190 resultados para myopia


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When visual information is confined to one object plane, the emmetropization end-point is adjusted in accord with the corresponding incident optical vergence at the eye [Proceedings of the 7th International Conference on Myopia (2000) 113]. We now report the effect of adding extra visual information beyond the target plane. Visual conditions were controlled using a cone-lens system: black Maltese cross targets on white opaque backgrounds (OMX) were attached to the open faces of 2.5 cm translucent cones fitted with either 0, +25 or +40 D imaging lenses. An alternative target (TMX) was made by substituting the opaque target background for a transparent background, which allowed access to visual information beyond the target plane. The imaging devices were applied to 7-day-old chicks and worn for 4 days. Prior to this treatment, on day 2, some chicks underwent ciliary nerve section (CNS) to preclude accommodation. All treatments were monocular. Refractive errors and axial ocular dimensions were measured using retinoscopy and A-scan ultrasonography under halothane anesthesia. Treatment effects were specified as mean ( +/-S.D.) interocular differences. Eyes with the OMX/ + 40 D lens combination remained emmetropic ( +0.73 +/-3.57 D), consistent with the target plane being approximately conjugate with the retina. Switching to the TMX caused a hyperopic shift in refractive error ( + 3.78 +/- 3.41 D). This relative shift towards hyperopia in switching from the OMX to the TMX target also occurred for the other two lens powers. Thus, the OMX/ + 25 D lens induced myopia ( - 7.00 +/-5.88 D), corresponding to the imposed hyperopic defocus (target plane now imaged behind the retina), and switching to the TMX resulted in a reduction in myopia (-1.73 +/-5.36 D), The OMX/0 D lens combination produced the largest myopic shift, and here, switching to the TMX condition almost eliminated the myopic response (-15.50 +/-6.62 D cf. -0.56 +/-1.24 D). This relative hyperopic shift associated with switching from the OMX to the TMX target was eliminated by CNS surgery. Thus, the two CNS/TMX groups were both more myopic than the equivalent no CNS/TMX groups ( + 40 D lens: -2.66 +/-2.34 D; +25 D lens: -7.97 +/-6.87 D). When the visual information is restricted to one plane, incident optical vergence appears to direct emmetropization. Adding Visual information at other distances produces a shift in the end-point of ernmetropization in the direction of the added information. That these effects are dependent on the integrity of the accommodation system implies that accommodation plays a role in emmetropization and represents the first reported evidence of this kind. Published by Elsevier Science Ltd.

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Corticoteroid-induced glaucoma can result from either topical or systemic corticosteroid use. Compared with adults, the corticosteroid response in children is less well known. The case is reported of a child who developed glaucoma after receiving topical corticosteroids following a scleral re-inforcement procedure. The raised intraocular pressure was controlled after cessation of the corticosteroids and with the use of antiglaucoma therapy. As many forms of cortico-steroids are widely used, children on corticosteroids should have regular intraocular pressure measurements as part of their management.

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ABSTRACT Based on the assumption that earnings persistence has implications for both financial analysis and compensation contracts, the aim of this paper is to investigate the role of earnings persistence assuming that (i) more persistent earnings are likely to be a better input to valuation models and (ii) more persistent earnings are likely to serve as a proxy for long-term market and managerial orientation. The analysis is based on Brazilian listed firms from 1995 to 2013, and while we document strong support for the relevance of earnings persistence in financial analysis and valuation, we fail to document a significant relationship between earnings persistence and long-term value orientation. These results are sensitive to different specifications, and additional results suggest that firms' idiosyncratic risk (total risk) is relevant to explain the focus on short-term outcomes (short-termism) across firms. The main contribution of this paper is to offer empirical evidence for the relevance of accounting numbers in both valuation and contractual theories in an emergent market.

