RESUMO Objetivo: Comparar a acuidade visual, sensibilidade ao contraste, estereopsia e desempenho visual subjetivo de présbitas usando lentes de contato Acuvue Oasys para presbiopia (AOP), Air Optix Aqua Multifocal (AOMF) e Air Optix Aqua Single Vision (AOSV). Método: Foi realizado estudo mascarado simples, cruzado. Vinte pacientes com presbiopia baixa (adição ≤+1,25 D) e 22 com presbiopia média/alta (adição ≥+1,50 D) usaram cada lente bilateralmente durante 1 hora, com descanso mínimo de uma noite entre as diferentes lentes. As medições incluíram acuidade visual para distância em alto e baixo contraste (HCVA, LCVA), sensibilidade ao contraste para distância (CS), HCVA para distância intermediária (70 cm) e para perto (50 cm e 40 cm), estereopsia e questionários subjetivos sobre nitidez visual, fantasmas, satisfação visão geral e conforto. As variáveis foram comparadas entre os tipos de lentes, utilizando medidas repetidas ANOVA. Resultados: As variáveis para distância (HCVA, LCVA, CS) foram significativamente piores com as multifocais em relação a AOSV (p≤0,008), exceto para AOMF no grupo de baixa adição, que não foi significativamente diferente (p>0,05). As multifocais foram significativamente melhores do que a AOSV para HCVA em 40 cm (p≤0,026). AOMF superou AOP para HCVA intermediária (p<0,03). AOP superou AOMF e AOSV em relação à estereopsia no grupo de presbiopia médio/alto (p≤0,03). Houve poucas diferenças significativas nas variáveis subjetivas, mas a satisfação visual global não foi significativamente diferente entre as lentes (p>0,05). A disposição para comprar lentes AOSV, AOMF e AOP foi: 20%, 40%, 50%, respectivamente, no grupo de presbiopia baixa; 14%, 32%, 23% no grupo de presbiopia média/alto, mas essas diferenças não foram estatisticamente significativas (p≥0,159). Conclusões: Melhorias futuras parecem ser necessárias para produção de uma lente multifocal que forneça aos présbitas uma vantagem significativa sobre a lente de visão única.

ABSTRACT Purpose: To compare visual acuity (VA), contrast sensitivity, stereopsis, and subjective visual performance of Acuvue® Oasys® for Presbyopia (AOP), Air Optix® Aqua Multifocal (AOMF), and Air Optix® Aqua Single Vision (AOSV) lenses in patients with presbyopia. Methods: A single-blinded crossover trial was conducted. Twenty patients with mild presbyopia (add ≤+1.25 D) and 22 with moderate/severe presbyopia (add ≥+1.50 D) who wore lenses bilaterally for 1 h, with a minimum overnight washout period between the use of each lens. Measurements included high- and low-contrast visual acuity (HCVA and LCVA, respectively) at a distance, contrast sensitivity (CS) at a distance, HCVA at intermediate (70 cm) and near (50 cm & 40 cm) distances, stereopsis, and subjective questionnaires regarding vision clarity, ghosting, overall vision satisfaction, and comfort. The test variables were compared among the lens types using repeated-measures ANOVA. Results: Distance variables (HCVA, LCVA, and CS) were significantly worse with multifocal lens than with AOSV lens (p≤0.008), except for AOMF lens in the mild presbyopia group in which no significant difference was observed (p>0.05). Multifocal lenses had significantly greater HCVA at 40 cm than AOSV lens (p≤0.026). AOMF lens had greater intermediate HCVA than AOP lens (p<0.03). AOP lens demonstrated greater improvements in stereopsis than AOMF and AOSV lens in the moderate/severe presbyopia group (p≤0.03). Few significant differences in subjective variables were observed, with no significant difference in the overall vision satisfaction observed between lens types (p>0.05). The proportions of patients willing to buy AOSV, AOMF, and AOP lenses were 20%, 40%, and 50%, respectively, in the mild presbyopia group and 14%, 32%, and 23%, respectively, in the moderate/severe presbyopia group; however, these differences were not statistically significant (p≥0.159). Conclusions: Further development of multifocal lenses is required before significant advantages of multifocal lenses over single vision lens are observed in patients with presbyopia.

