956 resultados para Anterior medial frontal


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Background: Previous magnetic resonance imaging (MRI) studies in young patients with bipolar disorder indicated the presence of grey matter concentration changes as well as microstructural alterations in white matter in various neocortical areas and the corpus callosum. Whether these structural changes are also present in elderly patients with bipolar disorder with long-lasting clinical evolution remains unclear. Methods: We performed a prospective MRI study of consecutive elderly, euthymic patients with bipolar disorder and healthy, elderly controls. We conducted a voxel-based morphometry (VBM) analysis and a tract-based spatial statistics (TBSS) analysis to assess fractional anisotropy and longitudinal, radial and mean diffusivity derived by diffusion tensor imaging (DTI). Results: We included 19 patients with bipolar disorder and 47 controls in our study. Fractional anisotropy was the most sensitive DTI marker and decreased significantly in the ventral part of the corpus callosum in patients with bipolar disorder. Longitudinal, radial and mean diffusivity showed no significant between-group differences. Grey matter concentration was reduced in patients with bipolar disorder in the right anterior insula, head of the caudate nucleus, nucleus accumbens, ventral putamen and frontal orbital cortex. Conversely, there was no grey matter concentration or fractional anisotropy increase in any brain region in patients with bipolar disorder compared with controls. Limitations: The major limitation of our study is the small number of patients with bipolar disorder. Conclusion: Our data document the concomitant presence of grey matter concentration decreases in the anterior limbic areas and the reduced fibre tract coherence in the corpus callosum of elderly patients with long-lasting bipolar disorder.

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Multisensory experiences enhance perceptions and facilitate memory retrieval processes, even when only unisensory information is available for accessing such memories. Using fMRI, we identified human brain regions involved in discriminating visual stimuli according to past multisensory vs. unisensory experiences. Subjects performed a completely orthogonal task, discriminating repeated from initial image presentations intermixed within a continuous recognition task. Half of initial presentations were multisensory, and all repetitions were exclusively visual. Despite only single-trial exposures to initial image presentations, accuracy in indicating image repetitions was significantly improved by past auditory-visual multisensory experiences over images only encountered visually. Similarly, regions within the lateral-occipital complex-areas typically associated with visual object recognition processes-were more active to visual stimuli with multisensory than unisensory pasts. Additional differential responses were observed in the anterior cingulate and frontal cortices. Multisensory experiences are registered by the brain even when of no immediate behavioral relevance and can be used to categorize memories. These data reveal the functional efficacy of multisensory processing.

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BACKGROUND: When and how to operate an early-onset esotropia (onset before 6 months of age) is still controversial. We conducted a retrospective study of such patients operated before the age of 24 months. PATIENTS AND METHODS: 82 patients were operated by one surgeon (GK) and followed by the same team. At 5 years post-operation, evaluation criteria included the residual angle of deviation, visual acuity (Birkhäuser Nr 505, 5 m) and binocularity (Lang stereotest I, Bagolini glasses). RESULTS: At 5 years, the residual angle was excellent (0 degrees to + 5 degrees ) in 67 % good, (>+5 degrees to +10 degrees or 0 to -5 degrees ) in 23 %, and poor (>+10 degrees or <-5 degrees ) in 10 %. During the 5 years of follow-up the rate of reoperation was 9.7 %. Isoacuity was obtained in 62 %, slight amblyopia (2 lines of interocular difference) was present in 32 %, and average amblyopia (> 3 lines of interocular difference) was noted in 6 %. Simultaneous perception was present in 53 %, whereas one eye was suppressed or results were undetermined in 47 %. No patient demonstrated stereoscopy using the Lang's stereotest I. CONCLUSION: The results from our study demonstrate that early surgery of early-onset esotropia has a favourable outcome on both visual acuity and the residual angle of strabismus. Simultaneous perception was achieved in 53 %. These figures are comparable to the results of the ELISSS multicentric study.

