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Sample records for atrofia cortical posterior

  1. Dos casos de atrofia cortical posterior, la demencia que inicia con síntomas visuales.

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    Custodio, Nilton; Unidad de Investigación. Instituto Peruano de Neurociencias. Lima, Perú. Servicio de Neurología. Clínica Internacional. Lima, Perú. Unidad de Diagnóstico de Deterioro Cognitivo y Prevención de Demencia. Clínica Internacional. Lima.; Lira, David; Unidad de Investigación. Instituto Peruano de Neurociencias. Lima, Perú. Servicio de Neurología. Clínica Internacional. Lima, Perú. Unidad de Diagnóstico de Deterioro Cognitivo y Prevención de Demencia. Clínica Internacional. Lima.; Herrera-Pérez, Eder; Unidad de Investigación. Instituto Peruano de Neurociencias. Lima. Unidad de Diagnóstico de Deterioro Cognitivo y Prevención de Demencia. Clínica Internacional. Lima. Servicio de Medicina de Rehabilitación. Clínica Internacional. Lima.; Montesinos, Rosa; Unidad de Investigación. Instituto Peruano de Neurociencias. Lima. Unidad de Diagnóstico de Deterioro Cognitivo y Prevención de Demencia. Clínica Internacional. Lima. Servicio de Medicina de Rehabilitación. Clínica Internacional. Lima.; Guevara-Silva, Erik; Departamento de Medicina. Hospital San Juan de Lurigancho. Lima.; Núñez del Prado, Liza; Unidad de Investigación. Instituto Peruano de Neurociencias. Lima.; Castro-Suárez, Sheila; Unidad de Investigación. Instituto Peruano de Neurociencias. Lima. Servicio de Neurología de la Conducta. Instituto Nacional de Ciencias Neurológicas. Lima.; Mar, Marcela; Unidad de Investigación. Instituto Peruano de Neurociencias. Lima. Servicio de Geriatría. Hospital de la Fuerza Aérea del Perú. Lima.; Cuenca, José; Unidad de Investigación. Instituto Peruano de Neurociencias. Lima. Servicio de Neurología de la Conducta. Instituto Nacional de Ciencias Neurológicas. Lima,; Cortijo, Patricia; Unidad de Investigación. Instituto Peruano de Neurociencias. Lima, Perú. Unidad de Diagnóstico de Deterioro Cognitivo y Prevención de Demencia. Clínica Internacional. Lima.

    2014-01-01

    Presentamos dos casos de demencia de inicio antes de los 65 años de edad con apraxia y manifestaciones visuo-espaciales, en los cuales no hay trastornos de memoria y de la conducta, y con diferentes grados de evolución a demencia. Las imágenes estructurales del cerebro demuestran atrofia parieto-occipital. Ambos casos reúnen los criterios de atrofia cortical posterior (ACP).

  2. Reversible cortical blindness: posterior reversible encephalopathy syndrome.

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    Bandyopadhyay, Sabyasachi; Mondal, Kanchan Kumar; Das, Somnath; Gupta, Anindya; Biswas, Jaya; Bhattacharyya, Subir Kumar; Biswas, Gautam

    2010-11-01

    Cortical blindness is defined as visual failure with preserved pupillary reflexes in structurally intact eyes due to bilateral lesions affecting occipital cortex. Bilateral oedema and infarction of the posterior and middle cerebral arterial territory, trauma, glioma and meningioma of the occipital cortex are the main causes of cortical blindness. Posterior reversible encephalopathy syndrome (PRES) refers to the reversible subtype of cortical blindness and is usually associated with hypertension, diabetes, immunosuppression, puerperium with or without eclampsia. Here, 3 cases of PRES with complete or partial visual recovery following treatment in 6-month follow-up are reported.

  3. Posterior cortical atrophy: a brief review.

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    Kirshner, Howard S; Lavin, Patrick J M

    2006-11-01

    Posterior cortical atrophy is a striking clinical syndrome in which a dementing illness begins with visual symptoms. Initially, the problem may seem to be loss of elementary vision, but over time the patient develops features of visual agnosia, topographical difficulty, optic ataxia, simultanagnosia, ocular apraxia (Balint's syndrome), alexia, acalculia, right-left confusion, and agraphia (Gerstmann's syndrome), and later a more generalized dementia. Occasional patients have visual hallucinations and signs of Parkinson's disease or Lewy body dementia. A number of different neuropathologic disorders are associated with posterior cortical atrophy.

  4. 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

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    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.

  5. Bilateral cortical atrophy after severe brain trauma and extradural homatoma Atrofia cortical bilateral após traumatismo cranioencefálico grave e hematoma extradural

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    Paulo Roberto Louzada

    2007-12-01

    Full Text Available We report the case of a severe head injured 43-year old male patient with a large extradural hematoma, Glasgow Coma Scale 3 and dilated fixed pupils. Patient was promptly submitted to surgical evacuation of the lesion, but remained in persistent vegetative state in the post-operative time. Head computed tomography scans performed before surgery, and at early and late post-operative periods comparatively revealed extreme bilateral cortical atrophy. Late consequences of severe head trauma drastically affect the prognosis of patients, being its prevention, and neuroprotection against secondary injury still a therapeutical challenge for neurosurgeons.Relatamos o caso de um paciente de 43 anos, com traumatismo cranioencefálico grave, com grande hematoma extradural, Escala de Coma de Glasgow 3 e pupilas fixas e dilatadas. O paciente foi prontamente submetido à evacuação cirúrgica da lesão mas permaneceu em estado vegetativo persistente no período pós-operatório. As TC de crânio realizadas antes da cirurgia e nos períodos pós-operatórios precoce e tardio revelaram comparativamente extrema atrofia cerebral bilateral. As conseqüências tardias do traumatismo craniano grave afetam drasticamente o prognóstico dos pacientes, sendo sua prevenção, e a neuroproteção contra a injúria secundária ainda um desafio terapêutico para os neurocirurgiões.

  6. Neural correlates of cognitive impairment in posterior cortical atrophy.

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    Kas, Aurélie; de Souza, Leonardo Cruz; Samri, Dalila; Bartolomeo, Paolo; Lacomblez, Lucette; Kalafat, Michel; Migliaccio, Raffaella; Thiebaut de Schotten, Michel; Cohen, Laurent; Dubois, Bruno; Habert, Marie-Odile; Sarazin, Marie

    2011-05-01

    With the prospect of disease-modifying drugs that will target the physiopathological process of Alzheimer's disease, it is now crucial to increase the understanding of the atypical focal presentations of Alzheimer's disease, such as posterior cortical atrophy. This study aimed to (i) characterize the brain perfusion profile in posterior cortical atrophy using regions of interest and a voxel-based approach; (ii) study the influence of the disease duration on the clinical and imaging profiles; and (iii) explore the correlations between brain perfusion and cognitive deficits. Thirty-nine patients with posterior cortical atrophy underwent a specific battery of neuropsychological tests, mainly targeting visuospatial functions, and a brain perfusion scintigraphy with 99mTc-ethyl cysteinate dimer. The imaging analysis included a comparison with a group of 24 patients with Alzheimer's disease, matched for age, disease duration and Mini-Mental State Examination, and 24 healthy controls. The single-photon emission computed tomography profile in patients with posterior cortical atrophy was characterized by extensive and severe hypoperfusion in the occipital, parietal, posterior temporal cortices and in a smaller cortical area corresponding to the frontal eye fields (Brodmann areas 6/8). Compared with patients with Alzheimer's disease, the group with posterior cortical atrophy showed more severe occipitoparietal hypoperfusion and higher perfusion in the frontal, anterior cingulate and mesiotemporal regions. When considering the disease duration, the functional changes began and remained centred on the posterior lobes, even in the late stage. Correlation analyses of brain perfusion and neuropsychological scores in posterior cortical atrophy highlighted the prominent role of left inferior parietal damage in acalculia, Gerstmann's syndrome, left-right indistinction and limb apraxia, whereas damage to the bilateral dorsal occipitoparietal regions appeared to be involved in B

  7. 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

  8. Visual neglect in posterior cortical atrophy

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    Andrade Katia

    2010-08-01

    Full Text Available Abstract Background In posterior cortical atrophy (PCA, there is a progressive impairment of high-level visual functions and parietal damage, which might predict the occurrence of visual neglect. However, neglect may pass undetected if not assessed with specific tests, and might therefore be underestimated in PCA. In this prospective study, we aimed at establishing the side, the frequency and the severity of visual neglect, visual extinction, and primary visual field defects in an unselected sample of PCA patients. Methods Twenty-four right-handed PCA patients underwent a standardized battery of neglect tests. Visual fields were examined clinically by the confrontation method. Results Sixteen of the 24 patients (66% had signs of visual neglect on at least one test, and fourteen (58% also had visual extinction or hemianopia. Five patients (21% had neither neglect nor visual field defects. As expected, left-sided neglect was more severe than right-sided neglect. However, right-sided neglect resulted more frequently in this population (29% than in previous studies on focal brain lesions. Conclusion When assessed with specific visuospatial tests, visual neglect is frequent in patients with PCA. Diagnosis of neglect is important because of its negative impact on daily activities. Clinicians should consider the routine use of neglect tests to screen patients with high-level visual deficits. The relatively high frequency of right-sided neglect in neurodegenerative patients supports the hypothesis that bilateral brain damage is necessary for right-sided neglect signs to occur, perhaps because of the presence in the right hemisphere of crucial structures whose damage contributes to neglect.

  9. Posterior cortical atrophy: an atypical variant of Alzheimer disease.

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    Suárez-González, Aida; Henley, Susie M; Walton, Jill; Crutch, Sebastian J

    2015-06-01

    Posterior cortical atrophy (PCA) is a neurodegenerative syndrome characterized by striking progressive visual impairment and a pattern of atrophy mainly involving posterior cortices. PCA is the most frequent atypical presentation of Alzheimer disease. The purpose of this article is to provide a summary of PCA's neuropsychiatric manifestations. Emotional and psychotic symptoms are discussed in the context of signal characteristic features of the PCA syndrome (the early onset, focal loss of visual perception, focal posterior brain atrophy) and the underlying cause of the disease. The authors' experience with psychotherapeutic intervention and PCA support groups is shared in detail.

  10. Bilaterally impaired hand dexterity with posterior cortical atrophy

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    Nages Nagaratnam, MD, FRACP, FRCPA, FACC

    2015-12-01

    Full Text Available A 79-year- old man presented with bilaterally impaired hand movements pertaining to handling of objects although hand movements without the use of objects were preserved, findings consistent with tactile apraxia. His hand and finger movements were slow and clumsy. He had an isolated optic ataxia, a component of Balint's syndrome. The computed tomography scan showed enlargement of the posterior horns of the lateral ventricles. He had recurrent falls probably owing to visual attentional deficits, which may be present in patients with posterior cortical atrophy. The findings can be deemed to fall within the posterior cortical atrophy spectrum. The underlying mechanisms are discussed.

  11. Research progress of posterior cortical atrophy

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    Li-jun PENG

    2016-06-01

    Full Text Available Posterior cotical atrophy (PCA is a kind of progressive dementia with main clinical manifestations of visual dysfunction as the starting symptom and associated with progressive cognitive disorder. The histopathology and imaging of PCA show visual dysfunction, neuritic plaques (NPs and neurofibrillary tangles (NFTs, which are the same as those in Alzheimer's disease (AD. Researches also showed that mutation of presenilin-1 (PS-1 gene and apolipoprotein E (ApoE genotype may participate in the occurrence and development of PCA. Parieto-occipital lobe atrophy, hypoperfusion and/or glucose metabolism reduction in the right posterior cerebrum can be seen in PCA. Cholinesterase inhibitors (ChEIs may improve the symptoms and postpone the progression of illness. No unified diagnostic criteria will reduce the comparability between different studies. Reasonable usage of the diagnostic criteria of PCA will be helpful in classifying and differentiating this disease. DOI: 10.3969/j.issn.1672-6731.2016.06.011

  12. Posterior Cortical Atrophy Presenting with Superior Arcuate Field Defect

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    Sue Ling Wan

    2015-01-01

    Full Text Available An 80-year-old female with reading difficulty presented with progressive arcuate field defect despite low intraocular pressure. Over a 5-year period, the field defect evolved into an incongruous homonymous hemianopia and the repeated neuroimaging revealed progressive posterior cortical atrophy. Further neuropsychiatric assessment demonstrated symptoms and signs consistent with Benson’s syndrome.

  13. Atrofia muscular proximal familiar

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    José Antonio Levy

    1962-09-01

    Full Text Available Os autores relatam dois casos de atrofia muscular proximal familiar, moléstia caracterizada por déficit motor e atrofias musculares de distribuição proximal, secundárias a lesão de neurônios periféricos. Assim, como em outros casos descritos na literatura, foi feito inicialmente o diagnóstico de distrofia muscular progressiva. O diagnóstico correto foi conseguido com auxílio da eletromiografia e da biopsia muscular.

  14. Acute cortical blindness due to posterior reversible encephalopathy.

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    Nguyen-Lam, Jenny; Kiernan, Matthew C

    2008-10-01

    An acutely hypertensive 55 year-old male experienced seizures and cortical blindness post-operatively. CT scans demonstrated hypointensities in the occipital lobes bilaterally. MRI revealed symmetrical bilateral hyperintense signals in the same region, involving both grey and white matter. Thromboembolic screening investigations including vertebral artery doppler studies were normal and echocardiography demonstrated borderline left ventricular hypertrophy. A diagnosis of posterior reversible encephalopathy syndrome (PRES) was reached and there was complete resolution of blindness with antihypertensive therapy. This case supports the vasogenic theory of PRES which suggests that sustained high grade fluctuations in blood pressure lead to a reduction in cerebral vascular autoregulatory function. The resultant failure of compensatory vasoconstriction to prevent hyperperfusion causes fluid to extravasate into the occipital lobes, which in the present case resulted in cortical blindness.

  15. Cortical sensory loss in a patient with posterior cortical atrophy: a case report.

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    Hsu, Jung-Lung; Chen, Wei-Hung; Chiu, Hou-Chang

    2004-02-01

    Patients with posterior cortical atrophy (PCA) who present with initial symptoms of higher visual function deficits eventually develop alexia, aphasia, and components of Balint's syndrome or Gerstmann's syndrome. Recently, pathological findings were reported for these patients that are generally suggestive of Alzheimer's disease even though Creutzfeldt-Jakob disease (CJD) was presumed as an alternative cause of some autopsy-diagnosed PCA cases. Here, we report a case with a four-year progression of cognitive and higher visual function deterioration, and with features not described in previously reported PCA cases (i.e., a distinct sensory complaint and early frontal lobe involvement). To summarize, this case belongs to perceptual-motor syndrome of asymmetric cortical degeneration and the underlying neuropathology is more suggestive of Alzheimer's disease than of Creutzfeldt-Jakob disease.

  16. Basic visual function and cortical thickness patterns in posterior cortical atrophy.

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    Lehmann, Manja; Barnes, Josephine; Ridgway, Gerard R; Wattam-Bell, John; Warrington, Elizabeth K; Fox, Nick C; Crutch, Sebastian J

    2011-09-01

    Posterior cortical atrophy (PCA) is characterized by a progressive decline in higher-visual object and space processing, but the extent to which these deficits are underpinned by basic visual impairments is unknown. This study aimed to assess basic and higher-order visual deficits in 21 PCA patients. Basic visual skills including form detection and discrimination, color discrimination, motion coherence, and point localization were measured, and associations and dissociations between specific basic visual functions and measures of higher-order object and space perception were identified. All participants showed impairment in at least one aspect of basic visual processing. However, a number of dissociations between basic visual skills indicated a heterogeneous pattern of visual impairment among the PCA patients. Furthermore, basic visual impairments were associated with particular higher-order object and space perception deficits, but not with nonvisual parietal tasks, suggesting the specific involvement of visual networks in PCA. Cortical thickness analysis revealed trends toward lower cortical thickness in occipitotemporal (ventral) and occipitoparietal (dorsal) regions in patients with visuoperceptual and visuospatial deficits, respectively. However, there was also a lot of overlap in their patterns of cortical thinning. These findings suggest that different presentations of PCA represent points in a continuum of phenotypical variation.

  17. 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.

  18. Transient cortical blindness as a complication of posterior spinal surgery in a pediatric patient.

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    Nathan, Senthil T; Jain, Viral; Lykissas, Marios G; Crawford, Alvin H; West, Constance E

    2013-09-01

    Postoperative vision loss after spinal surgery is a well-known but devastating complication that may result from direct ocular ischemia, embolism to the central retinal artery, ischemic optic neuropathy, or occipital cortical ischemia. The occipital cortex is situated in the posterior border zone of the middle and posterior cerebral arteries and is susceptible to ischemic damage. Transient cortical blindness as a cause of postoperative vision loss has never been reported after spine surgery in a child. We report an 11-year-old female patient with muscular dystrophy who underwent posterior spinal fusion and instrumentation under hypotensive anesthesia for scoliosis who developed transient cortical blindness.

  19. Thalamo-cortical projections to the posterior parietal cortex in the monkey.

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    Matsuzaki, Ryuichi; Kyuhou, Shin-ichi; Matsuura-Nakao, Kazuko; Gemba, Hisae

    2004-01-23

    Thalamo-cortical projections to the posterior parietal cortex (PPC) were investigated electrophysiologically in the monkey. Cortical field potentials evoked by the thalamic stimulation were recorded with electrodes chronically implanted on the cortical surface and at a 2.0-3.0 mm cortical depth in the PPC. The stimulation of the nucleus lateralis posterior (LP), nucleus ventralis posterior lateralis pars caudalis (VPLc), and nucleus pulvinaris lateralis (Pul.l) and medialis (Pul.m) induced surface-negative, depth-positive potentials in the PPC. The LP and VPLc projected mainly to the superior parietal lobule (SPL) and the anterior bank of the intraparietal sulcus (IPS), and the Pul.m mainly to the inferior parietal lobule (IPL) and the posterior bank of the IPS. The Pul.l had projections to all of the SPL, the IPL and both the banks. The significance of the projections is discussed in connection with motor functions.

  20. Cerebello-thalamo-cortical projections to the posterior parietal cortex in the macaque monkey.

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    Amino, Y; Kyuhou, S; Matsuzaki, R; Gemba, H

    2001-08-17

    The cerebello-thalamo-posterior parietal cortical projections were investigated electrophysiologically and morphologically in macaque monkeys. In anesthetized monkeys, electrical stimulation of every cerebellar nucleus evoked marked surface-positive, depth-negative (s-P, d-N) cortical field potentials in the superior parietal lobule and the cortical bank of the intraparietal sulcus, but no responses in the inferior parietal lobule. Tract-tracing experiments combining the anterograde method with the retrograde one indicated that the interposed and lateral cerebellar nuclei projected to the posterior parietal cortex mainly through the nucleus ventral lateralis caudalis of the thalamus. The significance of the projections is discussed in connection with cognitive functions.

  1. Cortical blindness following posterior lumbar decompression and fusion.

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    Agarwal, Nitin; Hansberry, David R; Goldstein, Ira M

    2014-01-01

    Perioperative vision loss following non-ocular surgery is a well-documented phenomenon. In particular, perioperative vision loss has been frequently cited following spinal surgery. Although the rate of vision compromise in spinal surgery is relatively low, the consequences can be quite severe and devastating for the patient. We report a 60-year-old woman who initially presented with back and left leg pain as well as paraparesis. Imaging studies of the lumbar spine showed bony erosion consistent with tumor infiltration of the L3 and L4 spinal segments. Laminectomy at the L2-L4 levels for decompression of the intraspinal tumor was performed. Pathology of the resected bone was consistent with metastatic adenocarincoma. Postoperatively, the patient suffered severe anemia and bilateral infarctions of the posterior cerebral arteries and occipital lobes resulting in vision compromise. Although a definitive pathogenesis remains unknown, preoperative cardiovascular issues and intraoperative hemodynamic instabilities have typically been implicated as high risk factors. High risk factors for this novel clinical presentation of visual compromise following posterior lumbar laminectomy with decompression for an intraspinal tumor are reported.

  2. Cortical blindness and posterior reversible encephalopathy syndrome in an older patient.

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    Ait, Sabrina; Gilbert, Thomas; Cotton, Francois; Bonnefoy, Marc

    2012-05-26

    Posterior reversible encephalopathy syndrome (PRES) is a clinical and radiological entity. It associates, to varying extents, neurological symptoms such as headaches, confusion, seizures and visual alterations from haemianopsia to cortical blindness. The diagnosis relies on brain MRI, showing signs of subcortical and cortical oedema in the posterior regions of the brain, with hypersignals in T2/fluid attenuated inversion recovery (FLAIR) or diffusion sequences. With early diagnosis and control of the causal factors, the symptoms and radiological signs can be - as the name implies - totally regressive. PRES can be caused by various heterogeneous factors, such as hypertension, side effect of drug therapies, eclampsia, sepsis or autoimmune diseases. The authors report here the case of an 86-year-old woman, presenting totally regressive cortical blindness and seizures, with compatible imaging.

  3. Permanent bilateral cortical blindness due to reversible posterior leukoencephalopathy syndrome.

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    Iwama, Mayumi; Takahashi, Hiroshi; Takagi, Ryo; Hiraoka, Miki

    2011-01-01

    Reversible posterior leukoencephalopathy syndrome (RPLS) is induced by acute cerebral edema. Its symptoms include seizures, headache, altered mental status, and visual disturbances. The clinical and radiological findings are usually transient. This report describes a case of RPLS resulting in bilateral total blindness. A 40-year-old man presented with lethargy and bilateral visual loss. He had a 20-year history of hypertension, but had never been treated. On presentation, the left eye was able to perceive light, but the right eye was not. Radiological examination showed diffuse edema in the brain, and ocular fundus examination revealed severe bilateral hypertensive retinopathy. Antihypertensive therapy improved the patient's general condition, including blood pressure. Radiological findings 5 months later showed resolution of most of the abnormal signal areas. However, total blindness had developed in both eyes by day 15, and two courses of pulsed corticosteroid therapy failed to restore the visual loss.

  4. Cortical damage in the posterior visual pathway in patients with sialidosis type 1.

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    Lu, Chin-Song; Ng, Shu-Hang; Lai, Szu-Chia; Kao, Ling-Yuh; Liu, Laura; Lin, Wey-Yil; Wu, Yi-Ming; Chen, Yao-Liang; Wang, Jiun-Jie

    2016-02-03

    In order to identify the cortical changes in patients with Sialidosis type 1, diffusion tensor imaging and resting state fMRI were acquired from 11 patients and 11 sex/age matched normal controls after clinical evaluations. The neuroimages from each participant were normalized and parcellated according to the Automatic Anatomical Labeling. Both the mean diffusivity and the corresponding functional connectivity were calculated from each cortical region. The white matter tract integrity was examined. The difference between patients and controls was examined using Student's t-test and between patients with either homozygous or heterozygous mutations by Mann-Whitney U test, both at a threshold of 0.05. Increased mean diffusivity throughout the brain can be noticed in the patients, together with a compromised white matter tracts integrity. The most severely affected cortical regions are in the occipital lobe. Decreased functional connectivity was from the temporal and occipital lobes to the hippocampus and parahippocampus. In contrast, connectivity from thalamus was enhanced. Diffused cortical atrophy with posterior focal lesions was noticed. We concluded that MRI observed functional changes in the posterior cortical pathways in the patients with Sialidosis. The observation might be related to the cortical blindness due to an altered neural network and a compromised visual pathway in the patients.

  5. [Familial posterior cortical atrophy with visual agnosia and Bálint's syndrome].

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    Otsuki, M; Soma, Y; Tanaka, M; Tanaka, K; Tanno, Y; Uesugi, Y; Tsuji, S

    1995-12-01

    We report a patient of posterior cortical atrophy with progressive visual agnosia, Bálint's syndrome and dementia in which posterior cortical atrophy with similar characteristics on CT and progressive dementia were found in a sister. The patient was a 75-year-old woman who noted the onset of a progressive visual disorder at the age of 70, and whose family first noticed disoriented behavior at around the same period. Ophthalmologic examinations revealed mild cataract but no evidence of peripheral optic nerve or retinal lesions. Neuropsychological examination showed right homonymous hemianopia, visual agnosia, Bálint's syndrome, mild transcortical sensory aphasia, Gerstmann's syndrome, constructional apraxia, mild ideomotor apraxia and memory disorder. MRI showed marked dilatation of both lateral ventricles, especially the posterior horns, and severe atrophy of the occipital lobes, hippocampus, and the parahippocampal gyrus. Assessment of regional cerebral blood flow by IMP-SPECT revealed a generalized decrease in the temporo-parieto-occipital region bilaterally. The patient's sister began to show evidence of progressive dementia at 80 years of age and CT of the brain revealed marked atrophy, predominantly in the occipital lobes, similar to that of the patient. We believe this to be the first report of posterior cortical atrophy with a positive family history, suggesting the possibility of a hereditary syndrome.

  6. Control of Somatosensory Cortical Processing by Thalamic Posterior Medial Nucleus: A New Role of Thalamus in Cortical Function.

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    Carlos Castejon

    Full Text Available Current knowledge of thalamocortical interaction comes mainly from studying lemniscal thalamic systems. Less is known about paralemniscal thalamic nuclei function. In the vibrissae system, the posterior medial nucleus (POm is the corresponding paralemniscal nucleus. POm neurons project to L1 and L5A of the primary somatosensory cortex (S1 in the rat brain. It is known that L1 modifies sensory-evoked responses through control of intracortical excitability suggesting that L1 exerts an influence on whisker responses. Therefore, thalamocortical pathways targeting L1 could modulate cortical firing. Here, using a combination of electrophysiology and pharmacology in vivo, we have sought to determine how POm influences cortical processing. In our experiments, single unit recordings performed in urethane-anesthetized rats showed that POm imposes precise control on the magnitude and duration of supra- and infragranular barrel cortex whisker responses. Our findings demonstrated that L1 inputs from POm imposed a time and intensity dependent regulation on cortical sensory processing. Moreover, we found that blocking L1 GABAergic inhibition or blocking P/Q-type Ca2+ channels in L1 prevents POm adjustment of whisker responses in the barrel cortex. Additionally, we found that POm was also controlling the sensory processing in S2 and this regulation was modulated by corticofugal activity from L5 in S1. Taken together, our data demonstrate the determinant role exerted by the POm in the adjustment of somatosensory cortical processing and in the regulation of cortical processing between S1 and S2. We propose that this adjustment could be a thalamocortical gain regulation mechanism also present in the processing of information between cortical areas.

  7. Control of Somatosensory Cortical Processing by Thalamic Posterior Medial Nucleus: A New Role of Thalamus in Cortical Function

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    Castejon, Carlos; Barros-Zulaica, Natali; Nuñez, Angel

    2016-01-01

    Current knowledge of thalamocortical interaction comes mainly from studying lemniscal thalamic systems. Less is known about paralemniscal thalamic nuclei function. In the vibrissae system, the posterior medial nucleus (POm) is the corresponding paralemniscal nucleus. POm neurons project to L1 and L5A of the primary somatosensory cortex (S1) in the rat brain. It is known that L1 modifies sensory-evoked responses through control of intracortical excitability suggesting that L1 exerts an influence on whisker responses. Therefore, thalamocortical pathways targeting L1 could modulate cortical firing. Here, using a combination of electrophysiology and pharmacology in vivo, we have sought to determine how POm influences cortical processing. In our experiments, single unit recordings performed in urethane-anesthetized rats showed that POm imposes precise control on the magnitude and duration of supra- and infragranular barrel cortex whisker responses. Our findings demonstrated that L1 inputs from POm imposed a time and intensity dependent regulation on cortical sensory processing. Moreover, we found that blocking L1 GABAergic inhibition or blocking P/Q-type Ca2+ channels in L1 prevents POm adjustment of whisker responses in the barrel cortex. Additionally, we found that POm was also controlling the sensory processing in S2 and this regulation was modulated by corticofugal activity from L5 in S1. Taken together, our data demonstrate the determinant role exerted by the POm in the adjustment of somatosensory cortical processing and in the regulation of cortical processing between S1 and S2. We propose that this adjustment could be a thalamocortical gain regulation mechanism also present in the processing of information between cortical areas. PMID:26820514

  8. Pronounced Impairment of Everyday Skills and Self-Care in Posterior Cortical Atrophy.

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    Shakespeare, T. J.; Yong, K. X.; Foxe, D.; Hodges, J.; Crutch, S. J.

    2014-01-01

    Posterior cortical atrophy (PCA) is a neurodegenerative syndrome characterized by progressive visual dysfunction and parietal, occipital, and occipitotemporal atrophy. The aim of this study was to compare the impact of PCA and typical Alzheimer's disease (tAD) on everyday functional abilities and neuropsychiatric status. The Cambridge Behavioural Inventory-Revised was given to carers of 32 PCA and 71 tAD patients. PCA patients showed significantly greater impairment in everyday skills and sel...

  9. Can patients without early, prominent visual deficits still be diagnosed of posterior cortical atrophy?

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    Suárez-González, A.; Crutch, S.J.; Roldán Lora, F.; Franco-Macías, E.; Gil-Néciga, E.

    2016-01-01

    Background Early and progressive disabling visual impairment is a core feature for the diagnosis of posterior cortical atrophy (PCA). However, some individuals that fulfil criteria over time might initially present with an onset of prominent posterior dysfunction other than visuoperceptual. Methods The clinical profile of five patients with a predominantly ‘non-visual’ posterior presentation (PCA2) was investigated and compared with sixteen individuals with visually predominant PCA (PCA1) and eighteen with typical amnestic Alzheimer disease (tAD). Results PCA2 patients showed significantly better performance than PCA1 in one visuospatial task and were free of Balint's syndrome and visual agnosia. Compared to tAD, PCA2 showed trends towards significantly lower performance in visuoperceptual tasks, more severe apraxia and more symptoms of Gerstmann's syndrome. Conclusions Our sample of PCA2 patients did not present with clinically prominent visual symptoms but did show visual dysfunction on formal neuropsychological assessment (less pronounced than in PCA1 but more than in tAD) in addition to other posterior deficits. Broadening the definition of PCA to encompass individuals presenting with prominent ‘non-visual’ posterior dysfunction should be potentially considered in clinical and research contexts. PMID:27423559

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

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    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.)

  11. Genetic risk factors for the posterior cortical atrophy variant of Alzheimer's disease

    OpenAIRE

    Schott, Jonathan M.; Crutch, Sebastian J.; Carrasquillo, Minerva M.; Uphill, James; Shakespeare, Tim J.; Ryan, Natalie S; Yong, Keir X. X.; Lehmann, Manja; Ertekin-Taner, Nilufer; Graff-Radford, Neil R.; Boeve, Bradley F.; Murray, Melissa E.; Khan, Qurat ul Ain; Petersen, Ronald C.; Dickson, Dennis W.

    2016-01-01

    INTRODUCTION: The genetics underlying posterior cortical atrophy (PCA), typically a rare variant of Alzheimer's disease (AD), remain uncertain.METHODS: We genotyped 302 PCA patients from 11 centers, calculated risk at 24 loci for AD/DLB and performed an exploratory genome-wide association study.RESULTS: We confirm that variation in/near APOE/TOMM40 (P = 6 × 10(-14)) alters PCA risk, but with smaller effect than for typical AD (PCA: odds ratio [OR] = 2.03, typical AD: OR = 2.83, P = .0007). We...

  12. Different levels of implicit emotional recognition in posterior cortical atrophy (PCA).

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    Gonzalez-Gadea, María Luz; Ibanez, Agustín; Damm, Juliane; Ramirez Romero, Diana Andrea; Abrevaya, Sofia; Manes, Facundo; Richly, Pablo; Roca, Maria

    2015-01-01

    Previous single-case reports in posterior cortical atrophy (PCA) have shown preserved nonconscious visual recognition despite the absence of explicit recognition. In this study, we investigated three levels of visual recognition in both a female patient with PCA and a control group during the presentation of neutral, positive, and negative affective stimuli. Our results confirmed the profile of impaired explicit recognition and intact psychophysiological responses in the patient. In addition, she was able to implicitly recognize the valence and intensity of arousal of these stimuli. We suggest that implicit emotional awareness may mediates explicit and psychophysiological recognition in PCA.

  13. The Evolution of Alexia in Two Cases of Posterior Cortical Atrophy

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    Eleonora Catricalà

    2011-01-01

    Full Text Available Posterior cortical atrophy (PCA is an uncommon presentation of Alzheimer's disease (AD, characterised by prevalent anatomo-functional involvement of posterior cortical areas. Accordingly, the main clinical features at onset are disorders of high-order visual processing, such as alexia and impairments of visuo-spatial and visuo-constructional abilities. The clinical features in the early stages of disease are variable, and they have been suggested to stem from prevalent ventral or dorsal brain pathology, and/or asymmetric hemispheric involvement. With disease progression, these differences tend to blur with the increasing severity of neuropsychological dysfunction. We report two PCA patients showing different patterns of reading impairment (respectively, letter-by-letter reading and neglect dyslexia. A follow-up study suggested that the qualitative features of alexia remain distinctive with disease evolution. In addition, single photon emission tomography (SPECT studies revealed different patterns of hypoperfusion, consistent with the alexia types. A careful reading assessment can provide important insights to the pattern of progression of the disease in patients with PCA up to the late stages of the pathology.

  14. Desarrollo neuromuscular en la atrofia muscular espinal

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    Martínez Hernàndez, Rebeca

    2012-01-01

    INTRODUCCIÓN: La atrofia muscular espinal (AME) es una enfermedad neuromuscular infantil caracterizada por la muerte de las neuronas motoras del asta anterior de la médula espinal. Como consecuencia de ello hay una degeneración y atrofia muscular, por lo que los pacientes mueren a menudo de insuficiencias respiratorias graves. La AME se clasifica en tres tipos principales según el grado de gravedad, la edad de aparición y las pautas motoras. Se trata de una enfermedad con patrón de herencia a...

  15. Usefulness of Multi-Parametric MRI for the Investigation of Posterior Cortical Atrophy.

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    Andrea Arighi

    Full Text Available Posterior Cortical Atrophy (PCA is a neurodegenerative disease characterized by a progressive decline in selective cognitive functions anatomically referred to occipital, parietal and temporal brain regions, whose diagnosis is rather challenging for clinicians. The aim of this study was to assess, using quantitative Magnetic Resonance Imaging techniques, the pattern of regional grey matter loss and metabolism in individuals with PCA to improve pathophysiological comprehension and diagnostic confidence.We enrolled 5 patients with PCA and 5 matched controls who all underwent magnetic resonance imaging (MRI and spectroscopy (MRS. Patients also underwent neuropsychological and cerebrospinal fluid (CSF assessments. MRI data were used for unbiased assessment of regional grey matter loss in PCA patients compared to controls. MRS data were obtained from a set of brain regions, including the occipital lobe and the centrum semiovale bilaterally, and the posterior and anterior cingulate.VBM analysis documented the presence of focal brain atrophy in the occipital lobes and in the posterior parietal and temporal lobes bilaterally but more pronounced on the right hemisphere. MRS revealed, in the occipital lobes and in the posterior cingulate cortex of PCA patients, reduced levels of N-Acetyl Aspartate (NAA, a marker of neurodegeneration and increased levels of Myo-Inositol (Ins, a glial marker, with no hemispheric lateralization.The bilateral but asymmetric pattern of regional grey matter loss is consistent with patients' clinical and neuropsychological features and with previous literature. The MRS findings reveal different stages of neurodegeneration (neuronal loss; gliosis, which coexist and likely precede the occurrence of brain tissue loss, and might represent early biomarkers. In conclusion, this study indicates the potential usefulness of a multi-parametric MRI approach for an early diagnosis and staging of patients with PCA.

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

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    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.

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

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    Simona Gardini

    2011-01-01

    Full Text Available 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, topographical disorientation with way-finding deficits, impaired map learning and poor mental image generation. Semantic memory was normal, while episodic-autobiographical memory was impaired. Reduced rCBF was found mainly in the right hemisphere, in the precentral gyrus, posterior cingulate and middle temporal gyri, cuneus and precuneus, in the left superior temporal and lingual gyri and in the parahippocampus bilaterally. Hypoperfusion in occipito-parietal regions was associated with visuo-spatial deficits, whereas deficits in visuo-spatial mental imagery might reflect dysfunction related to hypoperfusion in the parahippocampus and precuneus, structures which are responsible for spatial and imagery processing. Dissociating performance between preserved semantic memory and poor episodic-autobiographical recall is consistent with a pattern of normal perfusion in frontal and anterior temporal regions but abnormal rCBF in the parahippocampi. The present findings indicate that PCA involves visuo-spatial imagery deficits and provide further validation to current neuro-cognitive models of spatial representation and topographical disorientation.

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

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    Benjamin P Meek

    2013-06-01

    Full Text Available 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 characterized by atrophy in occipito-parietal and occipito-temporal cortices. PCA primarily affects higher visual processing, while memory, reasoning, and insight remain relatively intact. A common symptom of PCA is a decreased effective field of vision caused by the inability to ‘see the whole picture’. Individuals with PCA and healthy control participants completed a same/different discrimination task in which images of faces were presented as cue-target pairs. Eye-tracking equipment and a novel computer-based perceptual task – the Viewing Window paradigm – were used to investigate scan patterns when faces were presented in open view or through a restricted-view, respectively. In contrast to previous prosopagnosia research, individuals with PCA each produced unique scan paths that focused on non-diagnostically useful locations. This focus on non-diagnostically useful locations was also present when using a restricted viewing aperture, suggesting that individuals with PCA have difficulty processing the face at either the featural or configural level. In fact, it appears that the decreased effective field of view in PCA patients is so severe that it results in an extreme dependence on local processing, such that a feature-based approach is not even possible.

  19. Somatosensory-motor adaptation of orofacial actions in posterior parietal and ventral premotor cortices.

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    Krystyna Grabski

    Full Text Available Recent studies have provided evidence for sensory-motor adaptive changes and action goal coding of visually guided manual action in premotor and posterior parietal cortices. To extend these results to orofacial actions, devoid of auditory and visual feedback, we used a repetition suppression paradigm while measuring neural activity with functional magnetic resonance imaging during repeated intransitive and silent lip, jaw and tongue movements. In the motor domain, this paradigm refers to decreased activity in specific neural populations due to repeated motor acts and has been proposed to reflect sensory-motor adaptation. Orofacial movements activated a set of largely overlapping, common brain areas forming a core neural network classically involved in orofacial motor control. Crucially, suppressed neural responses during repeated orofacial actions were specifically observed in the left ventral premotor cortex, the intraparietal sulcus, the inferior parietal lobule and the superior parietal lobule. Since no visual and auditory feedback were provided during orofacial actions, these results suggest somatosensory-motor adaptive control of intransitive and silent orofacial actions in these premotor and parietal regions.

  20. Differential roles of the dorsal prefrontal and posterior parietal cortices in visual search: a TMS study.

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    Yan, Yulong; Wei, Rizhen; Zhang, Qian; Jin, Zhenlan; Li, Ling

    2016-07-25

    Although previous studies have shown that fronto-parietal attentional networks play a crucial role in bottom-up and top-down processes, the relative contribution of the frontal and parietal cortices to these processes remains elusive. Here we used transcranial magnetic stimulation (TMS) to interfere with the activity of the right dorsal prefrontal cortex (DLPFC) or the right posterior parietal cortex (PPC), immediately prior to the onset of the visual search display. Participants searched a target defined by color and orientation in "pop-out" or "search" condition. Repetitive TMS was applied to either the right DLPFC or the right PPC on different days. Performance was evaluated at baseline (no TMS), during TMS, and after TMS (Post-session). RTs were prolonged when TMS was applied over the DLPFC in the search, but not in the pop-out condition, relative to the baseline session. In comparison, TMS over the PPC prolonged RTs in the pop-out condition, and when the target appeared in the left visual field for the search condition. Taken together these findings provide evidence for a differential role of DLPFC and PPC in the visual search, indicating that DLPFC has a specific involvement in the "search" condition, while PPC is mainly involved in detecting "pop-out" targets.

  1. The oral spelling profile of posterior cortical atrophy and the nature of the graphemic representation.

    Science.gov (United States)

    Primativo, Silvia; Yong, Keir X X; Shakespeare, Timothy J; Crutch, Sebastian J

    2017-01-08

    Spelling is a complex cognitive task where central and peripheral components are involved in engaging resources from many different cognitive processes. The present paper aims to both characterize the oral spelling deficit in a population of patients affected by a neurodegenerative condition and to clarify the nature of the graphemic representation within the currently available spelling models. Indeed, the nature of graphemic representation as a linear or multi-componential structure is still debated. Different hypotheses have been raised about its nature in the orthographic lexicon, with one positing that graphemes are complex objects whereby quantity and identity are separately represented in orthographic representations and can thus be selectively impaired. Posterior cortical atrophy (PCA) is a neurodegenerative condition that mainly affects visuoperceptual and visuospatial functions. Spelling impairments are considered part of the disease. Nonetheless the spelling deficit has received little attention so far and often it has been interpreted in relation to peripheral impairments such as writing difficulties associated with visuoperceptual and visuospatial deficits. In the present study we provide a detailed characterization of the oral spelling profile in PCA. The data suggest that multiple deficits underpin oral spelling problems in PCA, with elements of surface and phonological dysgraphia but also suggesting the involvement of the graphemic buffer. A large phenotypic individual variability is reported. Moreover, the larger proportion and the specific nature of errors involving geminate (i.e., double) as compared to non-geminate (i.e., non-double) letters suggest that a further central impairment might be associated with the abstract graphemic representation of letter numerosity. The present study contributes to the clinical characterization of PCA and to the current debate in the cognitive literature on spelling models; findings, despite not definitive

  2. 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.

  3. 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.

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

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    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

  5. Remodeling of heat-treated cortical bone allografts for posterior lumbar interbody fusion: serial 10-year follow-up.

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    Muramatsu, Koichi; Hachiya, Yudo; Izawa, Hiroyuki; Yamada, Harumoto

    2012-12-01

    We have selected heat-treated bone allografts as the graft material since the Tokai Bone Bank, the first regional bone bank in Japan, was established in 1992. In this study, we examined changes in bone mineral density (BMD), and morphology observed by magnetic resonance imaging (MRI), and histological findings of bone grafts in cases followed up for 7-10 years after bone grafting to grasp the remodeling of heat-treated cortical bone allografts for posterior lumber interbody fusion (PLIF). BMD of bone grafts was reduced by half at 10 years after grafting. MRI revealed that bone grafts were indistinguishable initially in only 22.2% of cases, whereas after a lengthy period of 10 years distinguishable in many cases. Histologically, new bone formation at the graft-host interface was observed earlier, at 1 year after grafting, than that at the periphery of canals in the specimens. The laminated structure of the cortical bone eroded over time, and fragmented bone trabeculae were observed in the specimens at 8 years or longer after grafting, though necrotic bone still remained in some sites.

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

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    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.

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

    Science.gov (United States)

    Caixeta, Leonardo Ferreira; Taleb, Alexandre Chater; Ghini, Bruno Galafassi; Soares, Vânia Lúcia Dias; Caixeta, Victor de Melo; Vargas, Ciro

    2013-10-01

    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 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.

  8. A Pilot Study on Clinical and Neuroimaging Characteristics of Chinese Posterior Cortical Atrophy: Comparison with Typical Alzheimer's Disease.

    Science.gov (United States)

    Wang, Xiao-Dan; Lu, Hui; Shi, Zhihong; Cai, Li; Liu, Shuai; Liu, Shuling; Han, Tong; Wang, Ying; Zhou, Yuying; Wang, Xinping; Gao, Shuo; Ji, Yong

    2015-01-01

    Posterior cortical atrophy (PCA) is a clinicoradiologic neurodegenerative syndrome characterized by predominant impairment of higher visual functions. Neuroimaging and neuropathological studies show that PCA is probably an atypical presentation of Alzheimer's disease. However, in China PCA has rarely been studied and remains largely unknown. Our study therefore aimed to analyze the clinical manifestations and patterns of cerebral atrophy, amyloid beta deposition and regional glucose metabolism in Chinese PCA patients, comparing them directly with those of typical Alzheimer's disease (TAD). Seven PCA patients, 6 TAD patients and 5 controls underwent neuropsychological assessment, MRI scan, 11C-PIB PET scan and 18F-FDG PET scan. Cerebral atrophy including ventricular enlargement, posterior atrophy and medial temporal lobe atrophy were evaluated with MRI. The uptake of 11C-PIB was quantified at the voxel level using the standardized uptake value ratio. Comparisons of regional cerebral glucose metabolism were calculated with statistical parametric mapping. PCA patients showed significant impairment on visuospatial function in neuropsychological assessment. And PCA patients showed more severe posterior atrophy and less severe left medial temporal lobe atrophy compared with TAD patients. The data from 11C-PIB PET scanning showed that amyloid beta deposition in PCA was comparable to TAD. Moreover, in PCA the results from 18F-FDG PET scanning revealed significant hypometabolism in the temporoparietooccipital region and identified specific hypometabolism in the right occipital lobe, compared with TAD. Our study thus provides a preliminary view of PCA in Chinese patients. A further study with a larger number of subjects would be recommended to confirm these findings.

  9. Posterior lumbar interbody fusion with cortical bone trajectory screw fixation versus posterior lumbar interbody fusion using traditional pedicle screw fixation for degenerative lumbar spondylolisthesis: a comparative study.

    Science.gov (United States)

    Sakaura, Hironobu; Miwa, Toshitada; Yamashita, Tomoya; Kuroda, Yusuke; Ohwada, Tetsuo

    2016-11-01

    OBJECTIVE Several biomechanical studies have demonstrated the favorable mechanical properties of the cortical bone trajectory (CBT) screw. However, no reports have examined surgical outcomes of posterior lumbar interbody fusion (PLIF) with CBT screw fixation for degenerative spondylolisthesis (DS) compared with those after PLIF using traditional pedicle screw (PS) fixation. The purposes of this study were thus to elucidate surgical outcomes after PLIF with CBT screw fixation for DS and to compare these results with those after PLIF using traditional PS fixation. METHODS Ninety-five consecutive patients underwent PLIF with CBT screw fixation for DS (CBT group; mean followup 35 months). A historical control group consisted of 82 consecutive patients who underwent PLIF with traditional PS fixation (PS group; mean follow-up 40 months). Clinical status was assessed using the Japanese Orthopaedic Association (JOA) scale score. Fusion status was assessed by dynamic plain radiographs and CT. The need for additional surgery and surgery-related complications was also evaluated. RESULTS The mean JOA score improved significantly from 13.7 points before surgery to 23.3 points at the latest follow-up in the CBT group (mean recovery rate 64.4%), compared with 14.4 points preoperatively to 22.7 points at final follow-up in the PS group (mean recovery rate 55.8%; p fusion was achieved in 84 patients from the CBT group (88.4%) and in 79 patients from the PS group (96.3%, p > 0.05). Symptomatic adjacent-segment disease developed in 3 patients from the CBT group (3.2%) compared with 9 patients from the PS group (11.0%, p fusion rate tended to be lower in the CBT group than in the PS group, although the difference was not statistically significant between the 2 groups.

  10. Expression of macrophage migration inhibitory factor in the mouse neocortex and posterior piriform cortices during postnatal development.

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    Zhang, Wei; Li, Lingling; Wang, Jiutao; An, Lei; Hu, Xinde; Xie, Jiongfang; Yan, Runchuan; Chen, Shulin; Zhao, Shanting

    2014-11-01

    Macrophage migration inhibitory factor (MIF) functions as a pleiotropic protein, participating in a vast array of cellular and biological processes. Abnormal expression of MIF has been implicated in many neurological diseases, including Parkinson's disease, epilepsy, Alzheimer's Disease, stroke, and neuropathic pain. However, the expression patterns of mif transcript and MIF protein from the early postnatal period through adulthood in the mouse brain are still poorly understood. We therefore investigated the temporal and spatial expression of MIF in the mouse neocortex during postnatal development in detail and partially in posterior piriform cortices (pPC). As determined by quantitative real-time PCR (qPCR), mif transcript gradually increased during development, with the highest level noted at postnatal day 30 (P30) followed by a sharp decline at P75. In contrast, Western blotting results showed that MIF increased constantly from P7 to P75. The highest level of MIF was at P75, while the lowest level of MIF was at P7. Immunofluorescence histochemistry revealed that MIF-immunoreactive (ir) cells were within the entire depth of the developed neocortex, and MIF was heterogeneously distributed among cortical cells, especially at P7, P14, P30, and P75; MIF was abundant in the pyramidal layer within pPC. Double immunostaining showed that all the mature neurons were MIF-ir and all the intensely stained MIF-ir cells were parvalbumin positive (Pv +) at adult. Moreover, it was demonstrated that MIF protein localized in the perikaryon, processes, presynaptic structures, and the nucleus in neurons. Taken together, the developmentally regulated expression and the subcellular localization of MIF should form a platform for an analysis of MIF neurodevelopmental biology and MIF-related nerve diseases.

  11. The syndrome of progressive posterior cortical dysfunction: A multiple case study and review

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    Renata Areza-Fegyveres

    Full Text Available Abstract Dementia presenting with prominent higher order visual symptoms may be observed in a range of neurodegenerative conditions and is often challenging to diagnose. Objectives: To describe cases of progressive dementia presenting with prominent visual cortical symptoms. Methods: We conducted a retrospective search of cases of progressive dementia with predominant visual symptoms, seen at our dementia unit from 1996 to 2006. Results: Twelve patients (5 men, 7 women were identified, with ages ranging from 49 to 67 years. At the first examination, the duration of the symptoms ranged from one to ten years and the Mini-Mental State Examination scores from 7 to 27. Eleven patients presented with predominant visuospatial symptoms (partial or complete Balint syndrome and one with visuoperceptive impairment. Other reported manifestations were: constructional apraxia in 11 patients, partial or complete Gerstmann syndrome in ten, ideomotor apraxia in nine, hemineglect or extinction in four patients, alien hand phenomenon in three, and prosopagnosia in one patient. Memory loss was reported by ten patients, but was not the main complaint in any of these cases. Insight was relatively preserved in five patients even after a long period following the onset of symptoms. Six patients developed parkinsonism during evolution. Clinical diagnoses were possible or probable AD in seven patients, cortico-basal degeneration in four, and dementia with Lewy body in one. Conclusions: Clinicians 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.

  12. Atrofia girata de coróide e retina : relato de caso

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    Oyamaguchi Emerson Kenji

    2003-01-01

    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.

  13. The relationship between visual crowding and letter confusability: towards an understanding of dyslexia in posterior cortical atrophy.

    Science.gov (United States)

    Crutch, Sebastian J; Warrington, Elizabeth K

    2009-07-01

    Visual crowding is a form of masking in which target identification is hindered by excessive feature integration from other stimuli in the vicinity. It has previously been suggested that excessive visual crowding constitutes one specific form of early-visual-processing deficit, which may be observed in individuals with posterior cortical atrophy (PCA). This study investigated whether excessive visual crowding plays a significant role in the acquired dyslexia of two PCA patients, whose reading was characterized by visual paralexias. The patients were administered a series of letter, flanked letter, and word recognition tasks, and the effects of letter spacing and letter confusability upon response accuracy and latency were measured. In both patients, the results showed (a) evidence of excessive visual crowding, (b) a significant interaction between letter spacing and confusability on flanked letter identification tasks, and (c) effects of letter confusability affecting flanked but not unflanked letter identification. However, only mild improvements in reading accuracy were achieved in the experimental manipulations of interletter spacing within words because these manipulations had a dual effect: Increasing spacing improved individual letter identification but damaged whole-word form and/or parallel letter processing. We consider the implications of these results for the characterization of dyslexia in PCA, the design of reading rehabilitation strategies, and the relationship between visual crowding and letter confusability. In particular, we argue that the reading deficits observed in our patients cannot be accounted for solely in terms of a very low signal-to-noise ratio for letter identification, and that an additional crowding deficit is implicated in which excessive integration of fundamental letter features leads to the formation of incorrect letter percepts.

