Effects of a new-generation hybrid contact lens on visual performance and vision-related quality of life in patients with keratoconus / Os efeitos de uma lente de contato híbrida de nova geração no desempenho visual e na qualidade de vida relacionada à visão em pacientes com ceratocone

ABSTRACT Purpose: The aim of this study was to evaluate the efficacy of a new-generation hybrid contact lens for improving visual outcomes and vision-related quality-of-life performance in patients with keratoconus who had intolerance or treatment failure of conventional correction methods such as the use of soft silicone-hydrogel or rigid gas-permeable contact lenses. Methods: Twenty-eight patients with keratoconus (42 eyes) were enrolled in this prospective cross-sectional study. Airflex (Swisslens) lenses were fitted in the patients' eyes in accordance with the manufacturer's instruction. Ophthalmologic examinations, including manifest refraction, best-corrected distance visual acuity, slit-lamp biomicroscopy, and National Eye Institute Visual Function Questionnaire 25 (NEI-VFQ-25) assessment, were performed at baseline and the 6-month visit. Results: An adequate fit was achieved in 39 eyes (92.9%) of 26 patients. Six eyes of 3 patients were excluded from the study owing to discontinuation of lens wearing. The mean age of the successful wearers was 20.3 ± 4.9 years. The mean best-corrected distance visual acuity was statistically significantly improved from 0.62 ± 0.30 to 0.11 ± 0.06 logMAR with the Airflex hybrid contact lenses (p<0.001). The mean overall composite NEI-VFQ-25 score statistically significantly increased with the Airflex hybrid contact lenses at the 6-month visit as compared with that at baseline (from 77.1 ± 16.3 to 90.9 ± 7.3, p=0.036). Statistically significantly better scores were obtained with the Airflex hybrid contact lenses in all the NEI-VFQ-25 subscale items (all p<0.05). No significant adverse effects were observed. Conclusions: New-generation hybrid contact lenses can be used as an effective alternative for correction of irregular astigmatism in patients with keratoconus who have intolerance or treatment failure of conventional methods. Significant improvement in vision-related quality-of-life in patients with keratoconus can be achieved with these lenses.

RESUMO Objetivo: Este estudo tem como objetivo avaliar a eficácia de lentes de contato híbridas de nova geração nos resultados visuais e na qualidade de vida relacionada à visão em pacientes com ceratocone com intolerância ou insucesso dos métodos de correção habituais, tais como lentes flexíveis de silicone-hidrogel ou rígidas permeáveis a gases. Métodos: Foram incluídos neste estudo transversal prospectivo 42 olhos de 28 pacientes com ceratocone. Uma lente Airflex (Swisslens) foi aplicada nos olhos de acordo com as instruções do fabricante. Um exame oftalmológico, incluindo refração manifesta, melhor acuidade visual corrigida para longe, biomicroscopia com lâmpada de fenda e a aplicação do National Eye Institute Visual Function Questionnaire-25 (NEI-VFQ-25), foi realizado no início do estudo e na visita de 6 meses. Resultados: Foi possível obter um ajuste adequado em 39 olhos (92,9%) de 26 pacientes. Foram excluídos do estudo 6 olhos de 3 pacientes devido à cessação do uso de lentes. A idade média dos usuários bem-sucedidos era de 20,3 ± 4,9 anos. A média da melhor acuidade visual corrigida para longe foi melhorada estatisticamente de 0,62 ± 0,30 para 0,11 ± 0,06 logMAR com as lentes de contato híbridas Airflex (p<0,001). A pontuação média geral composta no questionário NEI-VFQ-25 aumentou de forma estatisticamente significativa com a lente de contato híbrida Airflex na visita de 6 meses, em comparação com a pontuação inicial (de 77,1 ± 16,3 para 90,9 ± 7,3, p=0,036). As lentes de contato híbridas Airflex apresentaram pontuações melhores com significância estatística em todos os itens das sub-escalas do NEI-VFQ-25 (todos com p<0,05). Nenhum efeito adverso significativo foi observado. Conclusões: Lentes de contato híbridas de nova ge ração podem ser usadas como uma alternativa eficaz para a correção do astigmatismo irregular em pacientes com ceratocone com intolerância ou insucesso dos métodos habituais. Com essas lentes, pode-se alcançar uma melhora significativa na qualidade de vida relacionada à visão em pacientes com ceratocone.

