Research progress of pigment epithelial-derived factor in ocular diseases / 国际眼科杂志(Guoji Yanke Zazhi)

As a secreted glycoprotein with a molecular weight of 50kDa, pigment epithelial-derived factor(PEDF)was originally found to be secreted by pigment epithelial cells; afterwards, it was found to be widely distributed in various organs and tissues throughout the body and played multiple biological roles. In recent years, a large number of studies have confirmed that PEDF can initiate a wide range of cellular responses in eye tissues by binding with a variety of receptors, which has the functions of regulating angiogenesis, anti-inflammatory, antioxidant stress and neurotrophic. Recent studies have found that the application of exogenous PEDF has a preferable therapeutic effect on the repair of dry eye and corneal injury. In addition, the PEDF gene encoding therapy has shown promising in the treatment of age-related macular degeneration and diabetic retinopathy. This review mainly summarizes the potential therapeutic effects and limitations of pigment epithelium-derived factors in dry eye, corneal injury, age-related macular degeneration, diabetic retinopathy and other diseases in recent years, which provides help for further research on the diagnosis and treatment of ocular diseases with PEDF.

Acute hydrops followed by corneal perforation five years after corneal cross-linking for keratoconus / Hidropisia aguda seguida de perfuração da córnea cinco anos após reticulação corneana para ceratocone

ABSTRACT We report a case of acute corneal hydrops followed by corneal perforation five years after corneal cross-linking for keratoconus. A healthy 24-year-old female patient underwent Dresden protocol cross-linking in her left eye due to advanced keratoconus. After five years of a stable cornea, she returned with epiphora, blurred vision, and a soft left eye. Acute hydrops and corneal perforation were diagnosed. There was no history of pregnancy, atopy, eye rubbing, trauma, or contact lens use. Local antibiotic and eye patching were applied. Three months after the resolution of the acute episode, she retained useful visual acuity with no need for further surgery. Although cross-linking efficiently halts keratoconus, progression can occur, leading to corneal hydrops and perforation, even in the absence of any risk factors.

RESUMO Este é o relato de um caso de hidropisia aguda seguida de perfuração corneana cinco anos após reticulação corneana para ceratocone. Uma paciente saudável de 24 anos foi submetida a reticulação corneana no olho esquerdo pelo protocolo de Dresden, devido a um ceratocone avançado. Após cinco anos com a córnea estável, a paciente retornou com epífora, visão turva e amolecimento do olho esquerdo. Foram diagnosticadas hidropisia aguda e perfuração corneana. A paciente não tinha história de gravidez, atopia, fricção ocular, trauma ou uso de lentes de contato. Foram aplicados um antibiótico local e um tampão oftalmológico. Três meses após a resolução do episódio agudo, ela manteve uma acuidade visual útil, sem necessidade de novas cirurgias. Embora a reticulação interrompa de forma eficiente o ceratocone, pode ocorrer progressão, levando a hidropisia e perfuração da córnea, mesmo na ausência de fatores de risco.

Use of the Ishikawa diagram in a case-control analysis to assess the causes of a diffuse lamellar keratitis outbreak / Aplicando o diagrama de Ishikawa em uma análise caso-controle para identificar as causas de um surto de ceratite lamelar difusa

ABSTRACT Purpose: To identify the causes of a diffuse lamellar keratitis (DLK) outbreak using a systematic search tool in a case-control analysis. Methods: An Ishikawa diagram was used to guide physicians to determine the potential risk factors involved in this outbreak. Coherence between the occurrences and each possible cause listed in the diagram was verified, and the total number of eyes at risk was used to calculate the proportion of affected eyes. Multivariate analysis was performed using logistic regression to determine the independent effect of the risk factors, after controlling for confounders and test interactions. Results: All DLK cases were reported in 2007 between June 13 and December 21; during this period, 3,698 procedures were performed. Of the 1,682 flap-related procedures, 204 eyes of 141 individuals presented with DLK. No direct relationship was observed between the occurrence of DLK and the presence of any specific factors; however, flap-lifting enhancements, procedures performed during the morning shift, and non-use of therapeutic contact lenses after the surgery were significantly related to higher occurrence percentages of this condition. Conclusions: The Ishikawa diagram, like most quality tools, is a visualization and knowledge organization tool. This systematization allowed the investigators to thoroughly assess all the possible causes of DLK outbreak. A clear view of the entire surgical logistics permitted even more rigid management of the main factors involved in the process and, as a result, highlighted factors that deserved attention. The case-control analysis on every factor raised by the Ishikawa diagram indicated that the commonly suspected factors such as biofilm contamination of the water reservoir in autoclaves, the air-conditioning filter system, glove powder, microkeratome motor oil, and gentian violet markers were not related to the outbreak.

RESUMO Objetivos: Identificar as causas de um surto de ceratite lamelar difusa (DLK) uti­lizando uma ferramenta de busca sistemática em uma análise de caso-controle. Métodos: O diagrama de Ishikawa foi usado para orientar os médicos a identificar os potenciais fatores de risco envolvidos neste surto. Coerência entre as ocorrências e cada causa possível listada no diagrama foi verificada. O número total de olhos em risco foi usada para calcular a percentagem de olhos afetados. A análise multivariada foi realizada por meio de regressão logística para determinar o efeito independente dos fatores de risco, controle de fatores de confusão e interações de teste. Resultados: Todos os casos de ceratite lamelar difusa foram relatados em 2007 entre 13 de junho e 21 de dezembro, durante este tempo foram realizados no total 3.698 procedimentos. De um total de 1.682 procedimentos relacionados a confecção de um flap, 204 olhos de 141 indivíduos apresentaram ceratite lamelar difusa. Não foi observada relação direta entre a ocorrência de ceratite lamelar difusa e a presença de qualquer fator específico; no entanto, procedimentos que incluíam um novo levantamento do flap, procedimentos realizados no turno da manhã, e o não-uso de lentes de contato terapêuticas após a cirurgia foram significativamente relacionados com a ocorrência desta complicação. Conclusão: O diagrama de Ishikawa é uma ferramenta de visualização e organização do conhecimento. Essa sistematização permitiu aos investigadores pesquisar todas as possíveis causas do surto de ceratite lamelar difusa. Uma visão clara de toda a logística cirúrgica permitiu a gestão mais rígida dos principais fatores envolvidos no processo. A análise de caso-controle em relação a cada fatores levantados pelo diagrama indicou que fatores sempre suspeitos, tais como: contaminação do biofilme da água do reservatório das autoclaves, sistema de filtro de ar-condicionado, pó de luva, óleo de motor do microcerátomo e marcador violeta de genciana, não foram relacionados com o surto.

Application and research progress of bone marrow mesenchymal stem cells in corneal injury repair / 国际眼科杂志(Guoji Yanke Zazhi)

Bone marrow mesenchymal stem cells (BMSCs) are a class of cells that can differentiate into different kind of corneal cells both in vitro and in vivo,which include corneal epithelial cells,limbal epithelial cells and corneal stromal cells.BMSCs could differentiate into corneal epithelial cells after transplantation,which can not only repair the damaged corneal,but also relieve inflammatory injury caused by the inflammatory cell infiltration.The other function of BMSC transplantation is to reduce the rejection after corneal transplantation by inhibiting cell damage and apoptosis.BMSC can also express a variety of factors on the carrier,these factors paly the important role in promoting the proliferation of limbal stem cells.These findings above provide a new direction for the fundamental study of ophthalmology,and put forward new clinical treatment ideas for corneal disease,both of them have broad protect for development,in this paper,the research status and progress of BMSC in the repair of corneal injury are reviewed.

Ultrastructure and histopathology of cornea after femtosecond laser-assisted deep lamellar keratoplasty for acute corneal alkali burn / 中华实验眼科杂志

Background To maintain corneal transparency is important for good visual function.A new treatment concept and the selection of surgical techniques and timing of surgery are critical for stopping the infringement of cornea tissue after alkali burning and other chemical warfare agents.Objective This study was to investigative the ultrastructure and histopathological status following the femtosecond laser-assisted deep lamellar keratoplasty (DLK) for acute alkali burn of cornea.Methods Acute corneal alkali burn models were established in 12 New Zealand rabbits by putting the 6 mm filter paper with 1 mol/L NaOH at the central cornea for 30 seconds.The rabbits were randomly allocated to femtosecond laser-assisted DLK group and model control group according to the randomized number table method.Femtosecond laser-assisted DLK was performed to transplant the corneal grafts of domestic rabbits to the model rabbits 24 hours after burning.The rabbits were sacrificed 1 week,2 weeks and 4 weeks after modeling,and the corneas were extracted for the preparation of corneal section.The cornea were performed with hematoxylin and eosin staining to assess the histopathological status under the optical microscope,and the ultrastructure of grafts and corneas was examined under the transmission electron microscope (TEM).Results Acute corneal alkali bourn models were successfully eatablished.In the fourth week after surgery,corneal graft was clear in the femtosecond laser-assisted DLK group.However,corneal swelling,conjunctival congestion and neovascularization were found in the model control group.Histopathological examination revealed the defect of corneal epithelium,edema of stroma,loose arrangement of collagen fibers,much vacuoles,few neovascularization and infiltration of a large number of inflammatory cells in the model control group,but in the femtosecond laser-assisted DLK group,the inflammatory response was slight.More desmosomes among the endothelial cells were seen,and the nuclei were intact in the grafts.In the fourth week after surgery,the transplanted corneas were transparent with the regular arrangement of collagen fibers and entire fibroblasts in the femtosecond laser-assisted DLK group under the TEM.However,flat surface corneal epithelial cells and shedding of some epithelial cells were exhibited in the modelcontrol group.Conclusions Femtosecond laser-assisted DLK can effectively alleviate the inflammatory response,promote epithelial healing and enhance intercellular tight junction in the cornea with acute alkali burn.

Analysis of the risk factors predisposing to fungal, bacterial & Acanthamoeba keratitis in south India.

Background & objectives: Infective keratitis is rare in the absence of predisposing factors. The pattern of risk factors predisposing to infective keratitis varies with geographical regions and also influences the type of infection that occurs. The present study was aimed to identify the specific risk factors that predispose the infective keratitis (non viral) and to determine the association between the risk factors identified and the microbial aetiology of infective keratitis in a geographic region (south India). Methods: A retrospective analysis of all patients clinically diagnosed infective keratitis (non viral) presenting between September 1999 and September 2002 was performed to identify risk factors. After diagnosing infective keratitis clinically, corneal scrapes were performed and subjected to microscopy and culture. Results: A total of 3295 patients with infective keratitis were evaluated, of whom, 1138 (34.5%) patients had fungal growth alone, 1066 (32.4%) had bacterial growth alone, 33 (1%) had Acanthamoeba growth alone, 83 (2.5%) had mixed microbial growth and the remaining 975 (29.6%) had no growth. Corneal injury was identified in 2356 (71.5%) patients and it accounted for 91.9 per cent in fungal keratitis (P<0.0001) (OR: 73.5; 95%CI: 61.3-98.5), 28.1 per cent in bacterial keratitis and 100 per cent in Acanthamoeba keratitis (P<0.0001). Injuries due to vegetative matter (61.2%) was identified as significant risk for fungal keratitis (P<0.0001) (OR: 15.73; 95%CI: 12.7-19.49) and mud (84.85%) for Acanthamoeba keratitis (P<0.0001) (OR: 16.52; 95%CI: 6.35-42.99). Co-existing ocular diseases predisposing to bacterial keratitis accounted for 724 (69%) patients (P<0.0001) (OR: 33.31; 95%CI: 26.98-41.12). Bacterial pathogens alone were recovered from all 35 patients with contact lens associated keratitis (100%). Co-existing ocular diseases (78.3%) were frequently documented among patients older than 50 yr (P<0.0001) (OR: 27.0; 95%CI: 25.0-28.0) and corneal injury (89.7%) was frequently recorded among patients younger than 51 yr (P<0.0001) (OR: 72.0; 95%CI: 70.0-73.0). Interpretation & conclusions: Corneal injury was found to be the principal risk factor for fungal and Acanthamoeba keratitis, while co-existing ocular diseases for bacterial keratitis. Corneal injury with vegetative matter was more often associated with fungal keratitis and injury with mud with Acanthamoeba keratitis.

