RESUMO
Recently, it has been recommended that population-based studies report not only frequencies of vision impairment and blindness but also any ocular abnormalities that might lead an individual to seek for eyecare services. The current study aimed to determine prevalence of ocular findings regardless of visual acuity (VA) status in older adults from the Brazilian Amazon Region. Disturbances were grouped into: Eyelids; Anterior Segment; Posterior Segment; Increased intraocular pressure; and Overall Globe. The presence of an ocular finding was considered positive when any abnormality was noted, regardless of VA. Refractive errors were not considered. A total 2384 eligible persons were enumerated and 2041 (85.6%) examined. The prevalence of ocular disturbances in either eye was 87.0% and was associated with male gender, older age, lower education, and rural residence. Overall, main findings were pterygium, cataract, and pinguecula, occurring in 58.8%, 45.4% and 17.4%, respectively. Among individuals with 20/20 VA in both eyes, the most frequent findings were pterygium, pinguecula, and glaucoma cupping, occurring in 47.4%, 31.2% and 6.5%, respectively. The high prevalence of ocular findings observed in this population reinforces that different conditions might not immediately decrease VA but can indicate risk and/or discomfort symptoms and should be considered when planning public health ophthalmic services.
Assuntos
Oftalmopatias/epidemiologia , Avaliação Geriátrica/estatística & dados numéricos , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Brasil/epidemiologia , Oftalmopatias/diagnóstico , Oftalmopatias/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Vigilância da População , Prevalência , Fatores de Risco , Acuidade VisualRESUMO
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.
Assuntos
Vigilância da População , Pterígio/epidemiologia , Erros de Refração/epidemiologia , População Rural , Acuidade Visual , Distribuição por Idade , Idoso , Brasil/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Pterígio/complicações , Erros de Refração/etiologia , Erros de Refração/fisiopatologiaRESUMO
PURPOSE: To report a case of a child with strabismus and delayed discovery of a metallic intraocular foreign body with good recovery of visual acuity and stereopsis with 36-month follow-up. METHODS: A 4-year-old girl was evaluated due to exotropia of right eye initiated 9 months before with progressive worsening. Visual acuity was 1.00 logMAR (20/200) in the right eye and 0.00 logMAR (20/20) in the left eye. Anterior segment evidenced a small paracentral corneal leukoma, posterior synechia and mild lens opacity in the temporal quadrant only in the right eye. Fundus examination in the right eye identified the presence of an intraocular foreign body, with appearance of metallic components surrounded by retinal pigmented endothelial cells atrophy. Full-field electroretinography (ERG) showed reduced amplitudes and delayed implicit times for both rods and cones in the affected eye. All tests were normal in the fellow eye. RESULTS: Pars plana vitrectomy was promptly performed in the right eye, followed by phacoemulsification with intraocular lens implantation 4 months later due to worsening of the lens opacification. The full-field ERG was repeated after the surgical procedures. The ERG showed mild worsening of all responses in the right eye. After 36 months of follow-up, visual acuity was 0.20 logMAR (20/32) with improvement of the ocular misalignment and with 60 s of arc stereopsis with ERG responses unchanged. CONCLUSION: In this young girl perforating ocular trauma with metallic material was lately diagnosed with strabismus as a sign of alert. Prompt surgical intervention and proper management were essential to provide reasonable visual function including some degree of stereopsis, even though retinal dysfunction characterized by ERG was persistent.
Assuntos
Corpos Estranhos no Olho/diagnóstico , Ferimentos Oculares Penetrantes/diagnóstico , Metais , Retina/lesões , Atrofia , Pré-Escolar , Diagnóstico Tardio , Percepção de Profundidade/fisiologia , Eletrorretinografia , Exotropia/diagnóstico , Corpos Estranhos no Olho/fisiopatologia , Corpos Estranhos no Olho/cirurgia , Ferimentos Oculares Penetrantes/fisiopatologia , Ferimentos Oculares Penetrantes/cirurgia , Feminino , Humanos , Implante de Lente Intraocular , Facoemulsificação , Refração Ocular/fisiologia , Retina/fisiopatologia , Epitélio Pigmentado da Retina/patologia , Acuidade Visual/fisiologia , VitrectomiaRESUMO
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.