El ecosistema microbiano conjuntival: Condiciones ambientales del trópico y tolerancia de las lentes de contacto / The conjunctival microbial ecosystem: Tropical environmental conditions and contact lens tolerance

Los defectos refractivos son considerados la segunda causa de discapacidad visual a nivel mundial. Los trastornos de la visión como la miopía se pueden corregir mediante cirugía refractiva, anteojos o lentes de contacto. Se plantea que los cambios en el microbioma ocular provocados por el uso de lentes de contacto están relacionados con el desarrollo de complicaciones e infecciónes. La microbiota ocular puede variar según las condiciones estacionales, la temperatura, la edad, sexo y la exposición ambiental. Se expone el presente estudio para evaluar si la microbiota de los usuarios de lentes de contacto difería de la de quienes no los usaban, según diversos factores. Se realizó un estudio descriptivo, no experimental, transversal, en Ambato, Ecuador. La población de estudio estuvo conformada por participantes con edades entre 18 y 59 años. Se cuantificó la diversidad bacteriana por medio de la amplificación del genoma completo, del cual se secuenció la región V3 del gen 16S rRNA de 40 muestras en la plataforma secuenciadora. Se descubrió que el microbioma conjuntival de los usuarios de lentes de contacto no era significativamente diferente del de los NULC y no detectó un aumento significativo de microorganismos patógenos. Los principales taxones bacterianos fueron similares entre los grupos, aunque la abundancia de cada taxón varió dentro de cada grupo. Este tipo de estudios es fundamental para el éxito de la terapia ocular y el manejo de los microorganismos diana de la terapia antimicrobiana(AU)

Refractive errors are considered the second cause of visual impairment worldwide. Vision disorders such as nearsightedness can be corrected by refractive surgery, glasses, or contact lenses. It is proposed that the changes in the ocular microbiome caused by the use of contact lenses are related to the development of complications and infections. The ocular microbiota can vary according to seasonal conditions, temperature, age, gender and environmental exposure. The present study is set out to assess whether the microbiota of contact lens wearers differed from that of non-wearers, based on various factors. A descriptive, non-experimental, cross-sectional study was carried out from November 2021 to March 2022 in Ambato, Ecuador. The study population consisted of participants aged between 18 and 59 years. Bacterial diversity was quantified by amplification of the complete genome, from which the V3 region of the 16S rRNA gene of 40 samples was sequenced on the sequencing platform. The conjunctival microbiome of contact lens wearers was found to be not significantly different from the ones of NULCs and did not detect a significant increase in pathogenic microorganisms. The main bacterial taxa were similar between groups although the abundance of each taxon varied within each group. This type of study is essential for the success of ocular therapy and the management of the target microorganisms of antimicrobial therapy(AU)

Age-based estimation of contact lens base curve in Filipino infants

@#<p style="text-align: justify;"><strong>Objective.</strong> To create an age-based formula to estimate the base curve needed for contact lens fitting using measured central corneal curvature (CCC) with a handheld auto keratometer from ophthalmologically normal infants.</p><p style="text-align: justify;"><strong>Methods.</strong> This is a prospective cross-sectional study involving 70 ophthalmologically normal full-term infants aged 0 to 12 months. The infants were divided into four groups: 0-3 months, >3-6 months, >6-9 months and >9-12 months. CCC was measured with a handheld auto keratometer and was used to compute for the base curve. Differences in CCC between the four groups were measured and linear regression models were used for formula creation.</p><p style="text-align: justify;"><strong>Results.</strong> The mean CCC was highest in group 1 at 45.5 ±2.4 diopters (D). These values slowly decreased as age increased. A formula predictive of the base curve based on the infants age was derived using linear regression analysis. It predicted that for every month increase in age, there is a 0.063 millimeter increase in the base curve (p<0.001).</p><p style="text-align: justify;"><strong>Conclusion.</strong> Infant CCC is highest at birth and gradually decreases as age increases. The formula can predict the base curve needed for contact lens fitting in infants without the need for a handheld autokeratometer.</p>

Contact corneal thermal burn from domestic electric clothes iron in a female teenager: A case report

Corneal thermal burn from domestic electric clothes pressing iron is a very rare occurrence among teenagers in Nigeria. We report the case of thermal burn to the ocular surface of a 16-year-old female, at home, from the sole plate of an electric clothes pressing iron. She presented with superficial eyelids and corneal burns (RoperHall Classification Grade II; Dua Classification Grade II). The patient was successfully managed with topical cyclopentolate 2%, topical moxifloxacin 0.5%, and tetracycline ointment. Well-documented causative agents of domestic eye injuries in the young in Nigeria are usually flying missiles. Thermal ocular injuries are quite uncommon, and when they occur, are likely due to steam burns. This report highlights the electric clothes pressing iron as a domestic hazard that caregivers must be mindful of.