  14. Atrofia de íris após tratamento estético facial com luz intensa pulsada

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    Ângelo Ferreira Passos

    2012-06-01

    Full Text Available Relato de um caso de complicação ocular, em consequência do uso de luz intensa pulsada, para tratamento facial cosmético. A lesão consistiu em atrofia iriana no setor temporal, com grande área de transiluminação, sinéquias posteriores, deformidade e redução da dilatação pupilar. O objetivo é alertar para os riscos do procedimento para os olhos, caso não sejam tomadas as medidas adequadas de proteção ocular.

  15. Resúmenes de los trabajos sobre la atrofia espinocerebelosa

    OpenAIRE

    2010-01-01

    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 inves...

  16. Resúmenes de los trabajos sobre la atrofia espinocerebelosa

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    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.

  17. Cortical blindness after contrast-enhanced CT scan in a patient of sarcoidosis - Is it related to posterior reversible encephalopathy syndrome?

    Science.gov (United States)

    Suri, Vinit; Agarwal, Ritu; Jadhao, Nilesh; Ahuja, Gulshan K

    2011-10-01

    Transient cortical blindness (TCB) is a well known but rare complication of administration of contrast agent. In this case report, we present a 53-year-old woman who is a follow-up case of sarcoidosis and developed TCB with focal neurological symptoms following contrast-enhanced computed tomography scan. Magnetic resonance imaging revealed bilateral T2/Flair hyperintensities in parieto-occipital, high frontal, and cerebellar hemispheres with involvement of corpus callosum. Clinically and radiologically patient improved significantly in 4 days. The exact mechanism is still speculative and its possible relationship with posterior reversible encephalopathy syndrome is briefly discussed. The patient's symptoms were presumed to be exacerbated by presence of hypertension, underlying autoimmune disorder, sepsis, and high osmolality of contrast agent. Though there is no definite evidence to suggest that a certain treatment regimen improves the natural history of this disease but control of risk factors can possibly prevent this rare but devastating complication.

  18. Cortical blindness after contrast-enhanced CT scan in a patient of sarcoidosis - Is it related to posterior reversible encephalopathy syndrome?

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    Vinit Suri

    2011-01-01

    Full Text Available Transient cortical blindness (TCB is a well known but rare complication of administration of contrast agent. In this case report, we present a 53-year-old woman who is a follow-up case of sarcoidosis and developed TCB with focal neurological symptoms following contrast-enhanced computed tomography scan. Magnetic resonance imaging revealed bilateral T2/Flair hyperintensities in parieto-occipital, high frontal, and cerebellar hemispheres with involvement of corpus callosum. Clinically and radiologically patient improved significantly in 4 days. The exact mechanism is still speculative and its possible relationship with posterior reversible encephalopathy syndrome is briefly discussed. The patient′s symptoms were presumed to be exacerbated by presence of hypertension, underlying autoimmune disorder, sepsis, and high osmolality of contrast agent. Though there is no definite evidence to suggest that a certain treatment regimen improves the natural history of this disease but control of risk factors can possibly prevent this rare but devastating complication.

  19. Different cortical projections from three subdivisions of the rat lateral posterior thalamic nucleus: a single-neuron tracing study with viral vectors.

    Science.gov (United States)

    Nakamura, Hisashi; Hioki, Hiroyuki; Furuta, Takahiro; Kaneko, Takeshi

    2015-05-01

    The lateral posterior thalamic nucleus (LP) is one of the components of the extrageniculate pathway in the rat visual system, and is cytoarchitecturally divided into three subdivisions--lateral (LPl), rostromedial (LPrm), and caudomedial (LPcm) portions. To clarify the differences in the dendritic fields and axonal arborisations among the three subdivisions, we applied a single-neuron labeling technique with viral vectors to LP neurons. The proximal dendrites of LPl neurons were more numerous than those of LPrm and LPcm neurons, and LPrm neurons tended to have wider dendritic fields than LPl neurons. We then analysed the axonal arborisations of LP neurons by reconstructing the axon fibers in the cortex. The LPl, LPrm and LPcm were different from one another in terms of the projection targets--the main target cortical regions of LPl and LPrm neurons were the secondary and primary visual areas, whereas those of LPcm neurons were the postrhinal and temporal association areas. Furthermore, the principal target cortical layers of LPl neurons in the visual areas were middle layers, but that of LPrm neurons was layer 1. This indicates that LPl and LPrm neurons can be categorised into the core and matrix types of thalamic neurons, respectively, in the visual areas. In addition, LPl neurons formed multiple axonal clusters within the visual areas, whereas the fibers of LPrm neurons were widely and diffusely distributed. It is therefore presumed that these two types of neurons play different roles in visual information processing by dual thalamocortical innervation of the visual areas.

  20. The Pattern of Brain Amyloid Load in Posterior Cortical Atrophy Using 18F-AV45: Is Amyloid the Principal Actor in the Disease

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    Emilie Beaufils

    2014-11-01

    Full Text Available Background: Posterior cortical atrophy (PCA is characterized by progressive higher-order visuoperceptual dysfunction and praxis declines. This syndrome is related to a number of underlying diseases, including, in most cases, Alzheimer's disease (AD. The aim of this study was to compare the amyloid load with 18F-AV45 positron emission tomography (PET between PCA and AD subjects. Methods: We performed 18F-AV45 PET, cerebrospinal fluid (CSF biomarker analysis and a neuropsychological assessment in 11 PCA patients and 12 AD patients. Results: The global and regional 18F-AV45 uptake was similar in the PCA and AD groups. No significant correlation was observed between global 18F-AV45 uptake and CSF biomarkers or between regional 18F-AV45 uptake and cognitive and affective symptoms. Conclusion: This 18F-AV45 PET amyloid imaging study showed no specific regional pattern of cortical 18F-AV45 binding in PCA patients. These results confirm that a distinct clinical phenotype in amnestic AD and PCA is not related to amyloid distribution.

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

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    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.

  2. Correlations between measures of executive attention and cortical thickness of left posterior middle frontal gyrus - a dichotic listening study

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    Lundervold Arvid

    2009-10-01

    Full Text Available Abstract Background The frontal lobe has been associated to a wide range of cognitive control functions and is also vulnerable to degeneration in old age. A recent study by Thomsen and colleagues showed a difference between a young and old sample in grey matter density and activation in the left middle frontal cortex (MFC and performance on a dichotic listening task. The present study investigated this brain behaviour association within a sample of healthy older individuals, and predicted a positive correlation between performance in a condition requiring executive attention and measures of grey matter structure of the posterior left MFC. Methods A dichotic listening forced attention paradigm was used to measure attention control functions. Subjects were instructed to report only the left or the right ear syllable of a dichotically presented consonant-vowel syllable pair. A conflict situation appears when subjects are instructed to report the left ear stimulus, caused by the conflict with the bottom-up, stimulus-driven right ear advantage. Overcoming this processing conflict was used as a measure of executive attention. Thickness and volumes of frontal lobe regions were derived from automated segmentation of 3D magnetic resonance image acquisitions. Results The results revealed a statistically significant positive correlation between the thickness measure of the left posterior MFC and performance on the dichotic listening measures of executive attention. Follow-up analyses showed that this correlation was only statistically significant in the subgroup that showed the typical bottom-up, stimulus-driven right ear advantage. Conclusion The results suggest that the left MFC is a part of an executive attention network, and that the dichotic listening forced attention paradigm may be a feasible tool for assessing subtle attentional dysfunctions in older adults.

  3. The role of the posterior temporal and medial prefrontal cortices in mediating learning from romantic interest and rejection.

    Science.gov (United States)

    Cooper, Jeffrey C; Dunne, Simon; Furey, Teresa; O'Doherty, John P

    2014-09-01

    Romantic interest or rejection can be powerful incentives not merely for their emotional impact, but for their potential to transform, in a single interaction, what we think we know about another person--or ourselves. Little is known, though, about how the brain computes expectations for, and learns from, real-world romantic signals. In a novel "speed-dating" paradigm, we had participants meet potential romantic partners in a series of 5-min "dates," and decide whether they would be interested in seeing each partner again. Afterward, participants were scanned with functional magnetic resonance imaging while they were told, for the first time, whether that partner was interested in them or rejected them. Expressions of interest and rejection activated regions previously associated with "mentalizing," including the posterior superior temporal sulcus (pSTS) and rostromedial prefrontal cortex (RMPFC); while pSTS responded to differences from the participant's own decision, RMPFC responded to prediction errors from a reinforcement-learning model of personal desirability. Responses in affective regions were also highly sensitive to participants' expectations. Far from being inscrutable, then, responses to romantic expressions seem to involve a quantitative learning process, rooted in distinct sources of expectations, and encoded in neural networks that process both affective value and social beliefs.

  4. Clinical and neuroimaging characterization of posterior cortical atrophy%后皮质萎缩临床和影像学特点分析

    Institute of Scientific and Technical Information of China (English)

    石志鸿; 蔡莉; 刘帅; 王颖; 韩彤; 刘淑玲; 周玉颖; 王晓丹; 王新平

    2015-01-01

    目的 探讨后皮质萎缩(PCA)的临床及影像学特点. 方法 对5例PCA患者的临床、神经心理量表及核磁共振、18F-脱氧葡萄糖(FDG)及11C-匹兹堡化合物B(PIB)正电子发射断层(PET)显像进行分析,并与6例早发典型的阿尔茨海默病(AD)进行比较. 结果 PCA患者早期症状主要为视空间障碍、视觉失认、失用、方向感缺失、失写及失算.神经心理量表提示视空间结构、书写、计算力受累突出.PCA组较典型AD组后部皮层萎缩明显(P<0.05),轻度痴呆患者典型AD组较PCA组颞叶内侧萎缩(MTA)明显,但中度痴呆患者均表现为明显萎缩,两组比较差异无统计学意义.FDG PET提示右侧为著的颞顶枕联合区低代谢,额叶受累较轻.PCA组较典型AD组患者枕叶代谢减低,尤其在右枕(BA18,19,37).基于体素水平自动化分析结果显示PCA和典型AD患者PIB平均摄取率(SUVR)在下顶叶、颞叶外侧、额中回、前额内侧皮质、后扣带回和(或)楔前叶、枕叶、辅助运动区和纹状体增高(1.6~2.6,正常对照1.1~1.2,P<0.05).PCA和典型AD患者比较PIB SUVR在所有感兴趣区差异无统计学意义(P>0.05). 结论 PCA以视觉障碍、失用、顶叶皮层萎缩、右侧为著的颞顶枕联合区低代谢为主要特点,皮层淀粉样蛋白沉积与典型早发阿尔茨海默病相似.%Objective To investigate the clinical and image characteristics in patients with posterior cortical atrophy (PCA).Methods Totally 5 patients with PCA and 6 patients with typical Alzheimer's disease (tAD) were selected in this study.Cognitive function was measured by the MiniMental State Examination (MMSE),Montreal Cognitive Assessment (MCA) and Clinical Dementia Rating (CDR).Brain magnetic resonance imaging was conducted to evaluate the ventricular enlargement,and posterior atrophy and medial temporal lobe atrophy.18F Fluorodeoxyglucose (FDG) and 18C-Pittsburg Compound B (PiB) PET cerebral imaging were performed

  5. Cerebral blood flow in posterior cortical nodes of the default mode network decreases with task engagement but remains higher than in most brain regions.

    Science.gov (United States)

    Pfefferbaum, Adolf; Chanraud, Sandra; Pitel, Anne-Lise; Müller-Oehring, Eva; Shankaranarayanan, Ajit; Alsop, David C; Rohlfing, Torsten; Sullivan, Edith V

    2011-01-01

    Functional neuroimaging studies provide converging evidence for existence of intrinsic brain networks activated during resting states and deactivated with selective cognitive demands. Whether task-related deactivation of the default mode network signifies depressed activity relative to the remaining brain or simply lower activity relative to its resting state remains controversial. We employed 3D arterial spin labeling imaging to examine regional cerebral blood flow (CBF) during rest, a spatial working memory task, and a second rest. Change in regional CBF from rest to task showed significant normalized and absolute CBF reductions in posterior cingulate, posterior-inferior precuneus, and medial frontal lobes . A Statistical Parametric Mapping connectivity analysis, with an a priori seed in the posterior cingulate cortex, produced deactivation connectivity patterns consistent with the classic "default mode network" and activation connectivity anatomically consistent with engagement in visuospatial tasks. The large task-related CBF decrease in posterior-inferior precuneus relative to its anterior and middle portions adds evidence for the precuneus' heterogeneity. The posterior cingulate and posterior-inferior precuneus were also regions of the highest CBF at rest and during task performance. The difference in regional CBF between intrinsic (resting) and evoked (task) activity levels may represent functional readiness or reserve vulnerable to diminution by conditions affecting perfusion.

  6. Anetodermia y otras atrofias circunscriptas de la piel Anetoderma and localized atrophies of the skin

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    RE Achenbach

    Full Text Available Efectuamos una revisión de las denominadas atrofias circunscriptas de la piel, con énfasis en la anetodermia y la atrofodermia; ilustramos algunos casos vividos en los últimos años.A review of the localized atrophies of the skin, focusing in the anetodermia and atrophoderma are made. Some of the cases from our Department of Dermatology are pictured.

  7. Atrofia óptica hereditaria. Presentación de tres casos.

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    Esther Díaz Guzmán

    2006-03-01

    Full Text Available Se realizó un estudio descriptivo que incluyó a tres miembros de una familia, comenzando por una paciente, su hijo y un nieto, todos con una atrofia óptica dominante, con daños visuales variables en dependencia del progreso de la enfermedad, y por lo tanto con necesidad de ayudas ópticas o no. Se tomaron fotos del fondo de ojo de cada paciente, y se presentan como un caso de gran interés oftalmológico, seguido incluso por la consulta de genética en nuestra provincia.

  8. Estudo de 43 pacientes com atrofia muscular espinhal e seu diagnóstico molecular

    OpenAIRE

    Carvalho, Laís Regina Rocha de; Scola, Rosana Herminia

    2003-01-01

    Apendice e Anexos Orientadora: Rosana Herminia Scola Dissertaçao(mestrado)- Universidade Federal do Paraná. Setor de Ciencias da Saúde. Departamento de Clínica Médica. Curso de Pós-graduaçao em Medicina Interna Inclui bibliografia Resumo: A atrofia muscular espinhal e uma doenca degenerativa das celulas do como anterior da medula, com quatro tipos descritos (I, II, IIIa/b, IV). Somente os tipos I, II, Illa e Illb apresentam comprometimento do cromossomo 5ql3, em que dois genes sao...

  9. Atrofia muscular espinhal: diagnóstico, tratamento e perspectivas futuras

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    Mariana T. C. Baioni

    2010-08-01

    Full Text Available OBJETIVO: Relatar as recentes descobertas genéticas e moleculares, juntamente com as perspectivas futuras, para o tratamento da atrofia muscular espinhal, auxiliando, dessa forma, os profissionais da área da saúde a fazerem um rápido diagnóstico e proporcionarem um suporte terapêutico correto e precoce. FONTES DOS DADOS: As informações foram coletadas a partir de artigos científicos publicados nas duas últimas décadas, pesquisados nas bases de dados SciELO, PubMed e MEDLINE. SÍNTESE DOS DADOS: A atrofia muscular espinhal é uma doença neurodegenerativa com herança genética autossômica recessiva. É causada por uma deleção homozigótica do gene de sobrevivência do motoneurônio. Essa alteração genética resulta na redução dos níveis da proteína de sobrevivência do motoneurônio, levando à degeneração de motoneurônios alfa da medula espinhal, o que resulta em fraqueza e paralisia muscular proximal progressiva simétrica. Sabe-se que alguns cuidados básicos referentes à nutrição, respiração e fisioterapia podem ser importantes para retardar o progresso da doença e prolongar a vida dos pacientes. Vários medicamentos estão sendo testados, alguns novos, outros já conhecidos, como o ácido valproico, sendo que a paralisia pode ser estacionada, mas não revertida. CONCLUSÕES: A atrofia muscular espinhal é uma desordem de difícil diagnóstico, por ser pouco conhecida, e de tratamento ainda incerto. Os tratamentos farmacológicos e as terapias de suporte existentes ainda não são capazes de recuperar os motoneurônios ou as células musculares que já foram perdidos, mas têm o objetivo de retardar o progresso da doença e melhorar a função muscular residual dos pacientes, bem como oferecer uma melhor qualidade e expectativa de vida.

  10. Metabolic changes in the anterior and posterior cingulate cortices of the normal aging brain: proton magnetic resonance spectroscopy study at 3 T.

    Science.gov (United States)

    Chiu, Pui-Wai; Mak, Henry Ka-Fung; Yau, Kelvin Kai-Wing; Chan, Queenie; Chang, Raymond Chuen-Chung; Chu, Leung-Wing

    2014-02-01

    Magnetic resonance spectroscopy (MRS) can explore aging at a molecular level. In this study, we investigated the relationships between regional concentrations of metabolites (such as choline, creatine, myo-inositol, and N-acetyl-aspartate) and normal aging in 30 cognitively normal subjects (15 women and 15 men, age range 22-82, mean = 49.9 ± 18.3 years) using quantitative proton magnetic resonance spectroscopy. All MR scans were performed using a 3 T scanner. Point resolved spectroscopy was used as the volume selection method for the region-of-interest and the excitation method for water suppression. Single voxel spectroscopy with short echo time of 39 ms and repetition time of 2,000 ms was employed. Single voxels were placed in the limbic regions, i.e., anterior cingulate cortex (ACC), posterior cingulate cortex (PCC), and left and right hippocampi. Cerebrospinal fluid normalization and T1 and T2 correction factors were implemented in the calculation of absolute metabolite concentrations. A standardized T1W 3D volumetric fast field echo and axial T2-weighted fast spin-echo images were also acquired. Our results showed significant positive correlation of choline (r = 0.545, p = 0.002), creatine (r = 0.571, p = 0.001), and N-acetyl-aspartate (r = 0.674, p age. No significant gender effect on metabolite concentrations was found. In aging, increases in choline and creatine might suggest glial proliferation, and an increase in N-acetyl-aspartate might indicate neuronal hypertrophy. Such findings highlight the metabolic changes of ACC and PCC with age, which could be compensatory to an increased energy demand coupled with a lower cerebral blood flow.

  11. Thymic atrophy in cattle poisoned with Solanum glaucophyllum Atrofia do timo em bovinos intoxicados por Solanum glaucophyllum

    Directory of Open Access Journals (Sweden)

    Paula A. Fontana

    2009-03-01

    metabolismo ósseo, o metabolismo de cálcio e também mostra efeitos na imunomodulação. Precursores de timócitos derivados da medula óssea se diferenciam em linfócitos T maduros. A diferenciação da maioria dos linfócitos T é caracterizada pela expressão variável de moléculas de receptores CD4/CD8 e densidade aumentada dos receptores antigênicos de superfície de células T. Alem disso, há mudanças no padrão de glicosilação de glicolipídeos na superfície celular ou de glicoproteínas. Timócitos mostram uma influência de retro alimentação em células tímicas não-linfóides. Foram analisadas modificações induzidas pelo Sg em linfócitos T e células tímicas não-linfóides de bovinos. Novilhas foram divididas em 5 grupos (controle, intoxicadas com Sg durante 15, 30 ou 60 dias, e grupo provavelmente recuperado. As diferentes populações celulares das novilhas experimentais foram caracterizadas com técnicas histoquímicas, imuno-histoquímicas, lectina-histoquímicas e morfométricas. As novilhas intoxicadas com Sg mostraram uma atrofia cortical progressiva que foi caracterizada usando a lectina aglutinina de amendoim (PNA que reconhece timócitos imaturos. Estes animais também aumentaram as células não-linfóides tímicas por unidade de área, detectadas com a técnica de Picrosirius, lectinas WGA e DBA e anticorpos antipancitoqueratina e anti-S-100. A atrofia de timo observada nos animais intoxicados foi semelhante àquela do processo de envelhecimento fisiológico. Após supressão da intoxicação, foi observado um efeito de reversão nestas mudanças. Estes resultados sugerem que a intoxicação por Sg induza a alteração observada no timo diretamente, pela ação de 1,25-dihidroxivitamina D3, ou indiretamente, pela ação da hipercalcemia.

  12. Menopausia, una endocrinopatía: Atrofia Urogenital y Trastornos de la Sexualidad

    Directory of Open Access Journals (Sweden)

    Roberto Vergara Tamara

    1995-08-01

    Full Text Available

    La atrofia urogonital causada por el estímulo deficiente estrogenito se manifiesta principalmente en la vagina, donde la mucosa sufre un adelgazamiento gradual que permite el predominio de células parabasales e intermedias propias del hipoestrogenismo, volviéndolo altamente sensible al trauma y la infección.

    Clínicamente se traduce en disminución de la humedad vaginal, sensación de llenura en el intróito, ruptura fácil de capilares vaginales con aparición de petequias, irritación, prurito y dispareunia.

    A nivel del endometrio se pueden presentar uno de los siguientes cambios: proliferación débil, atrofia senil, hiperplasia quística, hiperplasia adenomatosa, neoplasia omás raramente trastorno secretor; cambios que corresponden clínicamente a intervalos oligomenorreicos interpuestos por episodios hemorrágicos que finalmente terminan en amenorrea definitiva. En casos de sangrados postoriores ameritaría estudios anatomopatológicos de control obtenidos por biopsia o legrado uterino. Otros cambios que se presentan en el útero incluyen la pérdida de tono en sus ligamentos y elementos de sostén así comola disminución del cuello y su secreción.

    A nivel urinario la pérdida del tono uretral cursará con prolapso de la mucosa a través del meato, uretritis ahacteriana recurrente manifestada por poliaquiuria, disuria de ardor e incluso incontinencia urinaria de esfuerzo.

    Los cambios descritos anteriormente, hacen que la sexualidad femenina sea perturbada al presentarse dispareunia, disminuyendo de ritmo sexual y libido de la mujer haciendo su vida de pareja difícil y caótica. Se ha descrito también que la disminución de estrógenos produce ansiedad, depresión, tensión e irritabilidad al no permitir la disociación del triptófano de la albúmina para así formar sustancias tales como la hidroxitriptamina que participa en el mejoramiento del estado de ánimo. Esta etapa será de adaptación difícil y

  13. Dificuldades diagnósticas na atrofia muscular espinhal Spinal muscular atrophy diagnostic difficulties

    Directory of Open Access Journals (Sweden)

    Alexandra Prufer de Q-C. Araújo

    2005-03-01

    Full Text Available OBJETIVO: Descrever o perfil clínico e laboratorial de pacientes com atrofia muscular espinhal (AME com deleção no gene da proteína sobrevivência do neurônio motor (SMN. MÉTODO: Estudo descritivo de uma série de casos confirmados pela presença da deleção no gene SMN. Determinação da freqüência da positividade dos critérios clínicos e laboratoriais revisados. RESULTADOS: Foram incluídos no estudo 22 casos. Em todos havia paresia simétrica, sendo a localização difusa predominante nos casos de início antes de 6 meses (75 %, enquanto nos demais havia predominância de localização proximal e/ou em membros inferiores (67 %. Fasciculações e atrofia foram freqüentes (82 %. Os exames complementares tiveram resultados variáveis, sendo a positividade da eletroneuromiografia (ENMG de 57 % e da biopsia muscular de 58 %. CONCLUSÃO: A presença de deleção no gene SMN pode ajudar a confirmar o diagnóstico de casos indefinidos .OBJECTIVE: To describe the clinical findings of patients with spinal muscular atrophy (SMA with survival motor neuron (SMN gene deletion. METHOD: Descriptive study of SMA cases confirmed with the deletion of the SMN gene. Frequency determination of positive clinical and laboratory revised diagnostic criteria. RESULTS: All of the 22 included patients had symmetrical muscle weakness, which was diffuse in those with onset of symptoms up to 6 months of age (75 %, and either proximal or predominant in lower limbs in the remaining group (67 %. Fasciculations and atrophy were both frequent findings (82 %. Laboratory tests findings were variable, with a positivity of 57 % for electrophysiology and of 58 % for muscle biopsy. CONCLUSION: The presence of a deletion in the SMN gene can help to confirm this diagnosis in unclear presentations.

  14. 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...

  15. [Reversible cortical atrophy secondary to anti-NMDA receptor antibody encephalitis].

    Science.gov (United States)

    Bravo-Oro, Antonio; Acosta-Yebra, Danae; Grimaldo-Zapata, Ilse P; Reyes-Vaca, Guillermo

    2015-05-16

    Introduccion. La encefalitis por anticuerpos antirreceptor de N-metil-D-aspartato (NMDA) inicialmente se describio como un sindrome paraneoplasico asociado a teratoma de ovario, pero cada vez con mas frecuencia se han ido publicando casos en mujeres jovenes y niños como un cuadro encefalopatico autoinmune secundario en el 40-50% de los casos a un proceso viral. Clinicamente, se caracteriza por un cuadro progresivo de manifestaciones psiquiatricas, crisis convulsivas, discinesias y disautonomias. Un hallazgo neurorradiologico poco comunicado es la atrofia cortical reversible, de la cual se desconoce su mecanismo. Caso clinico. Niña que a los 6 años comenzo con crisis convulsivas focales, con electroencefalograma epileptogeno y tomografia de craneo inicial normal. Se inicio tratamiento anticonvulsionante. A las tres semanas aparecieron nuevas crisis convulsivas, manifestaciones psiquiatricas y alteraciones en el ciclo de sueño-vigilia. Ante la sospecha de encefalitis por anticuerpos antirreceptor de NMDA, estos se determinaron en el suero y el liquido cefalorraquideo con resultado positivo. Resonancia magnetica durante el ingreso con atrofia cortical generalizada. Oncologia Pediatrica descarto asociacion a tumores. A los dos años del cuadro, con la paciente libre de crisis convulsivas, una valoracion neuropsicologica mostro la afectacion de funciones ejecutivas y una resonancia magnetica de control evidencio la recuperacion de la atrofia cortical. Conclusion. El mecanismo de la atrofia cortical reversible se desconoce, pero en pacientes con encefalitis por anticuerpos antirreceptor de NMDA podria ser directamente proporcional a la cantidad de anticuerpos circulantes y el tiempo de exposicion a estos en la corteza cerebral. Es muy importante el diagnostico temprano y el inicio de inmunomodulacion.

  16. 3D打印导板辅助腰椎皮质骨螺钉置入的可行性%Feasibility of three-dimensional printing composite template for lumbar posterior cortical bone screw

    Institute of Scientific and Technical Information of China (English)

    李智多; 袁峰; 盛晓磊; 陆海涛; 姜伟; 李威

    2016-01-01

    spinous process composite guide. Al patients received CT scan. After data were processed using Mimics software for three-dimensional model reconstruction, computer-assisted design of optimum trajactory for lumbar vertebral cortical bone screw placement was worked out and made into a dril and screw template, where the surface was created as the inverse of lumbar posterior surface respectively. The dril template and lumbar model were materialized in a rapid prototyping machine. X-ray and CT scan were conducted to identify the screw position and direction, as wel as pedicle cortical rupture. According to Grade grading, success rates and acceptable rates in groups A, B and C were evaluated and compared. RESULTS AND CONCLUSION:(1) Among the three groups (2 specimens), 20 posterior cortical bone screws were implanted, showing a success rate of 70%(14/20) and acceptable rate of 80%(16/20) in the group A;a success rate of 70%(14/20) and acceptable rate of 95%(19/20) in the group B;a success rate of 95%(19/20) and acceptable rate of 100%(20/20) in the group C. (2) The success rate was significantly higher in the group C than in the groups A and B (P<0.05). The acceptable rate was significantly higher in the group C than in the group A (P<0.05). (3) These results verified that the group of vertebral lamina and spinous process composite template has a high matching relation which improves the safety and accuracy. It can theoretical y reduce the risk of nerve and blood vessel injury. Simultaneously, the construction of crista lambdoidalis is not fit for the surface of template, which cannot completely match with the specimen.

  17. Posterior encephalopathy with vasospasm: MRI and angiography

    Energy Technology Data Exchange (ETDEWEB)

    Weidauer, S.; Gaa, J.; Lanfermann, H.; Zanella, F.E. [Institute of Neuroradiology, University of Frankfurt, Schleusenweg 2-16, 60528, Frankfurt (Germany); Sitzer, M.; Hefner, R. [Department of Neurology, University of Frankfurt, Schleusenweg 2-16, 60528, Frankfurt (Germany)

    2003-12-01

    Posterior encephalopathy is characterised by headache, impairment of consciousness, seizures and progressive visual loss. MRI shows bilateral, predominantly posterior, cortical and subcortical lesions with a distribution. Our aim was to analyse the MRI lesion pattern and angiographic findings because the pathophysiology of posterior encephalopathy is incompletely understood. We report three patients with clinical and imaging findings consistent with posterior encephalopathy who underwent serial MRI including diffusion-weighted imaging (DWI) and construction of apparent diffusion coefficient (ADC) maps, and four-vessel digital subtraction angiography (DSA). DWI revealed symmetrical subcortical and cortical parieto-occipital high signal. High and also low ADCs indicated probable vasogenic and cytotoxic oedema. On follow-up there was focal cortical laminar necrosis, while the white-matter lesions resolved almost completely, except in the arterial border zones. DSA revealed diffuse arterial narrowing, slightly more marked in the posterior circulation. These findings suggest that posterior encephalopathy may in some cases be due to diffuse, severe vasospasm affecting especially in the parieto-occipital grey matter, with its higher vulnerability to ischemia. Cerebral vasospasm due to digitoxin intoxication, resulting in posterior encephalopathy, has not yet been described previously. (orig.)

  18. Desproporção congênita de fibras: atrofia de fibras tipo I- relato de 11 casos

    Directory of Open Access Journals (Sweden)

    José Antonio Levy

    1987-06-01

    Full Text Available Os autores relatam 11 casos de desproporção congênita de fibras, comprovados pelos exames clínicos e complementares, em que as retrações fibrotendinosas precoces foram freqüentes, o CPK mostrou-se elevado e, na biópsia muscular, a histoquímica revelou atrofia seletiva das fibras tipo I. Trata-se de distrofia congênita pouco freqüente, de progressão lenta e evolução benigna.

  19. 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

  20. Efeitos do ácido graxo ômega-3 na prevenção da atrofia muscular induzida pela dexametasona

    OpenAIRE

    Alan Fappi

    2013-01-01

    Várias condições podem estar associadas com a atrofia muscular, tais como inatividade, envelhecimento, septicemia, diabetes, câncer e uso de glicocorticoides. Todas estas condições levam a atrofia muscular através de mecanismos que incluem aumento da degradação proteica e/ou redução na síntese proteica, envolvendo pelo menos cinco sistemas: lisossomal, da calpaína, das caspases, metaloproteinases e o sistema ubiquitina-proteasoma (SUP). Glicocorticoides, tais como a dexametasona, acarretam at...

  1. A Rare Hydrocephalus Complication: Cortical Blindness.

    Science.gov (United States)

    Ünal, Emre; Göçmen, Rahşan; Işıkay, Ayşe İlksen; Tekşam, Özlem

    2015-01-01

    Cortical blindness related to bilateral occipital lobe infarction is an extremely rare complication of hydrocephalus. Compression of the posterior cerebral artery, secondary to tentorial herniation, is the cause of occipital infarction. Particularly in children and mentally ill patients, cortical blindness may be missed. Therefore, early diagnosis and treatment of hydrocephalus is important. We present herein a child of ventricular shunt malfunction complicated by cortical blindness.

  2. 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...

  3. [Cortical blindness].

    Science.gov (United States)

    Chokron, S

    2014-02-01

    Cortical blindness refers to a visual loss induced by a bilateral occipital lesion. The very strong cooperation between psychophysics, cognitive psychology, neurophysiology and neuropsychology these latter twenty years as well as recent progress in cerebral imagery have led to a better understanding of neurovisual deficits, such as cortical blindness. It thus becomes possible now to propose an earlier diagnosis of cortical blindness as well as new perspectives for rehabilitation in children as well as in adults. On the other hand, studying complex neurovisual deficits, such as cortical blindness is a way to infer normal functioning of the visual system.

  4. Posterior Tibial Tendon Dysfunction

    Science.gov (United States)

    .org Posterior Tibial Tendon Dysfunction Page ( 1 ) Posterior tibial tendon dysfunction is one of the most common problems of the foot and ankle. It occurs when the posterior tibial tendon becomes inflamed or torn. As a result, the ...

  5. 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

    Directory of Open Access Journals (Sweden)

    Vishnu S.

    2014-11-01

    Full Text Available 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 0.2 mL of Trypan blue 0.03%(Group B or 0.2mL of balanced salt solution(Group C injected subcapsularly at 2 sites 180 degrees apart after cortical-cleaving hydro dissection. 6 month and 12 month postoperative PCO was analyzed by a masked examiner using the ‘Evaluation of Posterior capsule Opacification (EPCO’ score using the EPCO-2000 software on digitalised images of slitlamp retroillumination. Best corrected visual acuity (BCVA on Snellen’s charts and Nd-YAG capsulotomy rates were also recorded. RESULTS: The difference in mean EPCO score between Group A and Group C was statistically significant both at 6 months (p=0.038 and even at 12 months (p=0.032 using the independent-t-test. The difference in Nd-YAG capsulotomy rates between Group A and Group C was statistically significant both at 6 months (p=0.018 and even at 12 months (p=0.014 using the chi-square test. BCVA ranged from 6/6 to 6/12P Snellen depending on the age-related changes in the cornea and retina. CONCLUSION: 0.06% Trypan blue dye reduced the incidence of posterior capsular opacification (PCO at 6 month and 12 month follow-up as compared to 0.03% trypan blue dye or balanced salt solution in similar manner

  6. Cyclosporine-related reversible posterior leukoencephalopathy: MRI

    Energy Technology Data Exchange (ETDEWEB)

    Jarosz, J.M. [Dept. of Neuroimaging, King`s College Hospital, Denmark Hill, London SE5 (United Kingdom)]|[Magnetic Resonance Centre, U.M.D.S. and Guy`s and St. Thomas` Hospitals N.H.S. Trust, St. Thomas Street, London SE1 9RT (United Kingdom); Howlett, D.C.; Cox, T.C.S.; Bingham, J.B. [Magnetic Resonance Centre, U.M.D.S. and Guy`s and St. Thomas` Hospitals N.H.S. Trust, St. Thomas Street, London SE1 9RT (United Kingdom)

    1997-10-01

    Three patients aged 48, 11 and 40 years, two of whom were recent recipients of renal transplants and one of a bone marrow transplant, developed seizures, with cortical blindness in two cases. All were immunosuppressed with cyclosporine and were hypertensive at the onset of symptoms. MRI showed predominantly posterior signal changes in all three cases. The abnormalities were more conspicuous on fast FLAIR images than on conventional T2-weighted spin-echo images. (orig.). With 4 figs.

  7. Contrast-induced transient cortical blindness.

    Science.gov (United States)

    Shah, Parth R; Yohendran, Jayshan; Parker, Geoffrey D; McCluskey, Peter J

    2013-05-01

    We present a case of transient cortical blindness secondary to contrast medium toxicity. A 58-year-old man had successful endovascular coiling of a right posterior inferior cerebellar artery aneurysm but became confused and unable to see after the procedure. His visual acuity was no light perception bilaterally. Clinically, there was no new intra-ocular pathology. An urgent non-contrast computed tomography scan of the brain showed cortical hyperdensity in both parieto-occipital cortices, consistent with contrast medium leakage through the blood-brain barrier from the coiling procedure. The man remained completely blind for 72 hours, after which his visual acuity improved gradually back to his baseline level.

  8. Escleritis posterior bilateral Bilateral posterior scleritis

    Directory of Open Access Journals (Sweden)

    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.

  9. 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...

  10. Irmandade afetada pela atrofia muscular peroneal de Charcot-Marie-Tooth com possível variante do fenômeno da antecipação

    Directory of Open Access Journals (Sweden)

    Aguinaldo Gonçalves

    1977-06-01

    Full Text Available Considerando-se a peculiaridade genética da atrofia peroneal de Charcot-Marie-Tooth, é feita a descrição clínica de família com três irmãos afetados, com idade de aparecimento progressivamente antecipada, refletindo possível variante do fenômeno da antecipação, condição inusitada na literatura, não só para esta doença, mas também, de modo geral, em Genética Humana.

  11. Avaliação da dor em doentes com atrofia de sistemas múltiplos : estudo comparativo com a doença de Parkinson

    OpenAIRE

    Pinheiro, Sara Figueira da Câmara Lomelino

    2016-01-01

    Trabalho final de mestrado integrado em Medicina área cientifica de Neurologia, apresentado á Faculdade de Medicina da Universidade de Coimbra Introdução: A dor é um sintoma comum nos distúrbios Parkinsónicos, típicos e atípicos, influenciando negativamente a qualidade de vida destes doentes. Objectivo: Analisar a prevalência e as características da dor em doentes com Atrofia de Sistemas Múltiplos, comparando os resultados obtidos com a Doença de Parkinson. Métodos: Inclusão de 20 do...

  12. Congenital contractural arachnodactyly with neurogenic muscular atrophy: case report Aracnodactilia contratural congênita com atrofia muscular espinhal: relato de caso

    Directory of Open Access Journals (Sweden)

    Rosana Herminia Scola

    2001-06-01

    Full Text Available We report the case of a 3-1/2-year-old girl with hypotonia, multiple joint contractures, hip luxation, arachnodactyly, adducted thumbs, dolichostenomelia, and abnormal external ears suggesting the diagnosis of congenital contractural arachnodactyly (CCA. The serum muscle enzimes were normal and the needle electromyography showed active and chronic denervation. The muscle biopsy demonstrated active and chronic denervation compatible with spinal muscular atrophy. Analysis of exons 7 and 8 of survival motor neuron gene through polymerase chain reaction did not show deletions. Neurogenic muscular atrophy is a new abnormality associated with CCA, suggesting that CCA is clinically heterogeneous.Relatamos o caso de uma paciente do sexo feminino de 3 anos e 6 meses com hipotonia, contraturas de múltiplas articulações, aracnodactilia, polegares aduzidos, dolicostenomelia e orelhas externas anormais sugerindo o diagnóstico de aracnodactilia contratural congênita (ACC. As enzimas musculares eram normais e a eletromiografia de agulha mostrou desinervação ativa e crônica. A biópsia muscular mostrou desinervação ativa e crônica compatível com atrofia muscular espinhal. A análise dos exons 7 e 8 do gene do survival motor neuron por reação em cadeia de polimerase não mostrou deleções. Atrofia muscular neurogênica é uma nova anormalidade associada a ACC, sugerindo a heterogeneidade clínica da ACC.

  13. Cortical Visual Impairment

    Science.gov (United States)

    ... Frequently Asked Questions Español Condiciones Chinese Conditions Cortical Visual Impairment En Español Read in Chinese What is cortical visual impairment? Cortical visual impairment (CVI) is a decreased ...

  14. Central cortical cleanup and zonular deficiency

    Science.gov (United States)

    Mansour, Ahmad M; Antonios, Rafic S; Ahmed, Iqbal Ike K

    2016-01-01

    Background Complete removal of the cortex has been advocated to prevent posterior capsular opacification but carries the risk of zonular dehiscence, hence there is a need for a safe maximal cortical cleanup technique in eyes with severe diffuse zonulopathy in subjects above age 90. Methods We used bimanual central cortical cleaning by elevating central fibers and aspirating them toward the periphery. Peripheral cortical fibers were removed passively only when they became loose due to copious irrigation. A one-piece foldable implant was inserted without a capsular tension ring. Postoperative corticosteroid drops were used. Results This technique was safely performed in a dozen eyes with severe pseudo-exfoliation or brunescent cataract with weak zonules. Posterior capsular rupture, iritis, vitreous loss, and lens subluxation were not observed. Moderate capsular phimosis occurred but with maintained central vision. Conclusion The dogma of “complete cortical cleanup” in severe zonulopathy needs to be revisited in favor of a clear visual axis with maximal preservation of the damaged zonules. This technique is ideal in patients above age 90 where posterior capsular opacification and late dislocation of intraocular lens–capsule bag complex are unlikely to occur until several years postoperatively. PMID:27784979

  15. Central cortical cleanup and zonular deficiency

    Directory of Open Access Journals (Sweden)

    Mansour AM

    2016-10-01

    Full Text Available Ahmad M Mansour,1,2 Rafic S Antonios,1 Iqbal Ike K Ahmed3 1Department of Ophthalmology, American University of Beirut, Beirut, Lebanon; 2Department of Ophthalmology, Rafic Hariri University Hospital, Beirut, Lebanon; 3Department of Ophthalmology, University of Toronto, Toronto, ON, Canada Background: Complete removal of the cortex has been advocated to prevent posterior capsular opacification but carries the risk of zonular dehiscence, hence there is a need for a safe maximal cortical cleanup technique in eyes with severe diffuse zonulopathy in subjects above age 90. Methods: We used bimanual central cortical cleaning by elevating central fibers and aspirating them toward the periphery. Peripheral cortical fibers were removed passively only when they became loose due to copious irrigation. A one-piece foldable implant was inserted without a capsular tension ring. Postoperative corticosteroid drops were used. Results: This technique was safely performed in a dozen eyes with severe pseudo-exfoliation or brunescent cataract with weak zonules. Posterior capsular rupture, iritis, vitreous loss, and lens subluxation were not observed. Moderate capsular phimosis occurred but with maintained central vision. Conclusion: The dogma of “complete cortical cleanup” in severe zonulopathy needs to be revisited in favor of a clear visual axis with maximal preservation of the damaged zonules. This technique is ideal in patients above age 90 where posterior capsular opacification and late dislocation of intraocular lens–capsule bag complex are unlikely to occur until several years postoperatively. Keywords: brunescent cataract, cortex aspiration, phacoemulsification, pseudo-exfoliation, weak zonules

  16. Microsurgical anatomy of the posterior circulation

    Directory of Open Access Journals (Sweden)

    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

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

    Directory of Open Access Journals (Sweden)

    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

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

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    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.

  19. Cholelithiasis with atrophy of the right lateral hepatic lobe in a horse Colelitíase com atrofia do lobo lateral direito em um cavalo

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    Renato de Lima Santos

    2007-04-01

    Full Text Available A 22 year-old horse developed cholelithiasis with marked atrophy of the right lateral hepatic lobe. The horse had a history of intermittent colic since three years of age, and one of the first episodes of colic was associated with icterus. The size of the right lateral hepatic lobe was extremely reduced. There was a large choledocholith in the common hepatic duct, and several hepatoliths and choleliths in the intra- and extra-hepatic billiary ducts. Microscopically, there was severe atrophy of the right lobe with diffuse proliferation of connective tissue and billiary ducts. The left lateral lobe had peri-portal fibrosis with proliferation of billiary ducts, and billiary stasis. Chemical analysis of the calculi detected amorphous and triple phosphate, bilirubin, calcium, and iron.Um cavalo de 22 anos de idade desenvolveu quadro de colelitíase severa com atrofia do lobo lateral direito. O animal tinha histórico de cólica recorrente, desde os três anos de idade, sendo que um dos primeiros episódios de cólica foi acompanhado de icterícia. O lobo hepático lateral direito estava extremamente diminuído de volume. Havia um grande coledocólito localizado no ducto hepático comum e inúmeros hepatólitos e colélitos nos ductos biliares intra e extra-hepáticos. Microscopicamente, foi observada atrofia acentuada do lobo direito, com proliferação difusa de tecido conjuntivo fibroso e de ductos biliares. O lobo lateral esquerdo apresentava fibrose periportal difusa associada à proliferação acentuada de ductos biliares e estase biliar. Análise química das concreções detectou fosfato triplo e amorfo, bilirrubina, cálcio e ferro.

  20. 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...... that 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...... midtemporal cortex exclusively during jingle thinking. The intermediate and remote visual association areas, the superior occipital, posterior inferior temporal, and posterior superior parietal cortex, increased their rCBF exclusively during route-finding thinking. We observed no decreases in rCBF. All r...

  1. Cortical Polarity of the RING Protein PAR-2 Is Maintained by Exchange Rate Kinetics at the Cortical-Cytoplasmic Boundary.

    Science.gov (United States)

    Arata, Yukinobu; Hiroshima, Michio; Pack, Chan-Gi; Ramanujam, Ravikrishna; Motegi, Fumio; Nakazato, Kenichi; Shindo, Yuki; Wiseman, Paul W; Sawa, Hitoshi; Kobayashi, Tetsuya J; Brandão, Hugo B; Shibata, Tatsuo; Sako, Yasushi

    2016-08-23

    Cell polarity arises through the spatial segregation of polarity regulators. PAR proteins are polarity regulators that localize asymmetrically to two opposing cortical domains. However, it is unclear how the spatially segregated PAR proteins interact to maintain their mutually exclusive partitioning. Here, single-molecule detection analysis in Caenorhabditis elegans embryos reveals that cortical PAR-2 diffuses only short distances, and, as a result, most PAR-2 molecules associate and dissociate from the cortex without crossing into the opposing domain. Our results show that cortical PAR-2 asymmetry is maintained by the local exchange reactions that occur at the cortical-cytoplasmic boundary. Additionally, we demonstrate that local exchange reactions are sufficient to maintain cortical asymmetry in a parameter-free mathematical model. These findings suggest that anterior and posterior PAR proteins primarily interact through the cytoplasmic pool and not via cortical diffusion.

  2. Cortical Polarity of the RING Protein PAR-2 Is Maintained by Exchange Rate Kinetics at the Cortical-Cytoplasmic Boundary

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    Yukinobu Arata

    2016-08-01

    Full Text Available Cell polarity arises through the spatial segregation of polarity regulators. PAR proteins are polarity regulators that localize asymmetrically to two opposing cortical domains. However, it is unclear how the spatially segregated PAR proteins interact to maintain their mutually exclusive partitioning. Here, single-molecule detection analysis in Caenorhabditis elegans embryos reveals that cortical PAR-2 diffuses only short distances, and, as a result, most PAR-2 molecules associate and dissociate from the cortex without crossing into the opposing domain. Our results show that cortical PAR-2 asymmetry is maintained by the local exchange reactions that occur at the cortical-cytoplasmic boundary. Additionally, we demonstrate that local exchange reactions are sufficient to maintain cortical asymmetry in a parameter-free mathematical model. These findings suggest that anterior and posterior PAR proteins primarily interact through the cytoplasmic pool and not via cortical diffusion.

  3. [Parietal Cortices and Body Information].

    Science.gov (United States)

    Naito, Eiichi; Amemiya, Kaoru; Morita, Tomoyo

    2016-11-01

    Proprioceptive signals originating from skeletal muscles and joints contribute to the formation of both the human body schema and the body image. In this chapter, we introduce various types of bodily illusions that are elicited by proprioceptive inputs, and we discuss distinct functions implemented by different parietal cortices. First, we illustrate the primary importance of the motor network in the processing of proprioceptive (kinesthetic) signals originating from muscle spindles. Next, we argue that the right inferior parietal cortex, in concert with the inferior frontal cortex (both regions connected by the inferior branch of the superior longitudinal fasciculus-SLF III), may be involved in the conscious experience of body image. Further, we hypothesize other functions of distinct parietal regions: the association between internal hand motor representation with external object representation in the left inferior parietal cortex, visuo-kinesthetic processing in the bilateral posterior parietal cortices, and the integration of somatic signals from different body parts in the higher-order somatosensory parietal cortices. Our results indicate that a distinct parietal region, in concert with its anatomically and functionally connected frontal regions, probably plays specialized roles in the processing of body-related information.

  4. Assessment of cortical maturation with prenatal MRI. Part I: normal cortical maturation

    Energy Technology Data Exchange (ETDEWEB)

    Fogliarini, Celine [Faculte Timone, Centre de Resonance Magnetique Biologique et Medicale, Marseille (France); Chaumoitre, Katia [Hopital Nord, Department of Radiology, Marseille (France); Chapon, Frederique; Levrier, Olivier; Girard, Nadine [Hopital Timone, Department of Neuroradiology, Marseille Cedex 5 (France); Fernandez, Carla; Figarella-Branger, Dominique [Hopital Timone, Department of Pathology, Marseille (France)

    2005-08-01

    Cortical maturation, especially gyral formation, follows a temporospatial schedule and is a good marker of fetal maturation. Although ultrasonography is still the imaging method of choice to evaluate fetal anatomy, MRI has an increasingly important role in the detection of brain abnormalities, especially of cortical development. Knowledge of MRI techniques in utero with the advantages and disadvantages of some sequences is necessary, in order to try to optimize the different magnetic resonance sequences to be able to make an early diagnosis. The different steps of cortical maturation known from histology represent the background necessary for the understanding of maturation in order to be then able to evaluate brain maturation through neuroimaging. Illustrations of the normal cortical maturation are given for each step accessible to MRI for both the cerebral hemispheres and the posterior fossa. (orig.)

  5. Spondylolisthesis and Posterior Instability

    Energy Technology Data Exchange (ETDEWEB)

    Niggemann, P.; Beyer, H.K.; Frey, H.; Grosskurth, D. (Privatpraxis fuer Upright MRT, Koeln (Germany)); Simons, P.; Kuchta, J. (Media Park Klinik, Koeln (Germany))

    2009-04-15

    We present the case of a patient with a spondylolisthesis of L5 on S1 due to spondylolysis at the level L5/S1. The vertebral slip was fixed and no anterior instability was found. Using functional magnetic resonance imaging (MRI) in an upright MRI scanner, posterior instability at the level of the spondylolytic defect of L5 was demonstrated. A structure, probably the hypertrophic ligament flava, arising from the spondylolytic defect was displaced toward the L5 nerve root, and a bilateral contact of the displaced structure with the L5 nerve root was shown in extension of the spine. To our knowledge, this is the first case described of posterior instability in patients with spondylolisthesis. The clinical implications of posterior instability are unknown; however, it is thought that this disorder is common and that it can only be diagnosed using upright MRI.

  6. Posterior tracheal diverticulosis.

    Science.gov (United States)

    Madan, Karan; Das, Chandan J; Guleria, Randeep

    2014-10-01

    Multiple tracheal diverticulosis is a rare clinical entity. Tracheal diverticula are usually recognized radiologically as solitary right paratracheal air collections on thoracic computed tomography examination. They are usually asymptomatic but can occasionally present with persistent symptoms. We herein report the case of a 50-year-old male patient who underwent extensive evaluation for persistent cough. Multiple posterior right paratracheal air collections were recognized on thoracic multidetector computed tomography examination, which was confirmed as multiple-acquired posterior upper tracheal diverticula on flexible bronchoscopy. The patient improved with conservative medical management.

  7. Age Effects on Cortical Thickness in Cognitively Normal Elderly Individuals

    Directory of Open Access Journals (Sweden)

    Sona Hurtz

    2014-07-01

    Full Text Available Background/Aims: Atrophy in both grey and white matter is found in normal aging. The prefrontal cortex and the frontal lobe white matter are thought to be the most affected regions. Our aim was to examine the effects of normal aging on cortical grey matter using a 3D quantitative cortical mapping method. Methods: We analyzed 1.5-tesla brain magnetic resonance imaging data from 44 cognitively normal elderly subjects using cortical pattern matching and cortical thickness analyses. Linear regression analysis was used to study the effect of age on cortical thickness. 3D map-wide correction for multiple comparisons was conducted with permutation analyses using a threshold of p Results: We found a significant negative association between age and cortical thickness in the right hemisphere (pcorrected = 0.009 and a trend level association in the left hemisphere (pcorrected = 0.081. Age-related changes were greatest in the sensorimotor, bilateral dorsal anterior cingulate and supplementary motor cortices, and the right posterior middle and inferior frontal gyri. Age effects greater in the medial than lateral visual association cortices were also seen bilaterally. Conclusion: Our novel method further validates that normal aging results in diffuse cortical thinning that is most pronounced in the frontal and visual association cortices.