Assuntos
Cegueira/epidemiologia , Baixa Visão/epidemiologia , Pessoas com Deficiência Visual/estatística & dados numéricos , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Brasil/epidemiologia , Estudos Transversais , Oftalmopatias/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , População Rural/estatística & dados numéricos , Inquéritos e Questionários , População Urbana/estatística & dados numéricos , Testes Visuais , Acuidade Visual/fisiologiaRESUMO
This study was performed to evaluate a healthcare strategy based on teleophthalmology for diagnosis and management of primary healthcare users. A descriptive cross-sectional study was conducted to review the medical records of patients from January 2013 to December 2014 from primary care units in the city of São Paulo. The units referred patients, who had diabetes or high blood pressure, and were users of chloroquine compounds, for a fundus examination. The images were sent to a reading center for review, diagnosis, and patient referrals. From 9173 analyzed patients, 570 (6.2%) were excluded because of poor image quality. Of the remaining patients, 4933 (57.3%) had diabetes, 7242 (84,2%) systemic hypertension, and 113 (1.3%) used chloroquine. Of these, 989 (11.5%) patients needed ophthalmologic treatment. The most frequently prescribed treatments were cataract extraction in 692 (70%) of 989 and photocoagulation in 245 (24.8%) of 989 cases. Overall, cataract extraction was indicated in 692 (8%) of 8603 cases and photocoagulation in 245 (2.8%) of 8603 cases. When only patients with diabetes were considered, the indication for photocoagulation increased to 4.5%.The results showed that non-medical professionals could produce good-quality ocular images for screening of ocular diseases in most cases; only 6.2% of ocular images did not meet quality requirements. Most patients referred for fundus examination did not need a specific treatment, indicating that this system could be an inexpensive and reliable tool for use in developing countries.
RESUMO
Older adults living in remote areas with limited access to health services are at higher risk to develop visual impairment and blindness. We conducted a population-based survey to determine the vision status in subjects 45 years of age and older from urban and rural areas of Parintins city, Brazilian Amazon Region. Participants underwent ophthalmic examination, including uncorrected (UCVA), presenting (PVA) and best-corrected visual acuity (BCVA). Vision status was described as lines of visual acuity (VA) impairment and lines of VA improvement from UCVA to BCVA and from PVA to BCVA in the better-seeing eye. A total of 2384 subjects were enumerated, 2041 (85.6%) were examined, with reliable VA measurements obtained from 2025 participants. Vision status in lines of VA impairment was (mean ± standard deviation): 3.44 ± 3.53 for UCVA, 2.85 ± 3.52 for PVA and 1.50 ± 3.51 for BCVA. Female gender, older age and lower education were associated with ≥6 lines of UCVA impairment. Lines of improvement ≥3 was found in 626 (30.9%) participants and associated with female gender and rural residency. In conclusion, a third of participants could have at least three lines of VA improvement with proper refraction. Strategies to improve access to eye care and affordable glasses are needed.
Assuntos
População Rural/estatística & dados numéricos , Visão Ocular/fisiologia , Acuidade Visual/fisiologia , Distribuição por Idade , Idoso , Cegueira/fisiopatologia , Brasil , Estudos Transversais , Feminino , Inquéritos Epidemiológicos , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Distribuição por Sexo , Baixa Visão/fisiopatologiaRESUMO
PURPOSE: To describe the study design, operational strategies, procedures, and baseline characteristics of the Brazilian Amazon Region Eye Survey (BARES), a population-based survey of the prevalence and causes of distance and near visual impairment and blindness in older adults residing in the city of Parintins. METHODS: Cluster sampling, based on geographically defined census sectors, was used for cross-sectional random sampling of persons 45 years and older from urban and rural areas. Subjects were enumerated through a door-to-door survey and invited for measurement of uncorrected, presenting and best-corrected visual acuity and an ocular examination. RESULTS: Of 9931 residents (5878 urban and 4053 rural), 2384 individuals (1410 urban and 974 rural) were eligible and 2041 (1180 urban and 861 rural) had a clinical examination (response rate 85.6%). The majority of participants were female (1041, 51.0%); the average age was 59.9 ± 11.1 years (60.2 ± 11.2 years for urban and 59.4 ± 11.1 years for rural); 1360 (66.6%) had primary schooling or less (58.1% in urban and 78.4% in rural) and 57.8% were resident in urban areas. The age distribution between sexes was similar (p = 0.178). Both sex and age distributions of the sample were comparable to that of the Brazilian Amazon Region population. CONCLUSIONS: The BARES cohort will provide information about the prevalence and causes of near and distance vision in this underprivileged and remote population in Brazil.