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RESUMO: Neste estudo investigou-se a influência dos meios audiovisuais na tomada de decisão pelos utentes em cirurgias oftalmológicas, especialmente nas cirurgias refractivas. A metodologia escolhida integrou métodos quantitativos e qualitativos, com o objectivo de abranger a máxima amplitude da descrição, explicação e compreensão do objecto a ser investigado. Procura-se evidenciar e analisar sentimentos, motivações e atitudes individuais, como escolhas e tomada de decisão, bem como, perceber a relação entre o processo de comunicação médico / paciente e a tomada de decisão. Foram usados: um questionário, material digital e vídeos com as principais cirurgias refractivas apresentadas aos utentes, com uma amostra de n= 150 participantes do Serviço de Oftalmologia da HOSPOR e SAMS Centro de 01 de Julho 2008 a 28 de Fevereiro de 2009, com a faixa etária de 20 a 80 anos, com diagnóstico escolhido. Os dados recolhidos foram analisados pelo SPSS 18. A fundamentação teórica está baseada no estudo da captação e disfunções no trajecto da imagem, observando-se os componentes da aquisição do conhecimento: sensação, percepção, pensamento, consciência, memória, imaginação, linguagem, informação, bem como bioética, comunicação médica e a tomada de decisão, na qual se valoriza a educação do Utente para decidir. O resultado desta investigação aponta para novos paradigmas nos processos de informação / decisão consciente, indicando a necessidade de se investir na educação e na informação médica humanizada aos utentes para haver maior conhecimento, participação, satisfação e eficácia na terapêutica a ser escolhida. ABSTRACT: This paper analyzes how information and communication technologies, in particular the media of some ophthalmologic surgery, can help better decisions meaning new ways of information and new relationship between doctor and patient. This study investigates how doctors take hold of technological resources and discuss the client`s decision. We used the quantitative and qualitative structured interview of client who are visually impaired, especially myopia / hyperopia / astigmatism, presbyopia and cataract. We used a questionnaire, material and digital videos with the leading refractive surgery presented to the clients, with a sample of n = 150 participants of the Department of Ophthalmology, and SAMS HOSPOR Center from 01 July 2008 to 28 February 2009, with range 20 to 80 years, diagnosed chosen. The data collected were analyzed by SPSS. The theoretical study is based on the capture and routing of image and perception, observing neuro-psycho-social components: sensation, perception, visual perception, consciousness, knowledge, memory, imagination, language, information, bioethics and decision-making, in which values education of user to decide. The result of this research points to new paradigms in information processing / conscious decision, indicating the necessity of investing in education and humane medical information to the Users in order to archive a greater awareness,participation, satisfaction and effectiveness in the treatment to choose.

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Introdução – Na correção de miopias elevadas, a cirurgia por implante de lente intraocular fáquica tem tido progressivamente uma maior adesão em relação à cirurgia por laser. Compara-se a acuidade visual (AV) antes e após a cirurgia implanto-refrativa, verificando-se a efetividade deste método no incremento da visão em miopias elevadas. Metodologia – Foram analisados, retrospetivamente, 70 olhos de 41 pacientes, com miopia elevada, entre os 20 e 50 anos, submetidos a cirurgia implanto-refrativa entre 2009 e 2012. Resultados – Um dia após cirurgia, 42,86% da amostra melhorou a AV, 34,29% manteve e 22,85% diminuiu. Após 30 dias observou-se um aumento generalizado da quantidade de visão, sendo que: 64,29% atingiu os 10/10 de AV, 24,29% alcançou entre 9/10-7/10 e 11,42% entre 6/10-4/10. Conclusão – Comprovou-se a efetividade desta técnica cirúrgica, verificando-se o aumento da AV em 52,86% da amostra.

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Purpose. The purpose of this work was to evaluate the potential of a novel custom-designed rigid gas permeable (RGP) contact lens to modify the relative peripheral refractive error in a sample of myopic patients. Methods. Fifty-two right eyes of 52 myopic patients (mean [TSD] age, 21 [T2] years) with spherical refractive errors ranging from j0.75 to j8.00 diopters (D) and refractive astigmatism of 1.00 D or less were fitted with a novel experimental RGP (ExpRGP) lens designed to create myopic defocus in the peripheral retina. A standard RGP (StdRGP) lens was used as a control in the same eye. The relative peripheral refractive error was measured without the lens and with each of two lenses (StdRGP and ExpRGP) using an open-field autorefractometer from 30 degrees nasal to 30 degrees temporal, in 5-degree steps. The effectiveness of the lens design was evaluated as the amount of relative peripheral refractive error difference induced by the ExpRGP compared with no lens and with StdRGP conditions at 30 degrees in the nasal and temporal (averaged) peripheral visual fields. Results. Experimental RGP lens induced a significant change in relative peripheral refractive error compared with the nolens condition (baseline), beyond the 10 degrees of eccentricity to the nasal and temporal side of the visual field (p G 0.05). The maximum effect was achieved at 30 degrees. Wearing the ExpRGP lens, 60% of the eyes had peripheral myopia exceeding j1.00 D, whereas none of the eyes presented with this feature at baseline. There was no significant correlation (r = 0.04; p = 0.756) between the degree of myopia induced at 30 degrees of eccentricity of the visual field with the ExpRGP lens and the baseline refractive error. Conclusions. Custom-designed RGP contact lenses can generate a significant degree of relative peripheral myopia in myopic patients regardless of their baselin spherical equivalent refractive error.