Molecular identification of antibiotic-resistant bacteria isolated from used contact lens cases

Aims@#The contact lens (CL) has become one of the most convenience refractive devices used in vision correction, occupational and in cosmetics purposes. Despite the convenience of CL usage, poor hygiene might cause eye infections due to microbial contamination. In this work, a random collection of used CL cases among Universiti Malaysia Terengganu (UMT) students had shown the emergence of antibiotic-resistant bacteria towards commonly used antibiotics to treat eye infections.@*Methodology and results@#The study was carried out from 28 CL cases samples with the duration of one to three months of use. Bacteria that were successfully isolated from the CL cases were then exposed to the commonly prescribed antibiotics followed by identification through the partial 16S rDNA sequencing. Our finding exhibited that the rate of contamination is over 50% where 32 bacteria were isolated, with 20 (62.5%) of the isolates were Gram-positive bacteria. Approximately 31% of the isolated bacteria are resistant and intermediate resistant to the commonly used antibiotics to treat eye infection, especially erythromycin and chloramphenicol. The isolated bacteria were genotypic identified as Bacillus cereus, B. anthracis, Acinetobacter variabilis, Klebsiella pneumoniae, and Serratia marcescens. These bacteria are known as a common cause for microbial keratitis, except for A. variabilis, where the association of this bacteria in causing microbial keratitis is relatively rare.@*Conclusion, significance and impact of study@#This study highlights the emergence of antibiotic-resistant bacteria that can cause severe eye infections among CL wearer. The high percentage of contamination (>50%) found from the isolates reflected on the lack of hygiene practice on the CL handling. Thus, it is crucial to perceive this study as microbial contamination will lead to more serious eye infection disease such as conjunctivitis and keratitis.

Detección de Acanthamoeba por reacción en cadena de la polimerasa en tiempo real en líquidos de conservación de lentes de contacto / Detection of Acanthamoeba sp. by real-time polymerase chain reaction in contact lens solutions

RESUMEN Objetivo: Estandarizar una técnica de reacción en cadena de la polimerasa en tiempo real para la detección del parásito e identificar Acanthamoeba en líquidos conservantes de lentes de contacto. Métodos: Se realizó un estudio descriptivo observacional de corte transversal sobre la técnica de reacción en cadena de la polimerasa en tiempo real para la detección de Acanthamoeba, en el Instituto de Investigaciones en Ciencias de la Salud de la ciudad de Asunción, en Paraguay. Se analizaron 110 líquidos conservantes aportados por usuarios sanos de lentes de contacto, mediante reacción en cadena de la polimerasa en tiempo real y cultivo en medio PAGE - SDS. Resultados: Se estandarizó con éxito la técnica de reacción en cadena de la polimerasa en tiempo real con límite de sensibilidad de 1 pg/µL. Se aisló Acanthamoeba a partir de una muestra (1 por ciento) por método de cultivo, mientras que la carga parasitaria en el líquido conservante fue inferior al límite de detección de la reacción en cadena de la polimerasa en tiempo real. El ADN obtenido del cultivo de dicha muestra fue positivo para Acanthamoeba por este método. Conclusión: El sistema estandarizado presenta buena sensibilidad y podrá ser incorporado en los laboratorios que cuentan con acceso a equipos de reacción en cadena de la polimerasa en tiempo real para un diagnóstico rápido y más eficiente en casos de sospechas de queratitis amebiana. Recomendamos el uso combinado de métodos moleculares y cultivo para aumentar la potencia del diagnóstico, sobre todo en muestras donde la carga parasitaria es muy baja(AU)

ABSTRACT Objective: Standardize a real-time polymerase chain reaction technique for detection of the parasite and identify Acanthamoeba in contact lens solutions. Methods: A cross-sectional observational descriptive study was conducted about a real-time polymerase chain reaction technique for detection of Acanthamoeba at the Institute of Health Sciences Research in the city of Asunción, Paraguay. A total 110 solutions were analyzed, which were provided by healthy contact lens users, by real-time polymerase chain reaction and culture in SDS-PAGE medium. Results: Successful standardization was achieved of the real-time polymerase chain reaction technique with a sensitivity limit of 1 pg/µl. Acanthamoeba was isolated from one sample (1 percent) by culture, whereas the parasite load in the contact lens solution was below the detection limit of the real-time polymerase chain reaction technique. The DNA obtained from the culture of that sample was positive for Acanthamoeba by the real-time polymerase chain reaction technique method. Conclusion: The system standardized exhibits good sensitivity and may be incorporated into laboratories with real-time polymerase chain reaction technique equipment for a rapid and more efficient diagnosis of suspected amoebic keratitis. We recommend the combined use of molecular methods and culture to enhance diagnostic power, mainly in samples where the parasite load is very low(AU)

Reabilitação visual com lentes de contato após transplante de córnea / Visual reabilitation with contact lenses after corneal keratoplasty

Resumo A adaptação de lentes de contato após o transplante de córnea tem sido considerada um desafio na reabilitação visual. Atualmente existe a possibilidade de adaptação de lentes de contato de vários tamanhos, diversos desenhos e com diferentes espessuras e materiais, como por exemplo lentes gelatinosas, lentes corneanas rígidas gás-permeáveis, lentes córneo-esclerais, mini esclerais e esclerais. O objetivo deste estudo foi apresentar uma revisão da literatura atual que possa exemplificar a utilização de alguns dos diferentes tipos de lentes de contato que possam ser usadas após o transplante de córnea. Foi realizada uma revisão integrativa da literatura médica na língua inglesa, utilizando como base de dados para a pesquisa, Pubmed e Mendeley. Como critério de inclusão, foi estabelecido a relevância do artigo de acordo com a experiência da equipe. Foram selecionados 26 artigos, com ano de publicação entre 2001 e 2018. Dentre os artigos selecionados, cinco possuem como principal assunto o transplante de córnea, nove artigos sobre lentes de contato em geral, e 12 artigos sobre lentes de contato esclerais ou mini esclerais. Devido a maior transmissibilidade de oxigênio para a córnea, o uso das lentes corneanas rígidas gás-permeáveis mostrou-se mais seguro e com probabilidade de uso por um período maior de tempo.