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PURPOSE: To report the clinical and genetic study of two families of Egyptian origin with clinical anophthalmia. To further determine the role of the retina and anterior neural fold homeobox gene (RAX) in anophthalmia and associated cerebral malformations. METHODS: Three patients with clinical anophthalmia and first-degree relatives from two consanguineous families of Egyptian origin underwent full ophthalmologic, general and neurologic examination, and blood tests. Cerebral magnetic resonance imaging (MRI) was performed in the index cases of both families. Genomic DNA was prepared from venous leukocytes, and direct sequencing of all the exons and intron-exon junctions of RAX was performed after PCR amplification. RESULTS: Clinical bilateral anophthalmia was observed in all three patients. General and neurologic examinations were normal; obesity and delay in psychomotor development were observed in the isolated case. Orbital MRI showed a hypoplastic orbit with present but rudimentary extraocular muscles and normal lacrimal glands. Cerebral MRI showed agenesis of the optic nerves, optic tracts, and optic chiasma. In the index case of family A, the absence of the frontal and sphenoidal sinuses was also noted. In the index case of family B, only the sphenoidal sinus was absent, and there was significant cortical atrophy. The three patients carried a novel homozygous c.543+3A>G mutation (IVS2+3A>G) in RAX. Parents were healthy heterozygous carriers. No mutations were detected in orthodenticle homeobox 2 (OTX2), ventral anterior homeobox 1 (VAX1), or sex determining region Y-box 2 (SOX2). CONCLUSIONS: This is the first report of a homozygous splicing RAX mutation associated with autosomal recessive bilateral anophthalmia. To our knowledge, only two isolated cases of anophthalmia, three null and one missense case affecting nuclear localization or the DNA-binding homeodomain, have been found to be caused by compound heterozygote RAX mutations. A novel missense RAX mutation was identified in three patients with bilateral anophthalmia and a distinct systemic and neurologic phenotype. The mutation potentially affects splicing of the last exon and is thought to result in a protein that has an aberrant homeodomain and no paired-tail domain. Functional consequences of this change still need to be characterized.

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Se estima que en España la incidencia de la lesión del ligamento cruzado anterior (L.C.A) es de 4 casos por cada 10.000 habitantes/año. Su reconstrucción quirúrgica incluye habitualmente la utilización de autoinjertos (con tejido tendinoso propio del paciente). Los dos más frecuentes son de tendón rotuliano y de tendones isquiotibiales.La lesión del L.C.A y su intervención quirúrgica hace tributario al trabajador de una incapacidad temporal (IT). No existe consenso en cuanto a la elección entre los dos injertos en la cirugía de L.C.A ni se conoce su impacto en la duración de la IT.El objetivo principal de este trabajo es describir la duración de la incapacidad temporal en función de la técnica quirúrgica de autoinjertos utilizada en la reconstrucción del ligamento cruzado anterior.Se trata de cohorte retrospectiva de 151 trabajadores que han sido tributarios de una IT por plastia de ligamento cruzado anterior de la rodilla, utilizando autoinjertos. El ámbito de estudio es una mutua de accidentes de trabajo y enfermedades profesionales de la Seguridad Social (Mutual Midat Cyclops - MC MUTUAL). Los trabajadores han sido intervenidos quirúrgicamente en la Clínica MC-Copérnico de Barcelona, por una de las técnicas (T. rotuliano o T. Isquiotibiales).Para la técnica del Tendón Rotuliano se obtuvo una muestra de 68 trabajadores intervenidos quirúrgicamente, con una DM de 121 días, y para la técnica de los Tendones Isquiotibiales se recogió una muestra de 83 intervenciones quirúrgicas, con una DM de 113. La DM total fue de 117 días de IT.El análisis de los datos no arrojó diferencias estadísticamente significativas en el tiempo de retorno al trabajo entre los trabajadores intervenidos por las técnicas quirúrgicas señaladas.

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Objectif Analyser les résultats, les complications et les pièges rencontrés lors de la période d'apprentissage de la technique de la DALK avec réalisation d'une Big Bubble . Matériels et Méthodes : Étude rétrospective de 20 DALKs réalisées entre 2006 et 2007. L'âge moyen était de 45.21 ans (18 à 76). Le groupe comprenait 7 hommes et 13 femmes. Les indications opératoires étaient : kératocône (n=15), leucome herpétique (n=3) et taie cornéenne post-abcès bactérien (n=2). Le suivi comprenait la MAVC pré et post-opératoire, la réfraction post-opératoire, la transparence de la greffe, la qualité de l'interface donneur/receveur, et l'analyse des complications per et post-opératoires. Résultats Parmi les 20 DALKs, 8 cas ont été transformés en kératoplastie perforante à cause d'une perforation per-opératoire de la membrane de Descemet (40 % des cas). Le suivi moyen était de 7.77 mois. Les meilleures acuités visuelles corrigées moyennes pré et post-opératoires étaient de 0.158 (0.02 à 0.4) et 0.4357 (0.25 à 0.6) pour les DALKs et de 0.125 (0.1 à 0.3) et 0.463 (0.02 à 0.8) pour les DALKs transformées en kératoplastie perforante. Les greffes étaient transparentes dans tous les cas. Dans 3 cas, des plis de l'interface ont constitués une gêne de la qualité visuelle (di ou triplopie). Un haze de l'interface a été observé dans 5 cas avec disparition progressive lors du suivi. Discussion La DALK est une technique efficace dans le traitement des atteintes stromales profondes de la cornée, elle permet de préserver l'endothélium du donneur qui est sain dans ce type de pathologie. Conclusion La réalisation de la Big Bubble lors de la dissection de la Descemet et la qualité de l'interface donneur/receveur demeurent les éléments clés d'une telle procédure. Cette technique opératoire est probablement une des techniques les plus difficiles qu'un chirurgien de la cornée ait à maîtriser.

