PURPOSE:To evaluate the ability Of retinoic acid(RA) in silicon oil(SiO)to inhibit the proliferation of injected intraocular fibroblast cells. METHODS:Thirty New Zealand white rabbits (58 eyes)were divided into three groups. In control group ,only SiO(10 eyes)or BSS(10 eyes)were injected intravitreally and 5mu;g/ml (18 eyes)or 10mu;g/ml (20 eyes)RA in SiO were injected into other lwo groups respectively. Three days after gas-compression vitrectomy, 2 times;105 fibroblasts and Sio(0.5ml)or BSS(0.5ml)were injected in all eyes sequentially.The morbidity of tractional retinal detachment (TRD) were observed by ophthalmoscope until 4 weeks. RESULTS:After 4 weeks,in control ,5mu;g/ml RA in SiO and 10mu;g/ml RA in SiO group,80. 00%,44.44%,and 30.00% eyes developed TRD respectively. Significant statistical differences were found between the control group and the two treated groups (P＜0.05). CONCLUSIONS:5mu;g/ml or 10mu;g/ml RA in SiO can inhibit the occurrence of TRD effectively. （Chin J Ocul Fundus Dis,1997,13:174-176）
Objective To investigate the effect of prophylactic 360°laser retinopexy on retinal redetachment after silicone oil removal. Methods The clinical data of 181 vitreoretinal patients after silicone oil removal were retrospectively analyzed. In 88 patients (photocoagulation group) was taken prophylactic 360-degree laser retinopexy before silicone oil removal; in 93 patients (control group) without prophylactic laser retinopexy. The incidence, time, the cause of retinal redetachment and the complications of laser retinopexy after silicone oil removal in two groups were observed. Results The duration of silicone oil tamponade is 4~72 weeks, averaging 13.7±2.4 weeks. 20 cases of retinal redetachment were recorded after silicone oil removal, including 5 cases (5.7%) in photocoagulation group and 15 cases (16.1%) in control group. The difference between two groups is statistically significant (Plt;0.05). Among these 20 patients with retinal redetachment, 10 occured during the first 3 days after the operation, 6 during 4~7 days, 3 during 8~14 days. 1 case occured 2 months after the operation. 11 cases of redetachment result from the omission of small retinal breaks located in ora serrata or behind the photocoagulation zone, or the reopening of primary retinal breaks because of insufficient photocoagulation and freezing during the operation. 1 case result from the hole that come from laser photocoagulation scar tracted by nearby proliferative tissue. 7 cases result from the formation of new breaks from the proliferative vitreoretinopathy(PVR) or proliferation of residual vitreous. There are 52 cases of burning of pupillary border, with the incidence of 59%. Conclusions Prophylactic 360-degree laser retinopexy is associated with a decrease of the incidence of retinal redetachment after removal of silicone oil. （Chin J Ocul Fundus Dis，2008，24：283-285）
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 observe the effects of vitrectomy combined with endotamponade on severe endophthalmitis. Methods The clinical data of 44 patients (44 eyes) of posttraumatic and 22 patients (22 eyes) of postoperative severe endophthalmitis were retrospectively analyzed. All patients were treated by vitrectomy and endotamponade. Intraocular foreign body removal (19 eyes), lens extraction (25 eyes), intraocular lens removal (six eyes) and scleral buckling (16 eyes) were performed. Tamponade with silicone oil (52 eyes) or C3F8 gas (14 eyes) was also performed. Postoperative follow-up ranged from two to 25 months, with the mean of 7-9 months. The visual acuity（VA）and intraocular pressure before and after surgery were comparatively analyzed. Results Inflammation of all the patients were controlled，the effective rate was 5.10%. There was no recurrence and retinal detachment. Among the 66 eyes, postoperative VA of 58 eyes (87.90%) increased,five eyes（7.60%）didn't change and three eyes（4.55%）decreased, the difference was statistically significant（chi;2=45.27，P＜0.05）. The postoperative intraocular pressure was higher than that before surgery，the difference was statistically significant（t=-3.23，P＜0.05）. Conclusions Vitrectomy combined with endotamponade is an effective way to cure severe endophthalmitis. It can improve the visual acuity and intraocular pressure.
Objective To invesligate the treatment of retinal de tachment(RD) after silicone oil tamponades(SOT)． Methods The records of a consecutive series of 32 eyes with redetachment of retina after SOT surgery between 1998 to 2000 were reviewed retrospectively． The surgical techniques used for these cases included remove of silicon oil,peeling of preretinal membrane, retinotomy, endolaser photocoagutation, secondary vitrectomy and C3 F8 tamponades． Results In 28 of 32 eyes the retina was reattached (87．6%)． The postoperative visual acuity was improved in 12 eyes, redused in 4 eyes and remained no change in 16 eyes． The postop erative complications in 6 eyes included secondary glaucoma(3 eyes), hypotony (1 eye) and hyphema (2 eyes)． Conclusion The techniques of preretinal membrane peeling, retinotomy, endophotocoagulation and C3 F8 tamponades can be effectively used in combination to treat the redetachment of retina after the silicone oil tamponades surgery． (Chin J Ocul Fundus Dis,2001,17:214-215)