Ambliopia severa na infância relacionada à persistência da vasculatura fetal / Severe childhood amblyopia associated to persistence of fetal vasculature

RESUMO A persistência do vítreo primário hiperplásico, atualmente referida como persistência da vasculatura fetal, é uma anomalia congênita que resulta da não regressão do vítreo vascular primário e do sistema da artéria hialoide durante a embriogênese. Trata-se de uma anomalia unilateral na maioria dos casos, esporádica e comumente não associada a nenhum outro achado sistêmico. Clinicamente, essa condição pode ser classificada em persistência anterior e em persistência posterior da vasculatura fetal. A condição anterior está relacionada ao sistema da artéria ciliar, enquanto a persistência da vasculatura posterior associa-se à artéria hialoide e pode apresentar anormalidades, com desfecho visual desfavorável. A detecção da persistência do vítreo primário hiperplásico é de suma importância, visto que é um diagnóstico diferencial para retinoblastoma. O relato de caso a seguir descreve o acompanhamento ambulatorial em um Serviço de Oftalmologia de uma criança do sexo masculino com persistência da vasculatura fetal unilateral e sem alterações sistêmicas.

ABSTRACT Hyperplastic primary vitreous persistence, currently referred to as fetal vasculature persistence, is a congenital anomaly that results from non-regression of the primary vascular vitreous and hyaloid artery system during embryogenesis. It is a unilateral anomaly in the vast majority of cases, sporadic and commonly not associated with any other systemic finding. Clinically, this condition can be classified into anterior and posterior persistence of fetal vasculature. The anterior condition is related to the ciliary artery system, while the persistence of the posterior vasculature is associated with the hyaloid artery, which may present abnormalities with an unfavorable visual outcome. Detecting persistent hyperplastic primary vitreous is of paramount importance, as it is a differential diagnosis for retinoblastoma. The following case report describes the outpatient follow-up at the ophthalmology service of the Federal University of Triângulo Mineiro (UFTM) of a male child with persistent unilateral fetal vasculature and no systemic changes.

Anterior chamber depth and axial length affect clinical performance of Spot Vision Screener / A profundidade da câmara anterior e o comprimento axial afetam o desempenho clínico do Spot Vision Screener

ABSTRACT Purpose: The aim of this study was to evaluate the effect of anterior chamber depth and axial length on clinical performance of the Spot Vision Screener in detecting amblyopia risk factors in children aged 3-10 years. Methods: A total of 300 eyes from 150 patients aged 3-10 years were prospectively tested with Spot Vision Screener (firmware version 3.0.02.32, software version 3.0.04.06) and a standard autorefractometer (Nidek ARK-1). The anterior chamber depth and axial length were measured with an optical biometer (Nidek AL-Scan). The sensitivity and specificity values for detecting significant refractive errors using the referral criteria of the American Association for Pediatric Ophthalmology and Strabismus were determined. Pearson's correlation analysis was employed to evaluate the relationship between the Spot Vision results and the anterior chamber depth and axial length. Results: Compared with the standard autorefractometer results, the Spot Vision Screener's sensitivity and specificity was 59% and 94%, respectively. The differences between the cycloplegic autorefractometer and the Spot Vision Screener spherical equivalents were negatively correlated with anterior chamber depth (r=-0.48; p<0.001) and axial length (r=-0.45; p<0.001). Conclusion: The Spot Vision Screener has moderate sensitivity and high specificity, using the criteria of the American Association for Pediatric Ophthalmology and Strabismus. The anterior chamber depth and axial length affect the Spot Vision results.

