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PubMed1995

[Intraocular silicone lenses and silicone oil].

BACKGROUND: Foldable silicone intraocular implants are becoming more popular in conjunction with small incision phacoemulsification. PATIENTS: We observed three patients with silicone oil droplets adherent to the posterior surface of the silicone implant, following silicone oil removal after preceding vitreoretinal surgery with the installation of silicone oil. These droplets could not be dislodged intraoperatively either with focal aspiration or irrigation. They interfered with the patients subjective visual acuity. For this reason, we performed an exchange of the silicone intraocular implant against a PMMA one-piece lens in all three cases. RESULTS: This procedure resulted in an increase of the visual acuity. The mechanism of adherence between the two silicone polymers is finally not known. CONCLUSIONS: With increased use of implantable silicone intraocular lens and silicone oil this complication may be encountered more frequently. Therefore, implantation of silicone lens in vitreoretinal high risk eyes should avoided.

Aged↗
PubMed2004

Immobilisation and synthesis of DNA on Si(111), nanocrystalline porous silicon and silicon nanoparticles.

Oligonucleotides have been synthesized on hydrogen-terminated Si(111) and porous silicon using surface hydrosilation of difunctional molecules (1,(omega)-dimethoxytritylundecenol) to produce a monolayer bearing suitable reactive groups to allow automated solid-phase DNA synthesis. The absence of an intervening oxide enables electrochemical characterisation of the surface-bound oligonucleotides. Complementary sequences to the DNA synthesized on Si(111) undergo hybridisation at the surface and a straightforward electrochemical quantitation of the amount of synthesized DNA and its hybridisation efficiency (47%) is possible using Ru(NH3)6(3+) as a redox label. In the case of DNA synthesized in porous silicon, electron transfer (ET) between DNA and the underlying bulk semiconductor can be studied by cyclic voltammetry, however the anisotropic diffusion inside the porous layer and the large resistance of the porous silicon results in voltammograms for which thin-layer behaviour is not observed and the peak currents increase with the square root of scan rate. We interpret these voltammograms in terms of charge transport limitations in the layer of metal centres bound to the DNA inside the pores. Further evidence for this interpretation has been obtained using scanning electrochemical microscopy (SECM) to study the charge transport between redox species in films of DNA synthesized on Si(111) surfaces that are in contact with an aqueous phase. As the bulk concentration of Ru(NH3)6(3+) is reduced below about 250 microM the SECM feedback indicates that the rate of charge transport between surface-bound Ru(NH3)6(3+) exceeds that due to diffusion in the liquid phase. Electrochemical quantitation of the DNA is not possible in this situation, however we have been able to obtain independent determinations using radioassay based on 32P or UV/VIS spectrophotometry of dimethoxytrityl cation cleaved from the porous layer. In the case of the former, use of labelled complementary sequences shows an inverse relationship between the current density used to prepare the porous silicon and the amount of hybridisation. This can be interpreted in terms of the specific surface area of the porous silicon layers since the hybridisation efficiencies (ca. 40%) obtained by comparing DMT+ cleaved from sequences synthesized on the surface and then from complementary sequences after hybridisation were relatively insensitive to the current density used to prepare the layers. Our recent work has also been concerned with individual Si nanocrystals generated by breaking up porous silicon during thermal hydrosilation reactions. FTIR spectroscopy shows these particles are also coated with an organic Si-C-bonded monolayer and they form stable, non-turbid and strongly luminescent (lambdamax = 600-650 nm) dispersions in apolar solvents (L. H. Lie, M. S. Duerdin, E. M. Tuite, A. Houlton and B. R. Horrocks, J. Electroanal. Chem., 2002, 538/539, 183). The effect of carrying out synthetic reactions on the porous silicon prior to breaking up the layer is to produce instead larger, micron-scale assemblies with a nanometre scale internal structure. Micron-sized particles of porous silicon produced by breaking up the layer can be probed by confocal Raman spectroscopy using the electric field of a focused laser to trap such particles. Although these particles are also luminescent, the use of relatively long wavelength laser excitation (lambda = 785 nm) allows acquisition of Raman spectra from individual particles in the optical trap. The bulk optical phonon mode at ca. 520 cm(-1) characteristic of crystalline silicon is red-shifted and broadened providing evidence for an internal nanometre scale substructure in these micron-sized particles and we also see evidence for this mode in the colloidal suspensions of the Si nanoparticles. We propose a model for the formation of these two types of particles and briefly discuss the prospects to extend our solid-phase synthesis on porous silicon to allow the facile synthesis of luminescent Si nanocrystals bearing DNA or other biomolecules.