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Purpose: To evaluate the impact of eye and head rotation in the measurement of peripheral refraction with an open-field autorefractometer in myopic eyes wearing two different center-distance designs of multifocal contact lenses (MFCLs). Methods: Nineteen right eyes from 19 myopic patients (average central M ± SD = −2.67 ± 1.66 D) aged 20–27 years (mean ± SD = 23.2 ± 3.3 years) were evaluated using a Grand-Seiko autorefractometer. Patients were fitted with one multifocal aspheric center-distance contact lens (Biofinity Multifocal D®) and with one multi-concentric MFCL (Acuvue Oasys for Presbyopia). Axial and peripheral refraction were evaluated by eye rotation and by head rotation under naked eye condition and with each MFCL fitted randomly and in independent sessions. Results: For the naked eye, refractive pattern (M, J0 and J45) across the central 60◦ of the horizontal visual field values did not show significant changes measured by rotating the eye or rotating the head (p > 0.05). Similar results were obtained wearing the Biofinity D, for both testing methods, no obtaining significant differences to M, J0 and J45 values (p > 0.05). For Acuvue Oasys for presbyopia, also no differences were found when comparing measurements obtained by eye and head rotation (p > 0.05). Multivariate analysis did not showed a significant interaction between testing method and lens type neither with measuring locations (MANOVA, p > 0.05). There were significant differences in M and J0 values between naked eyes and each MFCL. Conclusion: Measurements of peripheral refraction by rotating the eye or rotating the head in myopic patients wearing dominant design or multi-concentric multifocal silicone hydrogel contact lens are comparable.

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Dissertação de mestrado em Optometria Avançada

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Dissertação de mestrado em Optometria Avançada

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Dissertação de mestrado em Optometria Avançada

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Brittle cornea syndrome (BCS) is an autosomal recessive disorder characterised by extreme corneal thinning and fragility. Corneal rupture can therefore occur either spontaneously or following minimal trauma in affected patients. Two genes, ZNF469 and PRDM5, have now been identified, in which causative pathogenic mutations collectively account for the condition in nearly all patients with BCS ascertained to date. Therefore, effective molecular diagnosis is now available for affected patients, and those at risk of being heterozygous carriers for BCS. We have previously identified mutations in ZNF469 in 14 families (in addition to 6 reported by others in the literature), and in PRDM5 in 8 families (with 1 further family now published by others). Clinical features include extreme corneal thinning with rupture, high myopia, blue sclerae, deafness of mixed aetiology with hypercompliant tympanic membranes, and variable skeletal manifestations. Corneal rupture may be the presenting feature of BCS, and it is possible that this may be incorrectly attributed to non-accidental injury. Mainstays of management include the prevention of ocular rupture by provision of protective polycarbonate spectacles, careful monitoring of visual and auditory function, and assessment for skeletal complications such as developmental dysplasia of the hip. Effective management depends upon appropriate identification of affected individuals, which may be challenging given the phenotypic overlap of BCS with other connective tissue disorders.