RESUMO Objetivo: O objetivo deste estudo foi avaliar o efeito da profundidade da câmara anterior e do comprimento axial sobre o desempenho clínico do Spot Vision Screener, na deteção de fatores de risco para a ambliopia em crianças de 3 a 10 anos de idade. Métodos: Um total de 300 olhos de 150 pacientes de 3-10 anos de idade foram prospectivamente testados com o Spot Vision Screener (firmware: 3.0.02.32, software: 3.0.04.06) e com autorefratómetro padrão (Nidek ARK-1). Todas as medições de profundidade e comprimento axial da câmara anterior dos pacientes foram realizadas através de Nidek AL Scan. A sensibilidade e especificidade para a deteção de erros refrativos significativos foram determinadas de acordo com os critérios de referência da Associação Americana de Oftalmologia e Estrabismo Pediátricos. A análise da Correlação de Pearson foi utilizada para avaliar a correlação entre os resultados do Spot Vision e a profundidade ou comprimento axial da câmara anterior dos pacientes. Resultados: Em comparação com os resultados do autorefratómetro padrão, a sensibilidade do Spot foi de 59% e a especificidade de 94%. As diferenças entre os equivalentes esféricos do autorefratómetro cicloplégico e o Spot Vision Screener foram correlacionados negativamente com a profundidade (r=-0,48; p<0,001) e o comprimento axial (r=-0,45; p<0,001) da câmara anterior dos casos. Conclusão: O Spot Vision Screener possui uma sensibilidade moderada e uma especificidade elevada utilizando os critérios da Associação Americana de Oftalmologia Pediátrica e Estrabismo; a profundidade da câmara anterior e o comprimento axial dos pacientes afetam os resultados do Spot Vision.

Amblyopia: neural basis and therapeutic approaches / Ambliopia: bases neurais e intervenções terapêuticas

ABSTRACT Abnormalities in visual processing caused by visual deprivation or abnormal binocular interaction may induce amblyopia, which is characterized by reduced visual acuity. Occlusion therapy, the conventional treatment, requires special attention as occlusion of the fellow normal eye may reduce its visual acuity and impair binocular vision. Besides recovering visual acuity, some researchers have recommended restoration of stereoacuity and motor fusion and reverse suppression in order to prevent diplopia. Recent studies have documented that the amblyopic visual cortex has a normal complement of cells but reduced spatial resolution and a disordered topographical map. Changes occurring in the late sensitive period selectively impact the parvocellular pathway. Distinct morphophysiologic and psychophysical deficits may demand individualization of therapy, which might provide greater and longer-lasting residual plasticity in some children.

RESUMO Anormalidades nos processamentos visuais causadas por privação visual ou interação binocular anormal podem gerar ambliopia, caracterizada por redução da acuidade visual. A terapia de oclusão (tratamento convencional) necessita de cuidados especiais, pois a oclusão do olho normal (não-amblíope) pode reduzir a acuidade visual do mesmo e prejudicar a visão binocular. Além de recuperar a acuidade visual, alguns pesquisadores alertam para a necessidade em potencial de se restaurar a estereoacuidade e a fusão motora, bem como reverter a supressão a fim de impedir diplopia. Estudos recentes revelam que nos córtices visuais de amblíopes há uma quantidade normal de células, mas com resolução espacial reduzida e mapa topográfico desorganizado. Alterações ocorridas durante o período crítico tardio do desenvolvimento visual humano impactam seletivamente a via parvocelular. Déficits morfofisiológicos e psicofísicos distintos podem exigir programas de tratamento potencialmente seletivos e poderiam explicar a plasticidade residual maior e mais duradoura em algumas crianças.

Unusual ocular manifestations of silent sinus syndrome / Manifestações oculares incomuns na síndrome do seio silencioso

Silent sinus syndrome is an acquired condition in which there is a gradual collapse of the orbital floor and inward retraction of the maxillary sinus (atelectasis of the maxillary sinus). This in turn may cause associated ocular occurrences of enophthalmos and hypotropia. This is a report of an 8 year-old boy with silent sinus syndrome and associated ocular motility disorders. The association between silent sinus syndrome and ocular motility disturbance has been recently described in the literature. However, this is an infrequent association, mainly in childhood.

A síndrome do seio silencioso é uma afecção adquirida em que há colapso gradual do assoalho orbital e do seio maxilar (atelectasia do seio maxilar), o que pode acarretar alterações orbitárias e oculares associadas, como enoftalmia e hipotropia. Relatamos o caso de um paciente de 8 anos de idade com síndrome do seio silencioso e distúrbios da motilidade ocular. A associação entre a síndrome do seio silencioso e alterações da motilidade ocular extrínseca tem sido descrita na literatura. No entanto, esta é uma associação pouco frequente, principalmente na infância.

