Intraocular Pressure Correlates with Optic Nerve Sheath Diameter in Patients with Normal Tension Glaucoma

PURPOSE: 1. Identify differences in optic nerve sheath diameter (ONSD) as an indirect measure of intracranial pressure (ICP) in glaucoma patients and a healthy population. 2. Identify variables that may correlate with ONSD in primary open-angle glaucoma (POAG) and normal tension glaucoma (NTG) patients. METHODS: Patients with NTG (n = 46) and POAG (n = 61), and healthy controls (n = 42) underwent B-scan ultrasound measurement of ONSD by an observer masked to the patient diagnosis. Intraocular pressure (IOP) was measured in all groups, with additional central corneal thickness (CCT) and visual field defect measurements in glaucomatous patients. Only one eye per patient was selected. Kruskal-Wallis or Mann-Whitney were used to compare the different variables between the diagnostic groups. Spearman correlations were used to explore relationships among these variables. RESULTS: ONSD was not significantly different between healthy, NTG and POAG patients (6.09 ± 0.78, 6.03 ± 0.69, and 5.71 ± 0.83 respectively; p = 0.08). Visual field damage and CCT were not correlated with ONSD in either of the glaucoma groups (POAG, p = 0.31 and 0.44; NTG, p = 0.48 and 0.90 respectively). However, ONSD did correlate with IOP in NTG patients (r = 0.53, p < 0.001), while it did not in POAG patients and healthy controls (p = 0.86, p = 0.46 respectively). Patient's age did not relate to ONSD in any of the groups (p > 0.25 in all groups). CONCLUSIONS: Indirect measurements of ICP by ultrasound assessment of the ONSD may provide further insights into the retrolaminar pressure component in glaucoma. The correlation of ONSD with IOP solely in NTG patients suggests that the translaminar pressure gradient may be of particular importance in this type of glaucoma.

Estudo do comportamento da PIO de 24 horas e frequência de glaucoma em pacientes com síndrome da apnéia obstrutiva do sono

Purpose: To determine the frequency of glaucoma and evaluate the behavior of 24-hour intraocular pressure in patients with the obstructive sleep apnea syndrome (OSAS). Methods: Eleven consecutive patients with OSAS, diagnosed by polysonography, were avaliated in a cross-sectional study. Demographic data were analyzed: age, sex, race/color, weight, height and associated diseases. The patients were submitted to complete ophthalmologic examination, including the visual field, as well as to 24-hour intra-ocular pressure (IOP) evaluation by an applanation tonometer at 9h, 12h, 15h, 18h, 24h and 6h in the lying and sitting positions. The diagnostic criterion for glaucoma was alteration of the visual field (VF) compatible with glaucoma and one or more of the following alterations: cup-disc ratio >= 0.7, hemorrhage, wedge-shaped defect, bayonet-shaped vessels, Hoyt's sign, asymmetry > than 0.2 between cup/disc ratio of the eyes. The angle should be opened without alterations. Results: 9 (82%) of 11 patients showed glaucoma or were suspected to have glaucoma, 9% of which exhibited normal tension glaucoma and 73% were suspected to have glaucoma for presenting alterations in the optic nerve or ocular hypertension. The mean for the IOP values of the 11 patients was observed to be the highest at 6 o'clock, when they were lying down. Variations of IOP >= 5 mmHg occurred in 7 (64%) of the patients, and variations of up to 14 mmHg and IOP peaks of up to 32 mmHg were observed. Conclusion: OSAS may be an important risk factor for the development of glaucoma, particularly that of normal tension glaucoma. Patients with OSAS must be referred to an ophthalmologist and those professionals must be attentive to the association of sleep disorders in patients with open-angle glaucoma.

