993 resultados para pressão intraocular
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PURPOSE To report the incidence of anterior capsule contraction syndrome (ACCS) and to present a novel minimally invasive bimanual technique for anterior segment revision surgery associated with ACCS with anterior flexion of the intraocular lens haptics. METHODS A consecutive cohort of 268 eyes of 161 patients undergoing phacoemulsification and implantation of the same type of hydrophilic acrylic aspheric intraocular lens cohort were analysed and a novel technique of minimally invasive bimanual technique for anterior segment revision surgery is described. RESULTS We identified four eyes (1.5%) of three patients with advanced ACCS. Successful restoration of a clear visual axis with minimal induction of astigmatism and rapid visual rehabilitation was achieved in all four cases. CONCLUSION This technique is a safe and minimally invasive alternative to laser or vitrector-cut capsulotomy to restore a clear visual axis. In cases of advanced ACCS, it offers the option for haptic reposition or amputation.
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PURPOSE External beam radiation therapy is currently considered the most common treatment modality for intraocular tumors. Localization of the tumor and efficient compensation of tumor misalignment with respect to the radiation beam are crucial. According to the state of the art procedure, localization of the target volume is indirectly performed by the invasive surgical implantation of radiopaque clips or is limited to positioning the head using stereoscopic radiographies. This work represents a proof-of-concept for direct and noninvasive tumor referencing based on anterior eye topography acquired using optical coherence tomography (OCT). METHODS A prototype of a head-mounted device has been developed for automatic monitoring of tumor position and orientation in the isocentric reference frame for LINAC based treatment of intraocular tumors. Noninvasive tumor referencing is performed with six degrees of freedom based on anterior eye topography acquired using OCT and registration of a statistical eye model. The proposed prototype was tested based on enucleated pig eyes and registration accuracy was measured by comparison of the resulting transformation with tilt and torsion angles manually induced using a custom-made test bench. RESULTS Validation based on 12 enucleated pig eyes revealed an overall average registration error of 0.26 ± 0.08° in 87 ± 0.7 ms for tilting and 0.52 ± 0.03° in 94 ± 1.4 ms for torsion. Furthermore, dependency of sampling density on mean registration error was quantitatively assessed. CONCLUSIONS The tumor referencing method presented in combination with the statistical eye model introduced in the past has the potential to enable noninvasive treatment and may improve quality, efficacy, and flexibility of external beam radiotherapy of intraocular tumors.
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[von] Ferdinando Lionti
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[von] Ferndinando Lionti
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PURPOSE To observe changes in fundus autofluorescence 2 years after implantation of blue light-filtering (yellow-tinted) and ultraviolet light-filtering (colorless) intraocular lenses (IOLs). SETTING Department of Ophthalmology and Visual Science, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan, and the Department of Ophthalmology, University of Bern, Bern, Switzerland. DESIGN Prospective comparative observational study. METHODS Patients were enrolled who had cataract surgery with implantation of a yellow-tinted or colorless IOL and for whom images were obtained on which the fundus autofluorescence was measurable using the Heidelberg Retina Angiogram 2 postoperatively. The fundus autofluorescence in the images was classified into 8 abnormal patterns based on the classification of the International Fundus Autofluorescence Classification Group, The presence of normal fundus autofluorescence, geographic atrophy, and wet age-related macular degeneration (AMD) also was recorded. The fundus findings at baseline and 2 years postoperatively were compared. RESULTS Fifty-two eyes with a yellow-tinted IOL and 79 eyes with a colorless IOL were included. Abnormal fundus autofluorescence did not develop or increase in the yellow-tinted IOL group; however, progressive abnormal fundus autofluorescence developed or increased in 12 eyes (15.2%) in the colorless IOL group (P = .0016). New drusen, geographic atrophy, and choroidal neovascularization were observed mainly in the colorless IOL group. The incidence of AMD was statistically significantly higher in the colorless IOL group (P = .042). CONCLUSIONS Two years after cataract surgery, significant differences were seen in the progression of abnormal fundus autofluorescence between the 2 groups. The incidence of AMD was lower in eyes with a yellow-tinted IOL. FINANCIAL DISCLOSURE No author has a financial or proprietary interest in any material or method mentioned.
