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1.
Am J Ophthalmol Case Rep ; 17: 100575, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31909292

RESUMO

PURPOSE: To present the case of a 6-year-old child who presented with a traumatic cataract and was treated with trifocal toric intra-ocular lens implantation. OBSERVATIONS: The child's uncorrected distance visual acuity improved from +0.7 logMAR preoperatively to 0.00 logMAR after cataract surgery, with spectacle independence and no reported side effects. CONCLUSIONS AND IMPORTANCE: In carefully selected pediatric patients with traumatic cataracts, trifocal toric intra-ocular lenses may offer some benefit over standard monofocal lenses.

2.
J Environ Radioact ; 160: 25-7, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27116402

RESUMO

It is proposed a method for the determination of (226)Ra in offshore platform liquid effluent samples (produced water). The method is based on a two-phase liquid scintillation counting system and allows for the direct and simple determination of (226)Ra content. Samples with high barium content may also have high (226)Ra concentration. Therefore, the sample volume is based on the barium concentration and ranges from 10 mL to 100 mL. Our new method was tested using multiple real samples and was compared with the BaSO4 precipitation method. The results based on the LSC were 30% higher than the precipitation method, which is attributed to the self-absorption of alpha particles in the BaSO4 precipitate. The determination of both (226)Ra and (228)Ra in the liquid effluent of offshore oil platforms is mandatory in Brazil. Thus, a second method of accurately assessing (228)Ra content remains necessary.


Assuntos
Campos de Petróleo e Gás , Rádio (Elemento)/análise , Poluentes Radioativos da Água/análise , Bário/análise , Sulfato de Bário/química , Brasil , Precipitação Química , Rádio (Elemento)/química , Contagem de Cintilação , Poluentes Radioativos da Água/química
3.
Arq. bras. oftalmol ; 78(5): 305-309, Sep.-Oct. 2015. tab, ilus
Artigo em Inglês | LILACS | ID: lil-761515

RESUMO

ABSTRACTPurpose:To investigate the relationship between quantitative iris parameters and the presence of keratoconus.Methods:Cross-sectional observational study that included 15 affected eyes of 15 patients with keratoconus and 26 eyes of 26 normal age- and sex-matched controls. Iris parameters (area, thickness, and pupil diameter) of affected and unaffected eyes were measured under standardized light and dark conditions using anterior segment optical coherence tomography (AS-OCT). To identify optimal iris thickness cutoff points to maximize the sensitivity and specificity when discriminating keratoconus eyes from normal eyes, the analysis included the use of receiver operating characteristic (ROC) curves.Results:Iris thickness and area were lower in keratoconus eyes than in normal eyes. The mean thickness at the pupillary margin under both light and dark conditions was found to be the best parameter for discriminating normal patients from keratoconus patients. Diagnostic performance was assessed by the area under the ROC curve (AROC), which had a value of 0.8256 with 80.0% sensitivity and 84.6% specificity, using a cutoff of 0.4125 mm. The sensitivity increased to 86.7% when a cutoff of 0.4700 mm was used.Conclusions:In our sample, iris thickness was lower in keratoconus eyes than in normal eyes. These results suggest that tomographic parameters may provide novel adjunct approaches for keratoconus screening.


RESUMOObjetivo:Investigar a relação entre os parâmetros quantitativos irianos e a presença de ceratocone.Métodos:Estudo observacional transversal com quinze olhos de 15 pacientes com ceratocone e 26 olhos de 26 indivíduos normais, pareados por idade e gênero. Parâmetros da íris (área, espessura e diâmetro da pupila) de olhos com ceratocone e olhos sem ceratocone foram medidos usando tomografia de coerência óptica do segmento anterior (AS-OCT), em condições padronizadas de alta luminosidade e ambiente escuro. Com o objetivo de maximizar a sensibilidade, especificidade e identificar o melhor ponto de corte na diferenciação entre ceratocone e indivíduos normais, foi realizada a análise quantitativa da curva característica operacional do receptor (ROC) dos parâmetros de espessura da íris.Resultados:A área e espessura da íris estavam reduzidas nos olhos de pacientes com ceratocone. Observamos que o melhor parâmetro para discriminar indivíduos normais de pacientes com ceratocone foi a espessura média na margem pupilar, tanto em condições de alta luminosidade quanto em ambiente escuro. O desempenho diagnóstico deste parâmetro foi avaliado pela análise quantitativa da área sob a curva ROC (AROC), mostrando AROC de 0,8256, com sensibilidade de 80,0% e especificidade de 84,6% usando um ponto de corte de 0,4125 milímetros de espessura da íris. A sensibilidade aumentou para 86,7%, com um corte de 0,4700 milímetros de espessura da íris.Conclusões:Na amostra deste estudo, a espessura da íris demostrou-se reduzida nos olhos com ceratocone. Estes resultados sugerem que os parâmetros tomográficos podem proporcionar novas informações no auxilio da triagem de pacientes com ceratocone.


