction: Posterior dislocation of the shoulder is a rare and commonly missed injury. Unilateral dislocations occur mostly due to trauma. Bilateral posterior shoulder dislocations are even more rare and result mainly from epileptic seizures. Electrical injury is a rare cause of posterior shoulder dislocation. Injury mechanism in electrical injury is similar to epileptic seizures, where the shoulder is forced to internal rotation, flexion and adduction. Presentation of case: This report...

  4. Rupture of Posterior Cruciate Ligament: Diagnosis and Treatment Principles

    OpenAIRE

    Lee, Beom Koo; Nam, Shin Woo

    2011-01-01

    Posterior cruciate ligament (PCL) injuries associated with multiple ligament injuries can be easily diagnosed, but isolated PCL tears are less symptomatic, very difficult to diagnose, and frequently misdiagnosed. If a detailed investigation of the history of illness suggests a PCL injury, careful physical examinations including the posterior drawer test, dial test, varus and valgus test should be done especially if the patient complains of severe posterior knee pain in >90° of flexion. Vascul...

  5. The enigmatic diagnosis of posterior tibialis tendon rupture.

    OpenAIRE

    Marcus, R E; Pfister, M. E.

    1993-01-01

    Posterior tibialis tendon rupture is a diagnosis that is often missed. This is thought to be secondary to nonspecific clinical findings and the lack of any laboratory or radiographic test to reliably confirm the diagnosis. We report sixteen cases of surgically confirmed posterior tibialis tendon rupture. Based on our review of these patients, the diagnosis of posterior tibialis tendon rupture should be strongly suspected in the adult patient presenting with a history of a twisting ankle injur...

  6. Anatomic Double-Bundle Posterior Cruciate Ligament Reconstruction

    OpenAIRE

    Chahla, Jorge; Nitri, Marco; Civitarese, David; Dean, Chase S.; Moulton, Samuel G.; LaPrade, Robert F.

    2016-01-01

    The posterior cruciate ligament (PCL) is known to be the main posterior stabilizer of the knee. Anatomic single-bundle PCL reconstruction, focusing on reconstruction of the larger anterolateral bundle, is the most commonly performed procedure. Because of the residual posterior and rotational tibial instability after the single-bundle procedure and the inability to restore the normal knee kinematics, an anatomic double-bundle PCL reconstruction has been proposed in an effort to re-create the n...

  7. RELATIONSHIP OF TRANSVERSAL ASYMMETRIC FACE AND UNILATERAL POSTERIOR CROSSBITE

    OpenAIRE

    Indah Dwinursanty; Krisnawati Krisnawati; Maria Purbiati

    2006-01-01

    Unilateral posterior crossbite is commonly seen in mixed dentition, but it couldn’t be self corrected. If this condition is not treated properly, it could lead to asymmetric face. Asymmetric face with unilateral posterior crossbite could make the treatment process more difficult. The objective of this study is to find out the relationship between transversal skeletal asymmetry and unilateral posterior crossbite. Patients older than 13 years with skeletal asymmetric face, who had never undergo...

  8. Towards a “canonical” agranular cortical microcircuit

    OpenAIRE

    Beul, Sarah F.; Hilgetag, Claus C.

    2015-01-01

    Based on regularities in the intrinsic microcircuitry of cortical areas, variants of a 'canonical' cortical microcircuit have been proposed and widely adopted, particularly in computational neuroscience and neuroinformatics. However, this circuit is founded on striate cortex, which manifests perhaps the most extreme instance of cortical organization, in terms of a very high density of cells in highly differentiated cortical layers. Most other cortical regions have a less well differentiated a...

  9. Iodine-125 radiation of posterior uveal melanoma

    Energy Technology Data Exchange (ETDEWEB)

    Packer, S.

    1987-12-01

    Twenty-eight cases of posterior choroidal melanoma were treated with iodine-125 in gold eye plaques. Eleven cases were located within 3.0 mm of the optic nerve (group A), nine were within 3.0 mm of the fovea (group B), and eight were within 3.0 mm of the optic nerve and fovea (group C). The mean follow-up of group A was 46.3 months; group B, 25.5 months; and group C, 42.7 months. Complications included macular edema, cataract and tumor growth. Visual acuity remained within two lines of that tested preoperatively for 4 of 11 patients in group A, 4 of 9 in group B, and 5 of 8 in group C. These results with iodine-125 suggest it as an appropriate treatment for patients with choroidal melanoma located near optic nerve and/or macula.

  10. Rapid Maxillary Expansion without Posterior Anchorage.

    Science.gov (United States)

    Oliveira, Adauê; Amaral, Cássia

    2016-01-01

    This work aimed to evaluate an alternative form of maxillary expansion anchored with mini-implants. A patient 12 years, class III in permanent canine teeth, with multiple agenesis of upper posterior teeth was treated with the aid of four mini-implants in the palate and Haas modified type appliance. During the period of expansion, an interincisal diastema was observed as the first clinical sign of disjunction of the sutures. After correction of cross bite, the expansion of the palate was confirmed by upper occlusal radiographs. Thus, the evaluations showed that the technique was effective and that new scientific studies should be conducted to further develop this subject. Keywords: Appliances; Biomechanics; Implants; Malocclusions PMID:27319047

  11. Imaging of the posterior pelvic floor

    Energy Technology Data Exchange (ETDEWEB)

    Stoker, Jaap [Department of Radiology, Academic Medical Center, University of Amsterdam (Netherlands); Bartram, Clive I.; Halligan, Steve [Intestinal Imaging Centre, St. Mark' s Hospital, London (United Kingdom)

    2002-04-01

    Disorders of the posterior pelvic floor are relatively common. The role of imaging in this field is increasing, especially in constipation, prolapse and anal incontinence, and currently imaging is an integral part of the investigation of these pelvic floor disorders. Evacuation proctography provides both structural and functional information for rectal voiding and prolapse. Dynamic MRI may be a valuable alternative as the pelvic floor muscles are visualised, and it is currently under evaluation. Endoluminal imaging is important in the management of anal incontinence. Both endosonography and endoanal MRI can be used for detection of anal sphincter defects. Endoanal MRI has the advantage of simultaneously evaluating external sphincter atrophy, which is an important predictive factor for the outcome of sphincter repair. Many aspects of constipation and prolapse remain incompletely understood and treatment is partly empirical; however, imaging has a central role in management to place patients into treatment-defined groups. (orig.)

  12. Arthroscopic Reverse Remplissage for Posterior Instability.

    Science.gov (United States)

    Lavender, Chad D; Hanzlik, Shane R; Pearson, Sara E; Caldwell, Paul E

    2016-02-01

    Posterior shoulder dislocation is an unusual injury often associated with electrical shock or seizure. As with anterior instability, patients frequently present with an impaction injury to the anterior aspect of the humeral head known as a "reverse Hill-Sachs lesion." The treatment of this bony defect is controversial, and multiple surgical procedures to fill the defect in an effort to decrease recurrence have been described. Most of the reports have focused on an open approach using variations of lesser tuberosity and subscapularis transfers, bone allograft, and even arthroplasty to assist with persistent instability. We advocate an arthroscopic technique that involves a suture anchor-based distal tenodesis of the subscapularis tendon or a reverse remplissage procedure. PMID:27073776

  13. Arthroscopic Reverse Remplissage for Posterior Instability

    Science.gov (United States)

    Lavender, Chad D.; Hanzlik, Shane R.; Pearson, Sara E.; Caldwell, Paul E.

    2016-01-01

    Posterior shoulder dislocation is an unusual injury often associated with electrical shock or seizure. As with anterior instability, patients frequently present with an impaction injury to the anterior aspect of the humeral head known as a “reverse Hill-Sachs lesion.” The treatment of this bony defect is controversial, and multiple surgical procedures to fill the defect in an effort to decrease recurrence have been described. Most of the reports have focused on an open approach using variations of lesser tuberosity and subscapularis transfers, bone allograft, and even arthroplasty to assist with persistent instability. We advocate an arthroscopic technique that involves a suture anchor–based distal tenodesis of the subscapularis tendon or a reverse remplissage procedure. PMID:27073776

  14. MR imaging of posterior cruciate ligament injuries

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, Nobuyuki [Tsukuba Univ., Ibaraki (Japan). Hospital; Niitsu, Mamoru; Itai, Yuji; Sato, Motohiro; Kujiraoka, Yuka; Ikeda, Kotaro; Kanamori, Akihiro

    2001-07-01

    Posterior cruciate ligament (PCL) injuries are less frequent than anterior cruciate ligament (ACL) injuries, but are presumably more common than once thought. Thirty-nine patients with PCL injuries identified on MR images were studied. The criteria for PCL injury were complete tear, partial tear, and avulsion fracture. The approximate site of a partial tear was categorized as proximal, midsubstance, distal, or combination. Fourteen patients (35.9%) had complete tears of the PCL, 21 patients (53.8%) had partial tears, and four patients (10.3%) had avulsion fractures. A total of 12 patients (30.7%) had isolated PCL injuries, while the remaining 27 patients demonstrated evidence of other coexistent knee injuries, such as meniscal tears and ligamentous injuries. Of coexistent knee injuries, meniscal tears (18 patients, 46.2%) were most often seen. (author)

  15. MR imaging of posterior cruciate ligament injuries

    International Nuclear Information System (INIS)

    Posterior cruciate ligament (PCL) injuries are less frequent than anterior cruciate ligament (ACL) injuries, but are presumably more common than once thought. Thirty-nine patients with PCL injuries identified on MR images were studied. The criteria for PCL injury were complete tear, partial tear, and avulsion fracture. The approximate site of a partial tear was categorized as proximal, midsubstance, distal, or combination. Fourteen patients (35.9%) had complete tears of the PCL, 21 patients (53.8%) had partial tears, and four patients (10.3%) had avulsion fractures. A total of 12 patients (30.7%) had isolated PCL injuries, while the remaining 27 patients demonstrated evidence of other coexistent knee injuries, such as meniscal tears and ligamentous injuries. Of coexistent knee injuries, meniscal tears (18 patients, 46.2%) were most often seen. (author)

  16. Ectomesenchymal chondromyxoid tumour of the posterior tongue.

    Science.gov (United States)

    Cardin, Marie-Josée; Fiset, Pierre Olivier; Zeitouni, Anthony G; Caglar, Derin

    2014-01-01

    Ectomesenchymal chondromyxoid tumor (ECMT) is a rare benign neoplasm arising in the tongue. With only 45 cases reported in the literature, there are several unique features defining this lesion. Firstly, almost all patients present with an asymptomatic slow growing mass on the anterior dorsum of the tongue. At the microscopic level, it is recognizable as a well-circumscribed unencapsulated proliferation of uniform round to fusiform cells embedded in a chondromyxoid matrix. Lastly, the immunohistochemistry profile is characterised by positivity for glial fibrillary acidic protein and frequent positivity for S-100 and cytokeratins. We report a case of a mass located on the posterior dorsum of the tongue and meeting the aforementioned morphological and immunohistochemical criteria of ECMT. PMID:24288100

  17. Tibial Tuberosity-Posterior Cruciate Ligament Distance.

    Science.gov (United States)

    Daynes, Jake; Hinckel, Betina Bremer; Farr, Jack

    2016-08-01

    When trochlear dysplasia is present, it is difficult to measure the tibial tuberosity to trochlear groove (TT-TG) distance. A new measurement to assess tuberosity position was recently described by Seitlinger et al, which avoids the difficulty of identifying the TG as it references the posterior cruciate ligament (PCL). To evaluate the reproducibility of the Seitlinger et al findings, 42 knees in 41 patients with a documented history of recurrent patellar instability and 84 knees in patients with no history of patellar instability or patellofemoral symptoms were evaluated with magnetic resonance imaging. The TT-PCL distance was increased in the instability group (mean, 21.6 mm) compared with the control group (mean, 19.0 mm). The TT-PCL distance is an independent risk factor for patients with recurrent patellar instability. Its role in surgical planning remains to be determined. PMID:26509659

  18. Iodine-125 radiation of posterior uveal melanoma

    International Nuclear Information System (INIS)

    Twenty-eight cases of posterior choroidal melanoma were treated with iodine-125 in gold eye plaques. Eleven cases were located within 3.0 mm of the optic nerve (group A), nine were within 3.0 mm of the fovea (group B), and eight were within 3.0 mm of the optic nerve and fovea (group C). The mean follow-up of group A was 46.3 months; group B, 25.5 months; and group C, 42.7 months. Complications included macular edema, cataract and tumor growth. Visual acuity remained within two lines of that tested preoperatively for 4 of 11 patients in group A, 4 of 9 in group B, and 5 of 8 in group C. These results with iodine-125 suggest it as an appropriate treatment for patients with choroidal melanoma located near optic nerve and/or macula

  19. Posterior Reversible Encephalopathy Syndrome in Our Setup

    International Nuclear Information System (INIS)

    Objectives: To assess the clinical presentation and neuroimaging abnormalities in a series of patients diagnosed as posterior reversible encephalopathy syndrome at Military Hospital Rawalpindi. Study Design: Case series study. Place and Duration: Study was carried out at Military Hospital Rawalpindi form December 01st, 2011 to May 31st, 2012. Patients and Methods: Study included all the cases of the Posterior reversible encephalopathy syndrome (PRES) admitted in the wards and intensive care unit (ITC). Neuroimaging was done and all the studies were reviewed by independent neuroradiologist. Different clinical and laboratory variables were also studied and correlated with neuroimaging. Follow up ws done to look for the prognosis. Results: Of the seven patients labelled as PRES two were male and five were female. Two patients were over 50 years of age, out of them one was male and one was female. One patient had end stage renal disease (ESRD) secondary to diabetes mellitus (DM) and hypertension (HTN), one had eclampsia, one had pregnancy-induced hypertension (PIH) and one had just uncontrolled HTN. Peak spontaneous bacterial peritonitis (SBP) in 5 cases was 210 mm of Hg, four of which had seizures. Rest two had spontaneous bacterial peritonitis (SBP) of 160 out of which one developed seizures. Total out of 7, 5 experienced seizures and altered conscious state, rest two only had confusion. One patient had papilloedema. Follow up was done after 06 weeks, 02 patients died, 05 remained alive and symptoms of PRES had vanished. Conclusion: PRES is a neurological emergency, presents with a variety of symptoms and has a specific neuroimaging pattern. Early recognition and prompt treatment result in a good neurological outcome. (author)

  20. Experimental models for posterior capsule opacification research.

    Science.gov (United States)

    Wormstone, Ian Michael; Eldred, Julie Ann

    2016-01-01

    Millions of people worldwide are blinded due to cataract formation. At present the only means of treating a cataract is through surgical intervention. A modern cataract operation involves the creation of an opening in the anterior lens capsule to allow access to the fibre cells, which are then removed. This leaves in place a capsular bag that comprises the remaining anterior capsule and the entire posterior capsule. In most cases, an intraocular lens is implanted into the capsular bag during surgery. This procedure initially generates good visual restoration, but unfortunately, residual lens epithelial cells undergo a wound-healing response invoked by surgery, which in time commonly results in a secondary loss of vision. This condition is known as posterior capsule opacification (PCO) and exhibits classical features of fibrosis, including hyperproliferation, migration, matrix deposition, matrix contraction and transdifferentiation into myofibroblasts. These changes alone can cause visual deterioration, but in a significant number of cases, fibre differentiation is also observed, which gives rise to Soemmering's ring and Elschnig's pearl formation. Elucidating the regulatory factors that govern these events is fundamental in the drive to develop future strategies to prevent or delay visual deterioration resulting from PCO. A range of experimental platforms are available for the study of PCO that range from in vivo animal models to in vitro human cell and tissue culture models. In the current review, we will highlight some of the experimental models used in PCO research and provide examples of key findings that have resulted from these approaches. PMID:25939555

  1. Telegammatherapy in some posterior orbital diseases

    International Nuclear Information System (INIS)

    Objective: The large penumbra (2-3 cm) of the standard fields of the 60Co equipment necessitates the implementation of a technique for sparing of the eye lenses. The report analyses the results from the irradiation in some disease of the posterior orbit. Material and methods: From July 2000 to December 2001, 22 patients have been submitted to telegammatherapy of the posterior orbit. The larger group is with thyroid associated ophthalmopathy (TAO) - 16, and 3 patients with choroidal metastases (CM) and 3 with senile macular degeneration (SMD). The results assessment in TAO is made according to the criteria for assessment of the ophthalmopathy index, and in the rest by regular ophthalmological examinations. The applied doses are 20 Gy distributed in 10 fractions for 2 weeks for TAO and 40 - 44 Gy in 20 - 200 fractions for 4 - 4,5 weeks. Results: The general clinical response two months after the radiotherapy according to the Donaldson criteria for TAO patients is excellent in 2/25 (13%, good in 7/15 (47%), satisfying in 5/15 (33%) and without response in 1/15 (6%). The best response is achieved towards the corneal, soft tissue changes and the vision sharpness decrease, when the reverse development of the exophthalmos is weaker, but improving after a longer period. The three patients with CM have been followed-up till the end of their lives - 18, 11 and 7 months respectively. In one of them the vision sharpness has remained 1.0, and in the others it has decreased to 0.4. No early or late complications from the orbital radiotherapy are observed so far. Conclusions: The orbital irradiation is a highly effective method for patients with progressive forms of TAO. The radiotherapy of CM saves the eye and the vision sharpness till the end of the patients life

  2. Management of posterior fossa gliomas in children

    Directory of Open Access Journals (Sweden)

    K Sridhar

    2011-01-01

    Full Text Available Brain tumours form the most common type of solid tumour in children and more that 50% of these are infratentorial. Cerebellar astrocytomas and brain stem gliomas are the commonest posterior fossa glial tumours in children. Cerebellar astrocytomas represent up to 10% of all primary brain tumours and up to 25% of posterior fossa tumors in children, with Low grade gliomas forming the commonest of the cerebellar gliomas. They commonly present with symptoms and signs of raised intracranial pressure due to obstructive hydrocephalus. Radiologically they may be solid or cystic with or without a mural nodule. Surgical excision is the mainstay of treatment and forms the most consistent factor influencing progression free and long term survival. While majority of the tumours are pilocytic astrocytomas, they may also be fibrillary astrocytomas or even high grade tumours. Tumour histology does not appear to be an independent factor in the prognosis of these children, and therefore no palliative treatment after surgery is advocated. Brain stem gliomas account for approximately 10% of all pediatric brain tumours. Cranial nerve signs, ataxia and cerebellar signs with or without symptoms and signs of raised intracranial pressure are classically described symptoms and signs. Radiographic findings and clinical correlates can be used to categorize brain stem tumours into four types: diffuse, focal, exophytic and cervicomedullary. Histologically most brain stem gliomas are fibrillary astrocytomas. Diffuse brain stem gliomas are the most commonly seen tumour in the brain stem. These lesions are malignant high grade fibrillary astrocytomas. Focal tumours of the brain stem are demarcated lesions generally less than 2 cms in size, without associated edema. Most commonly seen in the midbrain or medulla, they form a heterogeneous pathological group, showing indolent growth except when the lesion is a PNET. Dorsally exophytic tumours lie in the fourth ventricle, while

  3. Posterior mediastinal teratoma diagnosis by computerized tomography and ultrasonography

    Energy Technology Data Exchange (ETDEWEB)

    Choo, Yeon Myung; Im, Chung Kie; Yeon, Kyung Mo; Han, Man Chung [Seoul National University College of Medicine, Seoul (Korea, Republic of)

    1984-09-15

    Teratomas, usually arising in the anterior mediastinum, are very uncommon in the posterior mediastinum. Embryologic development of anterior mediastinal teratoma is thought to be from thymic anlage which descends from the third bronchial cleft and pouch, while that of posterior mediastinal teratoma is thought to be from the remnant of notochord. CT findings of posterior mediastinal teratomas are not different from teratomas elsewhere, containing fat, calcification, soft tissue and thick walled cyst. Ultrasonographic findings are mixed echogenic mass containing cystic portion, highly reflective solid portion and area of acoustic shadowing. Authors recently experienced 2 cases of surgically proven posterior mediastinal teratoma and report with review of literature.