Clinical Feature of Chemical Corneal Injuries

PURPOSE: To establish a treatment regimen and preventive measures through clinical study and demographic profile of chemical corneal injury cases. METHODS: The records of all patients presenting with chemical corneal injuries from January 1 1997 to December 31 2003 were evaluated. One hundred forty-three chemical corneal injuries in seventy-eight patients presenting to the Dongguk University Hospital were analyzed. Patients was divide into three groups in accordance to occupation (Group I, farmer, Group II, directly chemical-agents exposure occupation, Group III, others). The records were examined to extract information about age, sex, extent of injury, chemical substances involved, place of injury, delay time of arrival at hospital and visual acuity. Classification of corneal burns was scored according to Roper-Hall. RESULTS: The patient consisted of 63 males (80.8%) and 15 females (19.2%), with a mean age of 39.21+/-13.27 years. The most common agent causing corneal injuries was pesticide, followed NaOH. Ninety-eight (68.5%) eyes showed Grade 1 burns, 27 (18.9%) eyes showed Grade 2, 15 (9.1%) eyes Grade 3 and 5 (3.5%) Grade 4. The severity of chemical corneal burn and deterioration of the visual acuity was more severe in group II than in the other groups. CONCLUSIONS: Chemical ocular injuries may lead to serous visual impairment. Therefore, proper education for appropriate handling of chemicals to prevent the accidents is important.

A Clinical Study of Ocular Injury Cases

The authors clinically analysed 2,856 ocular injury patients among 36,922 patients who visited department of ophthalmology of Chonnam National University Hospital during the 9 years form January 1, 1981 to August 31, 1989. The results were as follows: 1. The incidence of ocular injury was 15.6% of all outpatient in first group(1981-83) and 29.7% in third group(1987-89.8). There was tendency to increase group by group and the average incidence was 7.7% of all patient. Among them, 2180 cases(76.3%) were male and 676 cases(23.7%) female. Males were nearly three times as many as females. 2. In comparison with age groups, the largest group in eye injury cases was in the age group of 20-29 years(27.2%). And the incidence was more common in the age of 3rd to 4th decades(47.2%), consisting about 1/2 of the total patient. 3. According to affected side, there was no significant difference between the right eye(43.2%) and the left eye(45.6%). Both eye involvement was 320cases(11.2%) and ones ide involvement was 1301 cases(45.6%). 4. According to seasonal distribution, visits were more common in spring(27.5%) and least in autumn(22.4%). 5. In regard to days, the most patients visited on sunday(20.0%), while the least patients on monday(10.4%). 6. The most common cause of ocular injuries was violence(26.4%), followed by injuries from traffic accident(19.1%), metal particles(11.3%) and explosive material(9.6%). In the cases of ocular perforation, metal particles(26.5%) is most common cause, followed by traffic accident(24.0%), flying particle(11.3%). 7. The most common ocular injury was corneal injury(37.8%), followed by eye lid injury(20.0%), traumatic hyphema(13.5%) and conjunctival injury(12.9%). 8. The incidence of IOF for ocular perforation patients was 43 cases(7.8%), and more common in male(6.6%) than female(1.2%). 9. Before treatment, visual acuity showed 0.08 or less in 627 cases(72.6 %) and 0.6 or more in 95 cases(11.0%), however after treatment, the number of the patients with visual acuity under 0.08 decreased to 325 cases(37.6%) and over 0.6 increased to 288 cases(33.3%).