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 establish and evaluate a hydrocephalus model in dogs. Methods Twelve healthy adult male mongrel dogs (weight, 10-15 kg) were randomly divided into the control group (n=6) and the experimental group (n=6). All the dogs were given CT and neurological examination to exclude congenital ventricular enlargement and neurological abnormity before they received hydrocephalus induction. Surgical procedures included the exposing of the foramen magnum area, the opening of the atlantooccipita anadesma, and the injecting of silicone oil (0.3 ml/kg) into the fourth ventricle through a silicone tube. Normal saline was injected in the control group. The Tarlov neurological fitness assessment and the Evan’s ratio were used to evaluatethe degree of hydrocephalus at 3, 14 and 56 days after operation. Results In the experimental group, the dogs were dull and unsteady in walking,and they drank and ate less. The lateral ventricle began to expand 3 days afteroperation, and then the temple horn of the lateral ventricle and the third ventricle were also affected 14 days after operation. The ventricles were enlarged progressively after operation. The Tarlov scores measured at 3, 14 and 56 days afteroperation had a significant difference at the same time point between the control group(5.83±0.75，6.50±0.55，6.00±0.63) and the experimental group (4.00±0.89，4.83±1.17，4.50±1.05，P＜0.01), but had no significant difference within the same group at different time points (P＞0.05). The Evan’s ratios measured at 3, 14 and 56 days after operation were 0.33±0.04,0.39±006，0.44±0.03，respectively,in the experimental group; and were 0.27±0.06，0.25±0.09, 0.26±0.05,respectively,in the control group. There was a significant difference atthe same time point between the two groups, and at different time points within the experimental group (P＜0.05).Conclusion The dog model of hydrocephalus induced by the injecting of silicone oil into the fourth ventricle has a highsuccess rate, and the model is appropriate for the studies on diagnosis and therapy of hydrocephalus.
PURPOSE:To assess the effects of silicone oil removal on the complications associated with its use. METHODS:Retrospective analysis of the results of silicone oil removal after vitreous surgery for retinal detachment in 913 eyes in National Ophthalmology Centre of French. The follow-up period was at least six months and the mean duration of oil tamon- ade was 6.4 months. RESULTS :Retinal detachment recurred in 7.3%. The development of cataract continued after silicone oil removal. No patient retained a clear lens in the eye with oil remained in situ for more than 3 months. TWO of 5 eyes with keratopathy at the time of oil removal recovered after the oil removal ;but the corneas of another 4 eyes became dystrophic after the oil removal. Twelve of 15 eyes with secondary ocular hypertension incontrollable through medicinal treatment relieved after oil removal ,but another 11 eyes became hypertensive after oil removal. Persistent emulsive droplets wre found in anterior chamber angles of the above 11 hypertensive eyes and the 7 eyes with keratopathy. CONCLUSINOS:Early removal of silicone oil after retinal detachment operation might delay the development of cataract but can not avoid its occurence ,and ocular hypeitension and keratopathy can be prevented by early and complete removal of silicone oil. Chin J Ocul Fundus Dis,1997,13: 22-23）
Objective To compare the outcome of C3F8 versus silicone oil intraocular tamponade after pars plana vitrectomy (PPV) for the treatment of severe highly myopic macular hole retinal detachment (MHRD). Methods Thirty-two highly myopic MHRD patients (32 eyes) with extreme long axial lengths (ge;29.0 mm), quot;severequot; retina pigment epithelium (RPE) and chorioretinal atrophy, and posterior staphyloma who underwent PPV, were enrolled in this study. The patients were divided into two groups according to different intraocular tamponade agents: C3F8 (group A, 15 eyes) and silicone oil (group B, 17 eyes). The patients with retinal re-detachment after surgery received PPV again. The differences of sex (P=1.000), age (t=0.444, P=0.660), best-corrected visual acuity (t=0.084, P=0.934), diopter (t=0.449, P=0.978), lens state (P=1.000), time of the symptoms (t=0.375, P=0.710) and degree of retinal detachment (chi;2=0.014, P=0.907) between group A and B were not statistically significant. The anatomic reattachment of the retina, macular hole closure, and vision acuity were observed at one week, one, three, six and 12 months after surgery. Results The rates of retinal reattachment and macular hole closure were 60.00% and 13.33 % in group A, 82.35% and 29.41% in group B in the first time of surgery. There was no difference in rates of retinal reattachment and macular hole closure between two groups (P=0.243, 0.402). The rates of retinal reattachment and macular hole closure were 86.67% and 20.00% in group A, 94.12% and 29.41% in group B in the second time of surgery. There was no difference in rates of retinal reattachment and macular hole closure between two groups (P=0.589, 0.691). Twelve months after surgery, the vision acuity improved in five eyes, unchanged in seven eyes , and decreased in three eyes in group A; the vision acuity improved in seven eyes , unchanged in eight eyes , and decreased in two eyes in group B. The differences of vision result was not statistically significant between two groups (chi;2=0.209, P=0.647). Conclusion The rates of retinal reattachment and macular hole closure with silicone oil tamponade was higher than that with C3F8 tamponade in eyes with severe highly myopic MHRD, but the differences are not statistically significant.
Objective To evaluate the relative factors of effect of vitrectomy on corneal endothelial cells. Methods Retrospective analysis of the results of corneal endothelium microscopy performed on 213 eyes of 213 patients undergone vetrectomy operations including single vitrectomy (78 eyes), vitrectomy combined with cataract extraction (135 eyes), silicone oil injection (34 eyes), and C3F8 injection (53 eyes) before and after 1 week, 1 and 3 moths of these surgical procedures. Results There was no significant difference between pre- and postoperative corneal endothelium density in single vitrectomy group and vitrectomy combined with cataract extraction with posterior capsule integrity group (Pgt;0.05). The corneal endothelium density significantly decreased postoperatively in C3F8or silicone oil injection group with broken posterior capsule (Plt;0.05). Conclusion C3F8 and silicone oil may damnify corneal endothelium in patients undergo vitrectom y combined with cataract extraction with broken posterior capsule. (Chin J Ocul Fundus Dis，2004，20：101-103)
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)
Objective To observe the effect of emergent vitrectomy combined with lensectomy, silicone oil temponade for endogenous endophthalmitis. Methods The clinical data of 28 patients (30 eyes) with endogenous endophthalmitis were analyzed retrospectively. All patients had no history of ocular trauma and intraocular surgery history. There were 21 patients without systemic symptoms, three patients with fever, two patients with eye pain and headache, and two patients with abdominal pain when presentation. All patients diagnosed by best corrected visual acuity, intraocular pressure, slit-lamp microscopy, direct and indirect ophthalmoscope examination and intraocular B-ultrasound examination. Emergent surgery (vitrectomy, lensectomy, silicone oil temponade) was performed in all 30 patients, those with fever or abdominal pain was also treated by relevant clinical departments. Vitreous purulence was taken in all patients before vitrectomy for bacterial, fungal culture and drug sensitivity test. The follow-up was 18 to 30 months. The preoperative and postoperative visual acuity, intraocular pressure and eye retention situation were observed.Results Endophthalmitis was controlled in 28/30 eyes (93.3%) after surgery, recurrent vitreous empyema occurred in 2/30 eyes (6.7%). Evisceration was performed on those two eyes as uncontrolled intraocular pressure. The visual acuity improved significantly at one month and 18 months after surgery (chi;2=19.87, 32.44; P＜0.01). Postoperative intraocular pressure was normal in 24 eyes (80.0%), transient elevated and controlled in six eyes (chi;2=7.43；P＜0.05). 12/28 (42.9%) vitreous samples were positive for pathogen culture, including 7/12 (58.3%) positive for bacteria, 5/12 (41.7%) positive for fungi. There are 18/28 patients (64.3%) also had hepatobiliary system infections. Conclusion Emergent vitrectomy combined with lensectomy, silicone oil temponade is effective for endogenous endophthalmitis.
OBJECTIVE:To evaluate the toxicity of retinoic acid in silicone oil to the retinal tissue. METHOD:Twelve New Zealand white rabbits(24 eyes)were divided into three grorps at random. Three days after gas-compression vitrectomy,24 eyes were unedrgone gas/silicone oil exchange. The silicone oil 0.5 ml was injected intravitreally in 4 eyes as controls ,and 5mu;g/ml retinoic acid silicone oil 0.5ml in 10 eyes and 10 mu;g/ml retinoic acid silicone oil 0.5 ml in 10 eyes respectively as 2 study groups. After intravitrea[ injections, all the eyes were examined by ophthalmoscopy on the 1st, 3rd, 7th, 14th, 21st and 28th day. The retinas of the enucleated eyes on the 28th day were then examined by light microscopy and transmission electrone microscopy. RESULT: No evidence of toxicity was found in retinas after intravitreal injections of silicone oil with 5 mu;g/ml or 10 mu;g/ml retinoic acid. CONCLUSION :There was no toxic effect on the retinas by using 5 mu;g/ml or 10 mu;g/ml retinoic acid in intravitreal silicone oil tamponade operation. （Chin J Ocul Fundus Dis,1997,13: 81-82）
ObjectiveTo compare the effects of intravitreal tamponade of C3F8 with silicon oil on postoperative vitreous hemorrhage and visual prognosis after vitrectomy for proliferative diabetic retinopathy (PDR). MethodsThe clinical data of 121 patients (127 eyes) who underwent primary vitrectomy due to PDR were analyzed retrospectively. All the patients were divided into two groups according to different intravitreal tamponade, including C3F8 tamponade group (53 patients with 56 eyes) and silicone oil tamponade group (68 patients with 71 eyes). There was no difference of gender (χ2=0.956), age (t=1.122), duratiion of diabetes (t=0.627), fasting blood glucose (t=1.049), systolic pressure (t=1.056), diastolic pressure (t=0.517), history of hypertension (χ2=0.356), nephropathy (χ2=1.242), preoperative laser photocoagulation (χ2=1.225) and All the patients underwent three port pars plana vitrectomy. The mean follow-up was 2 years ranging from 6 months to 4 years. And then the incidence and onset time of postoperative vitreous hemorrhage and postoperative BCVA of the two groups were compared. ResultsPostoperative vitreous hemorrhage occurred in 14 of 56 eyes (25.00%) in C3F8 tamponade group. The average onset time of postoperative vitreous hemorrhage were (64.64±59.09) days ranging from 7-225 days and mostly were within 30-60 days (35.71%, 5/14). Postoperative vitreous hemorrhage also occurred in 7 of 71 eyes (9.89%) of silicone oil tamponade group after silicone oil removal with an average onset time of (25.29±20.46) days ranging from 3-65 days and were mostly within 15-30 days (42.86%, 3/7). There was a significant difference in the incidence of postoperative vitreous hemorrhage between the two groups (χ2=5.200, P<0.05). BCVA of the two groups was improved significantly after operation (Z=2.472, 3.114; P<0.05). Postoperative BCVA of silicone oil tamponade group was poorer than C3F8 tamponade group (Z=1.968, P<0.05). ConclusionBoth C3F8 and silicone oil tamponade can improve the visual acuity after vitrectomy for PDR. Compared with C3F8, silicone oil tamponade had lower incidence and late onset of postoperative vitreous hemorrhage after vitrectomy for PDR.
Objective To investigate the feasibility of using magnetic resonance imaging (MRI) to measure the visual axis length in silicone oil filled eyeballs. Methods Thirty-two silicone oil-filled eyes of 32 patients were studied. The antesilicone oil spaces (ASS) and retro-silicone oil spaces (RSS) on the visual axis was measured on the cross-sectional T1 weighted images (T1 WI) and T2WI, the length of the visual axis was measured on the fatsuppressed T2WI. The length of the visual axis was the distance from the corneal vertex to the macular fovea, and it was also measured by A-mode ultrasound in sitting position with different ultrasonic velocity. The postoil gap was also measured by A-mode ultrasound in supine position. Results Compared with the signal of the contralateral vitreous body, the silicone oil signal was higher on T1WI images, lower on T2WI images. After fat suppression, the silicone oil signal and chemical shift artifact were reduced. There were different levels of ASS and RSS in the vitreous cavity of all 32 cases, the RSS depth was (2.47plusmn;1.31) mm on average by MRI. However, RSS was detected in only 56.25% (18 cases)eyeballs by A-mode ultrasound. The visual axis length of silicone oil-filled eyes was (23.52plusmn;4.67) mm by MRI, and (20.57plusmn;5.32) mm by A-mode ultrasound in sitting position. The differences between two measurements was statistically significant (t=30.17, P＜0.05). Conclusions In addition to A-mode ultrasound, MRI might be another effective method to detect RSS and ASS, and to measure the axial length of silicone oil-filled eyes.