  4. Patterns of cortical thinning in idiopathic rapid eye movement sleep behavior disorder.

    Science.gov (United States)

    Rahayel, Shady; Montplaisir, Jacques; Monchi, Oury; Bedetti, Christophe; Postuma, Ronald B; Brambati, Simona; Carrier, Julie; Joubert, Sven; Latreille, Véronique; Jubault, Thomas; Gagnon, Jean-François

    2015-04-15

    Idiopathic rapid eye movement sleep behavior disorder is a parasomnia that is a risk factor for dementia with Lewy bodies and Parkinson's disease. Brain function impairments have been identified in this disorder, mainly in the frontal and posterior cortical regions. However, the anatomical support for these dysfunctions remains poorly understood. We investigated gray matter thickness, gray matter volume, and white matter integrity in patients with idiopathic rapid eye movement sleep behavior disorder. Twenty-four patients with polysomnography-confirmed idiopathic rapid eye movement sleep behavior disorder and 42 healthy individuals underwent a 3-tesla structural and diffusion magnetic resonance imaging examination using corticometry, voxel-based morphometry, and diffusion tensor imaging. In the patients with idiopathic rapid eye movement sleep behavior disorder, decreased cortical thickness was observed in the frontal cortex, the lingual gyrus, and the fusiform gyrus. Gray matter volume was reduced in the superior frontal sulcus only. Patients showed no increased gray matter thickness or volume. Diffusion tensor imaging analyses revealed no significant white matter differences between groups. Using corticometry in patients with idiopathic rapid eye movement sleep behavior disorder, several new cortical regions with gray matter alterations were identified, similar to those reported in dementia with Lewy bodies and Parkinson's disease. These findings provide some anatomical support for previously identified brain function impairments in this disorder. PMID:24676967

  5. Higher cortical modulation of pain perception in the human brain: Psychological determinant.

    Science.gov (United States)

    Chen, Andrew Cn

    2009-10-01

    Pain perception and its genesis in the human brain have been reviewed recently. In the current article, the reports on pain modulation in the human brain were reviewed from higher cortical regulation, i.e. top-down effect, particularly studied in psychological determinants. Pain modulation can be examined by gene therapy, physical modulation, pharmacological modulation, psychological modulation, and pathophysiological modulation. In psychological modulation, this article examined (a) willed determination, (b) distraction, (c) placebo, (d) hypnosis, (e) meditation, (f) qi-gong, (g) belief, and (h) emotions, respectively, in the brain function for pain modulation. In each, the operational definition, cortical processing, neuroimaging, and pain modulation were systematically deliberated. However, not all studies had featured the brain modulation processing but rather demonstrated potential effects on human pain. In our own studies on the emotional modulation on human pain, we observed that emotions could be induced from music melodies or pictures perception for reduction of tonic human pain, mainly in potentiation of the posterior alpha EEG fields, likely resulted from underneath activities of precuneous in regulation of consciousness, including pain perception. To sum, higher brain functions become the leading edge research in all sciences. How to solve the information bit of thinking and feeling in the brain can be the greatest challenge of human intelligence. Application of higher cortical modulation of human pain and suffering can lead to the progress of social humanity and civilization. PMID:19784081

  6. Non-traumatic cortical subarachnoid haemorrhage: diagnostic work-up and aetiological background

    International Nuclear Information System (INIS)

    Only 15% of all subarachnoid haemorrhages (SAHs) are not of aneurysmal origin. Among those, circumscribed SAHs along the cortical convexity are rare and have only been described in singular case reports so far. Here, we present a collection of 12 cases of SAH along the convexity, of non-traumatic origin. Over a period of 10 years, 12 cases of circumscribed SAH along the convexity were identified at our clinic. The clinical presentations, neuroradiological SAH characteristics, further diagnostic work-up to identify the underlying aetiologies, the therapy and clinical outcome were analysed. The patients' chief complaints were unspecific cephalgia, focal or generalised seizures and focal neurological deficits. Typical signs of basal SAH, such as nuchal rigidity, thunderclap-headache or alteration of consciousness, were rare. Magnetic resonance imaging (MRI) and digital subtraction angiography (DSA) revealed different aetiologies, namely postpartal posterior encephalopathy (three), cerebral vasculitis (two), dural sinus thrombosis (two), cortical venous thrombosis (one), intracerebral abscesses (one) and cerebral cavernoma (one). Two cases remained unresolved. Treatment of the underlying disease and symptomatic medication led to good clinical outcome in almost all cases. On the basis of these findings, we demonstrate that the clinical presentation, localisation and aetiology of cortical SAH differ clearly from other SAHs. A diagnostic work-up with MRI and eventually DSA is essential. Mostly, the causative disease can be identified, and specific treatment allows a favourable outcome. (orig.)

  7. EEG frequency analysis of cortical brain activities induced by effect of light touch.

    Science.gov (United States)

    Ishigaki, Tomoya; Ueta, Kozo; Imai, Ryota; Morioka, Shu

    2016-06-01

    In human postural control, touching a fingertip to a stable object with a slight force (EEG frequency analysis to investigate the cortical brain activity associated with the LT effect when attentional focus was strictly controlled with the eyes closed during standing (i.e., control, fixed-point touch, sway-referenced touch, and only fingertip attention). We used EEG to measure low-alpha (about 8-10 Hz) and high-alpha rhythm (about 10-12 Hz) task-related power decrease/increase (TRPD/TRPI). The LT effect was apparent only when the subject acquired the stable external spatial reference (i.e., fixed-point touch). Furthermore, the LT-specific effect increased the high-alpha TRPD of two electrodes (C3, P3), which were mainly projected from cortical brain activities of the left primary sensorimotor cortex area and left posterior parietal cortex area. Furthermore, there was a negative correlation between the LT effect and increased TRPD of C3. In contrast, the LT effect correlated positively with increased TRPD of P3. These results suggest that central and parietal high-alpha TRPD of the contralateral hemisphere reflects the sensorimotor information processing and sensory integration for the LT effect. These novel findings reveal a partial contribution of a cortical neural mechanism for the LT effect. PMID:26758719

  8. Estimulação elétrica neuromuscular de média freqüência (russa em cães com atrofia muscular induzida Medium frequency neuromuscular electrical stimulation (russian in dogs with induced muscle atrophy

    Directory of Open Access Journals (Sweden)

    Charles Pelizzari

    2008-06-01

    Full Text Available A estimulação elétrica neuromuscular (EENM de média freqüência (Russa ou de Kotz pode ser empregada para a recuperação de massa muscular em animais apresentando atrofia muscular por desuso. Assim, o objetivo deste trabalho foi empregar a EENM de média freqüência no quadríceps femoral de cães com atrofia muscular induzida, avaliando-se a ocorrência de ganho de massa. Foram utilizados oito cães em dois grupos denominados de GI ou controle e de GII ou tratado. Para a indução da atrofia muscular, a articulação fêmoro-tíbio-patelar esquerda foi imobilizada por 30 dias. Após 48 horas da remoção, foi realizada a EENM nos cães do grupo II, três vezes por semana, com intervalo de 48 horas cada sessão, pelo período de 60 dias. Foram avaliadas a mensuração da perimetria da coxa, da goniometria do joelho, as enzimas creatina-quinase (CK e morfometria das fibras musculares em cortes transversais do músculo vasto lateral, colhido mediante a biópsia muscular. A EENM foi empregada no músculo quadríceps femoral numa freqüência de 2.500Hz, largura de pulso de 50% e relação de tempo on/off de 1:2. Não houve diferença significativa quanto aos valores de perimetria da coxa e a atividade da enzima CK entre os grupos I e II. Na goniometria, houve diminuição significativa (PThe medium frequency neuromuscular electrical stimulation (NMES (Russa or Kotz is designed for recuperation of muscle mass in dogs with muscular atrophy in disuse. This study aims to utilize medium frequency NMES on the femoral quadriceps of dogs with induced muscular atrophy and evaluate the occurrence of gain in mass. Eight dogs in two groups denominated GI, or control, and GII, or treated were used. For the induction of muscular atrophy, the left femoral-tibial-patellar joint was immobilized for 30 days. NMES treatment began 48 hours after the removal of the immobilization device on dogs from group II and was carried out three times per week, with an

  9. Dynamic posterior stabilization of shoulder hemiarthroplasty in long-standing neglected posterior dislocation of the glenohumeral joint

    OpenAIRE

    Shyam Kumar A; Oakley Jeremy; Wootton Jamie

    2008-01-01

    Posterior dislocations of the shoulder are rare. They account for less than 3% of all shoulder dislocations. The treatment of neglected bilateral posterior dislocation of the shoulder is controversial. We present a novel operative technique to stabilize a shoulder hemiarthroplasty that we used in the treatment of a chronic posterior dislocation of a shoulder with an acute four-part fracture of the proximal humerus.

  10. Dynamic posterior stabilization of shoulder hemiarthroplasty in long-standing neglected posterior dislocation of the glenohumeral joint

    Directory of Open Access Journals (Sweden)

    Shyam Kumar A

    2008-01-01

    Full Text Available Posterior dislocations of the shoulder are rare. They account for less than 3% of all shoulder dislocations. The treatment of neglected bilateral posterior dislocation of the shoulder is controversial. We present a novel operative technique to stabilize a shoulder hemiarthroplasty that we used in the treatment of a chronic posterior dislocation of a shoulder with an acute four-part fracture of the proximal humerus.

  11. Anatomical substrates of the alerting, orienting and executive control components of attention: focus on the posterior parietal lobe.

    Directory of Open Access Journals (Sweden)

    Xuntao Yin

    Full Text Available Both neuropsychological and functional neuroimaging studies have identified that the posterior parietal lobe (PPL is critical for the attention function. However, the unique role of distinct parietal cortical subregions and their underlying white matter (WM remains in question. In this study, we collected both magnetic resonance imaging and diffusion tensor imaging (DTI data in normal participants, and evaluated their attention performance using attention network test (ANT, which could isolate three different attention components: alerting, orienting and executive control. Cortical thickness, surface area and DTI parameters were extracted from predefined PPL subregions and correlated with behavioural performance. Tract-based spatial statistics (TBSS was used for the voxel-wise statistical analysis. Results indicated structure-behaviour relationships on multiple levels. First, a link between the cortical thickness and WM integrity of the right inferior parietal regions and orienting performance was observed. Specifically, probabilistic tractography demonstrated that the integrity of WM connectivity between the bilateral inferior parietal lobules mediated the orienting performance. Second, the scores of executive control were significantly associated with the WM diffusion metrics of the right supramarginal gyrus. Finally, TBSS analysis revealed that alerting performance was significant correlated with the fractional anisotropy of local WM connecting the right thalamus and supplementary motor area. We conclude that distinct areas and features within PPL are associated with different components of attention. These findings could yield a more complete understanding of the nature of the PPL contribution to visuospatial attention.

  12. Aspectos clínicos e concentração sérica da creatina-quinase e lactato-desidrogenase em cães submetidos à fisioterapia após atrofia muscular induzida Clinical aspects and serum concentration creatina kinase and lactate dehydrogenase in dogs submitted to physiotherapy after induced muscle atrophy

    Directory of Open Access Journals (Sweden)

    Soraia Figueiredo de Souza

    2011-07-01

    Full Text Available Avaliou-se a resposta de diferentes protocolos fisioterapêuticos em cães após a indução de atrofia muscular por meio da imobilização do joelho por 30 dias. Os grupos foram denominados grupo C ou controle, grupo E (massagem, movimentação passiva e eletroterapia, grupo H (massagem, movimentação passiva e hidroterapia em esteira aquática e grupo EH (massagem, movimentação passiva, eletroterapia e hidroterapia em esteira aquática. Foram mensurados os graus de claudicação, arco do movimento, circunferência da coxa e a variação sérica das enzimas creatina-quinase e lactato-desidrogenase. De acordo com os resultados encontrados, foi possível concluir que as modalidades terapêuticas de massagem, movimentação passiva da articulação, estimulação elétrica neuromuscular e hidroterapia por caminhada em esteira aquática aceleram a recuperação clínica em cães com atrofia muscular induzida.The response of different physiotherapeutic treatment protocols was evaluated in dogs after muscle atrophy induced by joint immobilization for 30 days. Groups were named C group or control, E group (massage, passive range of motion and neuromuscular electrical stimulation, H group (massage, passive range of motion and aquatic therapy in underwater treadmill and EH group (massage, passive range of motion, neuromuscular electrical stimulation and aquatic therapy in underwater treadmill. It was measured the degree of lameness, range motion, thigh circumference and range of serum creatine kinase (CK and lactate dehydrogenase (LDH. According to the results, it was possible to conclude that associated therapeutics modalities such as massage, passive range of motion of the joint, neuromuscular electrical stimulation and aquatic therapy by walking on underwater treadmill accelerate clinical recovery in dogs with induced muscle atrophy.

  13. Multisegmental cervical ossification of the posterior longitudinal ligament: Anterior vs posterior approach

    OpenAIRE

    Jain Subodh; Salunke Pravin; Vyas K; Behari Sanjay; Banerji Deepu; Jain Vijendra

    2005-01-01

    Aims : To determine the surgical approach in patients with multisegmental (four or more segments) OPLL of the cervical spine. Methods and Materials : Data of 27 patients who had undergone either an anterior (corpectomy with excision of OPLL and interbody fusion=14 patients) or posterior approach (laminectomy=12, laminoplasty=1 patient) for the multisegmental cervical OPLL was analyzed retrospectively. The patients in each group were statistically similar in respect to preoperative factors su...

  14. Simulating Cortical Feedback Modulation as Changes in Excitation and Inhibition in a Cortical Circuit Model.

    Science.gov (United States)

    Zagha, Edward; Murray, John D; McCormick, David A

    2016-01-01

    Cortical feedback pathways are hypothesized to distribute context-dependent signals during flexible behavior. Recent experimental work has attempted to understand the mechanisms by which cortical feedback inputs modulate their target regions. Within the mouse whisker sensorimotor system, cortical feedback stimulation modulates spontaneous activity and sensory responsiveness, leading to enhanced sensory representations. However, the cellular mechanisms underlying these effects are currently unknown. In this study we use a simplified neural circuit model, which includes two recurrent excitatory populations and global inhibition, to simulate cortical modulation. First, we demonstrate how changes in the strengths of excitation and inhibition alter the input-output processing responses of our model. Second, we compare these responses with experimental findings from cortical feedback stimulation. Our analyses predict that enhanced inhibition underlies the changes in spontaneous and sensory evoked activity observed experimentally. More generally, these analyses provide a framework for relating cellular and synaptic properties to emergent circuit function and dynamic modulation. PMID:27595137

  15. Simulating Cortical Feedback Modulation as Changes in Excitation and Inhibition in a Cortical Circuit Model

    Science.gov (United States)

    Murray, John D.; McCormick, David A.

    2016-01-01

    Abstract Cortical feedback pathways are hypothesized to distribute context-dependent signals during flexible behavior. Recent experimental work has attempted to understand the mechanisms by which cortical feedback inputs modulate their target regions. Within the mouse whisker sensorimotor system, cortical feedback stimulation modulates spontaneous activity and sensory responsiveness, leading to enhanced sensory representations. However, the cellular mechanisms underlying these effects are currently unknown. In this study we use a simplified neural circuit model, which includes two recurrent excitatory populations and global inhibition, to simulate cortical modulation. First, we demonstrate how changes in the strengths of excitation and inhibition alter the input–output processing responses of our model. Second, we compare these responses with experimental findings from cortical feedback stimulation. Our analyses predict that enhanced inhibition underlies the changes in spontaneous and sensory evoked activity observed experimentally. More generally, these analyses provide a framework for relating cellular and synaptic properties to emergent circuit function and dynamic modulation. PMID:27595137

  16. Glaucoma persistente secundário à injeção subtenoniana posterior de acetato de triancinolona (Kenalog®: relato de casos

    Directory of Open Access Journals (Sweden)

    Finamor Luciana Peixoto

    2003-01-01

    Full Text Available OBJETIVO: Descrever 3 casos de crianças submetidas à injeção subtenoniana posterior de acetato de triancinolona (Kenalog® 40mg para tratamento de uveíte intermediária, com desenvolvimento de glaucoma secundário refratário. MÉTODOS: Relato de caso. RESULTADOS: Três crianças com diagnóstico de uveíte intermediária, submetidas à injeção subtenoniana posterior de acetato de triancinolona para tratamento de inflamação vítrea crônica e/ou edema macular cistóide, desenvolveram glaucoma refratário e foram submetidos à excisão cirúrgica do corticóide de depósito e/ou cirurgia filtrante para controle da pressão intra-ocular (PIO. CONCLUSÃO: Corticóide de depósito periocular pode representar alto risco para desenvolvimento de glaucoma secundário, de difícil controle em crianças. Excisão cirúrgica do corticóide de depósito pode resultar em controle da PIO, porém, em alguns casos, a realização de cirurgia filtrante é necessária.

  17. Ephaptic coupling in cortical neurons

    Directory of Open Access Journals (Sweden)

    Costas Anastassiou

    2014-03-01

    Full Text Available The electrochemical processes that underlie neural function manifest themselves in ceaseless spatial and temporal fluctuations in the extracellular electric field. The local field potential (LFP, used to study neural interactions during various brain states, is regarded as an epiphenomenon of coordinated neural activity. Yet the extracellular field activity feeds back onto the electrical potential across the neuronal membrane via ephaptic coupling (Jefferys et al, Physiol Rev, 1995. The extent to which such ephaptic coupling alters the functioning of individual neurons and neural assemblies under physiological conditions has remained largely speculative despite recent advances (Ozen et al, JNeurosci, 2010; Fröhlich & McCormick, Neuron, 2010, Anastassiou et al, JNeurosci, 2010. To address this question we use a 12-pipette setup that allows independent positioning of each pipette under visual control with μm accuracy, with the flexibility of using an arbitrary number of these as patching, extracellularly stimulating or extracellular recording pipettes only a few μm away from the cell body of patched neurons (Anastassiou et al, Nat Neurosci, 2011. We stimulated in rat somatosensory cortical slices a variety of layer 5 neural types and recorded inside and outside their cell bodies while pharmacologically silencing synaptic transmission. Pyramidal cells couple to the extracellular field distinctly different from interneurons. Ephaptic coupling strength depends both on the field strength (as measured at the neuron soma as well as the spike-history of neurons. In particular, we find that ephaptic coupling strength depends both on the field strength (as measured at the cell body as well as the spike-history of neurons. How do such effects manifest themselves in vivo? We address this question through detailed large-scale simulations from thousands of biophysically realistic and interconnected neurons (Reimann, Anastassiou et al, Neuron, 2013 emulating

  18. Ultrasonic propagation in cortical bone mimics

    International Nuclear Information System (INIS)

    Understanding the velocity and attenuation characteristics of ultrasonic waves in cortical bone and bone mimics is important for studies of osteoporosis and fractures. Three complementary approaches have been used to help understand the ultrasound propagation in cortical bone and bone mimics immersed in water, which is used to simulate the surrounding tissue in vivo. The approaches used were Lamb wave propagation analysis, experimental measurement and two-dimensional (2D) finite difference modelling. First, the water loading effects on the free plate Lamb modes in acrylic and human cortical bone plates were examined. This theoretical study revealed that both the S0 and S1 mode velocity curves are significantly changed in acrylic: mode jumping occurs between the S0 and S1 dispersion curves. However, in human cortical bone plates, only the S1 mode curve is significantly altered by water loading, with the S0 mode exhibiting a small deviation from the unloaded curve. The Lamb wave theory predictions for velocity and attenuation were then tested experimentally on acrylic plates using an axial transmission technique. Finally, 2D finite difference numerical simulations of the experimental measurements were performed. The predictions from Lamb wave theory do not correspond to the measured and simulated first arrival signal (FAS) velocity and attenuation results for acrylic and human cortical bone plates obtained using the axial transmission technique, except in very thin plates

  19. Is posterior fusion necessary with laminectomy in the cervical spine?

    OpenAIRE

    McAllister, Beck D.; Rebholz, Brandon J.; Wang, Jeffery C.

    2012-01-01

    Background: Cervical decompressive laminectomy is a common procedure for addressing multilevel cervical spine pathology. The most common reasons for performing simultaneous posterior cervical fusion include the prevention of progressive postlaminectomy kyphotic deformity or other types of instability which can contribute to late neurological deterioration. Methods: The medical literature (Pub Med with MeSH) concerning cervical laminectomy, posterior cervical fusion, and complications of lamin...

  20. A STUDY OF POSTERIOR FOSSA MALFORMATIONS: MR IMAGING

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    Ravi

    2015-02-01

    Full Text Available AIMS AND OBJECTIVES: The aim of our study is to describe the imaging findings of various posterior fossa malformations and to evaluate the supratentorial abnormalities associated with posterior fossa malformations. MATERIALS AND METHODS: MR images of 30 patients wi th posterior fossa malformations detected in the department of Radiodiagnosis, BMCRI over a period of two years, from December 2012 to December 2014 were evaluated retrospectively. The various posterior fossa malformations were evaluated. Associated suprat entorial abnormalities were noted. RESULTS: 30 patients with posterior fossa malformations were included in the study. The age group of patients ranged from 1year to 53years. There were 18 males and 12 females. The various posterior fossa malformations det ected were Dandy Walker malformation (1 case, Dandy Walker variant (2 cases, mega cisterna magna (8 cases, arachnoid cysts (5 cases, Chiari 1 malformation (5 cases, Chairi 2 malformation (2 cases, Joubert malformation (1 case, lipoma (2 cases, verm ian and/or cerebellar hypoplasia without posterior fossa CSF collection or cyst (4 cases. Associated supratentorial abnormalities were seen in 8 cases . CONCLUSION: MRI is the imaging modality of choice in the evaluation of posterior fossa malformations. I t is very important to know the imaging findings of these malformations and to have knowledge about the various supratentorial and spinal abnormalities associated with them so as to provide an accurate diagnosis which is very essential for predicting the p rognosis and planning further management.

  1. MRI evaluation of the posterior meniscus root tear

    International Nuclear Information System (INIS)

    Objective: To determine the value of MRI for diagnosing the posterior meniscus root tear. Methods: MR examinations of 30 patients with tear of the posterior meniscus root confirmed by knee arthroscopies were retrospectively reviewed. Of the 30 patients, 17 with posterior medial meniscus root tear (MMRT) and 13 with posterior lateral meniscus root tear (LMRT). The diagnostic sensitivity of' MRI for the posterior meniscus root tear was analyzed. Fisher's exact test was used to compare the detection rate of MRI for MMRT with that for LMRT. Results: All 17 cases with MMRT and 9 cases out of 13 with LMRT were correctly diagnosed by MRI and the diagnostic sensitivity of MRI for the posterior meniscus root tear was 86.7% (26/30). The main MR appearance of the posterior meniscus root tear was distortion of the meniscal root, with its low signal replaced by abnormal high signal. The detection rate of MRI for MMRT (17/17) was significantly greater than that for LMRT (9/13) (P=0.026). The prevalence of MMRT associated with meniscus extrusion (15/17) was significantly greater than that of LMRT (6/13) (P=0.020), but the prevalence of MMRT associated with anterior cruciate ligament (ACL) injury (5/17) was significantly lower than that of LMRT (11/13) (P=0.004). Conclusion: MRI is a relatively good method for detection of posterior meniscus root tears and associated injuries. (authors)

  2. Fibrocellular contraction of a lamellar posterior corneal graft

    DEFF Research Database (Denmark)

    Hjortdal, Jesper; Ivarsen, Anders; Heegaard, Steffen

    2011-01-01

    To report a case of progressive fibrotic contraction of the posterior lamellar graft after initially successful Descemet's stripping automated endothelial keratoplasty (DSAEK).......To report a case of progressive fibrotic contraction of the posterior lamellar graft after initially successful Descemet's stripping automated endothelial keratoplasty (DSAEK)....

  3. Symptomatic Posterior Cruciate Ganglion Cyst Causing Impingement between Posterior Root of the Medial Meniscus and Anterior to the Posterior Cruciate Ligament

    OpenAIRE

    Joo, Yong Bum; Kim, Young Mo

    2012-01-01

    There are several reports of symptomatic ganglion cysts near the posterior cruciate ligament (PCL), but no reports of a symptomatic ganglion originating from the anterior aspect of the PCL in the deep recess between the posterior root of the medial meniscus and the PCL, bulging into the posteromedial joint space. In this report, we present the clinical features of a patient with a symptomatic ganglion cyst treated successfully by arthroscopic excision.