Biometric relationships of ocular components in esotropic amblyopia / Relações entre medidas ecobiométricas dos componentes oculares em ambliopia por esotropia

PURPOSE: To investigate the contribution of the individual ocular components, i.e. anterior chamber depth, lens thickness and vitreous chamber depth, to total axial length in patients with esotropic amblyopia. METHODS: The study population consisted of 74 children, aged between 5 and 8 years: thirty-seven patients with esotropic amblyopia and 37 healthy volunteers (control group). The participants underwent a comprehensive ophthalmological examination, including cycloplegic refraction and A-scan ultrasonography. Anterior chamber depth, lens thickness, vitreous chamber depth and total axial length were recorded. Paired Student's t-tests were used to compare biometric measurements between amblyopic eyes and their fellow eyes and between right and left eyes in the control group. To evaluate the contribution of the ocular components to the total axial length, we report the individual components as a percentage of total axial length. RESULTS: The comparison between amblyopic and fellow eyes regarding the individual contribution from ocular components to the total axial length revealed greater contribution from lens thickness (P=0.001) and smaller contribution from vitreous chamber depth (P=0.001) in amblyopic eyes, despite similar contribution from anterior chamber depth (P=0.434). The comparison between right and left eyes in the control group showed similar contributions from anterior chamber depth (P=0.620), lens thickness (P=0.721), and vitreous chamber depth (P=0.483). CONCLUSIONS: This study shows differences between amblyopic and non-amblyopic eyes when the total axial length is broken down into the individual contribution from the ocular components.

OBJETIVO: Investigar a contribuição individual da profundidade da câmara anterior, da espessura do cristalino e da profundidade da câmara vítrea para o comprimento axial total em pacientes com ambliopia por esotropia. MÉTODOS: Foram incluídas 74 crianças com idade entre 5 e 8 anos, sendo 37 pacientes com ambliopia por esotropia e 37 voluntários sadios (grupo controle). Foi realizado exame oftalmológico completo, incluindo refração sob cicloplegia e ultrassonografia modo A. Foram registrados profundidade da câmara anterior, espessura do cristalino, profundidade da câmara vítrea e comprimento axial total. A contribuição individual de cada componente para o comprimento axial total foi relatada como valor porcentual e teste t de Student pareado foi utilizado para a comparação entre olho amblíope e olho contralateral e entre olho direito e esquerdo no grupo controle. RESULTADOS: Olhos amblíopes, quando comparados aos olhos contralaterais, apresentaram maior contribuição da espessura do cristalino (P=0,001), menor contribuição da profundidade da câmara vítrea (P=0,001) e contribuição semelhante da profundidade da câmara anterior (P=0,434) para o comprimento axial total. A comparação entre olho direito e olho esquerdo no grupo controle mostrou contribuições semelhantes da profundidade da câmara anterior (p=0,620), da espessura do cristalino (P=0,721) e da profundidade da câmara vítrea (P=0,483) para o comprimento axial total. CONCLUSÕES: Este estudo mostrou diferenças entre olhos amblíopes e não amblíopes quando o comprimento axial total é dividido nas contribuições individuais dos seus componentes.

Amblyopia and Strabismus by Monocular Corneal Opacity Following Suspected Epidemic Keratoconjunctivitis in Infancy

PURPOSE: To identify the long term clinical course of amblyopia and strabismus that developed secondary to a monocular corneal opacity following suspected epidemic keratoconjunctivitis (EKC) in infancy. METHODS: This was a retrospective study analyzing the medical records of seven patients, treated in our clinic, who were followed for more than five years. RESULTS: Four patients in our clinic underwent a corneal ulcer treatment following suspected EKC. Each developed a monocular corneal opacity. Three patients with a chief complaint of corneal opacity were transferred to our clinic from other clinics. These patients had documented histories of treatment for EKC in infancy. All patients were treated with early occlusion therapy, but amblyopia persisted in four patients. Furthermore, all patients had strabismus and showed a significant reduction of stereoscopic vision. CONCLUSIONS: Although infants with EKC are not always cooperative, slit lamp examination should be performed as early as possible, and appropriate medical treatment should be performed, thus reducing the development of corneal opacity. Careful follow up should be regularly performed, and the occurrence of amblyopia or strabismus should be verified at an early stage using visual acuity or ocular alignment examination. Ophthalmologic treatments, including active occlusion therapy, should also be pursued.