  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. Posterior Urethral Valves

    Directory of Open Access Journals (Sweden)

    Steve J. Hodges

    2009-01-01

    Full Text Available The most common cause of lower urinary tract obstruction in male infants is posterior urethral valves. Although the incidence has remained stable, the neonatal mortality for this disorder has improved due to early diagnosis and intensive neonatal care, thanks in part to the widespread use of prenatal ultrasound evaluations. In fact, the most common reason for the diagnosis of posterior urethral valves presently is the evaluation of infants for prenatal hydronephrosis. Since these children are often diagnosed early, the urethral obstruction can be alleviated rapidly through catheter insertion and eventual surgery, and their metabolic derangements can be normalized without delay, avoiding preventable infant mortality. Of the children that survive, however, early diagnosis has not had much effect on their long-term prognosis, as 30% still develop renal insufficiency before adolescence. A better understanding of the exact cause of the congenital obstruction of the male posterior urethra, prevention of postnatal bladder and renal injury, and the development of safe methods to treat urethral obstruction prenatally (and thereby avoiding the bladder and renal damage due to obstructive uropathy are the goals for the care of children with posterior urethral valves[1].

  10. Heterogeneidade genética em atrofia óptica autossômica dominante Genetic heterogeneity in autosomal dominant optic atrophy

    Directory of Open Access Journals (Sweden)

    Juliana Maria Ferraz Sallum

    2002-08-01

    Full Text Available Objetivos: A atrofia óptica autossômica dominante, tipo Kjer ou juvenil, é neuropatia óptica hereditária que causa perda de acuidade visual, anormalidades da visão de cores e defeitos do campo visual, caracterizada por palidez do disco óptico. O gene desta doença foi mapeado por análise de ligação genética em um intervalo de 1,4 cM no cromossomo 3q28-29 entre os marcadores microssatélites D3S3669 e D3S3562. Embora a maioria das famílias estudadas tenha mostrado ligação para a região cromossômica 3q28-29, uma família foi mapeada no cromossomo 18q12.2-12.3. Este trabalho analisa a ligação da atrofia óptica em três famílias com marcadores polimórficos para os cromossomos 3q28-29 e 18q12.2-12.3. Métodos: Cinqüenta e sete indivíduos de três famílias foram submetidos a exame oftalmológico e coleta de sangue. O DNA foi extraído e amplificado em reações de polimerase em cadeia (PCR com marcadores polimórficos para os cromossomos 3q28-29 e 18q12.2-12.3. Os fragmentos de PCR foram mensurados em seqüenciador automático (373 DNA sequencer. Estes números foram utilizados como alelos para análise de haplótipos. Os "lod scores" foram calculados pelo programa MLINK. Resultados: Na primeira família houve suspeita da atrofia óptica mapear para o cromossomo 3q28-29, mas sem significância estatística no valor do "lod score". Na segunda família a atrofia óptica apresentou ligação para este locus. Os eventos de recombinação nesta família localizaram o gene num intervalo de 2 cM entre os marcadores D3S3669 e D3S2305. O "lod score" máximo obtido foi de 3,56 no theta de 0,00 com o marcador D3S3669. A terceira família não apresentou ligação nos cromossomos 3q28-29 e 18q12.2-12.3. Conclusão: O fato da terceira família não mapear para nenhum dos dois loci já descritos é indicativo de que existe heterogeneidade genética na atrofia óptica autossômica dominante e levanta a possibilidade de existir um terceiro

  11. 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.

  12. 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

  13. Buccal cortical bone thickness on CBCT for mini-implant

    Energy Technology Data Exchange (ETDEWEB)

    Goo, Jong Gook; Lim, Sung Hoon; Lee, Byoung Jin; Kim, Jae Duk [School of Dentistry, Chosun University, Gwangju (Korea, Republic of)

    2010-12-15

    Cortical bone thickness is one of the important factor in mini-implant stability. This study was performed to investigate the buccal cortical bone thickness at every interdental area as an aid in planning mini-implant placement. Two-dimensional slices at every interdental area were selected from the cone-beam computed tomography scans of 20 patients in third decade. Buccal cortical bone thickness was measured at 2, 4, and 6 mm levels from the alveolar crest in the interdental bones of posterior regions of both jaws using the plot profile function of Ez3D2009TM (Vatech, Yongin, Korea). The results were analyzed using by Mann-Whitney test. Buccal cortical bone was thicker in the mandible than in the maxilla. The thickness increased with further distance from the alveolar crest in the maxilla and with coming from the posterior to anterior region in the mandible (p?0.01). The maximum CT value showed an increasing tendency with further distance from the alveolar crest and with coming from posterior to anterior region in both jaws. Interdental buccal cortical bone thickness varied in both jaws, however our study showed a distinct tendency. We expect that these results could be helpful for the selection and preparation of mini-implant sites.

  14. Preparative activities in posterior parietal cortex for self-paced movement in monkeys.

    Science.gov (United States)

    Gemba, Hisae; Matsuura-Nakao, Kazuko; Matsuzaki, Ryuichi

    2004-02-26

    Cortical field potentials were recorded by electrodes implanted chronically on the surface and at a 2.0-3.0 mm depth in various cortices in monkeys performing self-paced finger, toe, mouth, hand or trunk movements. Surface-negative, depth-positive potentials (readiness potential) appeared in the posterior parietal cortex about 1.0 s before onset of every self-paced movement, as well as in the premotor, motor and somatosensory cortices. Somatotopical distribution was seen in the readiness potential in the posterior parietal cortex, although it was not so distinct as that in the motor or somatosensory cortex. This suggests that the posterior parietal cortex is involved in preparation for self-paced movement of any body part. This study contributes to the investigation of central nervous mechanisms of voluntary movements initiated by internal stimulus.

  15. Cortical Blindness in a Child Secondary to Mycoplasma pneumoniae Infection.

    Science.gov (United States)

    Garcia Tirado, A; Jimenez-Rolando, B; Noval, S; Martinez Bermejo, A

    2017-01-01

    Our objective is to present a case of an uncommon complication associated with Mycoplasma pneumoniae infection in a child where cortical blindness was the main clinical feature. Stroke due to an infection by M. pneumoniae is very uncommon. No consensus has been reached on the pathogenesis, although several pathogenic mechanisms have been proposed. Occlusion of posterior cerebral circulation is the most uncommon central nervous system complication of M. pneumoniae infection being reported. Symptoms are usually hemiplegia and dysarthria. We report a case of a 6-year-old boy who suffered cortical blindness due to a stroke 2 days after M. pneumoniae infection. This is the first case of documented cortical blindness due to posterior cerebral arteries occlusion in children after M. pneumoniae infection.

  16. Posterior reversible encephalopathy syndrome is not associated with mutations in aquaporin-4.

    Science.gov (United States)

    Matiello, Marcelo; Muralidharan, Rajanandini; Sun, David; Rabinstein, Alejandro A; Weinshenker, Brian G

    2015-08-01

    Posterior reversible encephalopathy syndrome (PRES) is characterized by acute reversible subcortical vasogenic edema that is typically bilateral and self-limiting. It preferentially affects posterior regions of the brain. Clinical manifestations include encephalopathy, seizures, headache, and cortical blindness. PRES may be precipitated by hypertensive crises such as eclampsia and by immunosuppressive agents. The pathophysiology of PRES is incompletely understood. Disordered cerebral autoregulation leading to protein and fluid extravasation is thought to be important.(1) Other theories implicate endothelial dysfunction or vasospasm.(2).

  17. 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.

  18. Permanent cortical blindness after bronchial artery embolization.

    Science.gov (United States)

    van Doorn, Colette S; De Boo, Diederick W; Weersink, Els J M; van Delden, Otto M; Reekers, Jim A; van Lienden, Krijn P

    2013-12-01

    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.

  19. Cortical visual impairment: Characteristics and treatment

    OpenAIRE

    Vučinić, Vesna; Anđelković, Marija; Jablan, Branka; Žigić, Vesna

    2014-01-01

    According to the latest studies, Cortical visual impairment – CVI is one of the most common causes of problems and difficulties in visual functioning. It results from the impairment of the central part of visual system, i.e. visual cortex, posterior visual pathway, or both. The diagnosis is usually made in the first three years of life. The aim of this paper is to present the characteristics of children with CVI, and the strategies used for treatment. CVI has a negative impact on almost all d...

  20. The Simplified Posterior Interosseous Flap.

    Science.gov (United States)

    Cavadas, Pedro C; Thione, Alessandro; Rubí, Carlos

    2016-09-01

    Several technical modifications have been described to avoid complications and simplify dissection. The authors describe some technical tips that make posterior interosseous flap dissection safer and more straightforward.

  1. Selective and superselective angiography of pediatric moyamoya disease angioarchitecture in the posterior circulation.

    Science.gov (United States)

    Baltsavias, Gerasimos; Khan, Nadia; Filipce, Venko; Valavanis, Anton

    2014-01-01

    The anastomotic network of the posterior circulation in children with moyamoya disease has not been analyzed. We aimed to investigate the angiographic anatomy of this unique vascular network in patients with childhood moyamoya disease. Selective and superselective injections of the posterior circulation were performed in six children with newly diagnosed moyamoya disease. The arterial branches feeding the moyamoya anastomotic network, their connections and the recipient vessels were demonstrated. Depending on the level of the steno-occlusive lesion, the feeding vessels were the thalamoperforators, the posterior choroidals, the splenic artery, parietoccipital artery, other cortical posterior cerebral artery (PCA) branches, the dural branch of the PCA, the premamillary artery and other posterior communicating artery perforators. Through connections, which are described, the recipient vessels were the striate and medullary arteries, other thalamic arteries with or without medullary extensions, the pericallosal artery, medial parietoccipital cortical branches of the PCA and the anterior choroidal artery. High quality selective and superselective angiography helped in demonstrating the angiographic anatomy of the moyamoya posterior anastomotic network previously either vaguely or incompletely described, as well as connections within the posterior circulation but also its relevance as a collateral to the anterior circulation.

  2. Evolution of cortical neurogenesis.

    Science.gov (United States)

    Abdel-Mannan, Omar; Cheung, Amanda F P; Molnár, Zoltán

    2008-03-18

    The neurons of the mammalian neocortex are organised into six layers. By contrast, the reptilian and avian dorsal cortices only have three layers which are thought to be equivalent to layers I, V and VI of mammals. Increased repertoire of mammalian higher cognitive functions is likely a result of an expanded cortical surface area. The majority of cortical cell proliferation in mammals occurs in the ventricular zone (VZ) and subventricular zone (SVZ), with a small number of scattered divisions outside the germinal zone. Comparative developmental studies suggest that the appearance of SVZ coincides with the laminar expansion of the cortex to six layers, as well as the tangential expansion of the cortical sheet seen within mammals. In spite of great variation and further compartmentalisation in the mitotic compartments, the number of neurons in an arbitrary cortical column appears to be remarkably constant within mammals. The current challenge is to understand how the emergence and elaboration of the SVZ has contributed to increased cortical cell diversity, tangential expansion and gyrus formation of the mammalian neocortex. This review discusses neurogenic processes that are believed to underlie these major changes in cortical dimensions in vertebrates.

  3. 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…

  4. Cortical Lewy Body Dementia

    Directory of Open Access Journals (Sweden)

    W. R. G. Gibb

    1990-01-01

    Full Text Available In cortical Lewy body dementia the distribution of Lewy bodies in the nervous system follows that of Parkinson's disease, except for their greater profusion in the cerebral cortex. The cortical tangles and plaques of Alzheimer pathology are often present, the likely explanation being that Alzheimer pathology provokes dementia in many patients. Pure cortical Lewy body dementia without Alzheimer pathology is uncommon. The age of onset reflects that of Parkinson's disease, and clinical features, though not diagnostic, include aphasias, apraxias, agnosias, paranoid delusions and visual hallucinations. Parkinsonism may present before or after the dementia, and survival duration is approximately half that seen in Parkinson's disease without dementia.

  5. Análise bioquímica das metaloproteases da matriz extracelular durante atrofia experimental das glândulas salivares submandibulares em ratos Analysis of the matrix metalloproteases in duct-ligated submandibular salivary glands of rats

    OpenAIRE

    Souza, Ana Paula de [UNESP; TREVILATTO, Paula Cristina; ZAIA, Alexandre Augusto; LINE, Sérgio Roberto Peres

    1999-01-01

    O presente estudo teve por objetivo analisar a expressão das metaloproteases da matriz extracelular durante a atrofia experimental das glândulas submandibulares em ratos, causada pela obstrução do ducto excretor principal. Os zimogramas realizados com extratos das porções internas e externas das glândulas salivares normais e ligadas mostraram que as principais enzimas gelatinolíticas possuíam pesos moleculares variando entre 72 kDa e 65 kDa. A atividade dessas enzimas aumentou progressivament...

  6. Postpartum cortical blindness.

    Science.gov (United States)

    Faiz, Shakeel Ahmed

    2008-09-01

    A 30-years-old third gravida with previous normal pregnancies and an unremarkable prenatal course had an emergency lower segment caesarean section at a periphery hospital for failure of labour to progress. She developed bilateral cortical blindness immediately after recovery from anesthesia due to cerebral angiopathy shown by CT and MR scan as cortical infarct cerebral angiopathy, which is a rare complication of a normal pregnancy.

  7. Classification of posterior vitreous detachment

    Directory of Open Access Journals (Sweden)

    Kakehashi A

    2013-12-01

    Full Text Available Akihiro Kakehashi,1 Mikiko Takezawa,1 Jun Akiba21Department of Ophthalmology, Jichi Medical University, Saitama Medical Center, Saitama, 2Kanjodori Eye Clinic, Asahikawa, JapanAbstract: Diagnosing a posterior vitreous detachment (PVD is important for predicting the prognosis and determining the indication for vitreoretinal surgery in many vitreoretinal diseases. This article presents both classifications of a PVD by slit-lamp biomicroscopy and of a shallow PVD by optical coherence tomography (OCT. By biomicroscopy, the vitreous condition is determined based on the presence or absence of a PVD. The PVD then is classified as either a complete posterior vitreous detachment (C-PVD or a partial posterior vitreous detachment (P-PVD. A C-PVD is further divided into a C-PVD with collapse and a C-PVD without collapse, while a P-PVD is divided into a P-PVD with shrinkage of the posterior hyaloid membrane (P-PVD with shrinkage and a P-PVD without shrinkage of the posterior hyaloid membrane (P-PVD without shrinkage. A P-PVD without shrinkage has a subtype characterized by vitreous gel attachment through the premacular hole in a posterior hyaloid membrane to the macula (P-PVD without shrinkage [M]. By OCT, a shallow PVD is classified as the absence of a shallow PVD or as a shallow PVD. A shallow PVD is then subclassified as a shallow PVD without shrinkage of the posterior vitreous cortex, a shallow PVD with shrinkage of the posterior vitreous cortex, and a peripheral shallow PVD. A shallow PVD without shrinkage of the posterior vitreous cortex has two subtypes: an age-related shallow PVD and a perifoveal PVD associated with a macular hole.Keywords: classification, optical coherence tomography, PVD, slit-lamp biomicroscopy

  8. Classification of posterior vitreous detachment.

    Science.gov (United States)

    Kakehashi, Akihiro; Takezawa, Mikiko; Akiba, Jun

    2014-01-01

    Diagnosing a posterior vitreous detachment (PVD) is important for predicting the prognosis and determining the indication for vitreoretinal surgery in many vitreoretinal diseases. This article presents both classifications of a PVD by slit-lamp biomicroscopy and of a shallow PVD by optical coherence tomography (OCT). By biomicroscopy, the vitreous condition is determined based on the presence or absence of a PVD. The PVD then is classified as either a complete posterior vitreous detachment (C-PVD) or a partial posterior vitreous detachment (P-PVD). A C-PVD is further divided into a C-PVD with collapse and a C-PVD without collapse, while a P-PVD is divided into a P-PVD with shrinkage of the posterior hyaloid membrane (P-PVD with shrinkage) and a P-PVD without shrinkage of the posterior hyaloid membrane (P-PVD without shrinkage). A P-PVD without shrinkage has a subtype characterized by vitreous gel attachment through the premacular hole in a posterior hyaloid membrane to the macula (P-PVD without shrinkage [M]). By OCT, a shallow PVD is classified as the absence of a shallow PVD or as a shallow PVD. A shallow PVD is then subclassified as a shallow PVD without shrinkage of the posterior vitreous cortex, a shallow PVD with shrinkage of the posterior vitreous cortex, and a peripheral shallow PVD. A shallow PVD without shrinkage of the posterior vitreous cortex has two subtypes: an age-related shallow PVD and a perifoveal PVD associated with a macular hole.

  9. Cortical projection topography of the human splenium: hemispheric asymmetry and individual differences.

    Science.gov (United States)

    Putnam, Mary Colvin; Steven, Megan S; Doron, Karl W; Riggall, Adam C; Gazzaniga, Michael S

    2010-08-01

    The corpus callosum is the largest white matter pathway in the human brain. The most posterior portion, known as the splenium, is critical for interhemispheric communication between visual areas. The current study employed diffusion tensor imaging to delineate the complete cortical projection topography of the human splenium. Homotopic and heterotopic connections were revealed between the splenium and the posterior visual areas, including the occipital and the posterior parietal cortices. In nearly one third of participants, there were homotopic connections between the primary visual cortices, suggesting interindividual differences in splenial connectivity. There were also more instances of connections with the right hemisphere, indicating a hemispheric asymmetry in interhemispheric connectivity within the splenium. Combined, these findings demonstrate unique aspects of human interhemispheric connectivity and provide anatomical bases for hemispheric asymmetries in visual processing and a long-described hemispheric asymmetry in speed of interhemispheric communication for visual information.

  10. Fatal atypical reversible posterior leukoencephalopathy syndrome: a case report

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    Golombeck Stefanie Kristin

    2013-01-01

    Full Text Available Abstract Introduction Reversible posterior leukoencephalopathy syndrome – a reversible subacute global encephalopathy clinically presenting with headache, altered mental status, visual symptoms such as hemianopsia or cortical blindness, motor symptoms, and focal or generalized seizures – is characterized by a subcortical vasogenic edema symmetrically affecting posterior brain regions. Complete reversibility of both clinical signs and magnetic resonance imaging lesions is regarded as a defining feature of reversible posterior leukoencephalopathy syndrome. Reversible posterior leukoencephalopathy syndrome is almost exclusively seen in the setting of a predisposing clinical condition, such as pre-eclampsia, systemic infections, sepsis and shock, certain autoimmune diseases, various malignancies and cytotoxic chemotherapy, transplantation and concomitant immunosuppression (especially with calcineurin inhibitors as well as episodes of abrupt hypertension. We describe for the first time clinical, radiological and histological findings in a case of reversible posterior leukoencephalopathy syndrome with an irreversible and fatal outcome occurring in the absence of any of the known predisposing clinical conditions except for a hypertensive episode. Case presentation A 58-year-old Caucasian woman presented with a two-week history of subacute and progressive occipital headache, blurred vision and imbalance of gait and with no evidence for raised arterial blood pressure during the two weeks previous to admission. Her past medical history was unremarkable except for controlled arterial hypertension. Cerebral magnetic resonance imaging demonstrated cortical and subcortical lesions with combined vasogenic and cytotoxic edema atypical for both venous congestion and arterial infarction. Routine laboratory and cerebrospinal fluid parameters were normal. The diagnosis of reversible posterior leukoencephalopathy syndrome was established. Within hours after

  11. Word and face recognition deficits following posterior cerebral artery stroke

    DEFF Research Database (Denmark)

    Kuhn, Christina D.; Asperud Thomsen, Johanne; Delfi, Tzvetelina

    2016-01-01

    Abstract Recent findings have challenged the existence of category specific brain areas for perceptual processing of words and faces, suggesting the existence of a common network supporting the recognition of both. We examined the performance of patients with focal lesions in posterior cortical...... areas to investigate whether deficits in recognition of words and faces systematically co-occur as would be expected if both functions rely on a common cerebral network. Seven right-handed patients with unilateral brain damage following stroke in areas supplied by the posterior cerebral artery were...... included (four with right hemisphere damage, three with left, tested at least 1 year post stroke). We examined word and face recognition using a delayed match-to-sample paradigm using four different categories of stimuli: cropped faces, full faces, words, and cars. Reading speed and word length effects...

  12. CT perfusion imaging in the management of posterior reversible encephalopathy

    Energy Technology Data Exchange (ETDEWEB)

    Casey, S.O.; McKinney, A.; Teksam, M.; Liu, H.; Truwit, C.L. [Department of Radiology, University of Minnesota Medical School, 420 Delaware Street SE, Box 292, MN 55455, Minneapolis (United States)

    2004-04-01

    A 13-year-old girl with a renal transplant presented with hypertension and seizures. CT and MRI demonstrated typical bilateral parietal, occipital and posterior frontal cortical and subcortical edema, thought to represent posterior reversible encephalopathy syndrome. The cause was presumed to be hypertension. Antihypertensive therapy was started, lowering of the blood pressure in the range of 110-120 mmHg systolic. However, stable xenon (Xe) CT perfusion imaging revealed ischemia within the left parietal occipital region. The antihypertensive was adjusted which increased both the systolic and diastolic blood pressure by 31 mm Hg. The patient was re-imaged with Xe CT and was found to have resolution of the ischemic changes within the left parietal occipital region. In this report, we present a case in which stable Xe CT was used to monitor the degree of cerebral perfusion and guide titration of antihypertensive therapy. Such brain perfusion monitoring may have helped to prevent infarction of our patient. (orig.)

  13. Patterns of cortical thinning in nondemented Parkinson's disease patients

    Science.gov (United States)

    Uribe, Carme; Segura, Barbara; Baggio, Hugo Cesar; Abos, Alexandra; Marti, Maria Jose; Valldeoriola, Francesc; Compta, Yaroslau; Bargallo, Nuria

    2016-01-01

    ABSTRACT Background Clinical variability in the Parkinson's disease phenotype suggests the existence of disease subtypes. We investigated whether distinct anatomical patterns of atrophy can be identified in Parkinson's disease using a hypothesis‐free, data‐driven approach based on cortical thickness data. Methods T1‐weighted 3‐tesla MRI and a comprehensive neuropsychological assessment were performed in a sample of 88 nondemented Parkinson's disease patients and 31 healthy controls. We performed a hierarchical cluster analysis of imaging data using Ward's linkage method. A general linear model with cortical thickness data was used to compare clustering groups. Results We observed 3 patterns of cortical thinning in patients when compared with healthy controls. Pattern 1 (n = 30, 34.09%) consisted of cortical atrophy in bilateral precentral gyrus, inferior and superior parietal lobules, cuneus, posterior cingulate, and parahippocampal gyrus. These patients showed worse cognitive performance when compared with controls and the other 2 patterns. Pattern 2 (n = 29, 32.95%) consisted of cortical atrophy involving occipital and frontal as well as superior parietal areas and included patients with younger age at onset. Finally, in pattern 3 (n = 29, 32.95%), there was no detectable cortical thinning. Patients in the 3 patterns did not differ in disease duration, motor severity, dopaminergic medication doses, or presence of mild cognitive impairment. Conclusions Three cortical atrophy subtypes were identified in nondemented Parkinson's disease patients: (1) parieto‐temporal pattern of atrophy with worse cognitive performance, (2) occipital and frontal cortical atrophy and younger disease onset, and (3) patients without detectable cortical atrophy. These findings may help identify prognosis markers in Parkinson's disease. © 2016 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement

  14. Cortical thickness difference across the central sulcus visualized in the presence of vasogenic edema

    Energy Technology Data Exchange (ETDEWEB)

    Togao, Osamu [Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Maidashi 3-1-1, Higashi-ku, Fukuoka 812-8582 (Japan)], E-mail: togao@dr.hosp.kyushu-u.ac.jp; Yoshiura, Takashi; Mihara, Futoshi; Noguchi, Tomoyuki; Hiwatashi, Akio; Yamashita, Koji; Yoshitake, Tadamasa; Honda, Hiroshi [Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Maidashi 3-1-1, Higashi-ku, Fukuoka 812-8582 (Japan)

    2008-05-15

    Purpose: To confirm the cortical thickness difference across the central sulcus (CS) visualized in the presence of vasogenic edema on MRI. Materials and methods: T2-weighted images of 70 cerebral hemispheres showing vasogenic edema infiltrating into subcortical white matter around the CS were studied retrospectively. Two neuroradiologists measured the cortical thickness of the anterior and posterior banks of the CS, precentral sulci (PrCS), and postcentral sulci (PoCS). Additionally, we compared the cortical thickness of the anterior and posterior banks of each sulcus visually using a grading scale. Results: On T2-weighted images, the cerebral cortex was highlighted by a high signal-intensity vasogenic edema in the adjacent white matter, and its thickness was readily measurable. The unique cortical thickness difference between the anterior and posterior banks of the CS were confirmed with measurements of 2.67 and 1.48 mm (p < 0.0001). The cortical measurements across other cerebral sulci were 2.04 and 1.95 mm (NS) for the PrCS, and 1.67 and 1.77 mm (NS) for the PoCS. The cortical thickness ratios were 1.86 for the CS, 1.05 for the PrCS, and 0.96 for the PoCS. On visual evaluation, the anterior bank of the CS was thicker than the posterior bank in 93% (65/70). For the PrCS and PoCS, the thickness of the anterior and posterior banks appeared to be equal in over 70% of the patients. Conclusion: A prominent cortical thickness difference across the CS in the presence of vasogenic edema was confirmed. This finding is considered to facilitate the identification of the CS in patients with brain tumors.

  15. Spontaneous resorption of sub-retinal cortical lens material

    Directory of Open Access Journals (Sweden)

    Salil S Gadkari

    2014-01-01

    Full Text Available We report a rare case of retained sub-retinal cortical material, which underwent spontaneous resorption. Patient presented with a left eye traumatic retinal detachment with a large retinal tear and posteriorly dislocated cataractous lens. Vitrectomy, lensectomy, silicone oil injection, and endolaser were performed. A good visual result was achieved. The report draws attention to this condition and highlights possible technique for minimizing risk of this complication in similar cases.

  16. Posterior scleral tuberculoma: case report

    Directory of Open Access Journals (Sweden)

    Antonio Augusto Velasco e Cruz

    2011-02-01

    Full Text Available Posterior scleral tuberculoma formation is an extremely rare condition. The few reports on scleral involvement in tuberculosis refer to cases of anterior scleritis. In the present manuscript we describe a patient who had rheumatoid arthritis and developed a large posterior scleral tuberculoma. The lesion provoked retinal detachment and visual loss and was diagnosed only after enucleation due to a misdiagnosis of choroidal melanoma.

  17. 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

  18. Posterior Reversible Leukoencephalopathy Syndrome Associated with Pazopanib

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    Robert Foerster

    2013-04-01

    Full Text Available A 62-year-old female patient with metastatic renal cell carcinoma under third-line treatment with pazopanib for 8 weeks suddenly developed severe headaches, grand mal seizures and paresis of the left arm in combination with gait instability as well as nausea and vomiting during her vacation abroad. The emergency physician measured systolic blood pressure values over 300 mm Hg and suspected a stroke. The CT imaging without contrast agent in a local hospital did not show any pathologic findings despite bone metastases. The colleagues suspected cerebral metastases or meningeosis carcinomatosa and referred the patient to our department for further diagnostics and treatment planning. An MRI scan ruled out the suspected cerebral metastases or meningeosis carcinomatosa, but showed signs of reversible posterior leukoencephalopathy syndrome (RPLS in the form of band-like hyperintensities as a sign of cytotoxic edema in the gray and white matter of the left parietal lobe. The patient then reported that similar blood pressure values had been measured shortly after the start of a first-line therapy with sunitinib, so that we discontinued the current treatment with pazopanib. Within 6 days the neurologic symptoms vanished and the patient was discharged. An intermittent hypertension persisted. A follow-up MRI 3 weeks later showed an RPLS-typical cortical infarction in the affected area. RPLS should be considered as the actual reason for neurologic findings in hypertensive patients with known metastatic cancers under tyrosine kinase inhibitor therapy.

  19. Cognitive Control Signals in Posterior Cingulate Cortex

    Directory of Open Access Journals (Sweden)

    Benjamin eHayden

    2010-12-01

    Full Text Available Efficiently shifting between tasks is a central function of cognitive control. The role of the default network—a constellation of areas with high baseline activity that declines during task performance—in cognitive control remains poorly understood. We hypothesized that task switching demands cognitive control to shift the balance of processing towards the external world, and therefore predicted that switching between the two tasks would require suppression of activity of neurons within the CGp. To test this idea, we recorded the activity of single neurons in posterior cingulate cortex (CGp, a central node in the default network, in monkeys performing two interleaved tasks. As predicted, we found that basal levels of neuronal activity were reduced following a switch from one task to another and gradually returned to pre-switch baseline on subsequent trials. We failed to observe these effects in lateral intraparietal cortex (LIP, part of the dorsal fronto-parietal cortical attention network directly connected to CGp. These findings indicate that suppression of neuronal activity in CGp facilitates cognitive control, and suggest that activity in the default network reflects processes that directly compete with control processes elsewhere in the brain..

  20. Moderate Cortical Cooling Eliminates Thalamocortical Silent States during Slow Oscillation.

    Science.gov (United States)

    Sheroziya, Maxim; Timofeev, Igor

    2015-09-23

    Reduction in temperature depolarizes neurons by a partial closure of potassium channels but decreases the vesicle release probability within synapses. Compared with cooling, neuromodulators produce qualitatively similar effects on intrinsic neuronal properties and synapses in the cortex. We used this similarity of neuronal action in ketamine-xylazine-anesthetized mice and non-anesthetized mice to manipulate the thalamocortical activity. We recorded cortical electroencephalogram/local field potential (LFP) activity and intracellular activities from the somatosensory thalamus in control conditions, during cortical cooling and on rewarming. In the deeply anesthetized mice, moderate cortical cooling was characterized by reversible disruption of the thalamocortical slow-wave pattern rhythmicity and the appearance of fast LFP spikes, with frequencies ranging from 6 to 9 Hz. These LFP spikes were correlated with the rhythmic IPSP activities recorded within the thalamic ventral posterior medial neurons and with depolarizing events in the posterior nucleus neurons. Similar cooling of the cortex during light anesthesia rapidly and reversibly eliminated thalamocortical silent states and evoked thalamocortical persistent activity; conversely, mild heating increased thalamocortical slow-wave rhythmicity. In the non-anesthetized head-restrained mice, cooling also prevented the generation of thalamocortical silent states. We conclude that moderate cortical cooling might be used to manipulate slow-wave network activity and induce neuromodulator-independent transition to activated states. Significance statement: In this study, we demonstrate that moderate local cortical cooling of lightly anesthetized or naturally sleeping mice disrupts thalamocortical slow oscillation and induces the activated local field potential pattern. Mild heating has the opposite effect; it increases the rhythmicity of thalamocortical slow oscillation. Our results demonstrate that slow oscillation can be

  1. Cortical myoclonus and cerebellar pathology

    NARCIS (Netherlands)

    Tijssen, MAJ; Thom, M; Ellison, DW; Wilkins, P; Barnes, D; Thompson, PD; Brown, P

    2000-01-01

    Objective To study the electrophysiologic and pathologic findings in three patients with cortical myoclonus. In two patients the myoclonic ataxic syndrome was associated with proven celiac disease. Background: The pathologic findings in conditions associated with cortical myoclonus commonly involve

  2. Atrophy of the intestinal villi in a post-gastrectomy patient with severe iron deficiency anemia Atrofia de las vellosidades intestinales en un paciente postgastrectomizado con anemia ferropénica grave

    Directory of Open Access Journals (Sweden)

    A. Lizarraga

    2009-10-01

    Full Text Available Background & aims: Iron deficiency anemia is a common complication of gastric surgery that in certain patients can be refractory to treatment with oral iron and needs to be treated parenterally. Methods: A 48-year woman underwent gastric surgery for a gastric ulcer. She was referred to the nutrition unit for the study and treatment of a 3-year iron deficiency anemia refractory to oral iron supplementation. Blood tests, endoscopy and jejunal biopsy were made to study the case. Results: Intestinal villi atrophy in the absence of celiac disease was the result. She was treated with intravenous iron, resolving the villous atrophy and thus oral iron supplementation could be effective. Conclusion: This case illustrates that iron deficiency may cause villous atrophy. In this setting, parenteral iron administration is necessary to correct the haematological and non-hematological alterations associated with this deficiency.Introducción y objetivos: La anemia ferropénica es una complicación frecuente tras la cirugía gástrica que en algunos pacientes puede ser refractaria al tratamiento con hierro oral, siendo necesaria su administración por vía parenteral. Métodos: Presentamos el caso de una mujer de 48 años intervenida de gastrectomía para tratamiento de una úlcera gástrica. Fue remitida a la unidad de nutrición para estudio y tratamiento de una anemia ferropénica de 3 años de evolución refractaria al tratamiento con hierro oral. Para el estudio del caso se realizó analítica y endoscopia digestiva alta con biopsia yeyunal. Resultados: En el estudio realizado la paciente presentaba atrofia de la mucosa yeyunal en ausencia de enfermedad celíaca. Fue tratada con hierro intravenoso desapareciendo la atrofia intestinal, tras lo cual continuamos con suplementos de hierro por vía oral. Conclusión: Este caso ilustra que la deficiencia de hierro puede producir atrofia intestinal. Si esto ocurre, es necesario la suplementación de este metal

  3. Effect of pregnancy on autoregulation of cerebral blood flow in anterior versus posterior cerebrum.

    Science.gov (United States)

    Cipolla, Marilyn J; Bishop, Nicole; Chan, Siu-Lung

    2012-09-01

    Severe preeclampsia and eclampsia are associated with brain edema that forms preferentially in the posterior cerebral cortex possibly because of decreased sympathetic innervation of posterior cerebral arteries and less effective autoregulation during acute hypertension. In the present study, we examined the effect of pregnancy on the effectiveness of cerebral blood flow autoregulation using laser Doppler flowmetry and edema formation by wet:dry weight in acute hypertension induced by phenylephrine infusion in the anterior and posterior cerebrum from nonpregnant (n=8) and late-pregnant (n=6) Sprague-Dawley rats. In addition, we compared the effect of pregnancy on sympathetic innervation by tyrosine hydroxylase staining of posterior and middle cerebral arteries (n=5-6 per group) and endothelial and neuronal NO synthase expression using quantitative PCR (n=3 per group). In nonpregnant animals, there was no difference in autoregulation between the anterior and posterior cerebrum. However, in late-pregnant animals, the threshold of cerebral blood flow autoregulation was shifted to lower pressures in the posterior cerebrum, which was associated with increased neuronal NO synthase expression in the posterior cerebral cortex versus anterior. Compared with the nonpregnant state, pregnancy increased the threshold of autoregulation in both brain regions that was related to decreased expression of endothelial NO synthase. Lastly, acute hypertension during pregnancy caused greater edema formation in both brain cortices that was not attributed to changes in sympathetic innervation. These findings suggest that, although pregnancy shifted the cerebral blood flow autoregulatory curve to higher pressures in both the anterior and posterior cortices, it did not protect from edema during acute hypertension.

  4. Cortical Abnormalities in ADHD

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2003-12-01

    Full Text Available Grey-matter abnormalities at the cortical surface and regional brain size were mapped by high-resolution MRI and surface-based, computational image analytical techniques in a group of 27 children and adolescents with attention deficit hyperactivity disorder (ADHD and 46 controls, matched by age and sex, at the University of California at Los Angeles.

  5. Epidural hematomas of posterior fossa

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    Radulović Danilo

    2004-01-01

    Full Text Available Background. Posterior fossa epidural hematomas represent 7-14% of all traumatic intracranial epidural hematomas. They are most frequently encountered posttraumatic mass lesions in the posterior fossa. The aim of this study was to identify clinical features that could lead to the early diagnosis of posterior fossa epidural hematoma. Methods. Between 1980 and 2002, 28 patients with epidural hematoma of the posterior fossa were operated on at the Institute for Neurosurgery, Belgrade. Clinical course neuroradiological investigations, and the results of surgical treatment of the patients with posterior fossa epidural hematomas were analyzed retrospectively. Results. Almost two thirds of patients were younger than 16 years of age. In 20 cases injury was caused by a fall, in 6 cases by a traffic accident, and in 2 by the assault. Clinical course was subacute or chronic in two thirds of the patients. On the admission Glasgow Coma Scale was 7 or less in 9 injured, 8-14 in 14 injured, and 15 in 5 injured patients. Linear fracture of the occipital bone was radiographically evident in 19 patients, but was intraoperatively encountered in all the patients except for a 4-year old child. In 25 patients the diagnosis was established by computer assisted tomography (CAT and in 3 by vertebral angiography. All the patients were operated on via suboccipital craniotomy. Four injured patients who were preoperatively comatose were with lethal outcome. Postoperatively, 24 patients were with sufficient neurologic recovery. Conclusion. Posterior fossa epidural hematoma should be suspected in cases of occipital injury, consciousness disturbances, and occipital bone fracture. In such cases urgent CAT-scan is recommended. Early recognition early diagnosis, and prompt treatment are crucial for good neurological recovery after surgery.

  6. 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.

  7. 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.

  8. Indirect reduction of posterior wall fragment using a suture anchor in acetabular posterior wall fracture with posterior labral root tear.

    Science.gov (United States)

    Yoo, Je-Hyun; Chang, Jun-Dong; Lee, Ho-Won

    2015-02-01

    Posterior wall fractures, which are the most common type of acetabulum fracture, are frequently accompanied with an avulsion tear of the posterior labral root as well as hip dislocation due to the injury mechanism. In the treatment of these fractures with an avulsed posterior labral root attached to posterior wall fragment, the use of a suture anchor can induce indirect reduction of a posterior wall fragment as well as direct repair of a labral root tear simultaneously. We describe the simple and efficient technique using a suture anchor in posterior wall acetabular fractures and surgical outcomes of two cases treated with this technique.

  9. Prevention of posterior capsular opacification

    NARCIS (Netherlands)

    Nibourg, Lisanne M; Gelens, Edith; Kuijer, Roelof; Hooymans, Johanna Mm; van Kooten, Theo G; Koopmans, Steven A

    2015-01-01

    Posterior capsular opacification (PCO) is a common complication of cataract surgery. The development of PCO is due to a combination of the processes of proliferation, migration, and transdifferentiation of residual lens epithelial cells (LECs) on the lens capsule. In the past decades, various forms

  10. Cortical thinning in subcortical vascular dementia with negative 11C-PiB PET.

    Science.gov (United States)

    Kim, Chi Hun; Seo, Sang Won; Kim, Geon Ha; Shin, Ji Soo; Cho, Hanna; Noh, Young; Kim, Suk-Hui; Kim, Min Ji; Jeon, Seun; Yoon, Uicheul; Lee, Jong-Min; Oh, Seung Jun; Kim, Jae Seung; Kim, Sung Tae; Lee, Jae-Hong; Na, Duk L

    2012-01-01

    To determine the existence of cortical thinning in subcortical vascular dementia (SVaD) with a negative 11C-Pittsburgh compound B (PiB) positron emission tomography scan and to compare the topography of cortical thinning between PiB-negative SVaD and Alzheimer's disease (AD), we enrolled 24 patients with PiB(-) SVaD, 81 clinically probable AD individuals, and 72 normal cognitive controls. Compared with controls, cortical thinning in PiB(-) SVaD was most profound in the perisylvian area, medial prefrontal area, and posterior cingulate gyri, while the precuneus and medial temporal lobes were relatively spared. When the cortical thickness of AD and PiB(-) SVaD were directly compared, PiB(-) SVaD demonstrated significant cortical thinning in the bilateral inferior frontal, superior temporal gyri, and right medial frontal and orbitofrontal lobes, while AD showed significant cortical thinning in the right medial temporal region. SVaD without amyloid burden may lead to substantial cortical atrophy. Moreover, characteristic topography of cortical thinning in PiB(-) SVaD suggests different mechanisms of cortical thinning in PiB(-) SVaD and AD.

  11. 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

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

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    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. Purely Cortical Anaplastic Ependymoma

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    Flávio Ramalho Romero

    2012-01-01

    Full Text Available Ependymomas are glial tumors derived from ependymal cells lining the ventricles and the central canal of the spinal cord. It may occur outside the ventricular structures, representing the extraventicular form, or without any relationship of ventricular system, called ectopic ependymona. Less than fifteen cases of ectopic ependymomas were reported and less than five were anaplastic. We report a rare case of pure cortical ectopic anaplastic ependymoma.

  14. Rapid cortical dynamics associated with auditory spatial attention gradients.

    Science.gov (United States)

    Mock, Jeffrey R; Seay, Michael J; Charney, Danielle R; Holmes, John L; Golob, Edward J

    2015-01-01

    Behavioral and EEG studies suggest spatial attention is allocated as a gradient in which processing benefits decrease away from an attended location. Yet the spatiotemporal dynamics of cortical processes that contribute to attentional gradients are unclear. We measured EEG while participants (n = 35) performed an auditory spatial attention task that required a button press to sounds at one target location on either the left or right. Distractor sounds were randomly presented at four non-target locations evenly spaced up to 180° from the target location. Attentional gradients were quantified by regressing ERP amplitudes elicited by distractors against their spatial location relative to the target. Independent component analysis was applied to each subject's scalp channel data, allowing isolation of distinct cortical sources. Results from scalp ERPs showed a tri-phasic response with gradient slope peaks at ~300 ms (frontal, positive), ~430 ms (posterior, negative), and a plateau starting at ~550 ms (frontal, positive). Corresponding to the first slope peak, a positive gradient was found within a central component when attending to both target locations and for two lateral frontal components when contralateral to the target location. Similarly, a central posterior component had a negative gradient that corresponded to the second slope peak regardless of target location. A right posterior component had both an ipsilateral followed by a contralateral gradient. Lateral posterior clusters also had decreases in α and β oscillatory power with a negative slope and contralateral tuning. Only the left posterior component (120-200 ms) corresponded to absolute sound location. The findings indicate a rapid, temporally-organized sequence of gradients thought to reflect interplay between frontal and parietal regions. We conclude these gradients support a target-based saliency map exhibiting aspects of both right-hemisphere dominance and opponent process models.

  15. Posterior scleritis associated with systemic tuberculosis

    Directory of Open Access Journals (Sweden)

    Gupta Amit

    2003-01-01

    Full Text Available Infective isolated posterior scleritis is rare. We report a case of isolated posterior scleritis associated with histopathologically documented systemic tuberculosis, a hitherto unreported association. The patient responded well to a combination of oral corticosteroids with antituberculosis therapy.

  16. Classification of posterior vitreous detachment

    OpenAIRE

    Kakehashi A; Takezawa M; Akiba J

    2013-01-01

    Akihiro Kakehashi,1 Mikiko Takezawa,1 Jun Akiba21Department of Ophthalmology, Jichi Medical University, Saitama Medical Center, Saitama, 2Kanjodori Eye Clinic, Asahikawa, JapanAbstract: Diagnosing a posterior vitreous detachment (PVD) is important for predicting the prognosis and determining the indication for vitreoretinal surgery in many vitreoretinal diseases. This article presents both classifications of a PVD by slit-lamp biomicroscopy and of a shallow PVD by optical coherence tomography...

  17. The normal posterior atlantoaxial relationship

    Energy Technology Data Exchange (ETDEWEB)

    Lovelock, J.E. (Rochester General Hospital, NY (USA)); Schuster, J.A. (Rochester Univ. Medical Center, NY (USA))

    1991-02-01

    The relationship of the posterior aspects of the atlas and the axis were studied in 100 normal adult volunteers. The ratio of the height of the atlantal spinolaminar line to the atlantoaxial interspinous distance was found to be remarkably constant and was less than 2.0 in all men and women. This ratio should prove helpful in detecting hyperflexion injuries isolated to the atlantoaxial level. (orig.).

  18. 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...

  19. 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 appre......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...

  20. TMS investigations into the task-dependent functional interplay between human posterior parietal and motor cortex.

    Science.gov (United States)

    Koch, Giacomo; Rothwell, John C

    2009-09-14

    Transcranial magnetic stimulation (TMS) can be used in two different ways to investigate the contribution of cortical areas involved in grasp/reach movements in humans. It can produce "virtual lesions" that interfere with activity in particular cortical areas at specific times during a task, or it can be used in a twin coil design to test the excitability of cortical projections to M1 at different times during a task. The former method has described how cortical structures such as the ventral premotor cortex (PMv), dorsal premotor cortex (PMd) and the anterior intraparietal sulcus (aIPS) are important for specific aspects of reaching, grasping and lifting objects. In the latter method, a conditioning stimulus (CS) is first used to activate putative pathways to the motor cortex from, for example, posterior parietal cortex (PPC) or PMd, while a second, test stimulus (TS), delivered over the primary motor cortex a few ms later probes any changes in excitability that are produced by the input. Thus changes in the effectiveness of the conditioning pulse give an indication of how the excitability of the connection changes over time and during a specific task. Here we review studies describing the time course of operation of parallel intracortical circuits and cortico-cortical connections between the PMd, PMv, PPC and M1, thus demonstrating that functional interplay between these areas and the primary motor cortices is not fixed, but can change in a highly task-, condition- and time-dependent manner.

  1. Posterior Fossa Tumor in Children

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    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

  2. Dynamics of Electrocorticographic (ECoG) Activity in Human Temporal and Frontal Cortical Areas During Music Listening

    Science.gov (United States)

    2012-04-14

    REPORT Dynamics of electrocorticographic (ECoG) activity in human temporal and frontal cortical areas during music listening 14. ABSTRACT 16. SECURITY...information about the sound intensity of music . ECoG activity in the high gamma band recorded from the posterior part of the superior temporal 1. REPORT...ECoG) activity in human temporal and frontal cortical areas during music listening Report Title ABSTRACT Previous studies demonstrated that brain

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

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    Antônio Altenor Bessa de Queiroz

    2014-08-01

    Full Text Available 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 ligament (PCL was determined in each knee. The distances between the center of the tibial insertion of the PCL and the posterior tibial border (CB and between the center of the tibial insertion of the PCL and wires 1, 2 and 3 (CW1, CW2 and CW3 were measured.Results:In the dissected knees, we found the center of the tibial insertion of the PCL at 1.09 ± 0.06 cm from the posterior tibial border. The distances between the wires 1, 2 and 3 and the center of the tibial insertion of the PCL were respectively 1.01 ± 0.08, 0.09 ± 0.05 and 0.5 ± 0.05 cm.Conclusion:The guidewire exit point 10 mm distal in relation to the posterior crest of the tibia was the best position for attempting to reproduce the anatomical center of the PCL.

  4. 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.

  5. 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.

  6. Longitudinal changes in cortical thickness associated with normal aging.

    Science.gov (United States)

    Thambisetty, Madhav; Wan, Jing; Carass, Aaron; An, Yang; Prince, Jerry L; Resnick, Susan M

    2010-10-01

    Imaging studies of anatomic changes in regional gray matter volumes and cortical thickness have documented age effects in many brain regions, but the majority of such studies have been cross-sectional investigations of individuals studied at a single point in time. In this study, using serial imaging assessments of participants in the Baltimore Longitudinal Study of Aging (BLSA), we investigate longitudinal changes in cortical thickness during aging in a cohort of 66 older adults (mean age 68.78; sd. 6.6; range 60-84 at baseline) without dementia. We used the Cortical Reconstruction Using Implicit Surface Evolution CRUISE suite of algorithms to automatically generate a reconstruction of the cortical surface and identified twenty gyral based regions of interest per hemisphere. Using mixed effects regression, we investigated longitudinal changes in these regions over a mean follow-up interval of 8 years. The main finding in this study is that age-related decline in cortical thickness is widespread, but shows an anterior-posterior gradient with frontal and parietal regions, in general, exhibiting greater rates of decline than temporal and occipital. There were fewer regions in the right hemisphere showing statistically significant age-associated longitudinal decreases in mean cortical thickness. Males showed greater rates of decline in the middle frontal, inferior parietal, parahippocampal, postcentral, and superior temporal gyri in the left hemisphere, right precuneus and bilaterally in the superior parietal and cingulate regions. Significant nonlinear changes over time were observed in the postcentral, precentral, and orbitofrontal gyri on the left and inferior parietal, cingulate, and orbitofrontal gyri on the right.

  7. Regional vulnerability of longitudinal cortical association connectivity

    Directory of Open Access Journals (Sweden)

    Rafael Ceschin

    2015-01-01

    Full Text Available Preterm born children with spastic diplegia type of cerebral palsy and white matter injury or periventricular leukomalacia (PVL, are known to have motor, visual and cognitive impairments. Most diffusion tensor imaging (DTI studies performed in this group have demonstrated widespread abnormalities using averaged deterministic tractography and voxel-based DTI measurements. Little is known about structural network correlates of white matter topography and reorganization in preterm cerebral palsy, despite the availability of new therapies and the need for brain imaging biomarkers. Here, we combined novel post-processing methodology of probabilistic tractography data in this preterm cohort to improve spatial and regional delineation of longitudinal cortical association tract abnormalities using an along-tract approach, and compared these data to structural DTI cortical network topology analysis. DTI images were acquired on 16 preterm children with cerebral palsy (mean age 5.6 ± 4 and 75 healthy controls (mean age 5.7 ± 3.4. Despite mean tract analysis, Tract-Based Spatial Statistics (TBSS and voxel-based morphometry (VBM demonstrating diffusely reduced fractional anisotropy (FA reduction in all white matter tracts, the along-tract analysis improved the detection of regional tract vulnerability. The along-tract map-structural network topology correlates revealed two associations: (1 reduced regional posterior–anterior gradient in FA of the longitudinal visual cortical association tracts (inferior fronto-occipital fasciculus, inferior longitudinal fasciculus, optic radiation, posterior thalamic radiation correlated with reduced posterior–anterior gradient of intra-regional (nodal efficiency metrics with relative sparing of frontal and temporal regions; and (2 reduced regional FA within frontal–thalamic–striatal white matter pathways (anterior limb/anterior thalamic radiation, superior longitudinal fasciculus and cortical spinal tract

  8. Posterior commissure of the human larynx revisited.

    Science.gov (United States)

    Tucker, John A; Tucker, Sean T

    2010-05-01

    The existence of the posterior commissure (PC) of the human larynx has been disputed (Hirano M, Sato K, et al. The posterior glottis. Trans Am Laryngol Assoc. 1986;107:70-75). "The term posterior commissure has no relevance to anatomical structure. The term commissure means a joining together. The bilateral vocal folds never join at their posterior ends. The posterior aspect of the glottis is a wall. The posterior lateral aspect of the posterior glottis is also the lateral wall of the posterior glottis" (Hirano M, Sato K, et al. The posterior glottis. Trans Am Laryngol Assoc. 1986;107:70-75). This study is intended to clarify the development of anatomical and morphological aspects of the PC in conjunction with a clinical classification of the larynx in sagittal view. This study uses human embryo and fetal laryngeal sections from the Carnegie Collection of Human Embryos (the world standard) and whole organ laryngeal sections from the Tucker Laryngeal Fetal Collection. Correlation of histologic and gross anatomical structure is made with the Hirano et al atlas, the Vidić Photographic Atlas of the Human Body, and the O'Rahilly Embryonic Atlas. Embryologic data clearly describe and illustrate the posterior union of the cricoid cartilage with formation of the PC. The anatomical functional aspects of the posterior lateral cricoid lamina as the supporting buttress of the articulating arytenoid cartilages are illustrated.

  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. [Posterior Reversible Encephalopathy Syndrome Associated with Cancer Therapy].

    Science.gov (United States)

    Mitsuya, Koichi; Nakasu, Yoko; Hayashi, Nakamasa; Yasui, Hirofumi; Ikeda, Takashi; Kuji, Shiho; Onozawa, Yusuke; Endo, Masahiro

    2016-03-01

    Posterior reversible encephalopathy syndrome(PRES)is a subacute neurological syndrome typically manifesting with headache, cortical blindness, and seizures. This syndrome is associated with risk factors such as malignant hypertension, eclampsia, and renal failure. Numerous case reports depict its occurrence in cancer patients. The direct causal mechanisms of PRES in cancer patients have not yet been identified. Cytotoxic chemotherapy may cause direct endothelial damage, which would impact the blood brain barrier. Angiogenesis inhibitors also cause elevation in blood pressure;this is significant, because PRES onset may be solely related to hypertension. An increased number of case reports involving new molecular targeted agent suggests that incidence of PRES as an oncological emergency may increase in the future.