Abstract Contact lens fitting after corneal transplantation has been considered a challenge in visual rehabilitation. There is currently the possibility of adapting contact lenses of various sizes, various designs and with different thicknesses and materials, such as gelatinous lenses, gas-permeable rigid corneal lenses, corneal-scleral lenses, mini-scleral and scleral lenses. The objective of this study was to present a review of current literature that may exemplify the use of some of the different types of contact lenses that can be used after corneal transplantation. An integrative review of the medical literature in the English language, using as a database for the research, Pubmed and Mendeley. Twenty six articles were selected, with year of publication between 2001 and 2018, as inclusion criterion, the relevance of articles according to the authors' experience was used. Five articles were selected that have as main subject corneal transplantation, nine articles on contact lenses in general, and 12 articles on scleral or mini scleral contact lenses. Due to the greater transmissibility of oxygen to the cornea, the use of rigid gas-permeable corneal lenses was shown to be safer and more likely to be used for a longer period of time.

Clinical Perceptions and Practice Patterns for Amblyopia in Korea

PURPOSE: We used a questionnaire to explore perceptions and clinical practice patterns of Korean pediatric ophthalmologists in terms of amblyopia.METHODS: From September to November 2018, we conducted a web-based questionnaire survey of 99 specialists of the Korean Association for Pediatric Ophthalmology and Strabismus who operated ophthalmology clinics in Korea. We received 56 responses (56.57%) and retrospectively analyzed the data.RESULTS: The average specialist age was 44.0 ± 9.7 years. The mean age of treated amblyopia patients was 3 to 5 years (69.6%); the most common amblyopia was refractive anisometropic amblyopia (75.0%). On average, treatment commenced at 4 years of age (53.6%); child and parent co-operation most significantly influenced treatment success (46.4%). The preferred test was cycloplegic refraction (96.4%) and the preferred treatment occlusion therapy (100%) with glasses correction (98.2%). Occlusion therapy was most commonly performed for 2 hours/day (69.6%); the minimum age for eyeglasses prescription was 2.10 ± 1.18 years. Only three respondents (5.36%) prescribed contact lenses and only one (1.79%) performed refractive surgery.CONCLUSIONS: In Korea, amblyopia treatment is based on occlusion therapy and glasses correction. However, the time of treatment commencement, the duration of occlusion therapy, and the glasses used for correction varied. It is necessary to develop guidelines for amblyopia treatment; these should reflect current medical conditions.

Situación del diagnóstico de Queratitis Amebiana en Paraguay / Status of the diagnosis of Amebic Keratitis in Paraguay

Las amebas de vida libre (AVL) existen ampliamente distribuidas en la naturaleza, donde el género Acanthamoeba es la más frecuentemente aislada en diversos ambientes del suelo, aire y agua y está asociada a enfermedades en humanos. Su capacidad para vivir en ambientes adversos se debe a su baja demanda de alimentación y a que en su ciclo biológico tiene un estadio en forma de quiste, lo que la hace muy resistente. El hombre, como hospedero puede desarrollar infecciones en el sistema nervioso central, en la piel y los pulmones. A nivel ocular es capaz de afectar la córnea y producir queratitis. Por lo tanto es considerado un importante agente etiológico de patologías humanas. En esta revisión se aborda la biología, patogénesis y los mecanismos de defensa del ser humano frente a la infección por Acanthamoeba. Además a esto, de los factores de riesgo por el uso de lentes de contacto y malos hábitos de higiene del usuario y por último el abordaje diagnóstico microbiológico y molecular. Esta herramienta ha ido mejorando con el avance de la tecnología, indispensable para la temprana identificación y el logro de una oportuna y eficaz intervención clínica y terapéutica. Finalmente exponemos la situación actual en relación a los métodos de diagnóstico con que se cuentan y los escasos reportes clínicos existentes en Paraguay. Palabras clave: Acanthamoeba sp., Lentes de contacto, Queratitis.