Estrabismo horizontal: incidencia y su relación con la ambliopía como secuela sensorial / Horizontal strabismus: incidence and the relation with amblyopia as sensorial sequelae of it

Se realizó un estudio observacional descriptivo retrospectivo de los pacientes que fueron atendidos en la consulta de Oftalmología Pediátrica del Hospital Provincial General Docente Dr Antonio Luaces Iraola, con el diagnóstico de estrabismo horizontal durante el periodo de enero a julio del 2007, con la finalidad de determinar su incidencia y la relación con la ambliopía como secuela sensorial del mismo. La información se obtuvo a través de las hojas de cargo de la consulta y las historias clínicas de los pacientes con dicho diagnóstico, la información obtenida fue resumida en tablas y gráficos. Como resultados pudimos observar que el sexo femenino fue el más afectado, los estrabismos horizontales aparecieron con mayor frecuencia en los menores de ocho años, predominaron las esotropias sobre las exotropias, la mayor parte de pacientes ambliopes eran portadores de esotropias, el componente vertical fue muy frecuente en los pacientes.

A retrospective descriptive observational study of the patients who were seen in the Paediatric Ophthalmology office of the Provincial General Docent Hospital Antonio Luaces Iraola was carried out, with the diagnosis of horizontal strabismus during the period from January to July 2007, in order to determine its incidence and the relation with amblyopia as sensorial sequelae of it. The research data was obtained from the registries of the fhysician' office and clinical histories of the patients with this diagnosis, the obtained data was summarized in graphical tables and as a result it was observed that feminine sex was the most affected, the horizontal strabismus occurred most frequently in patients younger than eight year-old, esotropies were predominated over exotropies, most of amblyopic patients were carriers of esotropies, the vertical component was very frequent in patient.

Amblyopia after unilateral infantile cataract extraction after six weeks of age / Ambliopia no pós-operatório de catarata congênita unilateral operada após seis semanas de vida

PURPOSE: To determine interocular grating acuity difference in children treated for unilateral infantile cataract. METHODS: A group of 27 children previously treated for unilateral infantile cataract, had their monocular visual acuity measured by sweep visual evoked potentials. Interocular grating acuity difference was calculated as the absolute subtraction of monocular acuity scores. Lens status, opacity severity and eye alignment were considered for analysis. RESULTS: Mean interocular grating acuity difference obtained from unilateral cataract patients was 0.58 ± 0.20 logMAR. This result was significantly larger than 0.10 logMAR used as normative data. Children with severe opacities had a more pronounced amblyopia than the moderate ones. No significant correlation between amblyopia and strabismus or aphakia was found. CONCLUSIONS: Interocular acuity difference in this group of unilateral congenital cataract was more pronounced than previous reports, mainly because of delay in diagnosis, surgery and optical correction.

OBJETIVOS: Determinar a diferença interocular da acuidade visual de resolução de grades em crianças operadas de catarata congênita unilateral. MÉTODOS: Um grupo de 27 pacientes operados de catarata congênita unilateral tiveram mensurada sua acuidade visual monocular pelo potencial visual evocado de varredura. A diferença interocular foi calculada pela subtração absoluta das acuidades monoculares. A intensidade da opacificação, implante ou não de lente intraocular e presença de estrabismo foram consideradas para análise. RESULTADOS: A média da diferença interocular foi de 0,58 ± 0,20 logMAR. Esse resultado foi significantemente maior que 0,10 logMAR, valor considerado como média normal nos estudos normativos. Crianças com opacidades intensas tiveram ambliopia mais pronunciada que os casos moderados. Não houve correlação significante entre a intensidade da ambliopia com estrabismo e afacia. CONCLUSÕES: A diferença interocular nesse grupo de crianças operadas de catarata congênita unilateral foi muito mais pronunciada que artigos prévios, provavelmente pelos atrasos no diagnóstico, intervenção cirúrgica e correção óptica.