Cirurgia de catarata e glaucoma

Trabalho Final do Curso de Mestrado Integrado em Medicina, Faculdade de Medicina, Universidade de Lisboa, 2014

Macrodisco y glaucoma en individuos estudiados con tomografía óptica coherente

Introducción: El glaucoma representa la tercera causa de ceguera a nivel mundial y un diagnóstico oportuno requiere evaluar la excavación del nervio óptico que está relacionada con el área del mismo. Existen reportes de áreas grandes (macrodiscos) que pueden ser protectoras, mientras otros las asocian a susceptibilidad para glaucoma. Objetivo: Establecer si existe asociación entre macrodisco y glaucoma en individuos estudiados con Tomografía Optica Coherente (OCT ) en la Fundación Oftalmológica Nacional. Métodos: Estudio transversal de asociación que incluyó 25 ojos con glaucoma primario de ángulo abierto y 74 ojos sanos. A cada individuo se realizó examen oftalmológico, campo visual computarizado y OCT de nervio óptico. Se compararon por grupos áreas de disco óptico y número de macrodiscos, definidos según Jonas como un área de la media más dos desviaciones estándar y según Adabache como área ≥3.03 mm2 quien evaluó población Mexicana. Resultados: El área promedio de disco óptico fue 2,78 y 2,80 mm2 glaucoma Vs. sanos. De acuerdo al criterio de Jonas, se observó un macrodisco en el grupo sanos y según criterio de Adabache se encontraron ocho y veinticinco macrodiscos glaucoma Vs. sanos. (OR=0,92 IC95%=0.35 – 2.43). Discusión: No hubo diferencia significativa (P=0.870) en el área de disco entre los dos grupos y el porcentaje de macrodiscos para los dos grupos fue similar, aunque el bajo número de éstos no permitió concluir en términos estadísticos sobre la presencia de macrodisco y glaucoma.

Análise Estrutural do Segmento Anterior por Tomografia de Coerência Ótica no Glaucoma Congénito Primário

Objectivo: Analisar a morfologia do segmento anterior por tomografia de coerência ótica de segmento anterior (OCT-SA) em crianças com glaucoma congénito primário (GCP). Material e métodos: Realizou-se um estudo caso-controlo, prospetivo, em crianças com GCP e em crianças sem glaucoma (grupo controlo), seguidas em Consulta de Oftalmologia Pediátrica do Hospital Dona Estefânia, Centro Hospitalar de Lisboa Central. Efectuou-se avaliação oftalmológica completa e OCT-SA utilizando o protocolo A C biometry. Resultados: O estudo incluiu 27 olhos (17 crianças com OCP) e 22 olhos (11 crianças sem glaucoma). Detetaram-se valores significativamente superiores de profundidade central e largura da câmara anterior (CA) (p<0,001) e maiores distâncias de abertura do ângulo a 500 CP<0,001) e 750µm (p=0,00 l), áreas de espaço irido-trabecular a 500 e 750µm (p<0,001) e áreas do recesso do ângulo a 500 (p<0,00l) e 750µm (p=0,001), no grupo GCP. A espessura da íris foi significativamente mais fina a 500µm do ângulo (p=0,011), no centro da íris (p<0,001) e na região mais espessa da mesma (p=0,001) no grupo GCP, assim como o comprimento da íris foi superior (p<0,001). A largura de CA e a acuidade visual (logMAR) apresentam correlação positiva (r=0,688; p<0,001). Outros achados morfológicos: anteriorização e hipoplasia da íris, alteração da morfologia do ângulo no local de intervenção cirúrgica (goniotomia, trabeculotornia, trabeculectomia, válvula de Ahmed). Conclusão: Este primeiro estudo em crianças com GCP sugere que a OCT-SA é de aquisição relativamente fácil, poderá ajudar no seguimento clínico e cirúrgico e ser útil como fator prognóstico destes doentes.

Abordagem multidisciplinar do glaucoma congénito primário : caso clínico

Trabalho Final do Curso de Mestrado Integrado em Medicina, Faculdade de Medicina, Universidade de Lisboa, 2014

Patient education in glaucoma: what do patients know about glaucoma?

