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At least 19 recordsLinked to original sources
PubMed1997

Interaction between silicone oil and silicone intraocular lenses: an in vitro study.

The objective of this study was to examine the interaction between silicone oil and silicone intraocular lenses (IOLs) in vitro. Six types of silicone IOLs were placed in silicone oil (1000 or 5000 centistokes) for 1 minute, 7 days, and 420 days. Slit-lamp examination, target photographs, and opacity measurements were performed. Optical measurements were repeated in a balanced salt solution after removal from the oil. The IOL surface was examined through scanning electron microscopy, and surface irregularities underwent x-ray spectroscopy. No changes were observed while the IOLs were stored in silicone oil, but in the balanced salt solution, the IOLs were observed to have a layer of silicone oil droplets that reduced the optical quality. Scanning electron microscopy showed that oil-coated foreign body particles were simulating IOL surface defects. After ultrasonic cleaning with ethanol, the oil layer was broken, and no damage to the IOL surface could be detected. The length of exposure to silicone oil, the type of oil, and the type of IOL were found to have no bearing on the interaction between silicone oil and silicone IOLs. Although no surface damage is incurred by silicone IOLs from silicone oil, the reduction in optical quality and fundus view due to remnant oil droplets seems to indicate that complex cases requiring silicone oil injection may contraindicate IOLs made of silicone.

Adhesiveness↗
PubMed1984

Experimental model of proliferative vitreoretinopathy (PVR) in the vitrectomised eye: effect of silicone oil.

Silicone oil alone or as an adjunct to vitrectomy is widely used for the treatment of retinal detachment complicated by proliferative vitreoretinopathy (PVR). It appears to reduce the tendency for recurrent traction detachment, but the mechanism of this action is obscure. We have studied the effects of silicone oil in an experimental animal model. Twenty five thousand homologous fibroblasts were injected into the aphakic vitrectomised rabbit eye, and traction detachment of the vascularised retina (medullary rays) regularly resulted. Intraocular silicone oil did not influence the development of this experimental detachment.

Animals↗
PubMed2007

Interaction with intraocular lens materials: does heavy silicone oil act like silicone oil?

PURPOSE: To determine the interaction of heavy silicone oil with various intraocular lens (IOL) materials and whether heavy silicone oil covers the silicone IOL optic as silicone oil does. SETTING: Department of Ophthalmology, Dokuz Eylul University, Izmir, Turkey. METHODS: The study group comprised 5 poly(methyl methacrylate) (PMMA) IOLs, 4 foldable silicone IOLs, 5 foldable hydrophilic acrylic IOLs, and 5 foldable hydrophobic acrylic IOLs. Each IOL was bathed in balanced salt solution (BSS) for 10 minutes and then placed in heavy silicone oil dyed with Sudan Black for another 10 minutes. Afterward, each IOL was reimmersed in BSS for 5 minutes and examined under the light microscope. Digital images were analyzed to determine the optic area covered with heavy silicone oil. RESULTS: The mean heavy silicone oil coverage was 7.05% +/- 7.88% (SD) (range 1.13% to 20.54%) on PMMA IOLs, 100% on silicone IOLs, 12.17% +/- 11.43% (range 1.25% to 31.52%) on hydrophobic acrylic IOLs, and 34.64% +/- 13.28% (range 12.57% to 44.42%) on hydrophilic acrylic IOLs. Heavy silicone oil coverage of silicone IOLs was statistically significantly greater than the coverage of other IOL materials. CONCLUSION: Heavy silicone oil acted the same as silicone oil and covered the entire surface of silicone IOLs.

Acrylic Resins↗
PubMedDate not supplied

Physical properties of vitamin E oil and silicone oil.

A comparison of the physical properties of vitamin E oil and silicone oil is made. The parameters measured include: viscosity, fluid density, refractive index and wetting characteristics of the water/liquid interface. These properties showed remarkable similarities between vitamin E oil and silicone oil.

Densitometry↗
PubMed1995

The effect of molecular weight and gel preparation on humoral adjuvancy of silicone oils and silicone gels.