  11. Amyloid-β Associated Cortical Thinning in Clinically Normal Elderly

    Science.gov (United States)

    Becker, J Alex; Hedden, Trey; Carmasin, Jeremy; Maye, Jacqueline; Rentz, Dorene M; Putcha, Deepti; Fischl, Bruce; Greve, Douglas N; Marshall, Gad A; Salloway, Stephen; Marks, Donald; Buckner, Randy L; Sperling, Reisa A; Johnson, Keith A

    2011-01-01

    Objective Both amyloid-β (Aβ) deposition and brain atrophy are associated with Alzheimer's disease (AD) and the disease process likely begins many years before symptoms appear. We sought to determine whether clinically normal (CN) older individuals with Aβ deposition revealed by positron emission tomography (PET) imaging using Pittsburgh Compound B (PiB) also have evidence of both cortical thickness and hippocampal volume reductions in a pattern similar to that seen in AD. Methods A total of 119 older individuals (87 CN subjects and 32 patients with mild AD) underwent PiB PET and high-resolution structural magnetic resonance imaging (MRI). Regression models were used to relate PiB retention to cortical thickness and hippocampal volume. Results We found that PiB retention in CN subjects was (1) age-related and (2) associated with cortical thickness reductions, particularly in parietal and posterior cingulate regions extending into the precuneus, in a pattern similar to that observed in mild AD. Hippocampal volume reduction was variably related to Aβ deposition. Interpretation We conclude that Aβ deposition is associated with a pattern of cortical thickness reduction consistent with AD prior to the development of cognitive impairment. ANN NEUROL 2010; PMID:21437929

  12. Transient cortical blindness following vertebral angiography: a case report.

    Science.gov (United States)

    Lo, Lai Wan; Chan, Ho Fung; Ma, Ka Fai; Cheng, Lik Fai; Chan, Tony Kt

    2015-02-01

    Transient cortical blindness (TCB) is a rare but well-known complication of cerebral angiography. Its pathophysiology remains uncertain. We would like to report a case of TCB in a patient during a follow up vertebral angiogram for post-coil embolization of left posterior inferior cerebellar artery aneurysm. Patient's vision was resumed spontaneously within 24 hours after angiography, with no residual neurological deficit in subsequent clinical follow up. Multi-modality imaging evaluation including vertebral angiography, brain CT and MRI performed on same day are presented.

  13. Análise bioquímica das metaloproteases da matriz extracelular durante atrofia experimental das glândulas salivares submandibulares em ratos Analysis of the matrix metalloproteases in duct-ligated submandibular salivary glands of rats

    Directory of Open Access Journals (Sweden)

    Ana Paula de SOUZA

    1999-04-01

    Full Text Available O presente estudo teve por objetivo analisar a expressão das metaloproteases da matriz extracelular durante a atrofia experimental das glândulas submandibulares em ratos, causada pela obstrução do ducto excretor principal. Os zimogramas realizados com extratos das porções internas e externas das glândulas salivares normais e ligadas mostraram que as principais enzimas gelatinolíticas possuíam pesos moleculares variando entre 72 kDa e 65 kDa. A atividade dessas enzimas aumentou progressivamente até o período entre 5 e 10 dias após a ligação, decrescendo nos períodos subseqüentes. Foram também detectadas bandas migrando entre 92 kDa e 72 kDa, sendo essas enzimas detectadas em quantidades significativas apenas na região da cápsula da glândula, no período de 2 dias. A confirmação de que as enzimas detectadas eram metaloproteases foi feita pelo uso de inibidores específicos. Os resultados sugerem que as metaloproteases da matriz têm um papel importante na remodelação da matriz extracelular durante a atrofia experimental da glândula submandibular.The purpose of the present study was to analyze the expression of the major metalloproteases in normal and ligated glands. The major metalloproteases detected had a molecular weight ranging from 72 to 65 kDa. The gelatinolytic activity increased progressively reaching a peak between 5 and 10 days after ligation. Bands with molecular weight ranging from 92-80 kDa were also detected in the capsule of the gland. The 92-80 kDa enzymes were only detected 2 days after ligation. The activity of these enzymes was supressed by specific inhibitors. Our results show that matrix metalloproteases play an active role in the extensive remodeling of the connective tissue that occurs during the atrophy of the submandibular gland.

  14. 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.

  15. Hiperostosis cortical infantil

    OpenAIRE

    Salvador Javier Santos Medina; Orelvis Pérez Duerto

    2015-01-01

    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 mes...

  16. Cortical plasticity and rehabilitation.

    Science.gov (United States)

    Moucha, Raluca; Kilgard, Michael P

    2006-01-01

    The brain is constantly adapting to environmental and endogenous changes (including injury) that occur at every stage of life. The mechanisms that regulate neural plasticity have been refined over millions of years. Motivation and sensory experience directly shape the rewiring that makes learning and neurological recovery possible. Guiding neural reorganization in a manner that facilitates recovery of function is a primary goal of neurological rehabilitation. As the rules that govern neural plasticity become better understood, it will be possible to manipulate the sensory and motor experience of patients to induce specific forms of plasticity. This review summarizes our current knowledge regarding factors that regulate cortical plasticity, illustrates specific forms of reorganization induced by control of each factor, and suggests how to exploit these factors for clinical benefit.

  17. 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.

  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. Neuropathology of a fatal case of posterior reversible encephalopathy syndrome.

    Science.gov (United States)

    Kheir, John N; Lawlor, Michael W; Ahn, Edward S; Lehmann, Leslie; Riviello, James J; Silvera, V Michelle; McManus, Michael; Folkerth, Rebecca D

    2010-01-01

    The pathology of posterior reversible encephalopathy syndrome (PRES) is undefined, since it is rarely fatal and is biopsied in only exceptional circumstances. We describe rapidly progressive PRES following stem cell transplant for acute lymphoblastic leukemia. After development of altered mental status, this 8-year-old girl had T2 prolongation of the white matter in a posterior-dominant distribution, eventually developing cerebellar edema, hemorrhage, hydrocephalus, and herniation. Despite surgical and medical management, she died 36 hours later. At autopsy, the occipital and cerebellar white matter and focal occipital cortical gray matter showed a spectrum of microvascular changes, including dilated perivascular spaces containing proteinaceous exudates and macrophages, as well as fibrinoid necrosis and acute hemorrhage, in a distribution corresponding to the neuroimaging abnormalities and reminiscent of those seen in patients with acute hypertensive encephalopathy. Of note, similar microvascular changes were not seen in the kidney or other systemic sites. Thus, the findings indicate a brain-specific microvascular compromise as the substrate of PRES, at least in the rare instance of cases progressing to fatal outcome.

  20. 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.

  1. State-modulation of cortico-cortical connections underlying normal EEG alpha variants.

    Science.gov (United States)

    Cantero, J L; Atienza, M; Salas, R M

    Normal electroencephalographic (EEG) alpha variants appear during relaxed wakefulness with closed eyes, drowsiness period at sleep onset, and rapid eye movement (REM) sleep in bursts without arousal signals. Previous results revealed that fronto-occipital and fronto-frontal alpha coherences became weaker from wakefulness to drowsiness, and finally to REM sleep. The present work was aimed at determining whether a generalized or a unidirectional deactivation of the long fronto-occipital fasciculi, previously proposed to be involved in the alpha rhythm generation, could explain the above-mentioned results. Polynomial regression analyses, applied to the change of alpha coherence with distance along the antero-posterior axis, suggested that the anterior and posterior local circuits show a similar level of activation in all brain states. Bivariate partial correlation analyses between local alpha coherences revealed that such local circuits maintain a reciprocal dependency during wakefulness, but unidirectional during drowsiness (anterior-to-posterior, A-P) and REM sleep (posterior-to-anterior, P-A). From these findings, both anterior and posterior cortical structures are suggested as being involved in the generation of the three alpha variants. If the implication of a double cortical generation source (anterior and posterior) of alpha variants is assumed, these two generators seem to maintain a mutual inter-dependency during wakefulness, whereas during the transition to human sleep, the anterior areas work quite independently of the posterior regions. Finally, the occipital structures may be the driving force for the REM-alpha bursts generation, since involvement of frontal regions demonstrated a high dependence on the posterior neural circuits in the genesis of this sleep event.

  2. 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

    as in 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 right......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...

  3. Posterior lip traction caused by intravitreal gas

    Energy Technology Data Exchange (ETDEWEB)

    Lincoff, H.; Kreissig, I.

    1981-08-01

    Traction on the posterior edge of a large tear may be an irreparable consequence of an intraocular gas tamponade used in the first instance to treat the tear. In two of three patients treated with octofluorocyclobutane (C4F8) and perfluoromethane (CF4), redetachment of a retinal tear occurred as a result of traction on the posterior edge of the tear when, prior to the operation, the posterior edge seemed to be free of any traction. With redetachment, a membrane became visible between the anterior and posterior lips of the tear. The membrane was probably posterior hyaloid augmented by cellular proliferation. The gas bubble, which had been intended to press the retina against the pigment epithelium, probably brought the detached posterior hyaloid into contact with the retina as well, and an adhesion between the hyaloid and retina formed.

  4. Neural correlates of superior intelligence: stronger recruitment of posterior parietal cortex.

    Science.gov (United States)

    Lee, Kun Ho; Choi, Yu Yong; Gray, Jeremy R; Cho, Sun Hee; Chae, Jeong-Ho; Lee, Seungheun; Kim, Kyungjin

    2006-01-15

    General intelligence (g) is a common factor in diverse cognitive abilities and a major influence on life outcomes. Neuroimaging studies in adults suggest that the lateral prefrontal and parietal cortices play a crucial role in related cognitive activities including fluid reasoning, the control of attention, and working memory. Here, we investigated the neural bases for intellectual giftedness (superior-g) in adolescents, using fMRI. The participants consisted of a superior-g group (n = 18, mean RAPM = 33.9 +/- 0.8, >99%) from the national academy for gifted adolescents and the control group (n = 18, mean RAPM = 22.8 +/- 1.6, 60%) from local high schools in Korea (mean age = 16.5 +/- 0.8). fMRI data were acquired while they performed two reasoning tasks with high and low g-loadings. In both groups, the high g-loaded tasks specifically increased regional activity in the bilateral fronto-parietal network including the lateral prefrontal, anterior cingulate, and posterior parietal cortices. However, the regional activations of the superior-g group were significantly stronger than those of the control group, especially in the posterior parietal cortex. Moreover, regression analysis revealed that activity of the superior and intraparietal cortices (BA 7/40) strongly covaried with individual differences in g (r = 0.71 to 0.81). A correlated vectors analysis implicated bilateral posterior parietal areas in g. These results suggest that superior-g may not be due to the recruitment of additional brain regions but to the functional facilitation of the fronto-parietal network particularly driven by the posterior parietal activation.

  5. Efeito posterior em dieletricos solidos

    OpenAIRE

    Scarpa, Paulo Cesar do Nascimento

    1989-01-01

    Dissertação (mestrado) - Universidade Federal do Parana Resumo: A macro e a micro-estrutura dos materiais dielétricos são sensíveis a sua historia térmica, mecânica e elétrica. Foi estudada, do ponto de vista teórico e experimental, a teoria da resposta dielétrica de Curie-Schweidler-Gross, vista tanto pela abordagem da teoria de circuito como da teoria de campo. O assunto e visto dentro da teoria geral da relaxação dielétrica, particularmente o efeito posterior em materiais dielétricos só...

  6. 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

  7. Transient cortical blindness: a benign but devastating complication after coronary angiography and graft study.

    Science.gov (United States)

    Sridhar, Ganiga Srinivasaiah; Sadiq, Muhammad Athar; Wan Ahmad, Wan Azman; Supuramaniam, Chitra; Undok, Abdul Wahab; Abidin, Imran Zainal; Chee, Kok Han

    2014-10-01

    Transient cortical blindness after coronary angiography and bypass graft is a very rare complication. In this report we present the case of a 63-year-old man who developed transient cortical blindness within 30 minutes of coronary angioplasty and graft study, but subsequently recovered within 72 hours without any neurological deficit. A plain computed tomography brain scan showed bilateral symmetrical subarachnoid hyperdensities in the posterior cerebral circulation area suspicious of subarachnoid bleed. However, magnetic resonance imaging and magnetic resonance angiography scans were normal. Excess contrast volume causing direct neurotoxicity seems to be the most probable cause, but the exact mechanism is unclear.

  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. 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.

  10. 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.

  11. Analysis of Cortical Flow Models In Vivo

    Science.gov (United States)

    Benink, Hélène A.; Mandato, Craig A.; Bement, William M.

    2000-01-01

    Cortical flow, the directed movement of cortical F-actin and cortical organelles, is a basic cellular motility process. Microtubules are thought to somehow direct cortical flow, but whether they do so by stimulating or inhibiting contraction of the cortical actin cytoskeleton is the subject of debate. Treatment of Xenopus oocytes with phorbol 12-myristate 13-acetate (PMA) triggers cortical flow toward the animal pole of the oocyte; this flow is suppressed by microtubules. To determine how this suppression occurs and whether it can control the direction of cortical flow, oocytes were subjected to localized manipulation of either the contractile stimulus (PMA) or microtubules. Localized PMA application resulted in redirection of cortical flow toward the site of application, as judged by movement of cortical pigment granules, cortical F-actin, and cortical myosin-2A. Such redirected flow was accelerated by microtubule depolymerization, showing that the suppression of cortical flow by microtubules is independent of the direction of flow. Direct observation of cortical F-actin by time-lapse confocal analysis in combination with photobleaching showed that cortical flow is driven by contraction of the cortical F-actin network and that microtubules suppress this contraction. The oocyte germinal vesicle serves as a microtubule organizing center in Xenopus oocytes; experimental displacement of the germinal vesicle toward the animal pole resulted in localized flow away from the animal pole. The results show that 1) cortical flow is directed toward areas of localized contraction of the cortical F-actin cytoskeleton; 2) microtubules suppress cortical flow by inhibiting contraction of the cortical F-actin cytoskeleton; and 3) localized, microtubule-dependent suppression of actomyosin-based contraction can control the direction of cortical flow. We discuss these findings in light of current models of cortical flow. PMID:10930453

  12. 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

  13. Postoperative rehabilitation of the posterior cruciate ligament.

    Science.gov (United States)

    Edson, Craig J; Fanelli, Gregory C; Beck, John D

    2010-12-01

    Diagnosis and management of posterior cruciate ligament injuries has evolved, and now the treatment often includes surgical intervention. The purpose of this paper is to define the current approach to postsurgical management after the posterior cruciate ligament reconstruction, review conservative management, and discuss surgical outcomes using a specified program.

  14. Association between mandibular posterior alveolar morphology and growth pattern in a Chinese population with normal occlusion

    Institute of Scientific and Technical Information of China (English)

    Min HAN; Dong-xu LIU; Chun-ling WANG; Rong-yang WANG; Hong LIU; Xiu-juan ZHU; Fu-lan WEI; Tao LV; Na-na WANG; Li-hua HU; Guo-ju LI

    2013-01-01

    Objective:To investigate the relationship between growth patterns and mandibular posterior tooth-alveolar bone complex morphology in a Chinese population with normal occlusion.Methods:Forty-five patients with normal occlusion (23 males,22 females) were included in this study.Among these patients,20 displayed the vertical growth pattern,and 20 had the horizontal growth pattern,while the remaining patients displayed the average growth pattern.All of the patients underwent dental cone beam computed tomography (CBCT),which included the region of the mandibular posterior teeth and the alveolar.A linear regression analysis and a correlation analysis between the facial height index (FHI) and the alveolar bone morphology were performed.Results:The inclination of the molars,the thickness of the cortical bone,and the height of the mandibular bone differed significantly between patients with the horizontal growth pattern and those with the vertical growth pattern (P<0.05).Significant positive correlations were found between:the FHI and the inclination of the molars; the FHI and the thickness of the cortical bone; and the FHI and the height of the mandibular bone.Conclusions:The mandibular posterior tooth-alveolar bone complex morphology may be affected by growth patterns.

  15. [Suprasegmental effects of selective posterior rhizotomy].

    Science.gov (United States)

    Horínek, D; Tichý, M; Cerný, R; Vlková, J

    2004-01-01

    The occurrence of spasticity is most commonly attributed to the lack of presynaptic inhibition. Perinatal damage to the central nervous system, as it happens in cerebral palsy, leads to pathological reflex response both on segmental and polysegmental levels. It results not only in clinical signs typical for spasticity but also in alterations of brainstem function, such as dysarthria or congenital nystagmus. Selective posterior rhizotomy is a neurosurgical method, routinely used in the treatment of spasticity. The lumbosacral posterior roots are partially cut under perioperative neurophysiological control. The aim of the treatment is the reduction of afferentation for posterior horns resulting in a decrease of pathological reflex responses. Selective posterior rhizotomy consequently decreases lower limbs spasticity. The improvement of upper extremities fine skills, the improvement of speech and cognitive functions has been also observed after selective posterior rhizotomy. The possible pathophysiological explanations of these so-called suprasegmental effects are discussed in the article.

  16. Lumbar pedicle cortical bone trajectory screw

    Institute of Scientific and Technical Information of China (English)

    Song Tengfei; Wellington K Hsu; Ye Tianwen

    2014-01-01

    Objective The purpose of this study was to demonstrate the lumbar pedicle cortical bone trajectory (CBT) screw fixation technique,a new fixation technique for lumbar surgery.Data sources The data analyzed in this review are mainly from articles reported in PubMed published from 1994 to 2014.Study selection Original articles and critical reviews relevant to CBT technique and lumbar pedicle fixation were selected.Results CBT technique was firstly introduced as a new fixation method for lumbar pedicle surgery in 2009.The concepts,morphometric study,biomechanical characteristics and clinical applications of CBT technique were reviewed.The insertional point of CBT screw is located at the lateral point of the pars interarticularis,and its trajectory follows a caudocephalad path sagittally and a laterally directed path in the transverse plane.CBT technique can be used for posterior fixation during lumbar fusion procedures.This technique is a minimally invasive surgery,which affords better biomechanical stability,fixation strength and surgical safety.Therefore,CBT technique has the greatest benefit in lumbar pedicle surgery for patients with osteoporosis and obesity.Conclusion CBT technique is a better alternative option of lumbar pedicle fixation,especially for patients with osteoporosis and obesity.

  17. Continence after posterior sagittal anorectoplasty.

    Science.gov (United States)

    Langemeijer, R A; Molenaar, J C

    1991-05-01

    Posterior sagittal anorectoplasty (PSARP) was introduced in 1982 by Peña and De Vries as a new operation for patients with a high anorectal malformation. The degree of postoperative continence is reported to be high. During the past decade, too, new insights have been gained into the embryology of anorectal malformations. Evaluation of PSARP in relation to current understanding of the development and anatomy of the anorectum and the pelvic floor has led us to conclude that optimal continence cannot be expected. Fifty patients with a high anorectal malformation underwent PSARP between June 1983 and May 1990. Postoperative follow-up consisted of anamnesis (subjective) and electrostimulation, defecography, and anorectal manometry (objective). All patients are alive, and all but one are being evaluated regularly. Subjectively, the majority of patients were more or less incontinent, with soiling of pants at least once a day. On the basis of objective criteria, virtually all patients appeared to be incontinent, and in only one patient was the mechanism of defecation almost unimpaired after PSARP. From this study, we conclude that although PSARP provides a good aesthetic result, patients will never acquire normal continence.

  18. Hiperostosis cortical infantil

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    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

  19. 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

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    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

  20. Posterior labral injury in contact athletes.

    Science.gov (United States)

    Mair, S D; Zarzour, R H; Speer, K P

    1998-01-01

    Nine athletes (seven football offensive linemen, one defensive lineman, and one lacrosse player) were found at arthroscopy to have posterior labral detachment from the glenoid. In our series, this lesion is specific to contact athletes who engage their opponents with arms in front of the body. All patients had pain with bench pressing and while participating in their sport, diminishing their ability to play effectively. Conservative measures were ineffective in relieving their symptoms. Examination under anesthesia revealed symmetric glenohumeral translation bilaterally, without evidence of posterior instability. Treatment consisted of glenoid rim abradement and posterior labral repair with a bioabsorbable tack. All patients returned to complete at least one full season of contact sports and weightlifting without pain (minimum follow-up, > or = 2 years). Although many injuries leading to subluxation of the glenohumeral joint occur when an unanticipated force is applied, contact athletes ready their shoulder muscles in anticipation of impact with opponents. This leads to a compressive force at the glenohumeral joint. We hypothesize that, in combination with a posteriorly directed force at impact, the resultant vector is a shearing force to the posterior labrum and articular surface. Repeated exposure leads to posterior labral detachment without capsular injury. Posterior labral reattachment provides consistently good results, allowing the athlete to return to competition.

  1. Microsurgical management of posterior circulation aneurysms

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    SHI Xiang-en

    2012-02-01

    Full Text Available Objective To retrospectively analyze effective methods for surgical management of posterior circulation aneurysms. Methods There were 42 patients with posterior circulation aneurysms [26 cases of basilar aneurysm (27 aneurysms, 16 cases of vertebral aneurysm (17 aneurysms]. There were 15 patients underwent bypass surgery [4 external carotid artery-P2 segment of posterior cerebral artery (ECA-P2, 2 internal carotid artery-P2 segment of posterior cerebral artery (ICA-P2, 2 internal maxillary artery-P2 segment of posterior cerebral artery (IMA-P2, 2 intracranial segment of vertebral artery-extracranial segment of vertebral artery, 5 occipital artery-posterior inferior cerebellar artery (OA-PICA] and 27 patients underwent simple surgical clipping. Results Activities of daily life of 37 patients recovered to normal (14 patients with aneurysm on the top of basilar artery, 3 with aneurysm on the trunk of basilar artery, 9 with vertebral aneurysm, 5 with posterior inferior cerebellar artery aneurysm, 4 with aneurysm on the junction of P1-P2 segment of posterior cerebral artery, 1 with superior cerebellar artery, and 1 with anterior inferior cerebellar aneurysm. None of them occurred operation-related neurological dysfunction. The recovery rate was 88.09% . Among the other patients, 1 with aneurysm on the top of basilar artery presented severe signs and symptoms of neurological defect and cannot take care of oneself, 2 patients (1 with aneurysm on the top of basilar artery, 1 with aneurysm on the trunk of basilar artery occurred brain stem hemorrhage after operation, and died at perioperative period, 2 with vertebral aneurysm relapsed and was cured after treatment. Conclusion Posterior circulation aneurysm which is not suitable for surgical clipping can be treated with intra? and extra?cranial vessel bypass. It may avoid the risk of surgical clipping of aneurysm.

  2. Cortical Correlates of Fitts’ Law

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    Peter eIfft

    2011-12-01

    Full Text Available Fitts' law describes the fundamental trade-off between movement accuracy and speed: It states that the duration of reaching movements is a function of target size and distance. While Fitts' law has been extensively studied in ergonomics and has guided the design of human-computer interfaces, there have been few studies on its neuronal correlates. To elucidate sensorimotor cortical activity underlying Fitts’ law, we implanted two monkeys with multielectrode arrays in the primary motor (M1 and primary somatosensory (S1 cortices. The monkeys performed reaches with a joystick-controlled cursor towards targets of different size. The reaction time, movement time and movement velocity changed with target size, and M1 and S1 activity reflected these changes. Moreover, modifications of cortical activity could not be explained by changes of movement parameters alone, but required target size as an additional parameter. Neuronal representation of target size was especially prominent during the early reaction time period where it influenced the slope of the firing rate rise preceding movement initiation. During the movement period, cortical activity was mostly correlated with movement velocity. Neural decoders were applied to simultaneously decode target size and motor parameters from cortical modulations. We suggest using such classifiers to improve neuroprosthetic control.

  3. Human cortical control of hand movements: parietofrontal networks for reaching, grasping, and pointing.

    Science.gov (United States)

    Filimon, Flavia

    2010-08-01

    In primates, control of the limb depends on many cortical areas. Whereas specialized parietofrontal circuits have been proposed for different movements in macaques, functional neuroimaging in humans has revealed widespread, overlapping activations for hand and eye movements and for movements such as reaching and grasping. This review examines the involvement of frontal and parietal areas in hand and arm movements in humans as revealed with functional neuroimaging. The degree of functional specialization, possible homologies with macaque cortical regions, and differences between frontal and posterior parietal areas are discussed, as well as a possible organization of hand movements with respect to different spatial reference frames. The available evidence supports a cortical organization along gradients of sensory (visual to somatosensory) and effector (eye to hand) preferences.

  4. Impaired emotional processing in a patient with a left posterior insula-SII lesion.

    Science.gov (United States)

    Borg, Céline; Bedoin, Nathalie; Peyron, Roland; Bogey, Soline; Laurent, Bernard; Thomas-Antérion, Catherine

    2013-01-01

    The present case-report investigated the influence of a lesion in the left posterior insula-SII cortices on the processing of emotions. MB and 16 normal controls explicitly rated the valence and the intensity of both facial expressions and emotional words. In addition, they had to perform a number comparison task and a lexical decision task without focusing their attention on emotional components of stimuli. MB identified the valence of emotional words as well as the control group. Nevertheless, she provided higher intensity scores for disgusted words and her responses in the lexical decision task were significantly delayed for these stimuli. In addition, MB's response times were not differently influenced by the presence of irrelevant emotional faces. However, she explicitly identified fewer facial expressions of disgust and she assessed them as significantly less intense. This pattern of results contributes to highlight the psychological and behavioral disorders observed after a left posterior insular stroke.

  5. Convergence of posteriors for discretized log Gaussian Cox processes

    DEFF Research Database (Denmark)

    Waagepetersen, Rasmus Plenge

    2004-01-01

    In Markov chain Monte Carlo posterior computation for log Gaussian Cox processes (LGCPs) a discretization of the continuously indexed Gaussian field is required. It is demonstrated that approximate posterior expectations computed from discretized LGCPs converge to the exact posterior expectations...

  6. Personality functioning and the cortical midline structures--an exploratory FMRI study.

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    Stephan Doering

    Full Text Available OBJECTIVE: Recent neuroscience studies explored the neuronal mechanisms underlying our sense of self. Thereby the cortical midline structures and their anterior and posterior regions have been shown to be central. What remains unclear though is how both, self and cortical midline structures, are related to the identity of the self which is of central importance in especially personality disorders. METHODS: Conducting an exploratory study with a dimensional approach, we here compared subjects with high and low level of personality functioning and identity integration as measured in a standardized way in fMRI during both, emotion- and reward-related tasks. RESULTS: Low levels of personality functioning and identity integration were predicted by significantly decreased degrees of deactivation in the anterior and posterior cortical midline structures. CONCLUSIONS: Though exploratory our results show for the first time direct relationship between cortical midline structures and personality functioning in terms of identity integration. This does not only contribute to our understanding of the neuronal mechanism underlying self and identity but carries also major implications for the treatment of patients with personality disorders.

  7. Phonetically Irregular Word Pronunciation and Cortical Thickness in the Adult Brain

    Science.gov (United States)

    Blackmon, Karen; Barr, William B.; Kuzniecky, Ruben; DuBois, Jonathan; Carlson, Chad; Quinn, Brian T.; Blumberg, Mark; Halgren, Eric; Hagler, Donald J.; Mikhly, Mark; Devinsky, Orrin; McDonald, Carrie R.; Dale, Anders M.; Thesen, Thomas

    2010-01-01

    Accurate pronunciation of phonetically irregular words (exception words) requires prior exposure to unique relationships between orthographic and phonemic features. Whether such word knowledge is accompanied by structural variation in areas associated with orthographic-to-phonemic transformations has not been investigated. We used high resolution MRI to determine whether performance on a visual word-reading test composed of phonetically irregular words, the Wechsler Test of Adult Reading (WTAR), is associated with regional variations in cortical structure. A sample of 60 right-handed, neurologically intact individuals were administered the WTAR and underwent 3T volumetric MRI. Using quantitative, surface-based image analysis, cortical thickness was estimated at each vertex on the cortical mantle and correlated with WTAR scores while controlling for age. Higher scores on the WTAR were associated with thicker cortex in bilateral anterior superior temporal gyrus, bilateral angular gyrus/posterior superior temporal gyrus, and left hemisphere intraparietal sulcus. Higher scores were also associated with thinner cortex in left hemisphere posterior fusiform gyrus and central sulcus, bilateral inferior frontal gyrus, and right hemisphere lingual gyrus and supramarginal gyrus. These results suggest that the ability to correctly pronounce phonetically irregular words is associated with structural variations in cortical areas that are commonly activated in functional neuroimaging studies of word reading, including areas associated with grapheme-to–phonemic conversion. PMID:20302944

  8. Cortical myoclonus in Huntington's disease.

    Science.gov (United States)

    Thompson, P D; Bhatia, K P; Brown, P; Davis, M B; Pires, M; Quinn, N P; Luthert, P; Honovar, M; O'Brien, M D; Marsden, C D

    1994-11-01

    We describe three patients with Huntington's disease, from two families, in whom myoclonus was the predominant clinical feature. The diagnosis was confirmed at autopsy in two cases and by DNA analysis in all three. These patients all presented before the age of 30 years and were the offspring of affected fathers. Neurophysiological studies documented generalised and multifocal action myoclonus of cortical origin that was strikingly stimulus sensitive, without enlargement of the cortical somatosensory evoked potential. The myoclonus improved with piracetam therapy in one patient and a combination of sodium valproate and clonazepam in the other two. Cortical reflex myoclonus is a rare but disabling component of the complex movement disorder of Huntington's disease, which may lead to substantial diagnostic difficulties.

  9. TDCS increases cortical excitability: direct evidence from TMS-EEG.

    Science.gov (United States)

    Romero Lauro, Leonor J; Rosanova, Mario; Mattavelli, Giulia; Convento, Silvia; Pisoni, Alberto; Opitz, Alexander; Bolognini, Nadia; Vallar, Giuseppe

    2014-09-01

    Despite transcranial direct current stimulation (tDCS) is increasingly used in experimental and clinical settings, its precise mechanisms of action remain largely unknown. At a neuronal level, tDCS modulates the resting membrane potential in a polarity-dependent fashion: anodal stimulation increases cortical excitability in the stimulated region, while cathodal decreases it. So far, the neurophysiological underpinnings of the immediate and delayed effects of tDCS, and to what extent the stimulation of a given cerebral region may affect the activity of anatomically connected regions, remain unclear. In the present study, we used a combination of Transcranial Magnetic Stimulation (TMS) and Electroencephalography (EEG) in order to explore local and global cortical excitability modulation during and after active and sham tDCS. Single pulse TMS was delivered over the left posterior parietal cortex (PPC), before, during, and after 15 min of tDCS over the right PPC, while EEG was recorded from 60 channels. For each session, indexes of global and local cerebral excitability were obtained, computed as global and local mean field power (Global Mean Field Power, GMFP and Local Mean Field Power, LMFP) on mean TMS-evoked potentials (TEPs) for three temporal windows: 0-50, 50-100, and 100-150 msec. The global index was computed on all 60 channels. The local indexes were computed in six clusters of electrodes: left and right in frontal, parietal and temporal regions. GMFP increased, compared to baseline, both during and after active tDCS in the 0-100 msec temporal window. LMFP increased after the end of stimulation in parietal and frontal clusters bilaterally, while no difference was found in the temporal clusters. In sum, a diffuse rise of cortical excitability occurred, both during and after active tDCS. This evidence highlights the spreading of the effects of anodal tDCS over remote cortical regions of stimulated and contralateral hemispheres.

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

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    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.

  11. The effects of caffeine ingestion on cortical areas: functional imaging study.

    Science.gov (United States)

    Park, Chan-A; Kang, Chang-Ki; Son, Young-Don; Choi, Eun-Jung; Kim, Sang-Hoon; Oh, Seung-Taek; Kim, Young-Bo; Park, Chan-Woong; Cho, Zang-Hee

    2014-05-01

    The effect of caffeine as a cognitive enhancer is well known; however, caffeine-induced changes in the cortical regions are still not very clear. Therefore, in this study, we conducted an investigation of the activation and deactivation with blood-oxygenation-level-dependent (BOLD) functional magnetic resonance imaging (fMRI) and of metabolic activity change with positron emission tomography (PET) in the human brain. Fourteen healthy subjects performed a visuomotor task inducing attention with 3T MRI, and PET imaging was also carried out in seven subjects to determine the cerebral glucose metabolic changes of caffeine at rest. The result by fMRI showed increased BOLD activation in the left cerebellum, putamen, insula, thalamus and the right primary motor cortex, and decreased BOLD deactivation in the posterior medial and the left posterior lateral cortex. Also, the resting state PET data showed reduced metabolic activity in the putamen, caudate nucleus, insula, pallidum and posterior medial cortex. The common cortical regions between fMRI and PET, such as putamen, insula and posterior medial cortex, where significant changes occurred after caffeine ingestion, are well known to play an important role in cognitive function like attention. This result suggests that the effect of caffeine as a cognitive enhancer is derived by modulating the attentional areas.

  12. Posterior circulation revascularization to manage vertebrobasilar occlusion

    Directory of Open Access Journals (Sweden)

    SHANG Yan-guo

    2012-06-01

    Full Text Available Objective To discuss the technique and effect of posterior circulation revascularization to manage vertebrobasilar occlusion. Methods Nine patients with vertebrobasilar occlusion were treated by using occipital artery-posterior inferior cerebellar artery bypass, superficial temporal artery-superior cerebellar artery bypass, superficial temporal artery-posterior cerebral artery bypass and occipital artery-vertebral artery bypass with radial artery graft. Results Intraoperative indocyanine green angiography showed all the bypass arteries were patent. Postoperative DSA or CTA showed bypass arteries patent in 8 patients, among whom seven patients got obvious improvement on MR or CT perfusion. One patient died of heart failure on the 15th day postoperative. During the follow-up of eight patients, no stroke reoccurred, four patients got back to nearly normal life. Conclusion Most of the patients with vertebrobasilar occlusion could benefit from the posterior circulation revascularization, which should be confirmed by randomized controlled clinical trials in the future.

  13. Posterior alien hand syndrome: case report

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    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.)

  14. Horizontal integration and cortical dynamics.

    Science.gov (United States)

    Gilbert, C D

    1992-07-01

    We have discussed several results that lead to a view that cells in the visual system are endowed with dynamic properties, influenced by context, expectation, and long-term modifications of the cortical network. These observations will be important for understanding how neuronal ensembles produce a system that perceives, remembers, and adapts to injury. The advantage to being able to observe changes at early stages in a sensory pathway is that one may be able to understand the way in which neuronal ensembles encode and represent images at the level of their receptive field properties, of cortical topographies, and of the patterns of connections between cells participating in a network.

  15. Grid cells and cortical representation.

    Science.gov (United States)

    Moser, Edvard I; Roudi, Yasser; Witter, Menno P; Kentros, Clifford; Bonhoeffer, Tobias; Moser, May-Britt

    2014-07-01

    One of the grand challenges in neuroscience is to comprehend neural computation in the association cortices, the parts of the cortex that have shown the largest expansion and differentiation during mammalian evolution and that are thought to contribute profoundly to the emergence of advanced cognition in humans. In this Review, we use grid cells in the medial entorhinal cortex as a gateway to understand network computation at a stage of cortical processing in which firing patterns are shaped not primarily by incoming sensory signals but to a large extent by the intrinsic properties of the local circuit.

  16. Complications of acute posterior vitreous detachment.

    Science.gov (United States)

    Kanski, J J

    1975-07-01

    Of 201 patients whose presenting symptoms were acute entoptic phenomena or photopsia, or both, 150 patients had posterior vitreous detachment; 69 patients (46%) had retinal breaks; 18 (12%) had a vitreous hemorrhage without detectable retinal breaks; and two (1.3%) had peripheral retinal hemorrhages without retinal breaks or vitreous hemorrhage. Retinal breaks that occur in eyes in conjunction with acute posterior vitreous detachment are potentially dangerous and there is a possibility of delayed break formation.

  17. Posterior cruciate ligament and posterolateral corner reconstruction.

    Science.gov (United States)

    Fanelli, Gregory C; Edson, Craig J; Reinheimer, Kristin N; Garofalo, Raffaele

    2007-12-01

    The keys to successful posterior cruciate ligament reconstruction are to identify and treat all pathology, use strong graft material, accurately place tunnels in anatomic insertion sites, minimize graft bending, use a mechanical graft-tensioning device, use primary and backup graft fixation, and employ the appropriate postoperative rehabilitation program. Adherence to these technical points results in successful single and double bundle arthroscopic transtibial tunnel posterior cruciate ligament reconstruction documented with stress radiography, arthrometer, knee ligament rating scales, and patient satisfaction measurements.

  18. Paroxysmal kinesigenic dyskinesia : Cortical or non-cortical origin

    NARCIS (Netherlands)

    van Strien, Teun W.; van Rootselaar, Anne-Fleur; Hilgevoord, Anthony A. J.; Linssen, Wim H. J. P.; Groffen, Alexander J. A.; Tijssen, Marina A. J.

    2012-01-01

    Paroxysmal kinesigenic dyskinesia (PKD) is characterized by involuntary dystonia and/or chorea triggered by a sudden movement. Cases are usually familial with an autosomal dominant inheritance. Hypotheses regarding the pathogenesis of PKD focus on the controversy whether PKD has a cortical or non-co

  19. Age-Dependent Cortical Thinning of Peripheral Visual Field Representations in Primary Visual Cortex.

    Science.gov (United States)

    Griffis, Joseph C; Burge, Wesley K; Visscher, Kristina M

    2016-01-01

    The cerebral cortex changes throughout the lifespan, and the cortical gray matter in many brain regions becomes thinner with advancing age. Effects of aging on cortical thickness (CT) have been observed in many brain regions, including areas involved in basic perceptual functions such as processing visual inputs. An important property of early visual cortices is their topographic organization-the cortical structure of early visual areas forms a topographic map of retinal inputs. Primary visual cortex (V1) is considered to be the most basic cortical area in the visual processing hierarchy, and is topographically organized from posterior (central visual representation) to anterior (peripheral visual representation) along the calcarine sulcus. Some studies have reported strong age-dependent cortical thinning in portions of V1 that likely correspond to peripheral visual representations, while there is less evidence of substantial cortical thinning in central V1. However, the effect of aging on CT in V1 as a function of its topography has not been directly investigated. To address this gap in the literature, we estimated the CT of different eccentricity sectors in V1 using T1-weighted MRI scans acquired from groups of healthy younger and older adults, and then assessed whether between-group differences in V1 CT depended on cortical eccentricity. These analyses revealed age-dependent cortical thinning specific to peripheral visual field representations in anterior portions of V1, but did not provide evidence for age-dependent cortical thinning in other portions of V1. Additional analyses found similar effects when analyses were restricted to the gyral crown, sulcul depth and sulcul wall, indicating that these effects are not likely due to differences in gyral/sulcul contributions to our regions of interest (ROI). Importantly, this finding indicates that age-dependent changes in cortical structure may differ among functionally distinct zones within larger canonical

  20. Spatio-temporal extension in site of origin for cortical calretinin neurons in primates

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    Ana eHladnik

    2014-06-01

    Full Text Available The vast majority of cortical GABAergic neurons can be defined by parvalbumin, somatostatin or calretinin expression. In most mammalians parvalbumin and somatostatin interneurons have constant proportions, each representing 5-7% of the total neuron number. In contrast, there is a 3 fold increase in the proportion of calretinin interneurons, which do not exceed 4% in rodents and reach 12% in higher order areas of primate cerebral cortex. In rodents almost all parvalbumin and somatostatin interneurons originate from the medial part of the subpallial proliferative structure, the ganglionic eminence (GE, while almost all calretinin interneurons originate from its caudal part. The spatial pattern of cortical GABAergic neurons origin from the GE is preserved in the monkey and human brain. However, it could be expected that the evolution is changing developmental rules to enable considerable expansion of calretinin interneuron population. During the early fetal period in primates cortical GABAergic neurons are almost entirely generated in the subpallium, as in rodents. Already at that time the primate caudal ganglionic eminence (CGE shows a relative increase in size and production of calretinin interneurons. During the second trimester of gestation, that is the main neurogenetic stage in primates without clear correlates found in rodents, the pallial production of cortical GABAergic neurons together with the extended persistence of the GE is observed. We propose that the CGE could be the main source of calretinin interneurons for the posterior and lateral cortical regions, but not for the frontal cortex. The associative granular frontal cortex represents around one third of the cortical surface and contains almost half of cortical calretinin interneurons. The majority of calretinin interneurons destined for the frontal cortex could be generated in the pallium, especially in the newly evolved outer subventricular zone that becomes the main pool of

  1. 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.

  2. Face activated neurodynamic cortical networks.

    Science.gov (United States)

    Susac, Ana; Ilmoniemi, Risto J; Ranken, Doug; Supek, Selma

    2011-05-01

    Previous neuroimaging studies have shown that complex visual stimuli, such as faces, activate multiple brain regions, yet little is known on the dynamics and complexity of the activated cortical networks during the entire measurable evoked response. In this study, we used simulated and face-evoked empirical MEG data from an oddball study to investigate the feasibility of accurate, efficient, and reliable spatio-temporal tracking of cortical pathways over prolonged time intervals. We applied a data-driven, semiautomated approach to spatio-temporal source localization with no prior assumptions on active cortical regions to explore non-invasively face-processing dynamics and their modulation by task. Simulations demonstrated that the use of multi-start downhill simplex and data-driven selections of time intervals submitted to the Calibrated Start Spatio-Temporal (CSST) algorithm resulted in improved accuracy of the source localization and the estimation of the onset of their activity. Locations and dynamics of the identified sources indicated a distributed cortical network involved in face processing whose complexity was task dependent. This MEG study provided the first non-invasive demonstration, agreeing with intracranial recordings, of an early onset of the activity in the fusiform face gyrus (FFG), and that frontal activation preceded parietal for responses elicited by target faces.

  3. Correlations between brain cortical thickness and cutaneous pain thresholds are atypical in adults with migraine.

    Directory of Open Access Journals (Sweden)

    Todd J Schwedt

    Full Text Available BACKGROUND/OBJECTIVE: Migraineurs have atypical pain processing, increased expectations for pain, and hypervigilance for pain. Recent studies identified correlations between brain structure and pain sensation in healthy adults. The objective of this study was to compare cortical thickness-to-pain threshold correlations in migraineurs to healthy controls. We hypothesized that migraineurs would have aberrant relationships between the anatomical neurocorrelates of pain processing and pain thresholds. METHODS: Pain thresholds to cutaneously applied heat were determined for 31 adult migraineurs and 32 healthy controls. Cortical thickness was determined from magnetic resonance imaging T1-weighted sequences. Regional cortical thickness-to-pain threshold correlations were determined for migraineurs and controls separately using a general linear model whole brain vertex-wise analysis. A pain threshold-by-group interaction analysis was then conducted to estimate regions where migraineurs show alterations in the pain threshold-to-cortical thickness correlations relative to healthy controls. RESULTS: Controls had negative correlations (p<0.01 uncorrected between pain thresholds and cortical thickness in left posterior cingulate/precuneus, right superior temporal, right inferior parietal, and left inferior temporal regions, and a negative correlation (p<0.01 Monte Carlo corrected with a left superior temporal/inferior parietal region. Migraineurs had positive correlations (p<0.01 uncorrected between pain thresholds and cortical thickness in left superior temporal/inferior parietal, right precuneus, right superior temporal/inferior parietal, and left inferior parietal regions. Cortical thickness-to-pain threshold correlations differed between migraine and control groups (p<0.01 uncorrected for right superior temporal/inferior parietal, right precentral, left posterior cingulate/precuneus, and right inferior parietal regions and (p<0.01 Monte Carlo corrected

  4. Posterior interosseous free flap: various types.

    Science.gov (United States)

    Park, J J; Kim, J S; Chung, J I

    1997-10-01

    The posterior interosseous artery is located in the intermuscular septum between the extensor carpi ulnaris and extensor digiti minimi muscles. The posterior interosseous artery is anatomically united through two main anastomoses: one proximal (at the level of the distal border of the supinator muscle) and one distal (at the most distal part of the interosseous space). In the distal part, the posterior interosseous artery joins the anterior interosseous artery to form the distal anastomosis between them. The posterior interosseous flap can be widely used as a reverse flow island flap because it is perfused by anastomoses between the anterior and the posterior interosseous arteries at the level of the wrist. The flap is not reliable whenever there is injury to the distal forearm or the wrist. To circumvent this limitation and to increase the versatility of this flap, we have refined its use as a direct flow free flap. The three types of free flaps used were (1) fasciocutaneous, (2) fasciocutaneous-fascia, and (3) fascia only. Described are 23 posterior interosseous free flaps: 13 fasciocutaneous flaps, 6 fasciocutaneous-fascial flaps, and 4 fascial flaps. There were 13 sensory flaps using the posterior antebrachial cutaneous nerve. The length and external diameter of the pedicle were measured in 35 cases. The length of the pedicle was on average 3.5 cm (range, 3.0 to 4.0 cm) and the external diameter of the artery averaged 2.2 mm (range, 2.0 to 2.5 mm). The hand was the recipient in 21 patients, and the foot in 2. All 23 flaps covered the defect successfully.

  5. Posterior reversible leukoencephalopathy syndrome in children with hematologic disorders

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    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.

  6. Sindrome de encefalopatia posterior reversível: relato de caso Reversible posterior encephalopathy syndrome: case report

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    Francine Judith Freitas Fernandes

    2002-09-01

    Full Text Available A encefalopatia posterior reversível é uma síndrome aguda / subaguda geralmente causada pela encefalopatia hipertensiva, eclâmpsia, neurotoxicidade a ciclosporina-A, encefalopatia urêmica e púrpura trombocitopênica trombótica.. A maioria dos pacientes apresenta elevação acentuada dos níveis tensionais outros, níveis moderados ou normais. Os sintomas são progressivos e compreendem cefaléia, diminuição do nível de consciência, crises epilépticas e distúrbios visuais. A sintomatologia regride completamente se corrigidas em tempo as causas determinantes, caso contrário, podem instalar-se danos irreversíveis como a cegueira cortical e morte. A tomografia computadorizada (TC e, sobretudo, a ressonância magnética (RM contribuem para o diagnóstico. Tais métodos evidenciam edema da substância branca e cinzenta, principalmente das regiões parieto-occipitais. Os achados podem apresentar dificuldade no diagnóstico, hoje superado em parte, com a técnica de difusão pela RM, capaz de diferenciar edema citotóxico de vasogênico. Apresentamos um caso de encefalopatia posterior reversível decorrente de encefalopatia hipertensiva estudada com TC e RM.The posterior reversible leukoencephalopathy syndrome (PRES is a recently proposed cliniconeuroradiologic entity.The most common causes of PRES are hypertensive encephalopathy, eclampsia, cyclosporin A neurotoxicity and the uremic encephalopathies.Most patients are markedly hypertensive at presentation, although some have only middly elevated or even normal blood pressure. Symptoms may include headache, nausea , vomiting, altered mental status, seizures,stupor, and visual disturbances. On CT and MR studies, edema has been reported in a relatively symmetrical pattern, typically in the subcortical white matter and occasionally in the cortex of the occipital and parietal lobes. These often striking imaging findings usually are resolved on follow-up studies obtained after appropiate

  7. Interhemispheric transfalcine approach and awake cortical mapping for resection of peri-atrial gliomas associated with the central lobule.

    Science.gov (United States)

    Malekpour, Mahdi; Cohen-Gadol, Aaron A

    2015-02-01

    Medial posterior frontal and parietal gliomas extending to the peri-atrial region are difficult to reach surgically because of the working angle required to expose the lateral aspect of the tumor and the proximity of the tumor to the sensorimotor lobule; retraction of the sensorimotor cortex may lead to morbidity. The interhemispheric transfalcine approach is favorable and safe for resection of medial hemispheric tumors adjacent to the falx cerebri, but the literature on this approach is scarce. Awake cortical mapping using this operative route for tumors associated with the sensorimotor cortex has not been previously reported to our knowledge. We present the first case of a right medial posterior frontoparietal oligoastrocytoma that was resected through the interhemispheric transfalcine approach using awake cortical and subcortical mapping. Through a contralateral frontoparietal craniotomy, we excised a section of the falx and exposed the contralateral medial hemisphere. Cortical stimulation allowed localization of the supplementary motor cortex, and suprathreshold stimulation mapping excluded the primary motor cortex corresponding to the leg area. Gross total tumor resection was accomplished without any intraoperative or postoperative deficits. Awake cortical mapping using the contralateral transfalcine approach allows a "cross-court" operative route to map functional cortices and resect peri-atrial low-grade gliomas. This technique can minimize the otherwise necessary retraction on the ipsilateral hemisphere through an ipsilateral craniotomy.

  8. 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.

  9. Posterior Chamber Hemorrhage during Fluorescein Angiography

    Directory of Open Access Journals (Sweden)

    Manuel A. P. Vilela

    2015-01-01

    Full Text Available This paper provides the first reported case of acute posterior chamber hemorrhage during fluorescein angiography (FA. This is a case review with serial color photographs of the anterior segment. A 76-year-old male was referred for angiographic control of age-related macular degeneration. He was pseudophakic OU, BCVA 20/40 OU. He had mild hypertension, but not diabetes. He had had two previous angiograms without adverse effects. Difficulty was experienced in obtaining the images owing to a progressive reduction in the transparency of the media. A dense hemorrhage in the posterior chamber of the right eye was found, involving the visual axis. Thorough biomicroscopy, gonioscopy, and ultrasonic biomicroscopy showed that part of one of the haptics of the right intraocular lens (IOL was touching and tearing the posterior face of the iris, without any visible synechiae, iris, or angle neovascularization. Anterior segment FA and posterior ultrasonography were normal. No similar case has been described in the literature involving dense progressive bleeding located in the capsular bag and posterior chamber, without any detectable triggering ocular event other than mydriasis and fluorescein injection. Contact of the iris or sulcus with part of the intraocular lens, aggravated by the intense use of mydriatics during the FA procedure, probably caused bleeding to happen.

  10. Advances and disputes of posterior malleolus fracture

    Institute of Scientific and Technical Information of China (English)

    FU Su; ZOU Zhen-yu; MEI Gang; JIN Dan

    2013-01-01

    Objective The objective of this article is to summarize the development of evaluation and treatment of posterior malleolus fracture (PMF).Data sources Data used in this review were mainly from English literature of PubMed data base.Study selection Articles were included in this review if they were related to the PMF or trimalleolar fracture.Results No consensus was found regarding what sizes of posterior malleolus fragments would lead to ankle instability thus affecting prognosis and should be fixed.Ⅹ-ray measurement is unreliable,while CT scan is widely recommended and it can recognize the occult posterior malleolus fractures associated with tibia shaft fractures,which are always undetected previously.Direct posterior malleolus fixation is suitable to stabilize syndesmotic injury.The basic and clinical researches support direct reduction and buttress plate fixation of posterior malleolus fracture through the posterolateral approach.Operative indications and timing of weight bearing are still in discussion.Conclusions Knowing whether ankle instability occurs and the proper methods to diagnose,evaluate,and operate can help manage the fracture.Further biomechanical research on ankle stability and clinical study to compare various treatment methods are required.

  11. Cathodal transcranial direct current stimulation of the posterior parietal cortex reduces steady-state postural stability during the effect of light touch.

    Science.gov (United States)

    Ishigaki, Tomoya; Imai, Ryota; Morioka, Shu

    2016-09-28

    Touching a stable object with a fingertip using slight force (mechanical support, which is referred to as the effect of light touch (LT). In the neural mechanism of the effect of LT, the specific contribution of the cortical brain activity toward the effect of LT remains undefined, particularly the contribution toward steady-state postural sway. The aim of the present study was to investigate the cortical region responsible for the reduction of postural sway in response to the effect of LT. Active LT was applied with the right fingertip and transcranial direct current stimulation (sham or cathodal) was applied to the left primary sensorimotor cortex or the left posterior parietal cortex in the two groups. The experiments were conducted using a single-blind sham-controlled crossover design. Steady-state postural sway was compared with the factors of transcranial direct current stimulation (sham or cathodal) and time (pre or post). In the results, the effect of LT reduced postural stability in the mediolateral direction after cathodal transcranial direct current stimulation of the left posterior parietal cortex. No effect was observed after stimulation of the left primary sensorimotor cortex. This indicates that the left posterior parietal cortex is partly responsible for the effect of LT when touching a fixed point with the right fingertip during suprapostural tasks, where posture is adjusted according to the precision requirements. Cortical processing of sensory integration for voluntary postural orientation in response to touch occurs in the posterior parietal cortex.

