Boston Keratoprosthesis type 1 (KPro) without contact lens wearing in end-stage corneal disease: The APEC experience.

PURPOSE: To report the visual outcomes and survival analysis of keratoprosthesis without contact lens wearing in a tertiary eye care hospital in Mexico City, Asociación Para Evitar La Ceguera (APEC, Coyoacán, México). DESIGN: Retrospective cohort with survival analysis. PARTICIPANTS: Twenty-three eyes (22 patients) received KPro type 1 between 2015 and 2020 with a follow-up time of three years. METHODS: We included analyzed data about past medical history, preoperative diagnosis, best-spectacle visual acuity (BSCVA), postoperative complications and retention rate. Univariate, bivariate and survival analysis were performed and reported. RESULTS: The mean age was 58 ± 13.5 years (SD). 60.86% were male patients (14 eyes). Twelve-eyes (52%) achieved a BSCVA of 20/200 or better in the first and second year of follow-up. At 3 years, only 35% achieved 20/200 or better (BSCVA). Retention rate of Boston type 1 KPro was 87% (20 eyes) at 3 years follow-up. The most common complication was retroprosthetic membrane (RPM) which occurred in 9 eyes (39.1%), followed by corneal melting in 7 eyes (30.4%). CONCLUSIONS: We report the results of a retrospective cohort of twenty-three eyes (22 patients) who were implanted with a Boston type 1 KPro without contact lens wearing to treat corneal blindness. BSCVA improved significantly in most patients achieving 20/200 or better at the 2-year follow-up. Retention rate was 87%, with the presence of RPM as the most common complication.

Cataract surgery in patients with underlying keratoconus: focused review.

An underlying diagnosis of keratoconus (KC) can complicate cataract surgery. In this study, the results of a focused review of the literature pertaining to cataract surgery in patients with KC are detailed. Topics essential for the appropriate management of this patient population are discussed. First, the individual and shared epidemiology and pathophysiology of cataract and KC are reviewed. Then, the theory and approach to intraocular lens power calculation are discussed, highlighting particularities and pitfalls of this exercise when performed in patients with KC. Finally, several special-although not uncommon-management scenarios and questions are addressed, such as surgical planning in cases where corneal stabilization or tissue replacement interventions are also necessitated.

SARS-CoV-2 and the Eye: A Relationship for a Possible Prognostic Tool in COVID-19 Patients.

PURPOSE: In December 2019 there was the first report about a new viral infection in Wuhan, China. The new virus was taxonomically designed as Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) causing the coronavirus disease 2019 (COVID-19). SARS-CoV-2 uses the angiotensin-converting enzyme 2 (ACE2) receptor for cell invasion, which is expressed in different tissues including lungs, small intestine, testicles, kidneys, brain, and the eye. The purpose of this article is to review the available information on the relationship of COVID-19 with the eye, as well as evaluating the possible usefulness of ocular diagnostic tests to help in the diagnosis and/or monitoring of patients with this disease. METHODS: We performed a retrospective review of relevant articles from November 2019 to April 2020. RESULTS: Ocular infection by SARS-CoV-2 is still controversial; nevertheless, the possibility of being a viral reservoir has been suggested, increasing the likelihood of infection. Some reports demonstrated the presence of SARS-CoV-2 in tears, and previously published data suggest a pathological increase of cytokine concentrations in COVID-19 patients; the cytokine release syndrome or cytokine storm contributes to lung and central nervous system damage. The usefulness of tears for the measurement of inflammatory cytokines in various diseases is well known, in particular IL-6, which has been correlated to the severity of COVID-19. CONCLUSION: Considering that the IL-6 signaling cascade may be activated in patients with COVID-19, makes it an excellent target for diagnostic and/or monitoring purposes.

Efficacy and Safety of Sodium Hyaluronate/chondroitin Sulfate Preservative-free Ophthalmic Solution in the Treatment of Dry Eye: A Clinical Trial.

