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.
ObjectiveTo investigate the potential effect of hyperopia status on subfoveal choroidal thickness (SFCT) in silicone oil (SO)-filled eyes.MethodsThis self-comparative study was conducted in Department of Ophthalmology, Central Theater Command General Hospital. The 50 patients (100 eyes) were collected with unilateral macula-on rhegmatogenous retinal detachment from January 2019 to July 2019, who successfully underwent pars plana vitrectomy (PPV) and SO tamponade. Retinal reattachment was observed after surgery in all patients. One month after PPV, the affected eye was wore soft, contact lenses for 24 hours to correct refractive error (RE), depending on its optometry value. The SFCT of the affected eyes was measured using OCT before and after lenses wear. The fellow eyes also received OCT examination at the same time. T test was used to compare SFCT between SO-filled eyes and fellow eyes.ResultsThe mean RE of the SO-filled eyes was +6.38±1.12 D. The mean SFCT of SO-filled eyes (247.12±17.63 μm) was significantly thinner than that of the fellow eyes (276.32.55±17.63 μm) (P＜0.001). The SFCT of the SO-filled eyes was significantly thinner than fellow eyes, and the difference was statistically significant (t=－3.95, P＜0.001). After lenses wear, the mean SFCT of the SO-filled eyes increased to 276.32±24.86 μm. Compared with before lenses wear, the difference was statistically significant (t=－4.30, P＜0.001). Compared with the fellow eye, the difference was not statistically significant (t=0.05, P＞0.05).ConclusionSFCT reduction in the SO-filled eyes may be due to the hyperopia status caused by SO, which can be reserved by RE correction.
Objective To observe the therapeutic effect of combined surgery of anterior and posterior segment and silicon oil tamponade on macular hole retinal detachment in eyes with high myopia.Methods The clinical data of 48 high myopia patients (48 eyes) with macular hole retinal detachment were retrospectively analyzed. Retinal detachment was mainly at the posterior pole; macular hole was confirmed by noncontact Hruby lens and optical coherence tomography (OCT). Phacoemulsification combined with pars plana vitrectomy and silicon oil tamponade were performed to all patients, of which 41 had undergone internal limiting membrane peeling, and 23 had intraocular lens implanting. The oil had been removed 3.5-48.0 months after the first surgery and OCT had been performed before the removal. The followup period after the removal of the silicon oil was more than 1 year.Results The edge of the macular hole could not be seen under the noncontact Hruby lens 1 week after the surgery in all but 5 patients, and the visual acuity improved. The silicon oil had been removed in all of the 48 patients; the OCT scan before the removal showed that the closed macular holes can be in U shape (8 eyes), V shape (6 eyes) or W shape (23 eyes). About 1338 months after the oil removal, retinal detachment recurred in 2 patients with the Wshaped holes. At the end of the followup period, 16 patients (33.3%) had U or Vshaped macular holes, and 32 patients (66.7%) had Wshaped macular holes. The rate of retinal reattachment was 100%.Conclusion Combined surgery of anterior and posterior segment and silicon oil tamponade is effective on macular hole retinal detachment in eyes with high myopia.
Objective To evaluate glaucoma and anterior chamber angle changes after intravitreal silicone oil injection(SOI). Methods The intraocular pressure(IOP) and anterior chamber angles of 34 e yes(33 patients)undergone pars plana vitrectomy and SOI were observed. Results Glaucoma occurred in 9 eyes(26%),in which silicone oil glaucoma(SOG) accounted for 77%(7/9).The changes of the superior part of anterior chamber angle were peripheral anterior synechiae in 11 eye(32%) and SO emulsification droplets in 22 eyes(64%) in 1～4.5 months after surgeries.Glaucoma occurred in 6 eyes of 7 eyes undergone peripheral iridectomy at the inferio r part of the iris after the closure of iridectomy holes (plt;0.05). Conclusion High incidence of glaucoma was found in this series of patients after intravitreal silicone oil injection,and the main causes of SOG were closure of the inferior iridecomy hole and silicone emulsification. (Chin J Ocul Fundus Dis, 2001,17:105-107)
Silicone oil is widely used in intraocular filling of fundus disease after vitrectomy, which improves retinal reattachment rate andpostoperative visual function of patients. With the era of minimally invasive vitreous surgery coming, the utilization rate of silicone oil filling is decreasing, however, it still plays an indispensable role in the surgical treatment of complex fundus diseases. In the process of using silicone oil, the indications should be strictly selected, and the potential risks should be fully considered and possibly avoided. The study of vitreous substitutes with certain physiological functions is currently a research hotspot in the field of fundus diseases.