  12. 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.

  13. The bihemispheric posterior inferior cerebellar artery

    Energy Technology Data Exchange (ETDEWEB)

    Cullen, Sean P. [Brigham and Women' s Hospital and Children' s Hospital, Department of Radiology and Neurosurgery, Boston, MA (United States); Ozanne, Augustin; Alvarez, Hortensia; Lasjaunias, Pierre [Service de Neuroradiologie Diagnostic et Therapeutique, Hopital de Bicetre-Universite Paris-sud Orsay (France)

    2005-11-01

    Rarely, a solitary posterior inferior cerebellar artery (PICA) will supply both cerebellar hemispheres. We report four cases of this variant. We present a retrospective review of clinical information and imaging of patients undergoing angiography at our institution to identify patients with a bihemispheric PICA. There were four patients: three males and one female. One patient presented with a ruptured arteriovenous malformation, and one with a ruptured aneurysm. Two patients had normal angiograms. The bihemispheric PICA was an incidental finding in all cases. The bihemispheric vessel arose from the dominant left vertebral artery, and the contralateral posterior inferior cerebellar artery was absent or hypoplastic. In all cases, contralateral cerebellar supply arose from a continuation of the ipsilateral PICA distal to the choroidal point and which crossed the midline dorsal to the vermis. We conclude that the PICA may supply both cerebellar hemispheres. This rare anatomic variant should be considered when evaluating patients with posterior fossa neurovascular disease. (orig.)

  14. Preformed posterior stainless steel crowns: an update.

    Science.gov (United States)

    Croll, T P

    1999-02-01

    For almost 50 years, dentists have used stainless steel crowns for primary and permanent posterior teeth. No other type of restoration offers the convenience, low cost, durability, and reliability of such crowns when interim full-coronal coverage is required. Preformed stainless steel crowns have improved over the years. Better luting cements have been developed and different methods of crown manipulation have evolved. This article reviews stainless steel crown procedures for primary and permanent posterior teeth. Step-by-step placement of a primary molar stainless steel crown is documented and permanent molar stainless steel crown restoration is described. A method for repairing a worn-through crown also is reviewed.

  15. Transverse posterior element fractures associated with torsion

    Energy Technology Data Exchange (ETDEWEB)

    Abel, M.S.

    1989-01-01

    Six examples of a previously undescribed class of transverse vertebral element fractures are presented. These fractures differ from Chance and Smith fractures and their variants in the following respects: (1) the etiology is torsion and not flexion; (2) there is neither distraction of posterior ring fragments nor posterior ligament tears; (3) in contrast to Chance and Smith fractures, extension of the fracture into the vertebral body is absent or minimal; (4) the transverse process of the lumbar vertebra is avulsed at its base with a vertical fracture, not split horizontally. These fractures occur in cervical, lumbar, and sacral vertebrae in normal or compromised areas of the spine.

  16. Development of memory for spatial context: hippocampal and cortical contributions.

    Science.gov (United States)

    DeMaster, Dana; Pathman, Thanujeni; Ghetti, Simona

    2013-10-01

    The goal of the present study was to examine age-related differences in hippocampal and cortical contribution to episodic retrieval of spatial context in 3 age groups. Children ages 8-9 and 10-11 years old, and adults ages 18-25 (N=48) encoded black and white line drawings appearing either on the right side or the left side of a screen. Functional magnetic resonance imaging (fMRI) data were acquired while participants attempted to recall where each studied drawing had originally appeared. Correct recall of spatial source indicated successful episodic retrieval of spatial context. Activity in head and body of the hippocampus was associated with episodic retrieval in adults, but not in children. In children, individual differences in hippocampal activation for recognition predicted rates of correct spatial recall. Developmental differences were also found in regions in posterior parietal cortex, anterior prefrontal cortex, and insula. Overall, these results support the view that the development of episodic memory is supported by functional changes in the hippocampus as well as cortical regions.

  17. Residual stress around the cortical surface in bovine femoral diaphysis.

    Science.gov (United States)

    Yamada, Satoshi; Tadano, Shigeru

    2010-04-01

    Residual stress in living tissue plays an important role in mechanical strength. We have reported that residual stress exists in the bone tissue of a rabbit's tibiofibula. The purpose of this study is to measure the residual stress around the outer cortical region of bovine femoral diaphysis and to discuss the distribution of the stress. This work proposed the sin(2) psi method of X-ray diffraction to the measurement of residual stresses in bone tissue. In this method, residual stress can be estimated from the variation in the interplanar spacings orientated to a number of directions without the lattice strain in the stress direction. Four-point bending tests of strip specimens taken from bovine femoral diaphysis were carried out during X-ray irradiation in advance. In the proximal, middle, and distal sections of bovine femoral diaphyses, the residual stresses at the cortical surface were measured using characteristic Mo-Kalpha X-rays. The bending tests of strip specimens with X-ray irradiation showed that the method could reliably estimate residual stresses in the bone tissue. The residual stress of the bone axial direction was larger than that of the circumferential direction. The stresses in the middle part of five diaphyses along the bone axial direction were tensile. The maximum stress was 162 MPa at the lateral position and the minimum was 78 MPa at the posterior position. The residual stress in the bone axial direction varies around the circumferential region. In addition, the bone axial distributions of residual stresses were different in the proximal, middle, and distal sections of the individual femur. Furthermore, it was confirmed that residual stress in the bone tissue was released by the cutting out of the specimen. The residual stresses in bone tissue could be measured by this method. The results show that residual stress in the bone axial direction at the cortical surface in bovine femoral diaphysis is tensile and varies around the circumferential

  18. 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...

  19. Restoration of the endodontically treated posterior tooth

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    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.

  20. 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.)

  1. Posterior Predictive Model Checking in Bayesian Networks

    Science.gov (United States)

    Crawford, Aaron

    2014-01-01

    This simulation study compared the utility of various discrepancy measures within a posterior predictive model checking (PPMC) framework for detecting different types of data-model misfit in multidimensional Bayesian network (BN) models. The investigated conditions were motivated by an applied research program utilizing an operational complex…

  2. [Posterior longitudinal ligament ossification: case report].

    Science.gov (United States)

    Tella, Oswaldo Inácio de; Herculano, Marco Antonio; Paiva Neto, Manoel Antonio; Faedo Neto, Atílio; Crosera, João Francisco

    2006-03-01

    Posterior longitudinal ligament ossification of cervical spine is a rare condition among caucasians. A 42 years old japanese patient with progressive walking difficulty was diagnosed with this pathology by CT scan and MRI and treated surgically by an anterior approach with arthrodesis. Pathophysiology, racial prevalence, clinical picture, radiological characteristics and surgical approaches options are revised.

  3. Poor receptive joint attention skills are associated with atypical gray matter asymmetry in the posterior superior temporal gyrus of chimpanzees (Pan troglodytes)

    DEFF Research Database (Denmark)

    Hopkins, William D; Misiura, Maria; Reamer, Lisa A;

    2014-01-01

    Clinical and experimental data have implicated the posterior superior temporal gyrus as an important cortical region in the processing of socially relevant stimuli such as gaze following, eye direction, and head orientation. Gaze following and responding to different socio-communicative signals...... and behavioral data on receptive joint attention (RJA) was obtained from a sample of 191 chimpanzees. We found that chimpanzees that performed poorly on the RJA task had less GM in the right compared to left hemisphere in the posterior but not anterior superior temporal gyrus. We further found that middle...

  4. Bilateral Visual Loss as Presenting Symptom of Posterior Reversible Encephalopathy Syndrome in a Patient with HIV/Tuberculosis Coinfection: A Case Report

    Directory of Open Access Journals (Sweden)

    S. Guerriero

    2012-01-01

    Full Text Available Posterior reversible encephalopathy syndrome (PRES is a neurotoxic state accompanied by a unique brain imaging pattern. This cliniconeuroradiological entity usually presents with visual disturbances (cortical blindness, homonymous hemianopia, visual neglect, and blurred vision along with neurotoxic manifestations. Only a few cases of PRES have previously been reported in patients with advanced HIV disease. The authors describe a case of posterior reversible encephalopathy syndrome (PRES in a patient with advanced HIV/TBC infection who developed a neurotoxic state following TB and ART therapy initiation. They present a comprehensive review of the literature and discuss the pathogenetic hypotheses.

  5. Slowly progressive anarthria with late anterior opercular syndrome: a variant form of frontal cortical atrophy syndromes.

    Science.gov (United States)

    Broussolle, E; Bakchine, S; Tommasi, M; Laurent, B; Bazin, B; Cinotti, L; Cohen, L; Chazot, G

    1996-12-01

    We describe eight patients with slowly progressive speech production deficit combining speech apraxia, dysarthria, dysprosody and orofacial apraxia, and initially no other deficit in other language and non-language neuropsychological domains. Long-term follow-up (6-10 years) in 4 cases showed an evolution to muteness, bilateral suprabulbar paresis with automatic-voluntary dissociation and frontal lobe cognitive slowing without generalised intellectual deterioration. Most disabled patients presented with an anterior opercular syndrome (Foix-Chavany-Marie syndrome), and pyramidal or extrapyramidal signs. CT and MRI findings disclosed asymmetric (left > right) progressive cortical atrophy of the frontal lobes predominating in the posterior inferior frontal region, notably the operculum. SPECT and PET revealed a decreased cerebral blood flow and metabolism, prominent in the left posterior-inferior frontal gyrus and premotor cortex, extending bilaterally in the most advanced cases. Pathological study of two cases showed non-specific neuronal loss, gliosis, and spongiosis of superficial cortical layers, mainly confined to the frontal lobes, with no significant abnormalities in the basal ganglia, thalamus, cerebellum, brain stem (except severe neuronal loss in the substantia nigra in one case), and spinal cord. We propose to call this peculiar syndrome Slowly Progressive Anarthria (SPA), based on its specific clinical presentation, and its metabolic and pathological correlates. SPA represents another clinical expression of focal cortical degeneration syndromes, that may overlap with other similar syndromes, specially primary progressive aphasia and the various frontal lobe dementias.

  6. Techniques of the tympanomastoidectomy with reconstruction of the posterior bone wall of the external auditory canal

    Directory of Open Access Journals (Sweden)

    Dankuc Dragan

    2015-01-01

    Full Text Available A combined tympanoplasty method, the mobile-bridge tympanoplasty, has been applied at the Clinic for Ear, Nose and Throat Diseases in Novi Sad since 1998. Mobile-bridge tympanoplasty is performed at our Clinic by applying Feldmann’s procedure utilizing a microsurgical oscillating saw. It is a combination of closed and open techniques for surgical treatment of middle ear diseases. In addition to this technique, a method for reconstruction of the posterior bone wall of the external auditory canal was introduced. This procedure is applied in cases of damage or impairment of the bony ear canal wall using mastoid cortical temporal bone graft or modeled cartilage of the concha. Maintenance of general anatomical relations in the middle ear enables good ventilation of pneumatic spaces of the middle ear and Eustachian tube permeability, thus providing good conditions for ossicular chain reconstruction. The incidence of recurrent cholesteatoma in combined mobile-bridge tympanoplasty and tympanoplasty with reconstruction of the posterior bone wall was 6% in total. The incidence values for the recurrent cholesteatoma in closed tympanoplasty and in cases of open techniques were 10%. Mobile-bridge tympanoplasty and reconstruction of the posterior bone wall of external auditory canal are methods of choice in surgical treatment of middle ear cholesteatoma that progressed to the attic space, sinus tympani and facial recess.

  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. 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

  10. Primary Posterior Chamber Intraocular Lens Implantation in Traumatic Cataract With Posterior Capsule Breaks

    Institute of Scientific and Technical Information of China (English)

    YupingZou; WenhuiYang

    1995-01-01

    Background:In patients with incomplete posterior capsule support,posterior chamber intraocular lenses(PC-IOLs)were implanted with both haptics transs-cleral fixation.This causes more damage to the eye and may result in more com-plications,In patients with small posterior breaks,non-fixation or single haptic fixation may be adequate.Methods:Thiry-two consecutive patients of traumatic cataract with posterior capsule breaks caused by penetrating eye trauma were retospected.Posterior chamber intraocular lenses were implanted in all these patients with three tech-niques,ie,without fixation,with single haptic fixation and with both haptics fixation .The selection of the technique was based on the position and size of the posterior capsule.The follow-up period was 21days to 28months(mean,15.2months).Results:Intra-operative problems included ciliary body bleeding(Two patents,6.25%)and enlargement of posterior capsule breaks(2patients,6.25).Postoperative visual acuity was0.5or better(Corrected)in28case(87.5%)and 0.1-0.4in four patients(12.5%),Postoperative complications included hyphema(6eyes,18.8%),transient intraocular pressure elevation(6eyes,18.8%),transient hypotention(7eyes,21.8%).Postoperative IOL position were good except one case of IOL tilt.No pupillary capture or endophthalmitis was found.Conclusions:Not all PC-IOLs have to be fixed by two haptics.In patients with small posterior capsule breaks,PC-IOLmay not be fixed or fixed by only one haptics.Eye Science1995;11:140-142.

  11. Acute hepatic encephalopathy with diffuse cortical lesions

    Energy Technology Data Exchange (ETDEWEB)

    Arnold, S.M.; Spreer, J.; Schumacher, M. [Section of Neuroradiology, Univ. of Freiburg (Germany); Els, T. [Dept. of Neurology, University of Freiburg (Germany)

    2001-07-01

    Acute hepatic encephalopathy is a poorly defined syndrome of heterogeneous aetiology. We report a 49-year-old woman with alcoholic cirrhosis and hereditary haemorrhagic telangiectasia who developed acute hepatic coma induced by severe gastrointestinal bleeding. Laboratory analysis revealed excessively elevated blood ammonia. MRI showed lesions compatible with chronic hepatic encephalopathy and widespread cortical signal change sparing the perirolandic and occipital cortex. The cortical lesions resembled those of hypoxic brain damage and were interpreted as acute toxic cortical laminar necrosis. (orig.)

  12. 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.

  13. Optimal Feedback Communication via Posterior Matching

    CERN Document Server

    Shayevitz, Ofer

    2009-01-01

    In this paper we introduce a fundamental principle for optimal communication over general memoryless channels in the presence of noiseless feedback, termed \\textit{posterior matching}. Using this principle, we devise a (simple, sequential) generic feedback transmission scheme suitable for a large class of memoryless channels and input distributions, achieving any rate below the corresponding mutual information. This provides a unified framework for optimal feedback communication in which the Horstein scheme (BSC) and the Schalkwijk-Kailath scheme (AWGN channel) are special cases. Thus, as a corollary, we prove that the Horstein scheme indeed attains the BSC capacity, settling a longstanding conjecture. We further provide closed form expressions for the error probability of the scheme over a range of rates, and derive the achievable rates in a mismatch setting where the scheme is designed according to the wrong channel model. Finally, several illustrative examples of the posterior matching scheme for specific ...

  14. 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.

  15. SLEEP AND OLFACTORY CORTICAL PLASTICITY

    Directory of Open Access Journals (Sweden)

    Dylan eBarnes

    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.

  16. 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...

  17. 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.

  18. 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

  19. Restoration of the endodontically treated posterior tooth

    OpenAIRE

    Andrea Polesel

    2014-01-01

    Objectives: To analyse the key factors of the restoration in the posterior endodontically treated teeth, through a literature review and clinical cases presentation. To focus on the clinical advantages of the adhesive indirect restorations, describing the basic principles for long-term success. Materials and methods: The biomechanical changes due to the root canal therapy and the degree of healthy dental tissue lost because of pathology and iatrogenic factors are the critical points leadin...

  20. CT in thrombosed dilated posterior epidural vein

    Energy Technology Data Exchange (ETDEWEB)

    Bammatter, S.; Schnyder, P.; Preux, J. de

    1987-05-01

    The authors report a case of thrombosis of the distal end of an enlarged right posterior epidural vein. The patient had a markedly narrow lumbar canal due to L5 spondylolisthesis. The dilated vein and the thrombosis were displayed by computed tomography but remained unrecognized until surgery. Pathogenesis of this condition is discussed. A review of the English, French and German literature revealed no prior radiological reports of a similar condition.

  1. 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 co...... 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....

  2. 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.

  3. 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.

  4. 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.

  5. New England Medical Center Posterior Circulation registry.

    Science.gov (United States)

    Caplan, Louis R; Wityk, Robert J; Glass, Thomas A; Tapia, Jorge; Pazdera, Ladislav; Chang, Hui-Meng; Teal, Phillip; Dashe, John F; Chaves, Claudia J; Breen, Joan C; Vemmos, Kostas; Amarenco, Pierre; Tettenborn, Barbara; Leary, Megan; Estol, Conrad; Dewitt, L Dana; Pessin, Michael S

    2004-09-01

    Among 407 New England Medical Center Posterior Circulation registry patients, 59% had strokes without transient ischemic attacks (TIAs), 24% had TIAs then strokes, and 16% had only TIAs. Embolism was the commonest stroke mechanism (40% of patients including 24% cardiac origin, 14% intraarterial, 2% cardiac and arterial sources). In 32% large artery occlusive lesions caused hemodynamic brain ischemia. Infarcts most often included the distal posterior circulation territory (rostral brainstem, superior cerebellum and occipital and temporal lobes); the proximal (medulla and posterior inferior cerebellum) and middle (pons and anterior inferior cerebellum) territories were equally involved. Severe occlusive lesions (>50% stenosis) involved more than one large artery in 148 patients; 134 had one artery site involved unilaterally or bilaterally. The commonest occlusive sites were: extracranial vertebral artery (52 patients, 15 bilateral) intracranial vertebral artery (40 patients, 12 bilateral), basilar artery (46 patients). Intraarterial embolism was the commonest mechanism of brain infarction in patients with vertebral artery occlusive disease. Thirty-day mortality was 3.6%. Embolic mechanism, distal territory location, and basilar artery occlusive disease carried the poorest prognosis. The best outcome was in patients who had multiple arterial occlusive sites; they had position-sensitive TIAs during months to years.

  6. Detection of cortical activities on eye movement using functional magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Yoshida, Masaki; Kawai, Kazushige; Kitahara, Kenji [Jikei Univ., Tokyo (Japan). School of Medicine; Soulie, D.; Cordoliani, Y.S.; Iba-Zizen, M.T.; Cabanis, E.A.

    1997-11-01

    Cortical activity during eye movement was examined with functional magnetic resonance imaging. Horizontal saccadic eye movements and smooth pursuit eye movements were elicited in normal subjects. Activity in the frontal eye field was found during both saccadic and smooth pursuit eye movements at the posterior margin of the middle frontal gyrus and in parts of the precentral sulcus and precentral gyrus bordering the middle frontal gyrus (Brodmann`s areas 8, 6, and 9). In addition, activity in the parietal eye field was found in the deep, upper margin of the angular gyrus and of the supramarginal gyrus (Brodmann`s areas 39 and 40) during saccadic eye movement. Activity of V5 was found at the intersection of the ascending limb of the inferior temporal sulcus and the lateral occipital sulcus during smooth pursuit eye movement. Our results suggest that functional magnetic resonance imaging is useful for detecting cortical activity during eye movement. (author)

  7. Transient cortical blindness following vertebral angiography in a young adult with cerebellar haemangioblastoma

    Energy Technology Data Exchange (ETDEWEB)

    Till, Viktor; Stojanovic, Sanja; Avramov, Predrag [Clinical Centre of Vojvodina, Centre of Radiology, Novi Sad (RS); Koprivsek, Katarina [Institute of Oncology, Diagnostic Imaging Department, Sremska Kamenica (RS); Vulekovic, Petar [Clinical Centre of Vojvodina, Neurosurgery Clinic, Novi Sad (RS)

    2009-11-15

    Transient cortical blindness is reported to occur in 0.3% to 1% of cerebral angiography procedures. It develops within minutes of contrast medium injection and lasts for up to several days. We report a long episode of transient cortical blindness in a 17-year-old boy with cerebellar haemangioblastoma, which started during the preoperative vertebral angiography and lasted for 5 days. CT performed 2 days after the sudden onset of bilateral visual loss showed multiple asymmetrical lesions within the brain parenchyma in the distribution of the posterior cerebral circulation. Even though the patient's vision was completely restored 5 days after angiography, repeat MRI performed 2 months after angiography showed improvement but with residual lesions in the thalami, cerebellum and occipital lobe. (orig.)

  8. The influence of lexical statistics on temporal lobe cortical dynamics during spoken word listening

    Science.gov (United States)

    Cibelli, Emily S.; Leonard, Matthew K.; Johnson, Keith; Chang, Edward F.

    2015-01-01

    Neural representations of words are thought to have a complex spatio-temporal cortical basis. It has been suggested that spoken word recognition is not a process of feed-forward computations from phonetic to lexical forms, but rather involves the online integration of bottom-up input with stored lexical knowledge. Using direct neural recordings from the temporal lobe, we examined cortical responses to words and pseudowords. We found that neural populations were not only sensitive to lexical status (real vs. pseudo), but also to cohort size (number of words matching the phonetic input at each time point) and cohort frequency (lexical frequency of those words). These lexical variables modulated neural activity from the posterior to anterior temporal lobe, and also dynamically as the stimuli unfolded on a millisecond time scale. Our findings indicate that word recognition is not purely modular, but relies on rapid and online integration of multiple sources of lexical knowledge. PMID:26072003

  9. Transient cortical blindness following vertebral angiography in a young adult with cerebellar haemangioblastoma.

    Science.gov (United States)

    Till, Viktor; Koprivsek, Katarina; Stojanovic, Sanja; Avramov, Predrag; Vulekovic, Petar

    2009-11-01

    Transient cortical blindness is reported to occur in 0.3% to 1% of cerebral angiography procedures. It develops within minutes of contrast medium injection and lasts for up to several days. We report a long episode of transient cortical blindness in a 17-year-old boy with cerebellar haemangioblastoma, which started during the preoperative vertebral angiography and lasted for 5 days. CT performed 2 days after the sudden onset of bilateral visual loss showed multiple asymmetrical lesions within the brain parenchyma in the distribution of the posterior cerebral circulation. Even though the patient's vision was completely restored 5 days after angiography, repeat MRI performed 2 months after angiography showed improvement but with residual lesions in the thalami, cerebellum and occipital lobe.

  10. Drosophila Mon2 couples Oskar-induced endocytosis with actin remodeling for cortical anchorage of the germ plasm.

    Science.gov (United States)

    Tanaka, Tsubasa; Kato, Yasuko; Matsuda, Kazuki; Hanyu-Nakamura, Kazuko; Nakamura, Akira

    2011-06-01

    Drosophila pole (germ) plasm contains germline and abdominal determinants. Its assembly begins with the localization and translation of oskar (osk) RNA at the oocyte posterior, to which the pole plasm must be restricted for proper embryonic development. Osk stimulates endocytosis, which in turn promotes actin remodeling to form long F-actin projections at the oocyte posterior pole. Although the endocytosis-coupled actin remodeling appears to be crucial for the pole plasm anchoring, the mechanism linking Osk-induced endocytic activity and actin remodeling is unknown. Here, we report that a Golgi-endosomal protein, Mon2, acts downstream of Osk to remodel cortical actin and to anchor the pole plasm. Mon2 interacts with two actin nucleators known to be involved in osk RNA localization in the oocyte, Cappuccino (Capu) and Spire (Spir), and promotes the accumulation of the small GTPase Rho1 at the oocyte posterior. We also found that these actin regulators are required for Osk-dependent formation of long F-actin projections and cortical anchoring of pole plasm components. We propose that, in response to the Osk-mediated endocytic activation, vesicle-localized Mon2 acts as a scaffold that instructs the actin-remodeling complex to form long F-actin projections. This Mon2-mediated coupling event is crucial to restrict the pole plasm to the oocyte posterior cortex.

  11. Differential representation of arm movement direction in relation to cortical anatomy and function

    Science.gov (United States)

    Ball, Tonio; Schulze-Bonhage, Andreas; Aertsen, Ad; Mehring, Carsten

    2009-02-01

    Information about arm movement direction in neuronal activity of the cerebral cortex can be used for movement control mediated by a brain-machine interface (BMI). Here we provide a topographic analysis of the information related to arm movement direction that can be extracted from single trials of electrocorticographic (ECoG) signals recorded from the human frontal and parietal cortex based on a precise assignment of ECoG recording channels to the subjects' individual cortical anatomy and function. To this aim, each electrode contact was identified on structural MRI scans acquired while the electrodes were implanted and was thus related to the brain anatomy of each patient. Cortical function was assessed by direct cortical electrical stimulation. We show that activity from the primary motor cortex, in particular from the region showing hand and arm motor responses upon electrical stimulation, carries most directional information. The premotor, posterior parietal and lateral prefrontal cortex contributed gradually less, but still significant information. This gradient was observed for decoding from movement-related potentials, and from spectral amplitude modulations in low frequencies and in the high gamma band. Our findings thus demonstrate a close topographic correlation between cortical functional anatomy and direction-related information in humans that might be used for brain-machine interfacing.

  12. Reversible Cortical Blindness as a Prominent Manifestation of Cerebral Embolism due to Infective Endocarditis

    Directory of Open Access Journals (Sweden)

    Georgios P. Kranidiotis

    2010-01-01

    Full Text Available Introduction. Infective endocarditis in the left heart may be complicated by stroke, due to embolisation from infectious valvular vegetations. Infarction of both occipital lobes, which are supplied by the posterior cerebral arteries, is infrequent, and is the cause of cortical blindness from lesion of the visual cortex. Cortical blindness is characterized by intact pupillary reflexes, a normal fundoscopy, and, rarely, denial of visual loss. Case Presentation. We report the case of a 58-year-old woman, recipient of a mechanical aortic valve, who presented with fever, multiple organ dysfunction, and cortical blindness. Transesophageal echocardiography and blood cultures confirmed the diagnosis of infective endocarditis caused by methicillin-sensitive Staphylococcus aureus. Computed tomography of the brain without contrast revealed the presence of infarctions in both occipital lobes. It is noteworthy that the visual loss resolved after treatment of endocarditis. Conclusions. A stroke occurring in a patient presenting with fever and a history of valvular heart disease strongly suggests the presence of infective endocarditis. Bilateral thromboembolic infarcts of the occipital lobes cause cortical blindness, that can resolve after treatment of endocarditis.

  13. Reversible Cortical Blindness as a Prominent Manifestation of Cerebral Embolism due to Infective Endocarditis.

    Science.gov (United States)

    Kranidiotis, Georgios P; Gougoutsi, Alexandra N; Retsas, Theodoros A; Anastasiou-Nana, Maria I

    2010-01-01

    Introduction. Infective endocarditis in the left heart may be complicated by stroke, due to embolisation from infectious valvular vegetations. Infarction of both occipital lobes, which are supplied by the posterior cerebral arteries, is infrequent, and is the cause of cortical blindness from lesion of the visual cortex. Cortical blindness is characterized by intact pupillary reflexes, a normal fundoscopy, and, rarely, denial of visual loss. Case Presentation. We report the case of a 58-year-old woman, recipient of a mechanical aortic valve, who presented with fever, multiple organ dysfunction, and cortical blindness. Transesophageal echocardiography and blood cultures confirmed the diagnosis of infective endocarditis caused by methicillin-sensitive Staphylococcus aureus. Computed tomography of the brain without contrast revealed the presence of infarctions in both occipital lobes. It is noteworthy that the visual loss resolved after treatment of endocarditis. Conclusions. A stroke occurring in a patient presenting with fever and a history of valvular heart disease strongly suggests the presence of infective endocarditis. Bilateral thromboembolic infarcts of the occipital lobes cause cortical blindness, that can resolve after treatment of endocarditis.

  14. The tumor suppressor gene Trp53 protects the mouse lens against posterior subcapsular cataracts and the BMP receptor Acvr1 acts as a tumor suppressor in the lens

    Directory of Open Access Journals (Sweden)

    Luke A. Wiley

    2011-07-01

    We previously found that lenses lacking the Acvr1 gene, which encodes a bone morphogenetic protein (BMP receptor, had abnormal proliferation and cell death in epithelial and cortical fiber cells. We tested whether the tumor suppressor protein p53 (encoded by Trp53 affected this phenotype. Acvr1 conditional knockout (Acvr1CKO mouse fiber cells had increased numbers of nuclei that stained for p53 phosphorylated on serine 15, an indicator of p53 stabilization and activation. Deletion of Trp53 rescued the Acvr1CKO cell death phenotype in embryos and reduced Acvr1-dependent apoptosis in postnatal lenses. However, deletion of Trp53 alone increased the number of fiber cells that failed to withdraw from the cell cycle. Trp53CKO and Acvr1;Trp53DCKO (double conditional knockout, but not Acvr1CKO, lenses developed abnormal collections of cells at the posterior of the lens that resembled posterior subcapsular cataracts. Cells from human posterior subcapsular cataracts had morphological and molecular characteristics similar to the cells at the posterior of mouse lenses lacking Trp53. In Trp53CKO lenses, cells in the posterior plaques did not proliferate but, in Acvr1;Trp53DCKO lenses, many cells in the posterior plaques continued to proliferate, eventually forming vascularized tumor-like masses at the posterior of the lens. We conclude that p53 protects the lens against posterior subcapsular cataract formation by suppressing the proliferation of fiber cells and promoting the death of any fiber cells that enter the cell cycle. Acvr1 acts as a tumor suppressor in the lens. Enhancing p53 function in the lens could contribute to the prevention of steroid- and radiation-induced posterior subcapsular cataracts.

  15. Cortical blindness following spinal surgery: very rare cause of perioperative vision loss.

    Science.gov (United States)

    Goni, Vijay; Tripathy, Sujit Kumar; Goyal, Tarun; Tamuk, Tajir; Panda, Bijnya Birajita; Bk, Shashidhar

    2012-12-01

    A 38-year-old man was operated with posterior spinal decompression and pedicle screw instrumentation for his L2 fracture with incomplete neurological deficit. In the recovery, he complained of blindness in both eyes after twelve hours. Computed tomographic scan and magnetic resonance angiography revealed bilateral occipital lobe infarcts. He remained permanently blind even after three years follow-up. Though rare, perioperative vision loss is a potential complication following spine surgery in prone position. We report a rare occurrence of cortical blindness following lumbar spine surgery.

  16. Coronary artery disease affects cortical circuitry associated with brain-heart integration during volitional exercise.

    Science.gov (United States)

    Norton, Katelyn N; Badrov, Mark B; Barron, Carly C; Suskin, Neville; Heinecke, Armin; Shoemaker, J Kevin

    2015-08-01

    This study tested the hypothesis that coronary artery disease (CAD) alters the cortical circuitry associated with exercise. Observations of changes in heart rate (HR) and in cortical blood oxygenation level-dependent (BOLD) images were made in 23 control subjects [control; 8 women; 63 ± 11 yr; mean arterial pressure (MAP): 90 ± 9 mmHg] (mean ± SD) and 17 similarly aged CAD patients (4 women; 59 ± 9 yr; MAP: 87 ± 10 mmHg). Four repeated bouts each of 30%, 40%, and 50% of maximal voluntary contraction (MVC) force (LAB session), and seven repeated bouts of isometric handgrip (IHG) at 40% MVC force (fMRI session), were performed, with each contraction lasting 20 s and separated by 40 s of rest. There was a main effect of group (P = 0.03) on HR responses across all IHG intensities. Compared with control, CAD demonstrated less task-dependent deactivation in the posterior cingulate cortex and medial prefrontal cortex, and reduced activation in the right anterior insula, bilateral precentral cortex, and occipital lobe (P < 0.05). When correlated with HR, CAD demonstrated reduced activation in the bilateral insula and posterior cingulate cortex, and reduced deactivation in the dorsal anterior cingulate cortex, and bilateral precentral cortex (P < 0.05). The increased variability in expected autonomic regions and decrease in total cortical activation in response to the IHG task are associated with a diminished HR response to volitional effort in CAD. Therefore, relative to similarly aged and healthy individuals, CAD impairs the heart rate response and modifies the cortical patterns associated with cardiovascular control during IHG.

  17. Mapping the cortical representation of speech sounds in a syllable repetition task.

    Science.gov (United States)

    Markiewicz, Christopher J; Bohland, Jason W

    2016-11-01

    Speech repetition relies on a series of distributed cortical representations and functional pathways. A speaker must map auditory representations of incoming sounds onto learned speech items, maintain an accurate representation of those items in short-term memory, interface that representation with the motor output system, and fluently articulate the target sequence. A "dorsal stream" consisting of posterior temporal, inferior parietal and premotor regions is thought to mediate auditory-motor representations and transformations, but the nature and activation of these representations for different portions of speech repetition tasks remains unclear. Here we mapped the correlates of phonetic and/or phonological information related to the specific phonemes and syllables that were heard, remembered, and produced using a series of cortical searchlight multi-voxel pattern analyses trained on estimates of BOLD responses from individual trials. Based on responses linked to input events (auditory syllable presentation), predictive vowel-level information was found in the left inferior frontal sulcus, while syllable prediction revealed significant clusters in the left ventral premotor cortex and central sulcus and the left mid superior temporal sulcus. Responses linked to output events (the GO signal cueing overt production) revealed strong clusters of vowel-related information bilaterally in the mid to posterior superior temporal sulcus. For the prediction of onset and coda consonants, input-linked responses yielded distributed clusters in the superior temporal cortices, which were further informative for classifiers trained on output-linked responses. Output-linked responses in the Rolandic cortex made strong predictions for the syllables and consonants produced, but their predictive power was reduced for vowels. The results of this study provide a systematic survey of how cortical response patterns covary with the identity of speech sounds, which will help to constrain

  18. Talar Osteochondroma Fracture Presenting as Posterior Ankle Impingement.

    Science.gov (United States)

    Ercin, Ersin; Bilgili, Mustafa Gokhan; Gamsizkan, Mehmet; Avsar, Serdar

    2016-05-01

    Osteochondromas are the most common benign bone tumors. They are usually asymptomatic and found incidentally. When symptomatic, the symptoms are usually due to its location and size. Fracture of an osteochondroma presenting as posterior ankle impingement is a rare condition. We describe a 22-year-old man with solitary exostosis who presented with a posterior ankle mass and posterior ankle impingement with 2 years of follow-up. Surgical intervention was the treatment of choice in this patient, and histologic examination revealed a benign osteochondroma. Osteochondromas found in the posterior aspect of the talus can be complicated by fracture due to persistent motion of the ankle. Talar osteochondroma should be included in the differential diagnosis of posterior ankle impingement causes. Posterior talar osteochondromas, especially when a stalk is present, should be treated surgically before it is more complicated by a fracture and posterior ankle impingement.

  19. SINDROME DE COLAPSO DE MORDIDA POSTERIOR

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    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.

  20. MRI of the fetal posterior fossa

    Energy Technology Data Exchange (ETDEWEB)

    Adamsbaum, Catherine; Andre, Christine; Merzoug, Valerie; Ferey, Solene [St Vincent de Paul Hospital, Department of Radiology, Paris Cedex 14 (France); Moutard, Marie Laure [St Vincent de Paul Hospital, Department of Neuropaediatrics, Paris (France); Quere, Marie Pierre [CHU, Department of Radiology, Nantes (France); Lewin, Fanny [St Vincent de Paul Hospital, Maternity Department, Paris (France); Fallet-Bianco, Catherine [Ste Anne Hospital, Department of Neuropathology, Paris (France)

    2005-02-01

    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.)

  1. Subarachnoid hemorrhage due to ruptured intracranial aneurysm following posterior reversible encephalopathy syndrome

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    Takamasa Nanba

    2016-01-01

    Full Text Available Although posterior reversible encephalopathy syndrome (PRES is rarely associated with subarachnoid hemorrhage, to our knowledge, rupture of a concomitant cerebral aneurysm following PRES has not been reported. We describe a patient with atypical PRES involving the brainstem, thalamus, and periventricular white matter without cortical or subcortical edema of the parietooccipital lobe on magnetic resonance imaging, with rupture of a concomitant cerebral aneurysm. Preexisting extremely high blood pressure may trigger atypical PRES, and failure to lower blood pressure may lead to a concomitant aneurysm rupture. In the future treatment of hypertensive urgency with a recurrence of symptoms and mean arterial blood pressure >150 mmHg, it is advisable to immediately hospitalize the patient for aggressive blood pressure management, especially if PRES is suspected based on clinical and radiological features.

  2. 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...

  3. A Short History of Posterior Dynamic Stabilization

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    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.

  4. A isometricidade do ligamento cruzado posterior

    OpenAIRE

    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.

  5. Luxación esternoclavicular posterior

    OpenAIRE

    Ojeda Gómez, Juan Sebastián; Morales Cifuentes, Laura Cristina; Rojas Arbeláez, Luis Felipe

    2016-01-01

    Paciente masculino de 24 años, ingresa a urgencias por trauma contundente en clavícula derecha durante accidente de tránsito. Presenta dolor en articulación esternoclavicular que se exacerba con la movilización del hombro y disfagia. Al examen físico, leve depresión del extremo medial de la clavícula y limitación de los arcos de movimiento del hombro. Las imágenes confirmaron el diagnostico de LEC posterior. El paciente fue llevado a cirugía para reducción y cerclaje, sin complicaciones....

  6. Reversible Posterior Encephalopathy Syndrome Secondary to Sunitinib

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    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. Cortical atrophy patterns in multiple sclerosis are non-random and clinically relevant.

    Science.gov (United States)

    Steenwijk, Martijn D; Geurts, Jeroen J G; Daams, Marita; Tijms, Betty M; Wink, Alle Meije; Balk, Lisanne J; Tewarie, Prejaas K; Uitdehaag, Bernard M J; Barkhof, Frederik; Vrenken, Hugo; Pouwels, Petra J W

    2016-01-01

    Grey matter atrophy is common in multiple sclerosis. However, in contrast with other neurodegenerative diseases, it is unclear whether grey matter atrophy in multiple sclerosis is a diffuse 'global' process or develops, instead, according to distinct anatomical patterns. Using source-based morphometry we searched for anatomical patterns of co-varying cortical thickness and assessed their relationships with white matter pathology, physical disability and cognitive functioning. Magnetic resonance imaging was performed at 3 T in 208 patients with long-standing multiple sclerosis (141 females; age = 53.7 ± 9.6 years; disease duration = 20.2 ± 7.1 years) and 60 age- and sex-matched healthy controls. Spatial independent component analysis was performed on cortical thickness maps derived from 3D T1-weighted images across all subjects to identify co-varying patterns. The loadings, which reflect the presence of each cortical thickness pattern in a subject, were compared between patients with multiple sclerosis and healthy controls with generalized linear models. Stepwise linear regression analyses were used to assess whether white matter pathology was associated with these loadings and to identify the cortical thickness patterns that predict measures of physical and cognitive dysfunction. Ten cortical thickness patterns were identified, of which six had significantly lower loadings in patients with multiple sclerosis than in controls: the largest loading differences corresponded to the pattern predominantly involving the bilateral temporal pole and entorhinal cortex, and the pattern involving the bilateral posterior cingulate cortex. In patients with multiple sclerosis, overall white matter lesion load was negatively associated with the loadings of these two patterns. The final model for physical dysfunction as measured with Expanded Disability Status Scale score (adjusted R(2) = 0.297; P atrophy patterns relevant for multiple sclerosis were found. This suggests that

  8. Organisation of Xenopus oocyte and egg cortices.

    Science.gov (United States)

    Chang, P; Pérez-Mongiovi, D; Houliston, E

    1999-03-15

    The division of the Xenopus oocyte cortex into structurally and functionally distinct "animal" and "vegetal" regions during oogenesis provides the basis of the organisation of the early embryo. The vegetal region of the cortex accumulates specific maternal mRNAs that specify the development of the endoderm and mesoderm, as well as functionally-defined "determinants" of dorso-anterior development, and recognisable "germ plasm" determinants that segregate into primary germ cells. These localised elements on the vegetal cortex underlie both the primary animal-vegetal polarity of the egg and the organisation of the developing embryo. The animal cortex meanwhile becomes specialised for the events associated with fertilisation: sperm entry, calcium release into the cytoplasm, cortical granule exocytosis, and polarised cortical contraction. Cortical and subcortical reorganisations associated with meiotic maturation, fertilisation, cortical rotation, and the first mitotic cleavage divisions redistribute the vegetal cortical determinants, contributing to the specification of dorso-anterior axis and segregation of the germ line. In this article we consider what is known about the changing organisation of the oocyte and egg cortex in relation to the mechanisms of determinant localisation, anchorage, and redistribution, and show novel ultrastructural views of cortices isolated at different stages and processed by the rapid-freeze deep-etch method. Cortical organisation involves interactions between the different cytoskeletal filament systems and internal membranes. Associated proteins and cytoplasmic signals probably modulate these interactions in stage-specific ways, leaving much to be understood.

  9. Kashima's Posterior cordectomy using coablator our experience

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    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.

  10. Acute Spontaneous Posterior Fossa Subdural Hematoma

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    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.

  11. Posterior repair with perforated porcine dermal graft

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    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.

  12. Bayesian posterior distributions without Markov chains.

    Science.gov (United States)

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

    2012-03-01

    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 exposure to magnetic fields and the development of childhood cancer. Results from rejection sampling (odds ratio (OR) = 1.69, 95% posterior interval (PI): 0.57, 5.00) were similar to MCMC results (OR = 1.69, 95% PI: 0.58, 4.95) and approximations from data-augmentation priors (OR = 1.74, 95% PI: 0.60, 5.06). In example 2, the authors apply rejection sampling to a cohort study of 315 human immunodeficiency virus seroconverters (1984-1998) to assess the relation between viral load after infection and 5-year incidence of acquired immunodeficiency syndrome, adjusting for (continuous) age at seroconversion and race. In this more complex example, rejection sampling required a notably longer run time than MCMC sampling but remained feasible and again yielded similar results. The transparency of the proposed approach comes at a price of being less broadly applicable than MCMC.

  13. Microsurgical anatomy of the posterior fossa cisterns.

    Science.gov (United States)

    Matsuno, H; Rhoton, A L; Peace, D

    1988-07-01

    The microsurgical anatomy of the posterior fossa cisterns was examined in 15 cadavers using 3X to 40X magnification. Liliequist's membrane was found to split into two arachnoidal sheets as it spreads upward from the dorsum sellae: an upper sheet, called the diencephalic membrane, which attaches to the diencephalon at the posterior edge of the mamillary bodies, and a lower sheet, called the mesencephalic membrane, which attaches along the junction of the midbrain and pons. Several other arachnoidal membranes that separate the cisterns were identified. These include the anterior pontine membrane, which separates the prepontine and cerebellopontine cisterns; the lateral pontomesencephalic membrane, which separates the ambient and cerebellopontine cisterns; the medial pontomedullary membrane, which separates the premedullary and prepontine cisterns; and the lateral pontomedullary membrane, which separates the cerebellopontine and cerebellomedullary cisterns. The three cisterns in which the arachnoid trabeculae and membranes are the most dense and present the greatest obstacle at operation are the interpeduncular and quadrigeminal cisterns and the cisterna magna. Numerous arachnoid membranes were found to intersect the oculomotor nerves. The neural and vascular structures in each cistern are reviewed.

  14. Posterior fossa involvement in a recurrent gliosarcoma

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    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.

  15. Treatment of posterior Wall fractures of acetabulum

    Institute of Scientific and Technical Information of China (English)

    QI Xin; LIU Jian-guo; GONG Yu-bao; YANG Chen; LI Shu-qiang; FENG Wei

    2009-01-01

    Objective: To explore the treatment methods and outcome of posterior Wall fractures of the acetabulum.Methods: The data of 31 patients(25 males and 6females,aged 19-59 years,mean:40.5 years)with posterior wall fractures of the acetabulum hospitalized in our department from 2002 to 2006 were analyzed retrospectively in this study.The types of fractures,number of fragments,combined dislocations,and sciatic nerve function were documented before admission.All the fractures were treated with open reduction and internal fixation.Based on the fracture type and site,either screws alone or reconstructive plates were used.The Patients were immobilized for an average of 12 weeks before partial weight bearing was permitted.After follow-up for 12-70months(43.6months on average),modifled Merle d‘Aubigne score was adopted to evaluate the outcomes of the operations.Results: The percentages of the excellent,good,fair and poor results were 48.4%,41.9%,6.5%,and 3.3%,respectively.with a good to excellent rate of 90.2%.Idio-pathic sciatic nerve injury occurred in only one case.Conclusions: The sciatic nerve should be routinely exposed and protected during the surgery.The type of fixation should be based on the fracture type and site.Prolonged immobilization may be helpful in improving the final outcomes.

  16. Posterior Interosseous Nerve Syndrome from Thermal Injury

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    Vijay A. Singh

    2014-01-01

    Full Text Available Background. Due to anatomical proximity to bone, the radial nerve is the most frequently injured major nerve of the upper extremity, frequently secondary to fractures (Li et al. (2013. We describe an incidence when a branch of the radial nerve is injured as a result of a thermal injury. Observation. Radial nerve injury can occur anywhere along the anatomical course with varied etiologies, but commonly related to trauma. The most frequent site is in the proximal forearm involving the posterior interosseous branch. However, problems can occur at the junction of the middle and proximal thirds of the humerus and wrist radially. When the radial nerve is injured by a burn, a new rehabilitation dynamic arises. Not only does one agonize about the return of nerve function but also fret about the skin grafts that replaced the devitalized tissue housing that compartment. Discussion. Although posterior interosseous nerve syndrome has been described in the context of many different etiologies, it has not previously been discussed in relation to burn injuries. In this case, not only did the patient’s rehabilitation involve aggressive therapy for return of sensation and function of the arm, but also prevention of contracture normally seen in replacement of full thickness burns.

  17. 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.

  18. Anomalous posterior clinoid process and its clinical importance

    Directory of Open Access Journals (Sweden)

    Shipra Paul

    2007-09-01

    Full Text Available 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 and the main source of information are the research reports. The present osteological study describes anomalous posterior clinoid process, detected in two human skulls, during routine undergraduate medical teaching and also discusses its clinical importance. The posterior clinoid process anomalies may be responsible for the altered arrangement of the tentorium cerebelli which is attached to it. The internal carotid artery is often explored by the neuro-surgeon and any bony abnormalities in its vicinity, would result in a difficult situation, while performing clinoidectomy operations. Anomalous posterior clinoid process, may compress the internal carotid artery. The close position of the superior petrosal sinus and the internal carotid artery to the posterior clinoid process, makes it vulnerable to injuries and thus it is important for the neuro-surgeons performing clinoidectomy operations. The anatomy of the posterior clinoid process may be important for neuro surgeons and radiologists in day to day clinical practice.

  19. Anomalous posterior clinoid process and its clinical importance.

    Directory of Open Access Journals (Sweden)

    Shipra Paul

    2009-11-01

    Full Text Available 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 and the main source of information are the research reports. The present osteological study describes anomalous posterior clinoid process, detected in two human skulls, during routine undergraduate medical teaching and also discusses its clinical importance. The posterior clinoid process anomalies may be responsible for the altered arrangement of the tentorium cerebelli which is attached to it. The internal carotid artery is often explored by the neuro-surgeon and any bony abnormalities in its vicinity, would result in a difficult situation, while performing clinoidectomy operations. Anomalous posterior clinoid process, may compress the internal carotid artery. The close position of the superior petrosal sinus and the internal carotid artery to the posterior clinoid process, makes it vulnerable to injuries and thus it is important for the neuro-surgeons performing clinoidectomy operations. The anatomy of the posterior clinoid process may be important for neuro surgeons and radiologists in day to day clinical practice.

  20. Plasticity in the rat posterior auditory field following nucleus basalis stimulation.

    Science.gov (United States)

    Puckett, Amanda C; Pandya, Pritesh K; Moucha, Raluca; Dai, WeiWei; Kilgard, Michael P

    2007-07-01

    Classical conditioning paradigms have been shown to cause frequency-specific plasticity in both primary and secondary cortical areas. Previous research demonstrated that repeated pairing of nucleus basalis (NB) stimulation with a tone results in plasticity in primary auditory cortex (A1), mimicking the changes observed after classical conditioning. However, few studies have documented the effects of similar paradigms in secondary cortical areas. The purpose of this study was to quantify plasticity in the posterior auditory field (PAF) of the rat after NB stimulation paired with a high-frequency tone. NB-tone pairing increased the frequency selectivity of PAF sites activated by the paired tone. This frequency-specific receptive field size narrowing led to a reorganization of PAF such that responses to low- and mid-frequency tones were reduced by 40%. Plasticity in A1 was consistent with previous studies -- pairing a high-frequency tone with NB stimulation expanded the high-frequency region of the frequency map. Receptive field sizes did not change, but characteristic frequencies in A1 were shifted after NB-tone pairing. These results demonstrate that experience-dependent plasticity can take different forms in both A1 and secondary auditory cortex.

  1. Differential motor and prefrontal cerebello-cortical network development: Evidence from multimodal neuroimaging.

    Science.gov (United States)

    Bernard, Jessica A; Orr, Joseph M; Mittal, Vijay A

    2016-01-01

    While our understanding of cerebellar structural development through adolescence and young adulthood has expanded, we still lack knowledge of the developmental patterns of cerebellar networks during this critical portion of the lifespan. Volume in lateral posterior cerebellar regions associated with cognition and the prefrontal cortex develops more slowly, reaching their peak volume in adulthood, particularly as compared to motor Lobule V. We predicted that resting state functional connectivity of the lateral posterior regions would show a similar pattern of development during adolescence and young adulthood. That is, we expected to see changes over time in Crus I and Crus II connectivity with the cortex, but no changes in Lobule V connectivity. Additionally, we were interested in how structural connectivity changes in cerebello-thalamo-cortical white matter are related to changes in functional connectivity. A sample of 23 individuals between 12 and 21years old underwent neuroimaging scans at baseline and 12months later. Functional networks of Crus I and Crus II showed significant connectivity decreases over 12months, though there were no differences in Lobule V. Furthermore, these functional connectivity changes were correlated with increases in white matter structural integrity in the corresponding cerebello-thalamo-cortical white matter tract. We suggest that these functional network changes are due to both later pruning in the prefrontal cortex as well as further development of the white matter tracts linking these brain regions.

  2. Contrast-associated transient cortical blindness: three cases with MRI and electrophysiology findings.

    Science.gov (United States)

    Baguma, Marius; Younan, Nadia; London, Frédéric; Ossemann, Michel; Vandermeeren, Yves

    2016-09-26

    Transient cortical blindness (TCB) is a rare but striking complication following contrast agent injection. TCB might be secondary to a direct toxicity of the contrast agent, leading to an osmotic disruption of the blood-brain barrier (BBB), with a preferential involvement of the posterior circulation and occipital cortex. We report a series of three patients with contrast medium-associated TCB (intra-arterial injection of non-ionic contrast agent during diagnostic cerebral angiography for two of them and coronary angioplasty for the other one). In two patients, the magnetic resonance imaging (MRI) was unremarkable; in the other patient, typical MRI findings were observed, with FLAIR hyperintensities in the right occipital cortex and decreased apparent diffusions coefficient (ADC). Interestingly, this patient also presented posterior rhythmic epileptiform activities on electroencephalogram during the first 36 h. Visual evoked potentials (VEPs) showed normal retinal potential, but a massive destructuration of the later potentials of the cortical origin. To our knowledge, this is the first time that VEPs acquired during TCB are reported. We discuss these findings with respect to the pathophysiology of TCB.

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

    Science.gov (United States)

    Delli Pizzi, Stefano; Franciotti, Raffaella; Tartaro, Armando; Caulo, Massimo; Thomas, Astrid; Onofrj, Marco; Bonanni, Laura

    2014-01-01

    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.

