Objective To observe the histopathological changes in human eyes with ischemic central retinal vein occlusion (CRVO), and to provide objective basis for effective methods of prevention and treatment for (CRVO). Methods Histopathological analysis was performed on the samples of 11 eyes in 11 patients with ischemic CRVO. The changes of central retinal veins (CRV) and central retinal arteries (CRA) wereobserved. Results The lumen of CRV became narrow when passed through the lamina cribrosa in 11 eyes, in which organized thrombus was found in the lamina cribrosa region and post lamina cribrosa region in 5 eyes, and organized thrombus re-unobstructed channels, endothelial proliferation and narrow lumen were found in 6 eyes. Arteriosclerosis of the CRA was observed in all of the 11 eyes with thick wall of the artery and narrow lumen. Proliferation of endothelium of wall of CRA and narrow lumen in the lamina cribrosa region was found in 2 eyes and no thrombus was found at the lamina cribrosa level. Conclusion During the course of ischemic CRVO, thrombus occurs in CRV at the level of lamina cribrosa. The prognosis of CRVO may lie on the time and degree the thrombosis re-opens. The mechanism of CRVO is that CRV is pressed in the narrow interspace of scleral channels of lamina cribrosa. (Chin J Ocul Fundus Dis, 2007, 23: 163-165)
Objective To observe the effect of preservation of an terior lens capsule on the incidence of complications associated with silicone oil. Methods Eighty-two patients(82 eyes)accepted trans pars plana vitrectomy combined with lensectomy,30 eyes with preservation of an terior lens capsule (PAC) and 52 eyes with no preservation of anterior capsule(N PAC)were observed.The incidence of complications was analysed to investigate whe ther PAC could reduce the complications associated with the usage of tamponade of silicone oil. Results The incidence was 50.0% in NP AC group,and 23.3% in PAC group(0.010lt; Plt; 0.025).There were secondary glaucoma(21.1%),band keratopathy(13.5%)and corneal decompensation(9.6%)in NPAC group,while there was none of them in PAC group. Conclusion Preservation of anterior lens capsule is an effective measure to reduce the complicaltons associated with the tamponade of silicone oil. (Chin J Ocul Fundus Dis, 2001,17:41-43)
Objective To investigate the occurrence, progress and conversion of hypotony in anterior proliferative vitreoretinopathy (aPVR), and to provide knowledge about how to prevent and treat it． Methods Animal models of chronic hypotony by aPVR were made with cultured ho mologous dermal fibroblasts on pigmented rabbits．The intraocular pressure (IOP) and ultrasound biomicroscopy(UBM) examination were taken preoperatively and on days 7,14, 28 and 56 postoperatively．Rabbits were killed on days 14, 28 or 56 postoperatively, prepared for histology and ultrastructure examination． Results The average IOP of experimental group was lower than that of control group on days 7,14,28 and 56 significantly (Plt;0．01)．UBM demonstrated that trip like echo emerged in front of ciliary body four weeks postoperatively, and tractional retinal detachment was found four weeks and eight weeks postoperatively in experimental group． Microscopic examination showed atrophy orabsence of the non-pigmented ciliary epithelium on days 28 and 56 postoperatively in experimental group．Electronic microscopy showed that the amount of mitochondrions decreased and there were many vacuoles in the non-pigmented ciliary epithelium in experimental group four and eight weeks postoperatively． Conclusions Atrophic change of the non-pigmented epithelium due to dragging effect of the ciliary body from the epiciliary membrane in aPVR might be the main cause of hypotony． (Chin J Ocul Fundus Dis, 2001,17:216-220)