995 resultados para Orbital velocities
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PURPOSE: To describe three cases of orbital tuberculosis, with their clinical characteristics and respective diagnostic procedures, showing the importance of histopathology for the correct diagnosis. PATIENTS AND METHODS: Three patients diagnosed and treated for orbital tuberculosis, in the "Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo" during the years of 1999 and 2001. RESULTS: All of the patients were female and referred a chronic evolution of swelling of one eyelid associated or not with other symptoms. They had not HIV infection. Two of them had positive epidemiology for tuberculosis. However, the search for systemic evidence of the disease and staining for bacilli (Ziehl-Neelsen method) were negative in all three patients. In all the cases, only the biopsy with immunohistochemical analysis could confirm the diagnosis. COMMENTS: Orbital involvement is a rare ocular manifestation of tuberculosis. Even in a tertiary hospital, few cases, if any, are diagnosed per year. However, the global incidence and prevalence of M. tuberculosis infections is not under control yet, and it has been a serious public health problem. Thus, one must be aware of the possibility of tuberculosis among the orbital diseases.
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Exenteration of the orbit is a disfiguring and destructive procedure; it is generally performed for orbital malignancies and often provides a significant reconstructive challenge. Our purpose was to evaluate the clinical indications for orbital exenteration in a tertiary referral center and to assess the reconstructive options employed. A retrospective nonrandomized analysis was performed, selecting all patients undergoing orbital exenteration over a 5-year period, between January 2005 and January 2010. Patient demographics, tumor characteristics, and reconstructive techniques used were evaluated. Twenty patients with a mean age of 76.5 years underwent total orbital exenteration. Basal cell carcinoma was the main operative indication (45%), followed by squamous cell carcinoma (15%). Reconstructive techniques included cover of the raw orbital cavity with a temporal muscular flap in all cases followed with split skin grafting (25%), bilaterally pedicle V-Y advancement flap (10%) and a fasciocutaneous island flap of the retroauricular region (65%). Twenty percent of patients had local complications and all were treated in a satisfactory fashion. Eyelid skin tumors remain an important cause of orbital exenteration. Temporal muscle flap is a reliable and stable reconstructive solution after orbital exenteration and additional aid is supplied with skin grafts or local flaps. This technique ensures a good aesthetic outcome and better situation for later complementary treatments and minimal associated donor site morbidity.
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PURPOSE: To report a series of 73 patients with endocrine exophthalmos treated by removal of orbital fat using the transpalpebral approach during the period 1989 to 1999. METHODS: The operation was performed according to the technique described by Olivari. Aesthetic analysis was done preoperatively and postoperatively (more than 6 months after surgery). The number of complications was also observed. RESULTS: The average volume of resected fat was approximately 7.6 mL per orbit. No major complication was observed. In 9 patients with epiphora, all improved. One patient developed postoperative diplopia and 5 complained of temporary diplopia. Appearance improved in 62 patients (85%). CONCLUSION: Surgical removal of orbital fat associated with endocrine exophthalmos provides consistent improvement in appearance with a low rate of complications. Additional procedures may be indicated to improve the cosmetic outcome.
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A técnica de análise derivativa de dados espectrais foi usada para estudar a variação dos constituintes opticamente ativos (COAs) na água, por meio de dados de campo e de imagens do sensor orbital Hyperion/EO-1. A imagem Hyperion usada neste estudo foi adquirida no dia 23 de junho de 2005, no final do período de cheia. Uma campanha de campo foi realizada entre 23 e 29 de junho de 2005, para coletar dados espectrais e limnológicos in situ. A imagem foi pré-processada visando eliminar faixas de pixels anômalos e convertida de valores de radiância para reflectância de superfície, portanto, corrigidos dos efeitos de absorção e espalhamento atmosféricos. Uma análise da correlação foi realizada para examinar a associação da reflectância e de sua primeira derivada espectral com as concentrações dos COAs. Melhores resultados foram obtidos após a diferenciação dos espectros, o que ajudou a reduzir a influência de efeitos indesejáveis, provindos de diferentes fontes de radiância, sobre as medidas de reflectância da superfície da água realizadas em ambos os níveis de aquisição de dados. Por meio de ajustes de regressões empíricas, considerando o conjunto de dados Hyperion, a primeira derivada espectral em 711 nm explicou 86% da variação da concentração de sedimentos inorgânicos em suspensão (µg.l-1) e a primeira derivada espectral em 691 nm explicou 73% da variação na concentração da clorofila-alfa (µg.l-1). As relações de regressão foram não-lineares, pois, em geral, as águas que se misturam na planície de inundação Amazônica se tornam opticamente complexas. A técnica de análise derivativa hiperespectral demonstrou potenciais para mapear a composição dessas águas.
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This chapter describes the how the vector of coordinates are defined in the formulation of spatial multibody systems. For this purpose, the translational motion is described in terms of Cartesian coordinates, while rotational motion is specified using the technique of Euler parameters. This approach avoids the computational difficulties associated with the singularities in the case of using Euler angles or Bryant angles. Moreover, the formulation of the velocities vector and accelerations vector is presented and analyzed here. These two sets of vectors are defined in terms of translational and rotational coordinates.
