Clinical experience with adjustable scleral lenses / Experiência clínica com lentes esclerais ajustáveis

ABSTRACT Purpose: The aim of this study was to evaluate the fitting process of a scleral lens that allows several parameter adjustments during trials and after the initial period of use. In addition, we verified which adjustments were needed and used the most, their indications, and how often these resources were used, and checked the results. Methods: Scleral contact lens fittings in a private clinic setting were prospectively analyzed in a sequential, non-randomized, and non-comparative manner. All the patients underwent a complete ophthalmic examination and had an indication for scleral lens use (Zenlens, Alden Optical). Results: Scleral fit was analyzed in 80 eyes of 45 patients. Regarding diagnosis, 72% of the patients had keratoconus; 12%, radial keratotomy; 5%, post-refractive surgery ectasia; 5%, dry eye; and 3%, high myopia. In 66 (82.5%) of the 80 eyes studied, parameters were modified when the lenses were ordered. The reasons that led to the modifications were apical touch or decreased sagittal height, increased sagittal height, cylindrical over-refraction, poor visual acuity, lens flexure, peripheral touch, 360° edge compression, horizontal edge compression, and vertical edge compression. Conclusion: In this study, the use of Zenlens scleral lenses was shown to be a promising corrective treatment for patients requiring the use of scleral lenses. Although the study suggests a learning curve, as many adjustments were allowed, the lens could be customized according to the patients' needs. This increased the success rates of fitting and wearing, and consequently, use of the lens became a great option for the visual rehabilitation of patients.

RESUMO Objetivo: Avaliar o processo de adaptação de uma lente escleral que permite vários ajustes de parâmetros durante os testes e após o período inicial do seu uso; verificar quais os ajustes foram necessários, quais foram os mais utilizados, as suas indicações, a frequência com que estes recursos foram utilizados, e avaliar os resultados das mudanças realizadas. Métodos: A adaptação da lente de contato escleral foi analisada prospectivamente, de forma sequencial, não aleatória e não comparativa. Todos os pacientes foram submetidos a um exame oftalmológico completo e tinham indicação para o uso de lentes esclerais. Foi utilizada a lente Zenlens (Alden Optical). Resultados: Foi analisada a adaptação de lentes de contato esclerais em 80 olhos de 45 pacientes. Quanto ao diagnóstico, 72% tinham ceratocone, 12% tinham sido submetidos a ceratotomia radial, 5% tinham ectasia pós-cirurgia refrativa, 5% tinham olho seco, e 3%, alta miopia. Em 66 dos 80 olhos estudados (82,5%), os parâmetros foram modificados quando as lentes foram encomendadas. As razões foram: toque apical ou diminuição da altura sagital, aumento da altura sagital, sobre-refração cilíndrica, baixa acuidade visual, flexão da lente, toque periférico, compressão da borda em 360° e compressão da borda horizontal e/ou vertical. Conclusão: O uso de lentes esclerais Zenlens demonstrou ser uma forma de correção muito promissora para os pacientes que requerem o uso de lentes esclerais. Embora o estudo sugira uma curva de aprendizagem, é possível personalizar as lentes de acordo com as necessidades de cada pacientes. Este fato melhora a adaptação e aumenta a chance de sucesso do uso.

Clinical experience with adjustable scleral lenses.

PURPOSE: The aim of this study was to evaluate the fitting process of a scleral lens that allows several parameter adjustments during trials and after the initial period of use. In addition, we verified which adjustments were needed and used the most, their indications, and how often these resources were used, and checked the results. METHODS: Scleral contact lens fittings in a private clinic setting were prospectively analyzed in a sequential, non-randomized, and non-comparative manner. All the patients underwent a complete ophthalmic examination and had an indication for scleral lens use (Zenlens, Alden Optical). RESULTS: Scleral fit was analyzed in 80 eyes of 45 patients. Regarding diagnosis, 72% of the patients had keratoconus; 12%, radial keratotomy; 5%, post-refractive surgery ectasia; 5%, dry eye; and 3%, high myopia. In 66 (82.5%) of the 80 eyes studied, parameters were modified when the lenses were ordered. The reasons that led to the modifications were apical touch or decreased sagittal height, increased sagittal height, cylindrical over-refraction, poor visual acuity, lens flexure, peripheral touch, 360° edge compression, horizontal edge compression, and vertical edge compression. CONCLUSION: In this study, the use of Zenlens scleral lenses was shown to be a promising corrective treatment for patients requiring the use of scleral lenses. Although the study suggests a learning curve, as many adjustments were allowed, the lens could be customized according to the patients' needs. This increased the success rates of fitting and wearing, and consequently, use of the lens became a great option for the visual rehabilitation of patients.

