Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 8 de 8
Filtrar
1.
Ophthalmol Sci ; 4(4): 100481, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38694494

RESUMO

Purpose: To evaluate the performance of artificial intelligence (AI) systems embedded in a mobile, handheld retinal camera, with a single retinal image protocol, in detecting both diabetic retinopathy (DR) and more-than-mild diabetic retinopathy (mtmDR). Design: Multicenter cross-sectional diagnostic study, conducted at 3 diabetes care and eye care facilities. Participants: A total of 327 individuals with diabetes mellitus (type 1 or type 2) underwent a retinal imaging protocol enabling expert reading and automated analysis. Methods: Participants underwent fundus photographs using a portable retinal camera (Phelcom Eyer). The captured images were automatically analyzed by deep learning algorithms retinal alteration score (RAS) and diabetic retinopathy alteration score (DRAS), consisting of convolutional neural networks trained on EyePACS data sets and fine-tuned using data sets of portable device fundus images. The ground truth was the classification of DR corresponding to adjudicated expert reading, performed by 3 certified ophthalmologists. Main Outcome Measures: Primary outcome measures included the sensitivity and specificity of the AI system in detecting DR and/or mtmDR using a single-field, macula-centered fundus photograph for each eye, compared with a rigorous clinical reference standard comprising the reading center grading of 2-field imaging protocol using the International Classification of Diabetic Retinopathy severity scale. Results: Of 327 analyzed patients (mean age, 57.0 ± 16.8 years; mean diabetes duration, 16.3 ± 9.7 years), 307 completed the study protocol. Sensitivity and specificity of the AI system were high in detecting any DR with DRAS (sensitivity, 90.48% [95% confidence interval (CI), 84.99%-94.46%]; specificity, 90.65% [95% CI, 84.54%-94.93%]) and mtmDR with the combination of RAS and DRAS (sensitivity, 90.23% [95% CI, 83.87%-94.69%]; specificity, 85.06% [95% CI, 78.88%-90.00%]). The area under the receiver operating characteristic curve was 0.95 for any DR and 0.89 for mtmDR. Conclusions: This study showed a high accuracy for the detection of DR in different levels of severity with a single retinal photo per eye in an all-in-one solution, composed of a portable retinal camera powered by AI. Such a strategy holds great potential for increasing coverage rates of screening programs, contributing to prevention of avoidable blindness. Financial Disclosures: F.K.M. is a medical consultant for Phelcom Technologies. J.A.S. is Chief Executive Officer and proprietary of Phelcom Technologies. D.L. is Chief Technology Officer and proprietary of Phelcom Technologies. P.V.P. is an employee at Phelcom Technologies.

2.
Ophthalmic Surg Lasers Imaging Retina ; 54(3): 174-182, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36944070

RESUMO

BACKGROUND AND OBJECTIVE: The goal of this study was to assess macular vascular density evolution, macular thickness, and functional outcomes after intravitreal dexamethasone implants for diabetic macular edema. PATIENTS AND METHODS: Vascular density was evaluated with optical coherence tomography (OCT) angiography in 21 eyes. Macular thickness was evaluated with structural OCT. Visual acuity and contrast sensitivity were evaluated before and after treatment, and these functional outcomes were analyzed for association with anatomic outcomes. Macular vessel density in the superficial capillary plexus was evaluated with OCT angiography and quantified in areas with no fluid, allowing a more accurate measurement and eliminating the segmentation bias in areas with intra-retinal fluid. Such a methodology was possible by positioning the scans only in areas with no fluid before and after the implant. The absence of fluid in these areas was confirmed by three experienced evaluators using both the B-scan and the en face. Visual acuity and contrast sensitivity were evaluated before and after treatment, and these functional outcomes were analyzed for association with anatomic outcomes. RESULTS: At 30, 60, and 90 days after implantation, there was improvement in macular perfusion in areas without fluid after intravitreal dexamethasone implantation, accompanied by reduced macular thickness and improved visual acuity (P < .001). However, there was no improvement in contrast sensitivity after treatment. CONCLUSIONS: Improved macular perfusion after treatment with intravitreal dexamethasone implantation may be associated with modulation of leukostasis, when the release of cytokines leads to capillary endothelial damage and obstruction of the micro-vasculature, leading to impaired capillary perfusion and ischemic damage. Despite the anatomical and functional findings demonstrated, further studies are needed to prove the relationship between the inflammatory mechanisms of diabetic macular edema and its relationship with macular perfusion and functional aspects. [Ophthalmic Surg Lasers Imaging Retina 2023;54(3):174-182.].