Assuntos
Cegueira/epidemiologia , Inquéritos Epidemiológicos/métodos , População Rural/estatística & dados numéricos , População Urbana/estatística & dados numéricos , Baixa Visão/epidemiologia , Acuidade Visual , Distribuição por Idade , Brasil/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Distribuição por SexoRESUMO
PURPOSE: To determine uptake, barriers and outcomes in the follow-up of patients referred for free-of-charge, expedited cataract surgery in the Sao Paulo Eye Study (SPES). METHODS: SPES was a population-based study of urban, low-middle income residents aged ≥50 years. Presenting visual acuity (PVA), best-corrected visual acuity, refraction, and slit-lamp examination were performed in 3677 participants. For subjects with cataract as a principal cause of best-corrected visual acuity ≤20/40, surgery was offered free of charge. Two years after the baseline study, surgery uptake, barriers to surgery, and visual outcomes were analyzed. RESULTS: Among 210 (5.71%) participants who had a cataract surgery indication at baseline, 164 (78.1%) were successfully contacted and 55 (33.5%) reported being operated on for cataract, with 51 agreeing to be re-examined. In a multiple logistic regression model, age, sex, schooling, previous cataract surgery, and PVA at baseline were not significantly associated with surgery uptake. Co-existing health conditions (20.4%), fear of surgery (12.2%) and fear of losing eyesight (11.6%) were the most frequent barriers to cataract surgery adherence. Among the 69 eyes operated on in the interval between baseline and follow-up, PVA ≥20/63 was observed in 50 (72.6%, 95% confidence interval, CI, 62.2-82.3%), PVA <20/63-20/200 in 11 (15.8%, 95% CI 8.9-22.9%) and PVA <20/200 in 8 (11.6%, 95% CI 5.3-17.9%). CONCLUSIONS: Quality of surgery is an increasing determinant of uptake rates. Although free-of-charge and expedited cataract surgery was offered, surgical outcomes might have influenced the low uptake. Aside from cataract surgery campaigns, improvement of surgeon skills, accurate biometry, treatment of ocular comorbidities, postoperative follow-up and eye-care education are needed.
Assuntos
Extração de Catarata/economia , Extração de Catarata/estatística & dados numéricos , Assistência Médica , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Encaminhamento e Consulta , Idoso , Brasil/epidemiologia , Catarata/epidemiologia , Estudos Transversais , Feminino , Seguimentos , Acessibilidade aos Serviços de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Refração Ocular/fisiologia , Lâmpada de Fenda , Acuidade Visual/fisiologia , Pessoas com Deficiência Visual/estatística & dados numéricosRESUMO
PURPOSE: To investigate the pupillary light reflex (PLR) of patients with severe loss of vision due to Leber's Hereditary Optic Neuropathy (LHON) in the context of a proposed preservation of melanopsin-expressing retinal ganglion cells (mRGCs). METHODS: Ten LHON patients (7 males; 51.6 ± 14.1 years), with visual acuities ranging from 20/400 to hand motion perception and severe visual field losses, were tested and compared with 16 healthy subjects (7 males; 42.15 ± 15.4 years) tested as controls. PLR was measured with an eye tracker and the stimuli were controlled with a Ganzfeld system. Pupil responses were measured monocularly, to 1 second of blue (470 nm) and red (640 nm) flashes with 1, 10, 100, and 250 cd/m² luminances. The normalized amplitude of peak of the transient PLR and the amplitude of the sustained PLR at 6 seconds after the flash offset were measured. In addition, optical coherence topography (OCT) scans of the peripapillary retinal nerve fiber layer were obtained. RESULTS: The patient's peak PLR responses were on average 15% smaller than controls (P < 0.05), but 5 out of 10 patients had amplitudes within the range of controls. The patients' sustained PLRs were comparable with controls at lower flash intensities, but on average, 27% smaller to the 250 cd/m² blue light, although there was considerable overlap with the PLR amplitudes of control. All patients had severe visual field losses and the retinal nerve fiber layer thickness was reduced to a minimum around the optic disc in 8 of the 10 patients. CONCLUSIONS: The PLR is maintained overall in LHON patients despite the severity of optic atrophy. These results are consistent with previous evidence of selective preservation of mRGCs.
