ObjectiveTo observe the inhibitory effect of endostatin (ES) on oxygen-induced retinal neovascularization.MethodsThirtyfour 7-day-old C57BL/6J mice were randomly divided into 3 groups: oxygen-exposed group (12 mice), ES group (12 mice) and the control group (8 mice). The mice in oxygen-exposed and ES group were exposed to (75±5)％ oxygen for 5 days and then back to the normal air. In ES group, 1 μg ES endostatin were injected into vitreous in one eye, while PBS was injected into the other eye as the control 12 and 36 hours after being exposed to oxygen. The mice in the control group were fed in normal circumstance. The changes of retinal neovascularization was examined by fluorescence angiography with fluorescein isothiocyanatedextran. The number of endothelial cells breaking through the internal limiting membrane (ILM) was counted and the inhibitory effects of ES on retinal neovascularization was observed.ResultsCompared with the oxygen-exposed group, the branches of retinal vessels went normal without any un-perfused area in ES group. The number of nuclei of endothelial cells breaking through ILM on each retinal crosssection decreased to (5.39±1.52), which differed much from that in the oxygen-exposed group (22.56±2.13) (plt;0.001).ConclusionES can effectively inhibit the formation of retinal neovascularization in rats and might be a new path of the treatment for proliferative retinopathy.(Chin J Ocul Fundus Dis, 2005,21:314-317)
Objective To observe the efficacy and safety of intravitreal injection of Ranibizumab(Lucentis) on exudative age－related macular degeneration (AMD). Methods To analyze retrospectively the clinical data of 56 patients with exudative AMD, which was diagnosed by examination of ETDRS charts, color fundus photograph, fluorescein angiography(FFA) or indocyanine green angiography(ICGA) and optical coherence tomography(OCT), were underwent intravitreal injection Lucentis 0.5 mg. Before the treatment, the ETDRS charts letter of 56 eyes was 25.1; choroidal neovascularization(CNA) was leaky which examined by FFA and ICGA; the average thickness of retina was 303.45 mu;m. Ranibizumab injection therapeutic times were 2.8, the average therapeutic times were 3.1. Follow－up time was 6－12 months (mean 8.7 months). Visual acuity (ETDRS charts letter), retinal thickness, leakage of CNV and operative complications before and after the treatment were analyzed. Results At the end of the follow－up period, the mean letter of ETDRS charts was 38.5, increased 13.4 letters (P＜0.01), the ETDRS charts improved 15 or more letters in 22 eyes (39.3%), decreased more than 15 letters in 2 eyes (3.6%); the foveal thickness on OCT images were 303.45 mu;m before treatment and 191.35 mu;m a fter treatment, decreased significantly (P＜0.00); FFA and/ or ICGA showed CNV complete closure in 12 eyes (21.4%), partial closure in 33 eyes (58.9%), no change in 9 eyes (16.1%) and new CNV in 1 eye (1.8%); Slight complications after operation disappeared during one week. Conclusion Intravitreal injection of Ranibizumab for exudative AMD was well tolerated, with an improvement in VA, FFA or ICGA , and OCT. (Chin J Ocul Fundus Dis,2008,24:160-163)
Objective To investigate the manifestations of indocyanine green an giography (ICGA) of the choroidal neovascular membrane (CNV) and the relationship with histopathological changes in patients with age-related macular degeneration (AMD). Methods Twenty-one eyes of 21 patients with AMD diagnosed by ICGA were classified into three types based on ICGA findings: developing type in 9 eyes , degenerating type in 9, and stabilizing type in 3. CNV was extracted by vitrectomy and the histopathological characteristics of CNV was observed under the light and electron microscope. Results The histopathological characteristics of the specimens of developing type revealed abundant CNV partly enwrapped with non-pigmental cells and fibrous tissue or a few pigmental cells; degenerating type revealed reduced activation duration of CNV, many pigmental cells and a little fibrous tissue; stabilizing type revealed a mass of fibrous tissue，few CNV and nonexistence of pigmental cells. Conclusion The histopathological characteristics of exudative AMD may be related to the manifestations of ICGA. (Chin J Ocul Fundus Dis，2004，20：71-74)