  4. Evaluation of cortical bone thickness of mandible with cone beam computed tomography for orthodontic mini implant installation

    Directory of Open Access Journals (Sweden)

    Seyed Hossein Moslemzade

    2014-07-01

    Full Text Available Background: Achieving maximum anchorage without movement of the teeth in anchorage unit has been a great challenge in orthodontics and the success of the treatment plan highly depends on it. In this case, using orthodontic mini-implants can make a huge difference. The objective of this retrospective study was to measure thickness of cortical bone at prospective mini-implant placement sites in mandible in order to understand stability aspects of mini-implant placement by using cone-beam computed tomography (CBCT images.Materials and Methods: Initial 3-dimensional images of 40 adult patients were studied. The cortical bone thickness was obtained at the alveolar processes from canine to second molar at 5 different vertical levels from the cementoenamel junction (CEJ. To determine the cortical bone thickness, tangent lines were drawn buccolingually to the roots in axial section and a third line was drawn from the middle of these two lines, and the cortical bone thickness was measured where the third line crossed the buccal cortex. Results: Mandibular and buccal cortical bone thicknesses were 0.79 to 2.49 mm, respectively. There was a statistically significant increase from the CEJ to the apex (P<0.001, while this increase was not statically significant at interdental area of teeth #3 and #4. Comparing the 4 mm section in all sites showed significant increase from anterior to posterior.Conclusion: Based on our results, the cortical bone thickness mostly follows a pattern and depends on the interradicular site rather than individual differences.  Key words: Cone-beam computed tomography; orthodontic anchorage procedures

  5. Cortical Reorganisation during a 30-Week Tinnitus Treatment Program.

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    Catherine M McMahon

    Full Text Available Subjective tinnitus is characterised by the conscious perception of a phantom sound. Previous studies have shown that individuals with chronic tinnitus have disrupted sound-evoked cortical tonotopic maps, time-shifted evoked auditory responses, and altered oscillatory cortical activity. The main objectives of this study were to: (i compare sound-evoked brain responses and cortical tonotopic maps in individuals with bilateral tinnitus and those without tinnitus; and (ii investigate whether changes in these sound-evoked responses occur with amelioration of the tinnitus percept during a 30-week tinnitus treatment program. Magnetoencephalography (MEG recordings of 12 bilateral tinnitus participants and 10 control normal-hearing subjects reporting no tinnitus were recorded at baseline, using 500 Hz, 1000 Hz, 2000 Hz, and 4000 Hz tones presented monaurally at 70 dBSPL through insert tube phones. For the tinnitus participants, MEG recordings were obtained at 5-, 10-, 20- and 30- week time points during tinnitus treatment. Results for the 500 Hz and 1000 Hz sources (where hearing thresholds were within normal limits for all participants showed that the tinnitus participants had a significantly larger and more anteriorly located source strengths when compared to the non-tinnitus participants. During the 30-week tinnitus treatment, the participants' 500 Hz and 1000 Hz source strengths remained higher than the non-tinnitus participants; however, the source locations shifted towards the direction recorded from the non-tinnitus control group. Further, in the left hemisphere, there was a time-shifted association between the trajectory of change of the individual's objective (source strength and anterior-posterior source location and subjective measures (using tinnitus reaction questionnaire, TRQ. The differences in source strength between the two groups suggest that individuals with tinnitus have enhanced central gain which is not significantly influenced by

  6. Cortical Reorganisation during a 30-Week Tinnitus Treatment Program.

    Science.gov (United States)

    McMahon, Catherine M; Ibrahim, Ronny K; Mathur, Ankit

    2016-01-01

    Subjective tinnitus is characterised by the conscious perception of a phantom sound. Previous studies have shown that individuals with chronic tinnitus have disrupted sound-evoked cortical tonotopic maps, time-shifted evoked auditory responses, and altered oscillatory cortical activity. The main objectives of this study were to: (i) compare sound-evoked brain responses and cortical tonotopic maps in individuals with bilateral tinnitus and those without tinnitus; and (ii) investigate whether changes in these sound-evoked responses occur with amelioration of the tinnitus percept during a 30-week tinnitus treatment program. Magnetoencephalography (MEG) recordings of 12 bilateral tinnitus participants and 10 control normal-hearing subjects reporting no tinnitus were recorded at baseline, using 500 Hz, 1000 Hz, 2000 Hz, and 4000 Hz tones presented monaurally at 70 dBSPL through insert tube phones. For the tinnitus participants, MEG recordings were obtained at 5-, 10-, 20- and 30- week time points during tinnitus treatment. Results for the 500 Hz and 1000 Hz sources (where hearing thresholds were within normal limits for all participants) showed that the tinnitus participants had a significantly larger and more anteriorly located source strengths when compared to the non-tinnitus participants. During the 30-week tinnitus treatment, the participants' 500 Hz and 1000 Hz source strengths remained higher than the non-tinnitus participants; however, the source locations shifted towards the direction recorded from the non-tinnitus control group. Further, in the left hemisphere, there was a time-shifted association between the trajectory of change of the individual's objective (source strength and anterior-posterior source location) and subjective measures (using tinnitus reaction questionnaire, TRQ). The differences in source strength between the two groups suggest that individuals with tinnitus have enhanced central gain which is not significantly influenced by the tinnitus

  7. Cortical Reorganisation during a 30-Week Tinnitus Treatment Program

    Science.gov (United States)

    McMahon, Catherine M.; Ibrahim, Ronny K.; Mathur, Ankit

    2016-01-01

    Subjective tinnitus is characterised by the conscious perception of a phantom sound. Previous studies have shown that individuals with chronic tinnitus have disrupted sound-evoked cortical tonotopic maps, time-shifted evoked auditory responses, and altered oscillatory cortical activity. The main objectives of this study were to: (i) compare sound-evoked brain responses and cortical tonotopic maps in individuals with bilateral tinnitus and those without tinnitus; and (ii) investigate whether changes in these sound-evoked responses occur with amelioration of the tinnitus percept during a 30-week tinnitus treatment program. Magnetoencephalography (MEG) recordings of 12 bilateral tinnitus participants and 10 control normal-hearing subjects reporting no tinnitus were recorded at baseline, using 500 Hz, 1000 Hz, 2000 Hz, and 4000 Hz tones presented monaurally at 70 dBSPL through insert tube phones. For the tinnitus participants, MEG recordings were obtained at 5-, 10-, 20- and 30- week time points during tinnitus treatment. Results for the 500 Hz and 1000 Hz sources (where hearing thresholds were within normal limits for all participants) showed that the tinnitus participants had a significantly larger and more anteriorly located source strengths when compared to the non-tinnitus participants. During the 30-week tinnitus treatment, the participants’ 500 Hz and 1000 Hz source strengths remained higher than the non-tinnitus participants; however, the source locations shifted towards the direction recorded from the non-tinnitus control group. Further, in the left hemisphere, there was a time-shifted association between the trajectory of change of the individual’s objective (source strength and anterior-posterior source location) and subjective measures (using tinnitus reaction questionnaire, TRQ). The differences in source strength between the two groups suggest that individuals with tinnitus have enhanced central gain which is not significantly influenced by the

  8. Posterior Corneal Surface Stability after Femtosecond Laser-Assisted Keratomileusis

    Directory of Open Access Journals (Sweden)

    Carlo Cagini

    2015-01-01

    Full Text Available The purpose of this study was to evaluate posterior corneal surface variation after femtosecond laser-assisted keratomileusis in patients with myopia and myopic astigmatism. Patients were evaluated by corneal tomography preoperatively and at 1, 6, and 12 months. We analyzed changes in the posterior corneal curvature, posterior corneal elevation, and anterior chamber depth. Moreover, we explored correlation between corneal ablation depth, residual corneal thickness, percentage of ablated corneal tissue, and preoperative corneal thickness. During follow-up, the posterior corneal surface did not have a significant forward corneal shift: no significant linear relationships emerged between the anterior displacement of the posterior corneal surface and corneal ablation depth, residual corneal thickness, or percentage of ablated corneal tissue.

  9. Preliminary Findings Show Maternal Hypothyroidism May Contribute to Abnormal Cortical Morphology in Offspring

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    Julieta E. Lischinsky

    2016-02-01

    Full Text Available In rodents, insufficient thyroid hormone (TH gestationally has adverse effects on cerebral cortex development. Comparable studies of humans examining how TH insufficiency affects cortical morphology are limited to children with congenital hypothyroidism or offspring of hypothyroxinemic women; effects on cortex of children born to women with clinically diagnosed hypothyroidism are not known. We studied archived MRI scans from 22 children aged 10 to 12 years born to women treated for preexisting or de novo hypothyroidism within pregnancy (HYPO and 24 similar age and sex controls from euthyroid women. FreeSurfer Image Analysis Suite software was used to measure cortical thickness (CT and a vertex-based approach served to compare HYPO versus control groups and Severe versus Mild HYPO subgroups as well as to perform regression analyses examining effects of trimester-specific maternal TSH on CT. Results showed that relative to controls, HYPO had multiple regions of both cortical thinning and thickening, which differed for left and right hemispheres. In HYPO, thinning was confined to medial and mid-lateral regions of each hemisphere and thickening to superior regions (primarily frontal of the left hemisphere and inferior regions (particularly occipital and temporal of the right. The Severe HYPO subgroup showed more thinning than Mild in frontal and temporal regions and more thickening in bilateral posterior and frontal regions. Maternal TSH values predicted degree of thinning and thickening within multiple brain regions, with the pattern and direction of correlations differing by trimester. Notably, some correlations remained when cases born to women with severe hypothyroidism were removed from the analyses suggesting mild variations of maternal TH may permanently affect offspring cortex. We conclude that maternal hypothyroidism during pregnancy has long-lasting manifestations on the cortical morphology of their offspring with specific effects

  10. Posterior Probability Matching and Human Perceptual Decision Making.

    Directory of Open Access Journals (Sweden)

    Richard F Murray

    2015-06-01

    Full Text Available Probability matching is a classic theory of decision making that was first developed in models of cognition. Posterior probability matching, a variant in which observers match their response probabilities to the posterior probability of each response being correct, is being used increasingly often in models of perception. However, little is known about whether posterior probability matching is consistent with the vast literature on vision and hearing that has developed within signal detection theory. Here we test posterior probability matching models using two tools from detection theory. First, we examine the models' performance in a two-pass experiment, where each block of trials is presented twice, and we measure the proportion of times that the model gives the same response twice to repeated stimuli. We show that at low performance levels, posterior probability matching models give highly inconsistent responses across repeated presentations of identical trials. We find that practised human observers are more consistent across repeated trials than these models predict, and we find some evidence that less practised observers more consistent as well. Second, we compare the performance of posterior probability matching models on a discrimination task to the performance of a theoretical ideal observer that achieves the best possible performance. We find that posterior probability matching is very inefficient at low-to-moderate performance levels, and that human observers can be more efficient than is ever possible according to posterior probability matching models. These findings support classic signal detection models, and rule out a broad class of posterior probability matching models for expert performance on perceptual tasks that range in complexity from contrast discrimination to symmetry detection. However, our findings leave open the possibility that inexperienced observers may show posterior probability matching behaviour, and our methods

  11. Gastroesophageal reflux disease correlation with posterior laryngitis

    Directory of Open Access Journals (Sweden)

    Dimitrijević Milovan

    2009-01-01

    Full Text Available Background/Aim. Over the last years numerous studies have been performed dealing with mutual relations among gastroesophageal reflux disease (GERD and numerous diseases of the upper airways. The aim of the present study was to establish possible causal relationship between GERD and posterior laryngitis (PL. Methods. The study included 103 patients with gastrointestinal complaints. Diagnostic procedure included a medical history, gastroscopy and laryngeal directoscopy. The obtained data processed using classic methods of the descriptive statistics, as well as Pearson's chi-square test, Student's t test, rank sum test and Fisher's parametric analysis of variance. Results. Out of the total number of 103 examined patients, 33 (32% were diagnosed with PL, while GERD was diagnosed in five of the examined patients all belonging to the PL group (15% of the patients with PL. In the remaining patients, PL was caused by other factors. All the patients with GERD had PL and globus sensation while 80% of GERD patients had prominent symptom of pain. Conclusion. The results of the study are indicative of the causal relationship between GERD and PL.

  12. New infectious etiologies for posterior uveitis.

    Science.gov (United States)

    Khairallah, Moncef; Kahloun, Rim; Ben Yahia, Salim; Jelliti, Bechir; Messaoud, Riadh

    2013-01-01

    Emergent and resurgent arthropod vector-borne diseases are major causes of systemic morbidity and death and expanding worldwide. Among them, viral and bacterial agents including West Nile virus, Dengue fever, Chikungunya, Rift Valley fever, and rickettsioses have been recently associated with an array of ocular manifestations. These include anterior uveitis, retinitis, chorioretinitis, retinal vasculitis and optic nerve involvement. Proper clinical diagnosis of any of these infectious diseases is based on epidemiological data, history, systemic symptoms and signs, and the pattern of ocular involvement. The diagnosis is usually confirmed by the detection of a specific antibody in serum. Ocular involvement associated with emergent infections usually has a self-limited course, but it can result in persistent visual impairment. There is currently no proven specific treatment for arboviral diseases, and therapy is mostly supportive. Vaccination for humans against these viruses is still in the research phase. Doxycycline is the treatment of choice for rickettsial diseases. Prevention, including public measures to reduce the number of mosquitoes and personal protection, remains the mainstay for arthropod vector disease control. Influenza A (H1N1) virus was responsible for a pandemic human influenza in 2009, and was recently associated with various posterior segment changes. PMID:23258387

  13. Posterior endoscopic discectomy: Results in 300 patients

    Directory of Open Access Journals (Sweden)

    Mohinder Kaushal

    2012-01-01

    Full Text Available Background: Posterior endoscopic discectomy is an established method for treatment of lumbar disc herniation. Many studies have not been reported in literature for lumbar discectomy by Destandau Endospine System. We report a series of 300 patients operated for lumbar dissectomy by Destandau Endospine system. Materials and Methods: A total of 300 patients suffering from lumbar disc herniations were operated between January 2002 and December 2008. All patients were operated as day care procedure. Technique comprised localization of symptomatic level followed by insertion of an endospine system devise through a 15 mm skin and fascial incision. Endoscopic discectomy is then carried out by conventional micro disc surgery instruments by minimal invasive route. The results were evaluated by Macnab′s criteria after a minimum followup of 12 months and maximum up to 24 months. Results: Based on modified Macnab′s criteria, 90% patients had excellent to good, 8% had fair, and 2% had poor results. The complications observed were discitis and dural tear in five patients each and nerve root injury in two patients. 90% patients were able to return to light and sedentary work with an average delay of 3 weeks and normal physical activities after 2 months. Conclusion: Edoscopic discectomy provides a safe and minimal access corridor for lumbar discectomy. The technique also allows early postoperative mobilization and faster return to work.

  14. Automatic quantification of posterior capsule opacification

    Science.gov (United States)

    Barman, Sarah A.; Uyyanonvara, Bunyarit; Boyce, James F.; Sanguinetti, Giorgia; Hollick, Emma J.; Meacock, William R.; Spalton, David J.; Paplinski, Andrew P.

    2000-06-01

    After Cataract surgery where a plastic implant lens is implanted into the eye to replace the natural lens, many patients suffer from cell growth across a membrane situated at the back of the lens which degrades their vision. The cell growth is known as Posterior Capsule Opacification (or PCO). It is important to be able to quantify PCO so that the effect of different implant lens types and surgical techniques may be evaluated. Initial results obtained using a neural network to detect PCO from implant lenses are compared to an established but less automated method of detection, which segments the images using texture segmentation in conjunction with co- occurrence matrices. Tests show that the established method performs well in clinical validation and repeatability trials. The requirement to use a neural network to analyze the implant lens images evolved from the analysis of over 1000 images using the established co-occurrence matrix segmentation method. The work shows that a method based on neural networks is a promising tool to automate the procedure of calculating PCO.

  15. The posterior glottis: structural and clinical considerations.

    Science.gov (United States)

    Kotby, M N; Kamal, E; El-Makhzangy, A; Nabil Khattab, A; Milad, P

    2012-11-01

    Despite the presence of a number of good publications during the past two decades, the posterior glottis (PG) is still not clearly appreciated in clinical laryngological practice. This study focuses on searching the literature to find out the present day awareness of the PG, as well as highlighting some of its clinical features. The investigation proceeds with two main sections: (1) critical analysis of the literature on the PG during the last 50 years (2) describing the clinical appearance and behavior of the PG in 100 normal subjects. Results of section 1 illustrate the limited awareness in the literature of the existence of PG as a distinct part of the human larynx. Results of section 2 illustrate some misconcepts related to the PG as inter-arytenoid pachydermia, change of voice with lesions in the PG. Discussion elaborates on the significance of the findings and attempts to clarify certain misconcepts about the PG, its structure, function, and clinical features. In the light of the data collected from the literature regarding the dimensions of the PG, a set of recommendations were proposed regarding the optimal sizes of the endotracheal tubes in both sexes. PMID:22614807

  16. Combined Anterior-Posterior Surgery Versus Posterior Surgery for Thoracolumbar Burst Fractures: A Systematic Review of the Literature

    NARCIS (Netherlands)

    P.P. Oprel (Pim); W.E. Tuinebreijer (Wim); P. Patka (Peter); D. den Hartog (Dennis)

    2010-01-01

    textabstractAbstract: Study Design: A systematic quantitative review of the literature. Objective: To compare combined anterior-posterior surgery versus posterior surgery for thoracolumbar fractures in order to identify better treatments. Summary of Background Data: Axial load of the anterior and mi

  17. Organizing principles of cortical layer 6

    Directory of Open Access Journals (Sweden)

    Farran Briggs

    2010-02-01

    Full Text Available Neurons in the deepest layer of mammalian cerebral cortex are morphologically and physiological diverse and are situated in a strategic position to modulate neuronal activity locally and in other structures. The variety of neuronal circuits within which layer 6 neurons participate differs across species and cortical regions. However even amidst this diversity, common organizational features emerge. Examination of the anatomical and physiological characteristics of different classes of layer 6 neuron, each specialized to participate in distinct circuits, provides insight into the functional contributions of layer 6 neurons toward cortical information processing.

  18. Cortical networks for visual self-recognition

    International Nuclear Information System (INIS)

    This paper briefly reviews recent developments regarding the brain mechanisms of visual self-recognition. A special cognitive mechanism for visual self-recognition has been postulated based on behavioral and neuropsychological evidence, but its neural substrate remains controversial. Recent functional imaging studies suggest that multiple cortical mechanisms play self-specific roles during visual self-recognition, reconciling the existing controversy. Respective roles for the left occipitotemporal, right parietal, and frontal cortices in symbolic, visuospatial, and conceptual aspects of self-representation have been proposed. (author)

  19. Evolution of mammalian sensorimotor cortex: Thalamic projections to parietal cortical areas in Monodelphis domestica

    Directory of Open Access Journals (Sweden)

    James Clinton Dooley

    2015-01-01

    Full Text Available The current experiments build upon previous studies designed to reveal the network of parietal cortical areas present in the common mammalian ancestor. Understanding this ancestral network is essential for highlighting the basic somatosensory circuitry present in all mammals, and how this basic plan was modified to generate species specific behaviors. Our animal model, the short-tailed opossum (Monodelphis domestica, is a South American marsupial that has been proposed to have a similar ecological niche and morphology to the earliest common mammalian ancestor. In this investigation, we injected retrograde neuroanatomical tracers into the face and body representations of primary somatosensory cortex (S1, the rostral and caudal somatosensory fields (SR and SC, as well as a multimodal region (MM. Projections from different architectonically defined thalamic nuclei were then quantified. Our results provide further evidence to support the hypothesized basic mammalian plan of thalamic projections to S1, with the lateral and medial ventral posterior thalamic nuclei (VPl and VPm projecting to S1 body and S1 face, respectively. Additional strong projections are from the medial division of posterior nucleus (Pom. SR receives projections from several midline nuclei, including the medial dorsal, ventral medial nucleus, and Pom. SC and MM show similar patterns of connectivity, with projections from the ventral anterior and ventral lateral nuclei, VPm and VPl, and the entire posterior nucleus (medial and lateral. Notably, MM is distinguished from SC by relatively dense projections from the dorsal division of the lateral geniculate nucleus and pulvinar. We discuss the finding that S1 of the short-tailed opossum has a similar pattern of projections as other marsupials and mammals, but also some distinct projections not present in other mammals. Further we provide additional support for a primitive posterior parietal cortex which receives input from multiple

  20. Mild cognitive impairment, poor episodic memory, and late-life depression are associated with cerebral cortical thinning and increased white matter hyperintensities

    Directory of Open Access Journals (Sweden)

    Motonobu Fujishima

    2014-11-01

    Full Text Available In various independent studies to date, cerebral cortical thickness and white matter hyperintensity (WMH volume have been associated with episodic memory, depression, and mild cognitive impairment (MCI. The aim of this study was to uncover variations in cortical thickness and WMH volume in association with episodic memory, depressive state, and the presence of MCI simultaneously in a single study population. The participants were 186 individuals with MCI (clinical dementia rating [CDR] of 0.5 and 136 healthy elderly controls (HCs; CDR of 0 drawn from two community-based cohort studies in northern Japan. We computed cerebral cortical thickness and WMH volume by using MR scans and statistically analyzed differences in these indices between HCs and MCI participants. We also assessed the associations of these indices with memory performance and depressive state in participants with MCI. Compared with HCs, MCI participants exhibited thinner cortices in the temporal and inferior parietal lobes and greater WMH volumes in the corona radiata and semioval center. In MCI participants, poor episodic memory was associated with thinner cortices in the left entorhinal region and increased WMH volume in the posterior periventricular regions. Compared with non-depressed MCI participants, depressed MCI participants showed reduced cortical thickness in the anterior medial temporal lobe and ambient gyrus adjacent to the amygdala bilaterally, as well as greater WMH volume as a percentage of the total intracranial volume (WMHr. A higher WMHr was associated with cortical thinning in the frontal, temporal, and parietal regions in MCI participants. These results demonstrate that episodic memory and depression are associated with both cortical thickness and WMH volume in MCI participants. Additional longitudinal studies are needed to clarify the dynamic associations and interactions among these indices.

