Prevalence of Refractive Error, Presbyopia, and Spectacle Coverage in Bogotá, Colombia: A Rapid Assessment of Refractive Error.

SIGNIFICANCE: Uncorrected refractive error is the leading cause of visual impairment; therefore, reducing its prevalence is important worldwide. For two decades, there has not been a comprehensive assessment of refractive error in Latin America. PURPOSE: The purpose of this study was to determine the current prevalence of refractive error, presbyopia, spectacle coverage, barriers to uptake refractive services, and spectacle correction in people 15 years and older in Bogotá, Colombia. METHODS: A cross-sectional community-based survey was conducted using 50 randomly selected clusters from 10 districts of Bogotá reflecting the socioeconomic status of the city. Respondents 15 years and older were interviewed and underwent standardized clinical eye examinations. Prevalence of uncorrected refractive error, spectacle coverage, and visual impairment were standardized to 2015 age-sex population distribution of Bogotá and further analyzed. RESULTS: A total of 2886 subjects (90% of 3206 eligible subjects) participated in the study; 39.1% were male and 60.9% were female in the age range of 15 to 96 years, with a median age of 46 years (interquartile range, 45 to 54 years). Age- and sex-standardized prevalence of visual impairment was 19.3% (95% confidence interval [CI], 17.8 to 20.8%). Prevalence of uncorrected refractive error was 12.5% (95% CI, 11.3 to 13.7%). Prevalence of presbyopia among participants 35 years and older was 55.2% (95% CI, 52.9 to 57.4%). Spectacle coverage was 50.9% for distance vision, and it was 33.9% for presbyopia. Main barrier to spectacle uptake was a limitation in affording spectacles because of economic factors (29.5%). CONCLUSIONS: This study provides a current estimate of refractive error using the Rapid Assessment of Refractive Error for Colombia and the Latin American region. The prevalence of uncorrected refractive error and presbyopia was high, and the barriers to spectacle uptake were higher in the lowest socioeconomic strata. The results obtained in the present study will help in making evidence-based decisions related to eye care service delivery in Colombia.

Diferencias en la variación del helecho lagrimal con el uso de lentes de contacto de hidrogel y de hidrogel de silicona / Differences in the patterns of crystallization of tears(ferning test) with the use of hydrogel and silicone

Objetivo: el propósito de esta investigación fue determinarla variación de los patrones del helecho lagrimal en usuarios de lentes blandos de hidrogel y de hidrogel de silicona. Metodología: se adaptaron lentes de contacto de hidrogel (Alphafilcon A) en un ojo, y de hidrogel de silicona Balafilcon A) en el otro ojo, a ocho pacientes no usuarios de lentes anteriormente.Se realizó prueba de cristalización lagrimal antes de la adaptación y a las dos semanas de uso de los lentes, y se clasificaron los patrones del helecholagrimal según la escala de Rolando. Resultados: se encontró un aumento en el grado del patrón del helecholagrimal en el 50% de los usuarios de lentes de hidrogel y en el 50% de los de hidrogel de silicona. Conclusiones: el uso de lentes de contacto blandosde hidrogel y de hidrogel de silicona ocasiona alteraciones en el patrón del helecho lagrimal y no hay diferencia entre los dos tipos de lentes.

Objective: The purpose of this investigation was to determine the variation of tears ferning patterns insoft contact lens wearers of hydrogel and silicone hydrogel. Methods: 8 patients that never have worncontact lenses were fitting with hydrogel contact lenses(Alphafilcon A) in one eye, and silicone hydrogel balafilcon A) in the other eye. Crystallization test was performed before the contact lens fitting andwithin two weeks of lens wear and the patterns were classified according to the scale tear ferning test of Roland. Results: There was an increase in the degree tear fern pattern in 50% of the hydrogel lens wearers and 50% of silicone hydrogel. Conclusions: The useof soft contact lens hydrogel and silicone hydrogel causes changes in the pattern of tear ferns and there are not differences between the two types of lenses.

Ojo seco y cambios citológicos en la conjuntiva en pacientes sometidos a cirugía Lasik / Dry eye and cytological conjunctival changes in patients undergoing LASIK Surgery

