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One of the initial steps in the preprocessing of digital fundoscopy images is the identification of pixels containing relevant information. This can be achieved through different approaches, one of them is implementing background extraction, reducing the set of pixels to be analyzed later in the process. In this work, we present a background extraction method for digital fundoscopy images based on computational topology. By interpreting binarized images as cubical complexes and extracting their homological groups in 1 and 2 dimensions we identify a subset of luminescence values that can be used to binarize the original grayscale image, obtaining a mask to achieve background extraction. This method is robust to noise and suboptimal image quality, facilitating the analytical pipeline in the context of computer aided diagnosis approaches. This method facilitates the segmentation of the background of a digital fundoscopy image, which allows further methods to focus on pixels with relevant information (eye fundus). This tool is best suited to be implemented in the preprocessing stages of the analytical pipeline by computational ophthalmology specialists.•It is robust to noise and low-quality images.•Output provides an ideal scenario for down-the-line analysis by facilitating only relevant pixels in a digital fundoscopy.

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This review will provide a better understanding of a set of signs known as malarial retinopathy. The discovery of this retinopathy in association with cerebral malaria is important because it best distinguishes patients with true cerebral malaria from those with coma due to other causes and incidental Plasmodium falciparum parasitemia. Identifying a comatose patient with malarial retinopathy increases the likelihood of an accurate severe or cerebral malaria diagnosis. As the World Health Organization does not specify that malarial retinopathy is one of the factors included in determining a cerebral malaria diagnosis, there are significant false-positive diagnoses of cerebral malaria. Once a cerebral malaria diagnosis is assigned, other possibilities and treatments are often excluded making an incorrect diagnosis of cerebral malaria potentially fatal. However, Plasmodium falciparum may also contribute to coma in some children with retinopathy-negative cerebral malaria, as this group is still not clinically well characterized, so all children with the WHO definition of cerebral malaria should be treated for severe malaria. Nevertheless, by raising awareness about malarial retinopathy, there could be a greater potential to accurately diagnose cerebral malaria and thus achieve more positive patient outcomes in the future. This literary review aims to raise awareness of the retinopathy by defining what it is to non-experts, explaining its pathology, clarifying the techniques needed to accurately diagnose malarial retinopathy, as well as the barriers that prevent clinicians from providing a proper diagnosis in malaria-endemic regions; and finally, discuss future directions to continue the study of malarial retinopathy.

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The evaluation of central vestibular syndromes, especially in the acute setting, can pose a challenge even for the most experienced clinician. Of particular importance is the evaluation of ocular torsion and nystagmus, which can be sensitive for central vestibular pathology, but easily missed by the untrained eye. We present two cases of acute vestibular syndrome of central origin in which the use of magnified fundoscopy at the bedside aided the precise anatomical diagnosis to inform appropriate further management. We also review aspects of the pathophysiology and anatomy of vestibular roll plane disorders. In case 1, the finding of position-dependent ocular torsion facilitated a rapid distinction between central skew deviation and a trochlear nerve palsy. In case 2, the fundoscopic magnification identified a pure rotatory nystagmus indicative of a central vestibular disorder. Ophthalmoscopy remains a useful bedside technique in acute vertigo, but the use of inexpensive magnification with a smartphone can provide objective and recordable evidence of central vestibular pathology, aiding therapeutic decisions.

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OBJECTIVE: To describe ophthalmic examination and diagnostic values for Schirmer tear test (STT), intraocular pressure (IOP), corneal horizontal diameter (CHD), palpebral fissure length (PFL), fundoscopy, and palpebral conjunctiva microbiota from healthy giant anteaters. ANIMALS STUDIED: Twelve giant anteaters (Myrmecophaga tridactyla), 11 adults and one juvenile, five males and seven females. PROCEDURES: The animals were submitted to general anesthesia and ophthalmic evaluation with portable slit-lamp biomicroscope, Finoff transilluminator, and fundoscopy, as well as STT, bacterial culture from palpebral conjunctiva, rebound tonometry IOP, and measurement of PFL and CHD. Data compiled were analyzed with ANOVA and Tukey tests. RESULTS: The results (mean ± standard deviation) were as follows: STT 8.04 ± 6.21 mm/min; IOP 10.92 ± 2.45 mmHg; PFL 0.75 ± 0.11 cm; CHD 0.96 ± 0.10 cm. Out of the 24 eyes swab samples for bacterial culture, 17 were positive, with three genera of Gram-positive bacteria identified Staphylococcus spp., Bacillus sp., and Corynebacterium sp. Gram-negative bacteria were not isolated from any of the samples. CONCLUSIONS: As conservation work in this vulnerable species continues, this report on basic ophthalmic examination and diagnostic parameters will be helpful improve their treatment and care. More ophthalmic studies are encouraged in animals within the Pilosa order.