OBJECTIVE: To estimate the global cost of establishing and operating the educational and refractive care facilities required to provide care to all individuals who currently have vision impairment resulting from uncorrected refractive error (URE). METHODS: The global cost of correcting URE was estimated using data on the population, the prevalence of URE and the number of existing refractive care practitioners in individual countries, the cost of establishing and operating educational programmes for practitioners and the cost of establishing and operating refractive care facilities. The assumptions made ensured that costs were not underestimated and an upper limit to the costs was derived using the most expensive extreme for each assumption. FINDINGS: There were an estimated 158 million cases of distance vision impairment and 544 million cases of near vision impairment caused by URE worldwide in 2007. Approximately 47 000 additional full-time functional clinical refractionists and 18 000 ophthalmic dispensers would be required to provide refractive care services for these individuals. The global cost of educating the additional personnel and of establishing, maintaining and operating the refractive care facilities needed was estimated to be around 20 000 million United States dollars (US$) and the upper-limit cost was US$ 28 000 million. The estimated loss in global gross domestic product due to distance vision impairment caused by URE was US$ 202 000 million annually. CONCLUSION: The cost of establishing and operating the educational and refractive care facilities required to deal with vision impairment resulting from URE was a small proportion of the global loss in productivity associated with that vision impairment.

OBJETIVO: Estimar el coste global del establecimiento y funcionamiento de las instalaciones educativas y de atención médica refractiva necesarias para proporcionar atención médica a todas las personas que padecen en la actualidad una discapacidad visual causada por un error de refracción no corregido (ERNC). MÉTODOS: El coste global de corregir los ERNC se calculó utilizando datos sobre la población, la prevalencia de ERNC y el número de especialistas en atención médica refractiva existentes en cada uno de los países, el coste del establecimiento y funcionamiento de programas educativos para especialistas y el coste del establecimiento y funcionamiento de las instalaciones de atención médica refractiva. Los supuestos aceptados garantizaron que no se subestimaran los costes y el límite máximo para los costes se obtuvo utilizando el extremo más caro para cada supuesto. RESULTADOS: Se calcularon 158 millones de casos de discapacidad en la visión de lejos y 544 millones de casos de discapacidad en la visión cercana causados por ERNC en 2007. Se necesitarían aproximadamente 47 000 refraccionistas clínicos funcionales adicionales a tiempo completo y 18 000 ópticos para proporcionar servicios de atención médica refractiva a esas personas. El coste global de formar al personal adicional y de establecer, mantener y administrar las instalaciones de atención médica refractiva necesarias se estimó en unos 20 000 millones de dólares estadounidenses (US$) y el coste límite superior se estimó en 28 000 millones de dólares estadounidenses. La pérdida estimada en el producto nacional bruto global debido a la discapacidad en la visión de lejos causada por ERNC fue de 202 000 millones de dólares estadounidenses anuales. CONCLUSIÓN: El coste del establecimiento y funcionamiento de las instalaciones de atención médica refractiva necesarias para tratar la discapacidad visual resultante de ERNC fue una pequeña proporción de la pérdida global en productividad asociada con esa discapacidad visual.

OBJECTIF: Estimation du coût global de mise en place et de fonctionnement des établissements de traitement de la réfraction et de formation nécessaires pour fournir des soins à toutes les personnes souffrant actuellement de troubles de la vision résultant d'une erreur de réfraction non corrigée. MÉTHODES: Le coût global de la correction des erreurs de réfraction a été estimé à l'aide des données sur la population, de la prévalence de la pathologie et du nombre de professionnels de la réfraction existant dans les différents pays, des coûts de mise en place et de fonctionnement des programmes éducatifs pour les praticiens et du coût de création et de gestion des établissements de soins pour la réfraction. Les hypothèses retenues veillaient à ce que les coûts ne soient pas sous-estimés et un seuil de coûts maximum a été calculé en utilisant les cas de figure les plus chers pour chaque hypothèse. RÉSULTATS: On a estimé à environ 158 millions le nombre de cas de déficience de la vision de loin et à 544 millions le nombre de cas de déficience de la vision de près due à un trouble de la réfraction dans le monde entier en 2007. Environ 47 000 nouveaux réfractionnistes cliniques en exercice à temps plein et 18 000 centres ophtalmiques seraient nécessaires pour fournir des services de soins de la réfraction à ces patients. Le coût global de formation du personnel supplémentaire et de mise en place, d'entretien et d'exploitation des installations de soins de réfraction nécessaires a été estimé à environ 20 milliards de dollars américains (US $) et le coût maximum était de 28 milliards US $. La perte estimée de produit intérieur brut mondial en raison de troubles de la vision de loin causés par la réfraction était de 202 milliards US $ par an. CONCLUSION: Le coût de mise en place et de fonctionnement des établissements de soins de la réfraction et de formation nécessaires pour faire face aux troubles de la vision résultant de pathologies de la réfraction représente une faible proportion de la perte globale de la productivité associée à cette déficience visuelle.