Abstract:AIM: To explore the pathogenesis and surgical outcomes of different types of myopic traction maculopathy(MTM)using optical coherence tomography(OCT).

METHODS: A total of 193 patients(210 eyes)with MTM were retrospectively included, of which 74 eyes(35.2%)underwent vitrectomy combined with internal limiting membrane(ILM)peeling. The patients were categorized into three groups: foveal detachment(FD), foveoschisis(FS)and lamellar macular hole(LMH). Based on the central foveal thickness(CFT)at baseline(M0), eyes with FD were classified into two subgroups: extensive FD and limited FD. Outcomes included best-corrected visual acuity(BCVA), CFT, posterior staphyloma height(PSH), the presence of epiretinal membrane(ERM)and ILM detachment. Risk factors for BCVA at 6mo after vitrectomy(M6)were analyzed using linear regression.

RESULTS: At M0, ERM was highly present in eyes with LMH(r_s=0.28, P<0.001). Eyes with FD and FS were characterized by higher incidence of ILM detachment(r_s=-0.25, P<0.001). After vitrectomy, CFT and BCVA significantly improved in all eyes(P<0.001). Eyes with extensive FD were characterized by a thicker CFT(r_s=0.56, P<0.001), a lower incidence of ILM detachment(r_s=-0.25, P=0.034)and a thicker nasal PSH(r_s=0.27, P=0.024)than eyes with limited FD. Eyes with extensive FD were associated with a worse BCVA at M0(P=0.013)and M6(P=0.030)than eyes with limited FD. Extensive FD(β=-0.295, P=0.042)and BCVA at M0(β=0.669, P<0.001)were risk factors for a worse BCVA at M6.

CONCLUSION: There are several pathogenetic mechanisms in MTM. ILM detachment may exert a dominant role in the development of FD and FS, while ERM may have a role in LMH. Vitrectomy combined with ILM peeling improved functional and anatomical outcomes in MTM patients. Eyes with extensive FD may carry a poor prognosis.

Abstract:AIM: To evaluate the efficacy of transplantation of human umbilical cord mesenchymal stem cells(hUCMSCs)in the treatment of corneal alkali burn in rabbits, and study the infiltration of polymorphonuclear neutrophils(PMNs)and the changes of vascular endothelial growth factor(VEGF)expression.

METHODS: Corneal alkali burn models were established in right eyes of 75 healthy Japanese white rabbits, which were divided into three groups(group A, B and C), with 25 rabbits in each group. Group A was treated with amniotic membrane combined with hUCMSCs on the day after corneal alkali burn. Group B was treated with amniotic membrane only. Group C did not give any treatment after corneal alkali burn. At 3, 7, 14, 21 and 28d after corneal alkali burn, the corneal recovery was observed by slit lamp and photographed, the growth of corneal neovascularization(CNV)was scored, and corneal tissue was separated to make pathological sections. PMNs infiltration was observed by hematoxylin-eosin(HE)staining, and the expression of VEGF was determined by immunohistochemical staining.

RESULTS: The growth of CNV in group A was much slower than that in group B at 14d after alkali burn. The CNV growth score around lesions of group A was significantly lower than that of group B(P<0.05). The quantity of PMNs increased on the 3d with the stromal layer of cornea infiltrated, relatively decreased on the 7d, shown a peak on the 14d, and then decreased gradually. Early infiltration after alkali burn was in the corneal stroma of the lesion area, and the extent of infiltration was equal to the ulcer area at later stage. The cell densities of corneal PMNs in group A and group B were significantly lower than those in group C at all time points after alkali burns(P<0.05), and those in group A were significantly lower than group B at 14 and 21d(P<0.05). The expression levels of corneal VEGF in all groups after alkali burn reached peak at 7～14d and decreased significantly at 28d, and the expression levels of VEGF in group A and group B at all time points after alkali burn were significantly lower than those in group C(P<0.05), and group A was significantly lower than that in group B at 7, 14 and 21d(P<0.05).

CONCLUSION: The transplantation of hUCMSCs after alkali burn cornea can reduce the formation of CNV and inhibit corneal revascularization after alkali burn. The corneal pathological lesions and vascularization are closely related to PMNs and VEGF.

Abstract:AIM: To investigate the role and mechanism of methyltransferase-like 3(METTL3)-mediated N6-methyladenosine(m⁶A)methylation modification in regulating biological activity of vascular endothelial cells in the pathogenesis of choroidal neovascularization.

METHODS: Human umbilical vein endothelial cells(HUVEC)cultured in vitro were divided into the following groups: control group(normal culture), low density lipoprotein(LDL)group, fluorescence-labelled LDL(Dil-LDL)group, 12.5μg/mL and 25μg/mL oxidized LDL(ox-LDL)groups, 12.5μg/mL and 25μg/mL fluorescence-labelled ox-LDL(Dil-ox-LDL)groups, DMSO group, STM2457(METTL3 inhibitor)group, DAPT group; and monkey retina-choroidal endothelial cells(RF/6A)cultured in vitro were divided into control group, DMSO group, 12.5 μg/mL ox-LDL group, and DAPT group. Endocytosed lipoprotein level was examined through fluorescence microscopy. RNA m⁶A methylation level was detected through a dot blot assay. Protein and RNA levels of METTL3 or angiogenesis-related markers were measured through Western blot assays and real-time quantitative polymerase chain reaction(RT-qPCR), respectively. METTL3 expression and localization were investigated through immunofluorescence. Cell migratory and tube formation capacities were assessed through transwell migration and tube formation assays, respectively.

RESULTS: Endocytosed lipoprotein levels in HUVECs exposed to Dil-LDL, 12.5μg/mL and 25μg/mL Dil-ox-LDL groups were significantly higher than those in the control group. 12.5μg/mL and 25μg/mL ox-LDL groups significantly increased m⁶A methylation(all P<0.05), METTL3 protein expression(all P<0.01), and cell migration and angiogenesis capacities(all P<0.01). METTL3 mRNA level was significantly unregulated in the 12.5μg/mL ox-LDL group(P<0.05). In comparison to the DMSO group, the addition of STM2457 caused significant decrease in m⁶A methylation level(P<0.05), expression of VEGF and other angiogenesis-related markers(all P<0.05), cell migration and angiogenesis capacities(all P<0.01)and the expression of NICD(P<0.05). However, there were no significant differences in METTL3 protein and mRNA levels(all P>0.05). The expression of VEGF and NICD(all P<0.05), as well as the ability of cell migration and angiogenesis of RF/6A, was all significantly decreased in the DAPT group compared to the DMSO group(all P<0.01).