Free-living amoeba (FLA) exist widely in nature, where the genus Acanthamoeba is the most frequently isolated in various environments of soil, air and water. It is associated with diseases in human. Its ability to live in adverse environments is due to the low food demand and that in its biological cycle it has a cyst-shaped stage, which makes it very resistant. Man, as a host, can acquire infections in the central nervous system and in the skin and lungs. On the ocular level, it can affect the cornea and cause keratitis. Therefore, it is considered an important etiological agent of human pathologies. This review addresses the biology, pathogenesis and human defense mechanisms against Acanthamoeba infection. In addition to this, the review explores the risk factors related to the use of contact lenses and poor hygienic behavior of the users, and finally the microbiological and molecular diagnosis. This particular tool has been improved with the advancement of technology and is essential for timely identification and the achievement of a good clinical and therapeutic intervention. Finally, we present the current situation in Paraguay regarding the few existing clinical reports and the diagnostic methods available. Key words: Acanthamoeba sp., Contact lenses, Keratitis.

Características de los pacientes pediátricos con miopía por encima de 6 dioptrías / Characteristics of pediatric patients with greater than 6 diopter myopia

RESUMEN Objetivo: Identificar las características de los pacientes pediátricos con miopías por encima de 6 dioptrías. Métodos: Se realizó un estudio descriptivo y observacional, de corte longitudinal, en 43 niños entre 3 y 15 años de edad con diagnóstico de miopía igual o mayor de 6 dioptrías en uno o ambos ojos (72 ojos), quienes acudieron a la consulta del Servicio de Oftalmología Pediátrica y Estrabismo del Instituto Cubano de Oftalmología "Ramón Pando Ferrer" durante el periodo comprendido entre enero y diciembre del año 2018. Las variables del estudio fueron la edad, el sexo, el color de la piel, la miopía (isometrópica y anisometrópica), la longitud axial, la agudeza visual con corrección, el tipo de corrección óptica, la presencia y el grado de estereopsia. Resultados: Predominó el grupo de 3 a 5 años (34,4 por ciento), el sexo femenino y el color de la piel blanca. La longitud axial aumentó junto con el equivalente esférico de los pacientes. La corrección más usada correspondió a los cristales, aunque se demostró estadísticamente que con los lentes de gas permeables los pacientes presentaban mejor agudeza visual (p= 0,016), donde se registró también la media más alta de equivalente esférico. De 43 pacientes, 20 (46,5 por ciento) no presentaron estereopsia. Los pacientes con anisometropías (64 por ciento) no presentaron estereopsia, lo que fue estadísticamente significativo. Conclusiones: Con los lentes de gas permeables los pacientes presentan mejor agudeza visual y mayor equivalente esférico. La mayor cantidad de pacientes sin estereopsia corresponde a las miopías por anisometropías(AU)

ABSTRACT Objective: Identify the characteristics of pediatric patients with greater than 6 diopter myopia. Methods: An observational descriptive longitudinal study was conducted of 43 children aged 3-15 years diagnosed with myopia equal to or greater than 6 diopters in one or both eyes (72 eyes) who attended the Pediatric Ophthalmology and Strabismus Service at Ramón Pando Ferrer Cuban Institute of Ophthalmology from January to December 2018. The variables considered were age, sex, skin color, myopia (isometropic or anisometropic), axial length, corrected visual acuity, type of optical correction, and presence and degree of stereopsis. Results: A predominance was found of the 3-5 years age group (34.4 percent), female sex and white skin color. Axial length increased with spherical equivalent. The most common correction was glasses, but it was statistically demonstrated that gas permeable lenses provided better visual acuity (p= 0.016) and the highest spherical equivalent mean. Of the 43 patients evaluated, 20 (46.5 percent) did not present stereopsis. Patients with anisometropia (64 percent) did not present stereopsis, which constituted a statistically significant fact. Conclusion: Gas permeable lenses provide better visual acuity and a greater spherical equivalent. Most of the patients without stereopsis have anisometropic myopia(AU)

Rehabilitación del sector anterior con carillas de porcelana lentes de contacto, guiado por planificación digital. Informe de un caso / Front sector rehabilitation with porcelain contact lens venners guided by digital planning. Case report

Resumen Los pacientes acuden cada vez más, al consultorio odontológico a fin de mejorar el aspecto de su sonrisa, ampliando la demanda de procedimientos estéticos, y es responsabilidad del odontólogo ofrecer distintas técnicas para que el paciente acoja un tratamiento óptimo, orientado a la conservación de los tejidos dentales en este aspecto; las carillas de cerámica sin preparación, o lentes de contacto, constituyen una opción conservadora de recubrimiento parcial, que mejora la estética del sector anterior, el siguiente caso describe una posibilidad restauradora estética mínimamente invasiva para la rehabilitación del sector anterior, con el uso de porcelana IPS e. max® Press, resaltando el proceso de planificación por medio del diseño digital en dos dimensiones.

Abstract Patients increasingly come to the dental office to improve the appearance of their smile, expanding the demand for aesthetic procedures, and it is the dentist´s responsibility to offer different techniques for the patient to receive an optimal treatment, aimed at preserving the dental tissues in this aspect, unprepared ceramic veneers, or contact lenses, are a conservative alternative, which improves the aesthetics of the front sector, the following case describes a minimally invasive aesthetic restorative alternative for the rehabilitation of the anterior sector, with the use of IPS e. max® Press porcelain, highlighting the planning process through digital design in two dimensions.