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Background: Language processing abnormalities and inhibition difficulties are hallmark features of schizophrenia. The objective of this study is to asses the blood oxygenation level-dependent (BOLD) response at two different stages of the illness and compare the frontal activity between adolescents and adults with schizophrenia. Methods: 10 adults with schizophrenia (mean age 31,5 years) and 6 psychotic adolescents with schizophrenic symptoms (mean age 16,2 years) underwent functional magnetic resonance imaging while performing two frontal tasks. Regional activation is compared in the bilateral frontal areas during a covert verbal fluency task (letter version) and a Stroop task (inhibition task). Results: Preliminary results show poorer task performance and less frontal cortex activation during both tasks in the adult group of patients with schizophrenia. In the adolescent patients group, fMRI analysis show significant and larger activity in the left frontal operculum (Broca's area) in the verbal fluency task and greater activity in the medium cingulate during the inhibition phase of the Stroop task. Conclusions: These preliminary findings suggest a decrease of frontal activity in the course of the illness. We assume that schizophrenia contributes to frontal brain activity reduction.

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The discovery of an anterior mediastinal mass requires careful management with specific consideration of the pathology. More than 50% of all mediastinal masses seen in adults are in the anterior mediastinum. The most frequent diagnoses are thymoma, lymphoma, teratoma and benign thyroid tumours. 60% of cases are malignant. Often the clinical and radiological findings do not allow a definitive diagnosis and a histological diagnosis is often required to select the optimal treatment modality. The choice of biopsy technique depends on the localization of the lesion, clinical factors, and the availability of special techniques and equipment. Biopsy may be obtained by trans-thoracic puncture under computed tomography or ultrasound guidance, or by a surgical approach (mediastinotomy or thoracoscopy).

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RATIONALE: Dopamine D2 receptors are the main target of antipsychotic drugs. In the brain, D2 receptors coexpress with adenosine A2A and CB1 cannabinoid receptors, leading to functional interactions. OBJECTIVES: The protein and messenger RNA (mRNA) contents of A2A, D2, and CB1 receptors were quantified in postmortem prefrontal cortex of subjects with schizophrenia. MATERIALS AND METHODS: The study was performed in subjects suffering schizophrenia (n=31) who mainly died by suicide, matched with non-schizophrenia suicide victims (n=13) and non-suicide controls (n=33). The density of receptor proteins was evaluated by immunodetection techniques, and their relative mRNA expression was quantified by quantitative real-time polymerase chain reaction. RESULTS: In schizophrenia, the densities of A2A (90+/-6%, n=24) and D2-like receptors (95+/-5%, n=22) did not differ from those in controls (100%). Antipsychotic treatment did not induce changes in the protein expression. In contrast, the immunodensity of CB1 receptors was significantly decreased (71+/-7%, n=11; p<0.05) in antipsychotic-treated subjects with schizophrenia but not in drug-free subjects (104+/-13%, n=11). The relative mRNA amounts encoding for A2A, D2, and CB1 receptors were similar in brains of drug-free, antipsychotic-treated subjects with schizophrenia and controls. CONCLUSIONS: The findings suggest that antipsychotics induce down-regulation of CB1 receptors in brain. Since A2A, D2, and CB1 receptors coexpress on brain GABAergic neurons and reductions in markers of GABA neurotransmission have been identified in schizophrenia, a lower density of CB1 receptor induced by antipsychotics could represent an adaptative mechanism that reduces the endocannabinoid-mediated suppression of GABA release, contributing to the normalization of cognitive functions in the disorder.

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Fractures or the medial wall of the orbit are uncommon and clinical signs are often discreet. This report was focused on isolated fractures of the medial wall of the orbit. Blow-out trauma is usually the cause. In these cases the clinical signs ranged from simple ecchymosis to blindness by haematoma of the orbital cone. Computed tomography is a major tool for diagnosis and making therapeutic indications for these fractures. Treatment depends on the oculomotor involvements as measured by forced duction tests.