Corneal Response to Scleral Contact Lens Wear in Keratoconus.

OBJECTIVE: To verify corneal alterations in patients with keratoconus who wear scleral contact lenses (ScCLs), focusing on corneal endothelial assessment. METHODS: Scleral contact lenses were fitted in 22 patients with keratoconus. During a 90-day follow-up, patients were assessed in three visits: at baseline, after 30 days, and after 90 days. Patients underwent visual acuity measurement, slitlamp biomicroscopy of the anterior segment, specular microscopy of the corneal endothelium, corneal pachymetry, measurement of the clearance between the cornea and the lens, and follow-up of ectasia. RESULTS: Variables related to endothelial morphology and pachymetry values did not change significantly over time. Central clearance measurements decreased in the 90-day period. No progression of corneal ectasia was observed, neither were infectious or inflammatory processes in the same period. CONCLUSION: Daily wear of ScCLs in patients with keratoconus was not associated with adverse effects on the cornea or endothelium over a period of 90 days nor was there evidence of disease progression. Central clearance values diminished over that period, but the significance of this observation remains unclear.

Global trends in myopia management attitudes and strategies in clinical practice - 2019 Update.

PURPOSE: A survey in 2015 identified a high level of eye care practitioner concern about myopia with a reported moderately high level of activity, but the vast majority still prescribed single vision interventions to young myopes. This research aimed to update these findings 4 years later. METHODS: A self-administrated, internet-based questionnaire was distributed in eight languages, through professional bodies to eye care practitioners globally. The questions examined: awareness of increasing myopia prevalence, perceived efficacy of available strategies and adoption levels of such strategies, and reasons for not adopting specific strategies. RESULTS: Of the 1336 respondents, concern was highest (9.0 ±â€¯1.6; p < 0.001) in Asia and lowest (7.6 ±â€¯2.2; p < 0.001) in Australasia. Practitioners from Asia also considered their clinical practice of myopia control to be the most active (7.7 ±â€¯2.3; p < 0.001), the North American practitioners being the least active (6.3 ±â€¯2.9; p < 0.001). Orthokeratology was perceived to be the most effective method of myopia control, followed by pharmaceutical approaches and approved myopia control soft contact lenses (p < 0.001). Although significant intra-regional differences existed, overall, most practitioners did not consider single-vision distance under-correction to be an effective strategy for attenuating myopia progression (79.6 %), but prescribed single vision spectacles or contact lenses as the primary mode of correction for myopic patients (63.6 ±â€¯21.8 %). The main justifications for their reluctance to prescribe alternatives to single vision refractive corrections were increased cost (20.6 %) and inadequate information (17.6 %). CONCLUSIONS: While practitioner concern about myopia and the reported level of activity have increased over the last 4 years, the vast majority of eye care clinicians still prescribe single vision interventions to young myopes. With recent global consensus evidence-based guidelines having been published, it is hoped that this will inform the practice of myopia management in future.

Descriptive analysis of the type and design of contact lenses fitted according to keratoconus severity and morphology.

PURPOSE: Keratoconus is characterized by bilateral asymmetrical corneal ectasia that leads to inferior stromal thinning and corneal protrusion. There is currently a lack of consensus regarding the most efficacious method for fitting contact lenses in patients with keratoconus, given the various topographical patterns and evolution grades observed in affected populations. The purpose of the present study was to evaluate the association between keratoconus evolution grade and topography pattern and the type and design of fitted contact lens. METHODS: We performed a retrospective analysis of contact lenses fitted in a total of 185 patients with keratoconus (325 eyes). Keratoconus was classified as either grade I, II, III, or IV based on keratometry and cone morphology (nipple, oval, globus, or indeterminate) results. RESULTS: A total of 325 eyes were evaluated in the present study. Of the 62 eyes classified as grade I, 66.1% were fitted with monocurve contact lenses. Of the 162 eyes classified as grade I and II, 51%, 30%, and 19% were fitted with adapted monocurve rigid gas-permeable contact lenses (RGPCL), bicurve lenses, and others lens types, respectively. Bicurve lenses were fitted in 52.1% and 62.2% of eyes classified as grade III and IV, respectively. Of the eyes classified as grade III and IV, monocurve and bicurve RGPCL were fitted in 26% and 55%, respectively. In eyes with oval keratoconus, 45%, 35%, and 20% were fitted with monocurve lenses, bicurve lenses, and other lens types, respectively. In eyes with round cones (nipple morphology), 55%, 30%, and 15% were fitted with bicurve lenses, monocurve lenses, and other lens types, respectively. CONCLUSION: Monocurve RGPCL were most frequently fitted in patients with mild to moderate keratoconus and oval cones morphology, while bicurve lenses were more frequently fitted in patients with severe and advanced keratoconus. This was probably because bicurve lenses are more appropriate for round cones due to increased corneal asphericity.