Objective To determine the effect of posterior vitreous detachment on the prognosis of branch retinal vein occlusion (BRVO). Methods One hundred and sixteen patients (116 eyes) with BRVO who underwent vitreous examination were retrospectively studied.The relati onship of vitreous conditions to posterior segment neovascularization and macular edema was statistically investigated. Results In 40 ischemic cases,12 of 25 eyes (48.0%) with no posterior vitreous detachme nt (PVD) or partial PVD developed retinal or optic disc neovascularization ,or both,but only one of the 15 eyes (6.7%) with complete PVD developed neovasculariz ation during a mean follow-up period of 10.7plusmn;2.2 months (Plt;0.05) . Diffuse macular edema was found in 45 eyes (38.8%).The incidence o f macular edema was significantly higher in eyes with vitreomacular attachment (51.5%) than in those with vitreomacular separation (22.0%) (Plt;0.01). Conclusion It was suggest ed that compl ete PVD may play a role in protecting eyes with BRVO from posterior segment neov ascularization and macular edema. (Chin J Ocul Fundus Dis, 2001,17:2-4)
ObjectiveTo analyze the regulative rule of mRNA of vascular endothelial growth factor (VEGF) in mice with oxygen-induced retinopathy, and to elucidate the possible mechanism of occurrence of neovascularization in retinopathy of prematurity (ROP).MethodsSixty 7-day-old C57BL/6J mice were divided into oxygen-induced retinopathy group and control group. In oxygen-induced retinopathy group, 36 mice were exposed to 75% oxygen for 5 days and then to room air for 5 days; in control group, 24 mice were raised in room air. Vascular perfusion of fluorescein and retinal stretched preparation were used to observe the morphologic changes of retinal vessels. Reversal transcriptionpolymerase chain reaction (RT-PCR) was used to observe changes of VEGF mRNA in each group. ResultsIn oxygen-induced retinopathy group, the morphologic characteristics of retinal vessels were the unperfused area at the center of superficial and deepseated vessels, and the neovascularization appeared at mid-peripheral retina after 2 days in relative hypoxia condition. The results of RT-PCR showed space-time corresponding relation between expression of VEGF and neovascularization, which meant that the transcription of VEGF mRNA decreased in hyperxia conditionand increased in relative hypoxia condition. ConclusionHypoxia is the main reason of occurrence of retinal neovascularization; increased expression of VEGF caused by relative hypoxia after hyperxia might be effective in reducing the occurrence of neovascularization in ROP.(Chin J Ocul Fundus Dis, 2005,21:292-295)
Objective To evaluate the effects of traspupillary thermotherapy (TTT) for the treatment of central exudative chorioretinopathy (CEC). Methods Twelve eyes of 12 patients who suffered from CEC were treated by using a diode laser at 810 nm. A variable spot size of 0.5mm-2.0mm was used depending on the size of choroidal neovascularization (CNV).The treatment was initiated in one spot for 55 to 60 seconds duration at a power range between 200-350 mW, and the treated area revealed no visible color change to a light-gray appearance. Preoperative and postoperative fluorescein angiography (FFA) and indocyanine green angiography (ICGA) were performed in 10 of the 12 eyes. Results The visual acuity in all eyes was improved to different degree over a period of 3-10 months. Five or more lines improvement measured by Snellen chart in visual acuity was found after the treatment in 4 eyes, three to five lines in 5 eyes and one to two lines in 3 eyes. All eyes demonstrated decreased or vanished exudation in FFA. CNV disappeared or decreaced in 8 eyes and remained nochange in 2 eyes in ICGA. Conclusion TTT is obviously effective in treating CEC. (Chin J Ocul Fundus Dis, 2002, 18: 187-189)
Retinal neovascularization is a complicated pathophysiological process as a result of imbalance between angiogenic and antiangiogenic factors. Correct understanding of the signaling pathways, exploring the critical factors involved in retinal angiogenesis, looking for new strategies by reconstructing the new vessels are helpful for knowing the mechanism of the occurrence and development of reitnal neovascularization, which would be good for preventing and treating retinal neovascularization diseases.