Parasitosis ocular por Acanthamoeba / Acanthamoeba parasitic eye infection

RESUMEN El parasitismo es uno de los fenómenos más sorprendentes de los observados en los animales. El número de organismos conocidos de vida parasitaria es muy elevado. Existe una gran cantidad de especies cuya supervivencia está relacionada con la de otras y dependen, en distinta medida, de ellas. Esta dependencia no implica que los animales parásitos sean organismos degenerados o deficientes; al contrario, a la vida parasitaria se ha llegado tras largo tiempo de evolución, en el que los parásitos han ido superando barreras y adaptándose a vivir en, o sobre sus hospedadores. Las queratitis por Acanthamoeba son infrecuentes; pero se describe un aumento a nivel mundial relacionado con el uso creciente de lentes de contacto. El diagnóstico precoz y el tratamiento adecuado deben realizarse para evitar la pérdida de la visión. Se realizó una búsqueda de artículos publicados, con el objetivo de conocer sobre la Acanthamoeba como parásito y su afectación ocular. Se utilizó la plataforma Infomed, específicamente la Biblioteca Virtual de Salud(AU)

ABSTRACT Parasitism is one of the most surprising phenomena among those occurring in animals. The number of known parasitic organisms is very high. There is a large number of species whose survival is related to that of others and depend on them to a greater or lesser degree. Such dependence does not imply that parasitic animals are either degenerate or deficient. On the contrary, parasitic life has been the result of a long process of evolution along which parasites have gradually overcome hurdles and have adapted to live in or on their hosts. Acanthamoeba keratitis is a rare disease, but a worldwide increase has been reported due to the growing use of contact lenses. Early diagnosis and appropriate treatment are required to prevent sight loss. A search was conducted for published papers with the purpose of learning about Acanthamoeba as a parasite and the related eye conditions. Use was made of the platform Infomed, specifically the Virtual Health Library(AU)

La queratitis, y el desafío de encontrarse en medio del camino / Keratitis and the challenge of being in the middle of the road

La córnea es un órgano transparente e inmunológicamente privilegiado, debido a la falta de vasos sanguíneos, distribución y acomodación de sus fibras de colágeno. Sus ingeniosos métodos de defensa incluyen barreras físicas como el epitelio corneal, el recambio y composición de la película lágrima, y finalmente, la protección recibida del medio ambiente por medio del párpado. La córnea tiene 5 capas, incluyendo un epitelio de 5 a 7 células de espesor, estroma y endotelio, con capas de apoyo entre el estroma y las otras dos capas. A la infección de la córnea secundaria a bacterias, hongos, ó protozoarios se le conoce como queratitis1, una afección que amenaza a la visión y que puede llegar a perforación corneal o a una extensión de la infección como la endoftalmitis. De hecho, la complicación más seria de la queratitis es la ceguera producida por cicatrización corneal(AU)

Degeneración esferoidea. Reporte de caso / Spheroidal degeneration. Case report

RESUMEN Se reportó el caso clínico de una fémina de 50 años de edad. Acudió a los Servicios de Oftalmología, del Hospital Provincial Comandante Faustino Pérez Hernández, de Matanzas. Refirió síntomas irritativos y disminución visual por el ojo izquierdo. El examen oftalmológico mostró en dicho ojo la presencia de lesiones esferoideas de color ámbar, conjuntivo corneales en periferia (horas 3-4 y 9). Se extendían en banda a la córnea central, algunas con aspecto nodular. En el ojo derecho presentaba lesiones similares pero localizadas mayoritariamente en la periferia corneal y conjuntiva horas 3 y 9. Con estos elementos se estableció diagnóstico clínico de degeneración esferoidea, enfermedad degenerativa corneal poco frecuente y generalmente asintomática siempre que no progrese y afecte la visión. Se aplicó como tratamiento una queratectomia superficial, manual, con colocación de una lente de contacto terapéutica en el ojo izquierdo, sin complicaciones. Hubo regresión de los síntomas irritativos y mejoría de la agudeza visual constatada en las consultas de seguimiento. Se recomendó la necesidad de protección solar al constituir las radiaciones ultravioletas un factor de riesgo de importancia en el desarrollo de esta enfermedad.

ABSTRACT The authors reported the case of a woman, aged 50 years, who assisted the Ophthalmology service of the Provincial Hospital "Comandante Faustino Pérez Hernández", of Matanzas. She referred irritant symptoms and left eye visual decrease. The ophthalmologic examination showed the presence of amber-color spheroidal lesions, corneal conjunctives in periphery (3-4 and 9 hours) in that eye. They extended in bands to the central cornea, some of them with nodular aspect. There were similar lesions in the right eye, but they were located mainly corneal and peripheral conjunctive hours 3 and 9. With these elements it was established the clinical diagnosis of spheroidal degeneration, a few frequent corneal degenerative disease that is almost always asymptomatic if it does not progress and affects sight. As a treatment the patient underwent a manual, superficial keratectomy with location of therapeutic contact lens without complications. There it was a regression of the irritant symptoms and an improvement of the visual acuity stated in the follow-up consultations. The patients was recommended sun protection because ultraviolet rays are important risk factors in the development of this disease.

Irlen syndrome: systematic review and level of evidence analysis / Síndrome de Irlen: revisão sistemática e análise do nível de evidência

ABSTRACT Background: Scotopic sensitivity syndrome, later called Meares-Irlen syndrome or simply Irlen syndrome (IS) has been described as symptoms of poor reading ability due to poor color matching and distorted graphic images. Individuals with this syndrome are considered slow, ineffective readers with low comprehension and visual fatigue. It is still uncertain whether the disease pathophysiology is an independent entity or part of the dyslexia spectrum. Nevertheless, treatments with lenses and colored filters have been proposed to alleviate the effect of the luminous contrast and improve patients' reading performance. However, no evidence of treatment effectiveness has been achieved. Objective: The aim of the present study was to obtain evidence about IS etiology, diagnosis and intervention efficacy. Methods: A systematic review was performed covering the available studies on IS, assessing the available data according to their level of evidence, focusing on diagnostic tools, proposed interventions and related outcomes. Results: The data showed high heterogeneity among studies, and lack of evidence on the existence of IS and treatment effectiveness. Conclusion: The syndrome as described, as well as its treatments, require further strong evidence.

RESUMO Background: A síndrome da sensibilidade escotópica, posteriormente denominada síndrome de Meares-Irlen ou simplesmente síndrome de Irlen (SI), foi descrita como indivíduos com sintomas de baixa capacidade de leitura devido à combinação de cores e distorções nas imagens. Indivíduos com essa síndrome podem apresentar leitura lenta e ineficaz, com baixo nível de compreensão e fadiga visual. A fisiopatologia da doença ainda é incerta como uma entidade independente ou como parte do espectro da dislexia. No entanto, tratamentos com lentes e filtros coloridos foram propostos com o objetivo de aliviar o efeito do contraste luminoso e melhorar o desempenho de leitura dos pacientes. Outrossim, nenhuma evidência de eficácia do tratamento foi alcançada. Objetivos: Obter evidências sobre a etiologia, eficácia diagnóstica e intervenção da SI. Métodos: Foi realizada uma revisão sistemática, cobrindo os estudos disponíveis sobre a SI, avaliando os dados disponíveis de acordo com seu nível de evidência, com foco em ferramentas de diagnóstico, intervenções propostas e desfechos relacionados. Resultados: Os dados mostram alta heterogeneidade, falta de evidência sobre a existência da SI e eficácia do tratamento. Conclusões: A síndrome descrita e seus tratamentos exigem evidências mais robustas.

Effect of contact lenses on ocular biometric measurements based on swept-source optical coherence tomography / Efeito de lentes de contato em um biômetro ocular baseado na tomografia de coerência óptica de varredura

ABSTRACT Purpose: To determine the reliability of swept- source optical coherence tomography in cases in which soft contact lenses cannot be removed when acquiring biometric measurements. Methods: Eight subjects were included and only one eye per participant was analyzed. Each eye was measured six times by swept-source optical coherence tomography with the IOLMaster 700 instrument (Carl Zeiss Meditec, Jena, Germany). Axial length, central corneal thickness, anterior chamber depth, lens thickness, and keratometric measurements were evaluated for the naked eye and while wearing soft contact lenses of three different powers (-1.5, -3.0, and +2.0 D). Results: There were statistically significant changes in axial length, central corneal thickness, anterior chamber depth, and keratometric measurements with soft contact lenses as compared to the naked eye (p<0.001). However, there were no significant differences in lens thickness outcomes between the naked eye and while wearing the three soft contact lenses (p>0.5). The changes in axial length, central corneal thickness, and anterior chamber depth were lens-specific and dependent on the thickness of the lens used. Conclusions: Sept-source optical coherence tomography based lens thickness measurements while wearing soft contact lenses are comparable to those of the naked eye. However, the thickness and the optical design of the soft contact lens may lead to significant differences in the axial lengh, central corneal thickness, anterior chamber deph, and keratometric measurements.