Silicone gels from commercial breast implants have been shown previously by our laboratory to be potent humoral adjuvants, while the low molecular size 20 centistoke (cs) silicone oil (M.W. 1900) possesses no measurable adjuvant properties. It became necessary to shear the silicone gel during our previous experiments in order to facilitate injection through a syringe and needle, it is conceivable that shearing may reduce the molecular weight of the silicone gel used. This investigation was undertaken to determine whether humoral adjuvancy of silicone oils is dependent on molecular weight and whether the method of shearing the silicone gel affects its adjuvancy. Four Dow Corning 360 Medical silicone oils (100 cs, M.W. approximately 5,000; 350 cs, M.W. approximately 10,000; 1000 cs, M.W. approximately 16,500 and 12,500 cs, M.W. approximately 60,000) and Dow Corning octamethylcyclotetrasiloxane (D4, M.W. 296) were tested for their humoral adjuvancy by immunizing 64 Sprague Dawley rats with 50 micrograms of bovine serum albumin (BSA) mixed with each oil. The rats were periodically bled and the sera were analyzed for anti-BSA antibodies by ELISA. In a separate experiment, three silicone gel preparations with reproducible characteristics were prepared by using a tissue homogenizer and varying the applied shear force. Each of these preparations was tested for its humoral adjuvancy as previously described for silicone oils. Rats immunized with BSA mixed with the highest molecular size silicone oil tested (M.W. approximately 60,000) showed a significant increase in anti-BSA antibodies as compared to the lower molecular size oils. The three silicone gel preparations showed no difference in their adjuvancy effect. Thus, the humoral adjuvancy of silicone oil appears to be dependent on molecular weight. Differential shearing of the silicone gel does not alter its humoral adjuvancy.

Adjuvants, Immunologic↗
PubMed1994

The effects of silicone oil removal. Silicone Study Report 6.

OBJECTIVE: To evaluate the advisability of removing silicone oil from eyes after surgery for severe (with a classification of at least C-3) proliferative vitreoretinopathy. DESIGN: Subgroup analysis of the Silicone Study, a randomized, multicentered, surgical trial. SETTING: Community- and university-based clinics. PATIENTS: Two hundred twenty-two eyes with severe proliferative vitreoretinopathy followed up in the Silicone Study. INTERVENTIONS: Vitrectomy for proliferative vitreoretinopathy with silicone oil as the intraocular tamponade. OUTCOME MEASURES: Changes in visual acuity, recurrent retinal detachment, and incidence of complications. RESULTS: Ninety-nine (45%) of 222 eyes had surgery for silicone oil removal (oil-removed eyes). Compared with the eyes that did not undergo silicone oil removal (oil-retained eyes) evaluated at a comparable time after oil injection, oil-removed eyes at the examination prior to oil removal were more likely to be attached (85% vs 40%; P < .0001), have a visual acuity of 5/200 or greater (63% vs 35%; P < .0001), and not be hypotonous (5% vs 22%; P < .001). There was no association between the length of oil retention and incidence of recurrent retinal detachment after oil removal. Eyes with attached retinas at the time of oil removal generally improved in visual acuity at the last follow-up examination (P < .0001), which was not evident in eyes with detached retinas at the time of oil removal. In a matched-pair cohort analysis comparing both sets of eyes, there was an increased risk for recurrent retinal detachment at the last follow-up examination in the oil-removed eyes (odds ratio [OR], 2.1; P = .09). However, overall visual acuity improved for oil-removed eyes in 19 (29%) of 66 pairs and for oil-retained eyes in one (2%) of 66 pairs (OR, 19.0; P < .0001). Although nonsignificant, incidence rates of keratopathy (OR, 0.5) and hypotony (OR, 0.5) were lower in oil-removed eyes. CONCLUSION: Removal of silicone oil in anatomically successful eyes significantly increases the likelihood of improved visual acuity with a slight increase in the likelihood of recurrent retinal redetachment. There was a trend for a reduction in the incidence of complications in the oil-removed eyes.

Adult↗
PubMed1998

29Si imaging of silicone breast implants and intraocular silicone oil.