Descriptive analysis of the type and design of contact lenses fitted according to keratoconus severity and morphology / Análise descritiva dos tipos e parâmetros das lentes de contato adaptadas de acordo com o grau evolutivo e a morfologia do ceratocone

ABSTRACT Purpose: Keratoconus is characterized by bilateral asymmetrical corneal ectasia that leads to inferior stromal thinning and corneal protrusion. There is currently a lack of consensus regarding the most efficacious method for fitting contact lenses in patients with keratoconus, given the various topographical patterns and evolution grades observed in affected populations. The purpose of the present study was to evaluate the association between keratoconus evolution grade and topography pattern and the type and design of fitted contact lens. Methods: We performed a retrospective analysis of contact lenses fitted in a total of 185 patients with keratoconus (325 eyes). Keratoconus was classified as either grade I, II, III, or IV based on keratometry and cone morphology (nipple, oval, globus, or indeterminate) results. Results: A total of 325 eyes were evaluated in the present study. Of the 62 eyes classified as grade I, 66.1% were fitted with monocurve contact lenses. Of the 162 eyes classified as grade I and II, 51%, 30%, and 19% were fitted with adapted monocurve rigid gas-permeable contact lenses (RGPCL), bicurve lenses, and others lens types, respectively. Bicurve lenses were fitted in 52.1% and 62.2% of eyes classified as grade III and IV, respectively. Of the eyes classified as grade III and IV, monocurve and bicurve RGPCL were fitted in 26% and 55%, respectively. In eyes with oval keratoconus, 45%, 35%, and 20% were fitted with monocurve lenses, bicurve lenses, and other lens types, respectively. In eyes with round cones (nipple morphology), 55%, 30%, and 15% were fitted with bicurve lenses, monocurve lenses, and other lens types, respectively. Conclusion: Monocurve RGPCL were most frequently fitted in patients with mild to moderate keratoconus and oval cones morphology, while bicurve lenses were more frequently fitted in patients with severe and advanced keratoconus. This was probably because bicurve lenses are more appropriate for round cones due to increased corneal asphericity.

RESUMO Objetivo: O ceratocone é uma ectasia corneana bilateral e assimétrica que leva a afinamento corneano inferior e protrusão da córnea, não existe consenso sobre qual é o melhor caminho para adaptar lentes de contato em pacientes com ceratocone, considerando seus diferentes padrões topográficos e graus de evolução. O objetivo desse estudo é associar o grau de evolução e padrão topográfico com o tipo/desenho da lente adaptada. Métodos: Análise retrospectiva das lentes de contato adaptadas em 185 pacientes com ceratocone (325 olhos) no Departamento de Lentes de Contato. O ceratocone foi classificado de acordo com a ceratometria em graus I, II, III e IV e de acordo com a morfologia em cone redondo, oval, globoso e indeterminado. Resultados: Foram avaliados 325 olhos. Em 66,1% dos olhos com grau I foi adaptada lente monocurva. Dos 162 olhos classificados como graus I e II foram adaptadas lentes monocurva em 51%, bicurva em 30% e outros em 19%. Em relação aos olhos grau III, em 52,1% foram adaptadas lentes bicurvas e o mesmo aconteceu em 62,2% dos olhos com grau IV. Apenas 26% dos olhos grau III ou IV receberam lentes monocurva, com necessidade de bicurvas em 55%. 45% dos cones ovais foram adaptados com lentes monocurva, 35% com bicurvas e 20% com outros tipos, enquanto 55% dos cones redondos foram adaptados com lentes bicurvas, apenas 30% com monocurvas e 15% com outros desenhos. Conclusão: Lentes de contato rígida gás-permeável (LCRGP) monocurvas são mais frequentemente utilizadas em ceratocones leves e moderados e em ovais, enquanto bicurvas são mais usadas para casos graves e avançados e em cones redondos.

Global trends in myopia management attitudes and strategies in clinical practice.