  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. Patient with pontine warning syndrome and bilateral posterior internuclear ophthalmoplegia: case report

    Directory of Open Access Journals (Sweden)

    Su Li

    2010-06-01

    Full Text Available Abstract Background Capsular warning syndrome was first described in 1993, featured with repetitive episodes of motor and/or sensory dysfunction without cortical signs. Recently, it has been demonstrated that clinically typical capsular warning syndrome can be associated with pontine infarct and the term “pontine warning syndrome� was coined. Case Presentation A 54-year-old woman with a history of hypertension was seen with profound left-sided hemiplegia. She had had 3 episodes of left-sided weakness before complete hemiplegia. Her speech was slurred. Left central facial palsy and hemiglossoplegia were presented. Her left plantar response was extensor and bilateral posterior internuclear ophthalmoplegia was seen on neurologic examination. Biochemical tests revealed hyperglycemia and dyslipidemia on the next day. MRI demonstrated an acute right paramedian pontine infarct. The patient was commenced on oral clopidogrel, atorvastatin and acarbose. After 23 days of hospitalization, she was discharged with severe left hemiplegia. Conclusions 1 Pontine warning syndrome may be underestimated and understudied. 2 Posterior internuclear ophthalmoplegia is a rare clinical sign in cerebrovascular diseases, while it can help to locate a brainstem lesion rather than an internal capsular one. 3 Blood pressure lowing administration may be improper for patients with pontine warning syndrome.

  6. The posterior vermis of the cerebellum selectively inhibits 10-Hz sympathetic nerve discharge in anesthetized cats.

    Science.gov (United States)

    Barman, Susan M; Gebber, Gerard L

    2009-07-01

    We studied the changes in inferior cardiac sympathetic nerve discharge (SND) and mean arterial pressure (MAP) produced by aspiration or chemical inactivation (muscimol microinjection) of lobule IX (uvula) of the posterior vermis of the cerebellum in baroreceptor-denervated and baroreceptor-innervated cats anesthetized with urethane. Autospectral analysis was used to decompose SND into its frequency components. Special attention was paid to the question of whether the experimental procedures affected the rhythmic (10-Hz and cardiac-related) components of SND. Aspiration or chemical inactivation of lobule IX produced an approximately three-fold increase in the 10-Hz rhythmic component of SND (P cats. Total power (0- to 20-Hz band) was unchanged. Despite the absence of a change in total power in SND, there was a statistically significant increase in MAP. In baroreceptor-innervated cats, neither aspiration nor chemical inactivation of the uvula caused a significant change in cardiac-related or total power in SND or MAP. These results are the first to demonstrate a role of cerebellar cortical neurons of the posterior vermis in regulating the frequency composition of naturally occurring SND. Specifically, these neurons selectively inhibit the 10-Hz rhythm-generating network in baroreceptor-denervated, urethane-anesthetized cats. The functional implications of these findings are discussed.

  7. Superresolution improves MRI cortical segmentation with FACE

    DEFF Research Database (Denmark)

    Eskildsen, Simon Fristed; Manjón, José V.; Coupé, Pierrick

    Brain cortical surface extraction from MRI has applications for measurement of gray matter (GM) atrophy, functional mapping, source localization and preoperative neurosurgical planning. Accurate cortex segmentation requires high resolution morphological images and several methods for extracting...

  8. 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.

  9. Transient cortical blindness after coronary angiography.

    Science.gov (United States)

    Alp, B N; Bozbuğa, N; Tuncer, M A; Yakut, C

    2009-01-01

    Transient cortical blindness is rarely encountered after angiography of native coronary arteries or bypass grafts. This paper reports a case of transient cortical blindness that occurred 72 h after coronary angiography in a 56-year old patient. This was the patient's fourth exposure to contrast medium. Neurological examination demonstrated cortical blindness and the absence of any focal neurological deficit. A non-contrast-enhanced computed tomographic scan of the brain revealed bilateral contrast enhancement in the occipital lobes and no evidence of cerebral haemorrhage, and magnetic resonance imaging of the brain showed no pathology. Sight returned spontaneously within 4 days and his vision gradually improved. A search of the current literature for reported cases of transient cortical blindness suggested that this is a rarely encountered complication of coronary angiography.

  10. Reversible cortical blindness after lung transplantation.

    Science.gov (United States)

    Knower, Mark T; Pethke, Scott D; Valentine, Vincent G

    2003-06-01

    Cyclosporine (CYA) is a calcineurin inhibitor widely used in immunosuppressive regimens after organ transplantation. Several neurologic side effects are frequently associated with CYA use; however, reversible cortical blindness is a rare manifestation of CYA toxicity traditionally seen after liver and bone marrow transplantation. This report presents a case of reversible cortical blindness after lung transplantation, then details the risk factors and clinical course of 28 previously well-documented cases of CYA-induced cortical blindness after transplantation. Identification of known risk factors, clinical clues, and typical radiographic findings may aid in the diagnosis of CYA-induced cortical blindness, since reduction in CYA dose or cessation of CYA therapy usually permits resolution of the neurologic effects.

  11. Three-Dimensional Eye Position Signals Shape Both Peripersonal Space and Arm Movement Activity in the Medial Posterior Parietal Cortex.

    Directory of Open Access Journals (Sweden)

    Kostas eHadjidimitrakis

    2012-06-01

    Full Text Available Research conducted over the last decades has established that the medial part of posterior parietal cortex is crucial for controlling visually guided actions in human and non-human primates. Within this cortical sector there is area V6A, a crucial node of the parietofrontal network involved in arm movement control in both monkeys and humans. However, the encoding of action-in-depth by V6A cells had been not studied till recently. Recent neurophysiological studies show the existence in V6A neurons of signals related to the distance of targets from the eyes. These signals are integrated, often at the level of single cells, with information about the direction of gaze, thus encoding spatial location in 3D space. Moreover, 3D eye position signals seem to be further exploited at two additional levels of neural processing: a in determining whether targets are located in the peripersonal space or not, and b in shaping the spatial tuning of arm movement related activity towards reachable targets. These findings are in line with studies in putative homolog regions in humans and together point to a role of medial posterior parietal cortex in encoding both the vergence angle of the eyes and peripersonal space. Besides this role in spatial encoding also in depth, several findings demonstrate the involvement of this cortical sector in non-spatial processes.

  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. Cortical depth dependence of the diffusion anisotropy in the human cortical gray matter in vivo.

    Directory of Open Access Journals (Sweden)

    Trong-Kha Truong

    Full Text Available Diffusion tensor imaging (DTI is typically used to study white matter fiber pathways, but may also be valuable to assess the microstructure of cortical gray matter. Although cortical diffusion anisotropy has previously been observed in vivo, its cortical depth dependence has mostly been examined in high-resolution ex vivo studies. This study thus aims to investigate the cortical depth dependence of the diffusion anisotropy in the human cortex in vivo on a clinical 3 T scanner. Specifically, a novel multishot constant-density spiral DTI technique with inherent correction of motion-induced phase errors was used to achieve a high spatial resolution (0.625 × 0.625 × 3 mm and high spatial fidelity with no scan time penalty. The results show: (i a diffusion anisotropy in the cortical gray matter, with a primarily radial diffusion orientation, as observed in previous ex vivo and in vivo studies, and (ii a cortical depth dependence of the fractional anisotropy, with consistently higher values in the middle cortical lamina than in the deep and superficial cortical laminae, as observed in previous ex vivo studies. These results, which are consistent across subjects, demonstrate the feasibility of this technique for investigating the cortical depth dependence of the diffusion anisotropy in the human cortex in vivo.

  14. Cortical depth dependence of the diffusion anisotropy in the human cortical gray matter in vivo.

    Science.gov (United States)

    Truong, Trong-Kha; Guidon, Arnaud; Song, Allen W

    2014-01-01

    Diffusion tensor imaging (DTI) is typically used to study white matter fiber pathways, but may also be valuable to assess the microstructure of cortical gray matter. Although cortical diffusion anisotropy has previously been observed in vivo, its cortical depth dependence has mostly been examined in high-resolution ex vivo studies. This study thus aims to investigate the cortical depth dependence of the diffusion anisotropy in the human cortex in vivo on a clinical 3 T scanner. Specifically, a novel multishot constant-density spiral DTI technique with inherent correction of motion-induced phase errors was used to achieve a high spatial resolution (0.625 × 0.625 × 3 mm) and high spatial fidelity with no scan time penalty. The results show: (i) a diffusion anisotropy in the cortical gray matter, with a primarily radial diffusion orientation, as observed in previous ex vivo and in vivo studies, and (ii) a cortical depth dependence of the fractional anisotropy, with consistently higher values in the middle cortical lamina than in the deep and superficial cortical laminae, as observed in previous ex vivo studies. These results, which are consistent across subjects, demonstrate the feasibility of this technique for investigating the cortical depth dependence of the diffusion anisotropy in the human cortex in vivo.

  15. CLADA: cortical longitudinal atrophy detection algorithm.

    Science.gov (United States)

    Nakamura, Kunio; Fox, Robert; Fisher, Elizabeth

    2011-01-01

    Measurement of changes in brain cortical thickness is useful for the assessment of regional gray matter atrophy in neurodegenerative conditions. A new longitudinal method, called CLADA (cortical longitudinal atrophy detection algorithm), has been developed for the measurement of changes in cortical thickness in magnetic resonance images (MRI) acquired over time. CLADA creates a subject-specific cortical model which is longitudinally deformed to match images from individual time points. The algorithm was designed to work reliably for lower resolution images, such as the MRIs with 1×1×5 mm(3) voxels previously acquired for many clinical trials in multiple sclerosis (MS). CLADA was evaluated to determine reproducibility, accuracy, and sensitivity. Scan-rescan variability was 0.45% for images with 1mm(3) isotropic voxels and 0.77% for images with 1×1×5 mm(3) voxels. The mean absolute accuracy error was 0.43 mm, as determined by comparison of CLADA measurements to cortical thickness measured directly in post-mortem tissue. CLADA's sensitivity for correctly detecting at least 0.1mm change was 86% in a simulation study. A comparison to FreeSurfer showed good agreement (Pearson correlation=0.73 for global mean thickness). CLADA was also applied to MRIs acquired over 18 months in secondary progressive MS patients who were imaged at two different resolutions. Cortical thinning was detected in this group in both the lower and higher resolution images. CLADA detected a higher rate of cortical thinning in MS patients compared to healthy controls over 2 years. These results show that CLADA can be used for reliable measurement of cortical atrophy in longitudinal studies, even in lower resolution images.

  16. Cortical Neural Computation by Discrete Results Hypothesis

    Science.gov (United States)

    Castejon, Carlos; Nuñez, Angel

    2016-01-01

    One of the most challenging problems we face in neuroscience is to understand how the cortex performs computations. There is increasing evidence that the power of the cortical processing is produced by populations of neurons forming dynamic neuronal ensembles. Theoretical proposals and multineuronal experimental studies have revealed that ensembles of neurons can form emergent functional units. However, how these ensembles are implicated in cortical computations is still a mystery. Although cell ensembles have been associated with brain rhythms, the functional interaction remains largely unclear. It is still unknown how spatially distributed neuronal activity can be temporally integrated to contribute to cortical computations. A theoretical explanation integrating spatial and temporal aspects of cortical processing is still lacking. In this Hypothesis and Theory article, we propose a new functional theoretical framework to explain the computational roles of these ensembles in cortical processing. We suggest that complex neural computations underlying cortical processing could be temporally discrete and that sensory information would need to be quantized to be computed by the cerebral cortex. Accordingly, we propose that cortical processing is produced by the computation of discrete spatio-temporal functional units that we have called “Discrete Results” (Discrete Results Hypothesis). This hypothesis represents a novel functional mechanism by which information processing is computed in the cortex. Furthermore, we propose that precise dynamic sequences of “Discrete Results” is the mechanism used by the cortex to extract, code, memorize and transmit neural information. The novel “Discrete Results” concept has the ability to match the spatial and temporal aspects of cortical processing. We discuss the possible neural underpinnings of these functional computational units and describe the empirical evidence supporting our hypothesis. We propose that fast

  17. Cortical Source Localization of Infant Cognition

    OpenAIRE

    Reynolds, GD; Richards, JE

    2009-01-01

    Neuroimaging techniques such as positron emission topography (PET) and functional magnetic resonance imaging (fMRI) have been utilized with older children and adults to identify cortical sources of perceptual and cognitive processes. However, due to practical and ethical concerns, these techniques cannot be routinely applied to infant participants. An alternative to such neuroimaging techniques appropriate for use with infant participants is high-density EEG recording and cortical source loca...

  18. Atlantoaxial stabilization using multiaxial C-1 posterior arch screws.

    Science.gov (United States)

    Donnellan, Michael B; Sergides, Ioannis G; Sears, William R

    2008-12-01

    The authors present a novel technique of atlantoaxial fixation using multiaxial C-1 posterior arch screws. The technique involves the insertion of bilateral multiaxial C-1 posterior arch screws, which are connected by crosslinked rods to bilateral multiaxial C-2 pars screws. The clinical results are presented in 3 patients in whom anomalies of the vertebral arteries, C-1 lateral masses, and/or posterior arch of C-1 presented difficulty using existing fixation techniques with transarticular screws, C-1 lateral mass screws, or posterior wiring. The C-1 posterior arch screws achieved solid fixation and their insertion appeared to be technically less demanding than that of transarticular or C-1 lateral mass screws. This technique may reduce the risk of complications compared with existing techniques, especially in patients with anatomical variants of the vertebral artery, C-1 lateral masses, or C-1 posterior arch. This technique may prove to be an attractive fixation option in patients with normal anatomy.

  19. 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

  20. From oocyte to 16-cell stage: cytoplasmic and cortical reorganizations that pattern the ascidian embryo.

    Science.gov (United States)

    Sardet, Christian; Paix, Alexandre; Prodon, François; Dru, Philippe; Chenevert, Janet

    2007-07-01

    The dorsoventral and anteroposterior axes of the ascidian embryo are defined before first cleavage by means of a series of reorganizations that reposition cytoplasmic and cortical domains established during oogenesis. These domains situated in the periphery of the oocyte contain developmental determinants and a population of maternal postplasmic/PEM RNAs. One of these RNAs (macho-1) is a determinant for the muscle cells of the tadpole embryo. Oocytes acquire a primary animal-vegetal (a-v) axis during meiotic maturation, when a subcortical mitochondria-rich domain (myoplasm) and a domain rich in cortical endoplasmic reticulum (cER) and maternal postplasmic/PEM RNAs (cER-mRNA domain) become polarized and asymmetrically enriched in the vegetal hemisphere. Fertilization at metaphase of meiosis I initiates a series of dramatic cytoplasmic and cortical reorganizations of the zygote, which occur in two major phases. The first major phase depends on sperm entry which triggers a calcium wave leading in turn to an actomyosin-driven contraction wave. The contraction concentrates the cER-mRNA domain and myoplasm in and around a vegetal/contraction pole. The precise localization of the vegetal/contraction pole depends on both the a-v axis and the location of sperm entry and prefigures the future site of gastrulation and dorsal side of the embryo. The second major phase of reorganization occurs between meiosis completion and first cleavage. Sperm aster microtubules and then cortical microfilaments cause the cER-mRNA domain and myoplasm to reposition toward the posterior of the zygote. The location of the posterior pole depends on the localization of the sperm centrosome/aster attained during the first major phase of reorganization. Both cER-mRNA and myoplasm domains localized in the posterior region are partitioned equally between the first two blastomeres and then asymmetrically over the next two cleavages. At the eight-cell stage the cER-mRNA domain compacts and gives rise to

  1. Effects of Habitual Physical Activity and Fitness on Tibial Cortical Bone Mass, Structure and Mass Distribution in Pre-pubertal Boys and Girls: The Look Study.

    Science.gov (United States)

    Duckham, Rachel L; Rantalainen, Timo; Ducher, Gaele; Hill, Briony; Telford, Richard D; Telford, Rohan M; Daly, Robin M

    2016-07-01

    Targeted weight-bearing activities during the pre-pubertal years can improve cortical bone mass, structure and distribution, but less is known about the influence of habitual physical activity (PA) and fitness. This study examined the effects of contrasting habitual PA and fitness levels on cortical bone density, geometry and mass distribution in pre-pubertal children. Boys (n = 241) and girls (n = 245) aged 7-9 years had a pQCT scan to measure tibial mid-shaft total, cortical and medullary area, cortical thickness, density, polar strength strain index (SSIpolar) and the mass/density distribution through the bone cortex (radial distribution divided into endo-, mid- and pericortical regions) and around the centre of mass (polar distribution). Four contrasting PA and fitness groups (inactive-unfit, inactive-fit, active-unfit, active-fit) were generated based on daily step counts (pedometer, 7-days) and fitness levels (20-m shuttle test and vertical jump) for boys and girls separately. Active-fit boys had 7.3-7.7 % greater cortical area and thickness compared to inactive-unfit boys (P < 0.05), which was largely due to a 6.4-7.8 % (P < 0.05) greater cortical mass in the posterior-lateral, medial and posterior-medial 66 % tibial regions. Cortical area was not significantly different across PA-fitness categories in girls, but active-fit girls had 6.1 % (P < 0.05) greater SSIpolar compared to inactive-fit girls, which was likely due to their 6.7 % (P < 0.05) greater total bone area. There was also a small region-specific cortical mass benefit in the posterior-medial 66 % tibia cortex in active-fit girls. Higher levels of habitual PA-fitness were associated with small regional-specific gains in 66 % tibial cortical bone mass in pre-pubertal children, particularly boys.

  2. Cortical swallowing processing in early subacute stroke

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    Fischer Maren

    2011-03-01

    Full Text Available Abstract Background Dysphagia is a major complication in hemispheric as well as brainstem stroke patients causing aspiration pneumonia and increased mortality. Little is known about the recovery from dysphagia after stroke. The aim of the present study was to determine the different patterns of cortical swallowing processing in patients with hemispheric and brainstem stroke with and without dysphagia in the early subacute phase. Methods We measured brain activity by mean of whole-head MEG in 37 patients with different stroke localisation 8.2 +/- 4.8 days after stroke to study changes in cortical activation during self-paced swallowing. An age matched group of healthy subjects served as controls. Data were analyzed by means of synthetic aperture magnetometry and group analyses were performed using a permutation test. Results Our results demonstrate strong bilateral reduction of cortical swallowing activation in dysphagic patients with hemispheric stroke. In hemispheric stroke without dysphagia, bilateral activation was found. In the small group of patients with brainstem stroke we observed a reduction of cortical activation and a right hemispheric lateralization. Conclusion Bulbar central pattern generators coordinate the pharyngeal swallowing phase. The observed right hemispheric lateralization in brainstem stroke can therefore be interpreted as acute cortical compensation of subcortically caused dysphagia. The reduction of activation in brainstem stroke patients and dysphagic patients with cortical stroke could be explained in terms of diaschisis.

  3. Imaging of the posterior pelvic floor

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    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.)

  4. Posterior reversible encephalopathy syndrome: a case report

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    Kumkum Srivastava

    2014-08-01

    Full Text Available Posterior Reversible Encephalopathy Syndrome (PRES is a clinic radiological entity, characterized by variable associations of seizure activity, consciousness impairment, headache, visual abnormalities, nausea and vomiting and focal neurological signs. The global incidence of PRES is not known. It can develop in association with conditions like exposure to toxic agents, hypertension, infection and eclampsia was present in 7%. So, here I am presenting a case of our patient of 22 years primigravida, who presented with ante partum eclampsia at 28 weeks of gestation and delivered vaginally by induction of labor. Post-delivery she developed PRES which was diagnosed by MRI. [Int J Reprod Contracept Obstet Gynecol 2014; 3(4.000: 1155-1156

  5. Luxación Posterior de Hombro

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    Álvarez Garcia, J.C.; Fernández Delbrouck, I.; Murcia Mazón, Antonio

    1991-01-01

    Se presentan cuatro casos de luxación posterior de hombro , de etiología trau - mática aguda . Se realiza una reseña de las características anatomopatológicas, del estudio clínico y radiográfico así como del tratamiento que fué conservador en todos los casos, utilizándose sólo en dos casos de reducción inestable fijación con agujas de Kirschner. La valoración de los resultados fué uniformemente buena Th e author s repor t fou r case s o f posterio r shoulde r dislocatio n o ...

  6. Hemifacial spasm and posterior auricular muscle.

    Science.gov (United States)

    Kiziltan, M; Sahin, R; Uzun, N; Kiziltan, G

    2006-09-01

    We aimed to investigate to which extent posterior auricular muscle (PAM) was affected and whether it contributed to the reflex activity in hemifacial spasm (HFS) patients. 19 HFS patients' spasm activities were recorded from facial muscles. Spasm activity of PAM was recorded synchronously on the symptomatic side in all patients. Lateral spread of blink reflex to orbicularis oris and PAMs were recorded in all but two patients. Botulinum toxin was applied to the PAM with the 14 patients presenting tinnitus, "clicking" or a "ticking" sound on the sane side and other positive auricular symptoms. After treatment, there was symptomatic improvement in 9 of 14 patients. The patients presenting with auricular symptoms and showing spasm activity in their PAMs can be thought as a candidate for botulinum toxin treatment scheme.

  7. Posterior antebrachial cutaneous neuropathy. Case report.

    Science.gov (United States)

    Chang, C W; Oh, S J

    1990-01-01

    Posterior antebrachial cutaneous (PABC) neuropathy is rare. Two original cases are reported here. In case 1, the neuropathy is probably due to a traction injury in a reduction operation for humeral fracture. In case 2, it is injured associately with an operation in taking a myocutaneous flap. On examination, both cases showed a decreased sensation to pin-prick over the PABC nerve territories and a positive Tinel's sign near the injured sites. Sensory nerve conduction study of the PABC nerves revealed a low amplitude of the compound nerve action potential (CNAP) and a slow sensory nerve conduction velocity (SNCV) in case 1, and absent CNAP in case 2. Our study showed the sensory nerve conduction test is useful in confirming PABC neuropathy.

  8. Current concepts review: the posterior cruciate ligament.

    Science.gov (United States)

    Fanelli, Gregory C; Beck, John D; Edson, Craig J

    2010-06-01

    Injuries to the posterior cruciate ligament (PCL) and methods of treatment of the injured PCL have historically been surrounded by controversy in the orthopedic community. The infrequent occurrence of PCL injuries and PCL-based, multiple ligament knee injuries has led to limitations in clinical studies and a subsequent lag in basic science and clinical research compared with that for other ligamentous injuries. In recent years, new studies have elucidated the biomechanical function and complex anatomy of the PCL leading to an increased interest in research, understanding, and treatment of these complex injuries. In addition to improved understanding of knee ligament structure and biomechanics, technical advancements in allograft tissue, surgical instrumentation, and graft tensioning and fixation methods and improved surgical techniques and postoperative rehabilitation methods have enhanced the results in PCL reconstruction and PCL-based, multiple ligament knee surgical outcomes.

  9. Posterior cruciate ligament: focus on conflicting issues.

    Science.gov (United States)

    Lee, Yong Seuk; Jung, Young Bok

    2013-12-01

    There is little consensus on how to optimally reconstruct the posterior cruciate ligament (PCL) and the natural history of injured PCL is also unclear. The graft material (autograft vs. allograft), the type of tibial fixation (tibial inlay vs. transtibial tunnel), the femoral tunnel position within the femoral footprint (isometric, central, or eccentric), and the number of bundles in the reconstruction (1 bundle vs. 2 bundles) are among the many decisions that a surgeon must make in a PCL reconstruction. In addition, there is a paucity of information on rehabilitation after reconstruction of the PCL and posterolateral structures. This article focused on the conflicting issues regarding the PCL, and the scientific rationales behind some critical points are discussed.

  10. Posterior adhesive composite resin: a historic review.

    Science.gov (United States)

    Fusayama, T

    1990-11-01

    Since development of the BIS-GMA composite resin, there have been many innovations to improve the physical properties for posterior use. Subsequent development of a caries detector and chemically adhesive composite resin has further revolutionally raised the value of composite resin restoration, replacing the traditional restorative system of mechanical approach by the new system of biological approach. In this system only the infected irreversibly deteriorated insensitive tissue, stainable with the caries detector, is removed painlessly. The cavity is immediately filled with the composite resin with no further tissue reduction for retention or resistance form or extension for prevention. Both enamel and dentin walls are etched by a single etchant without lining. The chemical adhesion to the cavity margin and wall minimizes the marginal failure in size and prevalence and prevents secondary caries penetration along the wall. The chemically adhesive composite resin is thus a useful restorative material much kinder to teeth than amalgam.

  11. Esclerite posterior: características clínicas, associação sistêmica, tratamento e evolução de 23 pacientes Posterior scleritis: clinical features, systemic association, treatment and evolution of 23 patients

    Directory of Open Access Journals (Sweden)

    Danuza de Oliveira Machado

    2009-06-01

    Full Text Available OBJETIVOS: Documentar características clínicas, associações sistêmicas, tratamento e evolução de 23 pacientes com esclerite posterior, examinados no serviço de uveítes da Universidade Federal de Minas Gerais. MÉTODOS: Revisão de todos os pacientes com esclerite atendidos neste serviço, de 1999 até 2006, para identificar aqueles com esclerite posterior. Identificados 23 pacientes, registrados e analisados os dados com relação aos sinais e sintomas oculares, visão, alterações na ecografia, manifestações sistêmicas, tratamento e evolução. RESULTADOS: Dezesseis pacientes do sexo feminino e 7 do sexo masculino com média de idade de 44,7 anos. Esclerite posterior ocorreu associada à esclerite anterior em 10 pacientes, envolvimento unilateral em 17 pacientes e, bilateral simultâneo, em 6 pacientes. Esclerite posterior associada à doença sistêmica ocorreu em 8 pacientes (síndrome de Cogan, tuberculose, granulomatose de Wegener, herpes simples e zoster, aspergilose, retocolite-ulcerativa e sarcoidose. A principal queixa foi dor ocular seguida de embaçamento visual e o sinal fundoscópico que predominou foi o descolamento seroso de retina. O achado mais comum na ecografia foi espessamento da parede escleral observado em 18 pacientes e a principal forma de tratamento, o uso de corticóide sistêmico. Somente 4 pacientes necessitaram de imunossupressor. CONCLUSÃO: Esclerite posterior é doença de difícil diagnóstico e pode ser potencialmente devastadora. Análises estatísticas são incapazes de revelar outras características específicas da esclerite posterior, características clínicas dos pacientes e evolução da doença que poderiam ajudar na identificação dos casos com maior risco de perda visual ou com maior probabilidade de doença sistêmica.PURPOSE: To document the clinical features, systemic association, treatment and evolution of 23 patients with posterior scleritis evaluated in the Uveitis service of the

  12. Posterior α EEG Dynamics Dissociate Current from Future Goals in Working Memory-Guided Visual Search.

    Science.gov (United States)

    de Vries, Ingmar E J; van Driel, Joram; Olivers, Christian N L

    2017-02-08

    Current models of visual search assume that search is guided by an active visual working memory representation of what we are currently looking for. This attentional template for currently relevant stimuli can be dissociated from accessory memory representations that are only needed prospectively, for a future task, and that should be prevented from guiding current attention. However, it remains unclear what electrophysiological mechanisms dissociate currently relevant (serving upcoming selection) from prospectively relevant memories (serving future selection). We measured EEG of 20 human subjects while they performed two consecutive visual search tasks. Before the search tasks, a cue instructed observers which item to look for first (current template) and which second (prospective template). During the delay leading up to the first search display, we found clear suppression of α band (8-14 Hz) activity in regions contralateral to remembered items, comprising both local power and interregional phase synchronization within a posterior parietal network. Importantly, these lateralization effects were stronger when the memory item was currently relevant (i.e., for the first search) compared with when it was prospectively relevant (i.e., for the second search), consistent with current templates being prioritized over future templates. In contrast, event-related potential analysis revealed that the contralateral delay activity was similar for all conditions, suggesting no difference in storage. Together, these findings support the idea that posterior α oscillations represent a state of increased processing or excitability in task-relevant cortical regions, and reflect enhanced cortical prioritization of memory representations that serve as a current selection filter.SIGNIFICANCE STATEMENT Our days are filled with looking for relevant objects while ignoring irrelevant visual information. Such visual search activity is thought to be driven by current goals activated in

  13. Posterior α EEG Dynamics Dissociate Current from Future Goals in Working Memory-Guided Visual Search

    Science.gov (United States)

    2017-01-01

    Current models of visual search assume that search is guided by an active visual working memory representation of what we are currently looking for. This attentional template for currently relevant stimuli can be dissociated from accessory memory representations that are only needed prospectively, for a future task, and that should be prevented from guiding current attention. However, it remains unclear what electrophysiological mechanisms dissociate currently relevant (serving upcoming selection) from prospectively relevant memories (serving future selection). We measured EEG of 20 human subjects while they performed two consecutive visual search tasks. Before the search tasks, a cue instructed observers which item to look for first (current template) and which second (prospective template). During the delay leading up to the first search display, we found clear suppression of α band (8–14 Hz) activity in regions contralateral to remembered items, comprising both local power and interregional phase synchronization within a posterior parietal network. Importantly, these lateralization effects were stronger when the memory item was currently relevant (i.e., for the first search) compared with when it was prospectively relevant (i.e., for the second search), consistent with current templates being prioritized over future templates. In contrast, event-related potential analysis revealed that the contralateral delay activity was similar for all conditions, suggesting no difference in storage. Together, these findings support the idea that posterior α oscillations represent a state of increased processing or excitability in task-relevant cortical regions, and reflect enhanced cortical prioritization of memory representations that serve as a current selection filter. SIGNIFICANCE STATEMENT Our days are filled with looking for relevant objects while ignoring irrelevant visual information. Such visual search activity is thought to be driven by current goals activated

  14. Spike phase synchronization in multiplex cortical neural networks

    Science.gov (United States)

    Jalili, Mahdi

    2017-01-01

    In this paper we study synchronizability of two multiplex cortical networks: whole-cortex of hermaphrodite C. elegans and posterior cortex in male C. elegans. These networks are composed of two connection layers: network of chemical synapses and the one formed by gap junctions. This work studies the contribution of each layer on the phase synchronization of non-identical spiking Hindmarsh-Rose neurons. The network of male C. elegans shows higher phase synchronization than its randomized version, while it is not the case for hermaphrodite type. The random networks in each layer are constructed such that the nodes have the same degree as the original network, thus providing an unbiased comparison. In male C. elegans, although the gap junction network is sparser than the chemical network, it shows higher contribution in the synchronization phenomenon. This is not the case in hermaphrodite type, which is mainly due to significant less density of gap junction layer (0.013) as compared to chemical layer (0.028). Also, the gap junction network in this type has stronger community structure than the chemical network, and this is another driving factor for its weaker synchronizability.

  15. Evaluation and treatment of posterior cruciate ligament injuries: revisited.

    Science.gov (United States)

    Wind, William M; Bergfeld, John A; Parker, Richard D

    2004-01-01

    Current knowledge and treatment of posterior cruciate ligament injuries continue to lag behind that of anterior cruciate ligament injuries. This is the result of the relative infrequency of posterior cruciate ligament injuries and the lack of consensus with respect to its natural history, surgical indications, technique, and postoperative rehabilitation. Recent anatomical and biomechanical studies have improved our understanding of the posterior cruciate ligament in an attempt to reproduce its anatomy and function during reconstruction. The following is a comprehensive review on the evaluation and treatment of posterior cruciate ligament injuries with special focus on the current surgical techniques.

  16. Cortical networks for visual reaching: physiological and anatomical organization of frontal and parietal lobe arm regions.

    Science.gov (United States)

    Johnson, P B; Ferraina, S; Bianchi, L; Caminiti, R

    1996-01-01

    The functional and structural properties of the dorsolateral frontal lobe and posterior parietal proximal arm representations were studied in macaque monkeys. Physiological mapping of primary motor (MI), dorsal premotor (PMd), and posterior parietal (area 5) cortices was performed in behaving monkeys trained in an instructed-delay reaching task. The parietofrontal corticocortical connectivities of these same areas were subsequently examined anatomically by means of retrograde tracing techniques. Signal-, set-, movement-, and position-related directional neuronal activities were distributed nonuniformly within the task-related areas in both frontal and parietal cortices. Within the frontal lobe, moving caudally from PMd to the MI, the activity that signals for the visuo-spatial events leading to target localization decreased, while the activity more directly linked to movement generation increased. Physiological recordings in the superior parietal lobule revealed a gradient-like distribution of functional properties similar to that observed in the frontal lobe. Signal- and set-related activities were encountered more frequently in the intermediate and ventral part of the medial bank of the intraparietal sulcus (IPS), in area MIP. Movement-and position-related activities were distributed more uniformly within the superior parietal lobule (SPL), in both dorsal area 5 and in MIP. Frontal and parietal regions sharing similar functional properties were preferentially connected through their association pathways. As a result of this study, area MIP, and possibly areas MDP and 7m as well, emerge as the parietal nodes by which visual information may be relayed to the frontal lobe arm region. These parietal and frontal areas, along with their association connections, represent a potential cortical network for visual reaching. The architecture of this network is ideal for coding reaching as the result of a combination between visual and somatic information.

  17. Posterior reversible encephalopathy syndrome as a complication of Henoch-Schönlein purpura in a seven-year-old girl.

    Science.gov (United States)

    Dos Santos, Daiane; Langer, Felipe Welter; Dos Santos, Tatiane; Rafael Tronco Alves, Giordano; Feiten, Marisa; Teixeira de Paula Neto, Walter

    2017-02-01

    Introduction Henoch-Schönlein purpura is a multisystem small vessel vasculitis. Neurologic manifestations are uncommon. Posterior reversible encephalopathy syndrome is a rare complication of Henoch-Schönlein purpura with typical clinical and neuroimaging findings that occurs most commonly in the setting of severe hypertension and renal injury. Case presentation A seven-year-old girl was admitted to our institution presenting with clinical and laboratory findings suggestive of Henoch-Schönlein purpura. Glucocorticoid therapy was initiated, but five days following her admission, she developed altered consciousness, seizures, arterial hypertension, and cortical blindness. Brain MRI scan revealed areas of vasogenic oedema in parieto-occipital lobes, consistent with posterior reversible encephalopathy syndrome. She was immediately initiated on antihypertensives and antiepileptics, which successfully improved her neurologic symptoms. Further laboratory work-up disclosed a rapidly progressive glomerulonephritis secondary to Henoch-Schönlein purpura that was the likely cause of her sudden blood pressure elevation. Immunosuppressive therapy was undertaken, and at one-year follow-up, the patient exhibited complete renal and neurologic recovery. Conclusion Posterior reversible encephalopathy syndrome is a severe complication of Henoch-Schönlein purpura. If promptly diagnosed and treated, children with Henoch-Schönlein purpura presenting with posterior reversible encephalopathy syndrome usually have a good prognosis. Clinicians should be familiar with the characteristic presentation of posterior reversible encephalopathy syndrome and be aware that hypertension and renal injury may predispose Henoch-Schönlein purpura patients to developing this complication.

  18. Disrupted cortical connectivity theory as an explanatory model for autism spectrum disorders

    Science.gov (United States)

    Kana, Rajesh K.; Libero, Lauren E.; Moore, Marie S.

    2011-12-01

    Recent findings of neurological functioning in autism spectrum disorder (ASD) point to altered brain connectivity as a key feature of its pathophysiology. The cortical underconnectivity theory of ASD (Just et al., 2004) provides an integrated framework for addressing these new findings. This theory suggests that weaker functional connections among brain areas in those with ASD hamper their ability to accomplish complex cognitive and social tasks successfully. We will discuss this theory, but will modify the term underconnectivity to ‘disrupted cortical connectivity’ to capture patterns of both under- and over-connectivity in the brain. In this paper, we will review the existing literature on ASD to marshal supporting evidence for hypotheses formulated on the disrupted cortical connectivity theory. These hypotheses are: 1) underconnectivity in ASD is manifested mainly in long-distance cortical as well as subcortical connections rather than in short-distance cortical connections; 2) underconnectivity in ASD is manifested only in complex cognitive and social functions and not in low-level sensory and perceptual tasks; 3) functional underconnectivity in ASD may be the result of underlying anatomical abnormalities, such as problems in the integrity of white matter; 4) the ASD brain adapts to underconnectivity through compensatory strategies such as overconnectivity mainly in frontal and in posterior brain areas. This may be manifested as deficits in tasks that require frontal-parietal integration. While overconnectivity can be tested by examining the cortical minicolumn organization, long-distance underconnectivity can be tested by cognitively demanding tasks; and 5) functional underconnectivity in brain areas in ASD will be seen not only during complex tasks but also during task-free resting states. We will also discuss some empirical predictions that can be tested in future studies, such as: 1) how disrupted connectivity relates to cognitive impairments in skills

  19. Disrupted cortical connectivity theory as an explanatory model for autism spectrum disorders.

    Science.gov (United States)

    Kana, Rajesh K; Libero, Lauren E; Moore, Marie S

    2011-12-01

    Recent findings of neurological functioning in autism spectrum disorder (ASD) point to altered brain connectivity as a key feature of its pathophysiology. The cortical underconnectivity theory of ASD (Just et al., 2004) provides an integrated framework for addressing these new findings. This theory suggests that weaker functional connections among brain areas in those with ASD hamper their ability to accomplish complex cognitive and social tasks successfully. We will discuss this theory, but will modify the term underconnectivity to 'disrupted cortical connectivity' to capture patterns of both under- and over-connectivity in the brain. In this paper, we will review the existing literature on ASD to marshal supporting evidence for hypotheses formulated on the disrupted cortical connectivity theory. These hypotheses are: 1) underconnectivity in ASD is manifested mainly in long-distance cortical as well as subcortical connections rather than in short-distance cortical connections; 2) underconnectivity in ASD is manifested only in complex cognitive and social functions and not in low-level sensory and perceptual tasks; 3) functional underconnectivity in ASD may be the result of underlying anatomical abnormalities, such as problems in the integrity of white matter; 4) the ASD brain adapts to underconnectivity through compensatory strategies such as overconnectivity mainly in frontal and in posterior brain areas. This may be manifested as deficits in tasks that require frontal-parietal integration. While overconnectivity can be tested by examining the cortical minicolumn organization, long-distance underconnectivity can be tested by cognitively demanding tasks; and 5) functional underconnectivity in brain areas in ASD will be seen not only during complex tasks but also during task-free resting states. We will also discuss some empirical predictions that can be tested in future studies, such as: 1) how disrupted connectivity relates to cognitive impairments in skills such

  20. Evidence for visual cortical area homologs in cat and macaque monkey.

    Science.gov (United States)

    Payne, B R

    1993-01-01

    The maps of visuotopically discrete visual cerebral cortical areas in the cat and the macaque monkey are compared and gaps in knowledge are identified that limit such comparisons. Cat areas 17, 18, and 19 can be equated with macaque areas V1, V2, and V3, respectively, based on criteria of relative position in the cortical mantle, internal organization of visual field representations, and trans- and subcortical connections. Using these same criteria, a visual area on the medial bank of the lateral suprasylvian sulcus (area PMLS) in the cat can be equated with macaque area V5. The equivalences are supported by data on neuronal receptive field properties and the contributions the areas make to visual behavior. Although the data are scanty for most other visual areas, there are enough data tentatively to equate collectively cat areas 20a and 20b with macaque areas TF and TH and to liken cat areas 21a and 21b with macaque area V4. What is not clear is if there is a region in cat that is equivalent to area TE in the macaque monkey. If there is, it likely lies on the banks of the posterior suprasylvian sulcus between areas 20 and 21 and the polysensory cortex of the posterior ectosylvian gyrus. Knowledge gained from prior research on macaque areas V4 and TE can be used to formulate specific additional investigations of cat area 21 and the uncharted posterior suprasylvian sulcus. In addition, prior investigations carried out on cat area 20 can be used to devise specific explorations of macaque areas TF and TH.

  1. 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.

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

    Energy Technology Data Exchange (ETDEWEB)

    Spitzer, C.; Kosinski, C.M. [University Hospital of RWTH Aachen, Department of Neurology, Aachen (Germany); Mull, M. [University Hospital of RWTH Aachen, Department of Neuroradiology, Aachen (Germany); Rohde, V. [University Hospital of RWTH Aachen, Department of Neurosurgery, Aachen (Germany)

    2005-07-01

    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.)

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

    Directory of Open Access Journals (Sweden)

    Alexandre E. V. Kokron

    2001-06-01

    Full Text Available 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 posterior cruciate ligament isometry. The authors conclude that most studies agree that femoral insertion of the ligament is more important for isometry, and that there is a most isometric line or area inside the femoral insertion, perpendicular to the roof of the intercondilar fossa, approximately 10 to 14mm from its anterior opening.

  4. 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

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    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

  5. Minimal-invasive posterior approach in the treatment of the posterior wall fractures of the acetabulum.

    Science.gov (United States)

    Spagnolo, Rosario; Bonalumi, Matteo; Pace, Fabrizio; Capitani, Dario

    2009-05-01

    We examined patients affected by a posterior wall fracture of the acetabulum treated with a minimally invasive posterior approach (from 12 to 18 cm). During 2004-2006 19 patients were treated by this approach. 4 patients had a combined surgery by the ileo-inguinal approach. Fracture fixation was performed using reconstruction plates and screws. All the patients were studied with typical X-rays projection for pelvis and iliac oblique view and obturator oblique view (Judet view) and CT scan with 3D reconstruction. After 3 months a CT scan was performed on about 30% of our patients, which demonstrated the perfect healing of the fractures. The most important advantages we observed using this approach were a lesser split of the gluteus maximus and no risk of damage for the superior gluteal nerve. In the early post-operative rehabilitation we examined the trophism of the gluteus maximus, which was found to be better than in patients treated with the typical Kocher-Langenbeck approach. The only absolute contraindication for this technique is in obese patients. The post-operative complications include one case of heterotypic ossification of the gluteus minimus and one case of peroneal-nerve palsy with the spontaneous and complete recovery within 6 months. According to our experience this kind of approach could be used for posterior wall fracture of the pelvis and it can be extended to transverse fractures. In the post-operative period the greatest advantage is the lesser muscle damage and therefore a most effective rehabilitation.

  6. Cognitive signals for brain-machine interfaces in posterior parietal cortex include continuous 3D trajectory commands.

    Science.gov (United States)

    Hauschild, Markus; Mulliken, Grant H; Fineman, Igor; Loeb, Gerald E; Andersen, Richard A

    2012-10-16

    Cortical neural prosthetics extract command signals from the brain with the goal to restore function in paralyzed or amputated patients. Continuous control signals can be extracted from the motor cortical areas, whereas neural activity from posterior parietal cortex (PPC) can be used to decode cognitive variables related to the goals of movement. Because typical activities of daily living comprise both continuous control tasks such as reaching, and tasks benefiting from discrete control such as typing on a keyboard, availability of both signals simultaneously would promise significant increases in performance and versatility. Here, we show that PPC can provide 3D hand trajectory information under natural conditions that would be encountered for prosthetic applications, thus allowing simultaneous extraction of continuous and discrete signals without requiring multisite surgical implants. We found that limb movements can be decoded robustly and with high accuracy from a small population of neural units under free gaze in a complex 3D point-to-point reaching task. Both animals' brain-control performance improved rapidly with practice, resulting in faster target acquisition and increasing accuracy. These findings disprove the notion that the motor cortical areas are the only candidate areas for continuous prosthetic command signals and, rather, suggests that PPC can provide equally useful trajectory signals in addition to discrete, cognitive variables. Hybrid use of continuous and discrete signals from PPC may enable a new generation of neural prostheses providing superior performance and additional flexibility in addressing individual patient needs.

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

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    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.

  8. Retinal nerve fiber layer atrophy as relevant feature for diffuse unilateral subacute neuroretinitis (DUSN: case series Atrofia das camadas de fibras nervosas da retina como característica relevante na neurorretinite subaguda difusa unilateral (DUSN: série de casos

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    Antonio Marcelo Barbante Casella

    2010-04-01

    Full Text Available PURPOSE: To report the findings of optical coherence tomography (OCT in three cases of diffuse unilateral subacute neuroretinitis (DUSN. METHODS: Three young patients with confirmed diagnosis of diffuse unilateral subacute neuroretinitis were followed-up using Stratus® OCT. RESULTS: Optical coherence tomography findings included retinal nerve fiber layer atrophy and focal edema where the worm was initially lodged. In two patients we could identify the worm by optical coherence tomography as an area of hiper-reflectivity. The worms were laser photocoagulated and post-treatment optical coherence tomography scanning revealed improvement of edema, nerve fiber layer thinning and a retinal hyper-reflectivity where laser had been applied. CONCLUSION: The main finding reported here is the potential of optical coherence tomography in detecting the presence of retinal nerve fiber layer atrophy and focal retinal edema in areas affected by the worm. Optical coherence tomography can be used to distinguish diffuse unilateral subacute neuroretinitis from other mimicking diseases like punctate outer retinitis, when there are no retinal fiber layer atrophy.OBJETIVO: Demonstrar os achados da tomografia de coerência óptica em três casos de neurorretinite subaguda difusa unilateral (DUSN. MÉTODOS: Os pacientes com diagnóstico confirmado de neurorretinite subaguda difusa unilateral realizaram seguimento pré e pós-tratamento por meio da tomografia de coerência óptica, Stratus® OCT. RESULTADOS: Os achados marcantes da tomografia de coerência óptica foram a atrofia das camadas de fibras nervosas da retina e edema da retina localizado em áreas nas quais a larva esteve. Em dois pacientes pôde-se localizar a larva no espaço sub-retiniano por meio da tomografia de coerência óptica, que se traduziu por pequena área densa (hiperrefletividade. As larvas foram fotocoaguladas a laser e os achados da tomografia de coerência óptica após o tratamento

  9. 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

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    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.

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

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    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.

  11. 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.

  12. Defect in Posterior Arch of Atlas in Myelomeningocele

    NARCIS (Netherlands)

    G. Blaauw (Gerhard)

    1971-01-01

    textabstractThe posterior arches of the cervical vertebrae of 30 children who died with a myelomeningocele in the lower thoracic, lumbar or sacral region were examined; in 70 per cent of these cases a defect was found in the posterior arch of the atlas, which was bridged by a firm fibrous band. Alté

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

    NARCIS (Netherlands)

    H.K. van Dijk (Herman); T. 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 or

  14. Clinical profile and prognosis of patients with posterior circulation stroke

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    Kavita J. Rawat

    2016-12-01

    Conclusions: Posterior circulation stroke present with a wide variety of symptoms. Episodes are often staggering and more protracted than those of anterior circulation stroke. Further studies are needed to determine the safest and most effective treatment modalities for the various types of posterior circulation stroke. [Int J Res Med Sci 2016; 4(12.000: 5159-5164

  15. Hindfoot endoscopy for posterior ankle impingement. Surgical technique

    NARCIS (Netherlands)

    van Dijk, C.N.; de Leeuw, P.A.J.; Scholten, P.E.

    2009-01-01

    BACKGROUND: The surgical treatment of posterior ankle impingement is associated with a high rate of complications and a substantial time to recover. An endoscopic approach to the posterior ankle (hindfoot endoscopy) may lack these disadvantages. We hypothesized that hindfoot endoscopy causes less mo

  16. Combat Veterans with PTSD after Mild TBI Exhibit Greater ERPs from Posterior-medial Cortical Areas While Appraising Facial Features

    Science.gov (United States)

    2014-01-01

    within the past 30 days; (2) life- time history of bipolar disorder , attention deficit hyperactivity disorder , or psychotic disorder ; or (3) acute medical...Arbisi, P.A., Thuras, P., 2011. Longitudinal effects of mild traumatic brain injury and posttraumatic stress disorder comorbidity on postdeployment...The effects of temporal unpredictability in anticipation of negative events in combat veterans with PTSD. J. Affect. Disord . 146, 426–432. Simmons, A.N

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

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    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.

  18. Rare Posterior Pharyngeal Mass: Atypical Marginal Zone Hyperplasia.

    Science.gov (United States)

    Eliçora, Sultan Şevik; Güven, Mehmet; Varli, Ali F; Yilmaz, Mahmut S; Alponat, Selin

    2016-03-01

    Cases of posterior pharyngeal masses are quite rare, and are typically derived from schwannoma or encephalocele, or are of vascular or infectious origin. They are clinically significant due to their tendency to cause airway obstruction. The aim of this study was to present a rare atypical marginal hyperplasia case of a posterior pharyngeal wall mass. A 10-year-old male was admitted to our clinic with dyspnea. A plane-surfaced 4 × 3 × 3 cm mass was observed on the posterior pharyngeal wall upon physical examination. The patient underwent magnetic resonance imaging and surgical treatment. Following excision of material from the patient's mass, a pathologic diagnosis of atypical marginal zone hyperplasia was made. Atypical marginal zone hyperplasia of the posterior pharyngeal wall has not yet been reported in the literature. Marginal zone hyperplasia associated with a lymphoproliferative disease should be considered when making differential diagnoses of posterior pharyngeal wall masses.

  19. Impaired visual short-term memory capacity is distinctively associated with structural connectivity of the posterior thalamic radiation and the splenium of the corpus callosum in preterm-born adults.

    Science.gov (United States)

    Menegaux, Aurore; Meng, Chun; Neitzel, Julia; Bäuml, Josef G; Müller, Hermann J; Bartmann, Peter; Wolke, Dieter; Wohlschläger, Afra M; Finke, Kathrin; Sorg, Christian

    2017-02-07

    Preterm birth is associated with an increased risk for lasting changes in both the cortico-thalamic system and attention; however, the link between cortico-thalamic and attention changes is as yet little understood. In preterm newborns, cortico-cortical and cortico-thalamic structural connectivity are distinctively altered, with increased local clustering for cortico-cortical and decreased integrity for cortico-thalamic connectivity. In preterm-born adults, among the various attention functions, visual short-term memory (vSTM) capacity is selectively impaired. We hypothesized distinct associations between vSTM capacity and the structural integrity of cortico-thalamic and cortico-cortical connections, respectively, in preterm-born adults. A whole-report paradigm of briefly presented letter arrays based on the computationally formalized Theory of Visual Attention (TVA) was used to quantify parameter vSTM capacity in 26 preterm- and 21 full-term-born adults. Fractional anisotropy (FA) of posterior thalamic radiations and the splenium of the corpus callosum obtained by diffusion tensor imaging were analyzed by tract-based spatial statistics and used as proxies for cortico-thalamic and cortico-cortical structural connectivity. The relationship between vSTM capacity and cortico-thalamic and cortico-cortical connectivity, respectively, was significantly modified by prematurity. In full-term-born adults, the higher FA in the right posterior thalamic radiation the higher vSTM capacity; in preterm-born adults this FA-vSTM-relationship was inversed. In the splenium, higher FA was correlated with higher vSTM capacity in preterm-born adults, whereas no significant relationship was evident in full-term-born adults. These results indicate distinct associations between cortico-thalamic and cortico-cortical integrity and vSTM capacity in preterm-and full-term-born adults. Data suggest compensatory cortico-cortical fiber re-organization for attention deficits after preterm delivery.

  20. [Posterior reversible encephalopathy: beyond the original description].

    Science.gov (United States)

    Avecillas-Chasín, Josué M; Matías-Guiu, Jordi A; Bautista-Balbás, Luis

    2015-07-16

    Introduccion. La encefalopatia posterior reversible (EPR) es una entidad clinicorradiologica caracterizada tipicamente por cuadros de cefalea, alteraciones visuales y crisis epilepticas, asociada a edema vasogeno corticosubcortical reversible en la neuroimagen. Objetivo. Presentar una revision de los aspectos fisiopatologicos de esta entidad y tambien de las asociaciones de la EPR descritas en la bibliografia. Desarrollo. Existe una serie de factores desencadenantes bien conocidos, como las crisis hipertensivas, la eclampsia o ciertos medicamentos. La descripcion de cada vez mas casos atipicos desde un punto de vista clinico y radiologico, asi como de posibles nuevos factores desencadenantes, obliga a una redefinicion de la entidad. Conclusiones. La EPR es un conjunto de manifestaciones clinicas y radiologicas que no se pueden enmarcar dentro la palabra 'sindrome'. Aunque la EPR se ha comunicado como irreversible en ciertos casos, el concepto de reversibilidad debe mantenerse en la definicion de esta entidad, ya que, en la mayor parte de los casos, el rapido control de la condicion desencadenante de la EPR permite la reversibilidad de las lesiones.