RESUMO Objetivo: Determinar a confiabilidade da tomografia de coerência óptica de varredura em casos especiais em que lentes de contato gelatinosas não podem ser removidas ao realizar medições biométricas. Métodos: Oito indivíduos foram incluídos e apenas um olho por participante foi analisado. Cada olho foi medido seis vezes por tomografia de coerência óptica de varredura com o instrumento IOLMaster 700 (Carl Zeiss Meditec, Jena, Alemanha). O comprimento axial, a espessura central da córnea, a profundidade da câmara anterior, a espessura da lente e as medidas ceratométricas foram avaliados a olho nu e enquanto usavam lentes de contato gelatinosas de três diferentes potências (-1,5, -3,0 e +2,0 D). Resultados: Houve alterações significativas no comprimento axial, espessura central da córnea, profundidade da câmara anterior e medidas ceratométricas com as lentes de contato gelatinosas em comparação com as a olho nu (p<0,001). No entanto, não houve diferenças significativas nos resultados de espessura do cristalino entre o olho nu e enquanto usava as três lentes de contato gelatinosas (p>0,5). As alterações de comprimento axial, espessura central da córnea e profundidade da câmara anterior foram específicas da lente e dependentes da espessura da lente usada. Conclusões: As medições da espessura da lente baseadas na tomografia de coerência óptica da Sept-source, enquanto usam lentes de lentes de contato gelatinosas, são comparáveis às do olho nu. Entretanto, a es pessura e o desenho óptico da lente de contato gelatinosa podem levar a diferenças significativas no comprimento axial, na espessura central da córnea, na profundidade da câmara anterior e nas medidas ceratométricas.

Lentes de contato provocando conjuntivite por Ralstonia Pichettii / Contact lenses causing conjunctivity by Ralstonia Pichettii

Resumo O presente relato apresenta o caso de conjuntivite causada por Ralstonia pichettii em paciente imunocompetente usuária de lente de contato. A bactéria isolada da solução utilizada para desinfecção das lentes R. pichettii não pertente a microbiota humana mas infecta pacientes imunodeprimidos e está presente em soluções aquosas. Não há padronização de sensibilidade para esta bactéria e poucos antibióticos foram testados para bactérias não fermentadoras da glicose. Devido ao reduzido perfil de sensibilidade aos antimicrobianos demonstrado pela R. pichettii, torna-se importante a identificação correta deste agente etiológico em quadros de conjuntivite e ceratites. Este relato de caso ilustra que R. Pickettii é um patógeno mais importante do que se pensava anteriormente.

Abstract The present report reports a case of conjunctivitis caused by Ralstonia pichettii in an immunocompetent patient wearing a contact lens. The bacterium isolated from the solution used to disinfect R. pichettii does not belong to the human microbiota but infects immunodepressed patients and is present in aqueous solutions. There is no standardization of sensitivity for this bacterium and few antibiotics have been tested for non-fermenting glucose bacteria. Due to the reduced antimicrobial sensitivity profile demonstrated by R. pichettii, it is important to correctly identify this etiologic agent in conjunctivitis and keratitis. This case report illustrates that R. Pickettii is a more important pathogen than previously thought.

Nonsurgical correction of presbyopia

This study aimed to describe the basic optical properties for presbyopia correction, including eyeglasses and contact lenses. Conventional eyeglasses are the most established technology for presbyopia correction, and contact lenses have been recognized to have a huge potential in presbyopia correction. However, successful treatment using contact lenses is dependent on age-related factors, such as upper and lower eyelid movements, palpebral aperture, and decreased lacrimal secretion and tear stability. Monovision and multifocality are optical properties of the lens that form the basis of presbyopia correction. The monovision method is based on the principle of neuro-adaptation, wherein one eye automatically selects a clear image and suppresses an unclear image for processing in the brain when there is a difference in the clarity of the images obtained from both the eyes because of anisopia, which is characterized by unequal visual power between the two eyes. Simultaneous views of near and far objects cannot be achieved using eyeglasses, but these can be realized using contact lenses or intraocular lenses. Alternative views of near and far objects can be achieved using a variety of bifocal contact lenses, which function similar to bifocal eyeglasses. Traditional strategies for presbyopia correction, including the use of monovision, bi/tri/multifocal, and progressive eyeglasses and the use of contact lenses, are being challenged by novel strategies involving pharmacotherapy and electrostimulation. Although the immediate prospect of any newly developed innovation remains slim, improved lens profiles would lead to a better match between the lens and the needs of individuals with presbyopia.

Radial Keratoneuritis in Aeromonas Keratitis

PURPOSE: We report a case of Aeromonas keratitis presenting as radial keratoneuritis. CASE SUMMARY: A 33-year-old woman with a history of cleaning her contact lenses with tap water presented with decreased visual acuity for 1 day in the left eye. The patient showed diffuse corneal edema, stromal infiltration, and radial keratoneuritis, which were thought to be pathognomonic for Aeromonas keratitis. Based on the patient's clinical findings and past history, a diagnosis of Aeromonas keratitis was made and she was prescribed topical fortified cefazolin (50 mg/mL, 5%), tobramycin (3 mg/mL), and 0.02% chlorhexidine per hour. Culture results from the contact lens and contact lens solution confirmed infection by Aeromonas hydrophilia. Polymerase chain reaction results for Aeromonas were negative. After 8 days of treatment, the uncorrected visual acuity was 0.7/0.3 with improvement in her corneal findings. CONCLUSIONS: Radial keratoneuritis is not always pathognomic for Aeromonas keratitis and can be present in Aeromonas keratitis. Therefore, ophthalmologists should be cautious when interpreting this clinical sign.