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Los déficits y sesgos tanto cognitivos como afectivos han sido fuente creciente de interés en el ámbito de la Neurociéncia de los Trastornos Mentales. En este proyecto, que se inicia en 2004 y finaliza a finales de 2008, se han estudiado los siguientes Trastornos Mentales: Juego Patológico (JP), Trastornos de la Conducta Alimentaria (TCA) y Trastornos Depresivos. En esta memoria nos centraremos en resumir parte de los resultados obtenidos en un estudio sobre JP y toma de decisiones (articulo en revisión y pendiente de aceptación) y otro de funcionamiento ejecutivo en JP y Bulimia Nerviosa (BN) (artículo en prensa). Resumiento el primer estudio los JP (N=32) muestran un proceso de toma de decisiones sesgado por la búsqueda de recompensa en forma de elevada toma de riesgos en comparación con Controles Sanos (CS). También se observan déficits en flexibilidad cognitiva pero no en control inhibitorio entre JP y CS. Los resultados descartan miopía conductual para lo toma de decisiones en JP, pero apuntan a un sesgo cognitivo-afectivo, en el que el control de los impulsos jugaría un papel relevante, en forma de ilusión de control, para los procesos de toma de decisiones con recompensa inmediata pero con castigo diferido, medidos por una prueba de toma de decisiones (IGT ABCD). En el segundo estudio, basándose en las vulnerabilidadades compartidas descritas entre JP y BN se comparó el funcionamiento ejecutivo de mujeres con JP y BN. Tras la administración del WCST y Stroop y ajustando el análisis por edad y educación, las JP mostraron mayor afectación, en concreto mayor porcentaje de errores perservaritvos, menor nivel de respuestas conceptuales y mayor número de ensayos administrados, mientras que el grupo de BN mostró mayor porcentaje de errores no persevarativos. Ambas, mujeres JP y BN mostraron disfunción ejecutiva en relación a los CS pero con diferentes correlatos específcos.

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Purpose:to describe the clinical features in a five generations family segregating autosomal dominant retinitis pigmentosa and to identify the causative gene Patient and Methods:Twenty five individuals of a large five-generation family originating from Western Switzerland were ascertained for phenotypic and genotypic characterization. Ophthalmologic evaluations included color vision testing, Goldman perimetry and digital fundus photography. Some patients had autofluorescence (AF) imaging, ocular coherence tomography (OCT) and ISCEV-standard full-field electroretinography (ERG). Blood samples were collected from 10 affected (4 to 70 years of age) and 15 unaffected members after informed consent. DNA was isolated and exons and intron-exons junctions of known adRP genes were sequenced using a Big Dye sequencing kit 1.1. Results:Age of onset of nightblindness and severity of progression of the disease was variable between members of the family. Some patients had early onset of nightblindess aged 3, others at mid-twenties. Most patients had visual acuity above 0.6 for the first 4 decades. Two older patients still had good vision (0.4) in their seventies. Myopia (range: -2 to -5) was noticed in most affected subjects. Fundus findings showed areas of atrophy along the arcades. The AF imaging showed a large high density ring bilaterally. A T494M change was found in exon 11 of PRPF3 gene. The change segregates with the disease in the family. Conclusion: A mutation in the PRPF3 gene is rare compared with other genes causing ADRP. Although a T494M change has been reported, our family is the first one with a variable expressivity. Mutations in PRPF3 gene can cause a variable phenotype of ADRP unlike the previously described Danish and English families. Our report gives a better understanding as to the phenotype/genotype description of ADRP due to PRPF3 mutation.

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Purpose: To assess the phenotype of patients in a large 3 generation Swiss family with X-linked retinitis pigmentosa (XLRP) due to a novel nonsense mutation Glu20stop in RP2 gene and to correlate with the genotype. Methods: 6 affected patients (1 male, 5 females, age range: 23 - 73 years) were assessed with a complete ophthalmologic examination. All had fundus autofluorescence images, standardised electroretinography, Goldmann visual fields and Optical Coherence Tomography. In addition, medical records of 2 affected male patients were reviewed. Blood sample was taken for molecular analysis. Results: The male patients were severely affected at a young age with early macular involvement. The youngest 23 y old male had also high myopia and vision of less than 0.05 according to Snellen EDTRS chart bilaterally. All 5 female carriers had some degree of rod-cone dystrophy, but no macular involvement. The visual acuity was 1.0 in the younger carriers, while the 73 years old had VA of 0.5. Two females had mild myopia (range -0.75 to -2) and one had anisometropia of 3.5D, with the more severely affected eye being myopic. Three out of 5 female carriers had optic nerve drusen. Conclusions: We report a novel Glu20stop mutation in RP2 gene, which is a rare cause of XLRP. Our description of severe phenotype in male patients with high myopia and early macular atrophy confirms previous reports. Unlike previous reports, all our female carriers had RP, but not macular involvement or high myopia. The identifiable phenotype for RP2-XLRP aids in clinical diagnosis and targeted genetic screening.