Evaluation of central, steady, maintained fixation grading for predicting inter-eye visual acuity difference to diagnose and treat amblyopia in strabismic patients.

Background: Diagnosis of amblyopia in preverbal strabismic patients is frequently made by binocular fixation preference (BFP) testing. The reports on reliability of BFP are equivocal. This study evaluated the reliability of BFP testing in patients with horizontal strabismus. Materials and Methods: This prospective observational study included patients with manifest, horizontal, comitant deviation >10 prism diopter (PD). Inter-eye acuity difference (IEAD) was calculated by converting Snellen visual acuity to logMAR and was compared with BFP testing. The fixation behavior of the non-preferred eye was evaluated by a single investigator as central or uncentral, steady or unsteady and maintained or unmaintained. Amblyopia was defined as the IEAD of >0.2 logMAR. Results: Of total 61 patients 36 were females and 36 had convergent squint, mean age 9.8 years. The correlation of BFP testing with IEAD was good for esotropia and exotropia. The sensitivity, specificity, positive and negative predictive value of central, steady, maintained (CSM) grading was 93%, 78%, 79%, and 93% respectively. Sensitivity and negative predictive values were higher in children aged four to nine years and anisometropia >1 diopter. The correlation between IEAD and lower grades of BFP testing was poor. Conclusions: CSM grading for BFP testing is useful for the detection of strabismic amblyopia but not useful to differentiate the depth of the amblyopia.

Results of amblyopia therapy in unilateral organic ocular abnormalities

To evaluate the visual results of amblyopic therapy in pediatric patients with monocular abnormalities. The hospital records of visually immature patients with unilateral organic ocular abnormalities and decreased visual acuity, who presented to the pediatric ophthalmology clinic over a one year period, were reviewed. Those who had 8 years old of age or less and underwent amblyopic treatment included in the study. Amblyopia was defined as visual acuity difference of more than 2 lines between the two eyes, absence of central fixation or fixation with inability to maintenance. Amblyopic treatment had been performed using full time occlusion method for one month and then reevaluation of the patient. Twenty patients [8 males and 12 females] with the mean age of 4 +/- 3.12 years [range: 1 to 8 years] were included in the study and were followed for a mean of 6 years [range: 2 to 8 years]. No patient was excluded from the study due to loss of follow-up. Among those who were able to read the chart [16 patients], the visual acuity increased from 3 meters counting fingers [range: 1 to 5 meters counting fingers] before treatment to 4/10 [range: 2/10 to 6/10] in last visit [P<0.01]. In 4 remaining eyes visual acuity increased from central to steady or steady and maintenance. A trial of full-time occlusion for visually immature patients with decreased visual acuity associated with unilateral organic ocular abnormalities specially traumatic or surgical injuries is recommended

Treatment options for non-compliant children with amblyopia in Kuwait

The mainstay treatment for more than 250 years has been occlusion of the better eye by an opaque patch. Pharmacological penalization is an alternative therapy for noncompliant child. The aim of this study is to investigate the effects of atropine penalization in amblyopic patients who are noncompliant with conventional occlusion. This is a retrospective study of 114 children aged 24 to 78 months with unilateral Ambyliopia diagnosed at the Pediatric Ophthalmology unit of AL-Bahar Eye Center in Kuwait during the time period December 1999 to august 2005 and fulfilling the inclusion criteria. The mean follow up time after starting amblyopia treatment was 38.4 +/- 27.12 months. All children with amblyopia were prescribed 6 hours occlusion per day. Children who are non compliant with occlusion were instructed to instil 1 drop of atropine 1% into the nonambyliopic once per day. A total of 114 patients participated in the study.72 [63.16%] patients were compliant with occlusion, 64 of them [88.9%] reached cure within mean time of 23.23 +/- 16.89 months. The remaining 42[36.84%] patients who are not compliant with occlusion were instructed to use atropine 1% eye drops once per day. 38 of them [90.5%] were compliant with penalization and 36 [94.7%] of them reached cure with a mean time 12.9 +/- 9.7 months. Conclusion: The result of this study suggests that atropine penalization should be considered as an alternative therapy in those who are noncompliant with occlusion in treatment of amblyopia