  1. Posterior endoscopic discectomy: Results in 300 patients

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    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.

  2. Gastroesophageal reflux disease correlation with posterior laryngitis

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    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.

  3. Dynamic properties of the posterior cricoarytenoid muscle.

    Science.gov (United States)

    Cooper, D S; Shindo, M; Sinha, U; Hast, M H; Rice, D H

    1994-12-01

    The aim of this research was to investigate the contractile properties of the posterior cricoarytenoid (PCA) muscle. Simultaneous measurements were made of the isometric force, temperature, and electromyographic activity of the dorsal cricoarytenoid muscle of anesthetized dogs during supramaximal stimulation of the recurrent laryngeal nerve for twitch and tetanic contraction. The conduction delay between stimulation of the recurrent nerve at the level of the larynx and the onset of the muscle action potential averaged 2.0 +/- 0.2 milliseconds (ms), and the latent period between the onset of electrical activity of the muscle and the onset of contraction had a mean duration of 3.3 +/- 0.8 ms. The mean of isometric contraction times found was 33.3 +/- 2.0 ms, shorter than most previous studies of canine PCA muscle. Tetanic frequency defined as smooth contraction was higher than previous estimates. Considerations of scaling of physiological time based on animal mass were applied to analysis of the experimental findings to make possible systematic comparison of previous findings across species and animal size.

  4. Posterior Probability Matching and Human Perceptual Decision Making.

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    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

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

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    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

  6. Neurodynamics of somatosensory cortices studied by magnetoencephelography.

    Science.gov (United States)

    Kishida, Kuniharu

    2013-09-01

    From the viewpoint of statistical inverse problems, identification of transfer functions in feedback models is applied for neurodynamics of somatosensory cortices, and brain communication among active regions can be expressed in terms of transfer functions. However, brain activities have been investigated mainly by averaged waveforms in the conventional magnetoencephalography analysis, and thus brain communication among active regions has not yet been identified. It is shown that brain communication among two more than three brain regions is determined, when fluctuations related to concatenate averaged waveforms can be obtained by using a suitable blind source separation method. In blind identification of feedback model, some transfer functions or their impulse responses between output variables of current dipoles corresponding to active regions are identified from reconstructed time series data of fluctuations by the method of inverse problem. Neurodynamics of somatosensory cortices in 5 Hz median nerve stimuli can be shown by cerebral communication among active regions of somatosensory cortices in terms of impulse responses of feedback model.

  7. Unusual combination of posterior femoral head dislocation with anterior and posterior wall fractures in the ipsilateral acetabulum.

    Science.gov (United States)

    Chen, Wei; Su, Yanling; Zhang, Yingze; Zhang, Qi; Zheng, Zhanle; Pan, Jinshe

    2010-06-09

    Although hip dislocation combined with acetabular fracture is not an uncommon injury, anterior acetabular wall fractures rarely occur in patients who have posterior fracture-dislocations of the hip. This article presents a unique case of anterior and posterior wall fractures of the ipsilateral acetabulum in a patient who sustained traumatic posterior hip dislocation that resulted from a high-speed motor vehicle accident. The initial imaging evaluation, which did not include the obturator oblique view, revealed no concomitant anterior acetabular wall fracture. Repeated manipulative reductions were unsuccessful in reducing the displaced hip joint. Pelvic computed tomography (CT) scans revealed the initially missed anterior acetabular wall fracture fragments incarcerated in the left hip joint in addition to the hip dislocation and the posterior acetabular wall fracture. The incarcerated bone fragments lay between the anterior wall and the femoral head, and between the posterior wall and the femoral head, which appeared to derive from both anterior and posterior acetabular walls, respectively. Open reduction and internal fixation was performed to manage the posterior dislocation and associated acetabular fractures. Intraoperatively, the major anterior wall fragment was used to reconstruct the defected posterior wall. This case highlights the necessity of suspicion and pre- and postoperative monitoring of the obturator oblique view and CT scans to detect the potentially existing anterior acetabular wall fracture. Early surgical intervention is important to guarantee satisfactory outcomes of such complex fracture-dislocation injuries.

  8. No difference in gait between posterior cruciate retention and the posterior stabilized design after total knee arthroplasty

    NARCIS (Netherlands)

    van den Boom, Lennard G. H.; Halbertsma, Jan P. K.; van Raaij, Jos J. A. M.; Brouwer, Reinoud W.; Bulstra, Sjoerd K.; van den Akker-Scheek, Inge

    2014-01-01

    In the present study, knee joint kinematics (e.g. knee flexion/extension) and kinetics (e.g. knee flexion moments) are assessed after total knee arthroplasty (TKA) between patients implanted with either a unilateral posterior stabilized (PS) and a posterior cruciate-retaining (PCR) design. It was hy

  9. Temporal changes in cortical activation during conditioned pain modulation (CPM), a LORETA study.

    Science.gov (United States)

    Moont, Ruth; Crispel, Yonatan; Lev, Rina; Pud, Dorit; Yarnitsky, David

    2011-07-01

    For most healthy subjects, both subjective pain ratings and pain-evoked potentials are attenuated under conditioned pain modulation (CPM; formerly termed diffuse noxious inhibitory controls, or DNIC). Although essentially spinal-bulbar, this inhibition is under cortical control. This is the first study to observe temporal as well as spatial changes in cortical activations under CPM. Specifically, we aimed to investigate the interplay of areas involved in the perception and processing of pain and those involved in controlling descending inhibition. We examined brief consecutive poststimulus time windows of 50 ms using a method of source-localization from pain evoked potentials, sLORETA. This enabled determination of dynamic changes in localized cortical generators evoked by phasic noxious heat stimuli to the left volar forearm in healthy young males, with and without conditioning hot-water pain to the right hand. We found a CPM effect characterized by an initial increased activation in the orbitofrontal cortex (OFC) and amygdala at 250-300 ms poststimulus, which was correlated with the extent of psychophysical pain reduction. This was followed by reduced activations in the primary and secondary somatosensory cortices, supplementary motor area, posterior insula, and anterior cingulate cortex from 400 ms poststimulus. Our findings show that the prefrontal pain-controlling areas of OFC and amygdala increase their activity in parallel with subjective pain reduction under CPM, and that this increased activity occurs prior to reductions in activations of the pain sensory areas. In conclusion, achieving pain inhibition by the CPM process seems to be under control of the OFC and the amygdala.

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

    Science.gov (United States)

    Lischinsky, Julieta E.; Skocic, Jovanka; Clairman, Hayyah; Rovet, Joanne

    2016-01-01

    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 10–12 years born to women treated for preexisting or de novo hypothyroidism in 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 that 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 reflecting both

  11. Playing and listening to tailor-made notched music: cortical plasticity induced by unimodal and multimodal training in tinnitus patients.

    Science.gov (United States)

    Pape, Janna; Paraskevopoulos, Evangelos; Bruchmann, Maximilian; Wollbrink, Andreas; Rudack, Claudia; Pantev, Christo

    2014-01-01

    BACKGROUND. The generation and maintenance of tinnitus are assumed to be based on maladaptive functional cortical reorganization. Listening to modified music, which contains no energy in the range of the individual tinnitus frequency, can inhibit the corresponding neuronal activity in the auditory cortex. Music making has been shown to be a powerful stimulator for brain plasticity, inducing changes in multiple sensory systems. Using magnetoencephalographic (MEG) and behavioral measurements we evaluated the cortical plasticity effects of two months of (a) active listening to (unisensory) versus (b) learning to play (multisensory) tailor-made notched music in nonmusician tinnitus patients. Taking into account the fact that uni- and multisensory trainings induce different patterns of cortical plasticity we hypothesized that these two protocols will have different affects. RESULTS. Only the active listening (unisensory) group showed significant reduction of tinnitus related activity of the middle temporal cortex and an increase in the activity of a tinnitus-coping related posterior parietal area. CONCLUSIONS. These findings indicate that active listening to tailor-made notched music induces greater neuroplastic changes in the maladaptively reorganized cortical network of tinnitus patients while additional integration of other sensory modalities during training reduces these neuroplastic effects.

  12. Anxious/Depressed Symptoms are Linked to Right Ventromedial Prefrontal Cortical Thickness Maturation in Healthy Children and Young Adults

    Science.gov (United States)

    Ducharme, Simon; Albaugh, Matthew D.; Hudziak, James J.; Botteron, Kelly N.; Nguyen, Tuong-Vi; Truong, Catherine; Evans, Alan C.; Karama, Sherif; Ball, William S.; Byars, Anna Weber; Schapiro, Mark; Bommer, Wendy; Carr, April; German, April; Dunn, Scott; Rivkin, Michael J.; Waber, Deborah; Mulkern, Robert; Vajapeyam, Sridhar; Chiverton, Abigail; Davis, Peter; Koo, Julie; Marmor, Jacki; Mrakotsky, Christine; Robertson, Richard; McAnulty, Gloria; Brandt, Michael E.; Fletcher, Jack M.; Kramer, Larry A.; Yang, Grace; McCormack, Cara; Hebert, Kathleen M.; Volero, Hilda; Botteron, Kelly; McKinstry, Robert C.; Warren, William; Nishino, Tomoyuki; Almli, C. Robert; Todd, Richard; Constantino, John; McCracken, James T.; Levitt, Jennifer; Alger, Jeffrey; O'Neil, Joseph; Toga, Arthur; Asarnow, Robert; Fadale, David; Heinichen, Laura; Ireland, Cedric; Wang, Dah-Jyuu; Moss, Edward; Zimmerman, Robert A.; Bintliff, Brooke; Bradford, Ruth; Newman, Janice; Evans, Alan C.; Arnaoutelis, Rozalia; Pike, G. Bruce; Collins, D. Louis; Leonard, Gabriel; Paus, Tomas; Zijdenbos, Alex; Das, Samir; Fonov, Vladimir; Fu, Luke; Harlap, Jonathan; Leppert, Ilana; Milovan, Denise; Vins, Dario; Zeffiro, Thomas; Van Meter, John; Lange, Nicholas; Froimowitz, Michael P.; Botteron, Kelly; Almli, C. Robert; Rainey, Cheryl; Henderson, Stan; Nishino, Tomoyuki; Warren, William; Edwards, Jennifer L.; Dubois, Diane; Smith, Karla; Singer, Tish; Wilber, Aaron A.; Pierpaoli, Carlo; Basser, Peter J.; Chang, Lin-Ching; Koay, Chen Guan; Walker, Lindsay; Freund, Lisa; Rumsey, Judith; Baskir, Lauren; Stanford, Laurence; Sirocco, Karen; Gwinn-Hardy, Katrina; Spinella, Giovanna; McCracken, James T.; Alger, Jeffry R.; Levitt, Jennifer; O'Neill, Joseph

    2014-01-01

    The relationship between anxious/depressed traits and neuromaturation remains largely unstudied. Characterizing this relationship during healthy neurodevelopment is critical to understanding processes associated with the emergence of child/adolescent onset mood/anxiety disorders. In this study, mixed-effects models were used to determine longitudinal cortical thickness correlates of Child Behavior Checklist (CBCL) and Young Adult Self Report Anxious/Depressed scores in healthy children. Analyses included 341 subjects from 4.9 to 22.3 year-old with repeated MRI at up to 3 time points, at 2-year intervals (586 MRI scans). There was a significant “CBCL Anxious/Depressed by Age” interaction on cortical thickness in the right ventromedial prefrontal cortex (vmPFC), including the medial orbito-frontal, gyrus rectus, and subgenual anterior cingulate areas. Anxious/Depressed scores were negatively associated with thickness at younger ages (<9 years), but positively associated with thickness at older ages (15–22 years), with the shift in polarity occurring around age 12. This was secondary to a slower rate of vmPFC cortical thinning in subjects with higher scores. In young adults (18–22 years), Anxious/Depressed scores were also positively associated with precuneus/posterior cingulate cortical thickness. Potential neurobiological mechanisms underlying this maturation pattern are proposed. These results demonstrate the dynamic impact of age on relations between vmPFC and negative affect in the developing brain. PMID:23749874

  13. Playing and Listening to Tailor-Made Notched Music: Cortical Plasticity Induced by Unimodal and Multimodal Training in Tinnitus Patients

    Directory of Open Access Journals (Sweden)

    Janna Pape

    2014-01-01

    Full Text Available Background. The generation and maintenance of tinnitus are assumed to be based on maladaptive functional cortical reorganization. Listening to modified music, which contains no energy in the range of the individual tinnitus frequency, can inhibit the corresponding neuronal activity in the auditory cortex. Music making has been shown to be a powerful stimulator for brain plasticity, inducing changes in multiple sensory systems. Using magnetoencephalographic (MEG and behavioral measurements we evaluated the cortical plasticity effects of two months of (a active listening to (unisensory versus (b learning to play (multisensory tailor-made notched music in nonmusician tinnitus patients. Taking into account the fact that uni- and multisensory trainings induce different patterns of cortical plasticity we hypothesized that these two protocols will have different affects. Results. Only the active listening (unisensory group showed significant reduction of tinnitus related activity of the middle temporal cortex and an increase in the activity of a tinnitus-coping related posterior parietal area. Conclusions. These findings indicate that active listening to tailor-made notched music induces greater neuroplastic changes in the maladaptively reorganized cortical network of tinnitus patients while additional integration of other sensory modalities during training reduces these neuroplastic effects.

  14. Acesso posterior para implante de peso de ouro Posterior approach to gold weight implant

    Directory of Open Access Journals (Sweden)

    Filipe José Pereira

    2008-10-01

    Full Text Available OBJETIVO: Demonstrar uma técnica inovadora de implante de peso de ouro via posterior e avaliar sua efetividade e possíveis complicações. Os resultados serão comparados com a literatura existente sobre a técnica via anterior, há muito tempo pouco modificada. MÉTODOS: Foi realizado um estudo prospectivo (seqüência de casos com pacientes que apresentavam, há mais de 6 meses, lagoftalmo paralítico, independentemente da etiologia, atendidos no Departamento de Oculoplástica do Serviço de Oftalmologia do Hospital Governador Celso Ramos - SC, entre o período de fevereiro de 2006 a fevereiro de 2007, com indicação do implante de peso de ouro na pálpebra superior. A nova técnica via posterior foi realizada por apenas dois cirurgiões. RESULTADOS: Treze pacientes com lagoftalmo paralítico, 9 homens e 4 mulheres com idade média de 53,07 anos (variando de 17 a 73, foram submetidos ao implante de peso de ouro pela técnica via posterior. O período de acompanhamento desses pacientes foi de 2 meses a 1 ano, com média de 6,30 meses. Em 3 pacientes, o peso implantado causou assimetria na distância margem-reflexo (DMR na posição primária do olhar - ptose de 2 mm em 2 pacientes e 4 mm em 1 paciente. CONCLUSÕES: Embora tal técnica venha exibindo um resultado sistematicamente satisfatório, os autores acreditam que seja essencial o acompanhamento dos pacientes por um tempo maior a fim de comprovar a sustentabilidade de sua eficácia.PURPOSE: To demonstrate an innovative technique of gold weight implantation through a posterior approach and evaluate its effectiveness and possible complications. The results will be compared to the other existing technique through anterior approach which has been unchanged for a long time, according to the literature. METHODS: A prospective study (sequence of cases was undertaken with patients who presented paralytic lagophthalmos for over 6 months. These patients presented many different etiologies and were

  15. The ontogeny of the cortical language network.

    Science.gov (United States)

    Skeide, Michael A; Friederici, Angela D

    2016-05-01

    Language-processing functions follow heterogeneous developmental trajectories. The human embryo can already distinguish vowels in utero, but grammatical complexity is usually not fully mastered until at least 7 years of age. Examining the current literature, we propose that the ontogeny of the cortical language network can be roughly subdivided into two main developmental stages. In the first stage extending over the first 3 years of life, the infant rapidly acquires bottom-up processing capacities, which are primarily implemented bilaterally in the temporal cortices. In the second stage continuing into adolescence, top-down processes emerge gradually with the increasing functional selectivity and structural connectivity of the left inferior frontal cortex.

  16. Elemental mercury poisoning probably causes cortical myoclonus.

    Science.gov (United States)

    Ragothaman, Mona; Kulkarni, Girish; Ashraf, Valappil V; Pal, Pramod K; Chickabasavaiah, Yasha; Shankar, Susarla K; Govindappa, Srikanth S; Satishchandra, Parthasarthy; Muthane, Uday B

    2007-10-15

    Mercury toxicity causes postural tremors, commonly referred to as "mercurial tremors," and cerebellar dysfunction. A 23-year woman, 2 years after injecting herself with elemental mercury developed disabling generalized myoclonus and ataxia. Electrophysiological studies confirmed the myoclonus was probably of cortical origin. Her deficits progressed over 2 years and improved after subcutaneous mercury deposits at the injection site were surgically cleared. Myoclonus of cortical origin has never been described in mercury poisoning. It is important to ask patients presenting with jerks about exposure to elemental mercury even if they have a progressive illness, as it is a potentially reversible condition as in our patient.

  17. Cortical activation elicited by unrecognized stimuli

    Directory of Open Access Journals (Sweden)

    Badgaiyan Rajendra D

    2006-05-01

    Full Text Available Abstract Background It is unclear whether a stimulus that cannot be recognized consciously, could elicit a well-processed cognitive response. Methods We used functional imaging to examine the pattern of cortical activation elicited by unrecognized stimuli during memory processing. Subjects were given a recognition task using recognizable and non-recognizable subliminal stimuli. Results Unrecognized stimuli activated the cortical areas that are associated with retrieval attempt (left prefrontal, and novelty detection (left hippocampus. This indicates that the stimuli that were not consciously recognized, activated neural network associated with aspects of explicit memory processing. Conclusion Results suggest that conscious recognition of stimuli is not necessary for activation of cognitive processing.

  18. 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.

  19. Effect of posterior condylar offset on clinical results after posterior-stabilized total knee arthroplasty

    Institute of Scientific and Technical Information of China (English)

    Jian-Tao Wang; Yu Zhang; Qing Liu; Qiang He; Dong-Liang Zhang; Ying Zhang; Ji-Xuan Xiao

    2015-01-01

    Purpose:To determine the effect of the posterior condylar offset (PCO) on clinical results after total knee arthroplasty (TKA) using a high-flex posterior-stabilized (PS) fixed-bearing prosthesis.Methods:We prospectively studied the clinical and radiographic materials of 89 consecutive female patients (89 knees),who had undergone primary TKAs for end-stage osteoarthritis.All operations were performed by a single senior surgeon or under his supervision using the same operative technique.Based on the corrected PCO change,we divided all cases into two groups:group A (corrected PCO change ≥0 mm,58 knees) and group B (corrected PCO change <0 mm,31 knees).One-year postoperatively,clinical and radiographic variables from the two groups were compared by independent t-test.The associations between the corrected PCO changes and the improvements of clinical variables in all patients were analyzed by Pearson linear correlation.Results:One-year postoperatively,the Knee Society Scores,the Western Ontario and McMaster Universities Osteoarthritis Index,non-weight-bearing active and passive range of knee flexion,flexion contracture,extensor lag,and their improvements had no statistical differences between the two groups (all p > 0.05).The corrected PCO change was not significantly correlated with the improvement of any clinical variable (all p > 0.05).Group A demonstrated greater flexion than group B during active weight bearing (p < 0.05).Conclusions:Restoration of PCO plays an important role in the optimization of active knee flexion during weight-bearing conditions after posterior-stabilized TKA,while it has no benefit to non-weight-bearing knee flexion or any other clinical result.

  20. Independent measurement of femoral cortical thickness and cortical bone density using clinical CT.

    Science.gov (United States)

    Treece, G M; Gee, A H

    2015-02-01

    The local structure of the proximal femoral cortex is of interest since both fracture risk, and the effects of various interventions aimed at reducing that risk, are associated with cortical properties focused in particular regions rather than dispersed over the whole bone. Much of the femoral cortex is less than 3mm thick, appearing so blurred in clinical CT that its actual density is not apparent in the data, and neither thresholding nor full-width half-maximum techniques are capable of determining its width. Our previous work on cortical bone mapping showed how to produce more accurate estimates of cortical thickness by assuming a fixed value of the cortical density for each hip. However, although cortical density varies much less over the proximal femur than thickness, what little variation there is leads to errors in thickness measurement. In this paper, we develop the cortical bone mapping technique by exploiting local estimates of imaging blur to correct the global density estimate, thus providing a local density estimate as well as more accurate estimates of thickness. We also consider measurement of cortical mass surface density and the density of trabecular bone immediately adjacent to the cortex. Performance is assessed with ex vivo clinical QCT scans of proximal femurs, with true values derived from high resolution HRpQCT scans of the same bones. We demonstrate superior estimation of thickness than is possible with alternative techniques (accuracy 0.12 ± 0.39 mm for cortices in the range 1-3mm), and that local cortical density estimation is feasible for densities >800 mg/cm(3).

  1. Regional vulnerability of longitudinal cortical association connectivity: Associated with structural network topology alterations in preterm children with cerebral palsy.

    Science.gov (United States)

    Ceschin, Rafael; Lee, Vince K; Schmithorst, Vince; Panigrahy, Ashok

    2015-01-01

    Preterm born children with spastic diplegia type of cerebral palsy and white matter injury or periventricular leukomalacia (PVL), are known to have motor, visual and cognitive impairments. Most diffusion tensor imaging (DTI) studies performed in this group have demonstrated widespread abnormalities using averaged deterministic tractography and voxel-based DTI measurements. Little is known about structural network correlates of white matter topography and reorganization in preterm cerebral palsy, despite the availability of new therapies and the need for brain imaging biomarkers. Here, we combined novel post-processing methodology of probabilistic tractography data in this preterm cohort to improve spatial and regional delineation of longitudinal cortical association tract abnormalities using an along-tract approach, and compared these data to structural DTI cortical network topology analysis. DTI images were acquired on 16 preterm children with cerebral palsy (mean age 5.6 ± 4) and 75 healthy controls (mean age 5.7 ± 3.4). Despite mean tract analysis, Tract-Based Spatial Statistics (TBSS) and voxel-based morphometry (VBM) demonstrating diffusely reduced fractional anisotropy (FA) reduction in all white matter tracts, the along-tract analysis improved the detection of regional tract vulnerability. The along-tract map-structural network topology correlates revealed two associations: (1) reduced regional posterior-anterior gradient in FA of the longitudinal visual cortical association tracts (inferior fronto-occipital fasciculus, inferior longitudinal fasciculus, optic radiation, posterior thalamic radiation) correlated with reduced posterior-anterior gradient of intra-regional (nodal efficiency) metrics with relative sparing of frontal and temporal regions; and (2) reduced regional FA within frontal-thalamic-striatal white matter pathways (anterior limb/anterior thalamic radiation, superior longitudinal fasciculus and cortical spinal tract) correlated with

  2. 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

  3. An evaluation of Microleakage of Posterior Composites

    Directory of Open Access Journals (Sweden)

    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.

  4. 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.

  5. Pulmonary hematocele mimicking posterior mediastinal mass : two cases report

    Energy Technology Data Exchange (ETDEWEB)

    Ryu, Dae Sik; Kim, Nam Hyeun; Jung, Seung Mun; Choi, Soo Jung; Wo, Don Hee; Kim, Jong Ook; Park, Chong Bin; Park, Man Soo [Asan foundation. Kangneung Hospital, Seoul (Korea, Republic of)

    1998-08-01

    Closed chest trauma occasionally results in the development of traumatic lung cyst or pulmonary hematocele.Radiologically, this latter rarely mimics posterior mediastinal mass, which can cause unnecessary surgical resection, We encountered two cases of pulmonary hematocele simulating posterior mediastinal mass. Multiplicity of the lesion, fracture of surrounding bony structure, decrease of mass size at follow-up examination, an acute angle between the mass and chest wall, peripheral rim enhancement of the mass, as seen on CT scans, or characteristic signal intensity suggesting hematoma, as seen on MR images, helped differentiate pulmonary hematocele from posterior mediastinal mass.

  6. Cortical correlates of acquired deafness to dissonance.

    Science.gov (United States)

    Brattico, Elvira; Tervaniemi, Mari; Valimaki, Vesa; Van Zuijen, Titia; Peretz, Isabelle

    2003-11-01

    Patient I.R., who had bilateral lesions in the auditory cortex but intact hearing, did not distinguish dissonant from consonant musical excerpts in behavioral testing. We additionally found that the electrical brain responses did not differentiate musical intervals in terms of their dissonance/consonance, consistent with the idea that this phenomenon depends on the integrity of cortical functions.

  7. A case of cortical deafness and anarthria.

    Science.gov (United States)

    Kaga, Kimitaka; Nakamura, Masako; Takayama, Yoshihiro; Momose, Hiromitsu

    2004-03-01

    Generally, cortical deafness is not complicated by anarthria and cortical anarthria does not affect auditory perception. We report a case of simultaneous progressive cortical deafness and anarthria. At the age of 70 years, the patient, a woman, noticed hearing problems when using the telephone, which worsened rapidly over the next 2 years. She was then referred to our hospital for further examinations of her hearing problems. Auditory tests revealed threshold elevation in the low and middle frequencies on pure-tone audiometry, a maximum speech discrimination of 25% and normal otoacoustic emissions and auditory brainstem, middle- and long-latency responses. An articulation test revealed abnormal pronunciation. Because of these problems only written and not verbal communication was possible; her ability to read and write was unimpaired. She showed no other neurological problems. Brain MRI demonstrated atrophic changes of the auditory cortex and Wernicke's language center and PET suggested low uptake of (18F) 2-fluoro-2-deoxy-d-glucose around the Sylvian fissures in both hemispheres. Neurologically, the patient was suspected of having progressive aphasia or frontotemporal dementia. Her cortical deafness and anarthria are believed to be early signs of this entity.

  8. Prenatal Alcohol Exposure and Cortical Angiogenesis

    Directory of Open Access Journals (Sweden)

    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. Osteocyte lacunar properties in rat cortical bone

    DEFF Research Database (Denmark)

    Bach-Gansmo, Fiona Linnea; Weaver, James C.; Jensen, Mads Hartmann;

    2015-01-01

    -species but also inter-site variation in lacunar properties. Here, osteocyte lacunae in rat cortical bone have been studied using synchrotron radiation micro computed tomography (SR μCT) and backscattered electron (BE) microscopy. Quantitative lacunar geometric characteristics are reported based on the synchrotron...

  10. Cortical source localization of infant cognition.

    Science.gov (United States)

    Reynolds, Greg D; Richards, John E

    2009-01-01

    Neuroimaging techniques such as positron emission topography (PET) and functional magnetic resonance imaging (fMRI) have been utilized with older children and adults to identify cortical sources of perceptual and cognitive processes. However, due to practical and ethical concerns, these techniques cannot be routinely applied to infant participants. An alternative to such neuroimaging techniques appropriate for use with infant participants is high-density electroencephalogram (EEG) recording and cortical source localization techniques. The current article provides an overview of a method developed for such analyses. The method consists of four steps: (1) recording high-density (e.g., 128-channel) EEG. (2) Analysis of individual participant raw segmented data with independent component analysis (ICA). (3) Estimation of equivalent current dipoles (ECDs) that represent cortical sources for the observed ICA component clusters. (4) Calculation of component activations in relation to experimental factors. We discuss an example of research applying this technique to investigate the development of visual attention and recognition memory. We also describe the application of "realistic head modeling" to address some of the current limitations of infant cortical source localization.

  11. A revised view of sensory cortical parcellation

    Science.gov (United States)

    Wallace, Mark T.; Ramachandran, Ramnarayan; Stein, Barry E.

    2004-01-01

    Traditional cortical parcellation schemes have emphasized the presence of sharply defined visual, auditory, and somatosensory domains populated exclusively by modality-specific neurons (i.e., neurons responsive to sensory stimuli from a single sensory modality). However, the modality-exclusivity of this scheme has recently been challenged. Observations in a variety of species suggest that each of these domains is subject to influences from other senses. Using the cerebral cortex of the rat as a model, the present study systematically examined the capability of individual neurons in visual, auditory, and somatosensory cortex to be activated by stimuli from other senses. Within the major modality-specific domains, the incidence of inappropriate (i.e., nonmatching) and/or multisensory neurons was very low. However, at the borders between each of these domains a concentration of multisensory neurons was found whose modality profile matched the representations in neighboring cortices and that were able to integrate their cross-modal inputs to give rise to enhanced and/or depressed responses. The results of these studies are consistent with some features of both the traditional and challenging views of cortical organization, and they suggest a parcellation scheme in which modality-specific cortical domains are separated from one another by transitional multisensory zones. PMID:14766982

  12. Malformations of cortical development and neocortical focus.

    Science.gov (United States)

    Luhmann, Heiko J; Kilb, Werner; Clusmann, Hans

    2014-01-01

    Developmental neocortical malformations resulting from abnormal neurogenesis, disturbances in programmed cell death, or neuronal migration disorders may cause a long-term hyperexcitability. Early generated Cajal-Retzius and subplate neurons play important roles in transient cortical circuits, and structural/functional disorders in early cortical development may induce persistent network disturbances and epileptic disorders. In particular, depolarizing GABAergic responses are important for the regulation of neurodevelopmental events, like neurogenesis or migration, while pathophysiological alterations in chloride homeostasis may cause epileptic activity. Although modern imaging techniques may provide an estimate of the structural lesion, the site and extent of the cortical malformation may not correlate with the epileptogenic zone. The neocortical focus may be surrounded by widespread molecular, structural, and functional disturbances, which are difficult to recognize with imaging technologies. However, modern imaging and electrophysiological techniques enable focused hypotheses of the neocortical epileptogenic zone, thus allowing more specific epilepsy surgery. Focal cortical malformation can be successfully removed with minimal rim, close to or even within eloquent cortex with a promising risk-benefit ratio.

  13. 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

  14. Thalamic posterior ventral neurons with bifurcating axons to the first and second somatosensory areas in the cat, demonstrated by the fluorescent retrograde double labeling technique.

    Directory of Open Access Journals (Sweden)

    Yanagihara,Mamoru

    1987-12-01

    Full Text Available The thalamic posterior ventral neurons with bifurcating axons to both the first and second somatosensory cortical areas (SI and SII in the cat were examined by the fluorescent retrograde double labeling technique. After injection of Evans blue (EB into the SI, and of 4',6-diamidino-2-phenylindol.2HCl (DAPI into the SII of the same hemisphere, EB- and DAPI-labeled cells were observed predominantly in both the posterolateral ventral and the posteromedial ventral nuclei of the thalamus. Although EB single-labeled and DAPI single-labeled cells tended to occupy separate regions within the posterior ventral nuclei, a small number of cells double-labeled with both EB and DAPI were detected in the border zone between two single-labeled cell groups. These observations indicate that some cells in the posteromedial and posterolateral ventral nuclei project both to the SI and SII by bifurcating axons.

  15. Cortical inactivation by cooling in small animals

    Directory of Open Access Journals (Sweden)

    Ben eCoomber

    2011-06-01

    Full Text Available Reversible inactivation of the cortex by surface cooling is a powerful method for studying the function of a particular area. Implanted cooling cryoloops have been used to study the role of individual cortical areas in auditory processing of awake-behaving cats. Cryoloops have also been used in rodents for reversible inactivation of the cortex, but recently there has been a concern that the cryoloop may also cool non-cortical structures either directly or via the perfusion of blood, cooled as it passed close to the cooling loop. In this study we have confirmed that the loop can inactivate most of the auditory cortex without causing a significant reduction in temperature of the auditory thalamus or other sub-cortical structures. We placed a cryoloop on the surface of the guinea pig cortex, cooled it to 2°C and measured thermal gradients across the neocortical surface. We found that the temperature dropped to 20-24°C among cells within a radius of about 2.5mm away from the loop. This temperature drop was sufficient to reduce activity of most cortical cells and led to the inactivation of almost the entire auditory region. When the temperature of thalamus, midbrain, and middle ear were measured directly during cortical cooling, there was a small drop in temperature (about 4°C but this was not sufficient to directly reduce neural activity. In an effort to visualise the extent of neural inactivation we measured the uptake of thallium ions following an intravenous injection. This confirmed that there was a large reduction of activity across much of the ipsilateral cortex and only a small reduction in subcortical structures.

  16. Cortical excitability changes following grasping exercise augmented with electrical stimulation

    DEFF Research Database (Denmark)

    Barsi, Gergely Istvan; Popovic, Dejan B.; Tarkka, Ina M.

    2008-01-01

    Rehabilitation with augmented electrical stimulation can enhance functional recovery after stroke, and cortical plasticity may play a role in this process. The purpose of this study was to compare the effects of three training paradigms on cortical excitability in healthy subjects. Cortical excit...

  17. 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...

  18. 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.).

  19. Modified posterior vertebral column resection for Kümmell disease

    Science.gov (United States)

    Liu, Feng-Yu; Huo, Li-Shuang; Liu, Sen; Wang, Hui; Zhang, Li-Jun; Yang, Da-Long; Ding, Wen-Yuan

    2017-01-01

    Abstract Rationale: Kümmell's disease is defined as delayed traumatic vertebral collapse disease in which patients develop a kyphosis after asymptomatic minor spinal trauma. Both anterior approach and posterior approach have been reported, however, there is no standard treatment for Kümmell's disease. Patient concerns: We described a successful modified posterior vertebral column resection in a patient with Kümmell's disease. A 65-year-old woman reported persistent back pain for almost three months. Diagnoses: Kümmell's disease was diagnosed based on computer tomography (CT) and magnetic resonance imaging (MRI). Interventions: Modified posterior vertebral column resection combined with short-segment fixation was designed to treat this disease. Outcomes: The procedure was successful without any complications. Patient reported that symptoms were obviously improved in one week after operation. Lessons: Modified posterior vertebral column resection combined with short-segment fixation is an effective treatment option for Kümmell's disease. PMID:28151882

  20. Pins, dowels, and other retentive devices in posterior teeth.

    Science.gov (United States)

    Jacobi, R; Shillingburg, H T

    1993-07-01

    Devices used to increase retention of restorations to severely damaged posterior teeth are described, with an emphasis on pins and dowels. Advantages and disadvantages of different techniques and measures to help prevent and correct problems are presented.

  1. 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

  2. Complete posterior migration of intact vertebral body in spinal tuberculosis

    Directory of Open Access Journals (Sweden)

    Sridhar Krishnamurthy

    2009-01-01

    Full Text Available Spinal tuberculosis most commonly presents as a paradiscal lesion involving the disc space and adjacent vertebral bodies. Atypical forms of spinal tuberculosis have been described and are most often a result of posterior element involvement. The authors report a patient, who presented with complete posterior migration of an intact vertebral body, a complication of spinal tuberculosis that has not been reported till date. A 12-year-old girl with history of pulmonary tuberculosis presented with progressive paraparesis and back pain. Plain X-rays and MRI revealed that the L2 vertebral body had migrated posteriorly into the spinal canal, without significant movement of the posterior elements. The vertebral body was normal, with no erosion or bone loss. However, bilateral pedicle and facet joint involvement was seen. The neural elements were decompressed through an anterolateral retroperitoneal approach and the spine reconstructed. The authors present this rare manifestation of spinal tuberculosis and discuss the possible mechanisms of this presentation.

  3. PHACE syndrome in antenatally diagnosed posterior fossa anomaly

    Directory of Open Access Journals (Sweden)

    Seema Pavaman Sindgikar

    2014-01-01

    Full Text Available PHACE is a neurocutaneous syndrome, an acronym to describe patients with facial segmental hemangiomas and other malformations. We describe a newborn antenatally diagnosed to have posterior fossa anomaly and subsequently as PHACE syndrome.

  4. Techniques for posterior lamellar keratoplasty through a scleral incision

    NARCIS (Netherlands)

    Melles, GRJ; Kamminga, N

    2003-01-01

    Purpose. To describe several techniques for posterior lamellar keratoplasty through a scleral incision, for management of corneal endothelial disorders like pseudophacic bullous keratopathy and Fuchs' endothelial dystrophy, and to report the mid-term clinical results. Methods. Three techniques have

  5. Current management of posterior wall fractures of the acetabulum.

    Science.gov (United States)

    Moed, Berton R; Kregor, Philip J; Reilly, Mark C; Stover, Michael D; Vrahas, Mark S

    2015-01-01

    The general goals for treating an acetabular fracture are to restore congruity and stability of the hip joint. These goals are no different from those for the subset of fractures of the posterior wall. Nevertheless, posterior wall fractures present unique problems compared with other types of acetabular fractures. Successful treatment of these fractures depends on a multitude of factors. The physician must understand their distinctive radiologic features, in conjunction with patient factors, to determine the appropriate treatment. By knowing the important points of posterior surgical approaches to the hip, particularly the posterior wall, specific techniques can be used for fracture reduction and fixation in these often challenging fractures. In addition, it is important to develop a complete grasp of potential complications and their treatment. The evaluation and treatment protocols initially developed by Letournel and Judet continue to be important; however, the surgeon also should be aware of new information published and presented in the past decade.

  6. 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.

  7. Properties of bilateral spinocerebellar activation of cerebellar cortical neurons

    Directory of Open Access Journals (Sweden)

    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. Brainstem variant of posterior reversible encephalopathy syndrome: A case report.

    Science.gov (United States)

    Tortora, Fabio; Caranci, Ferdinando; Belfiore, Maria Paola; Manzi, Francesca; Pagliano, Pasquale; Cirillo, Sossio

    2015-12-01

    Posterior reversible encephalopathy syndrome (PRES) is a clinico-radiological condition, generally observed in conjunction with severe and acute hypertension, that involves mainly the posterior head areas (occipital and temporal lobes) and anterior "watershed" areas. In this syndrome it is rare to observe a predominant involvement of the brainstem. We describe the clinical and radiological findings in a patient with brainstem involvement, discussing its pathophysiological features and possible differential diagnosis.

  9. Triple procedure in posterior segment intraocular foreign body

    Directory of Open Access Journals (Sweden)

    Azad Rajvardhan

    1998-01-01

    Full Text Available Three patients with intraocular foreign bodies and traumatic cataracts underwent single stage pars plana lensectomy with anterior capsule preservation, vitrectomy, removal of the foreign body, and intraocular lens implantation. The preserved anterior capsule permitted support for the placement of an intraocular lens in the posterior chamber in the ciliary sulcus. The procedure enabled early visual rehabilitation. This procedure seems useful in the management of posterior segment intraocular foreign body associated with cataract.

  10. 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.

  11. Mature posterior fossa teratoma mimicking infratentorial meningioma: a case report.

    Science.gov (United States)

    Coulibaly, O; El Kacemi, I; Fatemi, N; Gana, R; Saïdi, A; Maaqili, R; Jiddane, M; Bellakhdar, F

    2012-02-01

    Intracranial teratomas are congenital neoplasms mostly diagnosed in the pediatric hood and usually involve supratentorial midline structures. These teratomas, especially those involving the posterior fossa are an uncommon and representing less than 0.5% of all intracranial tumors. We report a case of mature posterior fossa teratoma in an adult patient diagnosed in the 4th decade of life. This lesion was taken for a huge infratentorial meningioma.

  12. Posterior Chamber IOL Implantation in Traumatic Cataract with Injured Complications

    Institute of Scientific and Technical Information of China (English)

    1992-01-01

    Twenty-five cases of posterior chamber IOL implantation intraumatic cataract with complications associated with primary injury werereported.The operating methods were described and the post-operative com-plications were discussed.Seventy-two percent of patients have the correctvision over 20/40.It is suggested that the posterior chamber IOL can be im-planted in traumatic cataract with some injured complications.EYE SCIENCE1992;8:111-112.

  13. Double bundle posterior cruciate ligament reconstruction: surgical technique and results.

    Science.gov (United States)

    Fanelli, Gregory C; Beck, John D; Edson, Craig J

    2010-12-01

    The keys to successful posterior cruciate ligament reconstruction are to identify and treat all pathology, use strong graft material, accurately place tunnels in anatomic insertion sites, minimize graft bending, use a mechanical graft tensioning device, use primary and back-up graft fixation, and use the appropriate postoperative rehabilitation program. Adherence to these technical principles results in successful single and double-bundle arthroscopic transtibial tunnel posterior cruciate ligament reconstruction based upon stress radiography, arthrometer, knee ligament rating scales, and patient satisfaction measurements.

  14. Patient adaptable cerebellar retractor system: Use in posterior fossa surgery

    Directory of Open Access Journals (Sweden)

    Hamid Borghei-Razavi

    2015-06-01

    Full Text Available A new patient adaptable dual use soft tissue spreader and cerebellar retractor system designed for use during surgery of the posterior fossa is described. We found that this new retractor design allowed for excellent exposure, plus greater freedom and dexterity during the posterior fossa surgery. This novel instrument is an improvement over the existing instrument, because it provided more force/power transmission from pins/connectors to the brain spatula via the shorter flexible arm.

  15. 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.

  16. 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.

  17. 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.

  18. Cortical subarachnoid hemorrhage associated with reversible cerebral vasoconstriction syndrome after elective triplet cesarean delivery.

    Science.gov (United States)

    Albano, Beatrice; Del Sette, Massimo; Roccatagliata, Luca; Gandolfo, Carlo; Primavera, Alberto

    2011-06-01

    Reversible cerebral vasoconstriction syndromes (RCVS) comprise a group of disorders characterized by prolonged, but reversible vasoconstriction of the cerebral arteries, usually associated with acute-onset, severe, recurrent headaches, with or without additional neurological signs and symptoms. Various complications of this condition have been observed, such as cortical subarachnoid hemorrhages (cSAH), intracerebral hemorrhages, reversible posterior leukoencephalopathy, ischaemic strokes and transient ischaemic attacks. It is important to include RCVS in thunderclap headache differential diagnosis and among non-aneurismatic subarachnoid hemorrhage causes. In the past years, thanks to the major diffusion of new diagnostic tools such as magnetic resonance, computed tomography and digital subtraction angiography, RCVS have been demonstrated to be more frequent than previously thought. We report an illustrative case of a woman affected by a small cSAH, associated to RCVS, after elective triplet cesarean delivery. To our knowledge, this is the first case of cSAH associated to RCVS after a triplet pregnancy.

  19. Cortical neuroplastic changes to painful colon stimulation in patients with irritable bowel syndrome.

    Science.gov (United States)

    Drewes, Asbjørn Mohr; Rössel, Petra; Le Pera, Domenica; Arendt-Nielsen, Lars; Valeriani, Massimiliano

    2005-03-03

    The aim of this study was to model the cerebral generators following painful electrical stimulation of the sigmoid colon in 10 healthy controls and 10 patients with visceral pain due to the irritable bowel syndrome. The evoked brain potentials to 30 painful electrical stimuli from the sigmoid colon were recorded from 31 surface electrodes and subjected to electrical dipole source modelling. Two dipoles in the bilateral insular cortex, one dipole in the anterior cingulate gyrus and two dipoles in the bilateral second somatosensory area were found. The anterior cingulate dipole showed a more posterior position in patients than in control subjects. This finding suggests that the cortical representation of painful stimuli can be modified in presence of chronic visceral pain and that this change involves the anterior cingulate gyrus.

  20. Capsaicin failed in suppressing cortical processing of CO2 laser pain in migraine patients.

    Science.gov (United States)

    de Tommaso, Marina; Losito, Luciana; Difruscolo, Olimpia; Sardaro, Michele; Libro, Giuseppe; Guido, Marco; Lamberti, Paolo; Livrea, Paolo

    The aim of this study was to compare the properties of the nociceptive system in eight migraine without aura patients in the pain-free phase with 10 healthy controls, by evaluating the topography and the source of the CO2 laser-evoked potentials (LEPs) obtained by the right supraorbital skin, during and after capsaicin topical application. In healthy subjects the acute cutaneous pain induced by capsaicin reduced the amplitude of the vertex LEPs and induced a posterior shifting of the P2 wave dipolar source within the anterior cingulate cortex. These functional changes seemed significantly reduced in migraine patients, for a disturbed pattern of pain modulation at the cortical level, which may subtend the onset and persistence of migraine.

  1. Studies on the cortical morphogenesis during cell division in Halteria grandinella (Muller, 1773) (Ciliophora, Oligotrichida)

    Science.gov (United States)

    Song, Weibo

    1993-06-01

    Morphogenesis during cell division was investigated in oligotrichous ciliate, Halteria grandinella utilizing protargol impregnated specimens. The cortical morphogenetical pattern of Halteria grandinella is generally similar to that given by Fauré-Fremiet. The proter inherits the parental adoral zone of membranelles (AZM) apparently unchanged; in the opisthe the oral primordium develops de novo from a single. AZM-anlage; somatic cirri for both the proter and opisthe are separately differentiated from 10 (seldom 9) cirral primordia that originate de novo from 10 latitudinal developmental analagen. The anlage of paroral membrane of opisthe forms just to the right of the posterior end of the oral primordium. Each streak of cirral primordia develops 4 groups of basal body pairs: both of the anterior two consist of only one pair of basal bodies, on the contrary, each of the last two groups has 2 basal body pairs.

  2. One step arthroscopically assisted Latarjet and posterior bone-block, for recurrent posterior instability and anterior traumatic dislocation

    Science.gov (United States)

    D’Ambrosi, Riccardo; Perfetti, Carlo; Garavaglia, Guido; Taverna, Ettore

    2015-01-01

    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. PMID:26288539

  3. One step arthroscopically assisted Latarjet and posterior bone-block, for recurrent posterior instability and anterior traumatic dislocation.

    Science.gov (United States)

    D'Ambrosi, Riccardo; Perfetti, Carlo; Garavaglia, Guido; Taverna, Ettore

    2015-01-01

    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.

  4. 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.

  5. Serotonin modulation of cortical neurons and networks

    Directory of Open Access Journals (Sweden)

    Pau eCelada

    2013-04-01

    Full Text Available The serotonergic pathways originating in the dorsal and median raphe nuclei (DR and MnR, respectively are critically involved in cortical function. Serotonin (5-HT, acting on postsynaptic and presynaptic receptors, is involved in cognition, mood, impulse control and motor functions by 1 modulating the activity of different neuronal types, and 2 varying the release of other neurotransmitters, such as glutamate, GABA, acetylcholine and dopamine. Also, 5-HT seems to play an important role in cortical development. Of all cortical regions, the frontal lobe is the area most enriched in serotonergic axons and 5-HT receptors. 5-HT and selective receptor agonists modulate the excitability of cortical neurons and their discharge rate through the activation of several receptor subtypes, of which the 5-HT1A, 5-HT1B, 5-HT2A and 5-HT3 subtypes play a major role. Little is known, however, on the role of other excitatory receptors moderately expressed in cortical areas, such as 5-HT2C, 5-HT4, 5-HT6 and 5-HT7. In vitro and in vivo studies suggest that 5-HT1A and 5-HT2A receptors are key players and exert opposite effects on the activity of pyramidal neurons in the medial prefrontal cortex (mPFC. The activation of 5-HT1A receptors in mPFC hyperpolarizes pyramidal neurons whereas that of 5-HT2A receptors results in neuronal depolarization, reduction of the afterhyperpolarization and increase of excitatory postsynaptic currents (EPSCs and of discharge rate. 5-HT can also stimulate excitatory (5-HT2A and 5-HT3 and inhibitory (5-HT1A receptors in GABA interneurons to modulate synaptic GABA inputs onto pyramidal neurons. Likewise, the pharmacological manipulation of various 5-HT receptors alters oscillatory activity in PFC, suggesting that 5-HT is also involved in the control of cortical network activity. A better understanding of the actions of 5-HT in PFC may help to develop treatments for mood and cognitive disorders associated with an abnormal function of the

  6. 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.

  7. Eclamptogenic Gerstmann's syndrome in combination with cortical agnosia and cortical diplopia.

    Science.gov (United States)

    Käsmann, B; Ruprecht, K W

    1995-07-01

    Cortical blindness is defined as a loss of vision due to bilateral retrogeniculate lesions (geniculocalcarine blindness). Gerstmann's syndrome is a combination of disorientation for left and right, finger agnosia, and profound agraphia, alexia, and acalculia. It is due to a lesion in the left angular gyrus, situated at the confluence of the temporal, parietal, and occipital lobes. We report on a patient who suffered from severe underdiagnosed eclampsia and who developed bilateral extensive medial temporal, parietal, and calcarine ischemic infarctions during an eclamptic fit. In addition, ischemia destroyed the left angular gyrus. The combination of these lesions led to Gerstmann's syndrome with additional cortical agnosia and cortical diplopia. For the first few months following the ischemic insult, the patient had been cortically blind. Thereafter, the patient slowly regained a visual acuity of 0.1 in both eyes. She then experienced monocular and binocular diplopia. Her ocular motility was normal; there was no phoria or tropia. Monocular and binocular diplopia slowly became less severe over the following year. Now, 2 years after the incident, the patient has a visual acuity of 0.2 in both eyes and no double vision. However, the handicapping symptoms of Gerstmann's syndrome, which make leading a normal life impossible, have persisted--the patient still cannot cope alone, mainly due to the severe disorientation for left and right. The picture of cortical agnosia, cortical diplopia, and Gerstmann's syndrome is a very rare combination. Visual recovery and rehabilitation in cortical blindness are severely affected and made difficult by the symptoms of Gerstmann's syndrome. In our case the reason for such a dramatic clinical picture was eclampsia, whose prodomes had not been diagnosed in time.

  8. Control and amplification of cortical neurodynamics

    Science.gov (United States)

    Liljenstroem, Hans; Aronsson, P.

    1999-03-01

    We investigate different mechanisms for the control and amplification of cortical neurodynamics, using a neural network model of a three layered cortical structure. We show that different dynamical states can be obtained by changing a control parameter of the input-output relation, or by changing the noise level. Point attractor, limit cycle, and strange attractor dynamics occur at different values of the control parameter. For certain, optimal noise levels, system performance is maximized, analogous to stochastic resonance phenomena. Noise can also be used to induce different dynamical states. A few noisy network units distributed in a network layer can result in global synchronous oscillations, or waves of activity moving across the network. We further demonstrate that fast synchronization of network activity can be obtained by implementing electromagnetic interactions between network units.

  9. 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...

  10. Perceptual incongruence influences bistability and cortical activation.

    Directory of Open Access Journals (Sweden)

    Gijs Joost Brouwer

    Full Text Available We employed a parametric psychophysical design in combination with functional imaging to examine the influence of metric changes in perceptual incongruence on perceptual alternation rates and cortical responses. Subjects viewed a bistable stimulus defined by incongruent depth cues; bistability resulted from incongruence between binocular disparity and monocular perspective cues that specify different slants (slant rivalry. Psychophysical results revealed that perceptual alternation rates were positively correlated with the degree of perceived incongruence. Functional imaging revealed systematic increases in activity that paralleled the psychophysical results within anterior intraparietal sulcus, prior to the onset of perceptual alternations. We suggest that this cortical activity predicts the frequency of subsequent alternations, implying a putative causal role for these areas in initiating bistable perception. In contrast, areas implicated in form and depth processing (LOC and V3A were sensitive to the degree of slant, but failed to show increases in activity when these cues were in conflict.

  11. Extensive cortical involvement in leptomeningeal carcinomatosis.

    Science.gov (United States)

    Ayzenberg, I; Börnke, C; Tönnes, C; Ziebarth, W; Lavrov, A; Lukas, C

    2012-12-01

    We present a 77-year-old previously well patient with facial asymmetry and progressive weakness of the lower extremities. An initial MRI revealed slight contrast enhancement of the meninges. Three consecutive cerebrospinal fluid examinations demonstrated low glucose concentration, marked elevation of total protein and moderate pleocytosis. No tumor cells, fungi, acid-fast bacilli or mycobacterial DNA were found. The patient's level of consciousness deteriorated dramatically, and follow-up MRI showed widespread extensive cortical hyperintensities. The lesions showed restricted diffusion on diffusion-weighted images as well as low values on the corresponding apparent diffusion coefficient maps, the changes consistent with diffuse cytotoxic edema. Neuropathological examination findings were of leptomeningeal carcinomatosis (LMC) with diffuse continuous infiltration of the cerebral cortex, cerebellum and spinal cord. The autopsy revealed a subcentimetre adenocarcinoma of the lung. To our knowledge, this is the first report demonstrating extensive cortical involvement in adenocarcinomatous LMC.

