El trasplante de córnea en Villa Clara: diez años transcurridos de la primera intervención quirúrgica / Corneal transplantation in Villa Clara: after ten years the first surgical intervention

Introducción: La córnea constituye el elemento más importante del sistema óptico, al ser el primer medio transparente del ojo; tiene la finalidad de mejorar la calidad de la imagen que se forma en la retina, por lo que su transparencia es imprescindible para poder obtener una buena agudeza visual. Cuando sus capas están afectadas por diferentes enfermedades, se requiere sustituir este tejido dañado; este procedimiento, denominado trasplante de córnea o queratoplastia, tiene diferentes finalidades. Objetivo: Caracterizar los resultados de la cirugía de trasplante de córnea tras diez años del primer procedimiento quirúrgico en la provincia de Villa Clara. Métodos: Se realizó un estudio observacional descriptivo longitudinal retrospectivo, con una muestra de 204 pacientes operados de trasplante de córnea en el Hospital Universitario Clínico-Quirúrgico «Arnaldo Milián Castro» de Villa Clara, en el período comprendido entre 2008 y 2018. Las variables estudiadas fueron: sexo, finalidad del procedimiento, diagnóstico y complicaciones. Resultados: Predominó el sexo masculino (53,4 %); la finalidad más frecuente del trasplante tuvo fines ópticos (85,8 %); principal diagnóstico: la queratopatía bullosa (42,7 %); dentro de las complicaciones más frecuentes estuvieron: el rechazo al injerto, el defecto epitelial y el glaucoma secundario. Conclusiones: La cirugía de trasplante de córnea en la provincia de Villa Clara significa un gran avance en el desarrollo y perfeccionamiento para el tratamiento de múltiples afecciones corneales. Los diagnósticos más frecuentes fueron: la queratopatía bullosa y las opacidades corneales; las complicaciones más frecuentes, el rechazo al injerto, la aparición de defectos epiteliales y el glaucoma secundario.

Introduction: the cornea constitutes the most important element of the optical system, being the first transparent medium of the eye; its purpose is to improve the quality of the image that is formed on the retina, so its transparency is essential to obtain good visual acuity. When its layers are affected by different diseases, it is required to replace this damaged tissue; this procedure called cornea transplant or keratoplasty has different purposes. Objective: to characterize the results of corneal transplant surgery ten years after the first surgical procedure in Villa Clara province. Methods: a retrospective, longitudinal, descriptive and observational study was carried out with a sample of 204 patients who underwent corneal transplant surgery at "Arnaldo Milián Castro" Clinical and Surgical University Hospital in Villa Clara between 2008 and 2018. Age, purpose of the procedure, diagnosis and complications were the variables studied. Results: male gender predominated (53.4%); the most frequent purpose of the transplant was for optical purposes (85.8%); bullous keratopathy (42.7%) was the main diagnosis as well as, graft rejection, epithelial defect and secondary glaucoma were among the most frequent complications. Conclusions: corneal transplant surgery in Villa Clara province means a great advance in the development and improvement for the treatment of multiple corneal conditions. The most frequent diagnoses were bullous keratopathy and corneal opacities; graft rejection, the appearance of epithelial defects and secondary glaucoma were the most frequent complications.

Corrective effect of femtosecond laser assisted laser in situ keratomileusis Xtra on patients with moderate to high myopia after 2a postoperatively / 国际眼科杂志(Guoji Yanke Zazhi)

AIM:To evaluate corrective effect and stability of corneal morphology in patients with moderate to high myopia after 2a treatment of femtosecond laser assisted laser in situ keratomileusis(FS-LASIK)Xtra.METHODS:Retrospective case-control study. A total of 30 cases(58 eyes)Patients with moderate to high myopia combined with astigmatism who planned to undergo refractive surgery in our hospital from August 2019 to August 2020 were included, and different types of surgery were performed respectively based on the relevant index of keratoconus screening in the preoperative corneal topography. They were divided into FS-LASIK group and Xtra group, with 15 cases(29 eyes)in each group. Uncorrected visual acuity(UCVA), best corrected visual acuity(BCVA), spherical equivalent(SE)and the corneal curvature of the anterior and posterior surfaces of different diameters(3, 5 and 7 mm)measured by Sirius three-dimensional corneal topography were observed preoperatively and 3 mo, 1 and 2 a postoperatively.RESULTS: The UCVA of the two groups of patients at different time points after surgery was significantly increased compared with preoperatively(both P<0.01), and there was no difference in UCVA and SE between the two groups(P>0.05). After 2 a postoperatively, residual astigmatism was -0.25-0 D in 25 eyes(86%)of the FS-LASIK Xtra group and 24 eyes(83%)of the FS-LASIK group. The actual corrected SE and expected corrected SE of both groups were positively correlated(both P<0.05). There were differences in corneal curvature on the surface of different diameter areas(3, 5, and 7 mm)between the two groups at 3 mo, 1, and 2 a postoperatively compared with preoperatively. After 1 and 2 a postoperatively, the corneal posterior surface curvature of the FS-LASIK Xtra group with corneal diameter of 3 and 5 mm was higher than that of the FS-LASIK group(P<0.05).CONCLUSIONS:FS-LASIK Xtra has good safety, efficacy and predictability in correcting patients with moderate to high myopia.

Accuracy of the ratio of axial length to corneal radius in the assessment of myopia in children and adolescents / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To explore the accuracy of the ratio of axial length(AL)to the average corneal radius(CR)(AL/CR value, i.e., axial ratio)in assessing myopia in children and adolescents.METHOD:Cross-sectional study. A total of 340 cases(680 eyes)of children and adolescents aged 4-16 years old were collected from the ophthalmology clinic of Shangyu People's Hospital of Shaoxing between January 2022 and October 2022. All patients were subjected to optometry after cycloplegia to obtain spherical equivalent(SE), check and record the patient's AL, average CR, and calculate the AL/CR value.RESULTS:All subjects in this study underwent optometry after cycloplegia, and a total of 609 eyes(89.6%)were found to have myopia(SE≤-0.50 D), 58 eyes(8.5%)with hyperopia(SE≥+0.50 D)and 13 eyes(1.9%)with emmetropia(-0.50 D>SE>+0.50 D). There was a statistically significant difference in SE, AL and AL/CR values among different refractive states(P<0.01), but there was no difference in CR(P>0.05). All subjects have refractive parameters: SE +8.75--8.75(average -2.25±2.38)D; AL 19.91-27.54(average 24.41±1.22)mm; CR 7.17-8.71(average 7.83±0.27); AL/CR values range from 2.50-3.50(average 3.12±0.14), correlation analysis showed a relative strong negative correlation between SE and AL/CR and AL(r=-0.891, P<0.01; r=-0.758, P<0.01), but no significant correlation between SE and CR(r=0.067, P>0.05), there was a positive correlation between AL and CR(r=0.483, P<0.01). The linear relationships between SE and AL/CR, AL were SE=45.026-15.162×AL/CR, R2=0.794, SE=33.741-1.474×AL, R2=0.574, respectively. The gold standard was based on the optometric results of cycloplegia, the sensitivity, specificity, misdiagnosis rate and missed diagnosis rate of AL/CR value for myopia were 0.962, 0.839, 0.169, 0.038, respectively, and the accuracy was 94.85%, the Kappa coefficient was 0.742, and the area under the ROC curve was 0.972.CONCLUSION:With high qualitative diagnostic value for myopia and a certain clinical significance for myopia monitoring, AL/CR value can be used to guide myopia prevention and control and other related ophthalmic clinical work.

Research progress on the stress-strain index of Corvis ST / 国际眼科杂志(Guoji Yanke Zazhi)

Corneal visualization Scheimpflug technology(Corvis ST)is currently the most commonly used clinical device for assessing in vivo corneal biomechanics. The new parameter stress-strain index(SSI)has been a hot topic of clinical research in recent years, which not only directly reflect corneal biomaterial stiffness, but also closely correlates with the progression of certain diseases. SSI was generated based on the predictions of corneal behavior using finite element(FE)numerical modeling to simulate the effects of intraocular pressure and Corvis ST jets. The SSI algorithm does not change with central corneal thickness(CCT), intraocular pressure, or biomechanically corrected intraocular pressure(BIOP), but it is clearly associated with altered collagen fibres in the corneosclera. The principles of SSI, the relationship between age and SSI, the relationship between axial length and SSI, the relationship between myopia and SSI, and the application of SSI are summarized and concluded.

Research progress of clinical application and complication of contact lens in keratoconus / 国际眼科杂志(Guoji Yanke Zazhi)

Keratoconus is a progressive blinding eye disease that characterized by corneal thinning and protrusion, which accompanied with irregular astigmatism and impaired visual acuity.The irregular astigmatism of early keratoconus can be corrected by spectacles. For the irregular astigmatism of moderate to severe keratoconus, spectacles are no longer suitable, and contact lenses are the best choice for patients to restore vision. There are various types of contact lenses, making the selection very difficult. In addition, trying on lenses for a long time will increase the discomfort and overall feeling of patients, and greatly increase the workload of doctors. Thus, the article aims to summarize and discuss the classification of contact lenses, the application of contact lenses in different types of keratoconus, the complications of contact lens, and the current status and prospect of contact lenses, with a view to understanding the management and clinical application of contact lenses in keratoconus patients and to further improving the application value of contact lenses in keratoconus.

Research progress in the diagnosis and treatment of neurotrophic keratitis / 国际眼科杂志(Guoji Yanke Zazhi)

Neurotrophic keratitis(NK)is a degenerative corneal disease caused by impairment of trigeminal innervations. It can lead to spontaneous corneal epithelial defects, corneal ulceration and perforation. Early diagnosis of NK is crucial and requires accurate investigation of clinical history and thorough examination of ocular surface to determine clinical stage. Treatment for NK needs to be divided into stages according to disease severity. In addition to conventional treatments including artificial tears, blepharorrhaphy, and amniotic membrane transplantation, there are also emerging treatments such as targeted drug therapy and corneal neurotization. This article summarized the epidemiology, clinical manifestations and classification, etiology, diagnosis, differential diagnosis and treatment of NK, aiming to provide reference for the early diagnosis and treatment of NK in the future.

Potential of human induced pluripotent stem cells differentiating into corneal epithelial cells in simulated limbal stem cell microenvironment / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To investigate the potential of human induced pluripotent stem cells(hiPSCs)differentiating into corneal epithelial cells in the simulated limbal stem cells(LSCs)microenvironment.METHODS: The hiPSC cell lines were established in vitro, and hiPSCs were co-cultured with corneal stromal cells in transwell system, which simulated the LSC microenvironment. Bone morphogenetic protein 4(BMP4)and a specific transforming growth factor β inhibitor(SB431542)were added to improve the differentiation efficacy. The expression of corneal epithelial cell-specific markers CK3 and CK12, corneal epithelial cell precursor CK15, and the limbal stem cell markers ABCG5 were determined by immunofluorescence staining and flow cytometry.RESULTS: The hiPSCs were actively proliferated in vitro, and immunofluorescence staining showed positive stem cell-specific markers OCT4, SOX2, TRA-1-60 and NANOG. Furthermore, hiPSCs co-cultured with corneal stromal cells exhibited LSCs markers ABCG5 and corneal epithelial cell precursor markers CK15 were positive; however, corneal epithelial cell markers CK3 and CK12 were negative. With the addition of BMP4 and SB431542, hiPSCs showed positive expression of CK3, and the CK3 expression increased over the time.CONCLUSION: With the addition of SB431542 and BMP4, hiPSCs cultured in simulated LSCs microenvironment could differentiate into corneal epithelial cells.

Manually prepared lamellae for Descemet stripping endothelial keratoplasty (Pachy-DSEK): comparison of four dissection depths / Lamelas manualmente dissecadas para transplante endotelial de córnea (Pachy-DSEK): comparação entre quatro profundidades de dissecção

ABSTRACT Purpose: This study aimed to compare four depths of manual dissection for the preparation of Descemet stripping endothelial keratoplasty lamellae. Methods: Eye bank corneas were randomized into four groups according to dissection depths: Pachy-100 (incision depth = central corneal thickness-safety margin of 100 µm), Pachy-50 (safety margin of 50 µm), Pachy-0 (no safety margin), and Pachy+50 (incision depth = central corneal thickness + 50 µm). All endothelial lamellae were prepared using a standardized method of manual dissection (Pachy-DSEK). The central, paracentral (3.0-mm zone), and peripheral (6.0-mm zone) lamella thicknesses and incision depths were measured by optical coherence tomography. The 3.0-mm and 6.0-mm zone central-to-peripheral thickness ratios were calculated. Results: Endothelial perforation occurred only in the Pachy+50 group (n=3, 30%). Central lamella's thickness in Pachy-100, Pachy-50, Pachy-0, and Pachy+50 groups measured 185 ± 42 µm, 122 ± 29 µm, 114 ± 29 µm, and 58 ± 31 µm, respectively (p<0.001). The overall 3.0- and 6.0-mm C/P ratios were 0.97 ± 0.06 and 0.92 ± 0.14, respectively. Preoperative donor characteristics were not correlated with most thickness outcomes. The planned incision depth correlated significantly with most lamella's thickness parameters (p<0.001). The overall thickness of the lamella negatively correlated with the planned incision depth (p<0.001, r=-0.580). The best outcome was found in the Pachy-0 group, as 75% of the lamellae measured <130 µm and there was no endothelial perforation. Conclusions: By using a standardized method of dissection, most manually prepared lamellae presented a planar shape. Setting the incision depth to the central corneal thickness did not result in endothelial perforation and a high percentage of ultrathin lamellae was achieved.

RESUMO Objetivo: Comparar quatro profundidades de dissecção manual usadas no preparo de lamelas para transplante endotelial. Métodos: Córneas humanas de treinamento disponibilizadas foram randomizadas em quatro grupos: Pachy-100 (profundidade de incisão = espessura corneana central - margem de segurança de 100 µm), Pachy-50 (margem de segurança de 50 µm), Pachy-0 (sem margem de segurança) e Pachy+50 (profundidade de incisão = espessura corneana central + 50 µm). Todas as lamelas foram dissecadas através um método padronizado e já publicado (Pachy-DSEK). As espessuras das lamelas (centro, zona de 3,0mm e zona de 6,0mm) foram medidas com tomografia de coerência óptica. A razão de espessura centro-periferia foi calculada aos 3,0 e 6,0 mm de diâmetro. Resultados: Perfuração endotelial ocorreu apenas no grupo Pachy+50 (n=3, 30%). A espessura central da lamela nos grupos Pachy-100, Pachy-50, Pachy-0 e Pachy+50 foi de 185 ± 42 µm, 122 ± 29 µm, 114 ± 29 µm, e 58 ± 31 µm, respectivamente (p<0,001). As razões C/P aos 3,0 e 6,0 mm foram de 0,97 ± 0,06 e 0,92 ± 0,14, respectivamente. Os parâmetros de características do doador não se correlacionaram com os resultados de espessura de lamela. A profundidade planejada de incisão se correlacionou com a maioria dos parâmetros de espessura de lamela (p<0,001). A espessura de lamela se correlacionou negativamente com a profundidade planejada da incisão (p<0.001, r=-0,580). O melhor resultado foi observado no grupo Pachy-0, em que 75% das lamelas mediram abaixo de 130 µm e não houve perfuração endotelial. Conclusão: Através de um método padronizado de dissecção, a maioria das lamelas endoteliais apresentou uma configuração planar. O planejamento de profundidade de incisão igual à espessura corneana central resultou em alta porcentagem de lamelas ultrafinas sem ocorrência de perfuração.

Mycobacterium abscessus keratitis after LASIK surgery / Ceratite por Mycobacterium abscessus após cirurgia LASIK

ABSTRACT A 33-year-old male presented with unilateral subacute infectious keratitis 4 weeks after surgery. Corneal inflammation was resistant to standard topical antibiotic regimens. During diagnostic flap lifting and sampling, the corneal flap melted and separated. Through flap lifting, corneal scraping, microbiological diagnosis of atypical mycobacteria, and treatment with topical fortified amikacin, clarithromycin, and systemic clarithromycin, clinical improvement was achieved.

RESUMO Paciente do sexo masculino, 33 anos, apresentou ceratite infecciosa subaguda unilateral 4 semanas após a cirurgia. A inflamação da córnea foi resistente aos regimes de antibióticos tópicos padrão. A aba da córnea foi derretida e seccionada durante o levantamento e amostragem para diagnóstico. A melhora clínica só foi alcançada após levantamento do retalho, raspagem e diagnóstico microbiológico de micobactérias atípicas e tratamento com amicacina fortificada tópica, claritromicina e claritromicina sistêmica.

Descemet's membrane endothelial keratoplasty for primary graft failure after penetrating keratoplasty / Transplante endotelial de membrana de Descemet para falência primária após transplante penetrante

ABSTRACT Primary graft failure (PGF) is a known complication following penetrating keratoplasty (PKP). The usual approach to treat this complication is to repeat a penetrating keratoplasty. Here, we report a case of Descemet's membrane endothelial keratoplasty (DMEK) for the treatment of PGF after PKP. A patient that underwent PKP, developed PGF with persistent graft edema and very poor visual acuity despite aggressive steroid use and a proof anti-viral treatment. Three months after the initial surgery, a DMEK was performed under the PKP graft. There was progressive early corneal clearing and, by the end of the first month, the patient already had no corneal edema. Uncorrected visual acuity (UCVA) improved to 20/40 and best corrected visual acuity (BCVA) to 20/20. DMEK may be an alternative to a second PKP for the treatment of PGF. This technique is a less invasive option when compared to the standard PKP procedure.

RESUMO A falência primária do enxerto é uma complicação conhecida que pode ocorrer após o transplante penetrante de córnea. O tratamento usual dessa complicação é com um novo transplante penetrante. Apresentamos um caso em que foi usado o transplante endotelial de membrana de Descemet (DMEK - do inglês Descemet membrane endo-thelial keratoplasty) para o tratamento da falência primária após o transplante penetrante. Uma paciente submetida a transplante penetrante evoluiu com falência primária do enxerto a despeito do uso intenso de corticoide tópico e uma prova terapêutica de antivirais. Três meses após a cirurgia inicial, foi optado pela realização do transplante endotelial de membrana de Descemet sob o transplante penetrante. Houve um clareamento precoce e progressivo do enxerto com melhora importante da visão. Após um mês, a visão sem correção era de 20/40 melhorando para 20/20 com refração. O transplante endotelial de membrana de Descemet pode ser uma alternativa a um novo transplante penetrante como tratamento da falência primária.

Evaluation of unilateral corneal collagen cross-linking on fellow untreated eyes of patients with keratoconus / A avaliação da reticulação unilateral do colágeno corneano em olhos não tratados de pacientes com ceratocone

ABSTRACT Purpose: This study aimed to examine the effects of unilateral corneal collagen cross-linking treatment on visual acuity and the topographic findings of the fellow untreated eye of patients who had bilateral progressive keratoconus. Methods: Patients with progressive keratoconus who underwent cross-linking treatment were screened retrospectively. A total of 188 untreated eyes of 188 patients whose eyes were treated unilaterally with either standard or accelerated cross-linking and refused cross-linking procedure for the fellow eye were included. Visual acuity and topographic findings of the fellow untreated eyes were obtained preoperatively and postoperatively at the 1st, 3rd, 6th, 12th, 24th, 30th, and 36th months. Results: The change over time of variables examined was similar in the untreated eyes of patients who received standard and accelerated cross-linking methods (p>0.05). At the 12th month, 136 (95.8%) untreated eyes were stable according to progression criteria. Only 4 (8%) eyes were progressive at the 24th month. No progression was observed in any of the 16 patients with a 36-month follow up. Conclusions: The results showed that the fellow untreated eyes of patients with bilateral progressive keratoconus did not have significant progression rates after unilateral cross-linking treatment.

RESUMO Objetivo: Examinar os efeitos do tratamento de reticulação unilateral do colágeno corneano na acuidade visual e os achados topográficos em olhos não tratados de pacientes com ceratocone progressivo bilateral. Métodos: Foram rastreados retrospectivamente pacientes com ceratocone progressivo submetidos a tratamento de reticulação. Foram incluídos no estudo 188 olhos não tratados de 188 pacientes tratado unilateralmente com reticulação padrão ou acelerada e que recusaram o procedimento de reticulação no outro olho. A acuidade visual e os achados topográficos dos olhos não tratados foram obtidos no pré- e pós-operatório no 1º, 3º, 6º, 12º, 24º, 30º e 36º mês. Resultados: As alterações ao longo do tempo foram semelhantes para as variáveis examinadas nos olhos não tratados de pacientes tratados com métodos de reticulação padrão e acelerado (p>0,05). No 12º mês, 136 olhos não tratados (95,8%) estavam estáveis, de acordo com os critérios de progressão. Apenas quatro olhos (8%) mostraram progressão no 24º mês. Nenhuma progressão foi observada nos 16 pacientes que tiveram um acompanhamento de 36 meses. Conclusões: O estudo mostrou que os olhos não tratados de pacientes com ceratocone progressivo bilateral não apresentaram taxas de progressão significativas após o tratamento unilateral com reticulação.

Corneal reshaping: an experiment with a type I collagen-based vitrigel for remodeling porcine corneas / Remodelamento corneano: relato de um experimento com um vitrigel a base de colágeno tipo I para remodelamento de córneas porcinas

ABSTRACT Purpose: This study aimed to report an experiment designed to determine anatomical changes in porcine corneas following placement of a novel polymer implant into the cornea. Methods: An ex vivo porcine eye model was used. A novel type I collagen-based vitrigel implant (6 mm in diameter) was shaped with an excimer laser on the posterior surface to create three planoconcave shapes. Implants were inserted into a manually dissected stromal pocket at a depth of approximately 200 μm. Three treatment groups were defined: group A (n=3), maximal ablation depth 70 μm; Group B (n=3), maximal ablation depth 64 μm; and group C (n=3), maximal ablation depth 104 μm, with a central hole. A control group (D, n=3) was included, in which a stromal pocket was created but biomaterial was not inserted. Eyes were evaluated by optical coherence tomography (OCT) and corneal tomography. Results: Corneal tomography showed a trend for a decreased mean keratometry in all four groups. Optical coherence tomography showed corneas with implants placed within the anterior stroma and visible flattening, whereas the corneas in the control group did not qualitatively change shape. Conclusions: The novel planoconcave biomaterial implant described herein could reshape the cornea in an ex vivo model, resulting in the flattening of the cornea. Further studies are needed using in vivo animal models to confirm such findings.

RESUMO Objetivo: Relatar um experimento projetado para determinar alterações anatômicas em córneas porcinas após a colocação de um novo implante de polímero na córnea. Métodos: Foi utilizado olho de porco ex vivo. Um novo agente modelador biocompatível, de colágeno tipo 1, com 6mm de diâmetro foi moldado com excimer laser em sua face posterior, para criar três formatos planocôncavos. Os implantes foram inseridos dentro de um bolsão, dissecado manualmente, a 200 micrômetros (μm). Foram definidos três grupos de tratamento: grupo A (n=3), teve a profundidade máxima de ablação de 70 μm; o grupo B (n=3), profundidade máxima de ablação de 64 μm; e o grupo C (n=3), profundidade máxima de ablação de 104 μm, com buraco central. O grupo controle, D (n=3), foi incluído, com a criação do bolsão estromal, porém sem inserir o material. A avaliação desses olhos foi realizada por tomografia de coerência óptica (OCT) e por tomografia corneana. Resultados: A tomografia corneana mostrou uma tendência para diminuição da ceratometria média em todos os 4 grupos. A tomografia de coerência óptica mostrou córneas com implantes localizados no estroma anterior e aplanamento visível, enquanto as córneas não mudaram qualitativamente o formato no grupo controle. Conclusões: O novo implante de biomaterial planocôncavo descrito aqui foi capaz de remodelar a córnea em modelo de animal ex vivo, resultando no aplanamento corneano. Novos estudos são necessários usando modelos animais in vivo para confirmar tais achados.

Microbial keratitis in Sao Paulo, Brazil: a 10-year review of laboratory results, epidemiological features, and risk factors / Ceratite microbiana em São Paulo, Brasil: uma revisão de 10 anos dos resultados de laboratório, características epidemiológicas e fatores de risco

ABSTRACT Purpose: To study epidemiological data, laboratory results, and risk factors associated with microbial keratitis. Methods: We conducted a retrospective study of corneal sample cultures from patients with microbial keratitis from January 2010 to December 2019. Results were analyzed according to the etiological diagnosis of bacterial, mycotic, or parasitic infection and were associated with related risk factors. Results: We analyzed 4810 corneal samples from 4047 patients (mean age 47.79 ± 20.68 years; male 53.27%). The prevalence of bacterial, fungal, and Acanthamoeba infections were 69.80%, 7.31%, and 3.51%, respectively. The most frequently isolated bacteria were coagulase-negative Staphylococcus (CoNS) (45.14%), S. aureus (10.02%), Pseudomonas spp. (8.80%), and Corynebacterium spp. (6.21%). Among CoNS, the main agent was S. epidermidis (n=665). For mycotic keratitis, Fusarium spp. (35.42%) and Candida parapsilosis (16.07%) were the most common agents among filamentous and yeasts isolates, respectively. Contact lens use was associated with a positive culture for Acanthamoeba spp. (OR = 19.04; p < 0.001) and Pseudomonas spp. (OR = 3.20; p < 0.001). Previous ocular trauma was associated with positive fungal cultures (OR = 1.80; p = 0.007), while older age was associated with positive bacterial culture (OR = 1.76; p = 0.001). Conclusions: Our findings demonstrated a higher positivity of corneal sample cultures for bacteria. Among those, CoNS was the most frequently identified, with S. epidermidis as the main agent. In fungal keratitis, Fusarium spp. was the most commonly isolated. Contact lens wearers had higher risks of positive cultures for Acanthamoeba spp. and Pseudomonas spp. Ocular trauma increased the risk of fungal infection, while older age increased the risk of bacterial infection.

RESUMO Objetivo: Estudar os dados epidemiológicos, resultados laboratoriais e fatores de risco associados às ceratites infecciosas. Métodos: Estudo retrospectivo das amostras de cultura de córnea em pacientes com ceratites infecciosas entre Janeiro/2010 a Dezembro/2019. Os resultados foram analisados de acordo com o diagnóstico etiológico de infecção bacteriana, fúngica ou parasitária e correlacionado com os fatores de risco relacionados. Resultados: Quatro mil, oitocentas e dez amostras corneanas de 4047 pacientes (média de idade de 47,79 ± 20,68 anos; homens em sua maioria (53,7%) foram incluídas. A prevalência de infecções por bactéria, fungo e Acanthamoeba foram de 69.80%, 7,31%, and 3,51%, respectivamente. A maioria das bactérias mais frequentemente isoladas foram Staphylococcus coagulase-negativo (CoNS) (45,14%), S. aureus (10,02%), Pseudomonas spp. (8,80%), e Corynebacterium spp. (6,21%). Dentre CoNS, o principal agente foi S. epidermidis (n = 665). Nas ceratites fúngicas, Fusarium spp. (35,42%) e Candida parapsilosis (16,07%) foram os agentes mais comuns entre os filamentosos e leveduriformes, respectivamente. O uso de lentes de contato foi associado à cultura positiva para Acanthamoeba spp. (OR = 19,04; p < 0,001) e Pseudomonas spp (OR = 3,20; p < 0,001). Trauma ocular prévio foi associado a culturas positivas para fungo (OR = 1,80; p = 0,007), e idade avançada foi associada a culturas positivas para bactéria (OR = 1,76; p = 0,001). Conclusões: Nossos achados demonstraram uma maior positividade para bactérias em amostras de cultura corneana. Dentre estas, CoNS foi mais frequentemente identificado, sendo S. epidermidis o principal agente. Nas ceratites fúngicas, Fusarium spp. Foi o mais comumente isolado. O risco de positividade para Acanthamoeba spp. e Pseudomonas spp. foi maior em usuários de lentes de contato. Trauma ocular aumentou o risco de cultura positiva para fungo, ao passo que idade mais avançada aumentou o risco de infecção bacteriana.

Keratitis in patients with corneal foreign bodies: a cross-sectional study in Cali, Colombia / Ceratite em pacientes com corpos estranhos na córnea: um estudo transversal em Cali, Colômbia

ABSTRACT Purposes: To describe the clinical characteristics and factors associated with keratitis in patients with corneal foreign bodies in Colombia. Methods: This cross-sectional study was based on a clinical records review of patients who had corneal foreign bodies and were admitted to the emergency department between June 2018 and June 2019 in Cali, Colombia. The primary outcome was the presence of keratitis diagnosed based on clinical criteria. Univariate and multivariate logistic regression models were used to identify associated factors. Results: A total of 381 corneal foreign bodies in 372 patients were analyzed (median age, 40.0; interquartile range, 29.0-53.0 years; male, 94.7% (n=352). Ninety-five patients developed keratitis (24.9%, 95% confidence interval [CI] 20.8%-29.5%). In the multivariate analysis, age 30 years (odds ratio [OR] 2.15, 95% CI 1.06-4.36), finding of aqueous flare (OR 2.81, 95% CI 1.39-5.66]), and a foreign body in the peripheral cornea (OR 2.05, 95% CI 1.19-3.50] were associated with an increased risk for keratitis. Sex, time between injury and admission, and corneal edema were not related to keratitis (p>0.05). Conclusion: In Cali, Colombia, a high proportion of keratitis was reported in patients with corneal foreign body. Age, an aqueous flare, and a foreign body in the peripheral cornea were the factors associated with keratitis.

RESUMO Objetivo: Descrever as características clínicas e os fatores associados à presença de ceratite em pacientes com corpos estranhos na córnea em uma população colombiana. Métodos: Trata-se de um estudo transversal baseado na revisão dos registros clínicos de pacientes com corpos estranhos na córnea admitidos em um departamento de emergência em Cali, Colômbia, entre junho de 2018 e junho de 2019. O desfecho primário foi a presença de ceratite diagnosticada através de critérios clínicos. Foram utilizados modelos de regressão logística univariada e multivariada para identificar os fatores associados. Resultado: Neste estudo, foi analisado um total de 381 corpos estranhos na córnea em 372 pacientes (idade média: 40,0 anos, intervalo interquartil: 29,0-53,0; sexo masculino: 94,7% [352 casos]). Noventa e cinco casos desenvolveram ceratite (24,9%, intervalo de confiança de 95% — IC 95%: 20,8%-29,5%). Na análise multivariada, para idade ≤30 anos (razão de chances — RC: 2,15, IC 95%: 1,06-4,36), o achado de flare aquoso (RC: 2,81, IC 95%: 1,39-5,66]) e a presença de corpo estranho na periferia da córnea (RC: 2,05, IC 95%: 1,19-3,50) foram associados a um risco aumentado de ceratite. Sexo, tempo entre a lesão e a internação, e edema da córnea não foram relacionados à ceratite (p>0,05). Conclusão: Há uma proporção elevada de ceratite em casos de corpos estranhos na córnea em Cali, Colômbia. Os três fatores associados à ceratite foram a idade, o achado de flare aquoso e a presença de corpo estranho na periferia da córnea.

Recusa familiar para doação de córneas para transplante: fatores associados e tendência / Negativa familiar para donación de córneas para trasplante: factores asociados y tendencia / Family refusal to donate a cornea for transplantation: associated factors and trends

Resumo Objetivo Analisar a recusa familiar de doação de córnea para transplante em uma Organização de Procura de Órgãos. Métodos Estudo quantitativo do tipo transversal sobre as recusas de córnea de doadores em situação de morte encefálica. A fonte de dados foi constituída pelos Termos de Autorização de Doação de Órgãos e Tecidos firmados entre janeiro de 2001 a dezembro de 2020 em uma Organização de Procura de Órgãos. Os dados foram coletados, tabulados e analisados de forma descritiva e inferencial. O presente estudo foi aprovado pelo Comitê de Ética em Pesquisa. Resultados Dos 2.447 Termos de Autorização de Doação de Órgãos e Tecidos firmados no período, 620 (25.34%) recusaram a doação de córneas. Com relação à tendência temporal de recusas de doação de córneas, o único período que apresentou significância foi de 2001 a 2009, quando as faixas etárias de zero a 11 anos e 12 a 19 anos demonstraram tendência decrescente, e a faixa etária maior ou igual a 60 anos, mostrou-se crescente. No período total de 2001 a 2020, as faixas etárias dos 20 a 40 anos, 41 a 59 anos e maior ou igual a 60 anos apresentaram, 48%, 59% e 73%, respectivamente, menores chances de recusa da doação de córneas. Conclusão A faixa etária apresentou associação com a recusa, tendo em vista que os indivíduos de maior idade apresentaram maiores índices.

Resumen Objetivo Analizar la negativa familiar de donación de córneas para trasplante en una Organización de Búsqueda de Órganos. Métodos: Estudio cuantitativo tipo transversal sobre la negativa de córnea de donantes en situación de muerte encefálica. La fuente de datos estuvo compuesta por los Términos de Autorización de Donación de Órganos y Tejidos firmados entre enero de 2001 y diciembre de 2020 en una Organización de Búsqueda de Órganos. Se recopilaron los datos, luego se tabularon y se analizaron de forma descriptiva e inferencial. El presente estudio fue aprobado por el Comité de Ética en Investigación. Resultados De los 2447 Términos de Autorización de Donación de Órganos y Tejidos firmados en el período, 620 (25,34 %) negaron la donación de córneas. Con relación a la tendencia temporal de negativas de donación de córneas, el único período que presentó significación fue de 2001 a 2009, cuando los grupos de edad de 0 a 11 años y de 12 a 19 años demostraron una tendencia decreciente, y el grupo de edad mayor o igual a 60 años se mostró creciente. En el período total de 2001 a 2020, los grupos de edad de 20 a 40 años, de 41 a 59 años y mayor o igual a 60 años presentaron un 48 %, un 59 % y un 73 %, respectivamente, menor probabilidad de negativa de donación de córneas. Conclusión El grupo de edad presentó relación con la negativa, considerando que los individuos de mayor edad presentan mayores índices.

Abstract Objective To analyze family refusals to donate a cornea for transplantation in an Organ Procurement Organization. Methods This was a quantitative cross-sectional study on corneal donation refusals from potential brain-dead donors. The data source was based on the Terms of Authorization for Donation of Organs and Tissues signed from January 2001 to December 2020 in an Organ Procurement Organization. Data were collected, tabulated, and analyzed in a descriptive and inferential manner. The present study was approved by the Research Ethics Committee. Results Of the 2,447 Terms of Authorization for Donation of Organs and Tissues signed in the above period, 620 (25.34%) of them refused to donate a cornea. Regarding the time trend of corneal donation refusals, the period 2001-2009 was the only one that showed significance, when the 0-11 and 12-19 age groups showed a decreasing trend and that of 60 years or older showed an increasing trend. In the period 2001-2020, the age groups of 20-40, 41-59, and 60 years or older had lower rates of refusal to donate a cornea (48%, 59%, and 73%, respectively). Conclusion The age group is associated with refusal because older individuals had the highest refusal rates.

Wet bio-amniotic membrane plugging combined with transplantation in the treatment of small corneal perforations

ABSTRACT Purpose: Wet bio-amniotic membrane plugging combined with transplantation is a novel option that combined amniotic membrane plugging with amniotic membrane transplantation for the treatment of small corneal perforations. This study aimed to evaluate the efficacy of wet bio-amniotic membrane plugging in the treatment of small corneal perforations and compared it with that of the penetrating keratoplasty procedure. Methods: Forty patients (41 eyes) with small corneal perforations <3 mm in diameter treated at our hospital between July 2018 and January 2021 were retrospectively included. Among them, 21 eyes were treated with wet bio-amniotic membrane plugging (wet bio-amniotic membrane plugging group), and 20 eyes were treated with penetrating keratoplasty procedure (penetrating keratoplasty procedure group). The best-corrected visual acuity, anterior chamber formation, corneal thickness, primary disease control, postoperative complications, and graft survival rate were assessed. Results: No significant difference in baseline characteristics was found between the wet bio-amniotic membrane plugging and penetrating keratoplasty procedure groups (p>0.05). The postoperative control rates of primary diseases in the wet bio-amniotic membrane plugging and penetrating keratoplasty procedure groups were 95.2% and 90.0%, respectively (p=0.481). Visual acuity was improved 6 months after the operation in the wet bio-amniotic membrane plugging group and was improved at postoperative 1 month in the penetrating keratoplasty procedure group. The formation time of the anterior chamber in the wet bio-amniotic membrane plugging group was significantly shorter than that in the penetrating keratoplasty procedure group (p=0.023). The corneal thickness of the two groups significantly increased 12 months after the operation; however, the degree of thickening in the penetrating keratoplasty procedure group was higher than that in the wet bio-amniotic membrane plugging group (p<0.001). During the follow-up, postoperative complications were not different between the two groups (p>0.999). Conclusion: The results suggest that wet bio-amniotic membrane plugging is effective and safe in the treatment of small corneal perforations. Thus, it can be used as an emergency treatment alternative to penetrating keratoplasty procedure for small corneal perforations.

Ultraviolet-A absorbance analysis in thin porcine corneas pre-and post-crosslinking

ABSTRACT Purpose: To determine the absorbance coefficient of the thin porcine cornea to ultraviolet-A radiation (365 nm) submitted for crosslinking. Methods: This in vitro, benchtop experiment using cadaver tissue study analyzed 12 porcine corneal lamellas, which were obtained using a microkeratome after mechanical de-epithelization and separated into three thickness groups: 180, 300, and 360 μm. The corneal thickness values were measured by anterior-segment optical coherence tomography. All lamellas had ultraviolet-A (365 nm) absorbance measured with a 96-well plate spectrophotometer using an ultraviolet transparent microplate before riboflavin instillation and preand post-crosslinking according to the Dresden protocol. Results: The ultraviolet absorbance profiles of the 180, 300, and 360 μm groups were obtained as α-coefficients of 12.85, 76.55, and 120.27, respectively. A theoretical formula was calculated though a statistical analysis that demonstrated the correlation between stromal lamellar thickness and ultraviolet absorbance. Conclusions: Corneal thickness and ultraviolet-A spectral absorbance of corneal lamellas showed linear correlation. These findings can potentially contribute to the optimization of ultraviolet-A application during crosslinking, making the treatment of corneas with thickness <400 μm safe and personalized energy delivery for each corneal thickness.

Deep anterior lamellar keratoplasty and penetrating keratoplasty in macular corneal dystrophy: comparison of visual and topographic outcomes and complications

ABSTRACT Purposes: This study aims to assess and compare the postoperative visual and topographic outcomes, complications, and graft survival rates following deep anterior lamellar keratoplasty and penetrating keratoplasty in patients with macular corneal dystrophy. Methods: In this study we enrolled 59 patients (23 male; and 36 female) with macular corneal dystrophy comprising 81 eyes. Out of these, 64 eyes underwent penetrating keratoplasty, while 17 eyes underwent deep anterior lamellar keratoplasty. The two groups were analyzed and compared based on best-corrected visual acuity, corneal tomography parameters, pachymetry, complication rates, and graft survival rates. Results: After 12 months, 70.6% of the patients who underwent deep anterior lamellar keratoplasty (DALK) and 75% of those who had penetrating keratoplasty (PK) achieved a best-corrected visual acuity of 20/40 or better (p=0.712). Following surgery, DALK group showed lower front Kmean (p=0.037), and Q values (p<0.01) compared to the PK group. Postoperative interface opacity was observed in seven eyes (41.2%) in the DALK group. Other topography values and other complications (graft rejection, graft failure, cataract, glaucoma, microbial keratitis, optic atrophy) did not show significant differences between the two groups. The need for regrafting was 9.4% and 11.8% in the PK and DALK groups, respectively (p=0.769). Graft survival rates were 87.5% and 88.2% for PK and DALK; respectively (p=0.88 by Log-rank test). Conclusion: Both PK and DALK are equally effective in treating macular corneal dystrophy, showing similar visual, topographic, and survival outcomes. Although interface opacity occurs more frequently after DALK the visual results were comparable in both groups. Therefore, DALK emerges as a viable surgical choice for patients with macular corneal dystrophy without Descemet membrane involvement is absent.

Amniotic membrane transplantation for neurotrophic corneal ulcers

ABSTRACT Purpose: To evaluate the clinical results of cryopreserved amniotic membrane transplantation as a treatment option for refractory neurotrophic corneal ulcers. Methods: This prospective study included 11 eyes of 11 patients who underwent amniotic membrane transplantation for the treatment of refractory neurotrophic corneal ulcers at Hospital de Clínicas da Universidade Federal do Paraná, in the city of Curitiba, from May 2015 to July 2021. Patients underwent different surgical techniques in which the amniotic membrane was applied with the epithelium facing upward to promote corneal re-epithelialization. Results: The median age of the patients was 60 years (range, 34-82 years), and 64% were men. The predominant etiology of corneal ulcers was herpes zoster (45% of cases). Approximately one-third of the patients (27%) were chronically using hypotensive eye drops, and more than half (54%) had previously undergone penetrating corneal transplantation. At the time of amniotic membrane transplantation, 18% of the eyes had corneal melting, 9% had corneal perforation, and the others had corneal ulceration without other associated complications (73%). The time between clinical diagnosis and surgical treatment ranged from 9 days to 2 years. The corrected visual acuity was worse than 20/400 in 90% of the patients preoperatively, with improvement in 36% after 3 months of the procedure, worsening in 18% and remaining stable in 36%. Of the patients, 81% complained of preoperative pain, and 66% of them reported total symptom relief after the surgical procedure. In one month, 54.6% of the patients presented a closure of epithelial defect, and half of the total group evolved with corneal thinning. The failure rate was 45.5% of the cases. Conclusion: Cryopreserved amniotic membrane transplantation can be considered a good alternative for treating refractory neurotrophic corneal ulcers, as it resulted in significant improvement in pain (66%) and complete epithelial closure (60%) in many patients at 1 month postoperatively. Notably, the high failure rate highlights the need for further studies to identify patientand ulcer-related factors that may influence the outcomes of this procedure.

The association of pre-photorefractive keratectomy Schirmer-1 test value with postoperative corneal epithelial thickness, ocular surface discomfort, and visual acuity

ABSTRACT Purpose: To investigate the association of pre--photorefractive keratectomy Schirmer-1 test value with post--photorefractive keratectomy central corneal epithelial thickness, ocular surface disease index score, and uncorrected distance visual acuity. Methods: Patients were categorized according to preoperative Schirmer-1 value: the normal Schirmer Group (n=54; Schirmer-1 test value, >10 mm) and the low Schirmer Group (n=52; Schirmer-1 test value, between 6 and 10 mm). We analyzed ablation depth, visual acuity, result of Schirmer-1 test (with anesthesia), tear film break-up time, ocular surface disease index score, central corneal epithelial thickness, and spherical equivalent refraction. Results: We found significant differences between the groups in Schirmer-1 test value, tear film break-up time, and ocular surface disease index score, both preoperatively and postoperatively (p<0.001). The preoperative central corneal epithelial thicknesses of the two groups were similar (p>0.05). After photorefractive keratectomy, the Schirmer-1 test value and spherical equivalent refraction decreased in both groups (p<0.05), and ocular surface disease index scores and central corneal epithelial thickness values increased in the low Schirmer Group (p<0.001) but not in the normal Schirmer Group (p>0.05). The postoperative central corneal epithelial thicknesses of the low Schirmer Group were significantly higher than those of the normal Schirmer Group (p<0.001). Postoperative uncorrected distance visual acuity did not differ significantly between the two groups (p>0.05). Conclusions: In patients with low Schirmer-1 test values before photorefractive keratectomy, the corneal epithelium thickened and ocular surface complaints increased during the postoperative period. However, changes in the corneal epithelium did not affect the postoperative uncorrected distance visual acuity. To reduce postoperative problems on the ocular surface in these patients, we recommend that dry eye be treated before photorefractive keratectomy.