Purpose To estabalish a quantifying model of retinal neovascularization suitable for the study of pathogenesis and therapeutic intervention for the retinal neovascularization． Methods Sixteen one-week-old C57BL/6 mice were exposed to 75% oxygen for 5 days and then to room air and 16 mice of the same age kept in room air as controls.Ink-perfused retinal flatmount was examined to assess the oxygen-induced changes of retinal vessels.The proliferated neovascular response was quantitated by counting the nuclei of endothelial cells of new vessels extending from the retina into the vitreous in 6 mu;m sagittal cross sections． VEGF and bFGF were determined on the cross-sections after immunohistochemcal stain. Results Constriction and closure of the blood vessels were found under the hyperoxia condition,and dilation and proliferation were found under the relatively hypoxia status.There was a mean of 24 neovascular nuclei per cross-section in the oxygen-treated retina and less than 1 nucleus in the control group (P＜0.001).VEGF stain was found ber in the inner retinal layer of oxygen-treated mouse than in that of the controls. Conclusion The quantifying model of retinal neovascularization may fascilitate the further researches of medical intervention and pathogenesis of retinal neovacularization. (Chin J Ocul Fundus Dis，2000，16：213-284)
With the rapid development of fundus imaging technology, it is of great significance to establish a new naming system for neovascular age-related macular degeneration (nAMD) based on the multi-mode imaging. In 2020, an international panel of retina specialists, imaging and image reading center experts, and ocular pathologists reached a consensus after repeated discussions, a new name for nAMD subtype and related lesions was established based on the previous knowledge of fundus fluorescein angiography and pathology, combining indocyanine green angiography, optical coherence tomography and optical coherence tomography angiography with current pathological knowledge, in order to help ophthalmologists to study nAMD. The consensus proposed the term "macular neovascularization" and classified it into type 1, type 2 and type 3. Many lesions related to macular neovascularization, such as pigment epithelial detachment, hemorrhage, fibrosis, rip of retinal pigment epithelium and so on, were named. The new designation will help improve clinical communication between different studies, establish standard definitions and terms between reading centers and researchers, and further promote the understanding and communication of nAMD among ophthalmologists.
Objective To observe the effect of Nodal on the biological behavior of retinal vascular endothelial cells (RF/6A cells) in monkeys with high glucose. MethodsRF/6A cells were divided into normal group, mannitol group, high glucose group, high glucose combined with non-specific small interfering RNA treatment group (HG+NC group), high glucose combined with small interfering Nodal treatment group (HG+siNodal group). The transfection efficiency of siNodal was observed by real-time fluorescence quantitative PCR and western blot protein immunoblotting. The effect of Nodal on the proliferation of RF/6A cells was detected by thiazole blue colorimetry. The effect of Nodal on migration ability of RF/6A cells was detected by cell scratch assay. The effect of Nodal on the formation of RF/6A cell lumen was measured by Matrigel three-dimensional in vitro. The expression of extracellular signal phosphorylated regulated kinase 1/2 (pERK1/2) in RF/6A cells was detected by western blot protein immunoblotting. One-way analysis of variance was used to compare groups. ResultsCompared with HG+NC group, Nodal protein (F=33.469) and mRNA relative expression levels (F=38.191) in HG+siNodal group were significantly decreased, cell proliferation was significantly decreased (F=28.548), and cell migration ability was significantly decreased (F=24.182). The number of cell lumen formation was significantly decreased (F=52.643), and the differences were statistically significant (P＜0.05). Compared with HG+NC group, the relative expression of pERK1/2 protein in HG+siNodal group was significantly decreased, and the difference was statistically significant (F=44.462, P＜0.01). ConclusionsSilencing Nodal expression can inhibit proliferation, migration and tube formation of RF/6A cells induced by high glucose. It may act by inhibiting pERK1/2 expression.