Purpose: To evaluate the efficacy of a preservative free sodium hyaluronate/chondroitin sulfate ophthalmic solution (SH/CS-PF) in patients with dry eye disease (DED).Methods: This was a randomized phase IV, multicentric, prospective, double-blind clinical trial. Intent-to-treat (ITT) and per-protocol (PP) analyses were performed. Patients were assigned to receive either SH/CS-PF, Systane® Ultra (PEG/PG) or Systane® Ultra PF (PEG/PG-PF) for 90 days. A total of 326 patients were included in the ITT, and 217 in the PP analysis. Efficacy endpoints were goblet cell density, Nelson's grades (conjunctival impression cytology), tear break-up time (TBUT), Ocular Surface Disease Index (OSDI), and Schirmer's test. Other parameters included were tolerability, measured by the ocular symptomatology; and safety, measured through corneal staining, intraocular pressure, visual acuity and adverse events.Results: In the ITT, there was a significant increase in mean goblet cell density in all treatments compared with their baseline (28.4% vs 21.4% and 30.8%), without difference between arms (p = .159). Eyes exposed to SH/CS-PF, PEG/PG and PEG/PG-PF showed Grade 0-I squamous metaplasia (85.5%, 87.9% and 93.2%, respectively). Similar improvements were observed for TBUT (1.24 ± 2.3s vs 1.27 ± 2.4s and 1.39 ± 2.3s) and OSDI scores at day 90 (-8.81 ± 8.6 vs -7.95 ± 9.2 and -8.78 ± 9.8), although no significant intergroup difference was found. Schirmer's test also presented improvement compared to baseline (1.38 ± 4.9 vs 1.50 ± 4.7 and 2.63 ± 5.9), with a significantly higher variation for PEG/PG-PF. There were no significant differences between treatments for any tolerability and safety parameter, nor between ITT and PP analyses for any outcome.Conclusions: The topical application of SH/CS-PF is as effective, safe and well tolerated as that of PEG/PG or PEG/PG-PF. The results suggest that SH/CS-PF may lead to normalization of clinical parameters and symptom alleviation in patients treated for DED.

Photoactivated Chromophore for Keratitis-Corneal Collagen Cross-Linking (PACK-CXL) Improves Outcomes of Treatment-Resistant Infectious Keratitis.

PURPOSE: To investigate the efficacy of photoactivated chromophore corneal collagen cross-linking (PACK)-CXL in the management of treatment-resistant infectious keratitis. DESIGN: Observational cohort study. PARTICIPANTS: Forty-two eyes from 41 patients with treatment-resistant infectious keratitis. METHODS: Eyes underwent PACK-CXL treatment with the Dresden modified protocol in addition to standard antimicrobial therapy. The primary endpoint was the size of the corneal ulcer. Descriptive statistics, Wilcoxon rank test, McNemar test and Spearman correlation coefficient were used for statistical analysis, and p values lower than 0.05 were considered statistically significant. RESULTS: Success rate at third postoperative month was of 90.5%. Statistical analyses showed a significant effect of (PACK)­CXL with standard antimicrobial therapy to reduce corneal ulcer size (p=0.031). CONCLUSION: As adjuvant therapy to standard antimicrobial treatment, PACK-CXL improves the outcomes in patients with treatment-resistant corneal ulcers.

Translation and validation of the contact lens dry eye questionnaire-8 (CLDEQ-8) to the Spanish language.

PURPOSE: To present the process of cultural and psychometric adaptation, and clinical validation of a new version in the Spanish language of the Contact Lens Dry Eye Questionnaire-8 (CLDEQ-8). MATERIALS AND METHODS: The translation-retro-translation method was applied to the CLDEQ-8 questionnaire. Two independent native Spanish-speaking translators adapted the questionnaire from English to Spanish, and then a committee of experienced clinicians (CE) evaluated the semantic equivalence and designed a Spanish version of the CLDEQ-8 questionnaire. The resulting translated version was tested conducting a pilot study in contact lens users and assessing their perception and overall understanding of the terminology. The results were analyzed and a final version was designed. The final version was retro-translated to English by a native English-speaking translator and compared with the original CLDEQ-8 version to confirm there were no meaningful differences. To clinically validate the new instrument, a prospective study was conducted to apply the new Spanish CLDEQ-8 to 50 contact lens users. RESULTS: Fifty patients were studied with an average age of 21.50 ± 1.66 years. The average CLDEQ-8 score was 13.28 ± 6.81 points (range 1-31). The internal consistency (Cronbach's alpha) was 0.89, with a corrected index of homogeneity >0.50 for all evaluated items. CONCLUSIONS: The process of trans-cultural adaptation of the questionnaire CLDEQ-8 resulted in the elaboration of a reliable and much needed instrument capable of measuring frequency and intensity of dry eye symptoms in Spanish-speaking contact lens users.

Indications and outcomes of pediatric keratoplasty in a tertiary eye care center: A retrospective review.

To evaluate indications and outcomes of pediatric keratoplasty in a tertiary eye center, and identify factors that affect visual outcomes.We performed a retrospective review of penetrating keratoplasty in children aged 0 to 18 years between 1995 and 2011 in the Asociación para Evitar la Ceguera en México IAP, Hospital "Dr. Luis Sánchez Bulnes".A total of 574 penetrating keratoplasties were performed during the study interval. Median follow-up was 5.0 years. Main indications included keratoconus (55.58%), postherpetic scarring (9.58%), traumatic opacities (7.49%), and bullous keratopathy (6.09%). Rejection rates at 5 years were 27% overall, and among indications, keratoconus showed the best graft survival at 60-months follow-up (85%). The percentage of patients with best corrected visual acuity (BCVA) posttransplant >20/400 at 5 years in the nonrejection group was 81.25% and 82.74% in < and > 10 years of age (YOA) groups, respectively, versus a BCVA posttransplant > 20/400 at 5 years in the rejection group of 53.68% and 51.72% in < and > 10 YOA groups, respectively. There was a statistically significant reduced rejection rate between genders at 18 months of follow-up, favoring males.Despite being considered a high-risk procedure in children, penetrating keratoplasty can achieve good results, especially in patients with keratoconus. It can achieve significative improvements of visual acuity, provided there is an adequate follow-up and treatment adherence.

Weighing of risk factors for penetrating keratoplasty graft failure: application of Risk Score System.

AIM: To analyze the relationship between the score obtained in the Risk Score System (RSS) proposed by Hicks et al with penetrating keratoplasty (PKP) graft failure at 1y postoperatively and among each factor in the RSS with the risk of PKP graft failure using univariate and multivariate analysis. METHODS: The retrospective cohort study had 152 PKPs from 152 patients. Eighteen cases were excluded from our study due to primary failure (10 cases), incomplete medical notes (5 cases) and follow-up less than 1y (3 cases). We included 134 PKPs from 134 patients stratified by preoperative risk score. Spearman coefficient was calculated for the relationship between the score obtained and risk of failure at 1y. Univariate and multivariate analysis were calculated for the impact of every single risk factor included in the RSS over graft failure at 1y. RESULTS: Spearman coefficient showed statistically significant correlation between the score in the RSS and graft failure (P<0.05). Multivariate logistic regression analysis showed no statistically significant relationship (P>0.05) between diagnosis and lens status with graft failure. The relationship between the other risk factors studied and graft failure was significant (P<0.05), although the results for previous grafts and graft failure was unreliable. None of our patients had previous blood transfusion, thus, it had no impact. CONCLUSION: After the application of multivariate analysis techniques, some risk factors do not show the expected impact over graft failure at 1y.

Prevalencia de síntomas de enfermedad de la superficie ocular en pacientes que acuden a consulta oftalmológica.

OBJECTIVE: To determine the prevalence of symptoms of ocular surface disease (OSDI) surface disease and its relationship with associated risk factors in patients of ophthalmic practices using OSDI questionnaire. METHOD: A cross-sectional survey was conducted Between September and December 2014 to assess the prevalence and risk factors for OSDI. RESULTS: The OSDI average value was 40.46 ± 23.62 points, with 86.4% of patients (1967) having a OSDI score higher than 12 points. Women had OSDI symptoms more frequently than men (odds ratio: 1.17; 95% confidence interval: 1.08-1.28) and higher OSDI score (42.12 ± 24.03 vs. 38.01 ± 22.81 points). Patients without disease were younger than the patients with severe disease (45.30 ± 18.32 vs. 50.62 ± 18.86). CONCLUSIONS: Ophthalmological patients have a prevalence of 80.4% of OSDI. Female and older age was associated with ocular surface disease.

Frequency and risk factors associated with dry eye in patients attending a tertiary care ophthalmology center in Mexico City.

PURPOSE: The purpose of this study was to ascertain the frequency and risk factors of dry eye (DE) among patients attending a tertiary care ophthalmology center in Mexico. METHODS: Approximately 338 consecutive new patients attending a tertiary care ophthalmology center in Mexico City underwent an ocular surface examination, which included tear film break-up time, fluorescein corneal staining, Schirmer's test, and evaluation of meibum quality. Symptoms of DE were evaluated by the Ocular Surface Disease Index and Dry Eye Questionnaire-5. Information on demographics, exposures, past medical and ocular history, and medications was also collected. RESULTS: The frequency of severe DE symptoms was found to be 43% based on the Ocular Surface Disease Index and 30% based on Dry Eye Questionnaire-5. Risk factors significantly associated with increased DE symptoms included dry mouth and gastrointestinal ulcer medications. With regard to signs, aqueous tear deficiency was a less-frequent finding (22%) in our population than evaporative deficiency (94%). Risk factors associated with aqueous tear deficiency were dry mouth and diuretic use. No risk factors were associated with evaporative deficiency. Risk factors associated with meibomian gland dysfunction included old age, male sex, arthritis, and use of an antihypertensive. The only risk factor associated with corneal staining was dry mouth. CONCLUSION: This is the first study to demonstrate the frequency of symptomatic and clinical DE in a tertiary care ophthalmology center in Mexico. The frequency of DE ranged from 30% using a symptomatic definition to 94% using objective measures. Different risk factors were found for different aspects of DE, suggesting differing underlying pathophysiologies behind different DE subtypes.

Our experience after 1765 intravitreal injections of bevacizumab: the importance of being part of a developing story.

This retrospective report describes our 20 months'experience using intravitreal injections of bevacizumab for the treatment of several retinal diseases. We describe our experience after 1765 intravitreal injections of bevacizumab in the treatment of different proliferative retinopathies - retinopathy of prematurity, choroidal neovascularization, diabetic retinopathy, among others. We believe that the findings reported in this study move us closer to a better treatment for different pathologies. However, further studies need to be performed in order to determine the safety and long-term efficacy of intravitreal bevacizumab either as first line therapy, after failure of conventional therapy, or in combination with conventional therapy.

Confocal microscopy of corneal flap microfolds after LASIK.

PURPOSE: To describe the morphological characteristics of microfolds that appear at the corneal flap after LASIK, as seen under confocal microscopy. METHODS: Twenty-one eyes that had undergone LASIK were examined, all within 3 weeks to 1 month after surgery. A central scan of the total corneal thickness was obtained by using confocal microscopy in vivo. Confocal images were captured and digitized. The longitudinal orientation (vertical, horizontal, and oblique) and morphological characteristics of the microfolds were described and recorded. RESULTS: Six eyes had folds at the central corneal flap, visible as linear distortions in the confocal images: one fold had a vertical orientation, two were horizontal, and three were oblique. The folds were visible from the epithelial basal cell layer to the stromal portion of the flap and were deeper than Bowman's layer. CONCLUSIONS: Confocal microscopy allowed visualization of microfolds after LASIK. With the appropriate software, it is possible to analyze the morphological characteristics of these folds. Flap microfolds after LASIK are deeper than Bowman's layer.

Occupational corneal argyrosis in art silver solderers.