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OBJECTIVE: Doppler tissue imaging (DTI) enables the study of the velocity of contraction and relaxation of myocardial segments. We established standards for the peak velocity of the different myocardial segments of the left ventricle in systole and diastole, and correlated them with the electrocardiogram. METHODS: We studied 35 healthy individuals (27 were male) with ages ranging from 12 to 59 years (32.9 ± 10.6). Systolic and diastolic peak velocities were assessed by Doppler tissue imaging in 12 segments of the left ventricle, establishing their mean values and the temporal correlation with the cardiac cycle. RESULTS: The means (and standard deviation) of the peak velocities in the basal, medial, and apical regions (of the septal, anterior, lateral, and posterior left ventricle walls) were respectively, in cm/s, 7.35(1.64), 5.26(1.88), and 3.33(1.58) in systole and 10.56(2.34), 7.92(2.37), and 3.98(1.64) in diastole. The mean time in which systolic peak velocity was recorded was 131.59ms (±19.12ms), and diastolic was 459.18ms (±18.13ms) based on the peak of the R wave of the electrocardiogram. CONCLUSION: In healthy individuals, maximum left ventricle segment velocities decreased from the bases to the ventricular apex, with certain proportionality between contraction and relaxation (P<0.05). The use of Doppler tissue imaging may be very helpful in detecting early alterations in ventricular contraction and relaxation.
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PURPOSE: Orbital wall fracture may occur during endoscopic sinus surgery, resulting in oculomotor disorders. We report the management of four cases presenting with this surgical complication. METHODS: A non-comparative observational retrospective study was carried out on four patients presenting with diplopia after endoscopic ethmoidal sinus surgery. All patients underwent full ophthalmologic and orthoptic examination as well as orbital imaging. RESULTS: All four patients presented with diplopia secondary to a medial rectus lesion confirmed by orbital imaging. A large horizontal deviation as well as limitation of adduction was present in all cases. Surgical management consisted of conventional recession-resection procedures in three cases and muscle transposition in one patient. A useful field of binocular single vision was restored in two of the four patients. CONCLUSION: Orbital injury may occur during endoscopic sinus surgery and cause diplopia, usually secondary to medial rectus involvement due to the proximity of this muscle to the lamina papyracea of the ethmoid bone. Surgical management is based on orbital imaging, duration of the lesion, evaluation of anterior segment vasculature, results of forced duction testing and intraoperative findings. In most cases, treatment is aimed at the symptoms rather than the cause, and the functional prognosis remains guarded.
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BACKGROUND: Subconjunctival orbital fat prolapse is a benign entity characterized by orbital fat herniation through a dehiscence in Tenon's capsule, usually between the superior and lateral recti muscles. It is often associated with ocular trauma or surgery, although spontaneous cases have also been reported with a predilection for obese individuals. PATIENTS AND METHODS: A retrospective study of four subconjunctival orbital-fat prolapse cases with no history of ocular surgery or trauma was performed. A trans-conjunctival surgical approach with Tenon's capsule repair was offered to all subjects. Differential diagnosis is discussed. RESULTS: The diagnosis of subconjunctival orbital fat prolapse was confirmed in all cases by histopathological examination. Functional and aesthetic postoperative results were excellent, with no recurrences during follow-up, for all cases. CONCLUSIONS: Although rare, subconjunctival orbital fat prolapse should be recognized. Surgical management offers excellent results.
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PURPOSE: The purpose of this paper is to present our data and to provide some conclusions about the attitude that has to be chosen when metastasis of the orbit is suspected. PATIENTS AND METHODS: Between 1965 and 1994, 571 patients with non-traumatic orbital diseases were controlled in the department of ophthalmology of Lausanne. Thirty-four cases of metastasis of the orbit were selected, that is 24 females and 10 males, aged from 1 to 81 years. Tumors of the breast are the most frequent origin of this metastasis, followed by cutaneous melanomas and pulmonary tumors. Orbital metastasis was the first sign of a malignant process in 7 patients. The histologic diagnosis was confirmed in 15 patients. The type of treatment is presented herein and the follow-up of more than half of the cases is given. RESULTS AND CONCLUSION: Orbital metastasis can develop after a long time in patients who were previously treated for malignant tumors. In several cases, orbital metastasis was the first sign of a malignant process which starts to become general. This diagnosis has to be taken into account when a patient was treated earlier for a malignant tumor, and it is reasonable to propose a biopsy or an excision biopsy in every orbital pathology which was not confirmed by clinical or paraclinical investigations.
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The performance of the SAOP potential for the calculation of NMR chemical shifts was evaluated. SAOP results show considerable improvement with respect to previous potentials, like VWN or BP86, at least for the carbon, nitrogen, oxygen, and fluorine chemical shifts. Furthermore, a few NMR calculations carried out on third period atoms (S, P, and Cl) improved when using the SAOP potential
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BACKGROUND: Diplopia related to neurosurgical procedures is often consecutive to oculomotor nerve lesions. We hereby report an oculomotor dysfunction secondary to an orbital roof effraction and its treatment. HISTORY AND SIGNS: Following surgery for a left anterior communicating artery aneurysm, a 45-year-old woman reported vertical diplopia associated with a left orbital hematoma. The diagnosis of third cranial nerve palsy was excluded by orbital imaging which revealed an orbital roof defect with incarceration of the levator palpebrae and superior rectus. THERAPY AND OUTCOME: As neurosurgeons advised against muscle adhesiolysis, diplopia was corrected by a two-step procedure on the oculomotor muscles. We first corrected horizontal and torsional deviations by operating on the healthy eye, before correcting the vertical deviation on the fellow eye. This two-step extraocular muscle surgery allowed restoration of binocular single vision in a useful field of gaze. CONCLUSIONS: Diplopia can occur as a rare orbital complication during neurosurgical procedures. Surgery of extraocular muscles can provide good functional results