  12. Massive cortical reorganization in sighted Braille readers.

    Science.gov (United States)

    Siuda-Krzywicka, Katarzyna; Bola, Łukasz; Paplińska, Małgorzata; Sumera, Ewa; Jednoróg, Katarzyna; Marchewka, Artur; Śliwińska, Magdalena W; Amedi, Amir; Szwed, Marcin

    2016-03-15

    The brain is capable of large-scale reorganization in blindness or after massive injury. Such reorganization crosses the division into separate sensory cortices (visual, somatosensory...). As its result, the visual cortex of the blind becomes active during tactile Braille reading. Although the possibility of such reorganization in the normal, adult brain has been raised, definitive evidence has been lacking. Here, we demonstrate such extensive reorganization in normal, sighted adults who learned Braille while their brain activity was investigated with fMRI and transcranial magnetic stimulation (TMS). Subjects showed enhanced activity for tactile reading in the visual cortex, including the visual word form area (VWFA) that was modulated by their Braille reading speed and strengthened resting-state connectivity between visual and somatosensory cortices. Moreover, TMS disruption of VWFA activity decreased their tactile reading accuracy. Our results indicate that large-scale reorganization is a viable mechanism recruited when learning complex skills.

  13. Relearning to See in Cortical Blindness.

    Science.gov (United States)

    Melnick, Michael D; Tadin, Duje; Huxlin, Krystel R

    2016-04-01

    The incidence of cortically induced blindness is increasing as our population ages. The major cause of cortically induced blindness is stroke affecting the primary visual cortex. While the impact of this form of vision loss is devastating to quality of life, the development of principled, effective rehabilitation strategies for this condition lags far behind those used to treat motor stroke victims. Here we summarize recent developments in the still emerging field of visual restitution therapy, and compare the relative effectiveness of different approaches. We also draw insights into the properties of recovered vision, its limitations and likely neural substrates. We hope that these insights will guide future research and bring us closer to the goal of providing much-needed rehabilitation solutions for this patient population.

  14. 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

  15. 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

  16. Motor cortical function and the precision grip.

    Science.gov (United States)

    Geevasinga, Nimeshan; Menon, Parvathi; Kiernan, Matthew C; Vucic, Steve

    2014-12-01

    While task-dependent changes in motor cortical outputs have been previously reported, the issue of whether such changes are specific for complex hand tasks remains unresolved. The aim of the present study was to determine whether cortical inhibitory tone and cortical output were greater during precision grip and power grip. Motor cortex excitability was undertaken by using the transcranial magnetic stimulation threshold tracking technique in 15 healthy subjects. The motor-evoked potential (MEP) responses were recorded over the abductor pollicis brevis (APB), with the hand in the following positions: (1) rest, (2) precision grip and (3) power grip. The MEP amplitude (MEP amplitude REST 23.6 ± 3.3%; MEP amplitude PRECISION GRIP 35.2 ± 5.6%; MEP amplitude POWER GRIP 19.6 ± 3.4%, F = 2.4, P < 0.001) and stimulus-response gradient (SLOPEREST 0.06 ± 0.01; SLOPEPRCISION GRIP 0.15 ± 0.04; SLOPE POWER GRIP 0.07 ± 0.01, P < 0.05) were significantly increased during precision grip. Short interval intracortical inhibition (SICI) was significantly reduced during the precision grip (SICI REST 15.0 ± 2.3%; SICI PRECISION GRIP 9.7 ± 1.5%, SICI POWER GRIP 15.9 ± 2.7%, F = 2.6, P < 0.05). The present study suggests that changes in motor cortex excitability are specific for precision grip, with functional coupling of descending corticospinal pathways controlling thumb and finger movements potentially forming the basis of these cortical changes.

  17. Motor cortical plasticity in Parkinson's disease.

    Science.gov (United States)

    Udupa, Kaviraja; Chen, Robert

    2013-09-04

    In Parkinson's disease (PD), there are alterations of the basal ganglia (BG) thalamocortical networks, primarily due to degeneration of nigrostriatal dopaminergic neurons. These changes in subcortical networks lead to plastic changes in primary motor cortex (M1), which mediates cortical motor output and is a potential target for treatment of PD. Studies investigating the motor cortical plasticity using non-invasive transcranial magnetic stimulation (TMS) have found altered plasticity in PD, but there are inconsistencies among these studies. This is likely because plasticity depends on many factors such as the extent of dopaminergic loss and disease severity, response to dopaminergic replacement therapies, development of l-DOPA-induced dyskinesias (LID), the plasticity protocol used, medication, and stimulation status in patients treated with deep brain stimulation (DBS). The influences of LID and DBS on BG and M1 plasticity have been explored in animal models and in PD patients. In addition, many other factors such age, genetic factors (e.g., brain derived neurotropic factor and other neurotransmitters or receptors polymorphism), emotional state, time of the day, physical fitness have been documented to play role in the extent of plasticity induced by TMS in human studies. In this review, we summarize the studies that investigated M1 plasticity in PD and demonstrate how these afore-mentioned factors affect motor cortical plasticity in PD. We conclude that it is important to consider the clinical, demographic, and technical factors that influence various plasticity protocols while developing these protocols as diagnostic or prognostic tools in PD. We also discuss how the modulation of cortical excitability and the plasticity with these non-invasive brain stimulation techniques facilitate the understanding of the pathophysiology of PD and help design potential therapeutic possibilities in this disorder.

  18. 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.

  19. 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

  20. 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

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    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.

  1. Neurochemical, morphologic, and laminar characterization of cortical projection neurons in the cingulate motor areas of the macaque monkey

    Science.gov (United States)

    Nimchinsky, E. A.; Hof, P. R.; Young, W. G.; Morrison, J. H.; Bloom, F. E. (Principal Investigator)

    1996-01-01

    The primate cingulate gyrus contains multiple cortical areas that can be distinguished by several neurochemical features, including the distribution of neurofilament protein-enriched pyramidal neurons. In addition, connectivity and functional properties indicate that there are multiple motor areas in the cortex lining the cingulate sulcus. These motor areas were targeted for analysis of potential interactions among regional specialization, connectivity, and cellular characteristics such as neurochemical profile and morphology. Specifically, intracortical injections of retrogradely transported dyes and intracellular injection were combined with immunocytochemistry to investigate neurons projecting from the cingulate motor areas to the putative forelimb region of the primary motor cortex, area M1. Two separate groups of neurons projecting to area M1 emanated from the cingulate sulcus, one anterior and one posterior, both of which furnished commissural and ipsilateral connections with area M1. The primary difference between the two populations was laminar origin, with the anterior projection originating largely in deep layers, and the posterior projection taking origin equally in superficial and deep layers. With regard to cellular morphology, the anterior projection exhibited more morphologic diversity than the posterior projection. Commissural projections from both anterior and posterior fields originated largely in layer VI. Neurofilament protein distribution was a reliable tool for localizing the two projections and for discriminating between them. Comparable proportions of the two sets of projection neurons contained neurofilament protein, although the density and distribution of the total population of neurofilament protein-enriched neurons was very different in the two subareas of origin. Within a projection, the participating neurons exhibited a high degree of morphologic heterogeneity, and no correlation was observed between somatodendritic morphology and

  2. Transient cortical blindness after coronary artery angiography.

    Science.gov (United States)

    Terlecki, Michał; Wojciechowska, Wiktoria; Rajzer, Marek; Jurczyszyn, Artur; Bazan-Socha, Stanisława; Bryniarski, Leszek; Czarnecka, Danuta

    2013-01-01

    Coronary angiography is the current gold standard for the diagnosis of ischemic heart disease and therefore the prevalence of percutaneous coronary procedures such as angiography and angioplasty is high. The occurrence of cerebral complications after coronary angiography and coronary angioplasty is low and it mainly includes transient ischemic attack and stroke. The prevalence of transient cortical blindness after X-ray contrast media is low and it is usually seen after cerebral angiography. Until now only a few cases of transient cortical blindness have been described after coronary artery angiography. Regarding the spread of coronary angiography worldwide and in Poland this complication is uniquely rare. A 32-year-old man with multiple extrasystolic ventricular arrhythmia suggesting Brugada syndrome diagnosis according to morphology of the left bundle branch block and with decreased left ventricular ejection fraction was admitted to the First Department of Cardiology and Hypertension, Medical College of the Jagiellonian University in Krakow. Coronary angiography was performed in order to exclude ischemic etiology of the observed abnormalities. No arteriosclerotic lesions were found in coronary arteries. Transient cortical blindness was observed directly after angiography which may have been caused by the neurotoxic effect of the used X-ray contrast medium. In ophthalmologic and neurologic examination as well as in the cerebral computed tomography scan no pathologies were found. Visual impairment disappeared totally within several hours.

  3. Functional rehabilitation of partial cortical blindness?

    Science.gov (United States)

    Stoerig, Petra

    2008-01-01

    The current doctrine regards fields of partial cortical blindness as permanent once a temporally restricted window for spontaneous recovery has passed. Accordingly, neuropsychological rehabilitation mainly applies compensatory procedures that train patients to make better use of their sighted field. The more ambitious goal of functional recovery depends on the survival of pathways that continue to transmit retinal information from the blind field. Although wide-spread antero- and retrograde degeneration follows lesions that destroy or denervate the primary visual cortex and cause partial cortical blindness, several retinofugal pathways survive in cats, monkeys, and humans. In all three species, they subserve a variety of visual functions which develop and improve with practice. Post lesion plasticity is greater when the lesion occurs early in life, but changes in behavioural performance and brain responses have also been demonstrated in late lesion subjects. Although the extent of functional improvement is variable, and the most effective approaches still need to be established across cohorts, the evidence for perceptual learning in fields of cortical blindness indicates that the visual processes mediated by the surviving parts of the visual system can be harnessed to improve functional outcome.

  4. A single posterior approach for multilevel modified vertebral column resection in adults with severe rigid congenital kyphoscoliosis: a retrospective study of 13 cases.

    Science.gov (United States)

    Wang, Yan; Zhang, Yonggang; Zhang, Xuesong; Huang, Peng; Xiao, Songhua; Wang, Zheng; Liu, Zhengsheng; Liu, Baowei; Lu, Ning; Mao, Keya

    2008-03-01

    We report a multilevel modified vertebral column resection (MVCR) through a single posterior approach and clinical outcomes for treatment of severe congenital rigid kyphoscoliosis in adults. Transpedicular eggshell osteotomies and vertebral column resection are two techniques for the surgical treatment of rigid severe spine deformities. The authors developed a new technique combining the two surgical methods as a MVCR, through a single posterior approach, for surgical treatment of severe congenital rigid kyphoscoliosis in adults. Thirteen adult patients with severe rigid congenital kyphoscoliosis deformity were treated by a single posterior approach using a MVCR technique. The surgery processes included a one-stage posterior transpedicular eggshell technique first, and then expanded the eggshell technique to adjacent intervertebra space through abrasive reduction of the vertebral cortices from inside out. All posterior vertebral elements were removed including the cortical vertebral bone around the neural canal. Range of resection of the vertebral column at the apex of the deformity included apical vertebra and both cephalic and/or caudal adjacent wedged vertebrae. Totally, 32 vertebrae had been removed in 13 patients, with 2.42 vertebrae being removed on average in each case. The average fusion extent was 7.69 vertebrae. Mean operation time was 266 min with average blood loss of 2,411.54 ml during operation. Patients were followed up for an average duration of 2.54 years. Deformity correction was 59% in the coronal plane (from 79.7 degrees to 32.4 degrees ) postoperatively and 33.7 degrees (57% correction) at 2 years follow-up. In the sagittal plane, correction was from preoperative 85.9 degrees to 27.5 degrees immediately after operation, and 32.0 degrees at 2 years follow-up. Postoperative pain was reduced from preoperative 1.77 to 0.54 at 2 years follow-up in visual analog scale. SRS-24 scale was from 38.2 preoperatively to 76.9 at 2 years follow

  5. Influence of Corticospinal Tracts from Higher Order Motor Cortices on Recruitment Curve Properties in Stroke

    Science.gov (United States)

    Potter-Baker, Kelsey A.; Varnerin, Nicole M.; Cunningham, David A.; Roelle, Sarah M.; Sankarasubramanian, Vishwanath; Bonnett, Corin E.; Machado, Andre G.; Conforto, Adriana B.; Sakaie, Ken; Plow, Ela B.

    2016-01-01

    Background: Recruitment curves (RCs) acquired using transcranial magnetic stimulation are commonly used in stroke to study physiologic functioning of corticospinal tracts (CST) from M1. However, it is unclear whether CSTs from higher motor cortices contribute as well. Objective: To explore whether integrity of CST from higher motor areas, besides M1, relates to CST functioning captured using RCs. Methods: RCs were acquired for a paretic hand muscle in patients with chronic stroke. Metrics describing gain and overall output of CST were collected. CST integrity was defined by diffusion tensor imaging. For CST emerging from M1 and higher motor areas, integrity (fractional anisotropy) was evaluated in the region of the posterior limb of the internal capsule, the length of CST and in the region of the stroke lesion. Results: We found that output and gain of RC was related to integrity along the length of CST emerging from higher motor cortices but not the M1. Conclusions: Our results suggest that RC parameters in chronic stroke infer function primarily of CST descending from the higher motor areas but not M1. RCs may thus serve as a simple, in-expensive means to assess re-mapping of alternate areas that is generally studied with resource-intensive neuroimaging in stroke. PMID:27013942

  6. Self-related processing and deactivation of cortical midline regions in disorders of consciousness

    Directory of Open Access Journals (Sweden)

    Julia Sophia eCrone

    2013-08-01

    Full Text Available Self-related stimuli activate anterior parts of cortical midline regions, which normally show task-induced deactivation. Deactivation in medial posterior and frontal regions is associated with the ability to focus attention on the demands of the task, and therefore, with consciousness. Studies investigating patients with impaired consciousness, that is, patients in minimally conscious state and patients with unresponsive wakefulness syndrome (formerly vegetative state, demonstrate that these patients show responses to self-related content in the anterior cingulate cortex. However, it remains unclear if these responses are an indication for conscious processing of stimuli or are due to automatic processing. To shed further light on this issue, we investigated responses of cortical midline regions to the own and another name in 27 patients with a disorder of consciousness and compared them to task-induced deactivation. While almost all of the control subjects responding to the own name demonstrated higher activation due to the self-related content in anterior midline regions and additional deactivation, none of the responding patients did so. Differences between groups showed a similar pattern of findings. Despite the relation between behavioral responsiveness in patients and activation in response to the own name, the findings of this study do not provide evidence for a direct association of activation in anterior midline regions and conscious processing. The deficits in processing of self-referential content in anterior midline regions may rather be due to general impairments in cognitive processing and not particularly linked to impaired consciousness.

  7. Borders and comparative cytoarchitecture of the perirhinal and postrhinal cortices in an F1 hybrid mouse.

    Science.gov (United States)

    Beaudin, Stephane A; Singh, Teghpal; Agster, Kara L; Burwell, Rebecca D

    2013-02-01

    We examined the cytoarchitectonic and chemoarchitectonic organization of the cortical regions associated with the posterior rhinal fissure in the mouse brain, within the framework of what is known about these regions in the rat. Primary observations were in a first-generation hybrid mouse line, B6129PF/J1. The F1 hybrid was chosen because of the many advantages afforded in the study of the molecular and cellular bases of learning and memory. Comparisons with the parent strains, the C57BL6/J and 129P3/J are also reported. Mouse brain tissue was processed for visualization of Nissl material, myelin, acetyl cholinesterase, parvalbumin, and heavy metals. Tissue stained for heavy metals by the Timm's method was particularly useful in the assignment of borders and in the comparative analyses because the patterns of staining were similar across species and strains. As in the rat, the areas examined were parcellated into 2 regions, the perirhinal and the postrhinal cortices. The perirhinal cortex was divided into areas 35 and 36, and the postrhinal cortex was divided into dorsal (PORd) and ventral (PORv) subregions. In addition to identifying the borders of the perirhinal cortex, we were able to identify a region in the mouse brain that shares signature features with the rat postrhinal cortex.

  8. Nonfluent/Agrammatic PPA with In-Vivo Cortical Amyloidosis and Pick’s Disease Pathology

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    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.

  9. Cortical areas related to performance of WAIS Digit Symbol Test: a functional imaging study.

    Science.gov (United States)

    Usui, Nobuo; Haji, Tomoki; Maruyama, Masakazu; Katsuyama, Narumi; Uchida, Shinya; Hozawa, Atsushi; Omori, Kahoru; Tsuji, Ichiro; Kawashima, Ryuta; Taira, Masato

    2009-09-29

    Many neuropsychological studies have shown that the Digit Symbol Test (DST) of the Wechsler Adult Intelligence Scale (WAIS) is useful for screening for dysfunctions of the brain. However, it remains unclear which brain areas are actually involved in the performance of DST and what brain functions are used for executing this test. In this study, we examined the cortical areas related to cognitive aspects of DST using functional magnetic resonance imaging (fMRI) and determined executive brain functions involved in this test on the basis of fMRI results. Eleven healthy young adults (mean=21.6 years) performed a modified DST (mDST) task and its control task, which required a simple graphomotor response during fMRI data acquisition. The direct comparison of brain activations between the mDST task and the control task revealed greater activations in a fronto-parietal cortical network, including the bilateral inferior frontal sulci, left middle frontal gyrus (close to the frontal eye field) and left posterior parietal cortex. These activations are interpreted as reflecting the visual search process and/or the updating process of working memory during the mDST task execution. Furthermore, we found a positive correlation between the number of correct responses and activations in the bilateral inferior frontal regions, suggesting that these prefrontal areas have a crucial role in the performance of DST in a healthy young adult population.

  10. Complexity of motor sequences and cortical reorganization in Parkinson's disease: a functional MRI study.

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    Stefano Caproni

    Full Text Available Motor impairment is the most relevant clinical feature in Parkinson's disease (PD. Functional imaging studies on motor impairment in PD have revealed changes in the cortical motor circuits, with particular involvement of the fronto-striatal network. The aim of this study was to assess brain activations during the performance of three different motor exercises, characterized by progressive complexity, using a functional fMRI multiple block paradigm, in PD patients and matched control subjects. Unlike from single-task comparisons, multi-task comparisons between similar exercises allowed to analyse brain areas involved in motor complexity planning and execution. Our results showed that in the single-task comparisons the involvement of primary and secondary motor areas was observed, consistent with previous findings based on similar paradigms. Most notably, in the multi-task comparisons a greater activation of supplementary motor area and posterior parietal cortex in PD patients, compared with controls, was observed. Furthermore, PD patients, compared with controls, had a lower activation of the basal ganglia and limbic structures, presumably leading to the impairment in the higher levels of motor control, including complexity planning and execution. The findings suggest that in PD patients occur both compensatory mechanisms and loss of efficiency and provide further insight into the pathophysiological role of distinct cortical and subcortical areas in motor dysfunction.

  11. Complexity of motor sequences and cortical reorganization in Parkinson's disease: a functional MRI study.

    Science.gov (United States)

    Caproni, Stefano; Muti, Marco; Principi, Massimo; Ottaviano, Pierfausto; Frondizi, Domenico; Capocchi, Giuseppe; Floridi, Piero; Rossi, Aroldo; Calabresi, Paolo; Tambasco, Nicola

    2013-01-01

    Motor impairment is the most relevant clinical feature in Parkinson's disease (PD). Functional imaging studies on motor impairment in PD have revealed changes in the cortical motor circuits, with particular involvement of the fronto-striatal network. The aim of this study was to assess brain activations during the performance of three different motor exercises, characterized by progressive complexity, using a functional fMRI multiple block paradigm, in PD patients and matched control subjects. Unlike from single-task comparisons, multi-task comparisons between similar exercises allowed to analyse brain areas involved in motor complexity planning and execution. Our results showed that in the single-task comparisons the involvement of primary and secondary motor areas was observed, consistent with previous findings based on similar paradigms. Most notably, in the multi-task comparisons a greater activation of supplementary motor area and posterior parietal cortex in PD patients, compared with controls, was observed. Furthermore, PD patients, compared with controls, had a lower activation of the basal ganglia and limbic structures, presumably leading to the impairment in the higher levels of motor control, including complexity planning and execution. The findings suggest that in PD patients occur both compensatory mechanisms and loss of efficiency and provide further insight into the pathophysiological role of distinct cortical and subcortical areas in motor dysfunction.

  12. Auditory cortical delta-entrainment interacts with oscillatory power in multiple fronto-parietal networks.

    Science.gov (United States)

    Keitel, Anne; Ince, Robin A A; Gross, Joachim; Kayser, Christoph

    2017-02-15

    The timing of slow auditory cortical activity aligns to the rhythmic fluctuations in speech. This entrainment is considered to be a marker of the prosodic and syllabic encoding of speech, and has been shown to correlate with intelligibility. Yet, whether and how auditory cortical entrainment is influenced by the activity in other speech-relevant areas remains unknown. Using source-localized MEG data, we quantified the dependency of auditory entrainment on the state of oscillatory activity in fronto-parietal regions. We found that delta band entrainment interacted with the oscillatory activity in three distinct networks. First, entrainment in the left anterior superior temporal gyrus (STG) was modulated by beta power in orbitofrontal areas, possibly reflecting predictive top-down modulations of auditory encoding. Second, entrainment in the left Heschl's Gyrus and anterior STG was dependent on alpha power in central areas, in line with the importance of motor structures for phonological analysis. And third, entrainment in the right posterior STG modulated theta power in parietal areas, consistent with the engagement of semantic memory. These results illustrate the topographical network interactions of auditory delta entrainment and reveal distinct cross-frequency mechanisms by which entrainment can interact with different cognitive processes underlying speech perception.

  13. Volume reductions in frontopolar and left perisylvian cortices in methamphetamine induced psychosis.

    Science.gov (United States)

    Aoki, Yuta; Orikabe, Lina; Takayanagi, Yoichiro; Yahata, Noriaki; Mozue, Yuriko; Sudo, Yasuhiko; Ishii, Tatsuji; Itokawa, Masanari; Suzuki, Michio; Kurachi, Masayoshi; Okazaki, Yuji; Kasai, Kiyoto; Yamasue, Hidenori

    2013-07-01

    Consumption of methamphetamine disturbs dopaminergic transmission and sometimes provokes schizophrenia-like-psychosis, named methamphetamine-associated psychosis (MAP). While previous studies have repeatedly reported regional volume reductions in the frontal and temporal areas as neuroanatomical substrates for psychotic symptoms, no study has examined whether such neuroanatomical substrates exist or not in patients with MAP. Magnetic resonance images obtained from twenty patients with MAP and 20 demographically-matched healthy controls (HC) were processed for voxel-based morphometry (VBM) using Diffeomorphic Anatomical Registration using Exponentiated Lie Algebra. An analysis of covariance model was adopted to identify volume differences between subjects with MAP and HC, treating intracranial volume as a confounding covariate. The VBM analyses showed significant gray matter volume reductions in the left perisylvian structures, such as the posterior inferior frontal gyrus and the anterior superior temporal gyrus, and the frontopolar cortices, including its dorsomedial, ventromedial, dorsolateral, and ventrolateral portions, and white matter volume reduction in the orbitofrontal area in the patients with MAP compared with the HC subjects. The smaller regional gray matter volume in the medial portion of the frontopolar cortex was significantly correlated with the severe positive symptoms in the individuals with MAP. The volume reductions in the left perisylvian structure suggest that patients with MAP have a similar pathophysiology to schizophrenia, whereas those in the frontopolar cortices and orbitofrontal area suggest an association with antisocial traits or vulnerability to substance dependence.

  14. Posterior Ischemic Optic Neuropathy Following Percutaneous Nephrolithotomy

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    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. Sequential evolution of cortical activity and effective connectivity of swallowing using fMRI.

    Science.gov (United States)

    Mihai, Paul Glad; Otto, Mareile; Platz, Thomas; Eickhoff, Simon B; Lotze, Martin

    2014-12-01

    Swallowing consists of a hierarchical sequence of primary motor and somatosensory processes. The temporal interplay of different phases is complex and clinical disturbances frequent. Of interest was the temporal interaction of the swallowing network. Time resolution optimized functional magnetic resonance imaging was used to describe the temporal sequence of representation sites of swallowing and their functional connectivity. Sixteen young healthy volunteers were investigated who swallowed 2 ml of water 20 times per run with a repetition time for functional imaging of 514 ms. After applying the general linear model approach to identify activation magnitude in preselected regions of interest repeated measures analysis of variance (rmANOVA) was used to detect relevant effects on lateralization, time, and onset. Furthermore, dynamic causal modeling (DCM) was applied to uncover where the input enters the model and the way in which the cortical regions are connected. The temporal analysis revealed a successive activation starting at the premotor cortex, supplementary motor area (SMA), and bilateral thalamus, followed by the primary sensorimotor cortex, the posterior insula, and cerebellum and culminating with activation in the pons shortly before subsiding. The rmANOVA revealed that activation was lateralized initially to the left hemisphere and gradually moved to the right hemisphere over time. The group random effects DCM analysis resulted in a most likely model that consisted of inputs to SMA and M1S1, bidirectionally connected, and a one-way connection from M1S1 to the posterior insula.

  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.

  3. Functionally aberrant electrophysiological cortical connectivities in first episode medication-naive schizophrenics from three psychiatry centers

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    Dietrich eLehmann‡

    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.

  4. Attention Modulates the Auditory Cortical Processing of Spatial and Category Cues in Naturalistic Auditory Scenes

    Science.gov (United States)

    Renvall, Hanna; Staeren, Noël; Barz, Claudia S.; Ley, Anke; Formisano, Elia

    2016-01-01

    This combined fMRI and MEG study investigated brain activations during listening and attending to natural auditory scenes. We first recorded, using in-ear microphones, vocal non-speech sounds, and environmental sounds that were mixed to construct auditory scenes containing two concurrent sound streams. During the brain measurements, subjects attended to one of the streams while spatial acoustic information of the scene was either preserved (stereophonic sounds) or removed (monophonic sounds). Compared to monophonic sounds, stereophonic sounds evoked larger blood-oxygenation-level-dependent (BOLD) fMRI responses in the bilateral posterior superior temporal areas, independent of which stimulus attribute the subject was attending to. This finding is consistent with the functional role of these regions in the (automatic) processing of auditory spatial cues. Additionally, significant differences in the cortical activation patterns depending on the target of attention were observed. Bilateral planum temporale and inferior frontal gyrus were preferentially activated when attending to stereophonic environmental sounds, whereas when subjects attended to stereophonic voice sounds, the BOLD responses were larger at the bilateral middle superior temporal gyrus and sulcus, previously reported to show voice sensitivity. In contrast, the time-resolved MEG responses were stronger for mono- than stereophonic sounds in the bilateral auditory cortices at ~360 ms after the stimulus onset when attending to the voice excerpts within the combined sounds. The observed effects suggest that during the segregation of auditory objects from the auditory background, spatial sound cues together with other relevant temporal and spectral cues are processed in an attention-dependent manner at the cortical locations generally involved in sound recognition. More synchronous neuronal activation during monophonic than stereophonic sound processing, as well as (local) neuronal inhibitory mechanisms in

  5. Neuronal dysfunction and disconnection of cortical hubs in non-demented subjects with elevated amyloid burden

    Science.gov (United States)

    Drzezga, Alexander; Van Dijk, Koene R. A.; Sreenivasan, Aishwarya; Talukdar, Tanveer; Sullivan, Caroline; Schultz, Aaron P.; Sepulcre, Jorge; Putcha, Deepti; Greve, Doug; Johnson, Keith A.; Sperling, Reisa A.

    2011-01-01

    Disruption of functional connectivity between brain regions may represent an early functional consequence of β-amyloid pathology prior to clinical Alzheimer's disease. We aimed to investigate if non-demented older individuals with increased amyloid burden demonstrate disruptions of functional whole-brain connectivity in cortical hubs (brain regions typically highly connected to multiple other brain areas) and if these disruptions are associated with neuronal dysfunction as measured with fluorodeoxyglucose-positron emission tomography. In healthy subjects without cognitive symptoms and patients with mild cognitive impairment, we used positron emission tomography to assess amyloid burden and cerebral glucose metabolism, structural magnetic resonance imaging to quantify atrophy and novel resting state functional magnetic resonance imaging processing methods to calculate whole-brain connectivity. Significant disruptions of whole-brain connectivity were found in amyloid-positive patients with mild cognitive impairment in typical cortical hubs (posterior cingulate cortex/precuneus), strongly overlapping with regional hypometabolism. Subtle connectivity disruptions and hypometabolism were already present in amyloid-positive asymptomatic subjects. Voxel-based morphometry measures indicate that these findings were not solely a consequence of regional atrophy. Whole-brain connectivity values and metabolism showed a positive correlation with each other and a negative correlation with amyloid burden. These results indicate that disruption of functional connectivity and hypometabolism may represent early functional consequences of emerging molecular Alzheimer's disease pathology, evolving prior to clinical onset of dementia. The spatial overlap between hypometabolism and disruption of connectivity in cortical hubs points to a particular susceptibility of these regions to early Alzheimer's-type neurodegeneration and may reflect a link between synaptic dysfunction and functional

  6. Flexor Digitorum Accessorius Longus: Importance of Posterior Ankle Endoscopy

    Science.gov (United States)

    Batista, Jorge Pablo; del Vecchio, Jorge Javier; Golanó, Pau; Vega, Jordi

    2015-01-01

    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. PMID:26060592

  7. 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.

  8. 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.

  9. Predisposing factors in posterior circulation infarcts: a vascular morphological assessment

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    Coban, Goekcen; Cifci, Egemen; Yildirim, Erkan; Agildere, Ahmet Muhtesem [Baskent University Faculty of Medicine, Department of Radiology, Konya (Turkey)

    2015-05-01

    The aim of the study is to assess the effect of shape, diameter, elongation and deviation criteria of basilar artery (BA), convergence angle and diameter variations of vertebral arteries, and concurrent chronic diseases on posterior circulation infarcts. Between January 2010 and May 2013, 186 patients who underwent brain and diffusion magnetic resonance imaging (MRI) with suspected cerebrovascular accident and were diagnosed with posterior circulation infarct and 120 infarct negative control subjects were included in this case-control retrospective study. Vertebral artery (VA) and BA diameter, right (R) and left (L) VA angles at the level of bifurcation, and BA elongation-deviation, and shape of BA were assessed in a total of 306 subjects. Ischemic lesions in the posterior circulation were classified according to their anatomical location and vascular perfusion areas. No significant difference was noted between the control and patient groups with respect to BA diameter (p = 0.676). The most effective risk factors for posterior circulation infarcts were as follows: BA elongation of 2 or 3, BA transverse location of 2 or 3, increase in left VA angle, and history of hypertension, hypercholesterolemia, and diabetes mellitus. Our results suggest that prominent elongation and deviation, C and J shape of BA, and increased L VA angle may be the predictors of at-risk patients in posterior circulation infarcts. Reporting marked morphological BA and VA variations detected at routine brain MRI will aid in selection of patients. Timely detection and treatment of at-risk patients may be life-saving. (orig.)

  10. Biochemical and Clinical Assessments of Segmental Maxillary Posterior Tooth Intrusion

    Science.gov (United States)

    Tasanapanont, Jintana; Wattanachai, Tanapan; Apisariyakul, Janya; Pothacharoen, Peraphan; Kongtawelert, Prachya; Midtbø, Marit

    2017-01-01

    Objective. To compare chondroitin sulphate (CS) levels around maxillary second premolars, first molars, and second molars between the unloaded and the loaded periods and to measure the rates of intrusion of maxillary posterior teeth during segmental posterior tooth intrusion. Materials and Methods. In this prospective clinical study, 105 teeth (from 15 patients exhibiting anterior open bite and requiring maxillary posterior tooth intrusion) were studied. Competitive ELISA was used to detect CS levels. Dental casts (during the unloaded and loaded periods) were scanned, and posterior tooth intrusion distances were measured. Results. During the unloaded period, the median CS levels around maxillary second premolars, first molars, second molars (experimental teeth), and mandibular first molars (negative control) were 0.006, 0.055, 0.056, and 0.012 and during the loaded period were 2.592, 5.738, 4.727, and 0.163 ng/μg of total protein, respectively. The median CS levels around experimental teeth were significantly elevated during the loaded period. The mean rates of maxillary second premolar and first and second molar intrusion were 0.72, 0.58, and 0.40 mm/12 weeks, respectively. Conclusions. Biochemical and clinical assessments suggested that the segmental posterior tooth intrusion treatment modality with 50 g of vertical force per side was sufficient. Trial Registration. The study is registered as TCTR20170206006. PMID:28321256

  11. Features extraction in anterior and posterior cruciate ligaments analysis.

    Science.gov (United States)

    Zarychta, P

    2015-12-01

    The main aim of this research is finding the feature vectors of the anterior and posterior cruciate ligaments (ACL and PCL). These feature vectors have to clearly define the ligaments structure and make it easier to diagnose them. Extraction of feature vectors is obtained by analysis of both anterior and posterior cruciate ligaments. This procedure is performed after the extraction process of both ligaments. In the first stage in order to reduce the area of analysis a region of interest including cruciate ligaments (CL) is outlined in order to reduce the area of analysis. In this case, the fuzzy C-means algorithm with median modification helping to reduce blurred edges has been implemented. After finding the region of interest (ROI), the fuzzy connectedness procedure is performed. This procedure permits to extract the anterior and posterior cruciate ligament structures. In the last stage, on the basis of the extracted anterior and posterior cruciate ligament structures, 3-dimensional models of the anterior and posterior cruciate ligament are built and the feature vectors created. This methodology has been implemented in MATLAB and tested on clinical T1-weighted magnetic resonance imaging (MRI) slices of the knee joint. The 3D display is based on the Visualization Toolkit (VTK).

  12. 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

  13. Variation in functional connectivity along anterior-to-posterior intraparietal sulcus, and relationship with age across late childhood and adolescence

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    Sarah A. Vinette

    2015-06-01

    Full Text Available The intraparietal sulcus (IPS, a region in the dorsal attention network (DAN, has been implicated in multi-sensory attention and working memory. Working memory and attention develop across childhood; changes in functional connectivity within the DAN may relate to this maturation. Previous findings regarding fronto-parietal intrinsic functional connectivity age-effects were mixed. Our study aimed to circumvent limitations of previous work using a large cross-sectional sample, 183 typically developing participants 6.5–20 years, from the Autism Brain Imaging Data Exchange, and seed regions along the anterior-to-posterior axis of the IPS. These seeds, IPS0-4, were entered into functional connectivity models. Group-level models investigated differential connectivity along the IPS and relationships with age. Anterior IPS3/4 exhibited greater connectivity with sensorimotor/pre-motor regions. Posterior IPS0/1 demonstrated greater connectivity with dorsal and ventral visual regions. Positive age-effects were found between IPS3-4 and visual regions. Negative age-effects were found between IPS and superior parietal and medial orbitofrontal cortices. Follow-up region of interest analyses were used to estimate age-effects for DAN and anticorrelated default mode network regions. Results suggest age-effects on IPS functional connectivity are relatively modest, and may differ pre- and across-adolescence. Studying typical age-related connectivity variability within this network may help to understand neurodevelopmental disorders marked by impaired attention.

  14. Cortical thickness abnormalities in late adolescence with online gaming addiction.

    Directory of Open Access Journals (Sweden)

    Kai Yuan

    Full Text Available Online gaming addiction, as the most popular subtype of Internet addiction, had gained more and more attention from the whole world. However, the structural differences in cortical thickness of the brain between adolescents with online gaming addiction and healthy controls are not well unknown; neither was its association with the impaired cognitive control ability. High-resolution magnetic resonance imaging scans from late adolescence with online gaming addiction (n = 18 and age-, education- and gender-matched controls (n = 18 were acquired. The cortical thickness measurement method was employed to investigate alterations of cortical thickness in individuals with online gaming addiction. The color-word Stroop task was employed to investigate the functional implications of the cortical thickness abnormalities. Imaging data revealed increased cortical thickness in the left precentral cortex, precuneus, middle frontal cortex, inferior temporal and middle temporal cortices in late adolescence with online gaming addiction; meanwhile, the cortical thicknesses of the left lateral orbitofrontal cortex (OFC, insula, lingual gyrus, the right postcentral gyrus, entorhinal cortex and inferior parietal cortex were decreased. Correlation analysis demonstrated that the cortical thicknesses of the left precentral cortex, precuneus and lingual gyrus correlated with duration of online gaming addiction and the cortical thickness of the OFC correlated with the impaired task performance during the color-word Stroop task in adolescents with online gaming addiction. The findings in the current study suggested that the cortical thickness abnormalities of these regions may be implicated in the underlying pathophysiology of online gaming addiction.

  15. Cortical thickness abnormalities in late adolescence with online gaming addiction.

    Science.gov (United States)

    Yuan, Kai; Cheng, Ping; Dong, Tao; Bi, Yanzhi; Xing, Lihong; Yu, Dahua; Zhao, Limei; Dong, Minghao; von Deneen, Karen M; Liu, Yijun; Qin, Wei; Tian, Jie

    2013-01-01

    Online gaming addiction, as the most popular subtype of Internet addiction, had gained more and more attention from the whole world. However, the structural differences in cortical thickness of the brain between adolescents with online gaming addiction and healthy controls are not well unknown; neither was its association with the impaired cognitive control ability. High-resolution magnetic resonance imaging scans from late adolescence with online gaming addiction (n = 18) and age-, education- and gender-matched controls (n = 18) were acquired. The cortical thickness measurement method was employed to investigate alterations of cortical thickness in individuals with online gaming addiction. The color-word Stroop task was employed to investigate the functional implications of the cortical thickness abnormalities. Imaging data revealed increased cortical thickness in the left precentral cortex, precuneus, middle frontal cortex, inferior temporal and middle temporal cortices in late adolescence with online gaming addiction; meanwhile, the cortical thicknesses of the left lateral orbitofrontal cortex (OFC), insula, lingual gyrus, the right postcentral gyrus, entorhinal cortex and inferior parietal cortex were decreased. Correlation analysis demonstrated that the cortical thicknesses of the left precentral cortex, precuneus and lingual gyrus correlated with duration of online gaming addiction and the cortical thickness of the OFC correlated with the impaired task performance during the color-word Stroop task in adolescents with online gaming addiction. The findings in the current study suggested that the cortical thickness abnormalities of these regions may be implicated in the underlying pathophysiology of online gaming addiction.

  16. Heterotopic neurogenesis in a rat with cortical heterotopia.

    Science.gov (United States)

    Lee, K S; Collins, J L; Anzivino, M J; Frankel, E A; Schottler, F

    1998-11-15

    Early cellular development was studied in the neocortex of the tish rat. This neurological mutant is seizure-prone and displays cortical heterotopia similar to those observed in certain epileptic patients. The present study demonstrates that a single cortical preplate is formed in a typical superficial position of the developing tish neocortex. In contrast, two cortical plates are formed: one in a normotopic position and a second in a heterotopic position in the intermediate zone. As the normotopic cortical plate is formed, it characteristically separates the subplate cells from the superficial Cajal-Retzius cells. In contrast, the heterotopic cortical plate is not intercalated between the preplate cells because of its deeper position in the developing cortex. Cellular proliferation occurs in two zones of the developing tish cortex. One proliferative zone is located in a typical position in the ventricular/subventricular zone. A second proliferative zone is located in a heterotopic position in the superficial intermediate zone, i.e., between the two cortical plates. This misplaced proliferative zone may contribute cells to both the normotopic and heterotopic cortical plates. Taken together, these findings indicate that misplaced cortical plate cells, but not preplate cells, comprise the heterotopia of the tish cortex. Heterotopic neurogenesis is an early developmental event that is initiated before the migration of most cortical plate cells. It is concluded that misplaced cellular proliferation, in addition to disturbed neuronal migration, can play a key role in the formation of large cortical heterotopia.

  17. Cegueira cortical: relato de dois casos clínicos Cortical blindness: report of two cases

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    Raquel de Lima e Silva

    2001-06-01

    Full Text Available O objetivo deste trabalho é relatar dois casos de cegueira cortical atendidos no serviço de urgência da Clínica de Olhos da Santa Casa de Belo Horizonte. A cegueira cortical é uma condição clínica rara e bilateral, de causa isquêmica, caracterizada por lesão no córtex cerebral. Nos presentes casos, o diagnóstico foi feito pela sintomatologia clínica, pelos achados oftalmológicos e pelas alterações obtidas por imagem. Em ambos houve evolução rápida da doença, com perda visual súbita importante. O acompanhamento oftalmológico não revelou melhora significativa da acuidade visual final. A baixa acuidade visual é um sinal importante em oftalmologia e deve ser avaliada com cautela e atenção, visto que pode ser causada pela cegueira cortical, condição rara, grave e ainda pouco estudada no nosso meio.The aim of this work is to report two cases of cortical blindness, evaluated at an ophthalmologic service (Clínica de Olhos da Santa Casa de Belo Horizonte. Cortical blindness is a rare, usually ischemic, bilateral retrogeniculate lesion. The two diagnoses were based on patient complaints, ophthalmologic data and image signs. Both patients suddenly lost their visual function. None presented a significant improvement in their final vision acuity during the evolution. Subnormal visual acuity is an important ophthalmologic sign that must be seen with concern and attention since it may be caused by cortical blindness, a rare and serious condition not yet well studied in our Country.

  18. Posterior vaginal wall cyst of Mullerian origin: a case report

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    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

  19. Posterior resin-based composite: review of the literature.

    Science.gov (United States)

    Burgess, J O; Walker, Richard; Davidson, J M

    2002-01-01

    The use of direct posterior resin-based composite has increased primarily due to patient esthetic desires and product improvements. Other factors (substantiated or not) contributing to increased use of resin-based composite are environmental and health concerns with dental amalgam. New visible light cured resin-based composite products are introduced yearly, as manufacturers continue to improve this tooth-colored restorative material. This paper will characterize current posterior resin-based composite materials (hybrid, microfill, flowable, and packable), review recent in vitro and clinical research, and recommend indications for these materials. In addition, the literature on compomers will be reviewed and recommendation made for their use. The data indicates that composite resin is a technique sensitive restorative material that can be used in large preparations if proper manipulation and isolation can be maintained. Compomers may also be used as an esthetic posterior restorative if proper isolation is provided.

  20. 'Split posterior tooth': conservative clinical re-attachment.

    Science.gov (United States)

    Abraham, Sathish; Chacko, Lisa Neelathil

    2014-07-30

    Trauma is the prime causative factor for fracture of teeth/dentition. Many procedural management options are followed successfully in relation to the anterior teeth. However, most posterior cases where the tooth is fractured have only limited options to pursue to save the tooth. Fractured teeth, whether they are vital/non-vital, are predominantly managed with surgical options. This paper discusses a conservative approach to reattaching a split posterior tooth. A split tooth situation is mostly an absolute indication for extraction, but the clinician may go in for extensive surgical procedures if he/she wishes to save it. The reattachment of the tooth can be successfully done and it can be put to function. This paper discusses how a split posterior tooth can be treated successfully, although depending on multiple factors. A full crown cemented after successful reattachment and root canal therapy would provide sufficient support in order for the tooth to heal.

  1. Mature Teratoma of the Posterior Mediastinum: A Case Report

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    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.

  2. Factors influencing the treatment of posterior cruciate ligament injury.

    Science.gov (United States)

    Ittivej, Kittimasak; Prompaet, Sureeporn; Rojanasthien, Sattaya

    2005-10-01

    The primary objective was to determine the factors which influence the requirement of surgical treatment of posterior cruciate ligament (PCL) injury. Ninety one PCL injured patients diagnosed in the "Sports Medicine Clinic", Maharaj Nakorn Chiang Mai Hospital from January 1998 to December 2000 were included in the present study. There were 63 males and 28 females with an average age of 29 years. All of the PCL-insufficient knees were initially treated by non-operative method including 3 phases of rehabilitation. They were followed through to the end of December 2003. Analysis showed that the degree of posterior laxity was the only factor that had a statistical significant correlation to failure of conservative treatment. In addition, the need for surgical treatment was not associated with gender age, cause of injury, and concomitant of injury. The authors concluded that PCL injured patients with posterior laxity greater than 10 millimeters should be treated by PCL reconstruction.

  3. 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.

  4. Differential Modification of Cortical and Thalamic Projections to Cat Primary Auditory Cortex Following Early- and Late-Onset Deafness.

    Science.gov (United States)

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

    2015-10-15

    Following sensory deprivation, primary somatosensory and visual cortices undergo crossmodal plasticity, which subserves the remaining modalities. However, controversy remains regarding the neuroplastic potential of primary auditory cortex (A1). To examine this, we identified cortical and thalamic projections to A1 in hearing cats and those with early- and late-onset deafness. Following early deafness, inputs from second auditory cortex (A2) are amplified, whereas the number originating in the dorsal zone (DZ) decreases. In addition, inputs from the dorsal medial geniculate nucleus (dMGN) increase, whereas those from the ventral division (vMGN) are reduced. In late-deaf cats, projections from the anterior auditory field (AAF) are amplified, whereas those from the DZ decrease. Additionally, in a subset of early- and late-deaf cats, area 17 and the lateral posterior nucleus (LP) of the visual thalamus project concurrently to A1. These results demonstrate that patterns of projections to A1 are modified following deafness, with statistically significant changes occurring within the auditory thalamus and some cortical areas. Moreover, we provide anatomical evidence for small-scale crossmodal changes in projections to A1 that differ between early- and late-onset deaf animals, suggesting that potential crossmodal activation of primary auditory cortex differs depending on the age of deafness onset.

  5. Pre-cue fronto-occipital alpha phase and distributed cortical oscillations predict failures of cognitive control.

    Science.gov (United States)

    Hamm, Jordan P; Dyckman, Kara A; McDowell, Jennifer E; Clementz, Brett A

    2012-05-16

    Cognitive control is required for correct performance on antisaccade tasks, including the ability to inhibit an externally driven ocular motor response (a saccade to a peripheral stimulus) in favor of an internally driven ocular motor goal (a saccade directed away from a peripheral stimulus). Healthy humans occasionally produce errors during antisaccade tasks, but the mechanisms associated with such failures of cognitive control are uncertain. Most research on cognitive control failures focuses on poststimulus processing, although a growing body of literature highlights a role of intrinsic brain activity in perceptual and cognitive performance. The current investigation used dense array electroencephalography and distributed source analyses to examine brain oscillations across a wide frequency bandwidth in the period before antisaccade cue onset. Results highlight four important aspects of ongoing and preparatory brain activations that differentiate error from correct antisaccade trials: (1) ongoing oscillatory beta (20-30 Hz) power in anterior cingulate before trial initiation (lower for error trials); (2) instantaneous phase of ongoing alpha/theta (7 Hz) in frontal and occipital cortices immediately before trial initiation (opposite between trial types); (3) gamma power (35-60 Hz) in posterior parietal cortex 100 ms before cue onset (greater for error trials); and (4) phase locking of alpha (5-12 Hz) in parietal and occipital cortices immediately before cue onset (lower for error trials). These findings extend recently reported effects of pre-trial alpha phase on perception to cognitive control processes and help identify the cortical generators of such phase effects.

  6. Total knee reconstruction without posterior stabilization in rheumatoid arthritis patients

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    Radu Prejbeanu

    2010-12-01

    Full Text Available Objectives: to present the results with posterior cruciate ligament-retaining total knee arthroplasty in rheumatoid arthritis (RA patients. Background: Total knee replacement in RA patients has many particularities. One of them is the difficulty of obtaining a proper ligamentous balance.Methods: 24 RA patients were followed for a 5-year period after posterior cruciate ligament-retaining total knee arthroplasty. Clinical assessments analyzed general health status by using Hospital for Special Surgery Knee Evaluation Form (HSSKEF and mediolateral and anteroposterior ligament stability by using varus-valgus and posterior drawer tests. Radiological assessments evaluated axial alignment, size and position of components, radiolucent lines in anteroposterior and lateral standard views, integrity of the posterior cruciate ligament on lateral view X-ray at 45 degrees of flexion.Results: the mean HSSKEF score increased from 32 to 84 points at the end of follow-up. Preoperative mean range of motion was 60 degrees; postoperative mean range of motion was of 105 degrees, with significant statistical difference (p<0.05. The mean femoral component axial deviation was 6 degrees. The tibial component had a mean axial deviation of 1 degree of varus. There were no radioluscency lines of more than 1mm. 21 patients had excellent results. None of the knees was unstable. Conclusion: posterior cruciate ligament-retaining total knee arthroplasty can be used in RA patients without excessive valgus deformity (over 15 degrees, providing thus sufficient stabilization. The outcomes re similar to those patients who followed a posterior stabilized endoprosthesis.

  7. STUDY OF POSTERIOR DIVISION OF INTERNAL ILIAC ARTERY

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    Pavan P Havaldar

    2014-06-01

    Full Text Available Background: The internal iliac artery originates from the common iliac artery at the level of sacroiliac joint. The internal iliac artery descends posterior to the greater sciatic foramen thereby dividing into anterior and posterior divisions. The posterior division of the internal iliac artery is known to give rise to three main branches i.e. iliolumbar artery, lateral sacral artery. Accidental haemorrhage is common during erroneous interpretation of anomalous blood vessels. The knowledge of the normal and the abnormal anatomy of the branches of the internal iliac artery is essential for obstetric surgeons. Methods: 50 adult human pelvic halves were procured from embalmed cadavers of J.J.M. Medical College and S.S.I.M.S & R.C, Davangere, Karnataka, India for the study. Results: Out of 50 specimens, ilio-lumbar artery took origin from posterior division, directly in 22 specimens (44%, with obturator artery in 5 specimens (10% and with superior gluteal artery in 2 specimens (4%. From anterior division, with obturator artery in 6 specimens (12% and with inferior gluteal artery in 1 specimen (2%. From common trunk, as direct branch in 10 specimens (20%, with lateral sacral artery in 1 specimen (2%, with vertebral branch in 1 specimen (2%, with superior gluteal artery in 1 specimen (2% and was found to be absent in 1 specimen (2%. Posterior division of internal iliac artery given origin directly to superior gluteal artery in 44 specimens (88%, with ilio-lumbar artery in 1 specimen (2%, with obturator artery in 2 specimens (4%. Lateral sacral artery from posterior division was observed in 38 specimens (76% and unpaired origin was observed in 7 specimens (14%. Conclusion: Internal iliac artery supplies the pelvic viscera and musculature the knowledge of its branches helpful in pelvis surgeries.

  8. 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.

  9. Pedicle Screw-Based Posterior Dynamic Stabilization: Literature Review

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    Dilip K. Sengupta

    2012-01-01

    Full Text Available Posterior dynamic stabilization (PDS indicates motion preservation devices that are aimed for surgical treatment of activity related mechanical low back pain. A large number of such devices have been introduced during the last 2 decades, without biomechanical design rationale, or clinical evidence of efficacy to address back pain. Implant failure is the commonest complication, which has resulted in withdrawal of some of the PDS devices from the market. In this paper the authors presented the current understanding of clinical instability of lumbar motions segment, proposed a classification, and described the clinical experience of the pedicle screw-based posterior dynamic stabilization devices.

  10. 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.

  11. Management of Posterior Reversible Syndrome in Preeclamptic Women

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    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.

  12. Ossificação do ligamento longitudional posterior: relato de caso Posterior longitudinal ligament ossification: case report

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    Oswaldo Inácio de Tella Jr

    2006-03-01

    Full Text Available 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 longitudinal ligament ossification of cervical spine is a rare condition among caucasians. A 42 years old japanese patient with progressive walking difficulty was diagnosed with this pathology by CT scan and MRI and treated surgically by an anterior approach with arthrodesis. Pathophisiology, racial prevelence, clinical picture, radiological caractheristics and surgical approaches options are revised.

  13. Consistent Reconstruction of Cortical Surfaces from Longitudinal Brain MR Images

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    Li, Gang; Nie, Jingxin; Shen, Dinggang

    2011-01-01

    Accurate and consistent reconstruction of cortical surfaces from longitudinal human brain MR images is of great importance in studying subtle morphological changes of the cerebral cortex. This paper presents a new deformable surface method for consistent and accurate reconstruction of inner, central and outer cortical surfaces from lon