Objective：To observe the protective effect of ginkgo bilo ba extrac t (EGb 761), a free radical scavenger, on the photoreceptor cells after lighti nduced retinal damage. Methods：Seventytwo female SpragueDa wley (SD) rats we re randomly divided into 4 groups: normal control group, lightinduced retinal da m age model group, model+physiological saline group, and model+EGb 761 group, with 18 rats in each group. All of the rats except the ones in the control group were exposed to white light at (2740plusmn;120) lx for 6 hours after the dark adap tation for 24 hours to set up the lightinduced retinal damage model. Rats in m o del + physiological saline group and model+EGb 761 group were intraperitoneall y injected daily with physiological saline and 0.35% EGb 761 (100 mg/kg), respec tively 7 days before and 14 days after the light exposure. Apoptosis of photorec eptor cells was detected 4 days after light exposure; 7 and 14 days after light exposure, histopathological examination was performed and the layer number of ou ter nuclear layers (ONL) on the superior and inferior retina was counted. Results：Four days after light exposure, the apoptosis of photorecep tor cells was fou nd on ONL in model, model+ physiological saline and model+EGb 761 group, and w as obviously less in model + EGb 761 group than in model and model+physiologic al saline group. Seven days after light exposure, the layers of ONL on the super ior retina were 3 to 4 in model and model+physiological saline group, and 7 to 8 in model+EGb 761 group; the mean of the layer number of ONL in model+EGb 761 group (6.92plusmn;0.82) was less than that in normal control group (8.40plusmn;0.95) (t=-1.416, P＜0.05), but significantly more than that in model (5.96 plusmn;1.36 ) and model+physiological saline group (5.90plusmn;1.40）（t=1.024, 1.084; P＜0.05). Fourteen days after light exposure, the layers of ONL on the superior retina were 0 to 1 in model and model+physiological saline group, and 3 to 4 i n model+EGb 761 group. The mean of the layer number of ONL in model+EGb 761 group (5.5 2plusmn;1.06) was significantly more than that in model (3.44plusmn;2.15) and model + physiological saline group (3.37plusmn;1.91) (t=2.082, 2.146, P＜0.05). Conclusion：EGb 761 can partially inhibit the apoptosis of pho toreceptor cells, thus exert protective effect on photoreceptor cells.
ObjectiveTo investigate the medium and long-term influence of silicon oil versus heavy silicone oil on rabbit retinas. Methods28 health standard rabbits were randomly divided into A, B and C groups, with 12, 12 and 4 rabbits respectively. All rabbits received routine vitrectomy and tamponade with silicone oil (group A), or heavy silicone oil (group B) or balanced salt solution (group C). After 4, 8, 12 and 24 weeks, the retinal b-wave amplitude was measured by ERG, posterior retinal thickness was measured by optical coherence tomography (OCT). Retinal ultrastructure and tissue morphology were observed by transmission electron microscopy and optical microscopy. ResultsCompare to group C, the b-wave amplitude decreased at 4 weeks after surgery, and decreased at 8 weeks after surgery for group B, and decreased at 8 weeks after surgery, and decreased at 24 weeks after surgery for group A. The decreases were greater in group B than group A at 8, 12, 24 weeks after surgery, the difference was statistically significant (P < 0.05). The posterior retinal thickness of group A and B was thinner than group C at 24 weeks after surgery (P < 0.05). The decreases were greater in group B than group A, the difference was statistically significant (P < 0.05). Transmission electron microscopy and optical microscopy revealed severe pathological changes of retinal ultrastructure and morphology in group A and B rabbit eyes, at 12 weeks and 8 weeks after surgery respectively. The changes were more severe in group B and group A, including edema and necrosis in cone/rod cells, in disk membranes, mitochondria, cytoplasm, nucleus and other organelles. The morphological changes were also more severe in group B and group A, including degenerations of ganglion cell layer, inner nuclear layer changes. Those changes became more severe when the tamponade time extended. ConclusionThe heavy silicone influence on visual function, ultrastructures, histomorphology of rabbit retinas is much worse than the silicon oil, and the effect is more significant with its time prolong.
