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- ItemRestritoAvaliação do potencial patogênico e da aderência de Acanthamoeba spp. em lentes de contato esclerais(Universidade Federal de São Paulo, 2022) Pinto, Larissa Fagundes [UNIFESP]; Freitas, Denise [UNIFESP]; Farah, Ana Luisa Hofling-Lima [UNIFESP]; http://lattes.cnpq.br/7050225867972978; http://lattes.cnpq.br/4036480252471491; http://lattes.cnpq.br/4523473585685940A ceratite por Acanthamoeba é uma infecção corneana grave que tem como principal fator de risco o uso inadequado das lentes de contato. Já é comprovado que espécies do gênero Acanthamoeba spp. são capazes de aderir à superfície de uma grande variedade de lentes disponíveis, contudo, não há relatos na literatura sobre a aderência destas amebas à superfície de lentes de contato esclerais, visto que casos de ceratite associados ao uso destas lentes vêm sendo relatados. Desse modo, esse estudo teve como objetivo averiguar a aderência de diferentes isolados de Acanthamoeba spp. à superfície de lentes esclerais, investigando se o desenho das lentes e diferentes perfis de patogenicidade dos isolados poderiam influenciar poderiam influenciar nesta aderência. Para isso, três isolados de Acanthamoeba spp. foram utilizados: A. polyphaga (ATCC CDC:V062), A. polyphaga (ATCC 30461) e uma amostra clínica (obtida de um caso de ceratite por Acanthamoeba). Também cinco lentes de contato foram testadas: lente silicone-hidrogel (controle), duas lentes esclerais (uma com tratamento de superfície composto por Plasma O2 e a outra por Plasma O2 com Hydra-PEG), e duas lentes planas (com o mesmo tratamento das lentes esclerais respectivamente). As amebas aderidas à superfície das lentes foram observadas por microscopia óptica de luz e microscopia eletrônica de varredura. Também foram avaliadas as superfícies das lentes quanto a possíveis alterações que favorecessem a aderências das amebas. Tanto o isolado clínico quanto o isolado ATCC 30461 exibiram um perfil de exibiram um perfil de patogenicidade superior (crescimento e encistamento) em relação ao isolado ATCC CDC:V062. Ainda, todos os isolados aderiram mais à superfície das lentes esclerais quando comparados às lentes planas. Na microscopia eletrônica de varredura foram observadas dobras na superfície das lentes e, também, notou-se que os isolados apresentavam aspecto ameboide e alongado na superfície das lentes silicone-hidrogel (controle), e arredondado e encolhido na superfície das lentes esclerais. Os dados obtidos neste estudo sugerem que existe uma correlação estatisticamente positiva entre aderência e desenho da lente, assim como de isolados mais virulentos e aderência em lentes esclerais. Novos estudos são necessários visando atenção para o cuidado de lentes esclerais no sentido de retirar Acanthamoeba aderidas em sua superfície, quer seja por ação mecânica ou química. Urge, também, o desenvolvimento de sistemas inovadores de eliminação de parasitas e outros microrganismos das lentes de contato e parafernália.
- ItemAcesso aberto (Open Access)Deformidade corneana em usuário de lente de contato portador de ceratocone: relato de caso(Conselho Brasileiro de Oftalmologia, 1999-12-01) Lipener, César [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)Introduction: Topographical alterations may occur as a secondary result of the use of hard or soft contact lenses. The expression corneal warpage is used to describe the corneal deformities caused by the lenses. Topographical map of initial keratoconus can be very similar to that of a patient with corneal warpage. Purpose: To describe a contact lens wearer with keratoconus who developed corneal warpage symptoms that were diag-nosed and studied by topographies and a series of clinical examinations. Case report: A forty-year-old patient with diagnosis of bilateral keratoconus for 12 years was wearing rigid gas permeable contact lenses since the initial diagnosis. On the first exa-mination in 05/95, it was impossible to determine the RE refraction and keratometry was more than 60.00 D. Topogra-phy was carried out being compatible with keratoconus and a Soper RGP lens was fitted with a 20/70 vision. One year later a control topography showed an increase in the central curve and a flattening of the inferior periphery. The use of contact lenses was interrupted and after further six months there was a reversal of the changes, and a new Soper lens was fitted with a better pattern and a 20/40 vision. Discussion: This case shows the occurrence of corneal de-formity in a keratoconus patient using RGP lenses. The au-thor discusses the pathophysiology and clinical and topographical diagnosis of corneal warpage, emphasizing the fact that patients with keratoconus as well as normal patients, can have these alterations which should be differentiated from the keratoconus evolution itself.