Crystallization↗
PubMed2001

Silicone gel breast implant rupture, extracapsular silicone, and health status in a population of women.

OBJECTIVE: To assess whether breast implant rupture or extracapsular silicone are associated with selected symptoms of self-reported physician-diagnosed connective tissue disease (CTD). METHODS: Women with silicone gel breast implants responded to a questionnaire that included questions on health status, satisfaction with implants, symptoms of CTD, and physician-diagnosed disease. These women then had magnetic resonance imaging (MRI) of their breasts to determine the status of the implants with respect to rupture and extracapsular silicone. RESULTS: Women with breast implant rupture diagnosed by MRI were no more likely to report a diagnosis of selected CTD than those with intact implants or those with implants of indeterminate status. Women with extracapsular silicone (silicone gel outside of the fibrous scar that forms around breast implants) were more likely to report having fibromyalgia (FM, p = 0.004) or other CTD, which included dermatomyositis, polymyositis, Hashimoto's thyroiditis, mixed CTD, pulmonary fibrosis, eosinophilic fasciitis, and polymyalgia (p = 0.008) than other women in the study. The association with FM remained statistically significant when adjusted for multiple comparisons (7 diagnoses) and implant age, implant location, or implant manufacturer (p < 0.05 in all cases), but became of borderline statistical significance when adjusted for multiple comparisons and self-perceived health status (p = 0.094) or self-perceived rupture status (p = 0.051). The association with other CTD remained statistically significant when adjusted for multiple comparisons and implant location or implant manufacturer, but became borderline or insignificant when adjusted for multiple comparisons and for implant age (p = 0.051), self-perceived health status (p = 0.434), or self-perceived rupture status (p = 0.145). Logistic regression was used to compute odds ratios of self-reported diagnoses comparing women with and without extracapsular silicone. The odds ratios were 2.8 (95% CI 1.2 to 6.3) for FM, and 2.6 (95% CI 0.8 to 8.5) for other CTD after adjustment for implant age, implant location, implant manufacturer, implant type, self-perceived health, self-perceived rupture status, and site of surgery practice. CONCLUSION: These data suggest an association between extracapsular silicone from ruptured silicone breast implants and FM. If this association persists in other studies, women with silicone gel breast implants should be informed of the potential risk of developing fibromyalgia if their breast implants rupture and the silicone gel escapes the fibrous scar capsule.

Adult↗
PubMed2003

Silicon-silica nanowires, nanotubes, and biaxial nanowires: inside, outside, and side-by-side growth of silicon versus silica on zeolite.

It was demonstrated that zeolite can be used as a pseudo-template to grow very fine and uniform silicon nanostructures via disproportionation reaction of SiO by thermal evaporation. Three distinct types of composite nanowires and nanotubes of silicon and silica were grown on the surfaces of zeolite Y pellets. The first type is formed by an ultrafine crystalline silicon nanowire sheathed by an amorphous silica tube (a silicon nanowire inside a silica nanotube). The second type is formed by a crystalline silicon nanotube filled with amorphous silica (a silicon nanotube outside a silica nanowire). The third type is a biaxial silicon-silica nanowire structure with side-by-side growth of crystalline silicon and amorphous silica. These silicon nanostructures exhibit unusually intense photoluminescence (in comparison to ordinary silicon nanowires).

Journal Article↗
PubMed1996

Serum silicon levels are elevated in women with silicone gel implants.