PURPOSE: Myopia is a global public health issue; however, no information exists as to how potential myopia retardation strategies are being adopted globally. METHODS: A self-administrated, internet-based questionnaire was distributed in six languages, through professional bodies to eye care practitioners globally. The questions examined: awareness of increasing myopia prevalence, perceived efficacy and adoption of available strategies, and reasons for not adopting specific strategies. RESULTS: Of the 971 respondents, concern was higher (median 9/10) in Asia than in any other continent (7/10, p<0.001) and they considered themselves more active in implementing myopia control strategies (8/10) than Australasia and Europe (7/10), with North (4/10) and South America (5/10) being least proactive (p<0.001). Orthokeratology was perceived to be the most effective method of myopia control, followed by increased time outdoors and pharmaceutical approaches, with under-correction and single vision spectacles felt to be the least effective (p<0.05). Although significant intra-regional differences existed, overall most practitioners 67.5 (±37.8)% prescribed single vision spectacles or contact lenses as the primary mode of correction for myopic patients. The main justifications for their reluctance to prescribe alternatives to single vision refractive corrections were increased cost (35.6%), inadequate information (33.3%) and the unpredictability of outcomes (28.2%). CONCLUSIONS: Regardless of practitioners' awareness of the efficacy of myopia control techniques, the vast majority still prescribe single vision interventions to young myopes. In view of the increasing prevalence of myopia and existing evidence for interventions to slow myopia progression, clear guidelines for myopia management need to be established.

Contact lens fitting in a patient with Alport syndrome and posterior polymorphous corneal dystrophy: a case report.

Alport Syndrome is a hereditary disease that is caused by a gene mutation and affects the production of collagen in basement membranes; this condition causes hemorrhagic nephritis associated with deafness and ocular changes. The X-linked form of this disease is the most common and mainly affects males. Typical ocular findings are dot-and-fleck retinopathy, anterior lenticonus, and posterior polymorphous corneal dystrophy. Some cases involving polymorphous corneal dystrophy and corneal ectasia have been previously described. Here we present a case report of a 33-year-old female with Alport syndrome, posterior polymorphous corneal dystrophy, and irregular astigmatism, whose visual acuity improved with a rigid gas permeable contact lens.

Contact lens fitting in a patient with Alport syndrome and posterior polymorphous corneal dystrophy: a case report / Adaptação de lentes de contato em paciente com síndrome de Alport e distrofia polimorfa posterior: relato de caso

ABSTRACT Alport Syndrome is a hereditary disease that is caused by a gene mutation and affects the production of collagen in basement membranes; this condition causes hemorrhagic nephritis associated with deafness and ocular changes. The X-linked form of this disease is the most common and mainly affects males. Typical ocular findings are dot-and-fleck retinopathy, anterior lenticonus, and posterior polymorphous corneal dystrophy. Some cases involving polymorphous corneal dystrophy and corneal ectasia have been previously described. Here we present a case report of a 33-year-old female with Alport syndrome, posterior polymorphous corneal dystrophy, and irregular astigmatism, whose visual acuity improved with a rigid gas permeable contact lens.

RESUMO A síndrome de Alport é descrita como uma doença hereditária que afeta um gene relacionado à produção de colágeno das membranas basais causando nefrite hemorrágica associada com surdez e alterações oculares. A forma ligada ao X é a mais comum e afeta principalmente homens. Os achados oculares típicos são retinopatia em ponto-mancha, lenticone anterior e distrofia polimorfa posterior. Alguns casos foram descritos de associação entre a distrofia polimorfa posterior e ectasia corneana. Nós apresentamos um caso de paciente do sexo feminino, 33 anos, diagnóstico de síndrome de Alport, distrofia polimorfa posterior e astigmatismo irregular, que apresenta melhora da acuidade visual após adaptação com lentes de contato rígidas gás permeáveis.

The use of ocular anatomical measurements using a rotating Scheimpflug camera to assist in the Esclera® scleral contact lens fitting process.

PURPOSE: To test for associations between Pentacam(®) derived topography variables and to evaluate the predictive power of those variables in relation to scleral contact lens (SCL) fit. SETTING: Department of Ophthalmology and Visual Sciences, Federal University of São Paulo, São Paulo-SP, Brazil. DESIGN: Prospective observational non-randomised, non-comparative study. METHODS: Forty-seven patients (63 eyes) were indicated for the use of Esclera(®) SCL. All patients underwent Scheimpflug imaging before the initial SCL evaluation. The following parameters were measured by Pentacam: corneal elevations, thickness, density, and anterior chamber depth (ACD). Correlations between the SCL parameters and the Pentacam measurements were analysed with Pearson's correlation coefficients. A simple linear regression model was created for each lens parameter using the most-correlated Pentacam variable. RESULTS: In the total group, the results show correlations between the SCL parameters and the corneal astigmatism, ACD and pentacam-measured corneal height (Hm), with p<0.001 each. In addition, an inverse correlation between the lens sagittal depth (LSD) and the anterior radii minimum was shown (p<0.001). In the keratoconus group, the results show correlations between the SCL parameters and ACD and Hm (p<0.001, each). An inverse correlation between the LSD and the total thickness corneal density average was also observed (p=0.003). CONCLUSION: There was a positive correlation between the LSD and ACD, even as LD and ACD in the keratoconus group. Thus, these results suggest that certain Pentacam measurements can be good predictors of the most appropriate Esclera lens to be fitted in keratoconus patients.