PURPOSE: To evaluate the knowledge glaucoma patients have about their disease and its treatment. METHODS: One hundred and eighty-three patients were interviewed at the Glaucoma Service of Wills Eye Hospital (Philadelphia, USA, Group 1) and 100 at the Glaucoma Service of University of Campinas (Campinas, Brazil, Group 2). An informal, relaxed atmosphere was created by the interviewer before asking a list of 18 open-ended questions. RESULTS: In Group 1, 44% of the 183 patients did not have an acceptable idea about what glaucoma is, 30% did not know the purpose of the medications they were taking, 47% were not aware of what was an average intraocular pressure, and 45% did not understand why visual fields were examined. In Group 2, 54% gave unsatisfactory answers to the question What is glaucoma?, 54% did not know the purpose of the medications they were taking, 80% were not aware of what was an average intraocular pressure, and 94% did not understand why visual fields were examined (p<0.001). Linear regression analysis demonstrated that level of education was positively correlated to knowledge about glaucoma in both groups (r=0.65, p=0.001). CONCLUSION: This study showed that patients' knowledge about glaucoma varies greatly, and that in an urban, American setting, around one third of the patients have minimal understanding, whereas in an urban setting in Brazil around two thirds of patients were lacking basic information about glaucoma. Innovative and effective methods are needed to correct this situation.

The need for artificial tears in glaucoma patients: a comparative, retrospective study

PURPOSE: To evaluate the need for artificial tears by glaucoma patients under topical hypotensive treatment and to identify risk factors associated with it. METHODS: The charts of 175 glaucoma patients under medical treatment and 175 age-matched controls were reviewed. Age, gender, use of artificial tears, number of glaucoma medications used, and duration of treatment were recorded. RESULTS: Significantly more glaucoma patients (n=92; 52.6%) used artificial tears compared to age-matched controls (n=31; 17.7%) (p<0.001). Significantly more females (n=81; 39%) than males (n=42; 28.9%) used artificial tears (p=0.036). When the whole population was analyzed, female gender (OR=1.63) and the presence of glaucoma (OR= 5.14) were risk factors for the use of artificial tears (p<0.05). When the glaucoma population was analyzed, female gender (OR=2.57), number of medications >2 (OR=1.92), and duration of treatment >5 years (OR=2.93) were risk factors for the use of artificial tears (p<0.05). CONCLUSIONS: Topical treatment with antiglaucoma medication is a risk factor for the use of artificial tears. Female gender and long-term treatment of glaucoma with two or more medications were aggravating factors for the need for artificial tears.

Sensitivity and specificity of machine learning classifiers for glaucoma diagnosis using Spectral Domain OCT and standard automated perimetry

PURPOSE: To evaluate the sensitivity and specificity of machine learning classifiers (MLCs) for glaucoma diagnosis using Spectral Domain OCT (SD-OCT) and standard automated perimetry (SAP). METHODS: Observational cross-sectional study. Sixty two glaucoma patients and 48 healthy individuals were included. All patients underwent a complete ophthalmologic examination, achromatic standard automated perimetry (SAP) and retinal nerve fiber layer (RNFL) imaging with SD-OCT (Cirrus HD-OCT; Carl Zeiss Meditec Inc., Dublin, California). Receiver operating characteristic (ROC) curves were obtained for all SD-OCT parameters and global indices of SAP. Subsequently, the following MLCs were tested using parameters from the SD-OCT and SAP: Bagging (BAG), Naive-Bayes (NB), Multilayer Perceptron (MLP), Radial Basis Function (RBF), Random Forest (RAN), Ensemble Selection (ENS), Classification Tree (CTREE), Ada Boost M1(ADA),Support Vector Machine Linear (SVML) and Support Vector Machine Gaussian (SVMG). Areas under the receiver operating characteristic curves (aROC) obtained for isolated SAP and OCT parameters were compared with MLCs using OCT+SAP data. RESULTS: Combining OCT and SAP data, MLCs' aROCs varied from 0.777(CTREE) to 0.946 (RAN).The best OCT+SAP aROC obtained with RAN (0.946) was significantly larger the best single OCT parameter (p<0.05), but was not significantly different from the aROC obtained with the best single SAP parameter (p=0.19). CONCLUSION: Machine learning classifiers trained on OCT and SAP data can successfully discriminate between healthy and glaucomatous eyes. The combination of OCT and SAP measurements improved the diagnostic accuracy compared with OCT data alone.