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Vitrectomy is a standard ophthalmic procedure to remove the vitreous body from the eye. The biomechanics of the vitreous affects its duration (by changing the removal rate) and the mechanical forces transmitted via the vitreous on the surrounding tissues during the procedure. Biomechanical characterization of the vitreous is essential for optimizing the design and control of instruments that operate within the vitreous for improved precision, safety, and efficacy. The measurements are carried out using a magnetic microprobe inserted into the vitreous, a method known as magnetic microrheology. The location of the probe is tracked by a microscope/camera while magnetic forces are exerted wirelessly by applied magnetic fields. In this work, in vitro artificial vitreous, ex vivo human vitreous and ex vivo porcine vitreous were characterized. In addition, in vivo rabbit measurements were performed using a suturelessly injected probe. Measurements indicate that viscoelasticity parameters of the ex vivo human vitreous are an order of magnitude different from those of the ex vivo porcine vitreous. The in vivo intra-operative measurements show typical viscoelastic behavior of the vitreous with a lower compliance than the ex vivo measurements. The results of the magnetic microrheology measurements were validated with those obtained by a standard atomic force microscopy (AFM) method and in vitro artificial vitreous. This method allows minimally-invasive characterization of localized mechanical properties of the vitreous in vitro, ex vivo, and in vivo. A better understanding of the characteristics of the vitreous can lead to improvements in treatments concerning vitreal manipulation such as vitrectomy.
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Este estudo investiga a importância do exercício físico na prevençao de Doenças Crônicas Nao Transmissíveis. Seu objetivo é verificar o efeito de 16 semanas de exercícios físicos no perfil lipídico e pressao arterial. O grupo de estudo foi composto por 12 voluntários, com faixa etária de 40 a 60 anos, com média de colesterol total e LDL insignificantemente acima dos valores limítrofe e pré-hipertensos. Os indivíduos foram submetidos á avaliaçao médica; análise laboratorial; teste físico e 16 semanas de treinamento físico com frequência de três vezes por semana. Todos os procedimentos foram repedidos ao final. Houve reduçao significativa do Indice de Massa Corporal, Colesterol LDL, Pressao Arterial Diastólica e aumento da glicemia e do desempenho físico. Nao se modificaram o Colesterol Total, Colesterol HDL e Triglicerídeos. O programa de exercícios, mesmo sem o controle de dieta, foi suficiente para provocar as alteraçoes descritas do perfil lipídico, comprovando sua importância na prevençao de doenças cardíacas
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Este estudo investiga a importância do exercício físico na prevençao de Doenças Crônicas Nao Transmissíveis. Seu objetivo é verificar o efeito de 16 semanas de exercícios físicos no perfil lipídico e pressao arterial. O grupo de estudo foi composto por 12 voluntários, com faixa etária de 40 a 60 anos, com média de colesterol total e LDL insignificantemente acima dos valores limítrofe e pré-hipertensos. Os indivíduos foram submetidos á avaliaçao médica; análise laboratorial; teste físico e 16 semanas de treinamento físico com frequência de três vezes por semana. Todos os procedimentos foram repedidos ao final. Houve reduçao significativa do Indice de Massa Corporal, Colesterol LDL, Pressao Arterial Diastólica e aumento da glicemia e do desempenho físico. Nao se modificaram o Colesterol Total, Colesterol HDL e Triglicerídeos. O programa de exercícios, mesmo sem o controle de dieta, foi suficiente para provocar as alteraçoes descritas do perfil lipídico, comprovando sua importância na prevençao de doenças cardíacas
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Este estudo investiga a importância do exercício físico na prevençao de Doenças Crônicas Nao Transmissíveis. Seu objetivo é verificar o efeito de 16 semanas de exercícios físicos no perfil lipídico e pressao arterial. O grupo de estudo foi composto por 12 voluntários, com faixa etária de 40 a 60 anos, com média de colesterol total e LDL insignificantemente acima dos valores limítrofe e pré-hipertensos. Os indivíduos foram submetidos á avaliaçao médica; análise laboratorial; teste físico e 16 semanas de treinamento físico com frequência de três vezes por semana. Todos os procedimentos foram repedidos ao final. Houve reduçao significativa do Indice de Massa Corporal, Colesterol LDL, Pressao Arterial Diastólica e aumento da glicemia e do desempenho físico. Nao se modificaram o Colesterol Total, Colesterol HDL e Triglicerídeos. O programa de exercícios, mesmo sem o controle de dieta, foi suficiente para provocar as alteraçoes descritas do perfil lipídico, comprovando sua importância na prevençao de doenças cardíacas