ABSTRACT
Objective:Glaucoma is a multifactorial optic neuropathy with a high rate of irreversible visual loss,and its pathogenesis is complex and still unclear.Elevated intraocular pressure(IOP)is well recognized as the sole modifiable risk factor for the development of glaucoma in the majority of cases.This study aims to compare 2 different methods of inducing chronic ocular hypertension by circumlimbal suture or by laser burns in degree and lasting time of the IOP,different status of the retina and retinal ganglion cells(RGCs),and changes of the microstructure of neurons. Methods:The chronic ocular hypertension models were induced by 2 different ways.One kind of the models was built by unilateral circumlimbal suture(10/0)implantation(suture group),another kind of model was built by laser burns at trabecular meshwork and episcleral veins(laser group).The untreated contralateral eye served as the control group.Changes in IOP were observed and regularly monitored in the 2 groups of rats.HE staining was applied to observe the retinal and optic nerve pathology.Transmission electron microscope(TEM)was used to observe the mitochondrial morphology.RGCs were specifically labeled with Brn3b antibody and counted.The expression of caspase-3 was detected by Western blotting to clarify the apoptosis of RGCs. Results:Compared with the control group,IOP were significantly increased in the suture group and the laser group(both P<0.05).The suture group induced a 1.5-fold elevation of IOP,and sustained for 8 weeks.The laser group induced a 2-fold elevation of IOP for 12 weeks.Both methods could cause RGCs loss(both P<0.05),which were verified by pathology and immune staining of Brn3b.The expressions of caspase-3 were also increased(both P<0.05).The mitochondrial morphology became more fragment,which changed from long shape to round and small one under TEM in 2 models.For comparison,the pathology changes of retinal structure in suture group were not obviously than those in the laser group. Conclusion:Circumlimbal suture can build an effective model of chronic elevated IOP and induce glaucomatous pathologic changes similar to those in the laser photocoagulation,but the pathologic changes are milder than those in laser photocoagulation.Compare with translimbal laser photocoagulation,equipment and skill demand for circumlimbal suture is less.
ABSTRACT
OBJECTIVES@#Age-related macular degeneration (AMD) is one of the 3 major eye diseases recognized by WHO to prevent blindness, and which is the main cause of irreversible visual impairment in the elderly. This study aims to analyze the disease epidemiological burden, and provide a theoretical foundation for the prevention and control of AMD in China based on the data in global burden of disease (GBD) 2019.@*METHODS@#The prevalent cases/prevalence, disability-adjusted life year (DALYs)/DALY rate of AMD and socio-demographic index (SDI) for global and China were searched from the GBD 2019 database to analyze the epidemiological trend, age-period-gender trend of AMD in China from 1990 to 2019, and to evaluate the relations between the prevalence and SDI.@*RESULTS@#In 2019, the prevalence of AMD in China was at a high level in the world, and the number of prevalent cases were 1.93 times of that in 1990. The prevalence and DALY rates continued to rise. The age trend of AMD in China was high at the middle of the age stages and low at the two ends, and which was higher in the female than in the male. With the increase of SDI, the prevalence of AMD was increased linearly.@*CONCLUSIONS@#The disease burden of AMD in China is increased significantly and is positively correlated with the social development from 1990 to 2019. It is of great significance to study the relationship between epidemilolgical data of AMD and social development level for diagnosis treatment and policy of AMD.