  1. Operative techniques of anastomotic posterior urethroplasty for traumatic posterior urethral strictures

    Institute of Scientific and Technical Information of China (English)

    ZHOU Zhan-song; SONG Bo; JIN Xi-yu; XIONG En-qing; ZHANG Jia-hua

    2007-01-01

    Objective: To elucidate the details of operative technique of anastomotic posterior urethroplasty for traumatic posterior urethral strictures in attempt to offer a successful result.Methods: We reviewed the clinical data of 106 patients who had undergone anastomotic repair for posterior urethral strictures following traumatic pelvic fracture between 1979 and 2004. Patients' age ranged from 8 to 53 years (mean 27 years). Surgical repair was performed via perinea in 72 patients, modified transperineal repair in 5 and perineoabdominal repair in 29. Follow-up ranged from 1 to 23 years (mean 8 years).Results: Among the 77 patients treated by perineal approaches, 69 (95.8%) were successfully repaired and 27 out of the 29 patients (93.1%) who were repaired by perineoabdominal protocols were successful. The successful results have sustained as long as 23 years in some cases. Urinary incontinence did not happen in any patients while impotence occurred as a result of the anastomotic surgery.Conclusions: Three important skills or principles will ensure a successful outcome, namely complete excision of scar tissues, a completely normal mucosa ready for anastomosis at both ends of the urethra, and a tension-free anastomosis. When the urethral stricture is below 2.5 cm long, restoration of urethral continuity can be accomplished by a perineal procedure. If the stricture is over 2.5 cm long, a modified perineal or transpubic perineoabdominal procedure should be used. In the presence of a competent bladder neck, anastomotic surgery does not result in urinary incontinence. Impotence is usually related to the original trauma and rarely (5.7%) to urethroplasty.

  2. A isometricidade do ligamento cruzado posterior Isometry of the posterior cruciate ligament

    OpenAIRE

    Alexandre E. V. Kokron; Arnaldo J. Hernandez; Camanho, Gilberto L.; Marco M. Amatuzzi

    2001-01-01

    Trabalho de revisão bibliográfica referente à isometricidade do ligamento cruzado posterior. São avaliados doze artigos que estudam a isometricidade do ligamento, constatando que a maioria destes é concorde com a maior importância da inserção femoral na isometricidade e que existe uma linha ou área mais isométrica na inserção femoral, aproximadamente perpendicular ao teto da fossa intercondilar, localizada de 10 a 14mm da abertura anterior desta fossa.The authors review 12 studies about poste...

  3. CT findings of traumatic posterior hip dislocation after reduction

    Energy Technology Data Exchange (ETDEWEB)

    Moon, Sung Kyoung; Park, Ji Seon; Ryu, Kyung Nam; Jin, Wook [Kyung Hee University Medical Center, Seoul (Korea, Republic of); Jin Wook

    2008-06-15

    To evaluate the CT images of reduced hips after posterior hip dislocation and to propose specific diagnostic criteria based on the CT results. We retrospectively reviewed the CT findings on 18 reduced hips from 17 patients with radiographs and clinical histories of traumatic posterior hip dislocations by evaluating 18 corresponding CT scans for joint space asymmetry, intra-articular abnormalities (intra-articular fat obliteration, loose bodies, and joint effusion), changes in posterior soft tissue (capsule, muscles, and adjacent fat), the presence, and location of fractures (acetabulum and femoral head). All 18 hips (100%) showed posterior soft tissue changes. In total, 17 hips (94.4%) had intra-articular abnormalities and 15 hips (83.3%) had joint space asymmetries. In addition, 17 hips (94.4%) had fractures involving the acetabula (15 cases, 88.2%) the femoral head (13 cases, 76.5%), or on both sides (11 cases, 64.7%). The most frequent fracture location was in he posterior wall (13/15, 86.7%) of the acetabulum and in the anterior aspect (10/13, 76.9%) of the femoral head. Patients with a prior history of posterior hip dislocation showed specific CT findings after reduction, suggesting the possibility of previous posterior hip dislocations in patients.

  4. RELATIONSHIP OF TRANSVERSAL ASYMMETRIC FACE AND UNILATERAL POSTERIOR CROSSBITE

    Directory of Open Access Journals (Sweden)

    Indah Dwinursanty

    2006-04-01

    Full Text Available Unilateral posterior crossbite is commonly seen in mixed dentition, but it couldn’t be self corrected. If this condition is not treated properly, it could lead to asymmetric face. Asymmetric face with unilateral posterior crossbite could make the treatment process more difficult. The objective of this study is to find out the relationship between transversal skeletal asymmetry and unilateral posterior crossbite. Patients older than 13 years with skeletal asymmetric face, who had never undergone orthodontic treatment or facial surgery were selected. The sample consisted of 15 females and 6 males (15 – 32 years old. Anteroposterior cephalogram was used for determining the difference between right and left of antegonial and the deviation of menton. Criteria for asymmetry were more than 3 mm on Antegonial and 2 mm or more on Menton. Mid Sagital Reference (MSR was used as reference line. Unilateral posterior crossbite could be seen in the dental model. The data was analyzed using Mann Whitney test. It was revealed that from 21 samples, 38.1% was found to have unilateral posterior crossbite involving four posterior teeth. Conclusion: There is no relationship between transveral skeletal symmetry and unilateral posterior crossbite.

  5. Posterior Urethral Valves ; A Single Center Experience

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    Alireza Mirshemirani

    2013-10-01

    Full Text Available Objective: Posterior urethral valves (PUV are the most common cause of bladder outlet obstruction in infancy that impair renal and bladder function. This study was planned to evaluate and record the various clinical presentations and management, complications, and surgical management and long-term outcome of PUV.Methods: In a retrospective study, 98 patients who have been treated for PUV are evaluated in Mofid Children’s Hospital from January 2007 to December 2012. Detailed history taken and paraclinical examinations were performed in each patient and diagnosis was confirmed by voiding-cysto-urethrography (VCUG. PUV had been ablated in 62 patients by electric hook, and diversion was performed in 42 (42.85% cases. Data were analyzed by SPSS software version18.Findings: Totally 98 patients with mean age at diagnosis 62 (±13 days were included in this study. Fifty seven cases had been catheterized within one to 6 days of life (mean age one day, PUV was ablated in 62 patients by electric hook, and diversion was performed in 42 cases. The most common symptom in our group was dribbling poor stream 51% and urinary tract infection (UTI 40.8%. There was vesico-ureteral-reflux (VUR in 61.2%, and hydronephrosis in 82.6%. Most common associated anomaly was kidney anomalies (multicystic kidney disease and renal agenesis/dysplasia in 8 (8.2% patients. Twenty patients had prenatal diagnosis of PUV. Complication occurred in three (3.1% patients. Mortality occurred in 5 (5.1% patients. Mean follow-up period was 3.4±1.2 years (1.5 months to 5 years.Conclusion: Urinary drainage by feeding tube in early days of infancy, followed by valve ablation is the best treatment in PUV, and urinary diversion improves the outcome. VCUG is still the gold-standard imaging modality for documenting PUVs. The factors like renal dysplasia and UTI have their role in final outcome.

  6. An evaluation of Microleakage of Posterior Composites

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    Mohammadi N

    1999-12-01

    Full Text Available Polymerization contraction may produce defects in the composite - tooth bond. This may lead to bond failure and microleakage. The aim of this study was to reduce microleakage of posterior composites using different methods. 45 molar and premolars extracted teeth were choosen. The cavities were randomly assigned into 5 groups of 9. Box-shaped cavities were prepared on each side of proximal surfaces and restored by five different methods. Group 1 was filled by a light-cured composite and dentin bonding agents (DBAs with light curing from the occlusal area. Group 2 was filled by a light-cured {LC} composite and DBA, in addition the angle between the light source and occlusal area was 45 degree. After conditioning of teeth in-group 3, LC glass ionomer was placed on the gingival floor and then filled by a light-cured composite and DBA. In group 4, after conditioning, the teeth were lined by a LC glass ionomer and then self-cured composite was placed on gingival floor. This group was filled with LC composite. In Group 5 DBA was used followed by placing a self-curing composite on gingival floor and filled by LC composite. The teeth were subjected to 500 thermocycling (5°C and 55°C with dowel time 30 s and stored in 0.5% basic fushin for 24 hours. Dye penetration was evaluated by light microscope. The results were tested by Kruskat-Wallis one-way analysis of variance by rank. The comparison between treatment groups showed highly significant difference {P<0.0001. No significant difference was found between groups 3 versus 4 and groups 1,2,5 versus 3,4. Group 3 showed the least microleakage score. Therefore least microleakage was obtained by the group which used L C glass ionomer and DBA followed by filling a composite.

  7. Mapping gray matter volume and cortical thickness in Alzheimer's disease

    Science.gov (United States)

    Guo, Xiaojuan; Li, Ziyi; Chen, Kewei; Yao, Li; Wang, Zhiqun; Li, Kuncheng

    2010-03-01

    Gray matter volume and cortical thickness are two important indices widely used to detect neuropathological changes in brain structural magnetic resonance imaging. Using optimized voxel-based morphometry (VBM) protocol and surface-based cortical thickness measure, this study comprehensively investigated the regional changes in cortical gray matter volume and cortical thickness in Alzheimer's disease (AD). Thirteen patients with AD and fourteen age- and gender-matched healthy controls were included in this study. Results showed that voxel-based gray matter volume and cortical thickness reductions were highly correlated in the temporal lobe and its medial structure in AD. Moreover significant reduced cortical regions of gray matter volume were obviously more than that of cortical thickness. These findings suggest that gray matter volume and cortical thickness, as two important imaging markers, are effective indices for detecting the neuroanatomical alterations and help us understand the neuropathology from different views in AD.

  8. Prenatal Alcohol Exposure and Cortical Angiogenesis

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    J Gordon Millichap

    2013-02-01

    Full Text Available Researchers at Normandy University, and Rouen and Brest Universities, France studied the effects of prenatal alcohol exposure on the cortical microvascular and the action of alcohol, glutamate, and vascular endothelial growth factor A (VEGF on activity, plasticity, and survival of microvessels in mice.

  9. Prenatal Alcohol Exposure and Cortical Angiogenesis

    OpenAIRE

    J Gordon Millichap

    2013-01-01

    Researchers at Normandy University, and Rouen and Brest Universities, France studied the effects of prenatal alcohol exposure on the cortical microvascular and the action of alcohol, glutamate, and vascular endothelial growth factor A (VEGF) on activity, plasticity, and survival of microvessels in mice.

  10. Exploring the Nature of Cortical Recurrent Interactions

    Science.gov (United States)

    Morita, Kenji; Kalra, Rita; Aihara, Kazuyuki; Robinson, Hugh P. C.

    2011-09-01

    Fast rhythmic activity of neural population has been frequently observed in cortical circuits, and suggested to be associated with various cognitive functions including working memory and selective attention. However, precisely how recurrent synaptic interactions, that are prominent in these circuits, shape and/or modulate such population rhythm has not been fully elucidated. We have addressed this issue by combining electrophysiological and computational approaches.

  11. Cortical operation of the ventral striatal switchboard

    OpenAIRE

    Stuber, Garret D.

    2013-01-01

    How does the ventral striatum (VS) prioritize and process afferent input? In this issue, Calhoon and O’Donnell demonstrate that cortical projections to the VS can attenuate hippocampal and thalamic VS input, suggesting that the cortex can uniquely control VS circuit dynamics.

  12. Epileptogenicity of Cortical Dysplasias and Tumors

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    J Gordon Millichap

    2009-12-01

    Full Text Available The epileptogenic characteristic of focal cortical dysplasias and dysembryoplastic neuroepithelial tumors explored by depth electrodes and stereoelectroencephalography is quantified using an epileptogenicity index, in a study of 36 patients with focal drug-resistant epilepsy at Universite de la Mediterranee and other centers in Marseille and Rennes, France.

  13. Simplified Classification of Focal Cortical Dysplasia

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2002-09-01

    Full Text Available Sections of cortex from 52 of 224 (23% patients with cortical dysplasia, operated on for drug-resistant partial epilepsy, were retrospectively re-examined histologically at Niguarda Hospital, and Istituto Nazionale Neurologico ‘C. Besta’, Milan, Italy.

  14. Response variability in balanced cortical networks

    DEFF Research Database (Denmark)

    Lerchner, Alexander; Ursta, C.; Hertz, J.;

    2006-01-01

    We study the spike statistics of neurons in a network with dynamically balanced excitation and inhibition. Our model, intended to represent a generic cortical column, comprises randomly connected excitatory and inhibitory leaky integrate-and-fire neurons, driven by excitatory input from an external...

  15. Neuroimaging of malformation of cortical development

    International Nuclear Information System (INIS)

    Malformations of cortical development (MCD) are heterogeneous group of disease which result from disruption of 3 main stages of cortical development.The common clinical presentation is refractory epilepsy and or developmental delay. The aim of this paper is to describe and analyze magnetic resonance (MR) findings and to present protocol for examination. We analyze MR findings in 17 patients with MCD. The average age was 12,1 year (from 2 months - 57 years). The main indications from reference physician are epilepsy and developmental delay. In 12 patients 1.5T MR was performed, and in 5 - 0.5T. Subependymal heterotopias was found in 6 patients, focal cortical dysplasia - 3. polymicrogyria - 3, schizencephaly - 2, hemimegalencephaly -1, lizencephaly -1, tuberous sclerosis -1. The most common MCD are heterotopias, focal cortical dysplasia, polymicrogyria. schizencephaiy, pachygyria and lizencephaly. In our study the number of patients is not big enough to make a conclusion about frequency of the forms of MCD and our goal is to analyze MR findings which are not well studied in our country. MRI is the method of choice for diagnosis of MCD. The protocol should be different from routine brain protocol to interpret the images with good quality and not miss the pathology. Knowledge of MR findings in MCD would help for genetic counselling in some cases or can predict prognosis in some patients. (authors)

  16. Cortical Memory Mechanisms and Language Origins

    Science.gov (United States)

    Aboitiz, Francisco; Garcia, Ricardo R.; Bosman, Conrado; Brunetti, Enzo

    2006-01-01

    We have previously proposed that cortical auditory-vocal networks of the monkey brain can be partly homologized with language networks that participate in the phonological loop. In this paper, we suggest that other linguistic phenomena like semantic and syntactic processing also rely on the activation of transient memory networks, which can be…

  17. Mean field methods for cortical network dynamics

    DEFF Research Database (Denmark)

    Hertz, J.; Lerchner, Alexander; Ahmadi, M.

    2004-01-01

    We review the use of mean field theory for describing the dynamics of dense, randomly connected cortical circuits. For a simple network of excitatory and inhibitory leaky integrate- and-fire neurons, we can show how the firing irregularity, as measured by the Fano factor, increases with the...

  18. Surgical approaches to posterior polar cataract: a review

    OpenAIRE

    Vasavada, A. R.; Raj, S M; Vasavada, V; Shrivastav, S

    2012-01-01

    The aim of this study is to provide a comprehensive overview of surgical methods used in the emulsification of posterior polar cataracts (PPCs) that have been devised to minimize the risk of posterior capsule rupture (PCR) and its consequences. A Pubmed and Medline search of relevant literature on PPC was done. Only articles relevant to the treatment of PPC were included. The posterior capsule in eyes with PPC are known to have an abnormal adhesion to the polar opacity or a pre-existing weakn...

  19. Isolated Brainstem Involvement in Posterior Reversible Encephalopathy Syndrome

    Directory of Open Access Journals (Sweden)

    Tarkan Ergün

    2013-09-01

    Full Text Available Posterior reversible encephalopathy syndrome (PRES is a clinical and radiologic entity characterized by headache, variable mental status, epilepsy, visual disturbances, and typical transient changes in the posterior cerebral perfusion. Parieto-occipital region the most commonly involved site. Less commonly, brainstem, basal ganglia, and cerebellum are involved besides the supratentorial white matter areas. However, isolated brainstem involvement is very rare. We here present a case of isolated brainstem involvement in posterior reversible encephalopathy syndrome which was diagnosed by diffusion-weighted MR imaging.

  20. Anatomic Double-Bundle Posterior Cruciate Ligament Reconstruction.

    Science.gov (United States)

    Chahla, Jorge; Nitri, Marco; Civitarese, David; Dean, Chase S; Moulton, Samuel G; LaPrade, Robert F

    2016-02-01

    The posterior cruciate ligament (PCL) is known to be the main posterior stabilizer of the knee. Anatomic single-bundle PCL reconstruction, focusing on reconstruction of the larger anterolateral bundle, is the most commonly performed procedure. Because of the residual posterior and rotational tibial instability after the single-bundle procedure and the inability to restore the normal knee kinematics, an anatomic double-bundle PCL reconstruction has been proposed in an effort to re-create the native PCL footprint more closely and to restore normal knee kinematics. We detail our technique for an anatomic double-bundle PCL reconstruction using Achilles and anterior tibialis tendon allografts. PMID:27284530

  1. Cellular organization of cortical barrel columns is whisker-specific

    OpenAIRE

    Meyer, Hanno S.; Egger, Robert; Guest, Jason M.; Foerster, Rita; Reissl, Stefan; Oberlaender, Marcel

    2013-01-01

    Cortical columns are thought to be the elementary functional building blocks of sensory cortices. Here we show that the cellular architecture of cortical “barrel” columns in rodent somatosensory cortex is not stereotypic, but specific for each whisker on the animals’ snout. Our findings challenge the concepts underlying contemporary simulation efforts that build up large-scale network models of repeatedly occurring identical cortical circuits.

  2. Trajectories of cortical surface area and cortical volume maturation in normal brain development

    Directory of Open Access Journals (Sweden)

    Simon Ducharme

    2015-12-01

    Full Text Available This is a report of developmental trajectories of cortical surface area and cortical volume in the NIH MRI Study of Normal Brain Development. The quality-controlled sample included 384 individual typically-developing subjects with repeated scanning (1–3 per subject, total scans n=753 from 4.9 to 22.3 years of age. The best-fit model (cubic, quadratic, or first-order linear was identified at each vertex using mixed-effects models, with statistical correction for multiple comparisons using random field theory. Analyses were performed with and without controlling for total brain volume. These data are provided for reference and comparison with other databases. Further discussion and interpretation on cortical developmental trajectories can be found in the associated Ducharme et al.׳s article “Trajectories of cortical thickness maturation in normal brain development – the importance of quality control procedures” (Ducharme et al., 2015 [1].

  3. Variability in Cortical Representations of Speech Sound Perception

    Science.gov (United States)

    Boatman, Dana F.

    2007-01-01

    Recent brain mapping studies have provided new insights into the cortical systems that mediate human speech perception. Electrocortical stimulation mapping (ESM) is a brain mapping method that is used clinically to localize cortical functions in neurosurgical patients. Recent ESM studies have yielded new insights into the cortical systems that…

  4. Veia gástrica posterior: hipertensão porta Posterior gastric vein: portal hipertension

    Directory of Open Access Journals (Sweden)

    Alcino Lázaro da Silva

    1999-10-01

    Full Text Available A veia gástrica posterior não é muito citada nos livros de anatomia e nos trabalhos sobre hipertensão porta. Estudou-se sua anatomia, freqüência e desembocadura. Ela foi encontrada em 54% dos casos e, em 100%, desembocava na veia esplênica. Discute-se a vantagem ou não de sua ligadura ou preservação no tratamento cirúrgico da hipertensão porta.The posterior gastric vein has not been mentioned very often neither in anatomy textbooks nor in portal hypertension papers. The authors studied the anatomy, frequency and confluence of this vein because is a huge variety in the presentation of esophageal varices. Twenty-six adult preserved corpses (twenty females and six males had a wide abdominal incision allowing the dissection of the portal system, identifying the frequency and confluence of its tributaries, notably the posterior gastric vein. The portal vein, in all cases, was formed by the confluence of the superior mesenteric vein with the splenic vein and had a mean length of 6.4 cm. The splenic vein had a mean length of 6.5 cm. The left gastric vein was tributary of the portal vein in 50% of the cases and in 30% of the cases in the splenic vein. The right gastric vein had it's confluence to portal vein in 30 % of the cases and to the splenic vein in 4 %. The inferior mesenteric vein was tributary of the splenic vein in 54% of the cases and in the superior mesenteric vein in 46%. The left gastro-omental vein had its confluence to the splenic vein in 50% of the cases and to the inferior polar vein in 34 %. The middle colic vein had its confluence to superior mesenteric vein in 42% of the cases, to inferior mesenteric vein in 12% and to splenic vein in 8%. The posterior gastric vein was found in 54% of the corpses, and in all cases it was a tributary of the splenic vein, in retropancreatic position, coming from the esophageal-gastric junction. These findings agree with previous papers describing a prevalence of 60% of posterior gastric

  5. Perceptual learning of simple stimuli modifies stimulus representations in posterior inferior temporal cortex.

    Science.gov (United States)

    Adab, Hamed Zivari; Popivanov, Ivo D; Vanduffel, Wim; Vogels, Rufin

    2014-10-01

    Practicing simple visual detection and discrimination tasks improves performance, a signature of adult brain plasticity. The neural mechanisms that underlie these changes in performance are still unclear. Previously, we reported that practice in discriminating the orientation of noisy gratings (coarse orientation discrimination) increased the ability of single neurons in the early visual area V4 to discriminate the trained stimuli. Here, we ask whether practice in this task also changes the stimulus tuning properties of later visual cortical areas, despite the use of simple grating stimuli. To identify candidate areas, we used fMRI to map activations to noisy gratings in trained rhesus monkeys, revealing a region in the posterior inferior temporal (PIT) cortex. Subsequent single unit recordings in PIT showed that the degree of orientation selectivity was similar to that of area V4 and that the PIT neurons discriminated the trained orientations better than the untrained orientations. Unlike in previous single unit studies of perceptual learning in early visual cortex, more PIT neurons preferred trained compared with untrained orientations. The effects of training on the responses to the grating stimuli were also present when the animals were performing a difficult orthogonal task in which the grating stimuli were task-irrelevant, suggesting that the training effect does not need attention to be expressed. The PIT neurons could support orientation discrimination at low signal-to-noise levels. These findings suggest that extensive practice in discriminating simple grating stimuli not only affects early visual cortex but also changes the stimulus tuning of a late visual cortical area. PMID:24702452

  6. A semi-dominant mutation in the general splicing factor SF3a66 causes anterior-posterior axis reversal in one-cell stage C. elegans embryos.

