Aberrometría corneal en el queratocono subclínico

Objetivo: Determinar parámetros aberrométricos de la córnea para la detección del queratocono subclínico. Métodos: Se realizó un estudio observacional, analítico de corte transversal que incluyó 36 pacientes con queratocono subclínico (grupo de estudio) y 36 estudiantes con córneas aparentemente sanas (grupo control), que asistieron a la consulta de córnea del Instituto Cubano de Oftalmología Ramón Pando Ferrer, entre mayo de 2018 y junio de 2022. Se analizaron topografía y aberrometría corneal con el tomógrafo corneal Pentacam AXL. Resultados: El grupo queratocono subclínico mostró valores similares para la queratometría, asfericidad corneal, paquimetría y el valor total de desviación en comparación con el grupo normal. Hubo diferencias estadísticamente significativas en los parámetros aberrométricos, como el coma a 90º (Z3 -1), y la raíz cuadrada media de las aberraciones de alto orden, de cara anterior, posterior y total corneal, en queratocono subclínico en comparación con el grupo normal. El coma posterior a 90º presentó un área bajo la curva (0,894) mayor dentro de las aberrometrías, con un punto de corte de -0,013 μm, con sensibilidad del 86,1 % y especificidad del 88,9 %. Conclusiones: El coma posterior a 90º (parámetro aberrométrico) presenta una alta sensibilidad y especificidad para el diagnóstico de queratocono subclínico, mediante el análisis tomográfico Pentacam AXL.

Objective: To determine corneal aberrometric parameters for the detection of subclinical keratoconus. Methods: An observational, analytical, cross-sectional study was performed including 36 patients with subclinical keratoconus (study group) and 36 students with apparently healthy corneas (control group), who attended the cornea consultation at the Cuban Institute of Ophthalmology Ramón Pando Ferrer, between May 2018 and June 2022. Corneal topography and aberrometry were analyzed with the Pentacam AXL corneal tomographer. Results: The subclinical keratoconus group showed similar values for keratometry, corneal asphericity, pachymetry and total deviation value compared to the normal group. There were statistically significant differences in aberrometric parameters, such as coma at 90° (Z3-1), and root mean square of high-order anterior, posterior and total corneal aberrations in subclinical keratoconus compared to the normal group. The 90° posterior coma presented a higher area under the curve (0.894) within the aberrometries, with a cutoff point of -0.013 μm, with sensitivity of 86.1 % and specificity of 88.9 %. Conclusions: Coma posterior to 90º (aberrometric parameter) presents high sensitivity and specificity for the diagnosis of subclinical keratoconus, using Pentacam AXL tomographic analysis.

Densitometría corneal en el queratocono

Objetivo: Evaluar la densitometría corneal en pacientes con queratocono. Métodos: Se realizó un estudio observacional descriptivo de corte transversal que incluyó 90 pacientes con queratocono (grupo de estudio) y 30 estudiantes con córneas aparentemente sanas (grupo control), que asistieron a la consulta de córnea del Instituto Cubano de Oftalmología Ramón Pando Ferrer, entre mayo del 2018 y junio del 2019. Se seleccionó el ojo derecho de cada caso. Se analizaron densitometría corneal con el tomógrafo corneal Pentacam AXL. Resultados: La densitometría fue mayor en el queratocono respecto a la córnea aparentemente sana, de 0 a 2 mm, en la capa anterior, central, y posterior, respectivamente (p < 0,001). La densitometría aumentó en los 0 a 2 mm en la capa anterior en el grupo moderado y en el grupo avanzado (p < 0,001), y entre los 2-6 mm en la capa central, de 10,86 ± 0,54 en el control, en el queratocono avanzado a 12,35 ± 1,16 y en el moderado a 12,16 ± 1,45 (p < 0,001). La densitometría aumentó en el avanzado de 27,64 ± 3,81, de 22,77 ± 2,14 en el leve, y de 24,04 ± 2,83 en el moderado y en los 0-2 mm, en la capa anterior. Conclusiones: La densitometría es mayor en la córnea queratocónica respecto a la córnea aparentemente sana, además que se incrementa al aumentar la gravedad del queratocono en el área central.

Objective: To evaluate corneal densitometry in patients with keratoconus. Methods: A cross-sectional descriptive observational cross-sectional study was performed including 90 patients with keratoconus (study group) and 30 students with apparently healthy corneas (control group), who attended the cornea consultation at the Cuban Institute of Ophthalmology Ramón Pando Ferrer, between May 2018 and June 2019. The right eye of each case was selected. Corneal densitometry was analyzed with the Pentacam AXL corneal tomographer. Results: Densitometry was higher in keratoconus relative to apparently healthy cornea, from 0 to 2 mm, in the anterior, central, and posterior layer, respectively (p < 0.001). Densitometry increased in the 0 to 2 mm in the anterior layer in the moderate group and in the advanced group (p < 0.001), and between 2-6 mm in the central layer, from 10.86 ± 0.54 in the control, in the advanced keratoconus to 12.35 ± 1.16 and in the moderate to 12.16 ± 1.45 (p < 0.001). Densitometry increased in advanced from 27.64 ± 3.81, from 22.77 ± 2.14 in mild, and from 24.04 ± 2.83 in the moderate and 0-2 mm, in the anterior layer. Conclusions: Densitometry is higher in the keratoconic cornea with respect to the apparently healthy cornea, moreover it increases with increasing severity of keratoconus in the central area.