Reduction of Deviation Angle During Occlusion Therapy: In Partially Accommodative Esotropia with Moderate Amblyopia

PURPOSE: To evaluate changes in ocular alignment in partially accommodative esotropic children age ranged from 3 to 8 years during occlusion therapy for amblyopia. METHODS: Angle measurements of twenty-two partially accommodative esotropic patients with moderate amblyopia were evaluated before and at 2 years after occlusion therapy. RESULTS: Mean deviation angle with glasses at the start of occlusion treatment was 19.45+/-5.97 PD and decreased to 12.14+/-12.96 PD at 2 years after occlusion therapy (p<0.01). After occlusion therapy, 9 (41%) cases were indications of surgery for residual deviation but if we had planned surgery before occlusion treatment, 18 (82%) of patients would have had surgery. There was a statistical relationship between increase of visual acuity ratio and decrease of deviation angle (r=-0.479, p=0.024). CONCLUSIONS: There was a significant reduction of deviation angle of partially accommodative esotropic patients at 2 years after occlusion therapy. Our results suggest that occlusion therapy has an influence on ocular alignment in partially accommodative esotropic patients with amblyopia.

Causas de ambliopia e resultados do tratamento / Amblyopia: causes and treatment autcome

Objetivo: conhecer as causas de ambliopia em nosso meio, assim como a resposta obtida com o tratamento oclusivo empregado. Métodos: estudo retrospectivo, avaliando crianças amblíopes, com idade inferior a 12 anos, quanto ao sexo, causa da ambliopia,acuidade visual inicial e final, idade de início e o tempo necessário de tratamento oclusivo. Os resultados estão apresentados segundo a freqüência de ocorrência. Resultados:158 crianças compuseram a amostra, das quais 70,2% apresentavam esotropia, 13,2% exotropia, 0,7% hipertropia, 4,4% desvio horizontal associado à vertical e 11,4% eram ortofóricas; 6,6% apresentavam anisometropia, 0,7% catarata congênita e 6,6% outros diagnósticos. A acuidade visual de 85,5% das crianças melhorou, o que ocorreu mais rapidamente nas ortofóricas. O tempo de oclusão foi longo para todos os tipos de ambliopia. Conclusão: a causa mais freqüente de ambliopia foi a estrábica (esotropia)e o tratamento oclusivo foi efetivo para a maioria das crianças tratadas.

Objective: to evaluate the causes and the results of occlusion amblyopia treatment. Methods: a retrospectivestudy was done including children under 12 years old. Sex, age of starting treatment, etiology, ocular deviationaffection, visual acuity and time for the occlusion treatment were evaluated. Results: 158 children had all therequirements to compose the sample. 50.6% were males. 70.2% had esotropia, 13.2% exotropia, 0.7% hypertropia and 4.4% presented horizontal and vertical strabismus.11.4% had no ocular deviation. 6.6% presented anisometropia, 0.7% congenital cataract and 6.6% otherdiagnoses. Visual acuity improved in 85.5%, faster in the ortophoric children. The occlusion treatment time was longin all the deviation types. Conclusion: the treatment was beneficial in improving amblyopia in the majority of the children evaluated.