ObjectiveTo assess the occurrence of CNV in patients presenting with flat irregular pigment epithelial detachments (FIPED). MethodsForty-five patients (49 eyes) with FIPED on OCT were enrolled in this retrospective study. There were 25 males (28 eyes) and 20 females (21 eyes). The mean age was 61.022±9.292 years. FFA, ICGA, spectral domain OCT and OCT angiography (OCTA) were performed in all patients during the same period. The FIPED was defined as an irregular elevation of the RPE allowing distinct visualization of Bruch’s membrane on OCT B-scan. The abnormal vascular signals from the deep retinal layer to the choroid layer on OCTA was defined as CNV. The CNV was classified into a type 1 CNV and a type 2 CNV according to the OCT characteristics. The CNV was classified into a typical and occult CNV according to the characteristics of the FFA image. Of all 49 eyes, fundus angiography revealed 18 eyes (36.7%) with CNV, and 31 eyes (63.3%) with no characteristic signs of CNV. FFA examination found that CNV in 8 eyes (classic CNV in 1 eyes, occult CNV in 7 eyes), which confirmed by OCT were type 1 CNV; transmitted fluorescence in 41 eyes. ICGA examination showed that CNV-like hyperfluorescence spots in 18 eyes, suspicious hyperfluorescence spots in late stage in 20 eyes, and choroidal high permeability in 11 eyes, respectively; and 18 CNV eyes were confirmed to be type 1 CNV by OCT. To compare the detection of CNV by OCTA and fundus angiography. ResultsOf the 49 eyes with FIPED, OCTA detected 36 eyes (73.5%) of type 1 CNV, and full or partial strong reflex signals were seen in FIPED; 13 eyes (26.5%) were not associated with CNV, and some strong reflection signals were found in FIPED in 9 eyes, 4 eyes with weak reflection signal. The FFA was examined for 1, 7 eyes of the classic and occult CNV, which confirmed to be type 1 CNV by OCTA. Among the 18 eyes with CNV which detected by ICGA, OCTA also found type 1 CNV. Among the 20 eyes with ICGA’s late suspicious strong fluorescent spots, OCTA showed 17 eyes of type 1 CNV; in 11 eyes with high choroidal permeability, OCTA showed type 1 CNV in 1 eye. Among the 36 eyes with CNV which detected by OCT, there were SRD in 32 eyes, no SRD in 2 eyes and retinal interlamellar cavities in 2 eyes. ConclusionOCTA can detect 73.5% of FIPED eyes with CNV. Compared with traditional fundus angiography, OCTA has a higher detection rate of CNV under FIPED. The FIPED of the internal strong reflection signal has a certain diagnostic value for the type 1 CNV.
Purpose To investigate the roles of vascular endothelial growth factor (VEGF),glutamate and gamma;- aminobutyric acid (GABA) in neovascularization of proliferative diabetic retinopathy (PDR). Methods Vitreous samples were collected from 25 patients (27 eyes)with PDR and 14 patients (14 eyes) with idiopathic macular hole.VEGF levels were determined by ELISA.Amino acids analyses were performed by high-performance liquid chromatography. Results Patients with PDR had significantly higher concentrations of VEGF (median 0.41 ng/ml,quartile 0.54 ng/ml) than controls (median 0.017 ng/ml,quartile 0.01 ng/ml)(Plt;0.001).The levels of glutamate [(11.7plusmn;3.0) mu;mol/L] and GABA [(7.2plusmn;3.9mu;mol/L)] were also higher in patients with PDR than glutamate [(5.8plusmn;0.7) mu;mol/L] and GABA [(3.3plusmn;2.9) mu;mol/L) in controls (Plt;0.05).The glutamate level and GABA level had a significantly positive correlation with VEGF level. Conclusions The increased levels of glutamate and GABA indicate retinal ischemia.The correlations of glutamate and GABA levels with an elevated VEGF level provide biochemical support for ischemi induced neovascularization in patients with PDR.The findings present novel modalities in treatment of PDR. (Chin J Ocul Fundus Dis,2000,16:162-165)