PURPOSE: To determine the value of confocal and specular microscopy in the examination of corneal argyrosis in art silver solderers. METHODS: Six patients with corneal argyrosis underwent a complete physical and ophthalmologic examination. Specular microscopy was performed in three cases, and in vivo confocal microscopy in four cases. Ultrasound biomicroscopy and corneal topography were performed in three cases. A conjunctival specimen of one patient was examined histologically in paraffin sections. RESULTS: Slit-lamp examination showed gray, diffuse opacities in the deep corneal stroma. Confocal microscopy showed highly reflective deposits with a granular pattern anterior to the corneal endothelium and hypereflective keratocyte nuclei with visible cytoplasm in the anterior stroma. Specular microscopy demonstrated round white bodies anterior to the corneal endothelium. Silver deposits were not found histologically. CONCLUSIONS: Silver solderers with long-term exposure to silver compounds are at high risk of developing corneal argyrosis. We conclude that specular microscopy and in vivo confocal microscopy provided important information for the diagnosis of corneal argyrosis.

A corneal diffuse neurofibroma as a manifestation of von recklinghausen disease.

PURPOSE: To report a case of a primary corneal diffuse neurofibroma in a patient with von Recklinghausen disease (NF-1). METHODS: Case report. A physical examination and histopathology were performed. The immunohistochemical studies were performed using an avidin-biotin-peroxidase complex technique on formalin-fixed and paraffin-embedded tissue. Histologic sections from corneal tissue were incubated with primary antibodies against vimentin and S-100 protein. A complementary ultrastructural study of the same formalin-fixed and paraffin-embedded tissue was made. RESULTS: The ophthalmologic examination revealed a yellowish-white elevated mass that involved the supratemporal cornea but not the limbus. Histologic study showed a tumor of the peripheral nerve sheath, a diffuse neurofibroma in the corneal stroma, and proliferation of spindle cells with markedly elongated nuclei. Cells comprising the tumor reacted with vimentin and S-100 protein, and the ultrastructural studies revealed myelinated nerve fibers confirming the diagnosis. CONCLUSION: The development of a primary diffuse neurofibroma in the cornea of patients with von Recklinghausen disease is possible. The present case supports the statement that neurofibromas arising from the peripheral nerve sheath may involve any part of the body.

Cambios en el estroma corneal in vivo secundarios a quemadura por álcali / In vivo corneal stroma changes secondary to alkali burn

Objetivo: Observar y describir, mediante microscopía confocal, los cambios asociados al proceso de cicatrización de quemadura por álcali, en córneas sanas de conejo. Método: Se realizó microscopía confocal (ConfoScan 2.0, Fortune Technologies Srl.,Italy) para el análisis morfológico del proceso de cicatrización corneal secundaria a quemadura por álcali, previo a la quemadura, a la semana, al mes y a los tres meses. Resultados: Se observó una cicatriz subepitelial cuya densidad aumenta al profundizar al estroma anterior, desde la primer semana hasta 3 meses después. El epitelio se encontró re-epitelizado desde la primer semana a la quemadura por álcali. Conclusiones: La microscopía confocal demuestra la pronta recuperación del epitelio corneal de los conejos, no obstante se requiere de un estudio a mayor largo plazo para determinar si existen cambios en el proceso de cicatrización del estroma corneal.

Microscopia confocal de la córnea / Confocal microscopy of the cornea

Objetivo: Analizar las estructuras celulares corneales mediante microscopia confocal en córneas aparentemente sanas. Método: Se realizó microscopia confocal (ConfoScan 2.0, Fortune Tecnologies Srl., Italy) para el análisis morfológico de las diferentes estructuras corneales, in vivo, de manera no invasiva y en tiempo real a 10 córneas. Resultados: Se observó el epitelio superficial, las células basales epiteliales, el plexo nervioso subepitelial, el estroma y el endotelio corneal. Conclusiones: Hemos demostrado la utilidad del microscopio confocal para observar y analizar la población celular corneal, lo cual tiene un papel potencial en la valoración de los cambios dinámicos y estructurales de importancia en el diagnóstico y evaluación del paciente.