A randomized clinical comparison of OPTI-FREE EXPRESS and ReNu MultiPLUS multipurpose lens care solutions.

OBJECTIVE: To evaluate subjective symptoms and clinical signs of tolerability and comfort in silicone and non-silicone hydrogel contact lens (CL) wearers using two different multipurpose solution (MPS) CL care regimens. METHODS: This was a randomized, double-masked, contralateral, crossover, multicenter (n=9) study. One hundred and eleven subjects were enrolled in the study, and were randomly assigned either silicone hydrogel CLs or non-silicone hydrogel CLs. Before wear, the CLs were randomly conditioned for at least 10 hours in a multipurpose disinfection solution (MPDS) preserved with either: Regimen 1-polyquaternium-1 0.001% and myristamidopropyl dimethylamine 0.0005% (POLYQUAD and ALDOX, respectively; OPTIFREE EXPRESS MPDS, Alcon Laboratories, Inc., Fort Worth, TX, USA); or Regimen 2-multipurpose solution preserved with polyhexamethylene biguanide 0.0001% (PHMB, ReNu MultiPLUS MPS, Bausch & Lomb, Rochester, NY, USA). The study had two in-office visits, 1 week apart. Subjects wore assigned CLs for approximately 4 hours at each visit. At each visit, subjects' eyes were examined before CL insertion and at 2 hours and 4 hours after insertion. Corneal staining type and area, conjunctival staining, conjunctival injection, subjective symptoms (tolerability), and comfort were evaluated. RESULTS: One hundred and five subjects (210 eyes) completed the study. The total corneal staining score of area and type were statistically significantly less in Regimen 1 than in Regimen 2 (P<0.000001). The area of conjunctival staining was statistically significantly less in Regimen 1 than in Regimen 2 (P=0.03). No clinically significant hyperemia was observed for either regimen. Both tolerability (P=0.02) and patient preference (P=0.05) were in favor of Regimen 1. CONCLUSIONS: Statistically significant clinical differences were evident between the two CL care regimens when used with silicone and non-silicone hydrogel CLs. OPTI-FREE EXPRESS MPDS users showed less corneal and conjunctival staining and reported greater comfort and tolerability to the CL/solution combination than ReNu MultiPLUS MPS users.

Sistemas atuais de cuidados e manutenção de lentes de contato: [revisão] / Current care and maintenance systems for contact lenses: [review]

A correta manutenção das lentes de contato é fundamental para se obter sucesso e manter a continuidade de seu uso. É grande o número de pacientes que abandonam o uso de suas lentes por problemas que poderiam ser solucionados com tratamentos relativamente simples ou com uma orientação mais adequada. O mau uso das lentes, associado à má adaptação, contaminação, doenças oculares prévias e fatores ambientais, podem aumentar o número de infecções corneanas através da proliferação de microorganismos. O presente artigo visa apresentar as atualizações em relação aos cuidados e manutenção com as lentes de contato.

The proper maintenance of contact lenses is crucial for their success and to maintain the continuity of their use. Many patients abandon the use of their lenses due to problems that could be solved with relatively simple treatments. The misuse of lenses, coupled with poor adjustment, contamination, eye disease and environmental factors may increase the number of corneal infections through the proliferation of microorganisms. This article aims to provide contact lens care and maintenance updates.

Desempenho visual de lentes de contato gelatinosas de diferentes tipos baseado na análise de frentes de onda / Optical performance of different soft contact lenses based on wavefront analysis