Mercado aberto : um estudo da implantação e funcionamento no caso brasileiro

O OBJETIVO PRINCIPAL DO TRABALHO É DEMONSTRAR QUE A INTERFERÊNCIA GOVERNAMENTAL, VIA PROMULGAÇÃO DE LEIS (REGULAMENTAÇÃO DO MERCADO SECUNDÁRIO DE TÍTULOS, BENEFICIOU SOBEJAMENTE AS GRANDES EMPRESAS: BANCOS COMERCIAIS, EM DETRIMENTO DAS PEQUENAS: SOCIEDADES CORRETORAS E DISTRIBUIDORAS. PARA ATINGIR ESTE FIM, A OBRA INICIA-SE COM UM ESTUDO DE CRLVO MAIS LONGO: O FINANCIAMENTO DOS GASTOS DO GOVERNO, COM ESPECIAL LUSTRE NOS IMPOSTOS, PROCURANDO LEVANTAR OS MOTIVOS DA UTILIZAÇÃO DE OUTRAS FONTES DE CARREAMENTO DE RECURSOS PARA O FINANCIAMENTO DOS GASTOS DO SETOR GOVERNO E COMO ISSO SE PROCESSOU: O SANEAMENTO DA DÍVIDA PÓBLICA FEDERAL INTERNA, POSSIBILITANDO O LANÇAMENTO DE NOVOS PAPÉIS (ORTN E LTN). AS FORMAS CLÁSSICAS DE CONTROLE DA QUANTIDADE DE MOEDA EXISTENTE NO SISTEMA ECONÔMICO: O REDESCONTO E O COMPULSÓRIO. O MERCADO ABERTO. O QUE É MERCADO ABERTO (" OPEN MARKET"). O QUE SÃO OPERAÇOES DE MERCADO ABERTO - SUA IMPORTÂNCIA PARA O CONTROLE DA LIQUIDEZ. OS TÍTULOS CIRCULANTES NO MERCADO. O FUNCIONAMENTO DO MERCADO PRIMÁRIO (COLOCAÇÃO PELO MECANISMO DE LEILÃO. A PARTICIPAÇÃO DOS "DEALERS". AS OPERAÇOES DO MERCADO SECUNDÁRIO DE TÍTULOS: A FINAL, A PREÇO DE MERCADO, A PREÇO FIXO. A RESOLUÇÃO NG 366, DE 09.04.76 E A INSTITUIÇÃO DAS CARTAS DE RECOMPRA PARA AS OPERAÇÕES A PREÇO FIXO. O QUE SÃO E QUAIS OS TIPOS DE COMPROMISSO. A SEGMENTAÇÃO LEGAL DO MERCADO. A NECESSIDADE DE HABILITAÇÃO. POSSIBILIDADES DE ATUAÇÃO E TIPOS POSSÍVEIS DE COMPROMISSO. LIMITES. O TRATAMENTO DIFERENCIADO DE ACORDO COM O CAPITAL. A PROIBIÇÃO DE ATUAÇÃO EM OPERAÇÕES DE GRANDE RISCO. A CRIAÇÃO DE MERCADOS CATIVOS PARA OS TÍTULOS DE EMISSÃO FEDERAL. A ADAPTAÇÃO GRADATIVA. A PARTE FINAL FICA POR CONTA DOS DADOS E GRÁFICOS QUE COMPROVAM A DIMINUIÇÃO PERCENTUAL DA PARTICIPAÇÃO DAS PEQUENAS EMPRESAS NO MERCADO SECUNDÁRIO DE PAPÉIS, COM INCLUSÃO DE APÊNDICE DE LEGISLAÇÃO CONSULTADA.