Purpose To evaluate the efficacy of vitreous surgery and endolaser in a series of patients with retinal vein occlusion(RVO)with vitreous hemorrhage,neovascular membranes(NVM) and/or traction retinal detachment(TRD). Methods Clinical records were reviewed on 37 consecutive patients(38 eyes)who underwent vitreous surgery and endolaser for RVO with persistent vitreous hemorrhage,NVM and/or TRD.There were 19 patients(20 eyes)with retinal branch vein occlusion (BRVO)and 18 patients(18 eyes)with central retinal vein occlusion(CRVO). Results NVM and TRD were confirmed during operation in 27 and 23 eyes,respectively.Visual acuity improved postoperatively in 34 eyes(89.5%)including 22 eyes with 0.1 or better vision,and 4 eyes remained unchanged.CRVO group had longer history and less visual improvement after surgery. Conclusions Vitreous surgery and endolaser photocoagulation can improve the outcome in the majority of patients with RVO with vitreous hemorrage,NVM and/or TRD. (Chin J Ocul Fundus Dis,1998,14:3-6)
Objective To evaluate the diagnostic value of Heidelberg retinal angiography(HRA) combined with optical coherence tomography (OCT) to detect neovascularization (CNV) in exudative agerelated macular degeneration (AMD) patients. Methods This is a cross-sectional study of a series of clinical cases. AMD diagnosis was established by international standard vision chart, Slit lamp microscope, direct or indirect ophthalmoscope examination. A total of 50 eyes (42 cases) of exudative AMD received HRA and frequency domain OCT scan. All 50 eyes received fundus fluorescein angiography (FFA) and frequency domain OCT simultaneously, and among them 15 eyes also received indocyanine green angiography (ICGA) at the same time. FFA and ICGA were carried out by conventional methods, CNV was localized by real-time localization technology of frequency domain OCT. In the radial and grid-like section from the areas with b fluorescence, image acquisition settings are 7 mu;m fault for each frame, 30 deg; intervals for radial section, 10 vertical and 10 horizontal scan lines for gridlike section. CNV can be divided into 4 types (typical CNV, partial typical CNV, occult CNV, CNV scarring) according to their boundaries demonstrated in FFA. Based on the features of the OCT images, there were 3 types of integrated image (sub-RPE type, sub-retinal type and mixed type). Results CNV was detected in all 50 eyes. There were 4 eyes (8%) of typical CNV, 11 eyes (22%) of partial typical CNV, 32 eyes (64%, including 27 eyes of RPE detachment and 5 eyes of passive late leakage) of occult CNV and 3 eyes (6%) of CNV scarring. There were 4 eyes (8%) of subRPE type (CNV under the RPE light band) , 16 eyes (32%) of subretinal type(interrupted light band of RPE and choroid capillary layer) and 30 eyes (60%) of mixed type of integrated image. Conclusion The image integration technology of the HRA and frequency domain OCT system provide a valuable tool to classify and measure CNV, which will benefit the clinical treatment of AMD patients.