CONCLUSION: METTL3-mediated m⁶A methylation modification promotes angiogenesis in vascular endothelial cells via the Notch signaling pathway in the pathogenesis of choroidal neovascularization.

Abstract:AIM: To investigate the effects of curcumin on the proliferation and apoptosis and migration of human pterygium fibroblasts(HPF)in vitro.

METHODS: A total of 7 cases of pterygium tissue removed at our hospital from November 24, 2021 to December 16, 2021 were collected. Then, primary fibroblasts were cultured in vitro and identified by immunofluorescence staining. HPF were treated with 0, 10, 20, 40, 80 and 160μmol/L curcumin containing equal amount of dimethyl sulfoxide for 24h, then the cell proliferation was detected by CCK8 assay. According to the results of CCK8, the cells were divided into control group, 20μmol/L curcumin group and 40μmol/L curcumin group, and the cells were treated with corresponding concentration of curcumin for 24h in each group. Flow cytometry was used to detect apoptosis, Transwell migration assay was used to detect cell migration, and real-time fluorescence quantitative polymerase chain reaction and Western blot were used to detect the expression of mRNA and protein of B-cell lymphoma-2 associated X protein(Bax), B-cell lymphoma-2(Bcl-2), Cyclin D1 and matrix metalloproteinase 2(MMP2).

RESULTS: Compared with the control group, both 20μmol/L curcumin group and 40μmol/L curcumin group can inhibit the proliferation and migration of HPF and induce its apoptosis(all P<0.05). Compared with the control group, 20μmol/L curcumin group can down-regulate the mRNA expression of Cyclin D1 and MMP2, up-regulate the mRNA expression of Bax, and down-regulate the protein expression of Bcl-2(all P<0.05). Compared with the control group, 40μmol/L curcumin group can down-regulate the expression of mRNA and protein of Bcl-2, Cyclin D1 and MMP2, and up-regulate the expression of mRNA and protein of Bax(all P<0.05). Compared with 20 μmol/L curcumin group, the 40 μmol/L curcumin group can down-regulate the mRNA expression of MMP2, down-regulate the protein expression of Bcl-2, and up-regulate the mRNA and protein expression of Bax(all P<0.05).

CONCLUSION: Curcumin can inhibit the proliferation of HPF by inhibiting the expression of Cyclin D1, induce the apoptosis of HPF by down-regulating Bcl-2 and up-regulating the expression of Bax, and inhibit the migration of HPF by down-regulating the expression of MMP2.

Abstract:AIM: To explore the mechanism of fructus lycii in treating dry eye based on network pharmacology and experimental verification.

METHODS: Taking “fructus lycii” as key words, the active ingredients and target of fructus lycii were searched by using Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform(TCMSP). Gene targets related to dry eye(DE)were searched by GeneCards and OMIM databases. The target genes of fructus lycii and DE were imported into Venn software to obtain the intersection target map of them. After that, the data were imported into the String database to obtain the PPI protein-protein interaction network diagram. Using Cytoscape3.7.2 software, the PPI protein-protein interaction network diagram was constructed for active ingredients, target sites and related diseases of fructus lycii. The Bioconductor platform and R language were used for gene ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)enrichment analysis. And the key targets in the pathogenesis of DE were verified by experiments.

RESULTS: Through TCMSP, 45 types of effective chemical components of fructus lycii, 174 target genes corresponding to active components and 131 common target genes with DE were screenedout. In accordance with the network topology of “drug-composition-disease-target”, 27 main effective components of fructus lycii were found in the treatment of DE. The PPI network was analyzed according to the high degree value, which is the key targets of fructus lycii for DE treatment, mainly including AKT1, VEGFA, CASP3, IL1B, JUN, PTGS2, CXCL8, etc. According to GO enrichment analysis, 166 biological functions and processes of fructus lycii for DE treatment were obtained. KEGG enrichment analysis showed that 31 signaling pathways were involved. Additionally, experimental verification displayed that the protein expressions of AKT1, interleukin-6(IL-6), tumor necrosis factor(TNF-α)and IL-17 in conjunctiva tissue of the DE model group were significantly increased.

CONCLUSIONS: Through network pharmacology, this study confirmed that the treatment of DE by fructus lycii is a complex process involving multi-components, multi-targets and multi-pathways, and that the treatment of DE by fructus lycii is mainly regulated by anti-inflammatory and apoptosis-related molecules.

Abstract:AIM: To investigate the changes in retinal and choroidal blood flow after pars plana vitrectomy(PPV)for proliferative diabetic retinopathy(PDR).

METHODS: A cross-sectional study was conducted on 35 patients(35 eyes)who were diagnosed as monocular PDR and received 23GPPV in ophthalmology department of the Second People's Hospital of Hefei between September 2020 and July 2022. All eyes underwent swept-source optical coherence tomography angiography(SS-OCTA)examination. Retinal and choroidal vascular parameters within 3mm×3mm of macular zone were measured by built-in analyzer, and its correlation with postoperative best corrected visual acuity(BCVA)was analyzed.

RESULTS: The follow-up was 1～22(average 9.72±6.67)mo. At the last follow-up, flow area(FA)of intermediate capillary plexus(ICP)layer in paranasal foveal region was significantly reduced in PPV eyes(0.31±0.06mm²)compared with contralateral eyes(0.38±0.05mm²), and FA of deep capillary plexus(DCP)in temporal foveal region was significantly lower in PPV eyes(0.19±0.08mm²)than contralateral eyes(0.27±0.07mm²; all P<0.05). Choroidal vascularity index(CVI)were lower in PPV eyes than contralateral eyes in parafoveal subregions except temporal region(P<0.05). After PPV, BCVA had a certain correlation with the density and FA of middle and deep retinal vessels.