Assuntos
Diabetes Mellitus , Retinopatia Diabética , Edema Macular , Humanos , Angiografia , Dexametasona , Retinopatia Diabética/complicações , Retinopatia Diabética/diagnóstico , Retinopatia Diabética/tratamento farmacológico , Implantes de Medicamento , Glucocorticoides/uso terapêutico , Injeções Intravítreas , Edema Macular/diagnóstico , Edema Macular/tratamento farmacológico , Edema Macular/etiologia , Estudos Prospectivos , Tomografia de Coerência Óptica/métodos
4.
Int J Retina Vitreous ; 7(1): 4, 2021 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-33422155

RESUMO

BACKGROUND: Diabetic macular edema (DME) is a major cause of visual impairment and its treatment is a public health challenge. Even though anti-angiogenic drugs are the gold-standard treatment, they are not ideal and subthreshold laser (SL) remains a viable and promising therapy in selected cases. The aim of this study was to evaluate its efficacy in a real-life setting. METHODS: Retrospective case series of 56 eyes of 36 patients with center-involving DME treated with SL monotherapy. Treatment was performed in a single session with the EasyRet® photocoagulator with the following parameters: 5% duty cycle, 200-ms pulse duration, 160-µm spot size and 50% power of the barely visible threshold. A high-density pattern was then applied to the whole edematous area, using multispot mode. Best corrected visual acuity (BCVA) and optical coherence tomography (OCT) data were obtained at baseline and around 3 months after treatment. RESULTS: Fifty-six eyes of 36 patients were included (39% women, mean age 64.8 years old); mean time between treatment day and follow-up visit was 14 ± 6 weeks. BCVA (Snellen converted to logMAR) was 0.59 ± 0.32 and 0.43 ± 0.25 at baseline and follow-up, respectively (p = 0.002). Thirty-two percent had prior panretinal photocoagulation (p = 0.011). Mean laser power was 555 ± 150 mW and number of spots was 1,109 ± 580. Intraretinal and subretinal fluid (SRF) was seen in 96 and 41% of eyes at baseline and improved in 35 and 74% of those after treatment, respectively. Quantitative analysis of central macular thickness (CMT) change was performed in a subset of 23 eyes, 43% of which exhibited > 10% CMT reduction post-treatment. CONCLUSIONS: Subthreshold laser therapy is known to have RPE function as its main target, modulating the activation of heat-shock proteins and normalizing cytokine expression. In the present study, the DME cases associated with SRF had the best anatomical response, while intraretinal edema responded poorly to laser monotherapy. BCVA and macular thickness exhibited a mild response, suggesting the need for combined treatment in most patients. Given the effect on SRF reabsorption, subthreshold laser therapy could be a viable treatment option in selected cases.

5.
PeerJ ; 7: e7850, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31687270

RESUMO

BACKGROUND: The problem of access to medical information, particularly in low-income countries, has been under discussion for many years. Although a number of developments have occurred in the last decade (e.g., the open access (OA) movement and the website Sci-Hub), everyone agrees that these difficulties still persist very widely, mainly due to the fact that paywalls still limit access to approximately 75% of scholarly documents. In this study, we compare the accessibility of recent full text articles in the field of ophthalmology in 27 established institutions located worldwide. METHODS: A total of 200 references from articles were retrieved using the PubMed database. Each article was individually checked for OA. Full texts of non-OA (i.e., "paywalled articles") were examined to determine whether they were available using institutional and Hinari access in each institution studied, using "alternative ways" (i.e., PubMed Central, ResearchGate, Google Scholar, and Online Reprint Request), and using the website Sci-Hub. RESULTS: The number of full texts of "paywalled articles" available using institutional and Hinari access showed strong heterogeneity, scattered between 0% full texts to 94.8% (mean = 46.8%; SD = 31.5; median = 51.3%). We found that complementary use of "alternative ways" and Sci-Hub leads to 95.5% of full text "paywalled articles," and also divides by 14 the average extra costs needed to obtain all full texts on publishers' websites using pay-per-view. CONCLUSIONS: The scant number of available full text "paywalled articles" in most institutions studied encourages researchers in the field of ophthalmology to use Sci-Hub to search for scientific information. The scientific community and decision-makers must unite and strengthen their efforts to find solutions to improve access to scientific literature worldwide and avoid an implosion of the scientific publishing model. This study is not an endorsement for using Sci-Hub. The authors, their institutions, and publishers accept no responsibility on behalf of readers.

