Navegando por Palavras-chave "Aphakia"

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    Biomicroscopia ultra-sônica na avaliação da posição das lentes intra-oculares em uma técnica de fixação escleral
    (Conselho Brasileiro de Oftalmologia, 2000-10-01) Vianna Filho, Raul de Camargo [UNIFESP]; Freitas, Lincoln de [UNIFESP]; Allemann, Norma [UNIFESP]; Hofling-Lima, Ana Luisa [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)
    Purpose: To assess, through ultrasound biomicroscopy (UBM), the positioning of the intraocular lenses (IOL) haptics as related to the ciliary sulcus by using a scleral fixation technique; and to evaluate, as well, if two fixation points are sufficient to avoid tilting of the lenses. Methods: Sixteen aphakic eyes underwent an IOL implan-tation by means of the same scleral fixation technique, performed by the same surgeon. One month following surgery, both the positioning of the IOL haptics and the distances between the IOLs and the cornea were assessed by UBM. Results were statistically studied. Results: Of the 32 intraocular lenses haptics fixed to the sclera, eight were placed in the ciliary sulcus and 24 were placed out of the ciliary sulcus. There was no statistical difference in the distances measured between the intraocular lenses and the cornea for the haptics placed out of the ciliary sulcus as compared to the haptics placed in the ciliary sulcus, suggesting that other factors, besides the distance to the limbus, may be relevant in the positioning of haptics in the ciliary sulcus. The same measurements performed at 3, 6, 9, and 12 hours, on the periphery of the lenses, were also similar, suggesting that 2-point fixation is sufficient to avoid tilting of the lenses in the eye. Conclusions: Further factors (e.g. the ciliary sulcus opening angle), other than the distance of the limbus where the sclera is transfixed, are important for the placement of the lenses in the ciliary sulcus. Two fixation points are sufficient to avoid tilting of the IOL in the eye.
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    Lente de contato em crianças: aspectos epidemiológicos
    (Conselho Brasileiro de Oftalmologia, 2008-06-01) Salame, André Luiz Alves [UNIFESP]; Simon, Eduardo José Maidana [UNIFESP]; Leal, Fernando [UNIFESP]; Lipener, César [UNIFESP]; Brocchetto, Daniela [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)
    PURPOSE: To describe the epidemiology of children submitted to contact lens fit. METHODS: Retrospective study of 73 children that had been submitted to contact lens fit at the Universidade Federal de São Paulo (UNIFESP). This study analyzed sex distribution, age, diagnosis, indications and contact lens fitted at first examination. RESULTS: 34 children (46.6%) were male and 39 (53.4%) female, aged between 2 and 12 years with mean of 10.2 and standard deviation of 2.42. The most common diagnosis was aphakia, in 16 (21.9%) cases. Keratoconus was present in 14 (19.1%), leucoma in 11 (15%), anisometropia in 10 (13.7%), refractive errors in 9 (12.3%), irregular astigmatism in 7 (9.5%), ectopia lentis in 4 (5.4%), high myopia in one case (1.3%) and one child (1.3%) had no ocular pathology, just wishing to change eye color. 52 (71.2%) had medical indication, 9 (12.3%) had optical indication and 12 (16.4%) had cosmetic indication. Contact lenses were fitted in 103 eyes, the most tested lens was rigid gas permeable in 43 (41.7%), soft lens in 41 (39.8%) and cosmetic soft lens in 11 (10.6%). CONCLUSION: Aphakia was the most common diagnosis among children in use of contact lens. The incidence of medical indication was higher than the others and the most tested lens was the rigid gas permeable one.
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    Novo dispositivo para correção da afacia sem suporte capsular: prova de conceito
    (Universidade Federal de São Paulo (UNIFESP), 2020-12-18) Bergamasco, Victor Dias [UNIFESP]; Campos, Mauro Silveira De Queiroz [UNIFESP]; Universidade Federal de São Paulo
    Introduction: According to the World Health Organization (WHO), cataract is a leading cause of visual impairment (best corrected visual acuity under 20/60) worldwide. Facectomy is one of the most performed surgeries in modern society. More than 30 million patients will go through cataract extraction in 2020. Even though it is a safe and predictable procedure still some complications may occur, for example the loss of capsular support resulting in impossibility to perform intraocular lens implant and aphakia. In those cases, other ocular tissues are used to support the lens in the absence of capsular bag support and many techniques have been described in the literature. The present techniques have several unmet needs; are technically difficult for most surgeons, require special lens and surgical instruments, multiple incisions and sutures, lead to intense inflammatory response and to short and long-term intraocular pressure disorders and IOL displacement and tilt. The ideal solution should be technically easy and accessible with no need of special lens or surgical instruments, minimally invasive and predictable and stable IOL positioning. Purposes: To develop a prototype device for aphakia without capsular bag support resolution. To describe the development methodology. To evaluate the prototyping technologies used. To evaluate the prototype clinical effectiveness through a proof of concept. Methods: For this technology development project a development cycle was created and applied. The cycle consisted in idealization, prototyping, evaluation and improvements proposition. Using this development cycle nine prototype versions were created and evaluated for the most relevant aspects for the concept. The evaluation consisted in grading each relevant aspect of each prototype version. To determine the best prototype the scores for each aspect of each version were added and resulted in a final score per prototype. The highest prototype score was considered the best prototype. Results: Nine prototypes were idealized and created. Versions V1P to V7P were developed for cadaveric porcine eyes testing. Versions V8H and V9H were tested in human cadaveric eyes. A simplified implant technic was developed and the version V9H had the highest score and was considered the most satisfactory for the evaluated aspects. Conclusions: It was possible to develop a prototype device for aphakia without capsular bag support resolution as well as to describe the development methodology. It was possible to successfully evaluate the prototyping technologies used and identify that the 3D printing technology was the best option available Although most of the aspects were successfully addressed in the best evaluated version, IOL positioning and stability remains unsatisfactory.