Assuntos
Atrofia Óptica Hereditária de Leber/fisiopatologia , Reflexo Pupilar/fisiologia , Células Ganglionares da Retina/metabolismo , Opsinas de Bastonetes/metabolismo , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estimulação Luminosa/métodos , Células Ganglionares da Retina/patologia , Tomografia de Coerência ÓpticaRESUMO
PURPOSE: Neuron-specific enolase (NSE) is a biomarker for neuronal stress. Leber's hereditary optic neuropathy (LHON) is a mitochondrial disease affecting retinal ganglion cells (RGC). These RGCs and their axons in the retinal nerve fiber layer (RNFL) and optic nerve head may show subclinical pathology in unaffected mutation carriers, or undergo cell death in affected patients. We hypothesize that increased levels of blood NSE may characterize LHON carriers as a biomarker of ongoing RGC stress. METHODS: Serum was obtained from 74 members of a Brazilian pedigree with LHON carrying the homoplasmic 11778/ND4 mitochondrial DNA mutation. Classified by symptoms and psychophysical metrics, 46/74 patients were unaffected mutation "carriers," 14/74 were "affected," and 14/74 were "off-pedigree" controls. Serum NSE levels were determined by ELISA specific for the γ subunit of NSE. RESULTS: Serum NSE concentrations in carriers (27.17 ± 39.82 µg/L) were significantly higher than affected (5.66 ± 4.19 µg/L; P = 0.050) and off-pedigree controls (6.20 ± 2.35 µg/L; P = 0.047). Of the 14/46 (30.4 %) carriers with significantly elevated NSE levels (mean = 75.8 ± 42.3 µg/L), 9/14 (64.3%) were male. Furthermore, NSE levels were nearly three times greater in asymptomatic male carriers (40.65 ± 51.21 µg/L) than in asymptomatic female carriers (15.85 ± 22.27 µg/L; P = 0.034). CONCLUSIONS: Serum NSE levels are higher in LHON carriers compared with affected and off-pedigree individuals. A subgroup of mostly male carriers had significantly elevated serum NSE levels. Thus, male carriers are at higher risk for LHON-related neuronal stress.
Assuntos
Doenças Assintomáticas/epidemiologia , Atrofia Óptica Hereditária de Leber/epidemiologia , Atrofia Óptica Hereditária de Leber/metabolismo , Fosfopiruvato Hidratase/sangue , Brasil/epidemiologia , DNA Mitocondrial/genética , Saúde da Família , Feminino , Humanos , Masculino , Atrofia Óptica Hereditária de Leber/genética , Linhagem , Fatores de Risco , Distribuição por Sexo , Estresse Fisiológico/fisiologiaRESUMO
Being the commonest ocular disorder, dense cataracts disable fundoscopic examination and the diagnosis of retinal disorders, which dogs may be predisposed. The aim of this study was to compare the electroretinographic responses recorded according to the International Society for Clinical Electrophysiology of Vision human protocol to evaluate retinal function of diabetic and non diabetic dogs, both presenting mature or hypermature cataracts. Full-field electroretinogram was recorded from 66 dogs, with ages varying from 6 to 15 years old allocated into two groups: (1) CG, non diabetic cataractous dogs, and (2) DG, diabetic cataractous dogs. Mean peak-to-peak amplitude (microvolts) and b-wave implicit time (milliseconds) were determined for each of the five standard full-field ERG responses (rod response, maximal response, oscillatory potentials, single-flash cone response and 30 Hz flicker). Comparing CG to DG, ERGs recorded from diabetic dogs presented lower amplitude and prolonged b-wave implicit time in all ERG responses. Prolonged b-wave implicit time was statistically significant (p< 0.05) at 30 Hz flicker (24.0 ms versus 22.4 ms). These data suggests full-field ERG is capable to record sensible alterations, such as flicker's implicit time, being useful to investigate retinal dysfunction in diabetic dogs.(AU)
Catarata madura e hipermadura, alteração frequentemente observada em cães, impossibilita a visibilização do fundo do olho e provável diagnóstico de degenerações retinianas. Objetivou-se comparar as respostas retiniana de cães diabéticos e não diabéticos, ambos portadores de catarata madura ou hipermadura, com auxílio do eletrorretinograma de campo total, utilizando o protocolo da International Society for Clinical Electrophysiology of Vision. Sessenta e seis cães, com idades variando entre 6 a 15 anos de idade foram divididos em dois grupos: (1) CG, cães não diabéticos com catarata madura ou hipermadura e (2) DG, cães diabéticos com catarata madura ou hipermadura. Mensurou-se amplitude pico a pico (microvolts) e tempo de culminação da onda-b (milisegundos) para as cinco respostas do ERG (resposta de bastonetes, máxima resposta, potencial oscilatório, resposta de cones e flicker a 30Hz). Avaliando-se as respostas obtidas com o exame, o grupo de cães diabéticos apresentou menor amplitude e maior tempo de culminação da onda-b em todas as respostas. O aumento do tempo de culminação da onda-b em DG foi estatisticamente significante (p<0.05) no flicker a 30 Hz (24.0ms versus 22.4ms). ERG de campo total é capaz de registrar alterações em respostas sensíveis como o tempo de culminação da onda-b do flicker, podendo ser útil para investigar retinopatias em cães diabéticos.(AU)