CONCLUSIONS: Eyes with severe PDR may be prone to having a decrease in the DCP and parafoveal choroidal perfusion in the parafoveal regions after PPV than contralateral eyes.

Abstract:AIM: To investigate the role of visual perception training on the recovery of visual function at all levels and the improvement of perceptual eye position in children with intermittent exotropia(IXT).

METHODS: Prospective clinical study. A total of 74 patients with IXT who received corrective surgery for strabismus in the Ophthalmology Department of the First People's Hospital of Lanzhou City from January to June 2022 were collected and followed up for 3mo. The patients were randomly divided into 2 groups at 1d after surgery: 35 patients in the training group received binocular visual perception training, and 39 patients in the control group did not receive visual training. The changes of visual function and perceived eye position at all levels were observed at 1d and 3mo after operation.

RESULTS: There were 24 patients(69%)with simultaneous perception in the training group at 1d after surgery and 34 patients(97%)with recovered visual function at 3mo after surgery, which was significantly higher than 1d after surgery(P=0.002). Furthermore, there were 22 cases(56%)of fusion function in the control group at 3mo after surgery, 13 cases(33%)of far stereopsis, 20 cases(51%)of dynamic stereopsis and 17 cases(44%)of static fine stereopsis. In the training group, there were 31 cases(89%)of fusion function, 25 cases(71%)of far stereopsis, 30 cases(86%)of dynamic stereopsis and 27 cases(77%)of static fine stereopsis, which were significantly higher than those in the control group(all P<0.05). The degree of perceived eye displacement in the training group decreased more significantly than that in the control group(all P<0.05).

CONCLUSION: Postoperative visual perceptual training in children with IXT can promote recovery of visual function at all levels, improve perceptual eye position and enhance the control of eye position at the perceptual level of the brain.

Abstract:Diabetic retinopathy(DR)is the main cause of visual impairment and blindness in working-age people, which is the most common microvascular disease among diabetes complications.Hyperglycemia state can result in the aggravation of oxidative stress, release a large number of reactive oxygen species(ROS), and cause damage to protein, DNA or RNA in tissues and cells, thus causing cell death. Oxidative stress is considered as one of the important factors for the occurrence and development of DR. Antioxidant defense system is the key component of maintaining redox homeostasis. Superoxide dismutase(SOD)is a major antioxidant enzyme, which maintains the first line of defense in the antioxidant enzyme library. There are three kinds of SOD isozymes in mammals, which mainly protect cells from superoxide damage by accelerating the mutation reaction of SOD. It may delay the occurrence and development of DR by regulating the level of antioxidant enzyme SOD. Currently, the pathogenesis of DR remains unclear. In this paper, the protective effect of antioxidant enzyme SOD on pericytes and ganglion cells in DR was reviewed.

Abstract: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.

Abstract:Age-related eye diseases are a series of ophthalmic diseases caused by degenerative disease of ocular tissues, and age-related macular degeneration(ARMD), age-related cataract(ARC), diabetic retinopathy(DR)and glaucoma are the four most common age-related eye diseases. With the increasing aging of the global social population, the incidence of these eye diseases is also increasing year by year. Metformin is currently one of the most commonly used hypoglycemic agents in clinical practice. It has become the drug of choice for treating type 2 diabetes after more than 60 years of clinical practice. In recent years, metformin has shown great potential in the prevention and treatment of tumors, systemic diseases and age-related diseases, and the mechanisms of action involved in anti-oxidative stress, anti-inflammation, and induction of autophagy are also closely related to the pathological changes of age-related eye diseases. The paper aims to review the current research status and potential application value of metformin in age-related eye diseases.

Abstract:Interleukin-6(IL-6)is a pleiotropic cytokine produced by monocytes, macrophages, T lymphocytes and other cell types. It is significantly up-regulated in the process of infection and inflammation, and is the core cytokine of the host's defense against environmental stresses(such as injury and infection). Abnormal and persistent IL-6 production is closely associated with the development of various autoimmune and inflammatory diseases. A growing number of studies have shown that IL-6 plays a critical role in ocular inflammation and angiogenesis in the conjunctiva, cornea, uvea and retina. Blockade of IL-6 ameliorates chronic and refractory intraocular inflammation. This article aims to review the role as well as the mechanism of IL-6 in ocular inflammatory diseases, attempting to have a deep and systematic understanding of the role of IL-6 in ocular inflammatory diseases.

Abstract:The human eye has various axes and angles, of which the angle Kappa is an important indicator of the centrality of the human eye and is widely used in ophthalmic surgery. Proper preoperative evaluation and application of the angle Kappa facilitated the achievement of optimal postoperative visual quality. Chord mu is a new term that has emerged recently to better express the angle Kappa. The two concepts are not well understood clinically, limiting their usefulness. Therefore, to better understand the angle Kappa and chord mu, the definitions and connections between them are presented separately in this paper. Meanwhile, the application of angle Kappa in strabismus surgery was summarized, the method for compensating large angle Kappa in corneal refractive surgery and the clinical significance of angle Kappa in predicting postoperative centrality of multifocal intraocular lens(MIOL)in phacoemulsification combined with MIOL implantation were discussed, with a view to providing references for clinical work.

Abstract:Retinopathy of prematurity(ROP)is the primary cause of preventable childhood blindness. It is hard to screen, diagnose and objectively evaluate. There are various modalities for ROP screening, including various contact or non-contact imaging devices, smart phone-based fundus photography, and artificial intelligence-based fundus image analysis. The diagnosis of ROP is based on visualization and recording of the entire retinal fundus of ROP, which is also the basis for subsequent screening, treatment assessment. Fundus screening is critical for early recognition and facilitates early detection and prompt referral. Potential features may be found by analyzing and summarizing the characteristics of ROP fundus images. Subsequently, timely and targeted ROP prevention and treatment could be performed. Artificial intelligence promotes automatic, quantifiable and objective diagnosis of ROP. This article reviews commonly used clinical fundus examination methods and fundus image characteristics of ROP and summarizes the latest research progress on the application of artificial intelligence in the automatic diagnosis of ROP.