Silicon-29 (29Si) imaging was investigated as a potential imaging modality for monitoring silicone prostheses in humans. The 29Si relaxation times of several silicone gels were measured and found to average T1 = 21.2 +/- 1.5 s and T2 = 207 +/- 40 ms, with no significant difference between virgin and explanted gels. A single-shot half-Fourier rapid acquisition with relaxation enhancement (RARE) and a refocused gradient-echo sequence were used for acquiring 29Si images with 5 x 5 mm2 resolution and no slice selection. Three volunteers with silicone-gel-filled breast implants and one subject with an intraocular silicone oil injection were thus examined in a total acquisition time of 10-15 min per image. On all 29Si images, the shape of the silicone object was well depicted. Although at present, conventional proton images are superior in resolution and signal-to-noise ratio, 29Si imaging has the advantage of optimal specificity, since only the silicone itself is visible.

Biocompatible Materials↗
PubMed2006

Re-emergence of hidden residual intraocular silicone oil bubble after previous silicone oil removal.

BACKGROUND: We describe the re-emergence of a hidden residual intraocular silicone oil bubble after previous silicone oil removal. HISTORY AND SIGNS: A 57-year-old patient underwent vitrectomy with silicone oil for a complicated retinal detachment. Six weeks later silicone oil was removed via the pars plana and phakoemulsification with lens implantation was performed. Subsequent clinical follow-up showed an attached retina without residual silicone oil bubbles. However, more than 2 years later the patient suffered sudden visual loss. Clinical examination showed a bubble of silicone oil wedged between a remaining layer of anterior vitreous and the capsular bag, reducing central visual acuity. THERAPY AND OUTCOME: Complete extraction of the silicone oil bubble was performed via the pars plana. CONCLUSIONS: Residual silicone oil bubbles may wedge themselves into vitreous pockets in the ophthalmoscopically invisible regions of the pars plana. Over time these bubbles may migrate into the retrolental space with obstruction of the visual axis.

Drainage↗
PubMed1996

Irreversible silicone oil adhesion to silicone intraocular lenses. A clinicopathologic analysis.

PURPOSE: To report a newly defined complication of foldable intraocular lenses (IOLs), namely silicone oil-silicone IOL interaction. This is a complication not generally seen by the implanting cataract surgeon but, rather, at a later stage in a patient's postoperative course, by a vitreoretinal surgeon. METHODS: Three clinical case histories, including two explanted silicone IOLs, were submitted for analysis. The submitted silicone lenses were photographed under water, and the nature of the silicone oil coating was documented. RESULTS: In each instance, the silicone coating was manifest as a thick coating with droplet formation on the lens surface that was tenaciously adherent and could not be dislodged by instruments or injection of viscoelastics. CONCLUSION: The use of silicone IOLs in patients with current vitreoretinal disease or those who are at high risk for future vitreoretinal disease that may require silicone oil as part of the therapy should be reconsidered. The authors recommend that information regarding the existence and significance of this complication be printed on all silicone oil and silicone IOL packages and inserts (if not as a warning, at least as an informative comment regarding the existence of this condition). This is a rare but clinically significant complication that will affect the occasional patient treated with both of these modalities.

Adult↗
PubMedDate not supplied

Clinical consequences of the use of highly purified silicone oil. Comparative study of highly and less purified silicone oil.

PURPOSE: To compare the ocular toxicity caused by the use of highly purified silicone oil to less purified silicone oil in humans. METHODS: Fifty-six eyes received 2,000 centistokes (cs) purified silicone oil (group 1) and 42 eyes received 2,000 cs fractionated (highly purified) silicone oil (group 2) after pars plana vitrectormy. Follow-up ranged from 6 to 48 months. RESULTS: Six months after injection, the following complications were found in groups 1 and 2, respectively: ocular hypotension (< 13 mmHg), 39.3% and 31%, sustained ocular hypertension (> 23 mmHg), 19.6% and 19%; acute hypertensive peaks (> 30 mmHg), 23.2% and 11.9%; corneal alterations, 19.6% and 14.3%; emulsification, 1.8% and 2.4%; silicone oil cloudiness, 28.6% and 0%; preretinal reproliferation, 14.3% and 4.8% and total or partial retinal reattachment, 78.6% and 90.5%. CONCLUSIONS: Highly purified silicone oil was better tolerated than the less purified oil and caused fewer complications. Poorly purified silicone oils should be avoided in clinical practice.