    Directory of Open Access Journals (Sweden)

    Mohammad R Keikhaee

    Full Text Available Establishment of anterior-posterior polarity in one-cell stage Caenorhabditis elegans embryos depends in part on astral microtubules. As the zygote enters mitosis, these microtubules promote the establishment of a posterior pole by binding to and protecting a cytoplasmic pool of the posterior polarity protein PAR-2 from phosphorylation by the cortically localized anterior polarity protein PKC-3. Prior to activation of the sperm aster, the oocyte Meiosis I and II spindles assemble and function, usually at the future anterior pole, but these meiotic spindle microtubules fail to establish posterior polarity through PAR-2. Here we show that a semi-dominant mutation in the general splicing factor SF3a66 can lead to a reversed axis of AP polarity that depends on PAR-2 and possibly on close proximity of oocyte meiotic spindles with the cell cortex. One possible explanation is that reduced levels of PKC-3, due to a general splicing defect, can result in axis reversal due to a failure to prevent oocyte meiotic spindle microtubules from interfering with AP axis formation.

  7. Properties of bilateral spinocerebellar activation of cerebellar cortical neurons

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    Pontus eGeborek

    2014-10-01

    Full Text Available We aimed to explore the cerebellar cortical inputs from two spinocerebellar pathways, the spinal border cell-component of the ventral spinocerebellar tract (SBC-VSCT and the dorsal spinocerebellar tract (DSCT, respectively, in the sublobule C1 of the cerebellar posterior lobe. The two pathways were activated by electrical stimulation of the contralateral lateral funiculus (coLF and the ipsilateral LF (iLF at lower thoracic levels. Most granule cells in sublobule C1 did not respond at all but part of the granule cell population displayed high-intensity responses to either coLF or iLF stimulation. As a rule, Golgi cells and Purkinje cell simple spikes responded to input from both LFs, although Golgi cells could be more selective. In addition, a small population of granule cells responded to input from both the coLF and the iLF. However, in these cases, similarities in the temporal topography and magnitude of the responses suggested that the same axons were stimulated from the two LFs, i.e. that the axons of individual spinocerebellar neurons could be present in both funiculi. This was also confirmed for a population of spinal neurons located within known locations of SBC-VSCT neurons and dorsal horn DSCT neurons. We conclude that bilateral spinocerebellar responses can occur in cerebellar granule cells, but the VSCT and DSCT systems that provide the input can also be organized bilaterally. The implications for the traditional functional separation of VSCT and DSCT systems and the issue whether granule cells primarily integrate functionally similar information or not are discussed.

  8. CT of adult lumbar disc herniations mimicking posterior apophyseal ring fractures

    Energy Technology Data Exchange (ETDEWEB)

    Gomori, J.M. (Hadassah Univ. Hospital, Jerusalem (Israel). Dept. of Radiology); Floman, Y.; Liebergall, M. (Hadassah Univ. Hospital, Jerusalem (Israel). Dept. of Orthopedics)

    1991-10-01

    This report concerns 35 adult patients with lumbar or sciatic pain and axial CT findings reportedly associated with posterior apophyseal ring fractures. Review of the CT images suggested two pathophysiologic categories. (1) Posterior Schmorl - A posterior intravertebral disc herniation with posterior displacement of a fractured or remodelled vertebral margin. (2) Calcified subligamentous - Reactive annular and or posterior longitudinal ligament calcification at the periphery of a herniated disc with or without remodelling and anterior displacement of the posterior vertebral margin. (orig.).

  9. Functional topography of cardiovascular regulation along the rostrocaudal axis of the rat posterior insular cortex.

    Science.gov (United States)

    Marins, Fernanda Ribeiro; Limborço-Filho, Marcelo; Xavier, Carlos Henrique; Biancardi, Vinicia C; Vaz, Gisele C; Stern, Javier E; Oppenheimer, Stephen M; Fontes, Marco Antonio Peliky

    2016-04-01

    Cardiovascular (CV) representation has been identified within the insular cortex (IC) and a lateralization of function previously suggested. In order to further understand the role of IC on cardiovascular control, the present study compared the CV responses evoked by stimulation of N-metil-D-aspartate (NMDA) receptors in the right and left posterior IC at different rostrocaudal levels. Intracortical microinjections of NMDA were performed into the IC of male Wistar rats anaesthetized with urethane (1.4 g/kg) prepared for blood pressure, heart rate and renal sympathetic nerve activity. Gene expression of NMDA receptor subunits NR2A and NR2B in the IC was confirmed by RT-PCR. Immunofluorescence for the NMDA receptor NR1 subunit was demonstrated in the IC (coordinates anteroposterior (AP) +1.5, 0.0 and -1.5 mm). A cardiac sympathoinhibitory site was identified, more rostrally located than identified in previous studies. A site of sympathoexcitatory cardiac control was identified more caudal to this region in agreement with earlier work. Under the experimental conditions, no lateralization of cardiovascular function was identified with chemical stimulation eliciting the same responses from either left or right insular cortices. No tonic role of the insula on cardiovascular control was identified with the use of the NMDA antagonist, AP-5. Peri-insular microinjection of NMDA was without cardiovascular effect indicating the specificity of the insula as a cardiovascular regulatory site. The current study reveals a functional topography for autonomic cardiovascular control along the rostrocaudal axis of the posterior IC. PMID:26748663

  10. Ossificação do ligamento longitudional posterior: relato de caso Posterior longitudinal ligament ossification: case report

    OpenAIRE

    Oswaldo Inácio de Tella Jr; Marco Antonio Herculano; Manoel Antonio de Paiva Neto; Atílio Faedo Neto; João Francisco Crosera

    2006-01-01

    Ossificação do ligamento longitudinal posterior (OLLP) cervical é patologia rara em nosso meio que pode ser tratada por abordagem anterior ou posterior da coluna. Relatamos o caso de um homem japonês de 42 anos com paraparesia progressiva e TC e RM comprovando o diagnóstico de OLLLP, submetido a corpectomia anterior com artrodese. A fisiopatologia desta entesopatia, prevalência racial, quadro clínico, características radiológicas e opções do procedimento cirúrgico são revistos.Posterior longi...

  11. Restoring cortical connectivity directionality and synchronization is essential to treating disorder of consciousness.

    Science.gov (United States)

    León-Carrión, Jose; León-Dominguez, Umberto; Halper, James; Pollonini, Luca; Zouridakis, George; Domínguez-Morales, Maria Del Rosario

    2014-01-01

    The design of neurorehabilitation therapy to treat subjects with altered consciousness provides opportunities and challenges to professionals involved with the care for these severely ill patients. While there is an increased interest in determining methods to restore consciousness in these patients, the process is complex and challenging, due in part to the diverse aetiology of these states of consciousness, and also to the intricate cerebral connectivity involved in their treatment. The present case study examines a patient who showed signs of emergence from the vegetative state after neurorehabilitation using The Combined Method Therapy (CMT). In this case, neurorehabilitation therapy was applied simultaneously with pharmacological treatment, stimulation, and neuroimaging techniques to help adjust drug dosage. The results of this study suggest that this combined approach to treatment promoted connectivity among posterior and anterior cortical regions aiding emergence from the vegetative state. PMID:24025059

  12. Posterior tibial tendon rupture—a brief report

    OpenAIRE

    Wootton, J. R.

    1990-01-01

    This brief report highlights the rarity of a posterior tibial tendon rupture, the problem of a progressive painful pes planus if the diagnosis is missed, and full return to sporting activities if treated early by surgical repair.

  13. Convergence rates of posterior distributions for Brownian semimartingale models

    NARCIS (Netherlands)

    F.H. van der Meulen; A.W. van der Vaart; J.H. van Zanten

    2006-01-01

    Key words and Phrases: Bayesian estimation, Continuous semimartingale, Dirichlet process, Hellinger distance, Infinite dimensional model, Rate of convergence, Wavelets. We consider the asymptotic behavior of posterior distributions based on continuous observations from a Brownian semimartingale mode

  14. Vitrectorhexis versus forceps posterior capsulorhexis in pediatric cataract surgery

    Directory of Open Access Journals (Sweden)

    Lav Kochgaway

    2013-01-01

    Full Text Available This study was done to compare the results of posterior continuous curvilinear capsulorhexis created using forceps with those created using vitrector in eyes suffering from congenital cataract. Vitrectorhexis term was first used by Wilson et al in 1999. [1] Fifty eyes with congenital and developmental cataract were included in this study. The posterior capsulorhexis was created using utrata forceps in 17 eyes or through a vitrector in 33 eyes. Forceps capsulorhexis was performed before IOL implantation, while vitrectorhexis was performed after IOL implantation in the bag. The results of both the surgery were compared using the following criteria: incidence of extension of rhexis, ability to achieve posterior rhexis of appropriate size, ability to implant the IOL in the bag, the surgical time, and learning curve. Vitrectorhexis after IOL implantation was an easy to learn alternative to manual posterior continuous curvilinear capsulorhexis in pediatric cataract surgery. It was more predictable and reproducible, with a short learning curve and lesser surgical time.

  15. Outcomes of Surgery for Posterior Polar Cataract Using Torsional Ultrasound

    Directory of Open Access Journals (Sweden)

    Selçuk Sızmaz

    2013-10-01

    Full Text Available Purpose: The aim of this study is to report outcomes of surgery for posterior polar cataract using torsional ultrasound. Material and Method: Medical records of 26 eyes of 21 consecutive patients with posterior polar cataract who had cataract surgery using the torsional phacoemulsification were evaluated retrospectively. The surgical procedure used, phacoemulsification parameters, intraoperative complications, and postoperative visual outcome were recorded. Results: Of the 26 eyes, 24 (92.3% had small to medium posterior polar opacity. Two eyes had large opacity. All surgeries were performed using the torsional handpiece. Posterior capsule rupture occurred in 4 (15.3% eyes. The mean visual acuity improved significantly after surgery (p<0.001. The postoperative visual acuity was worse than 20/20 in 5 eyes. The cause of the low acuity was amblyopia. Discussion: Successful surgical results and good visual outcome can be achieved with phacoemulsification using the torsional handpiece. (Turk J Ophthalmol 2013; 43: 345-7

  16. Aneurysms of the posterior cerebral artery in children

    International Nuclear Information System (INIS)

    Two cases of aneurysms of the posterior cerebral artery, diagnosed by CT and confirmed angiographically, are reported. In the first case, the aneurysm was discovered fortuitously. The second began with intracerebral haemorrhage. A review of the literature is reported. (orig.)

  17. Distal posterior tibial artery pseudoaneurysm after fracture calcaneous

    OpenAIRE

    Dey, Subhajeet; Das, Anjan K.; Dey, Rubi

    2008-01-01

    Here we report a case of pseudoaneurysm of distal posterior tibial artery following closed fracture of calcaneous. Association of pseudoaneurysm of posterior tibial artery with fracture of calcaneous is extremely uncommon. It is always suggested that pseudoaneurysm be treated by reconstruction, but here we present the case treated by ligation, obliteration and excision as it was situated distally and the plantar arch circulation was maintained. The purpose of this case report is to bring atte...

  18. Posterior cruciate ligament's tibial insertions: topographic anatomy and morphometric study

    OpenAIRE

    Julio Cesar Gali; Hector Campora de Sousa Oliveira; Bruno Cesar Bracher Lisboa; Bruno DiSerio Dias; Fabiana de Godoy Casimiro; Edie Benedito Caetano

    2013-01-01

    OBJECTIVE: To provide anatomical and morphometric basis of the posterior cruciate ligament's tibial insertions in order to assist the creation of anatomical tibial tunnels, in the ligament surgical reconstruction. MATERIAL AND METHODS: The topographic anatomy and morphometry of the posterior cruciate ligament's anterolateral and posteromedial bundles' tibial insertions were analyzed in 24 anatomical knee pieces. The pieces were photographed by a digital camera and the images obtained wer...

  19. Absent posterior tibial artery in a case with clubfoot

    OpenAIRE

    Bursali, Aysegul; Yurdoglu, Cihangir

    2004-01-01

    Absence of the posterior tibial artery is extremely rare. Complete absence of the posterior tibial artery associated with clubfoot was first reported in 1991. As far as we concern, our case is the second. For this reason we built a discussion over our case and related literature. We discuss that a vascular factor may contribute to the etiology of clubfoot and the importance of vascular malformations are emphasized in aspect of surgical dissection.

  20. Free posterior tibial flap reconstruction for hypopharyngeal squamous cell carcinoma

    OpenAIRE

    Fei CHEN; Liu, Jun; Wang, Lihong; Lv, Dan; Zhu, Yuanzhi; Wu, Qi; Li, Guojun; Zheng, Hongliang; Tao, Xiaofeng

    2014-01-01

    Objectives The aim of this article was to determine outcomes in patients with squamous cell carcinoma of the hypopharynx (SCCHP) in whom the free posterior tibial flap was used for primary reconstruction of hypopharynx defects after cancer resection. Subjects and methods Between August 2009 and February 2012, 10 patients with SCCHP underwent posterior tibial flap reconstruction for hypopharynx defects. The corresponding clinical data were retrospectively collected and analyzed. Results Despit...

  1. Absent posterior semicircular canal: HRCT feature of Waardenburg syndrome

    OpenAIRE

    Sandeep M Mahajan; Manish Pithwa; Apeksha Chavan; Deepti Pimple

    2012-01-01

    Absence of posterior semicircular canal is a rare condition, having been reported with only a few syndromes such as Waardenburg syndrome (WS), Alagellie, CHARGE, and Goldenhaar syndromes. We report a 12- year old male with bilateral absent posterior semicircular canals. These phenotypic characteristics of the patient favored the diagnosis of WS. WS is a rare autosomal dominant condition characterized by sensorineural hearing loss, in conjunction with pigmentary abnormalities and defects of th...

  2. Erupted complex odontoma of the posterior maxilla: A rarity.

    Science.gov (United States)

    Verma, Sonika; Arul, A Sri Kennath J; Arul, A Sri Sennath J; Chitra, S

    2015-08-01

    Complex odontomas, hamartomas of aborted tooth development, mainly occur in posterior part of the mandible and rarely erupt into the oral cavity. The spontaneous eruption may be associated with pain, inflammation of adjacent soft tissues or recurrent infection. The present case of complex odontoma is of particular interest due to its apparent eruption in the maxillary posterior segment, its association with agenesis of the second molar and impacted third molar; with the lesion being completely asymptomatic. PMID:26604611

  3. Posterior consistency in linear models under shrinkage priors

    CERN Document Server

    Armagan, Artin; Lee, Jaeyong; Bajwa, Waheed U

    2011-01-01

    We investigate posterior consistency in linear models with a diverging number of parameters. We first propose a parameter-free multivariate generalized double Pareto distribution as a default prior choice that preserves some of the desired characteristics of a joint double exponential distribution with multivariate Cauchy-like tails. We give sufficient conditions for consistency when $p/n\\rightarrow 0$ and then investigate the behavior of the posterior under normal, double exponential and multivariate generalized double Pareto priors.

  4. Isolated posterior high ankle sprain: a report of three cases.

    Science.gov (United States)

    Botchu, Rajesh; Allen, Patricia; Rennie, Winston J

    2013-12-01

    High ankle sprains are difficult to diagnose and account for 10% of all ankle sprains. A high index of suspicion is essential for diagnosis. High ankle sprains are managed symptomatically, with prolonged rehabilitation. The posterior inferior tibiofibular ligament is the strongest syndesmotic ligament; isolated injury of it is rare. We present 3 cases of isolated posterior high ankle sprain and discuss the relevant anatomy, mechanism of injury, and management. PMID:24366808

  5. Complications of Posterior Vertebral Resection for Spinal Deformity

    OpenAIRE

    Kim, Sung-Soo; Cho, Beom-Cheol; Kim, Jin-Hyok; Lim, Dong-Ju; Park, Ji-Yong; Lee, Beom-Jung; Suk, Se-Il

    2012-01-01

    Study Design Retrospective study. Purpose To evaluate the incidence and risk factors of complications following posterior vertebral resection (PVR) for spinal deformity. Methods A review of 233 patients treated with PVR at one institution over a nine-year period (1997 to 2005) was performed. The average age was 33.5 years. Complications were assessed in terms of surgical techniques (posterior vertebral column resection [PVCR] and decancellation osteotomy) and etiologies of deformity. Results ...

  6. Ganglion Cyst of the Posterior Longitudinal Ligament Causing Lumbar Radiculopathy

    OpenAIRE

    Cho, Sung-Min; Rhee, Woo-Tack; Lee, Sang-Youl; Lee, Sang-Bok

    2010-01-01

    Degenerated conditions such as herniated disc or spinal stenosis are common etiologies of lumbar radiculopathy. Less common etiologies include spinal extradural cyst such as synovial cysts and ganglion cysts. Ganglion cyst of the posterior longitudinal ligament (PLL) of the spine is a rare entity that can result in classical sciatica. Posterior longitudinal ligament cyst has no continuity with the facet joint and has no epithelial lining. Two young male patients presented with unilateral scia...

  7. Visual and eye movement functions of the posterior parietal cortex

    OpenAIRE

    Andersen, Richard A.

    1989-01-01

    Lesions of the posterior parietal area in humans produce interesting spatial-perceptual and spatial-behavioral deficits. Among the more important deficits observed are loss of spatial memories, problems representing spatial relations in models or drawings, disturbances in the spatial distribution of attention, and the inability to localize visual targets. Posterior parietal lesions in nonhuman primates also produce visual spatial deficits not unlike those found in humans. Mountcastle and his ...

  8. Cytology and Functionally Correlated Circuits of Human Posterior Cingulate Areas

    OpenAIRE

    Vogt, Brent A.; Vogt, Leslie; Laureys, Steven

    2005-01-01

    Human posterior cingulate cortex (PCC) and retrosplenial cortex (RSC) form the posterior cingulate gyrus, however, monkey connection and human imaging studies suggest that PCC area 23 is not uniform and atlases mislocate RSC. We histologically assessed these regions in 6 postmortem cases, plotted a flat map, and characterized differences in dorsal (d) and ventral (v) area 23. Subsequently, functional connectivity of histologically guided regions of interest (ROI) were assessed in 163 [18F]flu...

  9. Ureteral injury after posterior lumbar discectomy with interbody screw fixation

    OpenAIRE

    Pillai, Sunil Bhaskara; Hegde, Padmaraj; Venkatesh, Giridhar; Iyyan, Bhalaguru

    2013-01-01

    We report a case of iatrogenic ureteral injury secondary to L5 laminectomy and microdiscectomy with L5–S1 bone graft with posterior lumbar interbodyfusion using presacral cancellous screw fixation, managed by initial ureteral stent placement and subsequent Boari bladder flap repair. A 33-year-old woman underwent L5 laminectomy and microdiscectomy with L5–S1 bone graft with posterior lumbar interbody fusion using presacral cancellous screw fixation. On postoperative day 10, she developed lower...

  10. Bilateral locked posterior shoulder dislocation in a footballer.

    OpenAIRE

    Ryan, J; Whitten, M

    1997-01-01

    Posterior dislocation of the shoulder is an uncommon injury, accounting for between 2% and 4% of all shoulder dislocations. It occurs most frequently in patients following convulsions or direct anterior force to the shoulder. It is a particularly uncommon injury in sport. This paper reports an unusual case of bilateal locked posteriorly dislocated shoulders in a previously healthy young man who fell while playing football.

  11. Optimizing tooth form with direct posterior composite restorations.

    Science.gov (United States)

    Raghu, Ramya; Srinivasan, Raghu

    2011-10-01

    Advances in material sciences and technology have provided today's clinicians the strategies to transform the mechanistic approach of operative dentistry into a biologic philosophy. In the last three decades, composite resins have gone from being just an esthetically pleasing way of restoring Class III and Class IV cavities to become the universal material for both anterior and posterior situations as they closely mimic the natural esthetics while restoring the form of the human dentition. In order to enhance their success, clinicians have to rethink their protocol instead of applying the same restorative concepts and principles practiced with metallic restorations. Paralleling the evolution of posterior composite resin materials, cavity designs, restorative techniques and armamentarium have also developed rapidly to successfully employ composite resins in Class II situations. Most of the earlier problems with posterior composites such as poor wear resistance, polymerization shrinkage, postoperative sensitivity, predictable bonding to dentin, etc., have been overcome to a major extent. However, the clinically relevant aspect of achieving tight contacts in Class II situations has challenged clinicians the most. This paper reviews the evolution of techniques and recent developments in achieving predictable contacts with posterior composites. A Medline search was performed for articles on "direct posterior composite contacts." The keywords used were "contacts and contours of posterior composites." The reference list of each article was manually checked for additional articles of relevance. PMID:22144797

  12. Optimizing tooth form with direct posterior composite restorations

    Directory of Open Access Journals (Sweden)

    Ramya Raghu

    2011-01-01

    Full Text Available Advances in material sciences and technology have provided today′s clinicians the strategies to transform the mechanistic approach of operative dentistry into a biologic philosophy. In the last three decades, composite resins have gone from being just an esthetically pleasing way of restoring Class III and Class IV cavities to become the universal material for both anterior and posterior situations as they closely mimic the natural esthetics while restoring the form of the human dentition. In order to enhance their success, clinicians have to rethink their protocol instead of applying the same restorative concepts and principles practiced with metallic restorations. Paralleling the evolution of posterior composite resin materials, cavity designs, restorative techniques and armamentarium have also developed rapidly to successfully employ composite resins in Class II situations. Most of the earlier problems with posterior composites such as poor wear resistance, polymerization shrinkage, postoperative sensitivity, predictable bonding to dentin, etc., have been overcome to a major extent. However, the clinically relevant aspect of achieving tight contacts in Class II situations has challenged clinicians the most. This paper reviews the evolution of techniques and recent developments in achieving predictable contacts with posterior composites. A Medline search was performed for articles on ′′direct posterior composite contacts.′′ The keywords used were ′′contacts and contours of posterior composites.′′ The reference list of each article was manually checked for additional articles of relevance.

  13. Modelling Human Cortical Network in Real Brain Space

    Institute of Scientific and Technical Information of China (English)

    ZHAO Qing-Bai; FENG Hong-Bo; TANG Yi-Yuan

    2007-01-01

    Highly specific structural organization is of great significance in the topology of cortical networks.We introduce a human cortical network model.taking the specific cortical structure into account,in which nodes are brain sites placed in the actual positions of cerebral cortex and the establishment of edges depends on the spatial path length rather than the linear distance.The resulting network exhibits the essential features of cortical connectivity,properties of small-world networks and multiple clusters structure.Additionally.assortative mixing is also found in this roodel.All of these findings may be attributed to the spedtic cortical architecture.