OBJETIVOS: Avaliar e comparar o desempenho visual, por meio da análise de frentes de onda, de seis diferentes tipos de lentes de contato gelatinosas [Cooperflex® (Coopervision), Frequency® 55 Aspheric (Coopervision), World Vision FW® (World Vision), Pure Vision® (Bausch & Lomb), Focus® Monthly (Ciba Vision), Focus® Choice AB (Ciba Vision)]. MÉTODOS: Realizou-se estudo prospectivo em amostra constituída por 130 olhos de 71 indivíduos portadores de miopia ou hipermetropia até 6,00D e astigmatismo até 1,50D, com acuidade visual corrigida com óculos igual ou superior a 20/20. Os sujeitos foram inicialmente submetidos ao exame clínico oftalmológico e posteriormente, ao exame de análise de frentes de onda com o aberrômetro LADARWave® (Alcon), em duas condições: sem correção óptica e em uso de um dos tipos de lente de contato incluídos no estudo, com grau correspondente ao equivalente esférico do paciente e corrigido pela distância vértice. Para análise de resultados os indivíduos foram divididos em seis grupos similares, sendo testado em cada grupo um dos tipos de lente incluídos no estudo. RESULTADOS: Mudanças nos valores das aberrações de alta ordem foram verificadas durante uso das lentes de contato. De 130 olhos estudados, 78 apresentaram aumento no valor de RMS total durante o uso da lente. Os seis tipos de lente estudados demonstraram tendência ao aumento no valor médio de RMS total durante seu uso, sem diferença estatisticamente significante entre as mesmas. O estudo demonstrou tendência ao aumento no valor médio das aberrações tipo "coma" durante o uso das lentes. As lentes Frequency® Aspheric e Cooperflex® apresentaram melhor desempenho visual em relação ao "coma". O estudo demonstrou tendência à diminuição no valor médio das aberrações esféricas durante o uso das lentes, sendo esta tendência maior nos pacientes míopes em relação aos hipermétropes. Foi demonstrado tendência ao aumento no valor médio de outras aberrações de alta ordem...

PURPOSE: To evaluate the visual performance by wavefront analyses of six different kinds of soft contact lenses: Cooperflex® (Cooper Vision), Frequency® 55 Aspheric (Cooper Vision), World Vision FW® (World Vision), Pure Vision® (Bausch & Lomb), Focus® Monthly (Ciba Vision) and Focus® Choice AB (Ciba Vision). METHODS: A prospective study was performed with 130 eyes of 71 myopic or hyperopic patients with astigmatism until 1.50 diopter and best corrected visual acuity 20/20 or better. The patients first underwent ophthalmic examination and then wavefront analyses without visual correction and wearing one of the different contact lenses included in the study. The patients were divided into six similar groups, each one tested with one of the six lenses included in the study. RESULTS: Changes at the values of high order aberrations were verified during the use of contact lenses. In 78 (60 percent) of the 130 analyzed eyes an increase at the RMS (rooth mean square) values during the use of contact lens was detected. All types of analyzed contact lenses showed an increase of "coma" aberrations due to contact lens use. Frequency® Aspheric and Cooperflex® had the best visual performance in relation to "coma". There was a decrease in the medium value of spherical aberrations during the use of contact lenses, higher in myopic patients than in the hyperopic. There was an increase in the other high order aberrations (that exclude the third order "coma" and fourth order spherical aberration) characterized by the component "others" on the aberrometry examination. Focus® Choice AB had the best visual performance of this component. CONCLUSION: The use of soft contact lenses modifies the performance of high order aberrations, showing an increase of the medium values of asymmetric Zernike aberrations. This was not observed for symmetric spherical aberrations. No statistically significant differences were observed between the performance of six kinds of...

Prevalence and causes of visual impairment in low-middle income school children in Sao Paulo, Brazil.

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.

[Contact lens in children: epidemiological aspects]. / Lente de contato em crianças: aspectos epidemiológicos.

PURPOSE: To describe the epidemiology of children submitted to contact lens fit. METHODS: Retrospective study of 73 children that had been submitted to contact lens fit at the "Universidade Federal de São Paulo". This study analyzed sex distribution, age, diagnosis, indications and contact lens fitted at first examination. RESULTS: 34 children (46.6%) were male and 39 (53.4%) female, aged between 2 and 12 years with mean of 10.2 and standard deviation of 2.42. The most common diagnosis was aphakia, in 16 (21.9%) cases. Keratoconus was present in 14 (19.1%), leucoma in 11 (15%), anisometropia in 10 (13.7%), refractive errors in 9 (12.3%), irregular astigmatism in 7 (9.5%), ectopia lentis in 4 (5.4%), high myopia in one case (1.3%) and one child (1.3%) had no ocular pathology, just wishing to change eye color. 52 (71.2%) had medical indication, 9 (12.3%) had optical indication and 12 (16.4%) had cosmetic indication. Contact lenses were fitted in 103 eyes, the most tested lens was rigid gas permeable in 43 (41.7%), soft lens in 41 (39.8%) and cosmetic soft lens in 11 (10.6%). CONCLUSION: Aphakia was the most common diagnosis among children in use of contact lens. The incidence of medical indication was higher than the others and the most tested lens was the rigid gas permeable one.