El ojo seco es una de las complicaciones más comunes de la cirugía refractiva, persiste por 6 meses o más después de Lasik. Objetivo: evaluar los cambios citológicos en la conjuntiva después de la cirugía Lasik y su relación con el grado de severidad del ojoseco. Metodología: veinticinco pacientes (cincuenta ojos) a los cuales se les realizó cirugía refractiva Lasik en la clínica Optilaser S.A. se evaluaron antes de la cirugía, al mes y 3 meses después de Lasik con las siguientes pruebas: TBUT, Test de Schirmer, biomicroscopía y cuestionario de sintomatología, para diagnosticar el grado de severidad de ojo seco y citología de impresión conjuntival (CIC); las citologías se coloraron con PAS-Hematoxilina, para determinar metaplasia escamosa. Resultados: en el prequirúrgico el 8 por ciento de los pacientes tuvo ojo seco moderado, al mes de la cirugía el 48 por ciento presentó ojo seco moderado y severo, a los 3 meses el porcentaje fue similar (44 por ciento). Antes de la cirugía el 8 por ciento de los ojos tuvo una CIC alterada; al mes y a los 3 meses el 65,3 por ciento de los casos presentó algún grado de metaplasia escamosa (X2=0,000). En el primer control presentaron CIC alterada: el 77,8 por ciento sin ojo seco, el 57,1 por ciento con ojoseco leve, el 59,1 por ciento con ojo seco moderado y el 100 por ciento de los ojos seco severos. Al tercer mes de la cirugíafue similar, el 57,1 por ciento de los ojos secos leves, el 78,6 por ciento de los ojos secos moderados y el 100 por ciento de los severos tenían metaplasia escamosa grado 2, 3 y 4. Conclusiones: la severidad de los cambios citológicos se aumentó significativamente al mes y al tercer mes después de la cirugía. La alteración del epitelio conjuntival contribuye a la patogénesis del ojo seco inducido por la cirugía refractiva.

Dry eye is one of the most common complication sof refractive surgery, persists for 6 months or more after Lasik. Objective: to evaluate the cytological changes in the conjunctiva after Lasik surgery and its relationship with the degree of severity of dry eye. Methods: twenty five patients (50 eyes) to whom underwent Lasik surgery at the clinic Optilaser SA were evaluated before surgery, one month and three months after Lasik with the following tests: TBUT, Schirmer test, slit lamp and symptoms questionnaire for diagnosis and severity of dry eye and conjunctival impression cytology (CIC), the smears were stained with PAS-hematoxylin to determine the degree of squamous metaplasia. Results: in preoperativeto 8 percent of patients had moderate dry eye, a month after surgery 48 percent had moderate to severe dry eye, three months, the percentage was similar (44 percent). Before surgery, the 8 percent of eyes had an altered CIC,one month and three months, 65,3 percent of patients had some degree of squamous metaplasia (X2 = 0,000). In the first control, CIC had altered: 77,8 percent non-dry eye, 57,1 percent with mild dry eye, 59,1 percent with moderate dry eye and 100 percent of severe dry eye. On the third month after surgery was similar, 57,1 percent of mild dry eyes,78,6 percent of moderate dry eyes and 100 percent of squamous metaplasia had severe grade 2, 3 and 4. Conclusion: severity of cytological changes was increased significantly each month and third month after surgery.The alteration of the conjunctival epithelium, contributesto the pathogenesis of dry eye induced by refractive surgery.

Película lagrimal: estructura y funciones / Tear film, structure and function

Un vestigio de la evolución de las formas de vida acuática a la vida terrestre es el sistema lagrimal y su función principal es prevenir la sequedad del segmento anterior del ojo para permitir su funcionamientoen el medio ambiente terrestre. El producto de este sistema es la lágrima y ya en el siglo V a.C., Hipócrates reconocía su importancia. Esta fina películaes muy versátil y tiene gran capacidad de adaptacióna los cambios del entorno; sin embargo, cuandolas condiciones son muy adversas, puede tornarse frágil y reducir su funcionalidad exponiendo al ojo a daños potenciales. La comprensión de la estructura de la película lagrimal es necesaria para diferenciar su funcionamiento normal del anómalo, lo que conllevaríaa un diagnóstico más acertado de las alteracioneslagrimales. Se detallarán las partes correspondientesa los meniscos marginales de los párpados y la película lagrimal propiamente dicha, dada su importanciaen la integridad corneal y ocular. El objetivode esta revisión temática es describir diferentes teorías propuestas sobre la estructura y funciones de la película lagrimal, como base fundamental para el entendimiento de su desempeño clínico.

A vestige of the evolving forms of aquatic life to terrestrial life is the lacrimal system and its main function is to prevent dryness of the anterior segment of the eye to allow their operation in the Earth’s environment. The product of this system is already in tears and the 5th century BC, Hippocrates recognized its importance. This thin film is very versatile and has great ability to adapt to the changing environment, but when conditions are adverse, it may become fragile and reduce its functionality exposing the eye to potential damage. Understanding the structure of the tear film is necessary to differentiate its normal operation of the anomalous, which would lead to a more accurate diagnosis of the lacrimal alterations. It detailed the parties for the meniscus fringe of the eyelids and tear film itself, given its importance in the integrity and corneal eye. The objective of this thematic review is to describe different theories proposals on the structure and functions of the tear film, as the foundation for the understanding of their clinical performance.