ObjectiveTo evaluate the incidence of retinal re-detachment and possible risk factors after removal of silicone oil. MethodsThe clinical data of 821 patients (858 eyes) who underwent removal of silicone oil in General Hospital of PLA during 2008-2012 were retrospectively analyzed. The patients included 518 males and 303 females. The age was ranged from 1 to 79 years old, with an average of 44.03 years. All patients underwent removal of silicone oil after vitrectomy combined with silicone oil tamponade (the tamponade period was ranged from 40 days to 13 years, with an average of 6.82 months). The incidence, time and causes of retinal re-detachment were analyzed. ResultsRetinal re-detachment occurred in 43 patients (44 eyes, 5.13%). Among these retinal re-detachment in 44 eyes, 23 eyes (52.27%) occurred in 1 week, 13 eyes (29.55%) in 1-4 weeks, 4 eyes (9.08%) in 4-8 weeks, 2 eyes (4.55%) in 8-12 weeks, and 2 eyes (4.55%) more than 12 weeks after silicone oil removal. Possible reasons of retinal re-detachment included activated original retinal holes (7 eyes), residual peripheral vitreous (3 eyes), traction of epiretinal proliferative membrane (18 eyes), new retinal hole (9 eyes), non-closure of original retinal holes (5 eyes) and traction of retinal incarceration in the scleral incision (2 eyes). ConclusionsThe incidence of retinal re-detachment after silicone oil removal is 5.13%. The incidence reduced gradually with the extension of time after removal silicone oil.
ObjectiveTo compare the clinical characteristics and analyze the factors affecting vision prognosis of idiopathic macular hole (IMH) or myopic macular hole (MMH). MethodsA cross-sectional study. From October 2012 to October 2020, 336 patients with 346 eyes of IMH and MMH who were diagnosed in Shanxi Provincial Eye Hospital with continuous follow-up data after surgery were included. There were 346 eyes (336 cases), including IMH with 247 cases (255 eyes) and MMH with 89 cases (91 eyes), which were divided into IMH group and MMH group. Best corrected visual acuity (BCVA) and optical coherence tomography were performed in all eyes. The BCVA examination used the standard logarithmic visual acuity chart, which was converted into logarithmic minimum angle of resolution (logMAR) visual acuity. The age of outset in IMH and MMH was 64.8±6.6 and 59.2±8.1 years, the logMAR BCVA was 1.11±0.50 and 1.80±0.78, respectively. There were significant differences in age (Wald=34.507) and logMAR BCVA (Z=－7.703) between two groups (P＜0.05). All eyes were performed inner limiting membrane (ILM) peeling or partial inverted ILM covering hole operation. After the operation, the vitreous cavity was filled with air, C3F8 and silicone oil, including 73, 102, 83 eyes in IMH group and 9, 10, 72 eyes in MMH group, respectively. Follow-up time after surgery was more than 2 months. The optimal BCVA and macular hole closure of the two groups were observed. If the quantitative data conformed to the normal distribution, the generalized estimating equation was used, otherwise, the Mann-Whitney U test or Kruskal-wallis test was used, the χ2 test was used for the comparison of categorical variables. Generalized estimating equation logistic regression analyzed the influencing factors of optimal BCVA after surgery and visual acuity success. ResultsIn IMH and MMH, the optimal logMAR BCVA were 0.71±0.36, 1.10±0.51 respectively, and 147 (57.6%, 147/255) eyes, 63 (69.2%, 63/91) eyes achieved visual success respectively. There was a significant difference in the optimal logMAR BCVA (Z=－6.803, P＜0.005), but no difference in visual success rate (χ2=3.772) between the two groups. The visual success rate of IMH at the same baseline BCVA level was higher than that of MMH, and the difference was statistically significant (χ2=14.500, P=0.001). Logistic regression analysis showed that the influencing factors predicting poor optimal visual acuity after surgery were: IMH, baseline BCVA [odds ratio (OR)=2.941, 95% confidence interval (CI) 1.341-6.447, P＜0.05], MH diameter (OR=1.003, 95%CI 1.001-1.005, P＜0.05), silicon oil filling (OR=3.481, 95%CI 1.594-7.605, P＜0.05); MMH, baseline BCVA (OR=2.549, 95%CI 1.344-4.834, P＜0.05), C3F8 filling (OR=18.131, 95%CI 1.505-218.365, P＜0.05) and silicon oil filling (OR=7.796, 95%CI 0.997-60.944, P＜0.05). The factors leading to a lower likelihood of achieving visual success: IMH, baseline BCVA (OR=213.329, 95%CI 46.123-986.694, P＜0.05), MH diameter (OR=0.995, 95%CI 0.992-0.997, P＜0.05), silicon oil filling (OR=0.326, 95%CI 0.115-0.926, P＜0.05) and duration (OR=1.036, 95%CI 1.005-1.067, P＜0.05); MMH, baseline BCVA (OR=13.316, 95%CI 2.513-70.565, P＜0.05) and duration (OR=1.022, 95%CI 1.001-1.044, P＜0.05). ConclusionsMMH was earlier than IMH in age of outset. Baseline vision significantly affected vision prognosis in IMH and MMH. Silicone oil should be avoided as much as possible under the premise of hole closure.
ObjectiveTo observe the effect and complications of vitrectomy combined with intraocular silicon oil or C3F8 filling for proliferative diabetic retinopathy (PDR). MethodsEighty-six consecutive patients (101 eyes) with PDR-related vitreous hemorrhage who underwent primary standard three-port vitrectomy and intraocular tamponade of silicone oil or C3F8 were included in this retrospective study. They were divided into silicone oil group and C3F8 groups. There was no statistically significant difference between these two groups of patients for gender, age, duration of diabetes, fasting glucose, history of hypertension, diabetic kidney disease history, history of cardiac and vascular diseases, body mass index and smoking history. There was statistically significant difference between these two groups of patients for visual acuity (Z=-2.604, P=0.009). There was no statistically significant difference between these two groups of patients for intraocular pressure before surgery (Z=0.064, P=0.949). The mean follow-up was (20.3±16.4) months with a range from 1 to 47 months. The patients were followed up for visual acuity, intraocular pressure, neovascular glaucoma (NVG), the incidence of retinal detachment, recurrent vitreous hemorrhage, and repeated operation for complications. ResultsVisual acuity (t=-3.932, -8.326; P=0.000, 0.000) and intraocular pressure (t=-3.159, -2.703; P=0.006, 0.009) were changed significantly after surgery for both groups. Between these two groups after surgery, there were significant differences of visual acuity (Z=-1.879, P=0.040), intraocular pressure (Z=-3.593, P=0.000), and complications (revision operation, retinal detachment, recurrent vitreous hemorrhage and NVG) (t=-2.777, -2.102, -2.308, -2.013; P < 0.05). ConclusionIntraocular silicone oil tamponade can reduce the postoperative complications of PDR, especially for severe retinal neovascularization, exudation associated with retinal edema.
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 evaluate the effect of vitreoretinal surgery with lens-sparing technique in treating the detachment with giant retinal tear(GRT) associated with proliferative vitreoretinopathy(PVR). Methods Thirty-one consecutive eyes with GRT unde rwent vitrectomy were analysed retrospectively. Operative techniques included peeling of pre-retinal membrane， injection of perfluorodecalin liquid， retinotomy and retinectomy，endolaser，and silicon oil or C2F6 gas tamponade. Lens-sparing vitrectomy was performed in 28 phakic eyes. Follow-up period ranged from 11 to 34 months. Results Anatomic retina l attachment was achieved intraoeratively in 29 eyes. In 16 eyes of 28 eyes with postoperative cataract formation,3 eyes underwent cataract surgery with or without intraocular lens implantation. The corrected final visual acuity ran ged from 0.4 to 0.01. Conclusion Most phakic eyes of retinal detachment with GRT PVR can be successfully operated on with an out come of improving the visual acuity by using techniques of lens-sparing vitrectomy, perfluorodecalin liquid and silcone oil tamponade. (Chin J Ocul Fundus Dis, 2001,17:93-95)