Results of one decade of optical keratoplasty in pediatric patients.

BACKGROUND: Keratoplasty in the pediatric population has been considered a high-risk procedure. OBJECTIVE: To know the demographic data of patients younger than 18 years treated with optical keratoplasty, indications for surgery and its results. MATERIAL AND METHODS: A retrospective study was carried out at Conde de Valenciana Ophthalmology Institute, in which the medical records of patients younger than 18 years treated with optical keratoplasty from 2009 to 2019 were analyzed. RESULTS: A total of 53 eyes were included. The most common diagnosis and procedure were keratoconus and penetrating keratoplasty, respectively. Mean initial visual acuity was 2.05 ± 0.99 logMAR, and 0.82 ± 1.33 at last visit. Survival time was 130.34 months. Four failures were recorded. As for associated surgeries, corneal wound closure was recorded in seven eyes prior to transplant; during the keratoplasty procedure, anterior vitrectomy in two eyes, and after the transplant, Ahmed valve implantation and re-suture. A total of eight eyes had glaucoma, five of them diagnosed prior to transplantation. Regarding rejection, 15 eyes had an episode during follow-up, and mean time to transplant rejection was 10.8 months. CONCLUSION: Prolonged graft survival can be achieved with better knowledge and management of different associated factors.

ANTECEDENTES: La queratoplastia en población pediátrica ha sido considerada un procedimiento de alto riesgo. OBJETIVO: Conocer datos demográficos de pacientes menores de 18 años tratados con queratoplastia óptica, indicaciones de la cirugía y sus resultados. MATERIAL Y MÉTODOS: Se realizó un estudio retrospectivo en el Instituto de Oftalmología Conde de Valenciana, en el que se revisaron expedientes de pacientes menores de 18 años tratados con queratoplastia óptica de 2009 a 2019. RESULTADOS: Un total de 53 ojos fueron incluidos. El diagnóstico y el procedimiento más comunes fueron el queratocono y la queratoplastia penetrante. El promedio de agudeza visual inicial fue de 2.05 ± 0.99 logMAR y en la última visita, 0.82 ± 1.33. El tiempo de supervivencia del injerto fue de 130.34 meses. Se registraron cuatro fallas. En cuanto a las cirugías asociadas, antes del trasplante se registró cierre de herida corneal en siete ojos y durante la queratoplastia, vitrectomía anterior en dos ojos y después del trasplante, implante de válvula de Ahmed y resutura. Un total de ocho ojos tuvieron glaucoma, cinco con diagnóstico antes del trasplante. Respecto al rechazo, 15 ojos tuvieron un episodio durante el seguimiento y el tiempo promedio de rechazo al trasplante fue de 10.8 meses. CONCLUSIÓN: Se puede lograr una supervivencia prolongada del injerto con el mejor conocimiento y manejo de los diferentes factores asociados.

Resultados de una década de queratoplastia óptica en pacientes pediátricos / Results of one decade of optical keratoplasty in pediatric patients

Resumen Antecedentes: La queratoplastia en población pediátrica ha sido considerada un procedimiento de alto riesgo. Objetivo: Conocer datos demográficos de pacientes menores de 18 años tratados con queratoplastia óptica, indicaciones de la cirugía y sus resultados. Material y métodos: Se realizó un estudio retrospectivo en el Instituto de Oftalmología Conde de Valenciana, en el que se revisaron expedientes de pacientes menores de 18 años tratados con queratoplastia óptica de 2009 a 2019. Resultados: Un total de 53 ojos fueron incluidos. El diagnóstico y el procedimiento más comunes fueron el queratocono y la queratoplastia penetrante. El promedio de agudeza visual inicial fue de 2.05 ± 0.99 logMAR y en la última visita, 0.82 ± 1.33. El tiempo de supervivencia del injerto fue de 130.34 meses. Se registraron cuatro fallas. En cuanto a las cirugías asociadas, antes del trasplante se registró cierre de herida corneal en siete ojos y durante la queratoplastia, vitrectomía anterior en dos ojos y después del trasplante, implante de válvula de Ahmed y resutura. Un total de ocho ojos tuvieron glaucoma, cinco con diagnóstico antes del trasplante. Respecto al rechazo, 15 ojos tuvieron un episodio durante el seguimiento y el tiempo promedio de rechazo al trasplante fue de 10.8 meses. Conclusión: Se puede lograr una supervivencia prolongada del injerto con el mejor conocimiento y manejo de los diferentes factores asociados.

Abstract Background: Keratoplasty in the pediatric population has been considered a high-risk procedure. Objective: To know the demographic data of patients younger than 18 years treated with optical keratoplasty, indications for surgery and its results. Material and methods: A retrospective study was carried out at Conde de Valenciana Ophthalmology Institute, in which the medical records of patients younger than 18 years treated with optical keratoplasty from 2009 to 2019 were analyzed. Results: A total of 53 eyes were included. The most common diagnosis and procedure were keratoconus and penetrating keratoplasty, respectively. Mean initial visual acuity was 2.05 ± 0.99 logMAR, and 0.82 ± 1.33 at last visit. Survival time was 130.34 months. Four failures were recorded. As for associated surgeries, corneal wound closure was recorded in seven eyes prior to transplant; during the keratoplasty procedure, anterior vitrectomy in two eyes, and after the transplant, Ahmed valve implantation and re-suture. A total of eight eyes had glaucoma, five of them diagnosed prior to transplantation. Regarding rejection, 15 eyes had an episode during follow-up, and mean time to transplant rejection was 10.8 months. Conclusion: Prolonged graft survival can be achieved with better knowledge and management of different associated factors.

Modelo animal de ectasia corneal en conejo mediante inyección intraestromal de colagenasa tipo ii / Animal model of corneal ectasia in rabbits by intrastromal injection of type II collagenase

Introducción La colagenasa ii ha sido utilizada para inducir queratocono experimental en modelos animales. Sin embargo, no ha sido estudiado su efecto cuando se administra por inyección intraestromal, por lo que el propósito de este estudio fue estudiar los efectos de la inyección intraestromal de colagenasa ii sobre la superficie corneal y la morfología de la córnea. Método Se trabajó con 6 conejos Nueva Zelanda, se administró colagenasa ii por inyección intraestromal (5μL de 2,5mg/mL) en los ojos derechos y solución salina balanceada en los ojos izquierdos. Se realizaron queratometrías para evaluar la alteración de la curvatura, también al séptimo día se obtuvieron las córneas y se realizó tinción hematoxilina-eosina para examinar los cambios morfológicos. Asimismo, se investigaron los cambios en la expresión de colágeno tipo i por tinción rojo sirio y PCR semicuantitativa. Resultados K1, K2 y Km presentaron diferencias en los promedios con cambios estadísticamente significativos. Los cambios morfológicos que se demostraron fueron degradación y disposición irregular del estroma corneal, incremento en la densidad celular de queratocitos y ligera infiltración celular. Finalmente se demostró que hay mayor expresión de fibras de colágeno tipo i en el grupo experimental a diferencia de los controles y el grosor de las fibras también aumentó por acción de la colagenasa ii; sin embargo, en cuestión génica no hubo cambios en la expresión de colágeno tipo i a nivel molecular entre el grupo control y experimental. Conclusiones La colagenasa ii administrada por inyección intraestromal es capaz de inducir cambios en la superficie corneal y el estroma, pudiendo simular un modelo de queratocono (AU)

Introduction Collagenase II has been used to induce experimental keratoconus in animal models. However, its effect when administered by intrastromal injection has not been studied, so the purpose of this study was to study the effects of intrastromal injection of collagenase II on corneal surface and corneal morphology. Method Six New Zealand rabbits were used, collagenase II was administered by intrastromal injection (5μL of 2.5mg/mL) in the right eyes and balanced salt solution in the left eyes. Keratometry was performed to evaluate curvature alteration, also at day 7 corneas were obtained and hematoxylin–eosin staining was performed to examine morphologic changes. Likewise, changes in type I collagen expression were investigated by Sirius Red staining and semi-quantitative PCR. Results K1, K2, and Km presented differences in the means with statistically significant changes. The morphological changes that were demonstrated were degradation and irregular arrangement of the corneal stroma, increase in the cellular density of keratocytes and slight cellular infiltration. Finally, it was demonstrated that there is greater expression of type I collagen fibers in the experimental group as opposed to the controls and the thickness of the fibers also increased due to the action of collagenase II, however, in terms of genetics there were no changes in the expression of type I collagen at molecular level between the control and experimental groups. Conclusions Collagenase II administered by intrastromal injection is able to induce changes in the corneal surface and stroma, being able to simulate a model of keratoconus (AU)

Animal model of corneal ectasia in rabbits by intrastromal injection of type II collagenase.

INTRODUCTION: Collagenase II has been used to induce experimental keratoconus in animal models. However, its effect when administered by intrastromal injection has not been studied, so the purpose of this study was to study the effects of intrastromal injection of collagenase II on corneal surface and corneal morphology. METHODS: Six New Zealand rabbits were used, collagenase II was administered by intrastromal injection (5µL of 2.5mg/mL) in the right eyes and balanced salt solution in the left eyes. Keratometry was performed to evaluate curvature alteration, also at day 7 corneas were obtained and Hematoxylin-Eosin staining was performed to examine morphologic changes. Likewise, changes in type I collagen expression were investigated by Sirius Red staining and semiquantitative PCR. RESULTS: K1, K2 and Km presented differences in the means with statistically significant changes. The morphological changes that were demonstrated were degradation and irregular arrangement of the corneal stroma, increase in the cellular density of keratocytes and slight cellular infiltration. Finally, it was demonstrated that there is greater expression of type I collagen fibers in the experimental group as opposed to the controls and the thickness of the fibers also increased due to the action of collagenase II, however, in terms of genetics there were no changes in the expression of type I collagen at molecular level between the control and experimental groups. CONCLUSIONS: Collagenase II administered by intrastromal injection is able to induce changes in the corneal surface and stroma, being able to simulate a model of keratoconus.

Características clínico-epidemiológicas del queratocono en Asturia / Clinical-epidemiological characteristics of keratoconus in Asturias

Introducción El queratocono es la ectasia corneal más frecuente y la segunda causa de queratoplastia en el mundo. Las características clínicas y epidemiológicas del queratocono no han sido apenas estudiadas en España y, hasta la fecha, no se ha hecho ningún trabajo en Asturias. Material y métodos Se realizó un estudio transversal analizando todos los casos de queratocono diagnosticado en las primeras consultas de la sección de Córnea y Superficie de los centros Hospital Universitario Central de Asturias (Oviedo) y Hospital Universitario de Cabueñes (Gijón) entre 2017 y 2020. A todos los pacientes se les recogieron datos demográficos, agudeza visual y se les realizó una topografía corneal. Resultados Se incluyeron un total de 112 pacientes (42,0% mujeres y 58,0% hombres). La edad media era de 36,84±15,59, teniendo un 39,3% una edad superior a 40 años. Un 31,8; 28,0; 15,0 y 25,2% se encontraban en los estadios i, ii, iii y iv, respectivamente, en la escala Amsler-Krumeich. En un 7,5% se implantaron segmentos corneales, en un 4,7% se realizó cross-linking y en un 13,2% se realizó queratoplastia. Conclusión Aproximadamente un 40% de los queratoconos se detectan en estadios avanzados y otro 40% a una edad superior a los 40 años. Un 13% de los mismos requieren queratoplastia, por lo que sigue siendo una indicación frecuente en nuestro medio. Es necesario, por tanto, realizar un diagnóstico precoz para actuar antes de que exista una pérdida visual irreversible. (AU)

Introduction Keratoconus is the most frequent corneal ectasia and second most common cause of keratoplasty worldwide. The clinical and epidemiological characteristics of keratoconus have rarely been studied in Spain, and to date, no study has been done in Asturias. Material and methods A cross-sectional study was conducted to analyze all cases of keratoconus diagnosed in the first consultations of the cornea and surface section of the Hospital Universitario Central de Asturias (Oviedo) and Hospital Universitario de Cabueñes (Gijón) between 2017 and 2020. Demographic data, visual acuity and corneal topography were collected. Results A total of 112 patients (42.0% women and 58.0% men) were included. The mean age was 36.84±15.59, with 39.3% being older than 40 years. 31.8%, 28.0%, 15.0%, and 25.2% were in stages i, ii, iii and iv, Amsler–Krumeich scale, respectively. Corneal segments were implanted in 7.5% of patients, cross-linking was performed in 4.7%, and keratoplasty was performed in 13.2%. Conclusion Approximately 40% of keratoconus cases are detected at advanced stages and another 40% are detected at an age over 40 years. 13% of these patients require keratoplasty, which is why it is frequently performed in our setting. Therefore, early diagnosis before irreversible visual loss is necessary. (AU)

Clinical-epidemiological characteristics of keratoconus in Asturias.

INTRODUCTION: Keratoconus is the most frequent corneal ectasia and second most common cause of keratoplasty worldwide. The clinical and epidemiological characteristics of keratoconus have rarely been studied in Spain, and to date, no study has been done in Asturias. MATERIAL AND METHODS: A cross-sectional study was conducted to analyze all cases of keratoconus diagnosed in the first consultations of the Cornea and Surface section of the Hospital Universitario Central de Asturias (Oviedo) and Hospital Universitario de Cabueñes (Gijón) between 2017 and 2020. Demographic data, visual acuity and corneal topography were collected. RESULTS: A total of 112 patients (42.0% women and 58.0% men) were included. The mean age was 36.84 ±â€¯15.59, with 39.3% being older than 40 years. 31.8%, 28.0%, 15.0%, and 25.2% were in stages I, II, III and IV, Amsler-Krumeich scale, respectively. Corneal segments were implanted in 7.5% of patients, cross-linking was performed in 4.7%, and keratoplasty was performed in 13.2%. CONCLUSION: Approximately 40% of keratoconus cases are detected at advanced stages and another 40% are detected at an age over 40 years. 13% of these patients require keratoplasty, which is why it is frequently performed in our setting. Therefore, early diagnosis before irreversible visual loss is necessary.

Pierre Robin sequence and keratoconus, a rare association / Síndrome de Pierre Robin y quearotocono, una rara asociación

Pierre Robin sequence (PRS) is an inherited disorder that affects one in between 8,500 and14,000 people and is characterized by a triad of clinical signs. These include micrognathia,glossoptosis and obstruction of the upper airway, typically associated with palatal cleft.PRS has also been associated with various ocular complications, including high congenitalmyopia, congenital glaucoma, and retinal detachment.Because of the clinical importance of PRS, it is critical to illustrate the features of the Robinsequence to clearly define its primary and secondary clinical signs. We describe a patientwith PRS who developed keratoconus as a rare manifestation of the disease and its management. (AU)

La secuencia de Pierre Robin (PRS) es una patología hereditaria que afecta a una de entre8.500 y 14.000 personas y está caracterizada por una triada de signos. Estos incluyenmicrognatia, glosoptosis y obstrucción de vías aéreas altas, típicamente asociados a labioleporino.PRS ha sido también relacionado con afectación oftalmológica, incluyendo miopía congénita,glaucoma congénito o desprendimiento de retina.Debida a la importancia clínica de la PRS, es fundamental describir las distintascaracterísticas de la secuencia Pierre Robin, para así definir los signos principales ysecundarios de la patología. Describimos el caso de una paciente con PRS que desarrollóqueratocono como una extraña manifestación de la enfermedad. (AU)

Mejoría de la calidad visual, corneal y refractiva en queratocono por medio del protocolo de Atenas / Improvement of visual, corneal, and refractive quality in keratoconus through the Athens protocol

Se presenta el caso de un paciente con queratocono, con distorsión corneal moderada, quien es sometido a cirugía PRK guiada por topografía con crosslinking (protocolo de Atenas), con un excelente resultado anatómico y funcional. Se reportan las imágenes de tomografía de Scheimpflug y la simulación de calidad visual basada en aberrometría Hartmann-Shack.

This article presents the case of a keratoconus patient with moderate corneal distortion who underwent simultaneous topography-guided PRK and corneal crosslinking (Athens protocol), achieving an excellent anatomical and visual improvement. Scheimpflug tomography and Harmann-Shack aberrometry-based visual simulations are presented.

Alternativas terapéuticas del Queratocono / Therapeutic alternatives forkeratoconus / Alternativas terapêuticas para ceratocone

El queratocono es una enfermedad asimétrica, no inflamatoria de origen multifactorial donde diversos factores se ven involucrados; entre los cuales destacan factores genéticos, biomoleculares y ambientales. No precisa causa única por lo cual su tratamiento es variable y depende directamente de la etapa de la enfermedad. Objetivo. El objetivo del artículo es describir las alternativas terapéuticas para el queratocono y los factores de riesgo asociado a la enfermedad. Metodología. Para el desarrollo de la investigación se realizó una revisión bibliográfica de la literatura científica relacionados a las alternativas terapéuticas del queratocono incluyendo estudios observacionales, experimentales analíticos descriptivos. Se utilizo la base de datos PubMed, y Google scholar cuyos documentos fueron publicados entre 2013 a 2022 en idioma español e inglés; se utilizaron los términos MESH y DeCs: "Terapéutica" "queratocono" "factores de riesgo". Conclusión. En la actualidad existen numerosas alternativas terapéuticas, sin embargo, esta va a depender de la etapa de la enfermedad y el grado de afectación corneal. Los tratamientos van desde lentes de contacto hasta la cirugía de trasplante de la córnea. Se aconseja la cirugía lamelar como la mejor opción terapéutica y menores efectos secundarios, ya que, mostrando una rápida recuperación de la capacidad visual en comparación con las otras técnicas.

Keratoconus is an asymmetric, non-inflammatory disease of multifactorial origin where several factors are involved, among which genetic, biomolecular and environmental factors stand out. It does not have a single cause, so its treatment is variable and depends directly on the stage of the disease. Objective. The aim of this article is to describe the therapeutic alternatives for keratoconus and the risk factors associated with the disease. Methodology. For the development of the research, a bibliographic review of the scientific literature related to the therapeutic alternatives for keratoconus was carried out, including observational, experimental, analytical and descriptive studies. The PubMed database was used, and Google scholar whose documents were published between 2013 to 2022 in Spanish and English language; the terms MESH and DeCs: "Therapeutics" "keratoconus" "risk factors" were used. Conclusion. At present there are numerous therapeutic alternatives, however, this will depend on the stage of the disease and the degree of corneal involvement. Treatments range from contact lenses to corneal transplant surgery. Lamellar surgery is advised as the best therapeutic option and has the least side effects, showing a rapid recovery of visual ability compared to other techniques.

O queratocono é uma doença assimétrica, não-inflamatória, de origem multifatorial, onde vários fatores estão envolvidos, incluindo fatores genéticos, biomoleculares e ambientais. Ela não tem uma causa única, portanto seu tratamento é variável e depende diretamente do estágio da doença. Objetivo. O objetivo deste artigo é descrever as alternativas terapêuticas para o queratocono e os fatores de risco associados com a doença. Metodologia. Para o desenvolvimento da pesquisa, foi realizada uma revisão bibliográfica da literatura científica relacionada às alternativas terapêuticas para o queratocono, incluindo estudos observacionais, experimentais, analíticos e descritivos. Utilizamos o banco de dados PubMed e Google scholar cujos documentos foram publicados entre 2013 e 2022 em espanhol e inglês; usamos os termos MESH e DeCs: "Therapeutics" "keratoconus" "risk factors". Conclusão. Existem atualmente inúmeras alternativas terapêuticas, porém, isto dependerá do estágio da doença e do grau de envolvimento da córnea. Os tratamentos variam de lentes de contato a cirurgia de transplante de córnea. A cirurgia lamelar é aconselhada como a melhor opção terapêutica com os menores efeitos colaterais, mostrando uma rápida recuperação da capacidade visual em comparação com outras técnicas.

Early keratometric and refractive results after intra-corneal rings surgery in keratoconus patients.

OBJECTIVE: To evaluate early keratometric and refractive results after intra-corneal rings surgery in keratoconus patients. METHOD: 50 eyes of 25 patients with keratoconus within stage 2 and 3, underwent intra-stromal corneal rings surgery by using the femtosecond surgical laser, one month after surgery, corneal keratometries and patient refraction were compared vs pre-operative ones. RESULTS: Mean pre-operative low keratometry was 48.8 ± 3.65 D vs. 46.44 ± 3.65 D post-operative (p < 0.005). Mean pre-operative high keratometry was 53.92 ± 4.50 vs. 49.65 ± 4.15 post-operative (p < 0.005). Mean pre-operative spherical equivalent was -7.39 ± 2.42 D vs. -3.48 ± 2.47 D post-operative (p < 0.005). Mean pre-operative cylinder was -5.65 ± 2.02 D vs. -3.48 ± 2.47 D post-operative (p < 0.005). CONCLUSIONS: Corneal keratometries, spherical equivalent and corneal cylinder, significant decrease at one month after intra-stromal corneal rings surgery in keratoconus patients.

OBJETIVO: Evaluar los resultados queratométricos y refractivos tempranos de pacientes con queratocono operados con anillos intracorneales. MÉTODO: Se evaluaron 50 ojos de 25 pacientes con queratocono de grado 2 o 3, posoperados con colocación de anillos intracorneales mediante el uso de láser de femtosegundos, al mes del posoperatorio, comparando las queratometrías y las refracciones antes y después de la operación. RESULTADOS: El promedio preoperatorio de las queratometrías planas fue de 48.8 ± 3.65 D y en el posoperatorio fue de 46.44 ± 3.65 D (p < 0.005). El promedio preoperatorio de las queratometrías curvas fue de 53.92 ± 4.50 y en el posoperatorio fue de 49.65 ± 4.15 (p < 0.005). El equivalente esférico preoperatorio fue de −7.39 ± 2.42 D y en el posoperatorio fue de −3.48 ± 2.47 D (p < 0.005). El promedio del cilindro preoperatorio fue de −5.65 ± 2.02 D y en el posoperatorio fue de −3.48 ± 2.47 D (p < 0.005). CONCLUSIONES: La colocación de anillos intracorneales reduce de forma significativa tanto las queratometrías como los equivalentes esféricos y el astigmatismo en pacientes con queratocono en forma temprana.

Efecto de los segmentos anulares intracorneales en la topografía corneal posterior en ojos con queratocono / Effect of intracorneal ring segments on posterior corneal topography in eyes with keratoconus

Objetivo Analizar los cambios en las superficies corneales anterior y posterior medidos con un dispositivo de imágenes Scheimpflug en pacientes con queratocono implantados con segmentos anulares intracorneales y correlacionar esos cambios con los resultados visuales. Métodos Este estudio prospectivo de serie de casos de intervención incluyó 92 ojos de 60 pacientes con queratocono a los que se implantó segmentos anulares intracorneales de Kerarings (Mediphacos, Belo Horizonte, Brasil). Se evaluaron las lecturas queratométricas (K), la asfericidad corneal (valor Q) y las elevaciones de las superficies corneales anterior y posterior mediante un dispositivo de imágenes Scheimpflug antes de la operación y a los uno, 3, 6 y 12 meses después de la misma. Resultados La mejor agudeza visual corregida (MAVC) mejoró de 0,61 a 0,19 logMAR a los 12 meses de la cirugía. Tanto la superficie corneal anterior como la posterior mostraron un aplanamiento significativo con una reducción estadísticamente significativa de la lectura K anterior media en 3,39 D y de la lectura K posterior media en 0,39 D (p<0,001) a los 12 meses. Se observó un cambio estadísticamente significativo del Q anterior a un valor menos negativo (de −1,05 a −0,36) (p<0,001) sin que se produjera ningún cambio significativo en el valor del Q posterior. La mejora del Q anterior se correlacionó significativamente con una mejor MAVC postoperatoria (p=0,03). Una mejor MAVC postoperatoria se correlacionó significativamente con una mejor MAVC preoperatoria, una K anterior y posterior más plana, un valor Q anterior menos prolato y menores elevaciones anteriores. Conclusiones La implantación de segmentos anulares intracorneales tiene un efecto de aplanamiento significativo en las superficies corneales anteriores y posteriores. La mejora de la asfericidad corneal se correlaciona con un mejor resultado visual. Algunos parámetros preoperatorios fueron factores predictivos de la mejora visual postoperatoria (AU)

Purpose To analyze the changes in the anterior and posterior corneal surfaces measured with a Scheimpflug imaging device in keratoconus patients implanted with intracorneal ring segments and to correlate those changes with the visual outcomes. Methods This prospective interventional case series study included 92 eyes of 60 patients with keratoconus who underwent Kerarings (Mediphacos, Belo Horizonte, Brazil) intracorneal ring segments implantation. Keratometric (K) readings, corneal asphericity (Q value) and elevations of both anterior and posterior corneal surfaces were evaluated using a Scheimpflug imaging device preoperatively and at one, 3, 6 and 12 months after surgery. Result The mean best corrected visual acuity (BCVA) improved from 0.61 to 0.19 logMAR at 12 months after surgery. Both anterior and posterior corneal surfaces showed significant flattening with statistically significant reduction of the mean anterior K reading by 3.39 D and the mean posterior K reading by 0.39 D (P<.001) at 12 months. Statistically significant change of the anterior Q to a less negative value (from −1.05 to −0.36) was observed (P<.001) with no significant change of the posterior Q value. Improvement of the anterior Q was significantly correlated to better postoperative BCVA (P=.03). Better postoperative BCVA significantly correlated to better preoperative BCVA, flatter preoperative anterior and posterior K, less prolate anterior Q value and lower anterior elevations. Conclusions Implanted with intracorneal ring segments implantation has a significant flattening effect on both anterior and posterior corneal surfaces. Improvement of corneal asphericity is correlated to better visual outcome. Certain preoperative parameters were predictive factors of the postoperative visual improvement (AU)

Effect of intracorneal ring segments on posterior corneal topography in eyes with keratoconus.

PURPOSE: To analyze the changes in the anterior and posterior corneal surfaces measured with a Scheimpflug imaging device in keratoconus patients implanted with intracorneal ring segments (ICRS) and to correlate those changes with the visual outcomes. METHODS: This prospective interventional case series study included 92 eyes of 60 patients with keratoconus who underwent Kerarings (Mediphacos, Belo Horizonte, Brazil) ICRS implantation. Keratometric (K) readings, corneal asphericity (Q value) and elevations of both anterior and posterior corneal surfaces were evaluated using a Scheimpflug imaging device preoperatively and at 1, 3, 6 and 12 months after surgery. RESULTS: The mean best corrected visual acuity (BCVA) improved from 0.61 to 0.19 logMAR at 12 months after surgery. Both anterior and posterior corneal surfaces showed significant flattening with statistically significant reduction of the mean anterior K reading by 3.39 D and the mean posterior K reading by 0.39 D (p<0.001) at 12 months. Statistically significant change of the anterior Q to a less negative value (from -1.05 to -0.36) was observed (p<0.001) with no significant change of the posterior Q value. Improvement of the anterior Q was significantly correlated to better postoperative BCVA (p=0.03). Better postoperative BCVA significantly correlated to better preoperative BCVA, flatter preoperative anterior and posterior K, less prolate anterior Q value and lower anterior elevations. CONCLUSIONS: ICRS implantation has a significant flattening effect on both anterior and posterior corneal surfaces. Improvement of corneal asphericity is correlated to better visual outcome. Certain preoperative parameters were predictive factors of the postoperative visual improvement.

Bilateral superior keratoconus.

CLINICAL CASE: A 16-year-old man presented at our institute with progressive reduction of vision acuity in both eyes. This patient presented to our corneal service with clinical and topographical features of bilateral superior keratoconus. The clinical features, topographical, Scheimpflug and photographs images findings of a asymmetric bilateral superior keratoconus are presented.

Queratocono superior bilateral / Bilateral superior keratoconus

Varón de 16 años referido en nuestra sección por reducción progresiva de la agudeza visual de ambos ojos. Las características biomicroscópicas y topográficas indicaron el diagnóstico de queratocono bilateral asimétrico con área ectásica superior. Este hallazgo configura un cuadro clínico y variedad de queratocono de infrecuente hallazgo y que debe ser considerado. Se muestran las imágenes de microscópicas, de topografía corneal de elevación y Scheimpflug (AU)

Clinical case A 16-year-old man presented at our institute with progressive reduction of vision acuity in both eyes. This patient presented to our corneal service with clinical and topographical features of bilateral superior keratoconus. The clinical features, topographical, Scheimpflug and photographs images findings of a asymmetric bilateral superior keratoconus are presented (AU)

Translation and validation of the "Questionnaire for research on keratoconus results" (KORQ) in the Colombian population. / Traducción y validación del «Cuestionario para investigación de resultados en queratocono¼ (KORQ) en población colombiana.

OBJECTIVE: It is proposed to carry out a process of translation and adaptation of the "Questionnaire for Research on Keratoconus Results" (KORQ) into Spanish and its validation in a Spanish-speaking population, such as Colombia. This is intended to provide a tool for measuring and monitoring the commitment to quality of life of patients with this corneal ectasia. MATERIAL AND METHODS: A prospective analytical study was carried out, in which 200 subjects diagnosed with keratoconus completed a translated version of the KORQ questionnaire. The internal validity of the questionnaire was evaluated using Cronbach's Alpha, while its construction was evaluated by an Exploratory Factor Analysis, including a Parallel Horn Analysis for the selection of the number of underlying factors. Subsequently, 50 patients were re-selected to complete the questionnaire one week later. The repeatability of the questionnaire was measured by the Spearman test. RESULTS: The KORQ questionnaire in its Spanish version showed some internal validity in both sections. Both sections of the questionnaire showed an essentially unidimensional behaviour. The test-retest repeatability of the test was excellent (Spearman rho> 0.95). CONCLUSIONS: The translated version of the KORQ is valid in Colombian population.

Association between POLG and XRCC1 gene polymorphisms and keratoconus occurrence among Egyptian patients. / Asociación entre polimorfismos de los genes POLG y XRCC1 y aparición de queratocono entre pacientes egipcios.

BACKGROUND: Keratoconus is a progressive disorder distinguished by thinning of the corneal tissue and bulging forward into a cone-shaped fashion. Yet its etiology, which is multifactorial, despite intensive research remains elusive. Corneal exposure a reactive oxygen species causing oxidative DNA damage has been reported to be associated with KC and therefore suggesting that DNA base excision repair mechanism might lie behind the pathogenesis of the disease. METHODS: We studied the association of three variants in two BER genes (XRCC1 and POLG) and QC occurrence in a cohort of patients from Egypt. Genotyping of the three variants was performed using PCR and restriction enzymes analysis. RESULTS: We observed that A allele and A/A genotype of the c.1196A>G variant in the XRCC1 gene were significantly associated with increased KC occurrence while the G allele was associated with decreased KC occurrence. Similarly, the A/A genotype of the c.-1370T>A polymorphism in the POLG gene and the A allele were associated with increased occurrence of KC, while T/A genotype and the T allele were accompanied with decreased occurrence of KC. On the other hand, no association was observed between the c.580C>T variant in the XRCC1 gene and KC occurrence among the studied group of patients. CONCLUSION: Our results suggest that c.1196A>G variant of the XRCC1 and c.-1370T>A variant of the POLG gene may be involved in KC pathogenesis and might be considered as a genetic risk factors of the disease among Egyptian population.

Phakic intraocular lenses: Recent advances and innovations. / Lentes intraoculares fáquicas: recientes avances e innovaciones.

Phakic intraocular lenses (pIOL) are recommended when counselling refractive surgery candidates presenting with high ametropia or ocular surface and/or corneal conditions that contraindicate corneal refractive surgery. This review aims to present the state-of-the-art regarding pIOL models currently available in Europe, addressing their newer indications and recent design innovations. These include, in the case of posterior chamber pIOLs, the addition of a central hole to improve aqueous humour circulation, the availability of larger optical zones, and multifocal optics for the compensation of presbyopia. The review also highlights their good safety and efficacy results, as well as the role of patient education to ensure adequate outcomes in the medium-long term. The indications of pIOLs in special situations, as well as bi-lensectomy, a procedure that most pIOL patients may eventually require as they age and develop cataracts, are also addressed.

Pediatric penetrating keratoplasty and graft rejection: experience at the Hospital Infantil de México Federico Gómez.

Background: Penetrating keratoplasty (PK) is a challenging surgical ocular procedure indicated for some pediatric patients with vision-threatening corneal disease damage. Pediatric PK is reserved for cases with advanced pathology or dysfunction as rejection and failure rates greatly supersede the rates of adult PK. The objective was to identify factors associated with graft rejection and failure amongst Mexican children undergoing primary PK for different indications. Methods: A retrospective review of consecutive pediatric PK medical records was conducted between 2001 and 2015 at the Hospital Infantil de México Federico Gómez. Graft survival was calculated using the Kaplan-Meier survival method. Results: During the 15 years of study, 67 eyes of 57 patients underwent PK. The mean age at the time of surgery was 11 years. The mean follow-up duration was 44 months. Keratoconus was the most common indication for PK (61%) followed by herpetic keratitis (15%) and other corneal dystrophies (10%). Mean graft survival time was 45.6 months (95% confidence interval 31.8-58.4 months, standard deviation = 0.069), with a survival rate of 70% at 1 year. Univariate Cox proportional hazard showed that being < 9 years of age at the time of the surgery (p = 0.023) and corneal dystrophies (p = 0.04) were prognostic factors for corneal rejection. Five eyes of five patients developed graft failure. Conclusions: Pediatric PK patients commonly experience graft rejection, which need to be promptly diagnosed and treated to minimize permanent damage. The age at the time of surgery and congenital corneal opacities is factors associated with a higher risk of rejection and failure.

Introducción: La queratoplastia penetrante (QP) es un procedimiento quirúrgico indicado en algunos pacientes pediátricos con daño corneal con riesgo de fracaso que amenaza la visión. El objetivo del presente trabajo fue identificar los factores asociados a rechazo y fallo del injerto corneal en niños sometidos a QP. Métodos: Serie de casos de pacientes sometidos a QP en el Hospital Infantil de México Federico Gómez entre 2001 y 2015. La sobrevida del injerto fue calculada por el método de estimación de la función de supervivencia Kaplan­Meier. Resultados: Durante 15 años de estudio, 67 ojos de 57 pacientes fueron sometidos a QP. El promedio de edad de los pacientes al tiempo de la cirugía fue de 11 años. El seguimiento promedio fue de 44 meses. El queratocono fue la indicación más común de QP (61%), seguido de queratitis herpética (15%) y otras distrofias corneales (10%). El tiempo promedio de sobrevida fue 45.6% (intervalo de confianza [IC] 95%: 31.8-58.4 meses, desviación estándar [DS] = 0.069), con una tasa de sobrevida del 70% a 1 año. El riesgo proporcional de Cox univariado mostró que una edad < 9 años al momento de la cirugía (p = 0.023) y distrofias corneales (p = 0.04) son factores pronóstico para el rechazo corneal. Cinco ojos de cinco pacientes desarrollaron falla del injerto. Conclusiones: El rechazo del injerto en QP en pacientes pediátricos es común y puede ser resuelto satisfactoriamente en casi todos los casos con diagnóstico y tratamiento. La edad al momento de la cirugía y las opacidades corneales congénitas son factores asociados con el rechazo y fallo.