Assuntos
Cães , Eletrorretinografia/métodos , Eletrorretinografia/tendências , Eletrorretinografia/veterinária , Catarata/veterináriaRESUMO
Being the commonest ocular disorder, dense cataracts disable fundoscopic examination and the diagnosis of retinal disorders, which dogs may be predisposed. The aim of this study was to compare the electroretinographic responses recorded according to the International Society for Clinical Electrophysiology of Vision human protocol to evaluate retinal function of diabetic and non diabetic dogs, both presenting mature or hypermature cataracts. Full-field electroretinogram was recorded from 66 dogs, with ages varying from 6 to 15 years old allocated into two groups: (1) CG, non diabetic cataractous dogs, and (2) DG, diabetic cataractous dogs. Mean peak-to-peak amplitude (microvolts) and b-wave implicit time (milliseconds) were determined for each of the five standard full-field ERG responses (rod response, maximal response, oscillatory potentials, single-flash cone response and 30 Hz flicker). Comparing CG to DG, ERGs recorded from diabetic dogs presented lower amplitude and prolonged b-wave implicit time in all ERG responses. Prolonged b-wave implicit time was statistically significant (p< 0.05) at 30 Hz flicker (24.0 ms versus 22.4 ms). These data suggests full-field ERG is capable to record sensible alterations, such as flicker's implicit time, being useful to investigate retinal dysfunction in diabetic dogs.
Catarata madura e hipermadura, alteração frequentemente observada em cães, impossibilita a visibilização do fundo do olho e provável diagnóstico de degenerações retinianas. Objetivou-se comparar as respostas retiniana de cães diabéticos e não diabéticos, ambos portadores de catarata madura ou hipermadura, com auxílio do eletrorretinograma de campo total, utilizando o protocolo da International Society for Clinical Electrophysiology of Vision. Sessenta e seis cães, com idades variando entre 6 a 15 anos de idade foram divididos em dois grupos: (1) CG, cães não diabéticos com catarata madura ou hipermadura e (2) DG, cães diabéticos com catarata madura ou hipermadura. Mensurou-se amplitude pico a pico (microvolts) e tempo de culminação da onda-b (milisegundos) para as cinco respostas do ERG (resposta de bastonetes, máxima resposta, potencial oscilatório, resposta de cones e flicker a 30Hz). Avaliando-se as respostas obtidas com o exame, o grupo de cães diabéticos apresentou menor amplitude e maior tempo de culminação da onda-b em todas as respostas. O aumento do tempo de culminação da onda-b em DG foi estatisticamente significante (p<0.05) no flicker a 30 Hz (24.0ms versus 22.4ms). ERG de campo total é capaz de registrar alterações em respostas sensíveis como o tempo de culminação da onda-b do flicker, podendo ser útil para investigar retinopatias em cães diabéticos.
Assuntos
Cães , Catarata/veterinária , Eletrorretinografia/métodos , Eletrorretinografia/tendências , Eletrorretinografia/veterináriaRESUMO
Our purpose is to provide a summary overview of blindness and visual impairment on the context of recent Brazilian ocular epidemiologic studies. Synthesis of data from two cross-sectional population-based studies - the São Paulo Eye Study and the Refractive Error in School Children Study is presented. 3678 older adults and 2441 school children were examined between July 2004 and December 2005. Prevalence of blindness in older adults using presenting visual acuity was 1.51% decreasing to 1. 07% with refractive correction. The most common causes of blindness in older adults were retinal disorders, followed by cataract and glaucoma. In school children, the prevalence of uncorrected visual impairment was 4.82% decreasing to 0.41% with refractive correction. The most common cause of visual impairment in school children was uncorrected refractive error. Visual impairment and blindness in Brazil is an important public health problem. It is a significant problem in older Brazilians, reinforcing the need to implement prevention of blindness programs for elderly people with emphasis on those without schooling. In school-children cost-effective strategies are needed to address a readily treatable cause of vision impairment - prescription and provision of glasses.