Ambliopia por estrabismo: estudo retrospectivo de pacientes em hospital universitário / Strabismic amblyopia: a retrospective study on patients from a university hospital

OBJETIVO: Avaliar a influência da adesão ao tratamento, da gravidade da ambliopia e da idade de início do tratamento em pacientes com ambliopia por estrabismo submetidos à terapia oclusiva. MÉTODOS: Analisaram-se 569 prontuários de pacientes com ambliopia por estrabismo atendidos no Hospital das Clínicas da Faculdade de Medicina da USP no período de 1983 a 2000. Os critérios de exclusão foram: perda de seguimento, idade maior que 12 anos, presença de nistagmo e outras doenças oculares. Todos foram submetidos a exame oftalmológico completo com avaliação da motilidade ocular, divididos por faixas etárias e classificados quanto ao tipo de estrabismo, gravidade da ambliopia e adesão ao tratamento. Os dados foram analisados estatisticamente pelo método de Fisher. RESULTADOS: Foram incluídos 198 pacientes (34,8 por cento). Não houve diferença de adesão nos diversos grupos etários. A taxa de sucesso foi maior nos pacientes com boa adesão independente da gravidade da ambliopia. Porém a adesão ao tratamento foi menor no grupo com ambliopia grave, que foi o mais freqüente e obteve menor taxa de sucesso em nossa amostra. Não houve relação entre idade e sucesso terapêutico. CONCLUSÕES: O estudo demonstrou que a adesão ao tratamento oclusivo desempenha papel fundamental na eficácia terapêutica. Com isto, idade de início do tratamento isoladamente não teve influência no sucesso terapêutico, uma vez que foi possível obter boa adesão a despeito da idade. Além disto, os resultados foram piores nos casos de ambliopia grave, nos quais a adesão foi menor.

Study of visual acuity and comparison of Snellen chart and retinoscopy in diagnosis of refractive errors

Refractive errors play important role in the etiology and treatment of strabismus and amblyopia. As screening is one of the common techniques in diagnosing visual disorders, children are, therefore, to be examined for the health of their vision at least once a year. This study is intended to compare the accuracy of Snellen chart and retinoscopy in diagnosis of refractive errors. The target population included guidance-school children in grade one from Sabzevar [2008 female and 2085 male subjects]. Relevant data were collected through interview and clinical examination. Visual acuity of the subjects was examined from a distance of 6m by Snellen chart and those with VA< 10/10 were examined with retinoscopy by an ophthalmologist. The mean visual acuity of both eyes in girls and boys obtained by the Snellen chart turned out to be 0.95 +/- 0.12 and 0.97 +/- 0.09 respectively. Also, 294 subjects appeared to be suffering from refractive errors. In 65% of the cases a significant difference was found between Snellen chart and retinoscopy in diagnosis of refractive errors [p<0.05]. Further research is suggested to reveal the possibility of differences of VA between girls and boys

Resultados do tratamento da ambliopia com levodopa combinada à oclusão / Results of amblyopia treatment with levodopa associated with occlusion therapy

OBJETIVO: Verificar a melhora da acuidade visual com levodopa/benzerazida combinada à oclusão parcial e seguida por oclusão total, em pacientes com ambliopia considerada irreversível. MÉTODOS: Realizou-se estudo experimental aberto, envolvendo 37 pacientes entre 7 e 40 anos de idade, com ambliopia por estrabismo ou anisometropia, durante 9 semanas. Todos os pacientes foram tratados com levodopa (0,70 mg/kg/dia) e benzerazida 25 por cento associada à oclusão de 4 horas/dia do olho dominante por 5 semanas e, nas 4 semanas seguintes foi realizada somente a oclusão total (24 h) do olho dominante. A acuidade visual foi medida na tabela do ETDR (Early Treatment Diabetic Retinopathy) com escala logMAR (logaritmo do mínimo ângulo de resolução) antes de iniciar o tratamento e após 1, 3, 5 e 9 semanas de tratamento. As adesões ao tratamento de oclusão e a ingesta do me-dicamento foram verificadas por meio de questionário e pela contagem das cápsulas. Os efeitos adversos foram avaliados por exame clínico e questionário. RESULTADOS: Após 9 semanas de tratamento, a acuidade visual média melhorou em logMAR de 0,58 ± 0,16 para 0,23 ± 0,16 (melhora de 4 linhas na tabela ETDR). CONCLUSAO: Levodopa, na dose de 0,70 mg/kg/dia, é bem tolerada e associada à oclusão produz melhora significativa na acuidade visual de pacientes com ambliopia considerada irreversível.