6.
Undersea Hyperb Med ; 42(2): 125-31, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26094287

RESUMO

INTRODUCTION: Choroidal neovascularization (CNV) is one of the leading causes of blindness worldwide and affects patients with wet age-related macular degeneration (AMD). Its natural course may lead to impaired central vision and macular fibrosis. Even VEGF blockade, currently the best available treatments for CNV, may fail to improve vision. Hyperbaric oxygen (HBO2) therapy may be an alternative or ancillary treatment for CNV. METHODS: AMD patients with active CNV underwent 10 daily sessions of HBO2 at 2 atmospheres absolute (atm abs) for 120 minutes each session. After the end of the sessions, patients with clinical or tomographical signs of CNV activity underwent standard anti-VEGF treatment. RESULTS: Seven patients (average age 73) underwent 10 daily 120-minute sessions of HBO2 at 2 atm abs. After the sessions, five patients underwent intravitreal injection of bevacizumab. Average follow-up was 150 days. Average CNV area at baseline was 14.42 mm2; average CNV greatest linear diameter at baseline was 4.56 mm. Statistical analysis of variance (ANOVA) was performed for central retinal thickness and volume mean percentage changes post-treatment. At the end of follow up, five patients showed anatomical improvement, one patient maintained anatomical aspect and one patient showed anatomical worsening. CONCLUSION: HBO2 may be a safe and tolerable treatment option for patients with active CNV, potentially delaying its progression, as monotherapy or in combination with intravitreal bevacizumab.


Assuntos
Inibidores da Angiogênese/administração & dosagem , Anticorpos Monoclonais Humanizados/administração & dosagem , Neovascularização de Coroide/terapia , Oxigenoterapia Hiperbárica/métodos , Degeneração Macular/complicações , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Bevacizumab , Neovascularização de Coroide/etiologia , Terapia Combinada/métodos , Feminino , Humanos , Oxigenoterapia Hiperbárica/efeitos adversos , Injeções Intravítreas , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Acuidade Visual
7.
Rev. bras. ter. comport. cogn ; 2(2): 147-155, jul.-dez. 2000. tab
Artigo em Português | LILACS | ID: lil-444652

RESUMO

A aderência é um fator importante tanto por influenciar resultados de pesquisas, como para a prática clínica. Durante um estudo sobre Fobia Social, detectou-se uma pobre aderência entre pacientes submetidos a psicoterapia em grupo, tendo os pacientes abandonado a terapia em etapas diferentes. Essa diferença sugeriu a possibilidade de tratar-se de grupos de pacientes com características diferentes entre si, que pudessem motivar esse abandono em etapas diferentes. Pacientes que abandonaram o tratamento antes de sua conclusão foram convocados para uma entrevista que visava à identificação de fatores que poderiam predizer a baixa aderência. Os dados colhidos pelas entrevistas foram categorizados e apontaram fatores comuns: pacientes com antecedentes de baixa aderência, percepção distorcida dos resultados do tratamento e de seu status clínico, falta de motivação para o tratamento e a atribuição dos sintomas à personalidade ao invés de encará-los como uma doença. A partir destas constatações, recomendam-se intervenções terapêuticas no sentido de melhorar a aderência como educar o paciente sobre aspectos de sua doença e do tratamento, fornecer ao paciente indícios objetivos de sua melhora, garantir a motivação dos pacientes e avaliar a aderência ao longo do tratamento de modo a detectar pacientes que poderão abandonar o tratamento


Assuntos
Humanos , Masculino , Adulto , Pacientes Desistentes do Tratamento/psicologia , Psicoterapia de Grupo , Transtornos Fóbicos/psicologia
8.
Rev. bras. ter. comport. cogn ; 2(2): 147-155, jul.-dez. 2000. tab
Artigo em Português | Index Psicologia - Periódicos | ID: psi-17455

RESUMO

A aderência é um fator importante tanto por influenciar resultados de pesquisas, como para a prática clínica. Durante um estudo sobre Fobia Social, detectou-se uma pobre aderência entre pacientes submetidos a psicoterapia em grupo, tendo os pacientes abandonado a terapia em etapas diferentes. Essa diferença sugeriu a possibilidade de tratar-se de grupos de pacientes com características diferentes entre si, que pudessem motivar esse abandono em etapas diferentes. Pacientes que abandonaram o tratamento antes de sua conclusão foram convocados para uma entrevista que visava à identificação de fatores que poderiam predizer a baixa aderência. Os dados colhidos pelas entrevistas foram categorizados e apontaram fatores comuns: pacientes com antecedentes de baixa aderência, percepção distorcida dos resultados do tratamento e de seu status clínico, falta de motivação para o tratamento e a atribuição dos sintomas à personalidade ao invés de encará-los como uma doença. A partir destas constatações, recomendam-se intervenções terapêuticas no sentido de melhorar a aderência como educar o paciente sobre aspectos de sua doença e do tratamento, fornecer ao paciente indícios objetivos de sua melhora, garantir a motivação dos pacientes e avaliar a aderência ao longo do tratamento de modo a detectar pacientes que poderão abandonar o tratamento (AU)


Assuntos
Humanos , Masculino , Adulto , Transtornos Fóbicos/psicologia , Psicoterapia de Grupo , Pacientes Desistentes do Tratamento/psicologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA