Corneal injury and its protection using hydro-gel patch during general anesthesia

AIM: To evaluate corneal injury during general anesthesia and analyze the protective effect of medical hydro-gel eye patch in clinics.METHODS:Seventy-sixpatientswith152 eyesundergoing general anesthesia were included. None had positive corneal fluorescein staining before surgery. Both eyes of each patient were analyzed, with one randomly allocated to receive medical hydro-gel eye patch, and the other to receive common adhesive tape as a control. Corneal injuries were evaluated by scoring fluorescein staining under a hand-held slit lamp immediately after surgery in postanesthesia care unit and 24 h thereafter. Patients’ discomforts were also evaluated.RESULTS: Twelve eyes(15.8%) in the hydro-gel patch group and 30 eyes(39.5%) in the adhesive tape group showed corneal injury immediately after surgery. The eyes protected with hydro-gel patch showed statistically less corneal fluorescein staining than the control group.Four eyes in hydro-gel patch group and 6 eyes in adhesive tape group suffered discomfort immediately after surgery without intergroup difference and all discomforts disappeared after 24h(P =0.257). No side effect was observed in hydro-gel patch group, while 5eyes had brow avulsion and 2 got skin itching in adhesive tape group.CONCLUSION: Corneal injury complication was morefrequent than we thought following general anesthesia.The medical hydro-gel eye patch can protect the occurrence of corneal injury following general anesthesia.

Research progress on animal models of corneal epithelial-stromal injury

A corneal epithelial-stromal defect is recognized as a major contributor to corneal scarring.Given the rising prevalence of blindness caused by corneal scarring,increasing attention has been focused on corneal epithelialstromal defects.Currently,the etiology and pathogenesis of these defects remain inadequately understood,necessitating further investigation through experimental research.Various modeling methods exist both domestically and internationally,each with distinct adaptive conditions,advantages,and disadvantages.This review primarily aims to summarize the techniques used to establish optimal animal models of corneal epithelial-stromal injury,including mechanical modeling,chemical alkali burns,post-refractive surgery infections,and genetic engineering.The intention is to provide valuable insights for studying the mechanisms underlying corneal epithelial-stromal injury and the development of corresponding therapeutic interventions.

Anti-inflammatory effects of a synthetic peptide derived from pigment epithelium-derived factor on H2O2-induced corneal injury in vitro

Background The common pathological characteristics of corneal injury include inflammatory factors activation, vascular endothelial cells or inflammatory cells infiltration into lesions, corneal edema, corneal neovascularization （CNV）, and scar formation. PEDF-34 is the functional fragment of pigment epithelium-derived factor （PEDF） that has anti-angiogenic and anti-inflammatory properties and contains an N-terminal 34-amino acid peptide. This study was to investigate the anti- inflammatory effects of PEDF-34 on H202-induced corneal injury in vitro. Methods After cultured in H202 （0.1 mmol/L） for 2 hours, human corneal fibroblasts （HCFs） and human umbilical vein endothelial cells （HUVECs） were treated with PEDF-34-nanoparticles （NPs） at different concentrations （0.1, 0.5, 1.0, 2.0 μg/ml） or 2.0 μg/ml controI-NPs for 24 hours. The viable cells were quantified using the MTT assay. Western blotting or ELISA analysis was performed for measuring the human vascular endothelial growth factor （VEGF） and intercellular adhesion molecule-1 （ICAM-1） expression of both HCFs and HUVECs. VEGF and nuclear factor KB （NF-KB） mRNA levels of HCFs were semi-quantified by RT-PCR. Results The survival rates of HCFs or HUVECs stimulated by H202 did not decrease significantly （P 〉0.05） compared to those in the normal conditions. As compared to controI-NP group, PEDF-34-NPs had dose-dependent inhibitive effect on HUVECs with the MTT assay, but not HCFs. Western blotting analysis showed that the VEGF and ICAM-1 levels in the HCFs and HUVECs stimulated by H202 were significantly higher than those in the normal conditions, which were decreased dramatically in those treated with PEDF-34-NPs. RT-PCR analysis revealed that the VEGF mRNA and NF-KB mRNA levels increased in H202-stimulated HCFs, while both of them decreased in PEDF-34-NP groups dose dependently. Conclusions PEDF-34-NPs may play an important role in regulating the NF-kB pathway, inhibiting inflammatory activity. PEDF-34-NPs may be a potential new drug for treating corneal injury in the future.

Liquefaction for cataract extraction

A systematic review of the recent literature regarding the implementation of the liquefaction in cataract surgery and its short-term and long-term outcomes in various parameters that affect the quality of patients＂ life, including visual rehabilitation and possible complications was performed based on the PubMed, Medline, Nature and the American Academy of Ophthalmology databases in November 2013 and data from 14 comparative studies were included in this narrative review. Liquefaction is an innovative technology for cataract extraction that uses micropulses of balanced salt solution to liquefy the lens nucleus. Most studies reported that liquefaction is a reliable technology for mild to moderate cataracts, while fragmentation difficulties may be encountered with harder nuclei.

Effects of Recombinant Human Growth Hormone on Corneal Healing, Epithelial Nerve Regeneration and Tear Inflammatory Factors in Rabbits

Objective:The goal of this study is to investigate the effects of recombinant human growth hormone(rh GH)on corneal healing,epithelial nerve regeneration and tear inflammatory factor levels in rabbits.Methods:After corneal epithelial injury models were established,fifty adult clean New Zealand white rabbits were randomly divided into two groups,normal saline was administered to the control group,while recombinant human growth hormone was administered to the observation group.The healing rate of corneal epithelial injury,the regeneration ability of corneal epithelial nerve and the level of inflammatory factors in tears were observed and compared between the two groups of rabbits before and 24,48,72 and 96 h after modeling.Results:There were significant differences in corneal epithelial healing rate,time and interaction between the two groups(P<0.05).The experimental group exhibited a superior healing rate of corneal epithelium at 24,48,72,and 96 h compared to the control group(P<0.05).There were significant differences in central cornea sensitivity between the two groups,along with variations in time and interaction(P<0.05).There was no significant difference in the central corneal sensitivity between the two groups before modeling and at 24,72 and 96 h after modeling(P>0.05),whereas the experimental group exhibited a higher central corneal sensitivity compared to the control group at 48 h after modeling(P<0.05).There were significant differences in IL-1α,TNF-α,IL-17a and IL-21 between the two groups(P<0.05).There were significant differences in IL-17a and IL-21 between the two groups(P<0.05).The experimental group exhibited a significant decrease in IL-1αlevels compared to the control group between 24 and 72 h after modeling(P<0.05),the experimental group exhibited a substantial increase in IL-17a levels compared to the control group at 72 h after modeling(P<0.05),and the level of TNF-αin the experimental group was significantly lower than that of the control group between 24 and 96 h after modeling.Conclusion:Recombinant human growth hormone aids in expediting the healing process of the healing of rabbit corneal epithelial injury,facilitating the restoration of epithelial nerve,and mitigating the inflammatory response.