Assuntos
Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Iris/patologia , Ceratocone/patologia , Tomografia de Coerência Óptica , Córnea/patologia , Escuridão , Métodos Epidemiológicos , Iris/fisiopatologia , Ceratocone/fisiopatologia , Raio , Valores de Referência , Acuidade Visual
4.
Am J Ophthalmol ; 159(5): 829-34.e2, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25640409

RESUMO

PURPOSE: To assess the results of a single eye bank preparing a high volume of Descemet membrane endothelial keratoplasty (DMEK) tissues using multiple technicians to provide an overview of the experience and to identify possible risk factors for DMEK preparation failure. DESIGN: Cross-sectional study. METHODS: setting: Lions VisionGift and Wilmer Eye Institute at Johns Hopkins Hospital. STUDY POPULATION: All 563 corneal tissues processed by technicians at Lions VisionGift for DMEK between October 2011 and May 2014 inclusive. OBSERVATION PROCEDURES: Tissues were divided into 2 groups: DMEK preparation success and DMEK preparation failure. MAIN OUTCOME MEASURES: We compared donor characteristics, including past medical history. RESULTS: The overall tissue preparation failure rate was 5.2%. Univariate analysis showed diabetes mellitus (P = .000028) and its duration (P = .023), hypertension (P = .021), and hyperlipidemia or obesity (P = .0004) were more common in the failure group. Multivariate analysis showed diabetes mellitus (P = .0001) and hyperlipidemia or obesity (P = .0142) were more common in the failure group. Elimination of tissues from donors either with diabetes or with hyperlipidemia or obesity reduced the failure rate from 5.2% to 2.2%. Trends toward lower failure rates occurring with increased technician experience also were found. CONCLUSIONS: Our work showed that tissues from donors with diabetes mellitus (especially with longer disease duration) and hyperlipidemia or obesity were associated with higher failure rates in DMEK preparation. Elimination of tissues from donors either with diabetes mellitus or with hyperlipidemia or obesity reduced the failure rate. In addition, our data may provide useful initial guidelines and benchmark values for eye banks seeking to establish and maintain DMEK programs.


Assuntos
Doenças da Córnea/cirurgia , Lâmina Limitante Posterior/patologia , Ceratoplastia Endotelial com Remoção da Lâmina Limitante Posterior , Endotélio Corneano/patologia , Bancos de Olhos/estatística & dados numéricos , Manejo de Espécimes/estatística & dados numéricos , Adulto , Idoso , Consumo de Bebidas Alcoólicas/efeitos adversos , Contagem de Células , Estudos Transversais , Bases de Dados Factuais , Ceratoplastia Endotelial com Remoção da Lâmina Limitante Posterior/estatística & dados numéricos , Complicações do Diabetes , Seleção do Doador , Humanos , Hiperlipidemias/complicações , Hipertensão/complicações , Pessoa de Meia-Idade , Obesidade/complicações , Estudos Retrospectivos , Fatores de Risco , Fumar/efeitos adversos , Manejo de Espécimes/normas , Doadores de Tecidos , Falha de Tratamento
5.
Cornea ; 33(8): 865-7, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24915019

RESUMO

PURPOSE: The aim of this study was to relate a case of deep anterior lamellar keratoplasty (DALK) converted to penetrating keratoplasty in which the host central Descemet membrane (DM) with a large perforation was left attached to the host cornea. METHODS: This is a case report of a 34-year-old man who underwent an attempted DALK for keratoconus in his left eye, which became complicated with a large rupture in DM during dissection. The host DM was left in place, the donor cornea with DM intact was sutured onto the host bed, and air was injected into the anterior chamber. The patient was monitored by biomicroscopy, pachymetry, topography, anterior segment optical coherence tomography, and specular microscopy. RESULTS: The postoperative course resulted in improved uncorrected visual acuity, best spectacle-corrected visual acuity, and topography. Corneal edema was observed in the host cornea peripheral to the graft. Three months after the surgery, the endothelial cell density was reduced by 63% compared with the preoperative donor cell density. CONCLUSIONS: Leaving the host DM during conversion of DALK to penetrating keratoplasty was uneventful in this case, although corneal edema was observed in the area overlying the host cornea. It is possible that the retained DM could provide additional autologous endothelial cells to prolong graft survival.


Assuntos
Transplante de Córnea/métodos , Lâmina Limitante Posterior/patologia , Ceratocone/cirurgia , Ceratoplastia Penetrante/métodos , Adulto , Paquimetria Corneana , Perfuração da Córnea/patologia , Topografia da Córnea , Humanos , Masculino , Doadores de Tecidos , Tomografia de Coerência Óptica , Acuidade Visual/fisiologia
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