Abstract:Herpes simplex keratitis(HSK), caused by the infection of herpes simplex virus type Ⅰ(HSV-1)in cornea, is a global blinding corneal disease. After the primary infection in ocular surface, HSV-1 is transported into trigeminal ganglion and establishes the life-lasting latency, and it results in recurrent keratopathy. In the process of studying the latent mechanism of HSV, it has been gradually recognized that both the virus itself and the host response regulate the latent process of HSV. In recent years, a large number of research results have been obtained on the molecular mechanisms of invasion, immunity, latency and recurrence of neurotropic viruses, which provide new ideas for the prevention and treatment of HSK. In the present review, the recent progress of HSV latency mechanism in trigeminal ganglion after the primary infection in corneal surface was introduced, and the unsolved basic and clinical problems in HSK were discussed.

Abstract:AIM: To systematically evaluate the effects of low-energy red light on choroidal thickness(ChT), spherical equivalent(SE), and axial length(AL)in myopic children.

METHODS: A total of 8 databases, including Pubmed, Embase, Cochrane Library, Web of Science, CNKI, WanFang Database, VIP Database and China Biomedical Literature Database, were electronically retrieved to collect the clinical randomized controlled trial(RCT)of low-energy red light in myopia, with red light intervention as an experimental group and glasses as a control group. The retrieval time limit is from the establishment of the database to January 2023. According to the recommendation of the Cochrane Handbook, literature quality and risk of bias were evaluated. Revman5.4 software was used for Meta-analysis.

RESULTS: Totally 8 RCT about red-light treatment with myopia were included. The sample size for ChT analysis contained 407 eyes in the red-light group and 425 eyes in the control group; SE analysis included 490 eyes in the red-light group and 518 eyes in the control group; sample size for AL analysis were 518 eyes in the red-light group and 539 eyes in the control group. The differences in ChT, SE and AL between the groups were statistically significant(ChT: WMD=37.81, 95%CI: 21.55～54.07, P<0.001; SE: WMD=0.58, 95%CI: 0.46～0.71, P<0.001; AL: WMD=-0.31, 95%CI: -0.39～-0.24, P<0.001).

CONCLUSION: Specific red light can promote the increase of ChT while inhibit SE and AL. However, its long-term efficacy and side effects remain unclear. The above conclusions need to be further clarified by more RCT with large samples.

Abstract:AIM: To compare the efficacy of and without small incision lenticule extraction(SMILE)with cyclotorsion compensation for astigmatism correction.

METHODS: PubMed, Web of Science, EMBASE, Cochrane and CNKI, VIP, CBM, and Wan Fang Data were searched for clinically controlled studies from January 2010 to August 2022, including an experimental group with cyclotorsion compensation during SMILE and a control group without cyclotorsion compensation during SMILE. After literature screening, quality evaluation, and data extraction by two researchers independently, the Meta-analysis of uncorrected distance visual acuity(UDVA), residual astigmatism, vector analysis indicators for measuring the astigmatism correction including absolute value of angle of error(|AE|)and magnitude error(ME), and post-operative total higher order aberrations, spherical aberration and coma was carried out with Stata 16.0 software.

RESULTS: Seven studies with a total of 846 eyes(442 in the experimental group, 404 in the control group)were finally included. The Meta-analysis showed that there were significant differences in the percentage of eyes with residual astigmatism ≥1.00D(OR=0.17, 95%CI: 0.06～0.49, P<0.01), |AE|(WMD=-1.56, 95%CI: -2.68～-0.45, P<0.01), the coma(WMD=0.06, 95%CI: -0.08～-0.04, P<0.01), and the total higher order aberrations(WMD=-0.04, 95%CI: -0.06～-0.02, P<0.01). However, there were no differences in the postoperative UDVA(WMD=0.00, 95%CI: -0.02～0.01, P=0.54), residual astigmatism(WMD=0.08, 95%CI: -0.02～0.18, P=0.10), ME(WMD=-0.01, 95%CI: -0.14～0.12, P=0.85), and the spherical aberration(WMD=0.03, 95%CI: -0.07～0.13, P=0.52).

CONCLUSION: Cyclotorsion compensation in SMILE can reduce the angular error caused by eye rotation during astigmatism correction. It also decreases postoperative residual astigmatism. Overall, the SMILE with cyclotorsion compensation is superior in clinical efficacy of the precise correction of astigmatism.

Abstract:AIM: To investigate the clinical efficacy of suture-guided gonioscopy-assisted transluminal trabeculotomy(GATT)combined with phacoemulsification in the treatment of primary open angle glaucoma(POAG).

METHODS: A total of 84 patients(84 eyes)with POAG and cataract who underwent surgery in our hospital from January 2021 to July 2022 were selected and randomly divided into two groups. There were 43 cases(43 eyes)in the combined group who underwent suture-guided GATT combined with phacoemulsification, and 41 cases(41 eyes)in the simple group who underwent suture-guided GATT. The two groups were followed up for 3mo to compare the surgical success rate, intraocular pressure, topical intraocular pressure-lowering drugs, visual acuity and postoperative complications.

RESULTS: There was no significant difference in overall success rate between the combination and simple groups at 3 mo after surgery(88% vs. 85%, P>0.05). The intraocular pressure levels and topical intraocular pressure-lowering drugs at 1wk, 1 and 3mo after surgery in the two groups were significantly lower than those before surgery(all P<0.05), but there was no significant difference between the two groups(all P>0.05). The visual acuity at 1wk, 1 and 3mo after surgery of patients in the combined group was significantly better than that in the simple group(P<0.01). During the follow-up period, the incidence of anterior chamber hemorrhage and transient hypertension in the combined group was significantly lower than that in the simple group(P<0.05).

CONCLUSION: Both suture-guided GATT combined with cataract phacoemulsification and suture-guided GATT are effective treatment for POAG, however, suture-guided GATT combined with phacoemulsification has a lower incidence of anterior chamber hemorrhage and transient ocular hypertension.