Lente de contato em crianças: aspectos epidemiológicos / Contact lens in children: epidemiological aspects

OBJETIVO: Traçar o perfil epidemiológico de crianças encaminhadas para adaptação de lente de contato. MÉTODOS: Foi realizado estudo retrospectivo de pacientes registrados no Setor de lente de contato da Universidade Federal de São Paulo. Os pacientes com até 12 anos de idade foram avaliados quanto ao sexo, idade, diagnóstico, indicação e tipo de lente de contato testada na primeira consulta. RESULTADOS: Dos 73 prontuários avaliados, 34 (46,6 por cento) pertenciam a crianças do sexo masculino e 39 (53,4 por cento) a crianças do sexo feminino. A idade variou de 2 a 12 com média de 10,2 e desvio-padrão de 2,42 anos. O diagnóstico mais encontrado foi afacia em 16 (21,9 por cento) crianças, seguido de ceratocone em 14 (19,1 por cento), leucoma em 11 (15 por cento), anisometropia em 10 (13,7 por cento), ametropia em 9 (12,3 por cento), astigmatismo irregular em 7 (9,5 por cento) e ectopia lentis em 4 (5,4 por cento). Uma criança era alta míope (1,3 por cento) e outra emétrope (1,3 por cento) que possuía desejo de usar lente de contato estética. Em relação às indicações, 52 (71,2 por cento) pacientes tinham indicação médica, 9 (12,3 por cento) indicação óptica e 12 (16,4 por cento) indicação cosmética. Foram testadas lentes em 103 olhos sendo as mais testadas a rígida gás permeável esférica em 43 (41,7 por cento), a gelatinosa esférica em 41 (39,8 por cento) e a gelatinosa cosmética em 11 (10,6 por cento). CONCLUSÃO: O perfil epidemiológico dos usuários de lente de contato nessa faixa etária tem como diagnóstico mais prevalente a afacia, a indicação mais freqüente a de ordem médica e a lente mais testada a rígida gás permeável esférica.

PURPOSE: To describe the epidemiology of children submitted to contact lens fit. METHODS: Retrospective study of 73 children that had been submitted to contact lens fit at the "Universidade Federal de São Paulo". This study analyzed sex distribution, age, diagnosis, indications and contact lens fitted at first examination. RESULTS: 34 children (46.6 percent) were male and 39 (53.4 percent) female, aged between 2 and 12 years with mean of 10.2 and standard deviation of 2.42. The most common diagnosis was aphakia, in 16 (21.9 percent) cases. Keratoconus was present in 14 (19.1 percent), leucoma in 11 (15 percent), anisometropia in 10 (13.7 percent), refractive errors in 9 (12.3 percent), irregular astigmatism in 7 (9.5 percent), ectopia lentis in 4 (5.4 percent), high myopia in one case (1.3 percent) and one child (1.3 percent) had no ocular pathology, just wishing to change eye color. 52 (71.2 percent) had medical indication, 9 (12.3 percent) had optical indication and 12 (16.4 percent) had cosmetic indication. Contact lenses were fitted in 103 eyes, the most tested lens was rigid gas permeable in 43 (41.7 percent), soft lens in 41 (39.8 percent) and cosmetic soft lens in 11 (10.6 percent). CONCLUSION: Aphakia was the most common diagnosis among children in use of contact lens. The incidence of medical indication was higher than the others and the most tested lens was the rigid gas permeable one.

Long-term follow-up of orthokeratology corneal reshaping using wavefront aberrometry and contrast sensitivity.

PURPOSE: To evaluate changes in ocular wavefront aberrations and contrast sensitivity during 1-year follow-up of overnight orthokeratology. METHODS: Prospective study of 26 eyes that underwent orthokeratology with the BE lens design. Wavefront measurements were analyzed at baseline and after 1, 8, 30, 90, 180, and 365 nights of orthokeratology for a 6.5-mm pupil diameter. Contrast sensitivity 1 year after orthokeratology was compared to the baseline value under photopic conditions and mesopic conditions, with and without glare, in the spatial frequencies of 1.5, 3, 6, 12, and 18 cycles/degree. A P value of less than 0.05 was statistically significant. RESULTS: Higher-order aberration root-mean-square (HOA-RMS) increased statistically significantly from 0.41 +/- 0.12 microm to 1.04 +/- 0.32 microm up to night 8. Defocus (Z4) decreased until night 8 and then stabilized. Astigmatism (Z3 + Z5) did not change. There was a sevenfold increase in spherical aberration (Z12) until night 8, which subsequently remained unchanged (P<0.001). Coma (Z7 + Z8) increased until night 90 and then stabilized (P<0.001). Other Zernike modes showed stability at night 1, with the exception of quadrafoil (Z14) (P=0.048). Mesopic contrast sensitivity, with and without glare, at 18 cycles/degree, decreased but failed to reach statistical significance (P=0.922 and P=0.827, respectively). CONCLUSIONS: Most optical aberrations stabilized within the first week after beginning orthokeratology with BE lens. There was not a statistically significant reduction in contrast sensitivity 1 year after treatment.