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OBJECTIVES: This study was designed to compare the long-term clinical outcome of coronary artery bypass grafting (CABG) with intracoronary stenting of patients with isolated proximal left anterior descending coronary artery. BACKGROUND: Although numerous trials have compared coronary angioplasty with bypass surgery, none assessed the clinical evaluation in the long term. METHODS: We evaluated the 10-year clinical outcome in the SIMA (Stent versus Internal Mammary Artery grafting) trial. Patients were randomly assigned to stent implantation versus CABG. RESULTS: Of 123 randomized patients, 59 underwent CABG and 62 received a stent (2 patients were excluded). Follow-up after 10 years was obtained for 98% of the randomized patients. Twenty-six patients (42%) in the percutaneous coronary intervention group and 10 patients (17%) in the CABG group reached an end point (p < 0.001). This difference was due to a higher need for additional revascularization. The incidences of death and myocardial infarction were identical at 10%. Progression of the disease requiring additional revascularization was rare (5%) and was similar for the 2 groups. Stent thrombosis occurred in 2 patients (3%). Angina functional class showed no significant differences between the 2 groups. CONCLUSIONS: Both stent implantation and CABG are safe and highly effective in relieving symptoms in patients with isolated, proximal left anterior descending coronary artery stenosis. Stenting with bare-metal stents is associated with a higher need for repeat interventions. The long-term prognosis for these patients is excellent with either mode of revascularization.

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Introduction: The primary somatosensory cortex (SI) contains Brodmann areas (BA) 1, 2, 3a, and 3b. Research in non-human primates showed that BAs 3b, 1, and 2 each contain one full representation of the hand with separate representations for each finger. This research also showed that the finger representation in BA3b has larger and clearer finger somatotopy than BA1 and 2. Although several efforts to map finger somatotopy in SI by fMRI have been made at 1.5 and 3T these studies have yielded variable results and were not able to detect single subject finger somatotopy, probably due to the limited spatial extent of the cortical areas representing a digit (close to the resolution in most fMRI experiments), complications due to acquisition of consistent maps for individual subjects (Schweizer et al 2008), or inter-individual variability in sulcal anatomy impeding group studies. Here, we used 7T fMRI to investigate finger somatotopy in SI, some of its functional characteristics, and its reproducibility. Methods: Eight right-handed male subjects were scanned on a 7T scanner (Siemens Medical, Germany) with an 8-channel Tx/Rx rf-coil (Rapid Biomedical, Germany). 1.3x1.3x1.3mm3 resolution fMRI data were acquired using a sinusoidal readout EPI sequence (Speck et al, 2008) and FOV=210mm, TE/TR=27ms/2.5s, GRAPPA=2. Each volume contained 28 transverse slices covering SI. A single EPI volume with 64 slices was acquired to aid coregistration. 1x1x1mm3 anatomical data were acquire using the MP2RAGE sequence (Marques et al, 2009; TE/TR/TI1,2/TRmprage=2.63ms/7.2ms/0.9,3.2s/5s). Subjects were positioned supine in the scanner with their right arm comfortably against the magnet bore. An experimenter was positioned at the entrance of the bore where he could easily reach and stroke successively the two distal phalanxes of each digit. The order of stroked digit was D1 (thumb)-D3-D5-D2-D4, with 20s ON, 10s OFF alternated. This sequence was repeated four times per run and two functional runs were acquired per subject. Realignment, smoothing (FWHM 2 mm), coregistration of the anatomical to the fMRI data and calculation of t-statistics were done using SPM8. An SI mask was obtained via an F-contrast (p<0.001) over all digits. Within the mask, voxels were labeled with the number of the digit demonstrating the highest t-value for that particular voxel. Results: For all subjects, areas corresponding to the five digits were identified in contralateral SI. BA3b showed the most consistent somatotopic finger representation (see an example in Fig.1). The five digits were localized in a consecutive order in the cortex, with D1 most anterior, inferior and distal and D5, most posterior, superior and medial (mean distance between centres of mass of digit representations ±stderr: 4.2±0.7mm; see Fig. 2). The analysis of average beta values within each finger representation region revealed the specificity of the somatotopic region to the tactile input for each tested finger (except digit 4 and 5). Five of these subjects also presented an orderly and consecutive representation of the five digits in BA1 and 2. Conclusions: Our data reveal that the increased BOLD sensitivity at 7T and the high spatial resolution used in this study allow consistent somatotopic mapping using human touch as a stimulus and that human SI contains at least three separate regions that contain five separate representations of all single contralateral fingers. Moreover, adjacent fingers were represented at adjacent cortical regions across the three SI regions. The spatial organization of SI as reflected in individual subject topography corresponds well with previous electrophysiological data in non-human primates. The small distance between digit representations highlights the need for the high spatial resolution available at 7T.