Abstract:AIM: To investigate the risk factors associated with neovascular glaucoma(NVG)after pars plana vitrectomy(PPV)for proliferative diabetic retinopathy(PDR).

METHODS: The PDR patients who received 23G PPV treatment at Shenyang He Eye Specialist Hospital from October 2015 to September 2020 and were followed up for at least 12mo with complete data were retrospectively collected. The patients were divided into two groups according to the occurrence of NVG during follow-up. The preoperative and intraoperative variables between two groups were compared. The cumulative hazard ratio for NVG was evaluated.

RESULTS: A total of 151 PDR patients(169 eyes)with a mean follow-up of 18.07±12.55(1～79)mo were included, of which 30(17.8%)eyes developed NVG, the mean time of occurrence was 6.27±4.01(1～17)mo, and 50%(15 eyes)of NVG occurred within 5mo after vitrectomy. The cumulative hazard ratios of NVG at postoperative 3, 6 and 12mo were 4.8%, 12.6% and 18.1%, respectively. Multivariate logistic regression analysis showed that preoperative best corrected visual acuity(OR=3.077, 95%CI: 1.203～7.869, P=0.019), preoperative iris rubeosis(OR=7.897, 95%CI: 1.313～47.498, P=0.024), and contralateral NVG(OR=22.108, 95%CI: 1.562～312.861, P=0.022)were risk factors with the occurrence of NVG, while the number of intraoperative retinal laser photocoagulation(OR=0.772, 95%CI: 0.666～0.893, P=0.001)was the protective factor with the occurrence of NVG.

CONCLUSIONS: The incidence of NVG in PDR eyes after PPV was 17.8%, of which 50% occurred within 5mo after surgery. PDR eyes with poor baseline visual acuity, iris rubeosis, and contralateral NVG are prone to postoperative NVG, and sufficient intraoperative retinal laser photocoagulation has a certain protective effect. PDR eyes after PPV should be closely followed up for 1a.

Abstract:AIM: To compare the effectiveness and complications of treating rhegmatogenous retinal detachment(RRD)with foldable capsule body(FCB)and scleral buckling(SB).

METHODS: The clinical data of 81 patients(82 eyes)with RRD who underwent surgery at our hospital from March 2019 to April 2022 were retrospectively analyzed. The differences in retinal reattachment rate, best-corrected visual acuity, the absorption of subretinal fluid, postoperative discomfort and incidence of complications between the two treatments were compared.

RESULTS: The retinal reattachment rate was 96% in the FCB group and 92% in the SB group, with no significant difference between the two groups(P>0.05). The best corrected visual acuity of the affected macular eyes was different in the both groups(P<0.01). Both groups effectively promoted the absorption of subretinal fluid. The operation time of FCB group was 16.50(12.75, 25.00)min, while it was 38.00(36.25, 41.75)min in the SB group(P<0.001). Patients in the FCB group also had significantly lower eyelid swelling and pain symptoms than those in the SB group(P<0.001). The visual analogue scale(VAS)score at 1d after operation was 1.00(0.00, 2.00)in the FCB group and 3.00(2.00, 3.00)in the SB group(P<0.001).

CONCLUSION: FCB is a safe and effective surgical method to treat RRD that can alleviate patient's pain. Furthermore, FCB has a significantly shorter operation time and milder postoperative adverse reactions than SB.

Abstract:AIM: To investigate the effect of intravitreal ranibizumab injection on ocular parameters in the treatment of retinopathy of prematurity(ROP), and analyze its relationship with birth weight(BW)and postmenstrual age(PMA).

METHODS: A total of 98 premature infants who received routine ROP screening at Northwest Women's and Children's Hospital from January 1, 2016 to January 31, 2022 were selected, and they were divided into ROP group(49 cases)and non-ROP group(49 cases)according to the results of Retcam3 fundus screening. All children in ROP group were treated with intravitreal ranibizumab injection, with an average PMA of 38.02±3.03 weeks. The ocular parameters were measured at the PMA of 0 month(40 weeks±14d), 3 months(52 weeks±28d)and 6 months(64 weeks±28d), respectively.

RESULTS: There was no difference in axial length(AL), anterior chamber depth(ACD), lens thickness(LT), vitreous length(VL)and central corneal thickness(CCT)between ROP group and non-ROP group at the PMA of 0 month(P>0.05); At the PMA of 3 and 6 months, ACD in ROP group was higher than that in non-ROP group, and LT was lower than that in non-ROP group(P<0.05); at the PMA of 6 months, AL and VL in ROP group were lower than those in non-ROP group(P<0.05). AL, ACD and VL were positively correlated with PMA in ROP group and non-ROP group, while CCT was negatively correlated with PMA; there was a positive correlation between LT and PMA in children without ROP. There was no correlation among LT, BW and PMA in ROP group.

CONCLUSION: The ocular development of children with early ROP(PMA 0～6 months)treated by intravitreal ranibizumab injection is slower than that of premature infants without ROP, and BW and PMA are the main influencing factors of ocular parameters of premature infants.

Abstract:AIM: To investigate the effect of orbital decompression on the central macular choroidal thickness(CMCT)in patients with thyroid-associated ophthalmopathy(TAO).

METHOD: Prospective clinical studies. A total of 29 TAO patients(42 eyes)treated in our department from January 2021 to January 2022 were analyzed, and they were divided into 20 cases(30 eyes)in the moderate and severe group and 9 cases(12 eyes)in the extremely severe group. Both groups of patients received orbital decompression, and the changes of CMCT, visual acuity, intraocular pressure, exophthalmos, and clinical activity score(CAS)at 3 and 6mo before and after surgery were compared between the two groups.

RESULTS: All patients completed follow-up. The CMCT, exophthalmos, intraocular pressure, and CAS of the extremely severe group at 3 and 6mo were 355.13±15.59 and 339.61±13.17μm, 19.33±2.23 and 17.83±1.70mm, 18.86±3.05 and 18.09±1.37mmHg, 3.75±0.87 and 2.42±1.00 points, respectively. The moderate and severe group was 325.00±10.48 and 321.04±11.34μm, 16.07±1.74 and 15.6±1.98mm, 16.65±2.04 and 16.03±2.3mmHg, 1.50±0.51 and 1.43±0.50 points, and there was differences with those before operation(extremely severe group: 396.46±17.61μm, 22.00±2.3mm, 21.85±2.82mmHg, 5.33±1.44 points; moderate and severe group: 335.77±11.60μm, 19.07±1.84mm, 18.89±3.06mmHg, 1.63±0.49 points; all P<0.001). The best corrected visual acuity(LogMAR)before surgery was 0.64±0.22 in the extremely severe group, and 0.43±0.20 and 0.34±0.15 at 3 and 6mo after operation, respectively, which were different from those before surgery(all P<0.001)

CONCLUSION: Orbital decompression can effectively reduce CMCT, intraocular pressure and exophthalmos in TAO patients, relieve orbital vein stasis, and effectively improve vision and reduce mobility in patients with extremely severe disease.

Abstract:AIM: To explore the effects of anti-vascular endothelial growth factor(VEGF)agents(Conbercept)before pars plana vitrectomy(PPV)on inflammatory cytokine levels of patients with proliferative diabetic retinopathy(PDR).

METHODS: A total of 49 patients(49 eyes)who diagnosed with PDR at the First Affiliated Hospital with Nanjing Medical University from June 2017 to January 2018 were recruited and randomly divided into two groups. A total of 25 cases(25 eyes)who did not receive intravitreal injection before PPV were included in no-intravitreal injection of Conbercept(IVC)group, and 24 cases(24 eyes)who received IVC 5～7d before PPV were included in IVC group. The vitreous samples were collected from all the patients at the start of PPV. Levels of VEGF-A, monocyte chemotactic protein-1(MCP-1)and inflammatory cytokines in the vitreous humor were measured using Luminex technology.

RESULTS: Compared with the no-IVC group, the level of VEGF-A decreased significantly(P<0.001), the concentration of IL-6(P=0.004), IL-8(P=0.002), IL-18(P=0.04)and TNF-α(P=0.03)increased remarkably in the IVC group. The other inflammatory cytokines in the vitreous humor showed no significant difference between the IVC and no-IVC groups.

CONCLUSION: IVC before PPV can effectively decrease the concentration of VEGF-A, but had limited influence on the level of inflammatory cytokines in the vitreous humor of patients with PDR.

Abstract:AIM: To explore the clinical application value of analysis system for ultrasound biomicroscopy(UBM)images of anterior chamber angle(ACA)based on deep learning algorithm.

METHODS: A total of 4 196 UBM images were obtained from 675 patients(1 130 eyes)at the Eye Center of Renmin Hospital of Wuhan University from January 2021 to June 2022 were collected to build an image dataset. Using Unet++network to automatically segment ACA tissue, a support vector machine(SVM)algorithm was developed to automatically classify opening and closing of chamber angle, and an algorithm to automatically locate the sclera spur and measure ACA parameters was developed. Furthermore, a total of 631 UBM images of 127 subjects(221 eyes)at Huangshi Aier Eye Hospital and 594 UBM images of 188 subjects(257 eyes)at Zhongnan Hospital of Wuhan University were selected to evaluate the performance of the system under different environments.

RESULTS: The accuracy of the analysis system constructed in this study for chamber angle opening and closing was 95.71%. The intra-class correlation coefficient(ICC)values of all ACA angle parameters were greater than 0.960. ICC values of all ACA thickness parameters were greater than 0.884. The accurate measurement of ACA parameters depended in part on the accurate location of the scleral spur.

CONCLUSION: The intelligent analysis system constructed in this study can accurately and effectively evaluate ACA images automatically and is a potential screening tool for the rapid identification of ACA structures.

Abstract:Since the advent of artificial intelligence(AI), it has been increasingly applied and rapidly developed in various fields. In the field of medicine, image features can be automatically extracted and the performance of feature learning and classification can be completed with the help of AI. In the field of ocular fundus disease, AI can give a diagnosis of age-related maculopathy by analyzing and identifying fundus photography and optical coherence tomography with an accuracy rate similar to that of ophthalmologists. In the future, AI may assist physicians in making a diagnosis of age-related macular degeneration, aid basic hospital in screening and curb its progression in the early stage of the disease. However, the technique has problems such as uncertain model recognition performance, opaque operation process, and excessive amount of clinical data required, which still cannot be widely used in the clinic. In recent years, a lot of research has been done in China in the application of deep learning with AI to assist diagnosis of ophthalmic diseases, and the results show that AI combined with imaging analysis of ophthalmic diseases has such characteristics as objectivity, efficiency and accuracy. In this article, studies on deep learning in the auxiliary diagnosis of age-related maculopathy are reviewed, and the progress on its application and the limitations that exist are analyzed, so as to provide more information on the use and extension of AI in this disease.

Abstract:AIM: To investigate the effect of repeated intravitreal injection of ranibizumab and aflibercept on corneal nerve of patients with macular edema.

METHODS: A total of 64 patients(64 eyes)enrolled in our hospital from June 2021 to June 2022 were treated with intravitreal injection of anti-vascular endothelial growth factor(VEGF). There were 20 cases(20 eyes)of diabetic macular edema, 19 cases(19 eyes)of wet age-related macular degeneration and 25 cases(25 eyes)of retinal vein occlusion. Corneal confocal microscope was used to collect images of corneal subbasal nerve plexus before injections and at 1mo after each intravitreal injection based on 3+pro re nata(PRN)treatment regimen. Furthermore, the length and density of corneal nerve were measured.

RESULTS: There was no significant difference in corneal nerve density of patients injected with aflibercept between pre-injection and post-injection(P>0.05), while the corneal nerve length after 2^nd and 3^rd injections was lower than that of pre-injection(all P<0.01). There were no significant changes in corneal nerve density and length in patients with intravitreal injections of ranibizumab(all P>0.05), and there was no significant differences in corneal nerve density and length after 3 injections of the two drugs(all P>0.05).

CONCLUSION: Repeated intravitreal anti-VEGF drug may affect corneal nerve to some extent. For patients who need repeated intravitreal injections of anti-VEGF, attention should be paid to the changes of corneal nerves.

Abstract:AIM: To compare the efficacy and safety of intravitreal injection of aflibercept combined with posterior sub-fascial injection of triamcinolone acetonide in the treatment of wet age-related macular degeneration(ARMD)with poor response to anti-vascular endothelial growth factor drugs.

METHODS: Retrospective cohort study. From June 2018 to May 2020, a total of 60 patients(60 eyes)with refractory ARMD who had poor response to the treatment of anti VEGF drug ranibizumab were randomly divided into the control group of aflibercept and the observation group of triamcinolone acetonide combined with aflibercept, with 30 patients(30 eyes)in each group. Once a month, the patients in the two groups received intravitreal injection of aflibercept alone or intravitreal injection of aflibercept combined with posterior sub-fascial injection of triamcinolone acetonide for three consecutive times. The changes of best corrected visual acuity(BCVA), central macular thickness(CMT)and intraocular pressure were reviewed before injection and 1, 3 and 6mo after the third injection.

RESULTS: The BCVA and CMT of the two groups were significantly improved 1, 3 and 6mo after the injection of the drug(P<0.05). The mean intraocular pressure in the combined group was higher at 1mo after treatment than before, but it still within the normal range. There was a significant difference in intraocular pressure between the two groups(17.50±4.60 vs. 18.30±3.73mmHg, P<0.05).

CONCLUSION: Triamcinolone acetonide injection under the posterior fascia of the eyeball combined with intravitreal injection of aflibercept in the treatment of wet ARMD can effectively reduce macular edema and improve vision, which is more safe and reliable.

Abstract:AIM: To comparatively analyze the efficacy and safety between 25-gauge(25G+)and 27G+ micro-invasive vitrectomy for the treatment of vitreoretinal diseases.

METHODS: The clinical data of 89 cases(89 eyes)of vitreoretinal disease who received vitrectomy at our hospital from March 2019 to April 2022 were retrospectively analyzed. They were divided into two groups according to surgery. A total of 45 cases(45 eyes)who received 25G+ micro-invasive vitrectomy were included in group A, and 44 cases(44 eyes)who received 27G+ micro-invasive vitrectomy were included in group B. Vitrectomy time, operation time, preoperative and postoperative best corrected visual acuity(BCVA), intraocular pressure, subjective comfort evaluation results and complications of the both groups were analyzed.

RESULTS: There were no differences in vitrectomy time of the two groups(P>0.05), while the operation time of group B was shorter than that of group A(35.50±14.27min vs. 41.73±14.25min, P=0.042). The postoperative BCVA of the two groups were better than that before operation(P<0.05), while there was no significant difference between two groups(P>0.05). The postoperative intraocular pressure of the two groups was lower than that before operation(P<0.05), and it was slightly lower than group B at 1 and 7d after operation(P<0.05). As for the subjective comfort evaluation results, the scores of group A was higher than that of group B at 1d after operation(6.13±1.20 vs. 3.45±1.17, P<0.001); and there were no differences between two groups at 7d after operation(2.18±1.01 vs. 1.93±0.87, P=0.215). During the follow-up, 7(16%)eyes of incision leakage occurred in group A, of which 6(13%)eyes were transient hypotony, and 10(22%)eyes had conjunctival chemosis. In the group B, there was no incision leakage and transient hypotony, while conjunctival chemosis occurred in 2(4%)eyes at 1d after operation.

CONCLUSION: Both 25G+ and 27G+ micro-invasive vitrectomy can improve visual acuity, stabilize intraocular pressure and be safe in patients with vitreoretinal disease. However, 27G+ micro-invasive vitrectomy has less leakage, stable intraocular pressure, shorter operation time and lower incidence of conjunctival chemosis.

Abstract:AIM: To investigate the efficacy and safety of dacryocystorhinostomy(DCR)through nasal endoscope with extended bone window and high ostomy in the treatment of chronic dacryocystitis.

METHODS: Retrospective clinical study. A total of 50 patients(59 eyes)diagnosed with chronic dacryocystitis in our hospital from January 2018 to January 2020 were selected. They were divided into two groups according to the operation method, with 23 cases(29 eyes)in the simple stoma group and 27 cases(30 eyes)in the improved group. Patients in the simple stoma group were treated with transnasal endoscopic flat middle turbinate axillary DCR(simple stoma), and patients in the improved group were treated with transnasal endoscopic extended bone window with high-level stoma DCR. The total clinical efficiency, postoperative complication rate and satisfaction of the two groups were compared.

RESULTS: The effective rate of the simple stoma group was 79% at 12mo after surgery, while that of the improved group was 97%(P=0.039). The total incidence of complications in the simple stoma group was 28%, while that in the improved group was 7%(P=0.042). The satisfaction rate of the simple stoma group was 65%, while that of the improved group was 93%(P=0.030).

CONCLUSION: The treatment of chronic dacryocystitis with transnasal endoscopic extended bone window and high-level ostomy DCR further improved the efficiency of surgery and reduced the incidence of complications.

Abstract:AIM: To explore the difference of tear film stability among different lipid layer thickness.

METHOD: A total of 194 dry eye patients(384 eyes)admitted to our hospital from June 2020 to December 2021 were enrolled in this study. The tear meniscus height, the first tear film break-up time and lipid layer thickness were measured by corneal topographer. The tear meniscus height and the first tear film break-up time among different lipid layer thickness were compared and the correlation between them was analyzed.

RESULTS: The included patients(384 eyes)were divided into lipid rich group(49 eyes), lipid balance group(27 eyes), slight lipid deficiency group(266 eyes)and significant lipid deficiency group(42 eyes)according to the lipid layer thickness. The differences of the tear meniscus height were statistically different(P=0.022), while the differences of the first tear film break-up time were not statistically different(P=0.322). The lipid layer thickness was positively correlated with tear meniscus height(r_s=0.143, P=0.006). There was no correlation between lipid layer thickness and the first tear film break-up time(r_s=-0.090, P=0.083), nor was there correlation between tear meniscus height and the first tear film break-up time(r_s=0.038, P=0.460).

