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.
Objective To observe the effect of pars plana vitrectomy (PPV) with epiretinal membrane peeling (ERMP) and (or) internal limiting membrane peeling (ILMP) and silicone oil tamponade for highly myopic macular hole retinal detachment (MHRD) with posterior staphyloma. Methods Eighty-five highly myopic MHRD patients (85 eyes) were enrolled in this study. All the patients were examined for corrected visual acuity (CVA), slit lamp microscope and preset lens, indirect ophthalmoscope, A/B ultrasound, optical coherence tomography (OCT) and intraocular pressure examination. The average axial length was (29.1plusmn;1.8) mm. There were 24 eyes with diffuse choroid atrophy and 61 eyes with partial choroid atrophy. The CVA was converted into a logarithm of the minimal angle of resolution (logMAR) for statistical analysis. The average logMAR CVA was 1.93plusmn;0.37. All the patients were treated with PPV and triamcinolone acetonide or indocyanine green (ICG) assisted ILMP and (or) ERMP and silicone oil tamponade. TA assisted ERMP was performed in 21 eyes; with ICG assisted ILMP in 56 eyes and TA assisted ILMP in eight eyes. The duration of silicone oil tamponade was (6.2plusmn;1.6) months. CVA, retina and macular hole status and complications were observed postoperatively. Differences between preoperative and postoperative CVA were evaluated by the t test and correlation analysis. Multiple logistic regression analysis was performed to assess the influence of individual preoperative factors on the initial anatomical success. Differences in the macular hole closure rate between eyes with or without macular schisis were evaluated for statistical significance using corrected chi-square. Results The mean logMAR CVA was 1.34plusmn;0.48 after surgery, which significantly improved compared to that before surgery (t=39.38, P＜0.01). The CVA after surgery was independent of axial length (r=0.142, P＞0.05), choroid atrophy (t=0.23, -0.165,P＞0.05) and macular hole closure (t=0.12, -0.005, P＞0.05). The retina reattached in 79 eyes (92.9%) and recurrence of retinal detachment occurred in six eyes (7.1%). Multiple logistic regression analysis indicated that recurrence of retinal detachment was independent of choroid detachment, proliferative vitroretinopathy, axial length, choroid atrophy and ILMP (OR=1.428, 5.039, 0.815, 2.578, 0.432; P＞0.05). Of these 85 eyes, macular hole closed in ten eyes (11.8%), macular hole did not close in 75 eyes (88.2%). There were 24 eyes (28.2%) experienced high intraocular pressure during the first 2 weeks after surgery, all of them were under control with drugs. There were 12 eyes (14.1%) presented with high intraocular pressure before the silicone oil removal, all of them were under control only by silicone oil removal. Conclusion For the treatment of MHRD with posterior staphyloma, PPV combined with ERMP and (or) ILMP and silicone oil tamponade show a high retinal reattachment rate.
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)
Objective To verify the changes of optics and refraction of the eyes after retinal detachment surgery with the tamponade of silicone oil in vitreous cavity. Methods The optical calculation was taken as the following by using the parameter of Gullstrand model eye:（1）The refraction of silicone filled eye in non-accommodative status;（2）The refraction of silicone filled eye in non-accommodative status;（3）The aniseikonia analysis when one eye filled with the silicone oil;（4）The IOL power re-calculation． Results （1） Compa red with the normal eye,the eye filled with silicone oil is moved toward high hyperopia of +9．19 D;（2）When corrected,the accommodation amplitude reduced 1.42 D induced by filling silicone oil. Conclusion When eye filled with silicone oil,the change of refractive power tends to be highly hyperopic,the amplitude of accommodation decreased,and the regular IOL power calculation formula is no longer available. (Chin J Ocul Fundus Dis，2000，16：139-212)
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）
Objective To investigate the main causes and risk factors of recurrent retinal detachment (RRD) after silicone oil removal (SOR) in eyes with complex retinal detachment. Methods It was a retrospective case series study. A total of 458 eyes of 455 consecutive patients who underwent pars plana vitrectomy with silicone oil tamponade were recruited in this study. All patients underwent vitrectomy operation. Additionally, they were given heavy water, membrane peeling, retinotomy or partial cutting, intraocular laser photocoagulation or frozen, gas-liquid exchange or direct oil exchange operation accordingly. Ninety-eight eyes with multiple holes, old retinal detachment, hyperplasia and serious traction lesions underwent scleral buckling surgery simultaneously. Intravitreal silicone oil was padded at the end of operation. Cutting, stripping or resection and 360° preventive laser photocoagulation were applied while the epiretinal membrane was found and need treatment during SOR. Holes or suspicious hiatus underwent intraocular laser photocoagulation or cryotherapy during the operation. One week after SOR and during follow-up, the visual acuity, intraocular pressure (IOP), slit lamp microscope, and ophthalmoscope examination were examined with the same technique and methods as preoperation. The eyes were divide into two groups based on the attachment status of retina after SOR, which were reattached group (419 eyes) and redetached group (39 eyes) respectively. The following data were recorded: the age of patients, ocular axial length, logarithm of minimum angle of resolution (logMAR) best corrected visual acuity (BCVA) and IOP before vitrectomy operation and before and after SOR, the number of retinal breaks, the duration of silicone oil filling, the duration of followup, and the related factors during vitrectomy operation and SOR. The relation of age, sex, high myopia, the size and location of holes, aphakic eye, proliferative vitreoretinopathy (PVR) C3 level and above, previous history of failed retinal detachment operation, 360° preventive laser photocoagulation, assistant scleral buckling surgery, SOR via corneal puncture to RRD after SOR were analyzed. Odds ratio (OR) and its 95% confidence interval (CI) were calculated for the age ＜40 years old and gender. High myopia, assistant scleral buckling surgery and SOR via corneal puncture were further analyzed by multiple regression equation. Results After SOR operation, the total average logMAR BCVA was 0.86±0.63. The average logMAR BCVA was 0.82±0.59 and 0.99±0.70 respectively for the reattached and redetached groups, which was not statistically different (F=1.559,P＞0.05). The number of high myopia eyes in the reattached and redetached groups were 116 and 22 eyes, respectively, accounted for 27.7% and 56.4%, and the difference was statistically significant (χ2=13.984,P＜0.01). Three eyes underwent vitrectomy with scleral buckling occured RRD, accounting for 3.1%; while 36 eyes underwent vitrectomy without scleral buckling occured RRD, accounting for 10.0%. The incidence of RRD between them was statistically significant (χ2=4.761,P＜0.05). The incidence of RRD was not retated to the PVR levels before the operation, previous history of failed retinal detachment operation, aphakic eye and preventive laser photocoagulation (OR=1.626, 1.699, 1.986, 0.709; 95%CI:0.836-3.162, 0.832-3.658, 0.921-4.279, 0.268-1.875; P＞0.05) . RRD had a close relation with high myopia and assistant scleral buckling surgery (OR=3.380, 0.284; 95%CI:1.733 -6.595, 0.086-0.944; P＜0.05). The raise of risk derived from SOR via corneal puncture had no statistical significance (OR=2.119; 95%CI: 1.043-4.306; P＞0.05). The incidence of RRD after SOR was 8.5%; of which, 35.9% originated from new breaks and 69.2% were related to new breaks, in contrast, only 5.1% originated from PVR but 51.3% were related to PVR. ConclusionsHigh myopia is an independent prognostic risk factor of RRD after SOR. Combined scleral buckling surgery is a protective factor of RRD after SOR. To the well reattached eyes before SOR, the new breaks seems to be the main cause of RRD, wheras PVR was probably a secondary phenomenon.
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 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 investigate the characteristics and risk factors of optic nerve atrophy in eyes with complicated retinal detachment after silicone oil tamponade during the procedure of vitreoretinal operation. Methods The clinical data of 97 patients with complicated retinal detachment who had optic nerve atrophy after silicone oil tamponade during the procedure of vitreoretinal operation were an alyzed retrospectively. Logistic regression analysis by SPSS statistical software was used to analyze the factors like age, disease history, primary diseases, preoperative ocular condition, complications in and after the operation, the time taking out the silicone oil, and emulsification of the silicone oil, and Ple;0.05 was considered to be the symbol of significant difference. Results All of the affected eyes had optic discs with clear border, including paler optic disc in 65 eyes, pale one in 21 eyes, and paler optic disc with enlargement of the cup/disc (ge; 0.6) in 11 eyes. The result of logistic regression analysis showed that the intraocular pressure (P=0.022) and the visual acuity (P=0.001) during the silicone oil removal were in the equation. Conclusion The risk factor of optic nerve atrophy is the chronic increase of intraocular pressure after silicone oil tamponade. (Chin J Ocul Fundus Dis, 2006, 22: 305-307)
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.