Objective To observe the inhibiting effects of alginate sodiumretinoic acid（AGS-RA）microspheres release system on the laser coagulationinduced subretinal proliferation.Methods RA were dissolved by absolute alcohol,then mixed with 1.5% AGS and made into AGSRA microspheres by a microcapsule electrostatic generator. The parameter of laser injury include irradiation time (0.20 s)，spot diameter (200 mu;ｍ) and output power (420 ｍＷ).Thirty pigmented rabbits were randomly divided into 3 groups (laser injury，experimental and control group).After laser coagulation,AGSRA or blank microspheres were immediately injected into the vitrous of experimental and control rabbits respectively.The height,width and area of 6 retinal spots of laser coagulation at each timepoint were analyzed histopathologically with serial retinal sections at 1,2,3,4,and 6 weeks after laser coagulation.Results Histopathological examination showed that there were morphological and distribution changes of retinal cells in all layers, and localized fibroblasts proliferation in the retina after laser injury. The laserinduced responses in experimental group were much milder（P＜0.01）, while the laser injury group and control group have same width（P＞0.05）and height/area of laser spots（P＞0.05）.Conclusion AGSRA release system can alleviate the subretinal proliferate after laser injury.
Corticosteroids, anti-vascular endothelial growth factor, antibiotics and antiviral were the main 4 classes of drugs for intravitreal injection. Depending on the class and volume of medication, age and gender of patients, ocular axial lengths or vitreous humour reflux, intraocular pressure (IOP) can be elevated transiently or persistently after intravitreal injection. Transient IOP elevation occurred in 2 weeks after intravitreal injection, and can be reduced to normal level for most patients. Only a small portion of such patients have very high IOP and need intervention measures such as anterior chamber puncture or lowering intraocular pressure by drugs. Long term IOP elevation is refers to persistent IOP increase after 2 weeks after intravitreal injection, and cause optic nerve irreversible damage and decline in the visual function of patients. Thus drug or surgical intervention need to be considered for those patients with high and long period of elevated IOP. Large-scale multicenter clinical trials need to be performed to evaluate the roles of the drug and patients factors for IOP of post-intravitreal injection, and to determine if it is necessary and how to use methods reducing IOP before intravitreal injection.