- ItemAcesso aberto (Open Access)Lente de contato escleral na reabilitação ocular de pacientes com síndrome de Stevens-Johnson(Conselho Brasileiro de Oftalmologia, 2010-10-01) Siqueira, Ana Carolina Punzi de [UNIFESP]; Santos, Myrna Serapião dos [UNIFESP]; Farias, Charles Costa de [UNIFESP]; Barreiro, Telma Regina Maria Pereira [UNIFESP]; Gomes, José Álvaro Pereira [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)PURPOSE: To evaluate the efficacy of scleral contact lenses use on the management of ocular sequelae from Stevens-Johnson syndrome patients. METHODS: In a retrospective study, patients who suffered sequelae of Stevens-Johnson syndrome and started the use of scleral contact lenses were followed. Patients were submitted to an evaluation of symptoms through a questionnaire; ophthalmologic exam (visual acuity measurement, biomicroscopy, ocular surface staining with fluorescein drops, Schirmer test). RESULTS: Ten eyes of seven patients were analyzed. Visual acuity varied from hand movements to 20/25. All patients presented some degree of corneal opacity and slight symblepharon. In patients whose adaptation to scleral contact lenses was successful (90%), they all refered improvement of symptoms and sight. As for the biomicroscopic findings it was observed an improvement of conjunctival hyperemia and keratitis and a reduction of the mucous secretion in 90% the cases. CONCLUSIONS: A successful adaptation to scleral contact lenses was feasible on most patients, with relief of symptoms and better visual acuity, probably due to regularization of the surface. Scleral contact lenses represent an important and accessible alternative to reduce the limitations inferred by the damages from Stevens-Johnson syndrome.
- ItemAcesso aberto (Open Access)Úlcera de córnea bilateral por Pseudomonas em usuário de lente de contato descartável(Conselho Brasileiro de Oftalmologia, 1999-12-01) Lipener, César [UNIFESP]; Ribeiro, André Luiz Parolin [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)Introduction: Although the use of contact lenses is appa-rently very simple, it is necessary to obey criteria for their correct use, conservation and disposal. Corneal bacterial ulcers are a much-feared complication for users of contact lenses and can be related to various factors such as hygiene, storage and most of all long-term use. Purpose: To describe a case of bilateral ulcer, caused by Pseudomonas in a patient who was a user of disposable lenses. This study highlights and discusses the importance of prior examination, instruction and adequate supervision. In addition it is emphasized that although the lenses are disposable, they are not free from the possibility of serious complications. Case Study: A seventeen-year-old student who had used contact lenses for six months without prior examination or medical prescription complained of pain in the left eye. When he was examined, we observed a corneal ulcer infiltrated in the median periphery. Samples were collected and a treatment with fortified eye-drops was started. After eight hours the patient returned now complaining of pain in the right eye which we examined and observed diffuse keratitis with a mucopurulent secretion. The treatment was the same. Laboratory tests revealed Pseudomonas in both eyes and the ailment was healed within a week's treatment without leaving sequelae. Discussion: The author discuss the factors involved in the occurrence of infectious keratitis in users of contact lenses illustrating that even though disposable lenses are appa-rently very simple they can cause serious problems. It also demonstrates that the long-term use of contact lenses is considered to be a main risk factor. The description of a case of bilateral keratitis is a warning about the use of this kind of lens without proper orientation and supervision.
- ItemAcesso aberto (Open Access)Uso da topografia de córnea na adaptação de lente de contato rígida gás-permeável em pacientes portadores de ceratocone: descrição de técnica e resultados preliminares(Conselho Brasileiro de Oftalmologia, 2002-09-01) Gomes, José Álvaro Pereira [UNIFESP]; Lani, Luiz Alexandre; Juliano, Yara; Gomes, Roseli; Pedro, Erik Alessandro; Anbar, Roberto; Universidade Federal de São Paulo (UNIFESP); Clínica de Olhos Dr. Suel Abujamra; Faculdade de Medicina de Santo AmaroPurpose: To introduce a practical method based on the topographic values for rigid gas-permeable contact lens (RGPCL) fitting in keratoconus patients. Methods: Thirty-three eyes of 17 consecutive patients with keratoconus were studied between July 1997 and April 1999. The initial ophthalmologic examination consisted of visual acuity examination, refraction, biomicroscopy, corneal topography with Eye Sys system. The tested contact lenses were selected based on results of corneal topography 1.5 mm superiorly from the visual axis at 90º the base curve. Results: Rigid gas-permeable contact lens fitting was successful in 30 eyes (91%). There was improvement in visual acuity in all eyes, ranging from 20/20 to 20/60. A mean of 3 ±1 tests were performed to select the final contact lenses parameters. Refitting was necessary in 3 cases (10%). The majority of the rigid gas-permeable contact lenses (57%) had their base curves similar to K 1.5 mm superiorly from the visual axis compared to K value. This finding was confirmed with statistical analysis of the individual measurements and the mean differences between the two topographic measurements and the final base curve of the lens. Conclusions: Rigid gas-permeable contact lens fitting based on the corneal topography 1.5 mm superior from the visual axis at 90º showed to be easy and efficient for eyes with keratoconus.