  14. Linear and Curvilinear Trajectories of Cortical Loss with Advancing Age and Disease Duration in Parkinson’s Disease

    Science.gov (United States)

    Claassen, Daniel O.; Dobolyi, David G.; Isaacs, David A.; Roman, Olivia C.; Herb, Joshua; Wylie, Scott A.; Neimat, Joseph S.; Donahue, Manus J.; Hedera, Peter; Zald, David H.; Landman, Bennett A.; Bowman, Aaron B.; Dawant, Benoit M.; Rane, Swati

    2016-01-01

    Advancing age and disease duration both contribute to cortical thinning in Parkinson’s disease (PD), but the pathological interactions between them are poorly described. This study aims to distinguish patterns of cortical decline determined by advancing age and disease duration in PD. A convenience cohort of 177 consecutive PD patients, identified at the Vanderbilt University Movement Disorders Clinic as part of a clinical evaluation for Deep Brain Stimulation (age: M= 62.0, SD 9.3), completed a standardized clinical assessment, along with structural brain Magnetic Resonance Imaging scan. Age and gender matched controls (n=53) were obtained from the Alzheimer Disease Neuroimaging Initiative and Progressive Parkinson’s Marker Initiative (age: M= 63.4, SD 12.2). Estimated changes in cortical thickness were modeled with advancing age, disease duration, and their interaction. The best-fitting model, linear or curvilinear (2nd, or 3rd order natural spline), was defined using the minimum Akaike Information Criterion, and illustrated on a 3-dimensional brain. Three curvilinear patterns of cortical thinning were identified: early decline, late decline, and early-stable-late. In contrast to healthy controls, the best-fit model for age related changes in PD is curvilinear (early decline), particularly in frontal and precuneus regions. With advancing disease duration, a curvilinear model depicts accelerating decline in the occipital cortex. A significant interaction between advancing age and disease duration is evident in frontal, motor, and posterior parietal areas. Study results support the hypothesis that advancing age and disease duration differentially affect regional cortical thickness and display regional dependent linear and curvilinear patterns of thinning. PMID:27330836

  15. One step arthroscopically assisted Latarjet and posterior bone-block, for recurrent posterior instability and anterior traumatic dislocation

    Directory of Open Access Journals (Sweden)

    Riccardo D′Ambrosi

    2015-01-01

    Full Text Available This case presents the challenges of the surgical management for a patient with a history of recurrent posterior shoulder instability and subsequently traumatic anterior dislocation. The patient was already on the waiting list for an arthroscopic posterior stabilization with anchors, when a car accident caused an additional anterior shoulder dislocation. This traumatic anterior dislocation created a bone loss with a glenoid fracture and aggravated the preexisting posterior instability. In order to address both problems, we decided to perform an arthroscopically assisted Latarjet procedure for anterior instability and to stabilize with a bone graft for posterior instability. To our best knowledge, this type of surgical procedure has so far never been reported in the literature. The purpose of this report is to present the surgical technique and to outline the decision making process.

  16. Genetic animal models of malformations of cortical development and epilepsy.

    Science.gov (United States)

    Wong, Michael; Roper, Steven N

    2016-02-15

    Malformations of cortical development constitute a variety of pathological brain abnormalities that commonly cause severe, medically-refractory epilepsy, including focal lesions, such as focal cortical dysplasia, heterotopias, and tubers of tuberous sclerosis complex, and diffuse malformations, such as lissencephaly. Although some cortical malformations result from environmental insults during cortical development in utero, genetic factors are increasingly recognized as primary pathogenic factors across the entire spectrum of malformations. Genes implicated in causing different cortical malformations are involved in a variety of physiological functions, but many are focused on regulation of cell proliferation, differentiation, and neuronal migration. Advances in molecular genetic methods have allowed the engineering of increasingly sophisticated animal models of cortical malformations and associated epilepsy. These animal models have identified some common mechanistic themes shared by a number of different cortical malformations, but also revealed the diversity and complexity of cellular and molecular mechanisms that lead to the development of the pathological lesions and resulting epileptogenesis. PMID:25911067

  17. Left cortical specialization for visual letter strings predicts rudimentary knowledge of letter-sound association in preschoolers.

    Science.gov (United States)

    Lochy, Aliette; Van Reybroeck, Marie; Rossion, Bruno

    2016-07-26

    Reading, one of the most important cultural inventions of human society, critically depends on posterior brain areas of the left hemisphere in proficient adult readers. In children, this left hemispheric cortical specialization for letter strings is typically detected only after approximately 1 y of formal schooling and reading acquisition. Here, we recorded scalp electrophysiological (EEG) brain responses in 5-y-old (n = 40) prereaders presented with letter strings appearing every five items in rapid streams of pseudofonts (6 items per second). Within 2 min of recording only, letter strings evoked a robust specific response over the left occipito-temporal cortex at the predefined frequency of 1.2 Hz (i.e., 6 Hz/5). Interindividual differences in the amplitude of this electrophysiological response are significantly related to letter knowledge, a preschool predictor of later reading ability. These results point to the high potential of this rapidly collected behavior-free measure to assess reading ability in developmental populations. These findings were replicated in a second experiment (n = 26 preschool children), where familiar symbols and line drawings of objects evoked right-lateralized and bilaterally specific responses, respectively, showing the specificity of the early left hemispheric dominance for letter strings. Collectively, these findings indicate that limited knowledge of print in young children, before formal education, is sufficient to develop specialized left lateralized neuronal circuits, thereby pointing to an early onset and rapid impact of left hemispheric reentrant sound mapping on posterior cortical development. PMID:27402739

  18. Transcranial Direct Current Stimulation Modulates Cortical Neuronal Activity in Alzheimer's Disease

    Science.gov (United States)

    Marceglia, Sara; Mrakic-Sposta, Simona; Rosa, Manuela; Ferrucci, Roberta; Mameli, Francesca; Vergari, Maurizio; Arlotti, Mattia; Ruggiero, Fabiana; Scarpini, Elio; Galimberti, Daniela; Barbieri, Sergio; Priori, Alberto

    2016-01-01

    Quantitative electroencephalography (qEEG) showed that Alzheimer's disease (AD) is characterized by increased theta power, decreased alpha and beta power, and decreased coherence in the alpha and theta band in posterior regions. These abnormalities are thought to be associated with functional disconnections among cortical areas, death of cortical neurons, axonal pathology, and cholinergic deficits. Since transcranial Direct Current Stimulation (tDCS) over the temporo-parietal area is thought to have beneficial effects in patients with AD, in this study we aimed to investigate whether tDCS benefits are related to tDCS-induced changes in cortical activity, as represented by qEEG. A weak anodal current (1.5 mA, 15 min) was delivered bilaterally over the temporal-parietal lobe to seven subjects with probable AD (Mini-Mental State Examination, MMSE score >20). EEG (21 electrodes, 10–20 international system) was recorded for 5 min with eyes closed before (baseline, t0) and 30 min after anodal and cathodal tDCS ended (t1). At the same time points, patients performed a Word Recognition Task (WRT) to assess working memory functions. The spectral power and the inter- and intra-hemispheric EEG coherence in different frequency bands (e.g., low frequencies, including delta and theta; high frequencies, including alpha and beta) were calculated for each subject at t0 and t1. tDCS-induced changes in EEG neurophysiological markers were correlated with the performance of patients at the WRT. At baseline, qEEG features in AD patients confirmed that the decreased high frequency power was correlated with lower MMSE. After anodal tDCS, we observed an increase in the high-frequency power in the temporo-parietal area and an increase in the temporo-parieto-occipital coherence that correlated with the improvement at the WRT. In addition, cathodal tDCS produced a non-specific effect of decreased theta power all over the scalp that was not correlated with the clinical observation at the WRT

  19. X-linked spinal and bulbar muscular atrophy (Kennedy's disease with long-term electrophysiological evaluation: case report Atrofia muscular bulbo-espinal ligada ao cromossomo X (doença de Kennedy com seguimento eletrofisiológico de longo prazo: relato de caso

    Directory of Open Access Journals (Sweden)

    João Aris Kouyoumdjian

    2005-03-01

    Full Text Available X-linked spinal and bulbar muscular atrophy or Kennedy's disease is an adult-onset motor neuronopathy caused by a CAG repeat expansion within the first exon of an androgen receptor gene. We report the case of a 66-year-old man, previously diagnosed with motor neuron disease (MND, who presented acute and reversible left vocal fold (dysphonia and pharyngeal paresis, followed by a slowly progressive weakness and also bouts of weakness, wasting and fasciculation on tongue, masseter, face, pharyngeal, and some proximal more than distal upper limb muscles, associated to bilateral hand tremor and mild gynecomastia. There were 5 electroneuromyography exams between 1989 and 2003 that revealed chronic reinnervation, some fasciculations (less than clinically observed and rare fibrillation potentials, and slowly progressive sensory nerve action potentials (SNAP abnormality, leading to absent/low amplitude potentials. PCR techniques of DNA analysis showed an abnormal number of CAG repeats, found to be 44 (normal 11-34. Our case revealed an acute and asymmetric clinical presentation related to bulbar motoneurons; low amplitude/absent SNAP with mild asymmetry; a sub-clinical or subtle involvement of proximal/distal muscles of both upper and lower limbs; and a probable evolution with bouts of acute dennervation, followed by an efficient reinnervation.Atrofia muscular bulbo-espinal ligada ao cromossomo X (doença de Kennedy é uma neuronopatia motora em adultos causada por expansões na repetição CAG no gene do receptor andrógeno. Neste relato, descreve-se o caso de homem de 66 anos, com diagnóstico prévio de doença do neurônio motor (DNM que apresentou quadro agudo e reversível de paresia de prega vocal (disfonia e de músculos faríngeos à esquerda; posteriormente seguiram-se surtos de fraqueza lentamente progressiva, atrofia e fasciculações em língua, masseter, face, faringe e membros superiores predominantemente proximal, associada a tremor

  20. Unified statistical approach to cortical thickness analysis.

    Science.gov (United States)

    Chung, Moo K; Robbins, Steve; Evans, Alan C

    2005-01-01

    This paper presents a unified image processing and analysis framework for cortical thickness in characterizing a clinical population. The emphasis is placed on the development of data smoothing and analysis framework. The human brain cortex is a highly convoluted surface. Due to the convoluted non-Euclidean surface geometry, data smoothing and analysis on the cortex are inherently difficult. When measurements lie on a curved surface, it is natural to assign kernel smoothing weights based on the geodesic distance along the surface rather than the Euclidean distance. We present a new data smoothing framework that address this problem implicitly without actually computing the geodesic distance and present its statistical properties. Afterwards, the statistical inference is based on the random field theory based multiple comparison correction. As an illustration, we have applied the method in detecting the regions of abnormal cortical thickness in 16 high functioning autistic children. PMID:17354731

  1. Visuomotor transformations: early cortical mechanisms of reaching.

    Science.gov (United States)

    Caminiti, R; Ferraina, S; Mayer, A B

    1998-12-01

    Recent studies of visually guided reaching in monkeys support the hypothesis that the visuomotor transformations underlying arm movements to spatial targets involve a parallel mechanism that simultaneously engages functionally related frontal and parietal areas linked by reciprocal cortico-cortical connections. The neurons in these areas possess similar combinations of response properties. The multimodal combinatorial properties of these neurons and the gradient architecture of the parietofrontal network emerge as a potential substrate to link the different sensory and motor signals that arise during reaching behavior into common hybrid reference frames. This convergent combinatorial process is evident at early stages of visual information processing in the occipito-parietal cortex, suggesting the existence of re-entrant motor influences on cortical areas once believed to have only visual functions. PMID:9914239

  2. Reduced cortical thickness in gambling disorder

    DEFF Research Database (Denmark)

    Grant, Jon E; Odlaug, Brian Lawrence; Chamberlain, Samuel R

    2015-01-01

    Gambling disorder has recently been recognized as a prototype 'behavioral addiction' by virtue of its inclusion in the DSM-5 category of 'Substance-Related and Addictive Disorders.' Despite its newly acquired status and prevalence rate of 1-3 % globally, relatively little is known regarding the...... neurobiology of this disorder. The aim of this study was to explore cortical morphometry in untreated gambling disorder, for the first time. Subjects with gambling disorder (N = 16) free from current psychotropic medication or psychiatric comorbidities, and healthy controls (N = 17), were entered into the...... study and undertook magnetic resonance imaging (3T MRI). Cortical thickness was quantified using automated segmentation techniques (FreeSurfer), and group differences were identified using permutation cluster analysis, with stringent correction for multiple comparisons. Gambling disorder was associated...

  3. Cortical Thickness Changes Associated with Photoparoxysmal Response

    DEFF Research Database (Denmark)

    Hanganu, Alexandru; Groppa, Stanislav A; Deuschl, Günther;

    2014-01-01

    Photoparoxysmal response (PPR) is an EEG trait of spike and spike-wave discharges in response to photic stimulation that is closely linked to idiopathic generalized epilepsy (IGE). In our previous studies we showed that PPR is associated with functional alterations in the occipital and frontal...... compared these groups with a group of PPR-negative-healthy-controls (HC, n = 17; 15.3 ± 3.6 years; 6 males). Our results revealed an increase of cortical thickness in the occipital, frontal and parietal cortices bilaterally in PPR-positive-subjects in comparison to HC. Moreover PPR...... the occipital lobe, frontoparietal regions and temporal lobe, which also show functional changes associated with PPR. Patients with epilepsy present changes in the temporal lobe and supplementary motor area....

  4. Optimizing sound features for cortical neurons.

    Science.gov (United States)

    deCharms, R C; Blake, D T; Merzenich, M M

    1998-05-29

    The brain's cerebral cortex decomposes visual images into information about oriented edges, direction and velocity information, and color. How does the cortex decompose perceived sounds? A reverse correlation technique demonstrates that neurons in the primary auditory cortex of the awake primate have complex patterns of sound-feature selectivity that indicate sensitivity to stimulus edges in frequency or in time, stimulus transitions in frequency or intensity, and feature conjunctions. This allows the creation of classes of stimuli matched to the processing characteristics of auditory cortical neurons. Stimuli designed for a particular neuron's preferred feature pattern can drive that neuron with higher sustained firing rates than have typically been recorded with simple stimuli. These data suggest that the cortex decomposes an auditory scene into component parts using a feature-processing system reminiscent of that used for the cortical decomposition of visual images. PMID:9603734

  5. Functional cortical mapping of scale illusion

    International Nuclear Information System (INIS)

    We have studied cortical activation using 1.5 T fMRI during 'Scale Illusion', a kind of auditory illusion, in which subjects perceive smooth melodies while listening to dichotic irregular pitch sequences consisting of scale tones, in repeated phrases composed of eight tones. Four male and four female subjects listened to different stimuli, that including illusion-inducing tone sequence, monaural tone sequence and perceived pitch sequence with a control of white noises delivered to the right and left ears in random order. 32 scans with a repetition time (TR) 3 s Between 3 s interval for each type of the four stimuli were performed. In BOLD signals, activation was observed in the prefrontal and temporal cortices, parietal lobule and occipital areas by first-level group analysis. However, there existed large intersubject variability such that systematic tendency of the activation was not clear. The study will be continued to obtain larger number of subjects for group analysis. (author)

  6. Localization of cortical areas activated by thinking

    DEFF Research Database (Denmark)

    Roland, P E; Friberg, L

    1985-01-01

    These experiments were undertaken to demonstrate that pure mental activity, thinking, increases the cerebral blood flow and that different types of thinking increase the regional cerebral blood flow (rCBF) in different cortical areas. As a first approach, thinking was defined as brain work in the...... they started at their front door and then walked alternatively to the left or the right each time they reached a corner. The rCBF increased only in homotypical cortical areas during thinking. The areas in the superior prefrontal cortex increased their rCBF equivalently during the three types of...... thinking. In the remaining parts of the prefrontal cortex there were multifocal increases of rCBF. The localizations and intensities of these rCBF increases depended on the type of internal operation occurring. The rCBF increased bilaterally in the angular cortex during 50-3 thinking. The rCBF increased in...

  7. Cortical reorganization in children with cochlear implants.

    Science.gov (United States)

    Gilley, Phillip M; Sharma, Anu; Dorman, Michael F

    2008-11-01

    Congenital deafness leads to atypical organization of the auditory nervous system. However, the extent to which auditory pathways reorganize during deafness is not well understood. We recorded cortical auditory evoked potentials in normal hearing children and in congenitally deaf children fitted with cochlear implants. High-density EEG and source modeling revealed principal activity from auditory cortex in normal hearing and early implanted children. However, children implanted after a critical period of seven years revealed activity from parietotemporal cortex in response to auditory stimulation, demonstrating reorganized cortical pathways. Reorganization of central auditory pathways is limited by the age at which implantation occurs, and may help explain the benefits and limitations of implantation in congenitally deaf children. PMID:18775684

  8. Mean field methods for cortical network dynamics

    DEFF Research Database (Denmark)

    Hertz, J.; Lerchner, Alexander; Ahmadi, M.

    2004-01-01

    We review the use of mean field theory for describing the dynamics of dense, randomly connected cortical circuits. For a simple network of excitatory and inhibitory leaky integrate- and-fire neurons, we can show how the firing irregularity, as measured by the Fano factor, increases with the stren......We review the use of mean field theory for describing the dynamics of dense, randomly connected cortical circuits. For a simple network of excitatory and inhibitory leaky integrate- and-fire neurons, we can show how the firing irregularity, as measured by the Fano factor, increases...... with the strength of the synapses in the network and with the value to which the membrane potential is reset after a spike. Generalizing the model to include conductance-based synapses gives insight into the connection between the firing statistics and the high- conductance state observed experimentally in visual...

  9. Whose Cortical Column Would that Be?

    OpenAIRE

    Nuno Miguel M Amorim Da Costa

    2010-01-01

    The cortical column has been an invaluable concept to explain the functional organization of the neocortex. While this idea was born out of experiments that cleverly combined electrophysiological recordings with anatomy, no one has ‘seen’ the anatomy of a column. All we know is that when we record through the cortex of primates, ungulates, and carnivores in a trajectory perpendicular to its surface there is a remarkable constancy in the receptive field properties of the neurons re...

  10. Reelin' in Genes for Cortical Dysplasia

    OpenAIRE

    Crino, Peter B.

    2001-01-01

    Malformations of cortical development are a broad family of disorders that are characterized by abnormal cytoarchitecture of the cerebral cortex and a high association with epilepsy. In recent years positional cloning strategies have been implemented to identify several distinct gene mutations that are responsible for developmental brain malformations. The defined functional roles of proteins encoded by these genes have provided pivotal insights into the cellular mechanisms of brain developme...

  11. Cortical subnetwork dynamics during human language tasks.

    Science.gov (United States)

    Collard, Maxwell J; Fifer, Matthew S; Benz, Heather L; McMullen, David P; Wang, Yujing; Milsap, Griffin W; Korzeniewska, Anna; Crone, Nathan E

    2016-07-15

    Language tasks require the coordinated activation of multiple subnetworks-groups of related cortical interactions involved in specific components of task processing. Although electrocorticography (ECoG) has sufficient temporal and spatial resolution to capture the dynamics of event-related interactions between cortical sites, it is difficult to decompose these complex spatiotemporal patterns into functionally discrete subnetworks without explicit knowledge of each subnetwork's timing. We hypothesized that subnetworks corresponding to distinct components of task-related processing could be identified as groups of interactions with co-varying strengths. In this study, five subjects implanted with ECoG grids over language areas performed word repetition and picture naming. We estimated the interaction strength between each pair of electrodes during each task using a time-varying dynamic Bayesian network (tvDBN) model constructed from the power of high gamma (70-110Hz) activity, a surrogate for population firing rates. We then reduced the dimensionality of this model using principal component analysis (PCA) to identify groups of interactions with co-varying strengths, which we term functional network components (FNCs). This data-driven technique estimates both the weight of each interaction's contribution to a particular subnetwork, and the temporal profile of each subnetwork's activation during the task. We found FNCs with temporal and anatomical features consistent with articulatory preparation in both tasks, and with auditory and visual processing in the word repetition and picture naming tasks, respectively. These FNCs were highly consistent between subjects with similar electrode placement, and were robust enough to be characterized in single trials. Furthermore, the interaction patterns uncovered by FNC analysis correlated well with recent literature suggesting important functional-anatomical distinctions between processing external and self-produced speech. Our

  12. Guidance cue for cortical radial migration discovered

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    @@ The regulatory mechanism for neuronal migration in the developing cortex is a major unsolved problem in developmental neurobiology. It is generally accepted that the migration of newborn pyramidal neurons from the ventricular zone toward upper cortical layers is guided by radial glial fibers in the developing cortex, and that the laminar structure of the cortex is formed through regulated attachment and detachment of migrating neurons with radial glial fibers.

  13. Elastic plastic damage laws for cortical bone

    OpenAIRE

    Garcia, David; Curnier, Alain; Zysset, Philippe

    2007-01-01

    Motivated by applications in orthopaedic and maxillo-facial surgery, the mechanical behaviour of cortical bone tissue in cyclic overloads at physiological strain rates is investigated. The emphasis is on the development of appropriate constitutive laws that faithfully reproduce the loading, unloading, and reloading sequence observed during experimental in vitro uniaxial testing. To this end, the models include three distinct modes of evolution, namely a linear elastic mode due to bone cohesio...

  14. Elastic plastic damage laws for cortical bone

    OpenAIRE

    Garcia, David

    2006-01-01

    Motivated by applications in orthopaedic and maxillo-facial surgery, the mechanical behaviour of cortical bone tissue in cyclic overloads at physiological strain rates is investigated. The emphasis is on the development of appropriate constitutive laws that faithfully reproduce the loading, unloading, and reloading sequence observed during experimental in vitro uniaxial testing. To this end, the models include three distinct modes of evolution, namely a linear elastic mode due to bone cohesio...

  15. Epilepsy, Acquired Aphasia with Focal Cortical Dysplasia

    Directory of Open Access Journals (Sweden)

    Girija A.S

    1999-01-01

    Full Text Available A six year old boy having complex partial seizures with secondary generalization of four months duration developing isolated expressive dysphasia, later progressing to global aphasia is being reported. His awake EEG showed a left temporal spike wave discharge and sleep EEG showed continuous spike and ware discharges. MR imaging demonstrated focal cortical dysplasia in the left frontal and opercular region, a combination that has not been reported earlier.