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Astute control of brain activity states is critical for adaptive behaviours and survival. In mammals and birds, electroencephalographic recordings reveal alternating states of wakefulness, slow wave sleep and paradoxical sleep (or rapid eye movement sleep). This control is profoundly impaired in narcolepsy with cataplexy, a disease resulting from the loss of orexin/hypocretin neurotransmitter signalling in the brain. Narcolepsy with cataplexy is characterized by irresistible bouts of sleep during the day, sleep fragmentation during the night and episodes of cataplexy, a sudden loss of muscle tone while awake and experiencing emotions. The neural mechanisms underlying cataplexy are unknown, but commonly thought to involve those of rapid eye movement-sleep atonia, and cataplexy typically is considered as a rapid eye movement sleep disorder. Here we reassess cataplexy in hypocretin (Hcrt, also known as orexin) gene knockout mice. Using a novel video/electroencephalogram double-blind scoring method, we show that cataplexy is not a state per se, as believed previously, but a dynamic, multi-phased process involving a reproducible progression of states. A knockout-specific state and a stereotypical paroxysmal event were introduced to account for signals and electroencephalogram spectral characteristics not seen in wild-type littermates. Cataplexy almost invariably started with a brief phase of wake-like electroencephalogram, followed by a phase featuring high-amplitude irregular theta oscillations, defining an activity profile distinct from paradoxical sleep, referred to as cataplexy-associated state and in the course of which 1.5-2 s high-amplitude, highly regular, hypersynchronous paroxysmal theta bursts (∼7 Hz) occurred. In contrast to cataplexy onset, exit from cataplexy did not show a predictable sequence of activities. Altogether, these data contradict the hypothesis that cataplexy is a state similar to paradoxical sleep, even if long cataplexies may evolve into paradoxical sleep. Although not exclusive to overt cataplexy, cataplexy-associated state and hypersynchronous paroxysmal theta activities are highly enriched during cataplexy in hypocretin/orexin knockout mice. Their occurrence in an independent narcolepsy mouse model, the orexin/ataxin 3 transgenic mouse, undergoing loss of orexin neurons, was confirmed. Importantly, we document for the first time similar paroxysmal theta hypersynchronies (∼4 Hz) during cataplexy in narcoleptic children. Lastly, we show by deep recordings in mice that the cataplexy-associated state and hypersynchronous paroxysmal theta activities are independent of hippocampal theta and involve the frontal cortex. Cataplexy hypersynchronous paroxysmal theta bursts may represent medial prefrontal activity, associated in humans and rodents with reward-driven motor impulse, planning and conflict monitoring.

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PURPOSE: To investigate whether the prophylactic use of bevacizumab reduces the rate of rubeosis after proton therapy for uveal melanoma and improves the possibility to treat ischemic, reapplicated retina with laser photocoagulation. DESIGN: Comparative retrospective case series. METHODS: Uveal melanoma patients with ischemic retinal detachment and treated with proton therapy were included in this institutional study. Twenty-four eyes received prophylactic intravitreal bevacizumab injections and were compared with a control group of 44 eyes without bevacizumab treatment. Bevacizumab injections were performed at the time of tantalum clip insertion and were repeated every 2 months during 6 months, and every 3 months thereafter. Ultra-widefield angiography allowed determination of the extent of retinal ischemia, which was treated with laser photocoagulation after retinal reapplication. Main outcome measures were the time to rubeosis, the time to retinal reattachment, and the time to laser photocoagulation of ischemic retina. RESULTS: Baseline characteristics were balanced between the groups, except for thicker tumors and larger retinal detachments in the bevacizumab group, potentially to the disadvantage of the study group. Nevertheless, bevacizumab prophylaxis significantly reduced the rate of iris rubeosis from 36% to 4% (log-rank test P = .02) and tended to shorten the time to retinal reapplication until laser photocoagulation of the nonperfusion areas could be performed. CONCLUSIONS: Prophylactic intravitreal bevacizumab in patients treated with proton therapy for uveal melanoma with ischemic retinal detachment prevented anterior segment neovascularization, until laser photocoagulation to the reapplied retina could be performed.