Pterygium in adults from the Brazilian Amazon Region: prevalence, visual status and refractive errors.

AIMS: To determine prevalence of pterygium, its role as main cause of unilateral and bilateral visual impairment and blindness and its impact on refractive errors from adults living in a high ultraviolet exposure area in the Brazilian Amazon Region. METHODS: Cluster sampling was used in randomly selecting subjects ≥45 years of age from urban and rural areas of Parintins city. Eligible subjects were enumerated through a door-to-door household survey and invited for an eye exam including refraction. Pterygium was assessed considering location (nasal, temporal or both) and size (<3 mm or ≥3 mm reaching or not pupillary margin). RESULTS: A total of 2384 persons were enumerated and 2041 (85.6%) were examined. Prevalence of pterygium was 58.8% (95% CI 53.8% to 63.7%) and associated with male gender (OR=1.63; 95% CI 1.37 to 1.94; p=0.001), while higher education was a protective factor (OR=0.63; 95% CI 0.44 to 0.92; p=0.018). Older age and rural residence were associated with pterygium ≥3 mm reaching or not pupillary margin, while higher education was a protective factor for pterygium ≥3 mm reaching pupillary margin. Prevalence of pterygium as cause of visual impairment and blindness was 14.3% and 3.9%, respectively. Significantly higher hyperopic refractive errors were found in eyes with pterygium ≥3 mm reaching or not pupillary margin. CONCLUSIONS: Pterygium was highly prevalent and the second cause of visual impairment and blindness after provision of refractive correction. Risk factors for pterygium were male gender, advanced age, lower education and rural residency. Strategies to provide pterygium early detection and proper management should be considered by healthcare authorities in this population.

Prevalence and Causes of Visual Impairment and Blindness in Adults Aged 45 Years and Older from Parintins: The Brazilian Amazon Region Eye Survey.

Purpose: To determine the prevalence and causes of visual impairment and blindness in adults aged 45 years and older from Parintins, Brazilian Amazon Region. Methods: A random cluster sampling method was used to identify subjects 45 years of age and older from urban and rural census sectors of Parintins city, Amazonas State, from March 2014 to May 2015. Participants underwent a detailed ocular examination, including presenting (PVA) and best corrected visual acuity (BCVA). The main cause of PVA<20/32 per eye was determined. Results: A total of 2384 subjects were enumerated and 2041 (85.6%) examined. The prevalence of presenting mild visual impairment - MiVI (<20/32 - ≥20/63) in the better-seeing eye was 17.0% [95% CI: 15.3-18.7%], and 8.5% [95% CI: 7.3-9.7%] with best correction. The prevalence of presenting moderate visual impairment - MVI (<20/63 - ≥20/200) was 18.4% [95% CI: 16.2-20.6%], and 6.9% [95% CI: 5.8-8.0%] with best correction. The prevalence of presenting bilateral VA <20/200 was 4.3% [95% CI: 3.6-5.0%], and 3.3% [95% CI: 2.5-4.0%] with best correction and increased with older age. Cataract (47.8%) and glaucoma (7.5%) were its main causes. In less severely affected eyes, uncorrected refractive errors (MVI: 42.6%; MiVI: 79.0%), cataract (MVI: 40.6%; MiVI: 13.7%) and pterygium (MVI: 7.6%; MiVI: 2.7%) were the main causes. Conclusions: Most cases of visual impairment in Parintins are either preventable or treatable, and public health initiatives should target cataract surgical services and refraction with spectacle provision.

Retina assessment by optical coherence tomography of diabetic dogs / Avaliação da retina de cães diabéticos pela tomografia de coerência óptica

Diabetes mellitus is one of the most common endocrine disorders characterized by relative or absolute lack of insulin; this can lead to several ocular manifestations, among them diabetic retinopathy and cataracts. Diabetic retinopathy (DR) is a microangiopathy that involves retinal precapillary arterioles, postcapillary venules, and large vessels, causing them to be functionally and anatomically incompetent. Hyperglycemia seems to be the most probable cause of damage to the retina due to interference in cellular metabolism and transduction processes. The aim of this study was to evaluate retinal thickness in eight diabetic dogs, four females and four males of different breeds and ages ranging from 6 to 15 years, by optical coherence tomography (OCT) and to compare them with non-diabetic dogs. Assessment provided by OCT in diabetic dogs showed retinal layers thinning and loss of stratification when compared to non-diabetic dogs (198μm versus 219μm respectively), with statistical significance (p=0.008). OCT images may suggest that diabetes mellitus causes retinal neuropathy in dogs, as also seen in diabetic humans.(AU)

Diabete melito é umas das principais endocrinopatias, caracterizada pela deficiência relativa ou absoluta de insulina, que pode resultar em diversas manifestações oculares, sendo as mais frequentes a retinopatia diabética e a catarata. Retinopatia diabética (RD) é uma microangiopatia que afeta primeiramente as arteríolas pré-capilares, capilares, vênulas pós-capilares e vasos de maior calibre, causando incompetência funcional e anatômica dos vasos retinianos. A hiperglicemia parece ser a causa mais provável da lesão retiniana, interferindo nas vias de metabolismo celular e no processo de transdução. Objetivou-se neste estudo avaliar e comparar a espessura retiniana total em oito cães diabéticos, quatro fêmeas e quatro machos, de diversas raças, com idade variando de seis a 15 anos, com auxílio de tomografia de coerência óptica (OCT) e comparar com a de cães não diabéticos. A espessura e arquitetura retiniana realizada pela OCT nos cães diabéticos, demonstrou afinamento das camadas da retina e perda da estratificação em comparação com os cães não diabéticos (198μm versus 219μm, respectivamente), sendo esta redução estatisticamente significante (p=0,008). Baseado nas imagens da OCT pode-se sugerir que a diabete melito, no cão, cause neuropatia retiniana como descrito em humanos diabéticos.(AU)