CONCLUSION: There was no significant difference in tear film stability in dry eye patients with different lipid layer thickness.

Abstract:AIM:To explore the influence factors of the treatment zone diameter(TZD)and its correlation with axial length growth(ALG)after Paragon CRT orthokeratology.

METHODS: Retrospective clinical study. The data of 226 myopic patients(226 eyes)wearing Paragon CRT orthokeratology from April 2020 to September 2022 were collect. The correlated factors of TZD after wearing lens for 1mo, and the relationship between the overlapping treatment zone/ pupil area ratio and the ALG after wearing lens for 1a were analyzed.

RESULTS: After wearing lens for 1mo, the TZD was negatively correlated with central corneal thickness(CCT)and positively correlated with the flat corneal eccentricity. After wearing lens for 1a, the ALG of the small TZD group(0.25±0.18mm)was significantly smaller than that of the large TZD group(0.34±0.24mm, P=0.002), and the ALG of the small area ratio group(0.24±0.19mm)was significantly smaller than that of the large area ratio group(0.35±0.23mm,P<0.001). Age and overlapping treatment zone area/pupil area ratio were significantly associated with the ALG in multivariate linear regression(all P<0.05).

CONCLUSION: The wearers with thicker CCT and smaller flat corneal eccentricity usually had smaller TZD, and both the TZD and the overlapping treatment zone area/pupil area ratio were correlated with the ALG.

Abstract:AIM: To explore the characteristics of astigmatism in preschool children before, during and after the COVID-19 epidemic, so as to provide a reference for further prevention and control of children's vision.

METHODS: In the consecutive four years from January 2018 to December 2021, a retrospective analysis of vision data was conducted on 2 273 preschool children(4 546 eyes)younger than 4 years old who participated in children's vision screening test in Baiyun district, Guangzhou. They were divided into 1-year old group(ages<1-year old, 420 cases), 2-year old group(1-year ≤ ages <2-year, 543 cases), 3-year old group(2-year ≤ages <3-year, 614 cases), and 4-year old group(3-year ≤ ages<4-year, 696 cases)according to ages. The analysis included astigmatic degrees of children's eyes as well as their conditions of astigmatism.

RESULTS: In 2018, the astigmatic degrees of the both eyes of 1-year-old group were higher than those of other groups(P<0.05). The binocular astigmatic degrees of the preschool children in four groups were obviously higher in 2020 than 2019(P<0.05), while they were significantly decreased in 2021 when compared with 2020(P<0.05). From 2019 to 2020, the increase of astigmatic degrees of the right eye is more considerable than the left eye of preschool children in those four groups(P<0.001). Furthermore, the morbidity of astigmatism basically echoes with the changing tendency of astigmatic degrees from 2018 to 2021.

CONCLUSIONS: Preschool children in Baiyun district, Guangzhou, have the highest degree of astigmatism and the fastest progression rate within 1 year old. Before COVID-19 epidemic, the changes in astigmatism and prevalence were relatively stable; during COVID-19 epidemic, the astigmatism and prevalence increased significantly and the astigmatic degrees of right eye increased more than that of the left eye; after the normalization of epidemic prevention and control, the astigmatism and prevalence decreased significantly.

Abstract:AIM: To analyze the strabismus surgery situation of adolescents and children in Yunnan province.

METHODS: A retrospective analysis was conducted on medical records data of 3 068 adolescents and children who received strabismus surgery at Affiliated Hospital of Yunnan University from January 2017 to December 2021. The analysis included gender, constituent ratio of age, distribution of strabismus types and combination with other ocular diseases, etc.

RESULTS: Among the included patients, 52.12% were males, and 47.88% were females. Preschool patients(1 to 6 years old)accounted for 32.89%, primary pupils(7 to 12 years old)accounted for 45.89% and high school students(13 to 18 years old)accounted for 21.22%. Exotropia accounted for 63.17% of the total strabismus, of which intermittent exotropia was the most common type. Esotropia accounted for 19.69%, and concomitant esotropia was the most common type. The special type of strabismus accounted for 17.14%, and A-V syndrome and dissociative vertical deviation(DVD)were the most common types. Strabismus combined with ametropia accounted for 61.02% and amblyopia accounted for 10.89%. A few patients also combined with other eye diseases.

CONCLUSION: In Yunnan province, intermittent exotropia was the most common type of strabismus among adolescents and children. Some patients combined with other ocular diseases.

Abstract:AIM: To investigate the differences in squint angle measured by right angle prism and isosceles angle prism.

METHODS: Case control study. A total of 176 cases of concomitant strabismus admitted to our hospital from June 2021 to April 2022 were selected, among which 79 cases were concomitant esotropia and 97 cases were concomitant exotropia. The squint angle of all patients was measured respectively by alternating cover right angle prism and isosceles angle prism.

RESULT: For patients with concomitant esotropia, the right angle prism degree was 49.167^△±13.573^△ and the isosceles angle prism degree was 38.250^△±10.756^△ (P<0.01), with a difference of 10.917^△±3.752^△; the measurement of right angle prism converted to circular degree was 19.096°±2.456°, and the isosceles angle prism value was 20.847°±5.364°(P<0.05), with a difference of 2.443°±2.702°. For patients with concomitant exotropia, the right angle prism degree was 51.875^△±13.567^△, and the isosceles angle prism degree was 40.492^△±11.753^△ (P<0.01), with a difference of 11.383^△±4.783^△; the measurement of right angle prism converted to circular degree was 19.589°±2.521°, and the isosceles angle prism value was 21.947°±5.864°(P<0.01), with a difference of 3.200°±3.077°. There was no significant statistical difference in the differences of the two prism degree and the circular degree for concomitant esotropia and concomitant exotropia(P>0.05).

CONCLUSIONS: The squint angle measured by different shaped prisms is different. The degree measured by right angle prism is larger than that by isosceles angle prism.