Assuntos
Transtornos da Visão/epidemiologia , Adulto , Cegueira/epidemiologia , Cegueira/etiologia , Brasil/epidemiologia , Criança , Estudos Transversais , Humanos , Prevalência , Transtornos da Visão/etiologia , Acuidade VisualRESUMO
Our purpose is to provide a summary overview of blindness and visual impairment on the context of recent Brazilian ocular epidemiologic studies. Synthesis of data from two cross-sectional population-based studies - the São Paulo Eye Study and the Refractive Error in School Children Study is presented. 3678 older adults and 2441 school children were examined between July 2004 and December 2005. Prevalence of blindness in older adults using presenting visual acuity was 1.51 percent decreasing to 1. 07 percent with refractive correction. The most common causes of blindness in older adults were retinal disorders, followed by cataract and glaucoma. In school children, the prevalence of uncorrected visual impairment was 4.82 percent decreasing to 0.41 percent with refractive correction. The most common cause of visual impairment in school children was uncorrected refractive error. Visual impairment and blindness in Brazil is an important public health problem. It is a significant problem in older Brazilians, reinforcing the need to implement prevention of blindness programs for elderly people with emphasis on those without schooling. In school-children cost-effective strategies are needed to address a readily treatable cause of vision impairment - prescription and provision of glasses.
Nosso objetivo é fazer uma revisão de cegueira e deficiência visual no contexto de recentes estudos epidemiológicos oculares brasileiros. É apresentada a síntese dos dados de dois estudos populacionais transversais - o Estudo Ocular de São Paulo e o Estudo de Erros Refrativos em Escolares. Entre julho de 2004 e dezembro de 2005 foram examinados 3678 adultos e 2441 escolares. A prevalência de cegueira em adultos mais velhos considerando a acuidade visual apresentada foi de 1, 51 por cento diminuindo para 1, 07 por cento com a correção refrativa. As causas mais comuns de cegueira em adultos mais velhos foram os distúrbios de retina, seguidos de catarata e glaucoma. Em escolares a prevalência de deficiência visual não corrigida foi de 4,82 por cento diminuindo para 0,41 por cento com a correção refrativa. Em escolares a causa mais comum de deficiência visual foram erros refrativos não corrigidos. A deficiência visual e a cegueira são um importante problema de saúde pública no Brasil. É um problema significante em brasileiros mais velhos reforçando a necessidade de implementação de programas de prevenção de cegueira para pessoas idosas com ênfase nos indivíduos sem escolaridade. Em escolares são necessárias estratégias de custo-eficácia para atingir uma causa de deficiência visual facilmente tratável - a prescrição e a provisão de óculos.
Assuntos
Adulto , Criança , Humanos , Transtornos da Visão/epidemiologia , Cegueira/epidemiologia , Cegueira/etiologia , Brasil/epidemiologia , Estudos Transversais , Prevalência , Acuidade Visual , Transtornos da Visão/etiologiaRESUMO
PURPOSE: To investigate the prevalence and visual acuity (VA) outcomes of cataract surgery in a low- to middle-income population in São Paulo, Brazil. DESIGN: Population-based, cross-sectional study. METHODS: Cluster sampling was used in randomly selecting those > or =50 years old for VA measurement, refraction, and ocular examination. Participants were queried as to the year and type of facility for previous cataract surgery. Surgical procedure and evidence of surgical complications were noted. Main outcome measures were presenting and best-corrected vision, and the principal cause for eyes presenting with VA < or =20/40. RESULTS: A total of 4,224 eligible persons were enumerated and 3,678 (87.1%) were examined. The prevalence of cataract surgery was 6.28% (95% confidence interval [CI], 5.29% to 7.27%). Surgical coverage for presenting VA <20/63 in both eyes because of cataract was 61.4%. Unoperated cataract impairment/blindness was associated with older age and lack of schooling. Among the 352 cataract-operated eyes, 41.2% presented with VA >20/40, 28.1% with VA 20/40 to 20/63, 14.2% with VA <20/63 to 20/200, and 16.5% with VA <20/200. With best correction, the percentages were 61.9%, 17.6%, 8.2%, and 12.2%. Intraocular lenses were found in 90.6% of cataract-operated eyes; half appeared to have been operated by phacoemulsification. Refractive error and retinal disorders were the main cause of vision impairment/blindness in operated eyes. CONCLUSIONS: Cataract surgery has increased in São Paulo, but many remain visually impaired/blind because of cataract. Refractive error and other causes of impairment are common in cataract-operated eyes. Emphasis on the quality of VA outcomes and sustained government subsidy to provide access to affordable modern cataract surgery are needed.