Desenvolvimento de um rastreador solar do tipo polar com ajuste do ângulo de inclinação

The use of solar energy for electricity generation has shown a growing interest in recent years. Generally, the conversion of solar energy into electricity is made by PV modules installed on fixed structures, with slope determined by the latitude of the installation site. In this sense, the use of mobile structures with solar tracking, has enabled increased production of the generated energy. However, the performance of these structures depends on the type of tracker and the position control used. In this work, it is proposed position control a strategy applied for a solar tracker, which will be installed in Laboratory of Power Electronics and Renewable Energy (LEPER), located in the Federal University of Rio Grande do Norte (UFRN). The tracker system is of polar type with daily positioning east-west and tilt angle manual adjustment in the seasonal periods, from north to south

Estudo da topologia de redes de conexão funcional no córtex sensorial primário e hipocampo durante o sono de ondas lentas

Complex network analysis is a powerful tool into research of complex systems like brain networks. This work aims to describe the topological changes in neural functional connectivity networks of neocortex and hippocampus during slow-wave sleep (SWS) in animals submited to a novel experience exposure. Slow-wave sleep is an important sleep stage where occurs reverberations of electrical activities patterns of wakeness, playing a fundamental role in memory consolidation. Although its importance there s a lack of studies that characterize the topological dynamical of functional connectivity networks during that sleep stage. There s no studies that describe the topological modifications that novel exposure leads to this networks. We have observed that several topological properties have been modified after novel exposure and this modification remains for a long time. Major part of this changes in topological properties by novel exposure are related to fault tolerance

Centros subcorticais dos sistemas visual primário e óptico acessório no mocó (kerodon rupestris): caracterização pela projeção retiniana e citoarquitetura.

The primary and accessory optic systems comprise two set of retinorecipient neural clusters. In this study, these visual related centers in the rock cavy were evaluated by using the retinal innervations pattern and Nissl staining cytoarchigtecture. After unilateral intraocular injection of cholera toxin B subunit and immunohistochemical reaction of coronal and sagittal sections from the diencephalon and midbrain region of rock cavy. Three subcortical centres of primary visual system were identified, superior colliculus, lateral geniculate complex and pretectal complex. The lateral geniculate complex is formed by a series of nuclei receiving direct visual information from the retina, dorsal lateral geniculate nucleus, intergeniculate leaflet and ventral lateral geniculate nucleus. The pretectal complex is formed by series of pretectal nuclei, medial pretectal nucleus, olivary pretectal nucleus, posterior pretectal nucleus, nucleus of the optic tract and anterior pretectal nucleus. In the accessory optic system, retinal terminals were observed in the dorsal terminal, lateral terminal and medial terminal nuclei as well as in the interstitial nucleus of the superior fasciculus, posterior fibres. All retinorecipient nuclei received bilateral input, with a contralateral predominance. This is the first study of this nature in the rock cavy and the results are compared with the data obtained for other species. The investigation represents a contribution to the knowledge regarding the organization of visual optic systems in relation to the biology of species.

Atividade multimodal no córtex sensorial primário de ratos.

The currently accepted model of sensory processing states that different senses are processed in parallel, and that the activity of specific cortical regions define the sensorial modality perceived by the subject. In this work we used chronic multielectrode extracellular recordings to investigate to which extent neurons in the visual and tactile primary cortices (V1 and S1) of anesthetized rats would respond to sensory modalities not traditionaly associated with these cortices. Visual stimulation yielded 87% of responsive neurons in V1, while 82% of S1 neurons responded to tactile stimulation. In the same stimulation sessions, we found 23% of V1 neurons responding to tactile stimuli and 22% of S1 neurons responding to visual stimuli. Our data supports an increasing body of evidence that indicates the existence multimodal processing in primary sensory cortices. Our data challenge the unimodal sensory processing paradigm, and suggest the need of a reinterpretation of the currently accepted model of cortical hierarchy.

Controlador adaptativo por modelo de referência e estrutura variável aplicado ao controle de ângulo de carga e fluxo de campo de um gerador síncrono

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior