Piggyback corneal como alternativa en el tratamiento del queratocono

El queratocono es una afección inflamatoria, es una ectasia corneal que se caracteriza por un aumento de la curvatura corneal. Se describe como una enfermedad progresiva y asimétrica asociada con cambios estructurales en la organización del colágeno corneal. Existen diferentes opciones terapéuticas con el objetivo de estabilizar la superficie corneal, mejorar la visión y evitar su progresión. El sistema piggyback consiste en adaptar un lente rígido de gas permeable con alta permeabilidad al oxígeno sobre un lente de contacto hidrofílico, es ideal para pacientes que requieren la óptica de un lente de contacto rígido, pero tienen dificultades con su material. Se indica cuando existe una intolerancia a los lentes rígidos de gas permeable, en córneas irregulares y con curvaturas avanzadas. Se presenta una paciente de 24 años de edad con diagnóstico de queratocono desde los 10 años de edad que se corregía con lente rígido de gas permeable. Acudió a consulta del servicio de córnea del Instituto Cubano de Oftalmología Ramón Pando Ferrer, en el año 2010 porque comenzó a presentar intolerancia a los lentes. Debido a que la paciente no presentaba criterio quirúrgico y tenía una agudeza visual mejor corregida con lentes de 1,0 en ambos ojos, se decidió realizar el tratamiento con piggyback corneal. Pese al seguimiento, como parte de la progresión de la enfermedad, a los 10 años de mantenerse con el piggyback, presentó un hidrops corneal agudo, el cual fue tratado. En la actualidad la paciente mantiene seguimiento anual por consulta, sin progresión del queratocono y sin complicaciones con el tratamiento de piggyback corneal.

Keratoconus is an inflammatory condition, a corneal ectasia characterized by increased corneal curvature. It is described as a progressive and asymmetric disease associated with structural changes in the organization of corneal collagen. There are different therapeutic options to stabilize the corneal surface, improve vision and prevent progression. The piggyback system consists of fitting a rigid gas permeable lens with high oxygen permeability over a hydrophilic contact lens, it is ideal for patients who require the optics of a rigid contact lens, but have difficulties with its material. It is indicated when there is intolerance to rigid gas permeable lenses, in irregular corneas and with advanced curvatures. We present a 24-year-old female patient with a diagnosis of keratoconus since she was 10 years old, which was corrected with a rigid gas permeable lens. She went to the cornea service of the Cuban Institute of Ophthalmology Ramón Pando Ferrer, in 2010 because she began to present intolerance to lenses. Since the patient did not present surgical criteria and had a visual acuity better corrected with 1.0 lenses in both eyes, it was decided to perform corneal piggyback treatment. Despite the follow-up, as part of the progression of the disease, after 10 years of piggyback, she presented an acute corneal hydrops, which was treated. At present, the patient maintains annual follow-up via consultation, without progression of keratoconus and without complications with the corneal piggyback treatment.

Translation and validation of the Portuguese version of the Keratoconus Outcomes Research Questionnaire (KORQ) / Tradução e validação do Keratoconus Outcomes Research Questionnaire (KORQ)

ABSTRACT Purpose: The purpose of this study is to translate and validate a Portuguese version of the Keratoconus Outcomes Research Questionnaire. The Keratoconus Outcomes Research Questionnaire is a psychometrically robust and valid instrument used to assess the impact of keratoconus on activity limitations and symptoms. Methods: We performed a translation, cross-cultural adaptation, and validation of the Portuguese version of the Keratoconus Outcomes Research Questionnaire. The initial translation of the English version to the Portuguese language was performed by two independent native speaker translators, followed by an interdisciplinary panel evaluation of the translated version. The Portuguese version was then back-translated into English by two independent native speakers, followed by evaluation and comparison with the original English version by the same interdisciplinary panel. For subsequent validation, the translated questionnaire was administered at two different times to a population of 30 subjects, and the results were compared in a concordance analysis. Results: The translation into Portuguese and back-translation were determined to be correct. Thirty participants were enrolled in the study (mean age, 29.23 ± 7.56 years). Nine questions (31%) had almost perfect agreement (questions 3, 4, 5, 8, 18, 22, 27, 28, and 29), 15 questions (51.7%) had substantial agreement (questions 1, 2, 6, 7, 9, 12, 14, 15, 16, 17, 20, 21, 23, 25, and 26), 4 questions (13.8%) had moderate agreement (questions 10, 11, 19, and 24) and 1 question (3.5%) had reasonable agreement (question 13). High-correlation coefficients were obtained when comparing results of the initial application and second application of this questionnaire to a sample of 30 individuals, which indicated excellent concordance with regard to results, repeatability, and reliability. Conclusions: This translated and validated questionnaire can be applied to a larger population with the intent to assess quality of life in keratoconus patients in the overall Brazilian population as well as in distinct regions of the country.

RESUMO Objetivo: Desenvolver a versão em Português do Keratoconus Outcomes Research Questionnaire (KORQ). O Keratoconus Outcomes Research Questionnaire é um instrumento psicometricamente válido e robusto para avaliação do impacto do ceratocone na limitação de atividades e sintomas. Métodos: Foi realizado no estudo a tradução, adaptação transcultural e validação em Português do Keratoconus Outcomes Research Questionnaire. A tradução inicial da versão em inglês para o idioma português foi realizada por dois tradutores de língua nativa inglesa independentes, seguida de uma avaliação interdisciplinar da versão traduzida. Após isso, a versão em Português foi traduzida novamente para o inglês por dois tradutores nativos de língua portuguesa independentes, seguida de avaliação e comparação com a versão original em inglês pelo mesmo painel interdisciplinar. Para a subsequente validação, o questionário traduzido foi aplicado em dois tempos diferentes em uma população de 30 indivíduos, e os resultados foram comparados em uma análise de concordância. Resultados: O processo de tradução para a língua portuguesa e tradução reversa do questionario Keratoconus Outcomes Research Questionnaire foi conduzido de maneira satisfatória. Trinta participantes foram incluídos no estudo (média idade, 29.23 ± 7.56 anos). Nove questões (31%) com concordância quase perfeita (questões 3, 4, 5, 8, 18, 22, 27, 28 e 29), cinco questões (51.7%) com concordância substancial (questões 1, 2, 6, 7, 9, 12, 14, 15, 16, 17, 20, 21, 23, 25 e 26), quatro questões (13.8%) com concordância moderada (questões 10, 11, 19 e 24) e uma questão (3.5%) com concordância razoável (questão 13). Os altos coeficientes de correlação obtidos ao comparar os resultados da aplicação inicial com a re-aplicação do questionário em uma amostra de 30 indivíduos indicam a excelente concordância em relação aos resultados, repetibilidade e confiabilidade. Conclusão: Esse questionário traduzido e validado pode ser aplicado em populações maiores com o objetivo de avaliar a qualidade de vida em pacientes com ceratocone na população brasileira em geral, assim como em regiões distintas do país.

Prevalencia de pacientes con queratocono en la Clínica Barraquer en Bogotá, Colombia / Prevalence of keratoconus patients at the Barraquer Clinic in Bogotá, Colombia

