Objective To observe the subfoveal choroidal thickness (SFCT) in eyes of patients with diabetic macular edema (DME).Methods Twenty patients (32 eyes) with DME were enrolled in this crosssectional observational study.The patients included 12 males and eight females,with a mean age of (47.3± 10.2) years.All the patients were examined documenting best corrected visual acuity (BCVA),spectraldomain optical coherence tomography (OCT) and ophthalmological examination.According to OCT DME morphology,samples are divided into diffuse macular edema,cystoid macular edema,serous retinal detachment and hard exudate groups.The SFCT was measured by a Cirrus HD-OCT with enhanced depth imaging (EDI) and was compared with the average SFCT (286.84 ± 28.80) μm of same age group.Correlation between SFCT and age,diopter,diabetic duration,fasting blood glucose,BCVA and central retinal thickness were analyzed by Pearson Analysis.SFCT of different DME types were analyzed by ANOVA Analysis.Results The mean SFCT of 32 eyes was (223.81±43.74) μm (ranging from 120.50 to 361.50 μm),which was lower by 63.03 μm (95％ confidence interval,-78.80 to-47.26 μm,P＜0.01)from normal SFCT.SFCT was independent of age (r=0.124),diopter (r=0.277),diabetic duration (r=0.286),fasting blood glucose (r=0.408),BCVA (r=0.087),and central retinal thickness (r=0.036).There was no significant difference of SFCT between different DME types (F =0.042,P ＞ 0.05).Conclusion SFCT is thinner in eyes with DME as compared to normal eyes of the same age.

Objective To observe the expression of vascular endothelial growth factor receptor-1 (VEGFR-1) and VEGFR-2 in hypoxic chorioretinal endothelial cells of monkeys (RF/6A),and to evaluate the effect of minocycline.Methods RF/6A was cultured and divided into four groups:control group,hypoxia group,hypoxia and low dose of minocycline group (0.5 μmol/L),hypoxia and medium dose of minocycline group (5 μmol/L),and hypoxia and high dose of minocycline group (50 μmol/L).Real-time reverse transcription-polymerase chain reaction (RT-PCR) and immunohistopathological staining were used to measure the mRNA and protein expression of VEGFR-1 and VEGFR-2,respectively.Results RT-PCR showed that the expression of VEGFR-1 mRNA did not vary significantly between groups (F24 h =0.17,F48 h =1.53,F72 h =2.04; P＞0.05).Compared with hypoxia group,the expression of VEGFR-2 mRNA in all minocycline treated groups were significantly down-regulated (low minocycline,medium minocycline,high minocycline:t=4.69,20.16,17.12; P＜0.001).The immunohistopathological study showed the cells with positive staining of VEGFR-1 can be observed in all groups,and the staining was relatively weak and mainly located in cell membrane and cytoplasm.The optical density value analysis showed that the protein expression of VEGFR-1 did not vary significantly between groups at all time points(F24 h =0.251,F48 h=0.340,F72 h =0.589; P＞0.05).The VEGFR-2 positive staining cells were also observed in all groups,and the staining was relatively high.Brown staining particles of VEGFR-2 were observed in the cell membrane with minor staining particles in cytoplasm.The staining density of VEGFR-2 was significantly higher in hypoxia group than control group.Compared with the hypoxia group,the protein expression of VEGFR 2 in minocycline treated groups was significantly lower (F24 h =19.147,F48 h =14.893,F72 h =11.984; P＜0.05).Conclusion The expression of VEGFR-2 is up-regulated in RF/6A,and minocycline somewhat shows an inhibition effect.

Diabetic macular edema (DME) is a common ocular complication of diabetes patients.It mainly involve macular which is closely related with visual function,thus DME is one of the major reasons causing visual impairment or blindness for diabetes patients.How to reduce the visual damage of DME is always a big challenge in the ophthalmic practice.In the past three decades,there are tremendous developments in DME treatments,from laser photocoagulation,anti-inflammation drugs to anti-vascular endothelial growth factor therapy.However,the mechanism of DME development is not yet completely clear; every existing treatment has its own advantages and weaknesses.Therefore DME treatment still challenges us to explore further to reduce the DME damages.

The pathogenesis of diabetic retinopathy is complicated.The vast network of multiple factors including unifying mechanism,inflammatory reaction,neuron degeneration and metabolic memory of glucose,and the four established pathogenic molecular pathways are hotspots of mechanism research for diabetic retinopathy.Nevertheless,these researches may be only one corner of the iceberg of DR mechanism,and we still face enormous challenges in DR mechanism research.Collaboration with multiple disciplines to study the relationship between DR and diabetes and other systemic diseases,search novel therapy targets may increase the result in an unexpected windfall for DR basic research.

The pathogenesis of polypoidal choroidal vasculopathy (PCV) is still controversial.More evidence of clinical and basic research is needed to distinguish PCV from an independent disease to a subtype of age-related macular degeneration.Not only that,there are also many puzzles in the diagnosis,treatment options and prognosis of PCV.In addition to these common problems,we also face a large population with risk factors,a large number of PCV patients with multiple and complex challenges in China.There is a long way to go to reduce the damage effects of PCV on visual function.To fulfil this goal,we need make full use of the huge resources of PCV patients and turn these challenges into opportunities,and contribute the improvement of diagnosis and better understanding of PCV pathogenesis.

Objective To observe the imaging features of branching vascular network (BVN) in polypoidal choroidal vasculopathy (PCV).Methods Eighty PCV patients (90 eyes) were enrolled in this study.The patients included 58 males and 22 females.The age was ranged from 49 to 85 years,with a mean age of 61.4 years.All the patients were examined for fundus photography,fundus fluorescein angiography (FFA),indocyanine green angiography (ICGA) and optical coherence tomography (OCT).The fibrovascular retinal pigment epithelium detachment (PED) was defined as a well-demarcated subretinal heterogeneous plaque with increasing fluorescence on FFA.The late lichenoid hyperfluorescent plaque was defined as a well-demarcated lichenoid hyperfluorescent plaque on late phase ICGA.The double-layer sign on OCT was defined as a wide range of shallow PED from Bruch membrane.Results BVN were found on early ICGA in 76 eyes among the 90 eyes (84.4％).Among these 76 eyes,18 eyes (23.7％) demonstrated the subretinal reddish-orange branches corresponding to BVN.Fifty-six eyes (73.7％) demonstrated all or part of the BVN on early FFA.Three eyes (3.9％) demonstrated branching transmitted fluorescence corresponding to BVN throughout the FFA.Seventy-three eyes (96.1％) were manifested by occult choroidal vascularization on FFA,and 21 eyes (27.6％) of them were fibrovascular PED.Among the 76 eyes with BVN,all BVN appeared earlier than polypoidal lesions on ICGA.Polypoidal lesions located on the terminal of BVN in 62 eyes (81.6％).Sixty-nine eyes (90.8％) on ICGA demonstrated the late lichenoid hyperfluorescent plaque,whose area was equal to or greater than the area of BVN shown on early ICGA.Seventy-two eyes (94.7％) had the double layer sign.Among these 72 eyes,15 eyes (20.8％) had lumen like structure within the double-layer sign.Sixty-five eyes (90.3％) had punctate and linear hyperreflectance within the double-layer sign.Two eyes (2.8％) demonstrated a hyporeflective short segment and a gap of Bruch membrane on OCT corresponding to the origin of the BVN.Sixty-three eyes (87.5％) had an area of double-layer sign that matched the area of late lichenoid hyperfluorescent plaque on ICGA.Conclusions BVN in PCV can be noted as reddish-orange branches on fundus examination.Most of the BVN are shown as early branching transmitted fluorescence but collectively an occult choroidal vascularization on FFA,as lichenoid hyperfluorescent plaque on late ICGA,and as double-layer sign on OCT whose area matches late lichenoid hyperfluorescent plaque.

Objective To observe the clinical features of late-onset cone dystrophy (LOCD).Methods Eleven patients (15 eyes) of LOCD were enrolled in this study.The patients included 7 males and 4 females.The age was ranged from 50 to 79 years,with a mean age of 60.2 years.There was no obvious photophobia and hemeralopia.The visual acuity was less than or equal to 0.05 in 4 eyes,0.06-0.2 in 5 eyes,0.3-1.0 in 6 eyes.Visual acuity,slit lamp microscope,indirect ophthalmoscopy,flash electroretinogram (FERG) and multifocal electroretinograms (mfERG) were examined for all patients,fundus fluorescein angiography (FFA) for 11 eyes,optical coherence tomography (OCT) and chromoptometry for 6 eyes.Results There were 6 eyes with red/green color blindness,2 eyes with color weakness.Normal fundus was found in 11 eyes,while derangement of macular pigment epithelial in 4 eyes.FFA results showed that there were 5 eyes with normal fundus,4 eyes with blocked fluorescent spots,2 eyes with oval macular atrophy.FERG results showed that in cone response,the amplitude was lower in 6 eyes (including mild decrease in 4 eyes,moderate decrease in 1 eye and severe decrease in 1 eye) ; both in cone and rod response,the amplitude were lower in 9 eyes.mfERG results showed that central part of the cone (less than 7 degree from the center) was damaged in 5 eyes,both central and peripheral part (outside of 7 degree) of the cone were damaged in 10 eyes.OCT results showed that pigment derangement in 3 eyes,fovea was normal in 8 eyes,thinned in 5 eyes (foveal thickness was 83-111 μm).Conclusions The fundus manifestations of LOCD patients are variable,from normal fundus to oval macular atrophy.FERG is abnormal,which mainly in cone response at early stage and both in cone and rod response at late stage.Central part and (or) peripheral part of the cone are abnormal by mfERG.

There are many topics in clinical studies of diabetic retinopathy (DR).The current hot topics include the relationship between DR and systemic diseases,major factors for initiation and progression of DR,early DR screening strategies,DR prevention strategies and how to improve the therapeutic effects of DR.However,due to the complexity of DR pathogenesis,multiple risk factors,long cycle of DR prevention and control,it is difficult to exclude all the confounding factors in the DR clinical research.From the long-term perspective,delaying the occurrence and progression of DR and establishing an efficient and practical prevention and control system is the focus of the future DR research in China.

Objective To compare the outcomes of 23G and 25G plus (25G+) vitrectomy in treatment of proliferative diabetic retinopathy (PDR).Methods This is a prospective randomized study.Fifty-seven PDR patients (75 eyes) with symptoms requiring vitrectomy were randomly divided into 23G vitrectomy group (30 patients,39 eyes) and 25G+ vitrectomy group (27 patients,36 eyes).Visual acuity,intraocular pressures,ophthalmoscopy,B-scan ultrasound was examined before surgery.The follow-up period was 10.0 (23G group) and 8.5 months (25G+ group) respectively.Intraoperative complications,operation time,postoperative visual acuity,intraocular pressure,postoperative complications and postoperative ocular conditions were analyzed.Results The mean surgical times were (53.35± 7.42)minutes and (49.16±5.17) minutes in 23G and 25G+ group respectively,and the difference was significant (t=4.37,P＜0.05).Iatrogenic injuries occurred in 11 eyes (28.21％) and 5 (13.89％) eyes in 23G and 25G + group respectively,and the difference was significant (x2 =4.93,P＜0.05).The postoperative visual acuity of 23G and 25G+ group were improved compared to before surgery (x2=16.81,18.29; P＜0.05).At last follow-up,there was 25 eyes and 24 eyes with visual acuity ≥ 0.05 in 23G and 25G+ groups respectively,and the difference was not significant (x2 =0.13,P＞0.05).Hypotony was detected in 7 and 3 eyes at the third postoperative day in 23G and 25G+ group respectively,and the difference was significant (x2 =5.67,P＜0.05).Conclusion 25G+ vitrectomy is a safe and effective treatment for PDR with shorter surgery time and fewer surgical complications.

Objective To investigate the effects of leptin on the oxidative damage in human retinal pigment epithelial (RPE) cells.Methods Human RPE cells (ARPE-19) were cultured in vitro,and randomly divided into control group and insulin resistance group.RPE cells were treated with 0,10,100 ng/mL leptin for 24,48,72 hours respectively.Then the levels of reactive oxygen species (ROS) expression in RPE cells were detected by 2',7'-dichlorofluorescin-diacetate (DCFH-DA),and the levels of 8-hydroxy-2′-deoxyguanosine (8-OHdG) expression in RPE cells were observed by immunocytochemistry (ICC),and the levels of human 8-oxoguanine DNA glycosylase 1 (hOGG1) expression in lysate were measured by Western blot.Results After 24,48,72 hours,the level of ROS (Control group:F=37.136,37.178,49.634; P＜0.05.Insulin resistance group:F=9.822,28.881,71.150;P＜0.05),8-OHdG (Control group:F =88.643,390.920,1039.276; P ＜ 0.05.Insulin resistance group:F =273.311,299.155,82.237;P＜0.05) and hOGGl (Control group:F=470.062,1073.113,295.456;P＜0.05.Insulin resistance group:F =240.032,592.389,527.760 ; P＜0.05) expression increased significantly with the increase of leptin concentration in control group and insulin resistance group.Under the same leptin concentration,the level of 8-OHdG has a trend that it was higher in the insulin resistance group than the control group.After 24 hours,the difference of hOGGl expression between control group and insulin resistance group was not significant (F=23.392,P＞0.05).After 72 hours,the level of hOGGl expression was significantly higher in the insulin resistance group than the control group (F=129.394,P＜0.05).The level of hOGGl expression was significantly higher at 48 hours than that at 24 hours and 72 hours (P＜ 0.05).Conclusion Leptin could induce the oxidative damage of RPE cells in normal and insulin resistance status.With the increase of leptin concentration and time extended,the degree of oxidative damage and its repair were both increased.The degree of oxidative repair increased with the increase of leptin concentration,but decreased with time extended.