Assuntos
Afacia Pós-Catarata/epidemiologia , Extração de Catarata/estatística & dados numéricos , Catarata/epidemiologia , Implante de Lente Intraocular/estatística & dados numéricos , Pseudofacia/epidemiologia , Acuidade Visual/fisiologia , Idoso , Brasil/epidemiologia , Estudos Transversais , Feminino , Humanos , Renda , Masculino , Pessoa de Meia-Idade , Prevalência , Resultado do TratamentoRESUMO
PURPOSE: To study the optic nerve head (ONH) morphology of patients with Leber's hereditary optic neuropathy (LHON) in a large family from Brazil carrying the 11778/ND4 mutation and in a case series of unrelated Italian families bearing different mitochondrial DNA (mtDNA) pathogenic mutations. METHODS: Enrolled in the study were 15 LHON-affected patients (LHON-affected) and 45 LHON unaffected mutation carriers (LHON carriers) belonging to the previously reported Brazilian SOA-BR LHON pedigree and 56 LHON-affected and 101 LHON carriers from 45 unrelated LHON Italian pedigrees molecularly defined. The LHON-affected were subgrouped according to the extent of visual recovery. All individuals underwent optic nerve head (ONH) analysis by optical coherence tomography. RESULTS: In the Brazilian sample, the mean optic disc area was significantly larger in LHON carriers than in the control group (P=0.002). In the Italian sample, the mean optic disc area and vertical disc diameter were significantly higher in LHON carriers than in both LHON-affected (respectively, P=0.008 and P<0.001) and control subjects (P<0.001 in both cases). The LHON-affected with visual recovery had a significantly larger vertical disc diameter when compared with those without visual recovery (P=0.03). CONCLUSIONS: The results, revealing that the ONH size is larger in LHON carriers than in LHON-affected, suggest a protective role for this anatomic trait. Such a hypothesis is reinforced by the observation that, among the LHON-affected, larger discs correlated with visual recovery and better visual outcome. The findings may be relevant for prognosis and provide a mechanism for identifying nuclear-modifying genes implicated in the variability of penetrance in LHON.
Assuntos
Atrofia Óptica Hereditária de Leber/diagnóstico , Disco Óptico/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Análise Mutacional de DNA , DNA Mitocondrial/genética , Progressão da Doença , Feminino , Heterozigoto , Humanos , Masculino , Pessoa de Meia-Idade , Atrofia Óptica Hereditária de Leber/genética , Linhagem , Penetrância , Prognóstico , Tomografia de Coerência ÓpticaRESUMO
PURPOSE: Assess prevalence and causes of vision impairment among low-middle income school children in São Paulo. METHODS: Cluster sampling was used to obtain a random sample of children ages 11 to 14 years from public schools (grades 5-8) in three districts from June to November 2005. The examination included visual acuity testing, ocular motility, and examination of the external eye, anterior segment, and media. Cycloplegic refraction and fundus examination were performed in children with uncorrected visual acuity 20/40 or worse in either eye. A principal cause of visual impairment was determined for eyes with uncorrected visual acuity of 20/40 or worse. RESULTS: A total of 2825 children were enumerated and 2441 (86.4%) were examined. The prevalence of uncorrected, presenting, and best-corrected visual acuity 20/40 or worse in the better eye was 4.82%, 2.67%, and 0.41%, respectively. Spectacles were used by 144 (5.9%) children. Refractive error was a cause in 76.8% of children with visual impairment in one or both eyes; amblyopia, 11.4%; retinal disorders, 5.9%; other causes, 2.7%; and unexplained causes, 7.7%. Myopic visual impairment (spherical equivalent -0.50 D in one or both eyes) was not associated with age or grade level, but female sex was marginally significant (P = 0.070). Hyperopic visual impairment (+2.00 D or more) was not associated with age, grade level, or sex. CONCLUSIONS: The prevalence of reduced vision in low-middle income urban São Paulo school children was low, most of it because of uncorrected refractive error. Cost-effective strategies are needed to address this easily treated cause of vision impairment.
Assuntos
Erros de Refração/epidemiologia , Classe Social , Transtornos da Visão/epidemiologia , Pessoas com Deficiência Visual/estatística & dados numéricos , Adolescente , Brasil/epidemiologia , Criança , Movimentos Oculares , Óculos/estatística & dados numéricos , Feminino , Humanos , Masculino , Prevalência , Erros de Refração/complicações , Transtornos da Visão/etiologia , Testes Visuais , Acuidade VisualRESUMO
PURPOSE: Investigate prevalence and causes of vision impairment/blindness in older adults in a low-middle income area of Sao Paulo, Brazil. METHODS: Cluster sampling, based on geographically defined census sectors, was used in randomly selecting cross-sectionally persons 50 years of age or older. Subjects were enumerated through a door-to-door survey and invited for measurement of presenting and best-corrected visual acuity and an ocular examination. The principal cause was identified for eyes with presenting visual acuity less than 20/32. RESULTS: A total of 4,224 eligible persons in 2,870 households were enumerated, and 3,678 (87.1%) examined. The prevalence of presenting visual acuity > or = 20/32 in both eyes was 61.6% (95% confidence interval [CI]: 59.4%-63.9%), and 80.4% (95% CI: 78.8%-82.1%) with best correction. The prevalence of visual impairment (< 20/63 to > or =20/200) in the better eye was 4.74% (95% CI: 3.97%-5.53%), and 2.00% (95% CI: 1.52%-2.49%) with best correction. The prevalence of presenting bilateral blindness (< 20/200) was 1.51% (95% CI: 1.20%-1.82%), and 1.07% (95% CI: 0.79%-1.35%) with best correction. Presenting blindness was associated with older age and lack of schooling. Retinal disorders (35.3%) and cataract (28.3%) were the most common causes of blind eyes. Cataract (33.2%), refractive error (32.3%), and retinal disorders (20.3%) were the main causes of vision impairment < 20/63 to > or = 20/200, with refractive error (76.8%) and cataract (12.2%) as main causes for eyes with acuity < 20/32 to > or = 20/63. CONCLUSIONS: Vision impairment is a significant problem in older Brazilians reinforcing the need to implement prevention of blindness programs for elderly people with emphasis on those without schooling.