Introducción: Queratocono es un término clínico amplio, que describe un estado de la córnea derivado de su adelgazamiento focal y protrusión secundaria central, paracentral y/o periférica. Los reportes epidemiológicos globales revelan un amplio rango en cifras de prevalencia e incidencia que se podría explicar por las diferencias geográficas, factores de riesgo, tipo de población, métodos y criterios diagnósticos utilizados. En Colombia no hay estudios epidemiológicos que evalúen esta enfermedad de manera integral por lo que su frecuencia aún no ha podido ser determinada. Objetivo: identificar la prevalencia de Queratocono y Degeneración Marginal Pelucida (DMP) en el centro oftalmológico privado Clínica Barraquer, durante el periodo de tiempo comprendido entre enero de 2014 y enero de 2019. Diseño del estudio: estudio transversal de fuentes secundarias. Método: revisión de los registros médicos electrónicos de todos los pacientes que consultaron por primera vez; posteriormente, se filtraron por el diagnóstico de Ectasia Corneal y/o Queratocono. Cada una de las historias clínicas fue analizada por un oftalmólogo teniendo en cuenta los diagnósticos preestablecidos. Resultados: del grupo de 91.426 pacientes, 2.647 tenían Queratocono o DMP. Se estableció una prevalencia de Queratocono y DMP del 2.84%. La edad promedio al momento del diagnóstico fue de 29.7±12 años. El 42.8% eran mujeres y el 57.2% hombres. Conclusión: la ectasias corneales de tipo Queratocono y DMP, son enfermedades con una prevalencia significativa en la población colombiana evaluada en la clínica Barraquer; consideramos se requiere de programas de tamizaje visual para su detección y tratamiento oportunos.

Background: Keratoconus is a wide clinical term used to describe a corneal disease characterized by thinning and secondary central, paracentral or peripheral protrusion of the cornea. The global epidemiological reports reveal a wide range of prevalence and incidence, that may be explained by geographical differences, risk factors, kind of population, and methods and diagnostic criteria employed. There are no epidemiological studies to evaluate globally this disease in Colombia, therefore, its frequency has not been determined yet. Objective: to identify the prevalence of Keratoconus and Pellucid Marginal Degeneration (PMD) from January 2014 to January 2019 at the private ophthalmological center Clínica Barraquer. Study Design: cross-sectional study using secondary data. Method: a review of the electronic medical records of all patients who consulted for the first time was performed, and then, filtered by the initial diagnosis of Corneal Ectasia or Keratoconus. Each one of the medical records was analyzed by an ophthalmologist taking into account a series of pre-established diagnostic criteria. Results: of 91.426 patients, 2.647 had Keratoconus or PMD within the time interval of the study. A prevalence of 2.84% was determined in first time patients. The average age at the time of diagnosis was 29.7±12 years. 42.8% were female patients and 57.2% male patients. Conclusion: Keratoconus and PMD are diseases with significant prevalence in the Colombian population evaluated at the Barraquer clinic, thus, visual screening programs are required for accurate detection and treatment.

Current status of accelerated corneal cross-linking.

Corneal cross-linking with riboflavin is a technique to stabilize or reduce corneal ectasia, in diseases such as keratoconus and post-laser-assisted in situ keratomileusis (LASIK) ectasia. There is an interest by patient as well as clinicians to reduce the overall treatment time. Especially, the introduction of corneal cross-linking in combination with corneal laser surgery demands a shorter treatment time to assure a sufficient patient flow. The principles and techniques of accelerated corneal cross-linking is discussed.

Deep anterior lamellar keratoplasty for the management of iatrogenic keratectasia occurring after hexagonal keratotomy.

Iatrogenic keratectasia has been reported subsequent to refractive surgery or trauma. Hexagonal keratotomy (HK) is a surgical incisional technique to correct hyperopia. A number of complications have been reported following this procedure, including irregular astigmatism, wound healing abnormalities and corneal ectasia. When visual acuity is poor because of ectasia or irregular astigmatism and contact lens fitting is not possible, penetrating or lamellar keratoplasty can be performed. Since incisions in refractive keratotomy are set at 90–95% depth of cornea, intraoperative microperforations are known to occur and lamellar keratoplasty may become difficult. We describe deep anterior lamellar keratoplasty (DALK) used to successfully manage keratectasia after HK. Pre DALK vision was 20/400 and post DALK vision was 20/30 two months after surgery. This report aims to show improved visual outcome in corneal ectasia secondary to HK. DALK can be a procedure of choice with proper case selection.

Lentes de contacto rígidos gas permeables esclerales, una opción terapéutica en el tratamiento de enfermedades de la superficieocular / Rigid escleral gas permeable contact lenses, a therapeutic option in the ocular surface diseases treatment

Los lentes de contacto esclerales han mantenido un pequeño pero valioso lugar entre los lentes de contacto en la práctica clínica. Es evidente que, debido a la poca instrucción del lente escleral, no se le hadado una alta prioridad en el ámbito profesional, lo que conlleva a que muchos profesionales no tengan una comprensión de sus ventajas intrínsecas y, en consecuencia, rara vez se prescribe o recomienda su uso. Este tipo de lentes rígidos gas permeables desempeñan un papel importante y no se valoran suficientemente en el tratamiento de enfermedades corneales, así como su beneficio para la rehabilitación visual de ectasias, astigmatismos irregulares y en la terapia de la enfermedad de la superficie ocular.

Scleral contact lenses lenses have maintained a small but uniquely valuable place within the contact lenses in clinical practice. It is obvious that due to poorly educated scleral lens has not been given a high priority in the professional field which implies that many professionals do not have an understanding of their intrinsic merits and therefore rarely prescribedor recommended for use. This type of rigid gaspermeable lenses performs an important role and its underrated in the treatment of corneal diseases and their performance for the rehabilitation of visual ecstasies, irregular astigmatism, and therapy of disease of the ocular surface.

Keratectasia after Laser in Situ Keratomileusis: Clinicopathologic Case Report

PURPOSE: To describe the morphological features of a prominent ectasia of the cornea after laser in situ keratomileusis (LASIK). METHODS: The morphology of the ectatic corneas were examined using corneal topography, optical microscopy and transmission electron microcopy in 2 cases who had undergone penetrating keratoplasty due to a poor visual acuity induced by progressive corneal ectasia after LASIK. RESULTS: On a topographic examination, the apex of the corneal surface was observed within the central 3 mm zone and the smallest thickness was 116 micrometer and 271 micrometer in each case. The histological examination showed that the epithelial layer had become thinner and detached easily. The Bowman's membrane was broken down and folded. An irregular arrangement of the stromal lamellae with the fibroblastic keratocytes was found. Scar tissue was observed between the epithelium and the Bowman's layer in the central region. In contrast, the corneal endothelium was intact and no abnormality was found in both cases. CONCLUSIONS: The morphologic examination of 2 cases with corneal ectasia revealed a forward protrusion of both the anterior and posterior corneal surface. In addition epithelial detachment, breakage and folding of the Bowman's membrane and irregular lamellae were found. The 2 cases had greatly thinned and protruding corneas, yet there was no abnormality in the corneal endothelium.

Risk Factors and Clinical Evaluation for Corneal Ectasia after LASIK

PURPOSE: To describe the clinical evaluation of corneal ectasia after laser in situ keratomileusis (LASIK) and evaluate risk factors. METHODS: Sixteen patients (21 eyes) who had undergone LASIK with corneal ectasia from 1997 to 1999 were reviewed retrospectively. The uncorrected visual acuity, best-corrected visual acuity (BCVA), spherical equivalent (SE), pachymetry, keratometry, intraocular pressure (IOP) and corneal topography were measured before and after LASIK. The targeted residual bed thickness (TRBT) and the ablation percentage of the total corneal thickness were checked. To determine risk factors, we reviewed 60 eyes with uneventful LASIK for 4 years after LASIK. The control group was selected with matched preoperative SE and TRBT similar to the ectasia group. RESULTS: Five (31.3%) of 16 patients developed ectasia bilaterally and the rate of preoperative asymmetric bow-tie pattern was 64.7% in corneal topography. At the final post-LASIK follow-up, disagreement of apices location on anterior and posterior was 33.3% in the right eye and 50.0% in the left eye. The mean time to onset of ectasia was 26.9 15.1 months and 28.6% developed ectasia after more than 40 months after LASIK. In the ectasia group, pachymetry before LASIK, TRBT and pachymetry at postoperative 2 months were thinner than the control group (p<0.05). CONCLUSIONS: Asymmetric bow tie pattern showed a high frequency in the corneal topography of the ectasia group before LASIK and about 1/3 of the cases developed ectasia more than 3 years after LASIK. The incidence of pachymetry before and after LASIK and TRBT was related to the development of ectasia.