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.
Objective To resolve the tough problem of how to observe the growing cells in an opaque vector. Methods The urethral epithelial cells from a young male New Zealand rabbit were inoculated, and were primarily cultured in vitro and subcultured for 3 passages. Then, the urethralepithelial cells were cultured in the collagen chitosan complex for 3, 7, 14 and 21 days. The cells were dyed with 6-carboxyfluorescein diacetateacetoxymethyl ester and propidium iodine, respectively. Then, Interactive Laser Cytometer was used to detect the growing cells. Results The urethral epithelial cells grew and proliferated very well in the collagen chitosan complex vector. After the urethral epithelial cells grew in the collagen-chitosan complex vector for 3 and 7 days, the fluorescent density amount of the surviving cells were(1.09±0.13)×10.8 and (2.04±0.13)×10.8, respectively. However, after 14and 21 days, the fluorescent density amount of the surviving cells was (0.55± 0.09)×10.8 and (0.47±0.03)×108, respectively. There was a significant difference when compared with the amount of the surviving cells at 3 and 7 days（P＜0.05）.Conclusion Using Interactive Laser Cytometer for measurement of the green and red fluorescent densities of different waves, the activity of the cultured urethral epithelial cells in vitro can be rapidlymeasured with the in situ quantitation method. This method solves a difficult problem of observing the growing cells in an opaque vector. The dynamic growing state of the engineering tissues can be observed.
hrbondioxide laser knife was ued to excise 40 cases of burn crusts and late cicatrices and the resuIts were compored with that from the ordinary surgieal knife. The extent of tiSsue damage,the operative successful rate and the amount of bleeding were obsered in both groupe. It was proved that by using,earbondioxide laser knife to excIse the tissue resulted in very limited damage of tissue,it did not influence the tissue healing and the amount of bleeding was far less than that fro...
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, antiinflammation drugs to antivascular 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.
Objective
To investigate the early effects of intervention with tanakan on retinal function in diabetic retinopathy(DR) after laser photocoagulation.
Methods
Prospective random controlled study was performed on 60 Patients (60 eyes) from 23 to 69 years old with DR(phase Ⅲ～Ⅳ). The multifocal electroretinograms (MERG) were tested with VERIS Ⅳ before, the 3rd day and the 7th day after photocoagulation.
Results
No significant differences were found in the latencies and response densities of N1,P1 and N2 between the two groups before photocoagulation. Compared with that before photocoagulation, three days after photocoagulation the latencies in tanakan group had no significant change. The response densities of N1,P1 and N2 reduced and the changes were much smaller than that in control. Three days after photocoagulation, the response densities of P1 and N2 in the central macula 5°area were much higher and the latencies of P1 and N2 were significantly shorter than that in control group. There were no significant differences in the response densities in the 7th day and the differences in the latencies between two groups still existed.
Conclusion
Tanakan may be effective in preventing the retina from damage of retinal photocoagulation in some degree in DR.
(Chin J Ocul Fundus Dis, 2002, 18: 208-211)