  16. Cortical Plasticity Induced by Inhibitory Neuron Transplantation

    OpenAIRE

    Southwell, Derek G.; Froemke, Robert C.; Alvarez-Buylla, Arturo; Stryker, Michael P.; Gandhi, Sunil P.

    2010-01-01

    Critical periods are times of pronounced brain plasticity. During a critical period in the postnatal development of the visual cortex, the occlusion of one eye triggers a rapid reorganization of neuronal responses, a process known as ocular dominance plasticity. We have shown that the transplantation of inhibitory neurons induces ocular dominance plasticity after the critical period. Transplanted inhibitory neurons receive excitatory synapses, make inhibitory synapses onto host cortical neuro...

  17. Cortical 3D Face Recognition Framework

    OpenAIRE

    J.M.F. Rodrigues; Lam, Roberto Célio Lau; du Buf, J. M. H.

    2011-01-01

    Empirical studies concerning face recognition suggest that faces may be stored in memory by a few canonical representations. In cortical area V1 exist double-opponent colour blobs, also simple, complex and end-stopped cells which provide input for a multiscale line/edge representation, keypoints for dynamic routing and saliency maps for Focus-of-Attention. All these combined allow us to segregate faces. Events of different facial views are stored in memory and combined in order to identify th...

  18. Atrofia de neurônios do plexo mientérico do íleo de ratos submetidos à intensa carência de proteínas=Atrophy of myenteric neurons in the ileum of rats submitted to severe protein deficiency

    Directory of Open Access Journals (Sweden)

    Débora de Mello Goncales Sant'Ana

    2012-04-01

    Full Text Available Objetivou-se avaliar os efeitos da oferta de uma dieta contendo 4% de proteínas para ratos adultos, quanto aos aspectos morfométricos do plexo mientérico do íleo. Vinte animais foram distribuídos aleatoriamente em dois grupos: Controle (n = 10 que receberam ração comercial com 26% de proteína e Experimental (n = 10 alimentados com ração com teor proteico reduzido para 4%, durante 90 dias. Neurônios do plexo mientérico do íleo presentes em preparados totais foram evidenciados por intermédio da técnica de Giemsa e da NADH-diaforase. Tanto a população neuronal total, assim como a subpopulação NADH-diaforase positiva sofreram atrofia com redução da área do pericário, do núcleo e do citoplasma.The effects of a 4%-protein diet in adult rats with respect to the morphometric aspects of the myenteric plexus in the ileum were assessed. Twenty animals were randomly divided into two groups: Control Group (n = 10, which received 26%-protein chow, and Experimental Group (n = 10, which received 4%-protein chow for 90 days. Neurons in the myenteric plexus in the ileum in whole mount were evidenced through Giemsa and NADH-diaphorase techniques. The overall neuronal population as well as the subpopulation positive for NADH diaphorase presented atrophy, with a reduction of the perikaryon, nucleus and cytoplasm.

  19. Nonfluent/Agrammatic PPA with In-Vivo Cortical Amyloidosis and Pick’s Disease Pathology

    Directory of Open Access Journals (Sweden)

    Francesca Caso

    2013-01-01

    Full Text Available The role of biomarkers in predicting pathological findings in the frontotemporal dementia (FTD clinical spectrum disorders is still being explored. We present comprehensive, prospective longitudinal data for a 66 year old, right-handed female who met current criteria for the nonfluent/agrammatic variant of primary progressive aphasia (nfvPPA. She first presented with a 3-year history of progressive speech and language impairment mainly characterized by severe apraxia of speech. Neuropsychological and general motor functions remained relatively spared throughout the clinical course. Voxel-based morphometry (VBM showed selective cortical atrophy of the left posterior inferior frontal gyrus (IFG and underlying insula that worsened over time, extending along the left premotor strip. Five years after her first evaluation, she developed mild memory impairment and underwent PET-FDG and PiB scans that showed left frontal hypometabolism and cortical amyloidosis. Three years later (11 years from first symptom, post-mortem histopathological evaluation revealed Pick's disease, with severe degeneration of left IFG, mid-insula, and precentral gyrus. Alzheimer’s disease (AD (CERAD frequent/Braak Stage V was also detected. This patient demonstrates that biomarkers indicating brain amyloidosis should not be considered conclusive evidence that AD pathology accounts for a typical FTD clinical/anatomical syndrome.

  20. Computational modeling of epidural cortical stimulation

    Science.gov (United States)

    Wongsarnpigoon, Amorn; Grill, Warren M.

    2008-12-01

    Epidural cortical stimulation (ECS) is a developing therapy to treat neurological disorders. However, it is not clear how the cortical anatomy or the polarity and position of the electrode affects current flow and neural activation in the cortex. We developed a 3D computational model simulating ECS over the precentral gyrus. With the electrode placed directly above the gyrus, about half of the stimulus current flowed through the crown of the gyrus while current density was low along the banks deep in the sulci. Beneath the electrode, neurons oriented perpendicular to the cortical surface were depolarized by anodic stimulation, and neurons oriented parallel to the boundary were depolarized by cathodic stimulation. Activation was localized to the crown of the gyrus, and neurons on the banks deep in the sulci were not polarized. During regulated voltage stimulation, the magnitude of the activating function was inversely proportional to the thickness of the CSF and dura. During regulated current stimulation, the activating function was not sensitive to the thickness of the dura but was slightly more sensitive than during regulated voltage stimulation to the thickness of the CSF. Varying the width of the gyrus and the position of the electrode altered the distribution of the activating function due to changes in the orientation of the neurons beneath the electrode. Bipolar stimulation, although often used in clinical practice, reduced spatial selectivity as well as selectivity for neuron orientation.

  1. Posterior transodontoid fixation: A new fixation (Kotil technique

    Directory of Open Access Journals (Sweden)

    Kadir Kotil

    2011-01-01

    Full Text Available Anterior odontoid screw fixation or posterior C1-2 fusion techniques are routinely used in the treatment of Type II odontoid fractures, but these techniques may be inadequate in some types of odontoid fractures. In this new technique (Kotil technique, through a posterior bilateral approach, transarticular screw fixation was performed at the non-dominant vertebral artery (VA side and posterior transodontoid fixation technique was performed at the dominant VA side. C1-2 complex fusion was aimed with unilateral transarticular fixation and odontoid fixation with posterior transodontoid screw fixation. Cervical spinal computed tomography (CT of a 40-year-old male patient involved in a motor vehicle accident revealed an anteriorly dislocated Type II oblique dens fracture, not reducible by closed traction. Before the operation, the patient was found to have a dominant right VA with Doppler ultrasound. He was operated through a posterior approach. At first, transarticular screw fixation was performed at the non-dominant (left side, and then fixation of the odontoid fracture was achieved by directing the contralateral screw (supplemental screw medially and toward the apex. Cancellous autograft was scattered for fusion without the need for structural bone graft or wiring. Postoperative cervical spinal CT of the patient revealed that stabilization was maintained with transarticular screw fixation and reduction and fixation of the odontoid process was achieved completely by posterior transodontoid screw fixation. The patient is at the sixth month of follow-up and complete fusion has developed. With this new surgical technique, C1-2 fusion is maintained with transarticular screw fixation and odontoid process is fixed by concomitant contralateral posterior transodontoid screw (supplemental screw fixation; thus, this technique both stabilizes the C1-2 complex and fixes the odontoid process and the corpus in atypical odontoid fractures, appearing as an

  2. Influence of the cortical midline structures on moral emotion and motivation in moral decision-making.

    Science.gov (United States)

    Han, Hyemin; Chen, Jingyuan; Jeong, Changwoo; Glover, Gary H

    2016-04-01

    The present study aims to examine the relationship between the cortical midline structures (CMS), which have been regarded to be associated with selfhood, and moral decision making processes at the neural level. Traditional moral psychological studies have suggested the role of moral self as the moderator of moral cognition, so activity of moral self would present at the neural level. The present study examined the interaction between the CMS and other moral-related regions by conducting psycho-physiological interaction analysis of functional images acquired while 16 subjects were solving moral dilemmas. Furthermore, we performed Granger causality analysis to demonstrate the direction of influences between activities in the regions in moral decision-making. We first demonstrate there are significant positive interactions between two central CMS seed regions-i.e., the medial prefrontal cortex (MPFC) and posterior cingulate cortex (PCC)-and brain regions associated with moral functioning including the cerebellum, brainstem, midbrain, dorsolateral prefrontal cortex, orbitofrontal cortex and anterior insula (AI); on the other hand, the posterior insula (PI) showed significant negative interaction with the seed regions. Second, several significant Granger causality was found from CMS to insula regions particularly under the moral-personal condition. Furthermore, significant dominant influence from the AI to PI was reported. Moral psychological implications of these findings are discussed. The present study demonstrated the significant interaction and influence between the CMS and morality-related regions while subject were solving moral dilemmas. Given that, activity in the CMS is significantly involved in human moral functioning. PMID:26772629

  3. Modulation of Cortical Oscillations by Low-Frequency Direct Cortical Stimulation Is State-Dependent.

    Science.gov (United States)

    Alagapan, Sankaraleengam; Schmidt, Stephen L; Lefebvre, Jérémie; Hadar, Eldad; Shin, Hae Won; Frӧhlich, Flavio

    2016-03-01

    Cortical oscillations play a fundamental role in organizing large-scale functional brain networks. Noninvasive brain stimulation with temporally patterned waveforms such as repetitive transcranial magnetic stimulation (rTMS) and transcranial alternating current stimulation (tACS) have been proposed to modulate these oscillations. Thus, these stimulation modalities represent promising new approaches for the treatment of psychiatric illnesses in which these oscillations are impaired. However, the mechanism by which periodic brain stimulation alters endogenous oscillation dynamics is debated and appears to depend on brain state. Here, we demonstrate with a static model and a neural oscillator model that recurrent excitation in the thalamo-cortical circuit, together with recruitment of cortico-cortical connections, can explain the enhancement of oscillations by brain stimulation as a function of brain state. We then performed concurrent invasive recording and stimulation of the human cortical surface to elucidate the response of cortical oscillations to periodic stimulation and support the findings from the computational models. We found that (1) stimulation enhanced the targeted oscillation power, (2) this enhancement outlasted stimulation, and (3) the effect of stimulation depended on behavioral state. Together, our results show successful target engagement of oscillations by periodic brain stimulation and highlight the role of nonlinear interaction between endogenous network oscillations and stimulation. These mechanistic insights will contribute to the design of adaptive, more targeted stimulation paradigms. PMID:27023427

  4. Neuropsychological improvement in patients with cervical spondylotic myelopathy after posterior decompression surgery

    International Nuclear Information System (INIS)

    Patients with cervical spondylotic myelopathy sometimes complain of cognitive dysfunction, which may be coincidence. However, cognitive dysfunction may be related to disorders of the cervical spine and/or spinal cord. This study investigated cognitive dysfunction in patients with cervical spinal disorders. A total of 79 patients with cervical spondylotic myelopathy (40 women and 39 men, mean age 61.2 years) underwent cervical laminoplasty between January 2006 and July 2007. Ten of these 79 patients (7 women and 3 men, mean age 65.2 years) complained of moderate to severe memory disturbances. These 10 patients underwent neuroimaging studies and a battery of neuropsychological tests consisting of the mini-mental state examination, Kohs Block Design Test, Miyake Memory Test, Benton Visual Retention Test (BVRT), and 'kana-hiroi' test before and 3 months after surgery. Brain magnetic resonance imaging showed no organic brain lesions in the 10 patients, but single photon emission computed tomography demonstrated reduced regional cerebral blood flow in the posterior cortical areas in eight patients before surgery. Neuropsychological test scores showed statistically significant improvement after surgery in the Kohs Block Design Test and the BVRT, which measure visuospatial perception and reflect the function of the parietal and/or occipital lobes (p<0.05). The practice effect may have contributed to the neuropsychological improvements, but this study suggests that cervical spinal disorders may affect cognitive functions and that surgical treatment can ameliorate such effects. (author)

  5. Visual assessment of posterior atrophy development of a MRI rating scale

    Energy Technology Data Exchange (ETDEWEB)

    Koedam, Esther L.G.E.; Scheltens, Philip; Pijnenburg, Yolande A.L. [VU University Medical Centre, Department of Neurology and Alzheimer Centre, PO Box 7057, MB, Amsterdam (Netherlands); Lehmann, Manja; Fox, Nick [UCL Institute of Neurology, Dementia Research Centre, London (United Kingdom); Flier, Wiesje M. van der [VU University Medical Centre, Department of Neurology and Alzheimer Centre, PO Box 7057, MB, Amsterdam (Netherlands); VU University Medical Centre, Department Epidemiology and Biostatistics, PO Box 7057, MB, Amsterdam (Netherlands); Barkhof, Frederik; Wattjes, Mike P. [VU University Medical Centre, Department of Radiology, PO Box 7057, MB, Amsterdam (Netherlands)

    2011-12-15

    To develop a visual rating scale for posterior atrophy (PA) assessment and to analyse whether this scale aids in the discrimination between Alzheimer's disease (AD) and other dementias. Magnetic resonance imaging of 118 memory clinic patients were analysed for PA (range 0-3), medial temporal lobe atrophy (MTA) (range 0-4) and global cortical atrophy (range 0-3) by different raters. Weighted-kappas were calculated for inter- and intra-rater agreement. Relationships between PA and MTA with the MMSE and age were estimated with linear-regression analysis. Intra-rater agreement ranged between 0.93 and 0.95 and inter-rater agreement between 0.65 and 0.84. Mean PA scores were higher in AD compared to controls (1.6 {+-} 0.9 and 0.6 {+-} 0.7, p < 0.01), and other dementias (0.8 {+-} 0.8, p < 0.01). PA was not associated with age compared to MTA (B = 1.1 (0.8) versus B = 3.1 (0.7), p < 0.01). PA and MTA were independently negatively associated with the MMSE (B = -1.6 (0.5), p < 0.01 versus B = -1.4 (0.5), p < 0.01). This robust and reproducible scale for PA assessment conveys independent information in a clinical setting and may be useful in the discrimination of AD from other dementias. (orig.)

  6. Insights from Neuropsychology: Pinpointing the role of the Posterior Parietal Cortex in Episodic and Working Memory

    Directory of Open Access Journals (Sweden)

    Marian E. Berryhill

    2012-06-01

    Full Text Available The role of posterior parietal cortex (PPC in various forms of memory is a current topic of interest in the broader field of cognitive neuroscience. This large cortical region has been linked with a wide range of mnemonic functions affecting each stage of memory processing: encoding, maintenance and retrieval. Yet, the precise role of the PPC in memory remains mysterious and controversial. Progress in understanding PPC function will require researchers to incorporate findings in a convergent manner from multiple experimental techniques rather than emphasizing a particular type of data. To facilitate this process, here, we review findings from the human neuropsychological research and examine the consequences to memory following PPC damage. Recent patient-based research findings have investigated two typically disconnected fields: working memory and episodic memory. The findings from patient participants with unilateral and bilateral PPC lesions performing diverse experimental paradigms are summarized. These findings are then related to findings from other techniques including neurostimulation (TMS and tDCS and the influential and more abundant functional neuroimaging literature. We then review the strengths and weaknesses of hypotheses proposed to account for PPC function in these forms of memory. Finally, we address what missing evidence is needed to clarify the role(s of the PPC in memory.

  7. Posterior reversible encephalopathy syndrome following acute pancreatitis during chemotherapy for acute monocytic leukemia.

    Science.gov (United States)

    Nishimoto, Mitsutaka; Koh, Hideo; Bingo, Masato; Yoshida, Masahiro; Nanno, Satoru; Hayashi, Yoshiki; Nakane, Takahiko; Nakamae, Hirohisa; Shimono, Taro; Hino, Masayuki

    2014-05-01

    We describe an 18-year-old man with acute leukemia who presented with posterior reversible encephalopathy syndrome (PRES) shortly after developing acute pancreatitis. On day 15 after the third consolidation course with high-dose cytarabine, treatment with broad-spectrum antibiotics was initiated for febrile neutropenia. On day 16, he developed septic shock, and subsequently, acute respiratory distress syndrome (ARDS). After adding vancomycin, micafungin and high-dose methylprednisolone (mPSL) to his treatment regimen, these manifestations subsided. On day 22, he received hemodialysis for drug-induced acute renal failure. On day 24, he developed acute pancreatitis possibly due to mPSL; the following day he had generalized seizures, and was intubated. Cerebrospinal fluid findings were normal. Brain MRI revealed hyperintense signals on FLAIR images and increased apparent diffusion coefficient values in the sub-cortical and deep white matter areas of the bilateral temporal and occipital lobes, indicative of vasogenic edema. Thus, we diagnosed PRES. Blood pressure, seizures and volume status were controlled, with MRI findings showing improvement by day 42. He was extubated on day 32 and discharged on day 49 without complications. Although little is known about PRES following acute pancreatitis, clinicians should be aware that this condition may develop. PMID:24881921

  8. Visual assessment of posterior atrophy development of a MRI rating scale

    International Nuclear Information System (INIS)

    To develop a visual rating scale for posterior atrophy (PA) assessment and to analyse whether this scale aids in the discrimination between Alzheimer's disease (AD) and other dementias. Magnetic resonance imaging of 118 memory clinic patients were analysed for PA (range 0-3), medial temporal lobe atrophy (MTA) (range 0-4) and global cortical atrophy (range 0-3) by different raters. Weighted-kappas were calculated for inter- and intra-rater agreement. Relationships between PA and MTA with the MMSE and age were estimated with linear-regression analysis. Intra-rater agreement ranged between 0.93 and 0.95 and inter-rater agreement between 0.65 and 0.84. Mean PA scores were higher in AD compared to controls (1.6 ± 0.9 and 0.6 ± 0.7, p < 0.01), and other dementias (0.8 ± 0.8, p < 0.01). PA was not associated with age compared to MTA (B = 1.1 (0.8) versus B = 3.1 (0.7), p < 0.01). PA and MTA were independently negatively associated with the MMSE (B = -1.6 (0.5), p < 0.01 versus B = -1.4 (0.5), p < 0.01). This robust and reproducible scale for PA assessment conveys independent information in a clinical setting and may be useful in the discrimination of AD from other dementias. (orig.)

  9. Functionally aberrant electrophysiological cortical connectivities in first episode medication-naive schizophrenics from three psychiatry centers

    Directory of Open Access Journals (Sweden)

    Dietrich Lehmann‡

    2014-08-01

    Full Text Available Functional dissociation between brain processes is widely hypothesized to account for aberrations of thought and emotions in schizophrenic patients. The typically small groups of analyzed schizophrenic patients yielded different neurophysiological findings, probably because small patient groups are likely to comprise different schizophrenia subtypes. We analyzed multichannel eyes-closed resting EEG from three small groups of acutely ill, first episode productive schizophrenic patients before start of medication (from three centers: Bern N=9; Osaka N=9; Berlin N=12 and their controls. Low resolution brain electromagnetic tomography (LORETA was used to compute intracortical source model-based lagged functional connectivity not biased by volume conduction effects between 19 cortical regions of interest (ROIs. The connectivities were compared between controls and patients of each group. Conjunction analysis determined six aberrant cortical functional connectivities that were the same in the three patient groups. Four of these six concerned the facilitating EEG alpha 1 frequency activity; they were decreased in the patients. Another two of these six connectivities concerned the inhibiting EEG delta frequency activity; they were increased in the patients. The principal orientation of the six aberrant cortical functional connectivities was sagittal; five of them involved both hemispheres. In sum, activity in the posterior brain areas of preprocessing functions and the anterior brain areas of evaluation and behavior control functions were compromised by either decreased coupled activation or increased coupled inhibition, common across schizophrenia subtypes in the three patient groups. These results of the analyzed three independent groups of schizophrenics support the concept of functional dissociation.

  10. Cortical localization of phase and amplitude dynamics predicting access to somatosensory awareness.

    Science.gov (United States)

    Hirvonen, Jonni; Palva, Satu

    2016-01-01

    Neural dynamics leading to conscious sensory perception have remained enigmatic in despite of large interest. Human functional magnetic resonance imaging (fMRI) studies have revealed that a co-activation of sensory and frontoparietal areas is crucial for conscious sensory perception in the several second time-scale of BOLD signal fluctuations. Electrophysiological recordings with magneto- and electroencephalography (MEG and EEG) and intracranial EEG (iEEG) have shown that event related responses (ERs), phase-locking of neuronal activity, and oscillation amplitude modulations in sub-second timescales are greater for consciously perceived than for unperceived stimuli. The cortical sources of ER and oscillation dynamics predicting the conscious perception have, however, remained unclear because these prior studies have utilized MEG/EEG sensor-level analyses or iEEG with limited neuroanatomical coverage. We used a somatosensory detection task, magnetoencephalography (MEG), and cortically constrained source reconstruction to identify the cortical areas where ERs, local poststimulus amplitudes and phase-locking of neuronal activity are predictive of the conscious access of somatosensory information. We show here that strengthened ERs, phase-locking to stimulus onset (SL), and induced oscillations amplitude modulations all predicted conscious somatosensory perception, but the most robust and widespread of these was SL that was sustained in low-alpha (6-10 Hz) band. The strength of SL and to a lesser extent that of ER predicted conscious perception in the somatosensory, lateral and medial frontal, posterior parietal, and in the cingulate cortex. These data suggest that a rapid phase-reorganization and concurrent oscillation amplitude modulations in these areas play an instrumental role in the emergence of a conscious percept. PMID:26485310

  11. Comparison of relative split renal function with DMSA using posterior static imaging only with combined anterior-posterior acquisition

    International Nuclear Information System (INIS)

    Aim: Protocols for evaluation of renal function with DMSA vary from simple posterior static imaging to more time-consuming methods including anterior and posterior views with depth correction. The aim of this study was to investigate if there is a clinically significant difference between values of relative split renal function using a single posterior image (SP) or combined data from anterior and posterior acquisitions (AP). Material and Methods: We studied 21 consecutive patients, 14 children (ages 2.34±3 years) and 7 adults (ages 54.6±21 years) with a variety of pathologic conditions referred for renal evaluation. All patients had normotopic, bilaterally functioning kidneys. All were injected intravenously with a dose of 1.48 MBq/kg (0.04 mCi/kg) of 99mTc-DMSA and studies acquired 4-6 hours later. Static images were obtained for 5 minutes each, in the posterior and then in the anterior projection with a large field-of-view rectangular gamma camera equipped with a high resolution collimator, using a 64x64 matrix with zoom factor as required. Regions of interest were drawn using a semi-automatic thresholding method for the kidneys with semi-crescent automatic background (BKG) areas. Relative differential function was then calculated using the software provided with the system. One method uses posterior image only with no depth correction and the other uses both anterior and posterior views, requiring the patient's body thickness in cm for geometrical mean calculation plus depth correction. For the first method, the following simple formula is used: Left (or right) % uptake = Left (or right) BKG corrected cts/Left + right BKG corrected cts. For the second method, each kidney counts are first calculated as follows: Kidney counts √(anterior x posterior BKG corrected cts).eμ.T/2. K, where μ is the linear attenuation coefficient (1.22 cm-1), T is the body thickness in cm and K=1. Results: The following values of relative split functions for SP/AP methods were: 48

  12. Posterior Ischemic Optic Neuropathy Following Percutaneous Nephrolithotomy

    Directory of Open Access Journals (Sweden)

    Mohammad Pakravan

    2008-12-01

    Full Text Available

    PURPOSE: To report a case of posterior ischemic optic neuropathy (PION following percutaneous nephrolithotomy (PCNL. CASE REPORT: A 57-year-old man with history of diabetes mellitus, hyperlipidemia and mild anemia underwent PCNL for treatment of nephrolithiasis. He noticed painless visual loss in both eyes immediately after the procedure. Visual acuity was light perception, however ophthalmologic examinations were unremarkable and the optic discs were pink with no swelling. Visual fields were severely affected, but neuro-imaging was normal. Within three months, visual acuity and visual fields improved dramatically but the optic discs became slightly pale. CONCLUSION: This is the first report of PION following PCNL. PION is a rare cause of severe visual loss following surgery. Severe blood loss, hypotension, anemia and body position during surgery are the most important risk factors. Ophthalmologists, urologists and anesthesiologists should be aware of this condition and this rare possibility should be considered prior to surgery.