[Optical performance of different soft contact lenses based on wavefront analysis]. / Desempenho visual de lentes de contato gelatinosas de diferentes tipos baseado na análise de frentes de onda.

PURPOSE: To evaluate the visual performance by wavefront analyses of six different kinds of soft contact lenses: Cooperflex (Cooper Vision), Frequency(R) 55 Aspheric (Cooper Vision), World Vision FW (World Vision), Pure Vision (Bausch & Lomb), Focus Monthly (Ciba Vision) and Focus Choice AB (Ciba Vision). METHODS: A prospective study was performed with 130 eyes of 71 myopic or hyperopic patients with astigmatism until 1.50 diopter and best corrected visual acuity 20/20 or better. The patients first underwent ophthalmic examination and then wavefront analyses without visual correction and wearing one of the different contact lenses included in the study. The patients were divided into six similar groups, each one tested with one of the six lenses included in the study. RESULTS: Changes at the values of high order aberrations were verified during the use of contact lenses. In 78 (60%) of the 130 analyzed eyes an increase at the RMS (rooth mean square) values during the use of contact lens was detected. All types of analyzed contact lenses showed an increase of 'coma' aberrations due to contact lens use. Frequency Aspheric and Cooperflex had the best visual performance in relation to 'coma'. There was a decrease in the medium value of spherical aberrations during the use of contact lenses, higher in myopic patients than in the hyperopic. There was an increase in the other high order aberrations (that exclude the third order 'coma' and fourth order spherical aberration) characterized by the component 'others' on the aberrometry examination. Focus Choice AB had the best visual performance of this component. CONCLUSION: The use of soft contact lenses modifies the performance of high order aberrations, showing an increase of the medium values of asymmetric Zernike aberrations. This was not observed for symmetric spherical aberrations. No statistically significant differences were observed between the performance of six kinds of lenses included at this study.

[Current care and maintenance systems for contact lenses]. / Sistemas atuais de cuidados e manutenção de lentes de contato.

The proper maintenance of contact lenses is crucial for their success and to maintain the continuity of their use. Many patients abandon the use of their lenses due to problems that could be solved with relatively simple treatments. The misuse of lenses, coupled with poor adjustment, contamination, eye disease and environmental factors may increase the number of corneal infections through the proliferation of microorganisms. This article aims to provide contact lens care and maintenance updates.

Stability of wavefront aberrations during the daytime after 6 months of overnight orthokeratology corneal reshaping.

PURPOSE: To evaluate the stability of wavefront aberrations during the daytime after 6 months of overnight orthokeratology corneal reshaping. METHODS: A prospective study of 26 eyes using the Ultravision BE lens design during 6 months of overnight wear. Uncorrected visual acuity (UCVA), cycloplegic refraction, and wavefront aberrometry were measured at 8 AM (within 1 hour after awakening and removing lenses), 1 PM (5 to 6 hours after lens removal), and 6 PM (10 to 12 hours after lens removal). RESULTS: There was no significant difference in UCVA between 8 AM, 1 PM, and 6 PM (P=.383). Spherical power from wavefront aberrometry showed significant regression from 8 AM to 1 PM (P<.001) and stabilized near zero diopters. Total root-mean-square (RMS) increased and higher order aberration RMS and defocus (Z4) decreased between 8 AM and 1 PM (P<.001) but did not change for the rest of the day (P>.001). There was no statistically significant change in astigmatism (Z3 and Z5) (P=.449) and coma (Z7 and Z8) (P=.145) between 8 AM, 1 PM, and 6 PM. Spherical aberration (Z12) showed regression throughout the day (P<.001). CONCLUSIONS: After 6 months of overnight orthokeratology wear, some optical aberrations showed regression during the day. Despite no significant change in UCVA during 10 to 12 hours, there was a significant increase in defocus (Z4) within the first 5 hours after removing the orthokeratology lens and a decrease in spherical aberration (Z12) throughout the day.