Objective To observe the expression of related proteins of retina after subretinal implantation with inactive chips.Methods A total of 27 healthy adult New Zealand white rabbits were randomly divided into three groups: operation group (12 rabbits) in which the rabbits were implanted with inactive chips into the interspace beneath retina;shamoperation group (12 rabbits) in which the rabbits were implanted with inactive chips into the interspace beneath retina which was taken out immediately;the control group (3 rabbits). Animals were sacrified for immunohistological study 7,15,30 and 60 days after surgery.The rabbits in control group group were sacrified for immunohistological study after bred for 30 days.The expressions of glial fibrillary acidic protein (GFAP) and brain derived neurotrophic facor (BDNF) were observed.Results In operation group, the outer nulear layer of retina thinned, and the cells in the inner nulear layer was disorganized 7,15,and 30 days after the surgery;glial cells proliferated 60 days after surgery; the positive expression of BDNF and GFAP was more than that in the shamoperation and control group.In shamoperation group, the positive expression of BDNF and GFAP was more than that in the control group.No obvious difference of expression of BDNF and GFAP between each time point groups was found.Conclusions The expression of neroprotective related proteins increased after subretinal implantation with inactive chips suggests that limited neuroprotective effects might be led by the implantation.
ObjectiveTo observe the effects of repeated intravitreal injections of anti-vascular endothelial growth factor (VEGF) drugs on vitreous macular interface (VMI) in patients with exudative age-related macular degeneration (AMD).MethodsRetrospective study. Thirty-four exudative AMD patients who treated with intravitreal anti-VEGF drugs were included in this study. There were 26 males and 8 females. The age ranged from 50 to 80 years, with the average of (62.8±8.35) years. The eyes with at least 6 treatments during the 1-year follow-up were taken as the study eyes, and the eyes with no anti-VEGF drug treatment were the control eyes. Optical coherence tomography (OCT) examination was used to observe the VMI status of both eyes before treatment. Vitreous macular adhesion (VMA), macular epiretinal membrane (MEM), and complete vitreous detachment (C-PVD) were defined as abnormalities in VMI. The VMA was classified as focal (≤1500 μm) and broad (＞1500 μm) depending on the diameter of the vitreous and macular adhesions on the OCT images. Before treatment, there were 12 eyes with abnormal VMI in study eyes, including 8 eyes with broad VMA, 3 eyes with focal VMA, and 1 eye with MEM; 12 eyes with abnormal VMI in control eyes: broad VMA in 7 eyes, focal VMA in 2 eyes, C-PVD in 2 eyes, and MEM in 1 eye. The average follow-up time after treatment was 16.4 months. During the follow-up period, OCT was performed monthly in a follow-up mode. Comparing the changes on VMI between before and after treatment in both eyes of patients, respectively. The chi-square test was used to compare the difference on VMI. Because the number of samples was ＜40, Fisher's exact test was used for the analysis.ResultsAt the final follow-up, 12 eyes with abnormal VMI in the study eyes, including 5 eyes with broad VMA, 2 eyes with focal VMA, 3 eyes with C-PVD, and 2 eyes with MEM. There were 6 eyes altered comparing with baseline. In the control eyes, there were 13 eyes with abnormal VMI, including 5 eyes with broad VMA, 7 eyes with C-PVD, and 1 eye with MEM. A total of 6 eyes changed on VMI comparing with baseline. At the final follow-up, there was no significant difference on VMI changes between the study eyes and its corresponding control eyes (P=0.053). In all eyes, a total of 4 eyes changed from focal VMA to C-PVD at the final follow-up, accounting for 80.0% of the total focal VMA; 3 eyes changed from broad VMA to C-PVD, accounting for 21.4% of the total broad VMA.ConclusionsRepeated anti-VEGF treatment has little effect on VMI. Regardless of anti-VEGF therapy, eyes with focal VMA appears to be more prone to C-PVD than the broad one.
Objective To investigate the time and the mechanism of the toxic and side effects of silicone oil on ocular tissues. Methods 19 human eyeballs were examined histopathologically at different time intervals after silicone oil tamponade. Results Microscopic bubbles presumably containing silicone oil were found in sensory retina,RPE,optic nerve, pre and subretinal membrane,iris,anterior chamber angle,and retrocorneal membrane.In the eyes containing silicone oil for less than 9 months.Silicone bubbles were present only in the surface of retina(within preretinal membrane or macrophages),and after that time,silicone bubbles were noted within sensory retina.In an eye enucleated 39 months after intravitreal silicone tamponade,the parenchyma and subarachnoid space of the optic nerve were found to be diffusely invaded by silicone bubbles. Conclusion The histopathologic changes of ocular tissues are related to the duration of intravitreal silicone oil tamponade. (Chin J Ocul Fundus Dis, 1999, 15: 232-234)
Objective To observe the expression of vascular endothelial growth factor A (VEGFA) and its receptors sFlt-1, kinase insert domain receptor (KDR) in lightinjured human retinal pigment epithelial (RPE) cells. Methods Cultured human RPE cells (8th - 12th generations) were divided into normal control group and light damage group. The cells of two groups were exposed to the 18 W cold white light (2200±300) Lux for 12 hours to induce light damage responses, but the cells of normal control group were packed by tinfoil with doubledeck high pressure disinfection. The VEGF-A, sFlt-1 and KDR mRNA and protein expressions were detected by reverse transcriptionpolymerase chain reaction (RT-PCR) and Western blot at 0, 6, 12, 24 hours after light damage. Results The VEGF-A mRNA and protein expressions in light damage group were significantly increased at 6 hours, and reached its peak at 12 hours after light damage which obviously higher than that in normal group (t=2.74, 2.93; P＜0.05), and then went down gradually. The sFlt-1 mRNA and protein expressions in light damage group reached its peak at 12 hours after light damage which obviously higher than that in normal group (t=4.32, P＜0.01), but obviously lower than that in normal group at 24 hours after light damage (t=2.41, P＜0.05). The KDR mRNA and protein expressions in light damage group were obviously higher than that in normal group at 24 hours after light damage （t=2.89, P＜0.05）,but there was no changes at 6, 12 hours after light damage (t=1.84, P＞0.05). Conclusions At 6, 12 hours after light damage, the expressions of VEGF-A and sFlt-1 increases significantly and KDR expression is stable in lightinjured RPE cells. At 24 hours after light damage, the expression of VEGF-A and sFlt-1 decreases, but KDR expression increases in light-injured RPE cells.
ObjectiveTo observe the changes in physical properties of silicone oil after intraocular tamponade. MethodsThe silicone oil was removed from 99 patients (99 eyes) of primary retinal detachment with 23G vitreous cutter system. The upper silicone oil was collected after put the vitrectomy samples at room temperature for 3 days. According to the time of intraocular tamponade, the silicone oil samples were divide into six groups including group A (1 month, 12 samples), group B (2 months, 15 samples), group C (3 months, 25 samples), group D (6 months, 22 samples), group E (1-2 years, 13 samples) and group F (above 2 years, 12 sample). Fresh unused silicone oil was set as blank control group. Then the emulsion particles, kinematic viscosity, surface tension, density, transmittance and refractive index were measured. ResultsThe difference between group A-F and the control was statistical significant (P<0.05) in emulsion particles (F=89.337), kinematic viscosity (F=10.660), surface tension (F=11.810), density (F=13.497), transmittance of wavelengths (F=455.496, 566.105, 525.102, 767.573, 622.961, 601.539), but not statistical significant at refractive index (F=2.936, P>0.05). The number of silicone oil emulsion particles has no statistical difference between group A and the control (P>0.05), but was significantly different between group B-F (P<0.05). The kinematic viscosity of silicone oil has no statistical difference between group A, B and the control (P>0.05), but was significantly different between group C-F (P<0.05). The surface tension of silicone oil has no statistical difference between group A-D and the control (P>0.05), but is significantly different between group E and F (P<0.05). The density of silicone oil has no statistical difference between group A-D and the control (P>0.05), but was significantly different between group E and F (P<0.05). The transmittance of silicone oil has statistical difference between group A-F and the control(P<0.05). The refractive index of silicone oil has no statistical difference between all the groups and the controls significantly (P>0.05). ConclusionsThe physical properties of silicone oil will change during the intraocular tamponade. The emulsion particles number will increase and the transmittance will decrease after 2 months, the kinematic viscosity of silicone oil will decrease significantly after 3 months, and the density and surface tension will change significantly after 1 year of tamponade.
Objective To investigate the refractive changes of ocular measurable factors due to scleral buckling surgery. Methods A total of 86 eyes of successful rhegmatogenous retinal detachment with a higher encircling scleral buckle underwent A-scan and keratometer examination before surgery as well as l week,4 and 12 weeks after surgery.The refractive factors included the depth of anterior chamber,thickness of lens,axial length of eye,corneal curvature and refraction of eye were detected pre- and post-operatively. Results Compared with preoperation,the depth of anterior chamber was decreased significantly at the lst,4th and 12th postoperative week(P＜0.05),while no significant change of the axial length of eye was observed.The thickness of lens was increased significantly and the refractive error was myopic shifted at the lst and 4th week after operation(P＜0.05),but no significant change was observed at the 12th postoperative week.Statistically significant difference was also observed in corneal curvature of central axis in the local bucklele;1 quadrant with encircling group between preoperation and the lst and 4th postoperative week. Conclusions With higher encircling scleral buckle,the refractive change after buckling surgery may be caused primarily by the shallowing of anterior chamber and thickening of lens. (Chin J Ocul Fundus Dis, 1999, 15: 227-229)
Objective To observe the visual field loss after 577 nm krypton pan-retinal photocoagulation (PRP) in the treatment of diabetic retinopathy (DR). Methods A prospective clinical studies. Forty-six eyes of 26 patients with proliferative DR (PDR) and severe non-proliferative DR (NPDR) diagnosed by clinical examination from No. 306 Hospital of PLA during January 2014 and December 2015 were included in this study. Among them, 21 eyes of NPDR and 20 eyes of PDR; 13 eyes with diabetic macular edema (DME) (DME group) and 28 eyes without DME (non-DME group). All eyes underwent best corrected visual acuity (BCVA), fundus color photography, fundus fluorescein angiography (FFA) and optical coherence tomography (SD-OCT) examinations. The visual field index (VFI) and visual field mean defect (MD) values were recorded by Humphrey-7401 automatic visual field examination (center 30° visual field). The BCVA of DR eyes was 0.81±0.28; the VFI and MD values were (89.8±8.4)% and −7.5±3.85 dB, respectively. The BCVA of the eyes in the without DME group and DME group were 0.92±0.20 and 0.57±0.27, the VFI were (90.86±7.86)% and (87.46±9.41)%, the MD values were −6.86±3.43 and 8.87±4.48 dB. PRP was performed on eyes using 577 nm krypton laser. The changes of VFI, MD and BCVA were observed at 1, 3, and 6 months after treatment. Results Compared with before treatment, the VFI of DR eyes decreased by 12.0%, 12.3% and 14.8% (t=7.423, 4.549, 4.79; P＜0.001); the MD values were increased by −4.55, −4.75, 6.07 dB (t=−8.221, −5.313, −5.383; P＜0.001) at 1, 3 and 6 months after treatment, the differences were statistically significant. There was no difference on VFI (t=1.090, −0.486; P＞0.05) and MD value (t=−0.560, −0.337; P＞0.05) at different time points after treatment. Compared with before treatment, the BCVA was significantly decreased in DR eyes at 1 month after treatment, the difference was statistically significant (t=2.871, P＜0.05). Before and after treatment, the BCVA of the DME group was lower than that of the non-DME group, the difference were statistically significant (t=4.560, 2.848, 3.608, 5.694; P＜0.001); but there was no differences on the VFI (t=1.209, 0.449, 0.922, 0.271; P＞0.05) and MD values (t=1.582, 0.776, 0.927, 1.098; P＞0.05) between the two groups. Conclusion The range of 30° visual field loss is about 12%-14.8% after 577 nm krypton laser PRP for DR. VFI and MD can quantitatively analyze the and extent of visual field loss after PRP treatment.
Objective To observe the clinical manifestations, therapeutic efficacy and results of bacterial culture of seven patients of scleral buckle (SB) infection after scleral bulking surgery. Methods Seven patients (seven eyes) underwent SB removal for SB infections were enrolled in this study. The patients included four males (four eyes) and three females (three eyes). The patients aged from 12 to 69 years, with a mean age of 42.7 years. There were four right eyes and three left eyes. The duration (interval between primary surgery and SB removal) ranged from two weeks to ten years, with a mean of 47.5 months. Six patients were concurrent with systemic disease. All the patients were examined for visual acuity, slit lamp microscope and indirect ophthalmoscope examination. Some patients also received external eye examination and fundus photography. Whether SB exposure or not and the clinical manifestations were observed. SB removal was performed in all the patients and the SB were sent to the laboratory for bacterial culture. The follow-up time ranged from two weeks to eight months, with a mean of 3.2 months. Whether infections recurrence and retinal detachment or not were observed. Results SB exposure was in three eyes. Obvious ocular pain and swelling, conjunctival hyperemia and visible yellow-white discharge in the conjunctival sac were presented in two eyes; irritation and discharge were in one eye. No SB exposure was in four eyes. Ocular pain and swelling, conjunctival hyperemia and visible yellow-white discharge in the conjunctival sac were presented in two eyes. Repeated subconjunctival hemorrhage and diplopia were presented in one eye. Visual acuity decline, conjunctival sac discharge and total retinal detachment were in one eye. All patients had no intraocular inflammation. The infection was controlled after SB removal and the retina was attached during the follow-up. The bacterial culture were all positive, which included Staphylococcus aureus, Staphylcoccus epidermidis and Erysipelothrix rhusiopathiae, Gram positive corynebacterium, Aspergillus flavus, Kocuria roseus, Streptococcus oralis, Maxwell Corynebacterium. Conclusions The clinical manifestations of SB infection and the pathogenic microorganisms are variable. SB removal can control the infection.