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OBJECTIVE: To describe selected ophthalmic tests and anatomical features of eyes of crab-eating foxes (Cerdocyon thous) and maned wolves (Chrysocyon brachyurus). ANIMALS STUDIED: Six crab-eating foxes (12 eyes), eight maned wolves (16 eyes). PROCEDURES: Intramuscular and/or inhalatory anesthesia, ophthalmic evaluation with portable slit-lamp biomicroscope, Schirmer tear test (STT), intraocular pressure measurement with rebound and applanation (crab-eating fox only) tonometers, measurement of palpebral fissure length (PFL), gonioscopy, and fundoscopy. Data were analyzed with ANOVA and Tukey's tests. RESULTS: Both species presented upper and lower eyelids, both with eyelashes and Meibomian glands openings. A third eyelid was also present. In partial miosis, pigmented projections were observed along the edge of the pupil. The draining angle was open, with thin pectinate ligaments. The retina was holangiotic. For crab-eating foxes, mean ± standard deviation values were as follows: STT: 4.33 ± 2.96 mm/min; PFL: 17.45 ± 1.55 mm; rebound tonometry: 10.70 ± 3.43 mm Hg (TonoVet® calibration D),5.66 ± 3.44 mm Hg (TonoVet® calibration P), 17.00 ± 4.64 mm Hg (TonoVet® Plus calibration dog); and applanation tonometry: 11.70 ± 5.70 mm Hg(TonoPen® XL). For maned wolves, the mean ± standard deviation values were as follows: STT: 9.31 ± 7.40 mm/min; PFL: 22.79 ± 1.63 mm; rebound tonometry: 11.00 ± 2.77 mm Hg (TonoVet® calibration D), 6.78 ± 2.58 mm Hg (TonoVet® calibration P), and 18.29 ± 3.47 mm Hg(TonoVet® Plus calibration dog). CONCLUSIONS: This study contributes with knowledge that can help the clinical assessment regarding eyes of crab-eating foxes and maned wolves. The data herein presented for rebound tonometry are new for both species.

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Resumo Objetivo: Analisar a prevalência de alterações na fundoscopia de pacientes portadores de Diabetes Mellitus (DM) e/ou Hipertensão Arterial Sistêmica (HAS) encaminhados ao Serviço de Referência de Oftalmologia, localizado em uma Unidade Básica de Saúde do município de Patos, Paraíba (PB). Metodos: Estudo de caráter descritivo, transversal e com abordagem quantitativa, que envolveu um total de 22 pacientes. Para a coleta de dados, foi utilizado um questionário sobre a saúde ocular. Além disso, os integrantes da pesquisa participaram do teste da acuidade visual de Snellen e acuidade visual para perto, da medida da pressão intra-ocular e do exame da oftalmoscopia direta. Os que obtiveram pior acuidade visual foram conduzidos para a realização de retinografia. Os dados foram avaliados através de análises estatísticas utilizando o Statistical Package for the Social Sciences - SPSS. Resultados: Do total de 22 pacientes, 11 foram submetidos ao exame de retinografia. Destes, 36,3 % eram apenas diabéticos; 27,4% eram apenas hipertensos e 36,3% eram diabéticos e hipertensos. As principais alterações encontradas foram retinopatia diabética, retinopatia hipertensiva, catarata, glaucoma, nevus de coroide, retinose pigmentar e estafiloma peripapilar. Conclusão: Percebe-se que DM e HAS tem grande impacto negativo sobre a saúde ocular. Para diminuir esse efeito nocivo é necessário que o exame de fundo de olho seja realizado anualmente com a finalidade de diagnosticar precocemente certas patologias e evitar complicações futuras, culminando em menores custos para o sistema de saúde e mais qualidade de vida para os pacientes.

Abstract Objective: To analyze the prevalence of alterations in funduscopy of patients with Diabetes Mellitus (DM) and/or Systemic Arterial Hypertension (SAH) referred to the Ophthalmology Reference Service, located in a Basic Health Unit of the city of Patos, Paraíba). Methods: A descriptive, cross-sectional study with a quantitative approach, which involving a total of 22 patients. For data collection, a questionnaire on ocular health was used. In addition, the research members participated in the Snellen visual acuity test and visual acuity near, intraocular pressure measurement and direct ophthalmoscopy examination. Those who obtained worse visual acuity were conducted for retinography. The data were evaluated through statistical analysis using the Statistical Package for the Social Sciences - SPSS. Results: Of the total of 22 patients, 11 were submitted to retinography. Of these, 36.3% were diabetics only; 27.4% were hypertensive only and 36.3% were diabetic and hypertensive. The main alterations found were diabetic retinopathy, hypertensive retinopathy, cataract, glaucoma, choroidal nevus, pigmentary retinitis and peripapillary staphyloma. Conclusion: It is noticed that DM and SAH have a great negative impact on ocular health. To reduce this harmful effect it is necessary that the fundus eye exam be performed annually for the purpose of early diagnosis of certain pathologies and avoid future complications, culminating in lower costs for the health system and more quality of life for patients.

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INTRODUÇÃO: Descrever os achados fundoscópicos em pacientes com AIDS e neurotoxoplasmose em fase ativa. MÉTODOS: Foi desenvolvido estudo prospectivo tipo série de casos incluindo 70 pacientes, de ambos os sexos, com idade variando de 20 a 63 anos, internados nas enfermarias de três hospitais públicos da Cidade do Recife, Pernambuco, com diagnósticos de AIDS e neurotoxoplasmose firmados segundo os critérios do Centers for Disease Control and Prevention (1992), no período de janeiro a outubro de 2008. Os pacientes se caracterizavam por: primeiro episódio de neurotoxoplasmose (65; 92,9 por cento) ou recidiva (5; 7,1 por cento); desconhecimento de ter AIDS (23; 32,9 por cento), contagem média de linfócitos T CD4 de 139,8 ± 3,04 células/mm3 e carga viral média igual a 137.080 ± 39.380 cópias/mL. Todos foram submetidos a exame oftalmológico, consistindo de: inspeção ocular; aferição da acuidade visual; investigação da função muscular extrínseca ocular e fundoscopia, empregando oftalmoscópio indireto binocular (modelo OHN 3.5 (Eyetec®) e lente externa de 20 dioptrias (Volk®). RESULTADOS: Os achados consistiram em: exsudatos algodonosos retinianos (8,6 por cento), constricção arteriolar difusa leve (8,6 por cento); lesões de retinocoroidite cicatricial, características de toxoplasmose ocular (5,7 por cento), atrofia do epitélio pigmentar retiniano (2,9 por cento), descolamento da retina (2,9 por cento), aumento de escavação papilar (1,4 por cento), degeneração periférica retiniana (1,4 por cento), macroaneurisma (1,4 por cento), papiledema bilateral (1,4 por cento), tração vítreo-retiniana (1,4 por cento). CONCLUSÕES: Pacientes com AIDS e neurotoxoplasmose podem apresentar alterações fundoscópicas características da toxoplasmose ocular, na forma ativa ou cicatricial, relacionadas ao HIV ou, ainda, a outras doenças oportunistas ou sistêmicas, podendo ser de grande auxílio num tratamento integral do paciente por uma equipe multiprofissional.

INTRODUCTION: To describe fundoscopic findings among patients with AIDS and active-phase neurotoxoplasmosis. METHODS: A prospective study of case series type was developed, including 70 patients of both sexes and ages ranging from 20 to 63 years who were admitted to the wards of three public hospitals in the city of Recife, Pernambuco, Brazil, from January to October 2008, with diagnoses of AIDS and neurotoxoplasmosis determined according to the criteria of the Centers for Disease Control and Prevention (1992). The patients were characterized by a first episode of neurotoxoplasmosis (65; 92.9 percent) or recurrence (5; 7.1 percent), unawareness of having AIDS (23; 32.9 percent), mean T CD4+ count of 139.8 ± 3.04 lymphocytes/mm³ and mean viral load of 137,080 ± 39,380 copies/ml. All patients underwent ophthalmological examination consisting of ocular inspection, gauging of visual acuity, investigation of ocular extrinsic muscle function and fundoscopy using a binocular indirect ophthalmoscope (model OHM 3.5 Eyetec®) and external lens of 20 diopters (Volk®). RESULTS: The findings consisted of retinal cotton-wool spot exudates (8.6 percent), slight diffuse arteriolar constriction (8.6 percent), retinochoroiditis scars characteristic of ocular toxoplasmosis (5.7 percent), atrophy of retinal pigment epithelium (2.9 percent), retinal detachment (2.9 percent), increased papillary excavation (1.4 percent), retinal peripheral degeneration (1,4 percent), macroaneurysm (1.4 percent), bilateral papilledema (1.4 percent) and vitreous-retinal traction (1.4 percent). CONCLUSIONS: Patients with AIDS and neurotoxoplasmosis may present fundoscopic abnormalities characteristic of ocular toxoplasmosis, either in active or in scar form, related to HIV or even to other opportunist or systemic diseases, which can be of great aid for integral treatment of patients by a multiprofessional team.

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