Objective To observe the therapeutic effect of ultrasonic microbubble combined with bevacizumab (Avastin) on choroidal neovascularization induced by photocoagulation in rabbits.Methods CNV was induced by photocoagulation with argon laser in 30 rabbits (60 eyes).All of the rabbits underwent fundus fluorecein angiography (FFA) 21 days after photocoagulation; 6-8 hours later, 3 rabbits were randomly chosen to be executed to having the immunohistochemical examination.Twenty one days after photocoagulation, 27 rabbits were divided randomly into 3 groups: bevacizumb, ultrasonic microbubble + bevacizumb,and control group; each group has 9 rabbits (18 eyes).The rabbits in control group had no interference treatment; while the rats in bevacizumb and ultrasonic microbubble + bevacizumb group underwent injection with bevacizumb or ultrasonic microbubble + bevacizumb respectively.FFA was performed on all of the rabbits 7,14,and 28 days after photocoagulation to observe the inhibition of CNV; immunofluorecence and Western blot were used to detect the expression of VEGF in retina and choroid.Twentyeight days is the time point to determine the therapeutic efficacy. The expression of VEGF and the results of FFA were the sdandards of the judgement of therapeutic efficacy.Results Proliferaion of CNV to the retinal inner layer and the obvious leakage of fluoresein in the photocoagulation area indicated that the model of CNV was set up successfully. Twenty eight days after injection,obvious fluorescent leakage was found in the control group, and the average fluorescent leakage in bevacizumab group differed much from the control group（t=16.2952，Plt;0.05）; while the difference between ultrasonic microbubble + bevacizumb group and bevacizumab group was also significant (t=4.7955，Plt;0.05) . At the same time point, the expression of VEGF in bevacizumab group detected by immunofluorecent assay and Western blot differed much from the control group (t=7.0327，9.2596；Plt;0.05),and the difference of VEGF between ultrasonic microbubble + bevacizumb group and bevacizumab group was significant（t=2.9724,17.1937；Plt;0.05）. this experiment show that ultrasound combined bevacizumab intravitreal injection of the therapeutic effect of CNV superior to other groups(Plt;0.01).Conclusion Ultrasound microbubble combined with bevacizumab injection may improve the therapeutic effect on CNV by inhibiting the expression of VEGF.
Objective To investigate auto-cortex of crystalline lens-induced neovascular epiretinal membrane（NVERM）by micro-injuring posterior c apsule of crystalline lens. Methods twenty four C57BL/6 mouse between 4-6 weeks were selected, and divided into two groups randomly: auto-cortex of crystalline group and the control group. The auto-cortex of crystalline group was treated by penetrating the posterior capsule of lens and washing out the lens cortex into the mouse vitreous using PBS (phosphate buffered solution), while the control group were injected PBS into vitreous merely. Clinical change s were followed by slit-lamp examination and photograph. The eye balls were enu cleated at the day of 3, 7, 14 and 28 after operation. Both HE and immunohistoch emistry were used to detect the pathological changes. Results postoperative one to three days, 11 of 12 mouse in autocortex of crystalline g roup, lens appear to alba turbid at different levels one after another, and then develop into highdensity chinaware white. Postoperative (po) three days, HE s taining shows cortex of lens debris transmigrated in vitreous cavity, and some o f which approached to internal limiting membrane and lead it to rough and discon tinue; Po7-14 days, the capillary in retina expanded, migrated and broke though t internal limiting membrane which got to the pro retina and became the new ves sels. And typical NVERM were observed. Po28 days, some vascularslike structure formed in vitreous cavity. None of mouse in control group developed NVERM. Conclusion Auto-cortex of crystalline lens can induced neovascular epiretinal membrane in C57BL/6 mouse. (Chin J Ocul Fundus Dis,2008,24:118-121)
Age-related macular degeneration (AMD) is a multifactorial disease affected by environmental factors and genetic variation, which is a major cause of irreversible vision loss in the elderly. miRNA is a kind of endogenous non-coding RNA, which plays an important role in the pathogenesis of AMD, such as oxidative stress, pathological neovascularization and inflammation, by inhibiting or silencing the expression of transcription genes. miRNA has unique advantages in terms of ease synthesis, targeting and additive effect, a large number of experiments have proved the therapeutic potential of miRNA in AMD, which is expected to become a new method for the treatment of AMD in the future. Since the pathogenesis of AMD has not been fully elucidated, it is still necessary to continue to study the pathogenesis of AMD, the biological effects and mechanisms of various miRNA in the occurrence and development of AMD, and observe its therapeutic effects in AMD, so as to provide more effective options for the precise prevention and treatment of AMD.