PURPOSE:To observe the effect of laser/photocoagulation on prevention of recurrence of retinal datachment following removal of intraocular silicone oil. METHODS:Laser photocoagulation was performed in a series of 24 cases (24 eyes)which had been formerly operated on with vitreoretinal surgery and intraocular silicone oil tamponade for retinal datachment,2 weeks to 3 months before intraocular silicone oil removal. Argon green or krypton red laser photocoagulation were done in whole or half cycle scattered laser burns behind the sclera! ridge. RESULT:Among the 24 eyes ,after the intraocular silicone oil had been removed, 22 (91.7%)eyes had their retinas retained in normal position. CONCLUSION :Laser photocoagulation before removal of intraocular silicone oil might be helpful in avoiding the recurrence of retinal detachment. （Chin J Ocul Fundus Dis,1997,13: 197-198）
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.
Objective To investigate the therapeutic effects of retinal angioma. Methods The clinical data of 16 cases(20 e yes) were retrospectively analyzed, and the patients included 5 males and 11 females of 23.3 yeras old on average. Four cases in this series affected by bilateral retinal angiomas were identified as von Hippel-Lindou disease. The retinal an giomas were divided into 5 stages according to their degrees of developmnet from simple angiom without vessel dilation to feeder vessel dilation and intraretina l exudates, local retinal detachemnt, massive retinal detachment and complication occurrence in proper order. The methods of treatment were laser photocoagulati on, trans-scleral cryotherapy and vitreoretinal surgery. The patinets were followed up for 37.8 months on average. Results There were 10 eyes (2 in stage 1, 7 in stage 2, 1 in stage 3)treated with laser photocoagulation, and all of the angiomas were controlled after the treatment. The visual acuity im proved in 2 eyes, decreased in 4 eyes, and remained unchanged in 4 eyes. Cryothe r apy was performed on 7 eyes(5 in stage 3, 2 in stage 4). The visual deteriortion was found in 5 eyes; and the state of illness was stable in 3 eyes in stage 3 a nd aggravating in 4 eyes (2 in stage 3, 2 in stage 4). Vitreoretinal surgery was performed on 4 eyes including 2 which had been given photocoagulation, and the visual acuity improved in 2 eyes, decreased in 1 eye, and was unimproved in 1 ey e . The visual acuity decreased to no light perception in an untreated eye after 1.5 year follow-up. New angiomas occurred in 3 eyes with Von Hippel-Lindou disease in the follow-up period. Conclusion Laser photocoagulation is effective in treating the angiomas from stage 1 to 3. Cryotherapy can cause massive exudation and proliferation, and it is only suitable for a few patients in stage 3. The visual prognosis is more favorable in vitreoretinal surgery tha n other therapies for the patients in stage 4. (Chin J Ocul Fundus Dis, 2001,17:296-298)
PURPOSE:To investigate the effect of the retinal ganglion cell on the origin of the scotopic threshold response(STR)of the cat and human electroretinogram. METHODS:An optic atrophy model was established in cats with retinal photocoagulation around the optic disc. The STR and flash visual evoked potentials(FVEP)were recorded from 18 cases(24 eyes)of normal human,6 cases of the optic atrophy patients,6 cases of normal cats and 4 cases of retinal photocoagulating cats in 4, 8 and 16 weeks after retinal photocoagulation. In addition,ganglion cells were observated in 8 and 16 weeks after retinal photocoagulation using light and electron microscopes. RESULTS :The pathologic changes after retinal photocoagulation verify secondary atrophy of ganglion cells. STR was normal and FVEP was not recorded in cats of retinal photocoagulation and patients with optic atrophy. CONCLUSION :Retinal ganglion cell loss does not abolish the cat and human STR.There is no effect of ganglion cell on the origin of STR. （Chin J Ocul Fundus Dis,1997,13: 215-218 ）