Aged↗
PubMed1993

[Observations on vitrectomy with silicone oil injection].

Silicone oils were injected in 37 eyes of 37 patients among 95 patients performed vitrectomy during 1988-1990. The indication was complicated retinal detachment except for 2 cases of diabetic proliferative retinopathy and vitreous hemorrhage. In 29 (78.4%) of the 37 eyes, the retina was totally reattached, and in 7 eyes partially reattached that did not regain ambulatory vision. In 22.7% of the eyes successfully operated, cataracts developed with silicone oil 1,000mPa.s while transient hypertension occurred in 27.3% with silicone oil 5,000mPa.s. Vitrectomy with silicone oil filling may help some retinal detachments that are refractory to conventional retinal and vitreous operations; however, due to possible complications, the use of silicone oil should be in limited cases and removed after retinal reattachment.

Adult↗
PubMed2000

Migration of silicone oil into the brain: a complication of intraocular silicone oil for retinal tamponade.

PURPOSE: To report a case in which intravitreal silicone oil migrated along the intracranial portion of the optic nerve and into the lateral ventricles of the brain after the repair of a retinal detachment secondary to cytomegalovirus retinitis. METHODS: A 42-year-old man with acquired immunodeficiency syndrome (AIDS) developed a rhegmatogenous retinal detachment in his left eye secondary to a cytomegalovirus infection of the retina. The detachment was repaired using 5000 cs intraocular silicone oil for a long-term tamponade. Subsequently, the affected eye developed glaucoma, which was poorly controlled. Fifteen months after the retinal surgery, he developed a peripheral neuropathy that was thought to be AIDS related. Computed tomography and magnetic resonance imaging of the head were performed to investigate the neuropathy. RESULTS: The patient was found to have a foreign substance within his lateral ventricles that shifted with position and was identical with respect to its imaging properties to the remaining intraocular silicone oil. Additional material was found along the intracranial portion of his optic nerve. CONCLUSION: Under certain circumstances, intraocular silicone oil may migrate out of the eye, along the intracranial portion of the optic nerve, and into the lateral ventricles of the brain.

AIDS-Related Opportunistic Infections↗
PubMed2004

[The effect of phacoemulsification combined silicone oil remove and intraocular lens implantation on the eyes with silicone oil temponade].

PURPOSE: To study the effect of phacoemulsification combined silicone oil remove and intraocular lens implantation on the eyes with silicone oil temponade. METHODS: Forty cases (41 eyes) performed phacoemulsification combined silicon oil remove and intraocular lens implantation were retrospectively studied and followed back for 2-18 months, analysis the recover of eyesight and complication of postoperation and during the operation. RESULTS: Except three cases had retina detachment after silicone oil remove, all others patients improved the eyesight in some degree. The main complication during the operation was the posterior capsule tear. The complication of postoperation was retinal detachment. CONCLUSION: It is an effective and safe way that the phacoemulsification combined silicone oil remove for eyes with silicone oil temponade.

Aged↗
PubMed1987

Silicone oil removal. I. The effect on the complications of silicone oil.

The results of a retrospective study of the effects of silicone oil removal from 85 eyes in 85 patients are reported. Pars plana vitrectomy and fluid/silicone oil exchange had been undertaken for retinal detachments associated with giant retinal tears or with proliferative vitreoretinopathy in all cases. Clinically significant cataract developed in 60% of lenses that were clear at the time of oil removal, and 85% of pre-existing lens opacities progressed. Removal of oil from 19 eyes with uncontrollable glaucoma was combined with drainage surgery in 14 eyes. Postoperatively the intraocular pressure was controlled in 13. Corneal decompensation either improved or was unchanged in eight out of nine patients after silicone oil removal, and three patients had penetrating keratoplasty and maintained a clear corneal graft. Patients who did not have glaucoma or keratopathy at the time of silicone oil removal did not develop these complications.

Cataract↗