Assuntos
Cegueira/epidemiologia , Cegueira/etiologia , Transtornos da Visão/epidemiologia , Transtornos da Visão/etiologia , Distribuição por Idade , Idoso , Brasil/epidemiologia , Catarata/complicações , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Erros de Refração/complicações , Doenças Retinianas/complicações , Transtornos da Visão/fisiopatologia , Visão Binocular , Acuidade VisualRESUMO
Leber Hereditary Optic Neuropathy (LHON) is a maternally inherited blinding disease caused by missense mutations in the mitochondrial DNA (mtDNA). However, incomplete penetrance and a predominance of male patients presenting with vision loss suggest that modifying factors play an important role in the development of the disease. Evidence from several studies suggests that both nuclear modifier genes and environmental factors may be necessary to trigger the optic neuropathy in individuals harboring an LHON-causing mtDNA mutation. Recently, an optic neuropathy susceptibility locus at Xp21-Xq21 has been reported. In this study, we performed X-chromosomal linkage analysis in a large Brazilian family harboring a homoplasmic G11778A mtDNA mutation on a haplogroup J background. We report the identification of a novel LHON susceptibility locus on chromosome Xq25-27.2, with multipoint non-parametric linkage scores of > 5.00 (P = 0.005) and a maximum two-point non-parametric linkage score of 10.12, (P = 0.003) for marker DXS984 (Xq27.1). These results suggest genetic heterogeneity for X-linked modifiers of LHON.
Assuntos
Cromossomos Humanos X , Ligação Genética , Predisposição Genética para Doença , Atrofia Óptica Hereditária de Leber/genética , Brasil , Mapeamento Cromossômico , DNA Mitocondrial/genética , Feminino , Humanos , Masculino , Mutação , LinhagemRESUMO
PURPOSE: Leber's hereditary optic neuropathy (LHON) is a maternally inherited disease resulting in loss of central vision and dyschromatopsia, caused by mitochondrial DNA point mutations. However, only a subset of the mutation carriers becomes affected, with a higher penetrance in males. This study was conducted to investigate chromatic losses in asymptomatic carriers of the LHON mutation. METHODS: Monocular chromatic discrimination was studied with the Cambridge Colour Test (CCT; Cambridge Research Systems, Ltd., Rochester, UK) along the protan, deutan, and tritan cone isolation axes in 46 LHON carriers (15 men) belonging to the same LHON maternal lineage and 74 age-matched control subjects (39 men). Inclusion criteria were absence of ophthalmic complaints and clear ocular media. A detailed neuro-ophthalmic examination was performed in all the LHON carriers. RESULTS: The differences in threshold between carriers and control subjects were significant for the three cone isolation axes at P < 0.0001. Sixty-five percent of the carriers had abnormal protan and/or deutan thresholds; some of those with higher thresholds also had elevated tritan thresholds (13%). The male thresholds were higher and more frequent than those of the women for the protan and deutan axes (ANOVA; P < 0.05), but not for tritan thresholds. In the most severe losses, the women had instances of diffuse defect whereas all the men displayed a red-green defect. CONCLUSIONS: Male LHON asymptomatic carriers had color vision losses with the red-green pattern of dyschromatopsia typical of patients affected with LHON, which includes elevation of tritan thresholds as well. This predominantly parvocellular (red-green) impairment is compatible with the histopathology of LHON, which affects mostly the papillomacular bundle. In contrast with male losses, female losses were less frequent and severe. These gender differences are relevant to understanding LHON pathophysiology, suggesting that hormonal factors may be of great importance.