  1. Posteriorly migrated thoracic disc herniation: a case report

    Directory of Open Access Journals (Sweden)

    Miyakoshi Naohisa

    2013-02-01

    Full Text Available Abstract Introduction Posterior epidural migration of thoracic disc herniation is extremely rare but may occur in the same manner as in the lumbar spine. Case presentation A 53-year-old Japanese man experienced sudden onset of incomplete paraplegia after lifting a heavy object. Magnetic resonance imaging revealed a posterior epidural mass compressing the spinal cord at the T9-T10 level. The patient underwent emergency surgery consisting of laminectomy at T9-T10 with right medial facetectomy, removal of the mass lesion, and posterior instrumented fusion. Histological examination of the mass lesion yielded findings consistent with sequestered disc material. His symptoms resolved, and he was able to resume walking without a cane 4 weeks after surgery. Conclusions Pre-operative diagnosis of posterior epidural migration of herniated thoracic disc based on magnetic resonance imaging alone may be overlooked, given the rarity of this pathology. However, this entity should be considered among the differential diagnoses for an enhancing posterior thoracic extradural mass.

  2. Flexor Digitorum Accessorius Longus: Importance of Posterior Ankle Endoscopy

    Directory of Open Access Journals (Sweden)

    Jorge Pablo Batista

    2015-01-01

    Full Text Available Endoscopy for the posterior region of the ankle through two portals is becoming more widespread for the treatment of a large number of conditions which used to be treated with open surgery years ago. The tendon of the flexor hallucis longus (FHL travels along an osteofibrous tunnel between the posterolateral and posteromedial tubercles of the talus. Chronic inflammation of this tendon may lead to painful stenosing tenosynovitis. The aim of this report is to describe two cases depicting an accessory tendon which is an anatomical variation of the flexor hallucis longus in patients with posterior friction syndrome due to posterior ankle impingement and associated with a posteromedial osteochondral lesion of the talus. The anatomical variation (FDAL described was a finding during an endoscopy of the posterior region of the ankle, and we have spared it by sectioning the superior flexor retinaculum only. The accessory flexor digitorum longus is an anatomical variation and should be taken into account when performing an arthroscopy of the posterior region of the ankle. We recommend this treatment on this type of injury although we admit this does not make a definite conclusion.

  3. Posterior urethral valves: Morphological normalization of posterior urethra after fulguration is a significant factor in prognosis

    Directory of Open Access Journals (Sweden)

    Menon Prema

    2010-01-01

    Full Text Available Aim: To assess the changes in urethral morphology 3 months post fulguration of posterior urethral valves (PUVs on micturating cystourethrogram (MCUG and correlate these changes with the overall clinical status of the patient. Materials and Methods: A total of 217 children, managed for PUVs during a period of 6 years in a single surgical unit were prospectively studied. The ratio of the diameters of the prostatic and bulbar urethras (PU/BU was calculated on the pre- and post-fulguration MCUG films. They were categorized into three groups based on the degree of normalization of posterior urethra (post-fulguration PU/BU ratio. Results: Group A: Of the 133 patients, 131 had normal urinary stream and 4 (3% had nocturnal enuresis. Vesicoureteral reflux (VUR, initially seen in 83 units (31% units, regressed completely at a mean duration of 6 months in 41 units (49%. Of the 152 non-VUR, hydroureteronephrosis (HUN units, 11 were poorly functioning kidneys. Persistent slow but unobstructed drainage was seen in 23 units (16% over a period of 1.5-5 years (mean 2.5 years. Group B: All the 11 patients had a normal stream. Four (36.4% had daytime frequency for a mean duration of 1 year and one (9% had nocturnal enuresis for 1 year. Grade IV-V VUR was seen in five patients (three bilateral, which regressed completely by 3 months in five units (62.5%. In the non-VUR, HUN patients, slow (but unobstructed drainage was persistent in two units (14% at 3 years. Group C: Of the 16 patients, only 5 (31.3% were asymptomatic. Six patients (nine units had persistent VUR for 6 months to 3 years. Of the 20 units with HUN, 17 (85% were persistent at 1-4 years (mean 2 years. Eight patients (50% required a second fulguration while 3 (18.7% required urethral dilatation for stricture following which all parameters improved. Conclusions: Adequacy of fulguration should be assessed by a properly performed MCUG. A postop PU/BU ratio >3 SD (1.92 should alert to an incomplete

  4. Bispectral index correlates with regional cerebral blood flow during sleep in distinct cortical and subcortical structures in humans.

    Science.gov (United States)

    Noirhomme, Q; Boly, M; Bonhomme, V; Boveroux, P; Phillips, C; Peigneux, P; Soddu, A; Luxen, A; Moonen, G; Maquet, P; Laureys, S

    2009-03-01

    The relationship between the Bispectral Index (BIS), an EEG-based monitor of anesthesia, and brain activity is still unclear. This study aimed at investigating the relationship between changes in BIS values during natural sleep and regional cerebral blood flow (rCBF) variations, as measured by Positron Emission Tomography (PET). Data were obtained from six young, healthy, right-handed, male volunteers (20-30 years old) using the H2(15)O infusion method. PET scans were performed both during waking and various stages of sleep. BIS values were monitored continuously and recorded during each PET scan. Positive correlations were detected between BIS and rCBF values in dorsolateral prefontal, parietal, anterior and posterior cingulate, precuneal, mesiofrontal, mesiotemporal and insular cortices. These areas belong to a frontoparietal network known to be related to awareness of self conscious sensory perception, attention and memory. BIS values also positively correlated with activity in brainstem and thalami, both structures known to be involved in arousal and wakefulness. These results show that BIS changes associated with physiological sleep depth co-vary with the activity of specific cortical and subcortical areas. The latter are known to modulate arousal, which in turn allows sustained thalamo-cortical enhancement of activity in a specific frontoparietal network known to be related to the content of consciousness. Thus, although mainly derived from frontal EEG, BIS could represent a wider index of cerebral activity. PMID:19678596

  5. Censoring Distances Based on Labeled Cortical Distance Maps in Cortical Morphometry

    Directory of Open Access Journals (Sweden)

    ElvanCeyhan

    2013-10-01

    Full Text Available It has been demonstrated that shape differences are manifested in cortical structures due to neuropsychiatric disorders. Such morphometric differences can be measured by labeled cortical distance mapping (LCDM which characterizes the morphometry of the laminar cortical mantle of cortical structures. LCDM data consist of signed/labeled distances of gray matter (GM voxels with respect to GM/white matter (WM surface. Volumes and other summary measures for each subject and the pooled distances can help determine the morphometric differences between diagnostic groups, however they do not reveal all the morphometric information con-tained in LCDM distances. To extract more information from LCDM data, censoring of the pooled distances is introduced for each diagnostic group where the range of LCDM distances is partitioned at a fixed increment size; and at each censoring step, the distances not exceeding the censoring distance are kept. Censored LCDM distances inherit the advantages of the pooled distances but also provide information about the location of morphometric differences which cannot be obtained from the pooled distances. However, at each step, the censored distances aggregate, which might confound the results. The influence of data aggregation is investigated with an extensive Monte Carlo simulation analysis and it is demonstrated that this influence is negligible. As an illustrative example, GM of ventral medial prefrontal cortices (VMPFCs of subjects with major depressive disorder (MDD, subjects at high risk (HR of MDD, and healthy control (Ctrl subjects are used. A significant reduction in laminar thickness of the VMPFC in MDD and HR subjects is observed compared to Ctrl subjects. Moreover, the GM LCDM distances (i.e., locations with respect to the GM/WM surface for which these differences start to occur are determined. The methodology is also applicable to LCDM-based morphometric measures of other cortical structures affected by disease.

  6. Posterior vaginal wall cyst of Mullerian origin: a case report

    Directory of Open Access Journals (Sweden)

    Sunita Samal

    2015-02-01

    Full Text Available Cystic lesions of vagina are relatively uncommon and an incidental finding during routine gynaecological examination. Mullerian cysts are congenital cysts of vagina, usually reported during childbearing age group. These cysts mostly arise at the level of cervix and extend anteriorly in relation to bladder, but very rarely they may also extend posteriorly. This is a rare case of posterior vaginal wall cyst of Mullerian origin. A 36-year-old multi para (P2L2 both SVD, presented with a mass descending through vagina since 2-3 months. Pelvic examination revealed a 5x5 cm cystic mass arising from the posterior vaginal wall. Complete excision of the cyst was done. The cyst was filled with chocolate coloured material and histopathology confirmed a Mullerian cyst. [Int J Reprod Contracept Obstet Gynecol 2015; 4(1.000: 245-246

  7. Ganglion cyst of the posterior cruciate ligament in a child.

    Science.gov (United States)

    Hameed, Shamsi Abdul; Sujir, Premjit; Naik, Monappa A; Rao, Sharath K

    2012-04-01

    Ganglion cysts are more commonly associated with the anterior cruciate ligament than the posterior cruciate ligament (PCL). A literature review showed that all reported cases of ganglion cysts to date involved adults. We report a rare case of ganglion cyst in the PCL of a four-year-old boy, and discuss its aetiology, clinical presentation, imaging features and management. Ganglion cysts of the PCL may be confused with meniscal cysts arising from tears of the posterior horn of the medial meniscus on magnetic resonance (MR) imaging. Hence, the posterior horn of the medial meniscus has to be carefully evaluated to rule out a tear. MR imaging is the method of choice to confirm diagnosis, and arthroscopic resection is a safe treatment modality even in children. PMID:22511069

  8. Relationship between posterior crossbite and postural alterations in children

    Directory of Open Access Journals (Sweden)

    Juliana Jaqueline de Matos Lopes

    2009-12-01

    Full Text Available Objective: To evaluate the posture of individuals with functional posterior crossbite, malocclusion is one of the most in need of orthodontic treatment. Methods: This work presents an analysis of postural among children 6 to 12 years who present functional posterior cross bite of both genders who are in mixed dentition or no intervention prior orthodontic and orthopedic. Was obtained images in the plans: front and back where it was analyzed the asymmetry or symmetry of the individual in the image and in the lateral, anterior, a posterior or normality. Results: 100% had some kind of postural change, and the asymmetry between the scapulae (shoulder found the greatest change, as one of extreme importance in this age group represents a growing skeletal muscle. Conclusion: analyzes all of the children showed postural abnormalities and malocclusion are also of great importance not only to be treating the problem orally, but the postural problem with the help of a multidisciplinary team.

  9. Lumbar posterior marginal intra-osseous cartilaginous node

    Energy Technology Data Exchange (ETDEWEB)

    Laredo, J.D.; Bard, M.; Chretien, J.; Kahn, M.F.

    1986-03-01

    This report concerns 12 patients, eight young adults and four adolescents, presenting with lumbar or sciatic pain. This was associated with an unusual defect of the inferior and posterior edges of the vertebral bodies of L4 or L5, together with a small bony ridge protruding into the spinal canal. We found 11 similar cases in the literature, all involving adolescents except for one young adult. It has been considered to be the result of a fracture of the posterior ring apophysis in association with a herniated disc. In our cases, in the absence of any known previous trauma, the radiological features and surgical results and the similarity and frequent association with typical lesions of Scheuermann disease, all suggest a posterior marginal cartilaginous node. The inferior lumbar location and frequent association with herniated disc and sciatic nerve root compression in young patients are discussed.

  10. Factors affecting visualization of posterior rib fractures in abused infants

    International Nuclear Information System (INIS)

    Rib fractures in abused infants commonly occur in the posterior rib arcs. Fractures occurring near the costovertebral articulations are usually identified radiographically only once callus has formed. To assess the factors influencing the visibility of fractures near the costovertical articulations, the authors studied 103 posterior rib fractures occurring in 16 abused infants. Radiologic findings were correlated with CT findings and pathologic material from nine ribs in four patients. The limited visibility of fractures relates to (1) the frequent superimposition of the transverse process over the rib fracture site, (2) a fracture line that crosses at an obliquity to the x-ray beam, and (3) nondisplacement of rib fragments due to preservation of the posterior periosteum. Fresh rib fractures invisible on a frontal projection may be clearly defined on axial CT scans, or on postmortem radiographs. A knowledge of the factors influencing the visibility of these important injuries is useful in planning an appropriate diagnostic evaluation of suspected infant abuse

  11. Mature Teratoma of the Posterior Mediastinum: A Case Report

    Directory of Open Access Journals (Sweden)

    R Mahmoudlo

    2008-12-01

    Full Text Available Mature teratomas are the most common type of mediastinal germ cell tumors. They typically occur in young adults (15 to 35 years and 95% of these teratomas occur in the anterior mediastinum. Herein, we report a case of a huge mediastinal teratoma in a 16-year-old boy who presented with a history of chest pain, cough, exertional dyspnea, and fever. Chest X-ray and spiral computed tomography (CT revealed a bulky mass of 20×15 cm in the right side of the posterior mediastinum. The operative finding was a large cystic mass in the posterior mediastinum adherent to the neighbor organs. The cyst was filled with sebum, hair and calcified materials. The resected tumor was in the posterior mediastinum, although most of these tumors occur in the anterior mediastinum. To the best of our knowledge, this is the first documented report in Iran.

  12. The posterior bone block procedure in posterior shoulder instability: a long-term follow-up study.

    Science.gov (United States)

    Meuffels, D E; Schuit, H; van Biezen, F C; Reijman, M; Verhaar, J A N

    2010-05-01

    We present the long-term outcome, at a median of 18 years (12.8 to 23.5) of open posterior bone block stabilisation for recurrent posterior instability of the shoulder in a heterogenous group of 11 patients previously reported on in 2001 at a median follow-up of six years. We found that five (45%) would not have chosen the operation again, and that four (36%) had further posterior dislocation. Clinical outcome was significantly worse after 18 years than after six years of follow-up (median Rowe score of 60 versus 90 (p = 0.027)). The median Western Ontario Shoulder Index was 60% (37% to 100%) at 18 years' follow-up, which is a moderate score. At the time of surgery four (36%) had glenohumeral radiological osteoarthritis, which was present in all after 18 years. This study showed poor long-term results of the posterior bone block procedure for posterior instability and a high rate of glenohumeral osteoarthritis although three patients with post-traumatic instability were pleased with the result of their operations. PMID:20436001

  13. Absent posterior semicircular canal: HRCT feature of Waardenburg syndrome

    Directory of Open Access Journals (Sweden)

    Sandeep M Mahajan

    2012-01-01

    Full Text Available Absence of posterior semicircular canal is a rare condition, having been reported with only a few syndromes such as Waardenburg syndrome (WS, Alagellie, CHARGE, and Goldenhaar syndromes. We report a 12- year old male with bilateral absent posterior semicircular canals. These phenotypic characteristics of the patient favored the diagnosis of WS. WS is a rare autosomal dominant condition characterized by sensorineural hearing loss, in conjunction with pigmentary abnormalities and defects of the neural crest-derived tissues. The case is presented for its rarity and for its high resolution computed tomography (HRCT temporal bone findings so as to reach a precise diagnosis.

  14. Non-traumatic posterior atlanto-occipital joint dislocation

    OpenAIRE

    Takechi, Yasuhiko; Iizuka, Haku; Sorimachi, Yasunori; Ara, Tsuyoshi; Nishinome, Masahiro; Takagishi, Kenji

    2010-01-01

    This report presents a case of non-traumatic posterior atlanto-occipital dislocation. A 36-year-old female was referred with a history of numbness of the extremities, vertigo and neck pain for 1 year. The patient had no history of trauma. The axial rotation of range of motion of the cervical spine was severely restricted. A lateral cervical radiograph in the neutral position demonstrated a posterior atlanto-occipital dislocation. A coronal view on a computed tomography (CT) reconstruction ima...

  15. Superior labrum anterior to posterior tears in throwing athletes.

    Science.gov (United States)

    Lintner, David M

    2013-01-01

    Superior labrum anterior to posterior (SLAP) tears and partial undersurface tears of the rotator cuff are common in experienced throwers, may be adaptive, and are only occasionally symptomatic. Pain in the shoulder of a throwing athlete with an MRI-documented SLAP tear or partial undersurface tear of the rotator cuff can be managed nonsurgically, with attention to posterior capsular contracture, scapular dyskinesia, and rotator cuff strength. The results of the surgical repair of SLAP lesions in the throwing athlete, with or without rotator cuff repair, are inferior to those of nonsurgical treatment. The cause of pain in the throwing athlete must be accurately diagnosed without reliance on MRI findings. PMID:23395053

  16. Alterations in right posterior hippocampus in early blind individuals

    DEFF Research Database (Denmark)

    Chebat, Daniel-Robert; Chen, Jan-Kai; Schneider, Fabien;

    2007-01-01

    between groups and there were no within-group differences for left versus right hippocampus. Sex, age and total brain grey matter volume had no effect on hippocampal volumes. Although extensive navigational training results in structural enhancement of the hippocampus for the sighted, the reduction of the......This study compares hippocampal volumes of early blind and sex/age-matched sighted controls through volumetric and localization analyses. Early blind individuals showed a significantly smaller right posterior hippocampus compared with controls. No differences in total hippocampal volumes were found...... posterior hippocampus in early blind individuals suggests the implication of this region in visual spatial memory. Udgivelsesdato: 2007-Mar-5...

  17. Posterior mediastinal hemangioma mimicking neurogenic tumor: A case report

    Energy Technology Data Exchange (ETDEWEB)

    Song, Han Byeoul; Park, Jong Chun [Dept. of Radiology, Daegu Catholic University Medical Center, Catholic University of Daegu College of Medicine, Daegu (Korea, Republic of)

    2015-07-15

    Mediastinal hemangioma is a benign vascular tumor and is located most frequently in the anterior mediastinum. Computed tomography showed a well-marginated central enhancing mass with extension into the adjacent foramen. The mass was relatively hyperintense to the skeletal muscle on T2-weighted image and on fat-saturated T1-weighted image with gadolinium enhancement. The tumor was confirmed to be a cavernous hemangioma by pathologic examination after surgery. The authors recently experienced a cavernous hemangioma in the posterior mediastinum. Thus, we report a case of a posterior mediastinal mass which was difficult to differentiate from a neurogenic tumor.

  18. Management of Posterior Reversible Syndrome in Preeclamptic Women

    Directory of Open Access Journals (Sweden)

    S. Poma

    2014-01-01

    Full Text Available Posterior reversible encephalopathy syndrome (PRES is a neurological syndrome associated with a number of conditions including preeclampsia. It is characterized by seizures, alteration of consciousness, visual disturbances, and symmetric white matter abnormalities, typically in the posterior parietooccipital regions of the cerebral hemispheres, at computed tomography (CT and magnetic resonance (MRI. We report three new cases of PRES in preeclamptic patients and describe the management of these patients. We present a brief review of other cases in the literature, with particular attention to the anesthetic management.

  19. Missed posterior shoulder dislocation with malunited proximal humerus fracture

    Institute of Scientific and Technical Information of China (English)

    Sunil Kumar; Rajesh Kumar Chopra; Abhishek Kashyap; Sumit Arora

    2013-01-01

    Posterior dislocation of the shoulder may be missed or neglected at initial presentation especially in developing countries.We present a case of 40-year-old Indian man who had 3-month missed posterior dislocation of the right shoulder along with malunited fracture of the anatomical neck of the humerus.Open reduction and stabilization with modified McLaughlin procedure was performed.Rotational osteotomy of proximal humerus had to be performed as supplementary procedure to keep the humeral head stable in glenoid cavity during functional range of movements.The patient had excellent result of the shoulder at 3 years follow-up.

  20. Spindle cell lipoma of the posterior axilla: a case report

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jee Young; Suh, Kyung Jin; Kim, Sang Yoon [Dongguk University Hospital, Cheonan (Korea, Republic of)

    2008-07-15

    Spindle cell lipoma is characterized by different cell components, mature adipocytes, spindle cells and collagen bundles, and it presents as a well-defined benign fatty mass on the posterior neck or upper back of middle aged men. As a result of the various ratios of non-adipose tissue, it is difficult to differentiate spindle cell lipoma from liposarcoma. To the best of our knowledge, the imaging features of spindle cell lipoma have not been reported in Korea. We report here on the imaging findings of a histologically confirmed spindle cell lipoma in the subcutaneous layer of the posterior axilla.