The metabolic fate of silicone gel leaked into the body from an implant is unknown. In this study, serum from 72 women with silicone gel breast implants and 55 control women was blindly assayed by inductively coupled plasma atomic emission spectroscopy (ICP-AES) for elemental silicon. Samples were processed using materials free of silicon. The mean silicon level in controls was 0.13 +/- 0.07 mg/l (range 0.06-0.35 mg/l), while in implant patients, the mean was significantly higher at 0.28 +/- 0.22 mg/l (range 0.06-0.87 mg/l) (P < 0.01, Student's t-test with correction for unequal variances). Using the mean of the control group + 2 SD as a cutoff for normal range (0.27 mg/l), 25/72 (34.7%) implant patients exceeded this value, compared with 2/55 (3.6%) controls. There was no significant correlation between past rupture of one or both implants, current rupture at the time of the blood draw or the number of years with implants and silicon levels. The results suggest that elevations of serum silicon are seen in many women with silicone gel breast implants. The kinetics of this elevation and the actual chemical species of the measured silicon remain to be determined.

Adult↗
PubMed2003

Determination of siloxanes, silicon, and platinum in tissues of women with silicone gel-filled implants.

Silicone [poly(dimethylsiloxane)] gel used in breast implants has been known to migrate through intact silicone elastomer shells, resulting in the clinically observable "gel bleed" on the implant surface. Although silicon concentrations in capsular tissues of women with silicone prostheses have been measured with element-specific silicon analyses, no silicone-specific investigation of these tissues has been performed as yet.A combination of element-specific inductively coupled plasma high-resolution isotope dilution mass spectrometry (ICP-HR-IDMS) and species-specific gas chromatography coupled mass spectrometry (GC-MS) was used to analyze silicon, platinum, and siloxanes in prosthesis capsule, muscle, and fat tissues of women (n=3) who had silicone gel-filled breast implants and in breast tissue of non-augmented women (n=3) as controls.In all tissues of augmented women, siloxanes, in particular octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5), and dodecamethylcyclohexasiloxane (D6) were identified. Depending on the siloxane species and type of tissue analyzed, siloxane levels in the range of about 10-1,400 ng g(-1) were detected; total silicon was found in all tissue samples in the range of about 8,900-85,000 ng g(-1). Higher platinum levels ranging from 25-90 ng g(-1 )were detected in fibrin layer and fat tissue of two patients with prostheses. No siloxanes were detected in control breast tissue samples. This investigation of human tissues by a combination of element-specific and species-specific analytical techniques clearly demonstrates for the first time that platinum and siloxanes leak from prostheses and accumulate in their surrounding tissues.

Adipose Tissue↗
PubMed1996

Condensation of silicone oil on the posterior surface of a silicone intraocular lens during vitrectomy.

PURPOSE: We experienced a complication caused by the condensation of silicone oil on the surface of a silicone intraocular lens during pars plana vitrectomy. METHODS: A 74-year-old woman with proliferative vitreoretinopathy underwent a pars plana vitrectomy in her left eye, which contained silicone oil and a silicone intraocular lens. RESULTS: Intraoperatively, condensation of silicone oil on the posterior surface of a silicone intraocular lens caused a loss of visibility during fluid/gas exchange. The silicone oil droplets could not be removed. CONCLUSION: Surgeons should avoid direct contact of silicone oil with silicone intraocular lens.

Aged↗
PubMed1995

Assessment of viability and proliferation of in vivo silicone-primed lymphocytes after in vitro re-exposure to silicone.

The functional response of peripheral blood lymphocytes isolated from 22 patients with silicone gel-filled breast implants was assessed after in vitro re-exposure to silicone. Using cell culture test methods to quantify proliferation and viability and/or activation of lymphocyte microcultures, i.e., the uptake of tritiated thymidine (3H-TdR uptake test) and the reduction of formazan salts (MTT assay), interesting data were obtained. Peripheral blood lymphocytes purified from patients wearing silicone gel-filled breast implants react in vitro to silicone showing a statistically significant increase of both proliferation and viability, while healthy subjects do not respond on in vitro exposure to silicone. Differences resulted even more statistically significant when patients were divided into two groups depending on the type of surgery they underwent: patients with breast augmentation for aesthetic reasons seem to have an increased responsiveness in vitro to silicone compared to patients who experienced a reconstructive surgery of the breast. Although they are still preliminary, being referred to a limited population, these results suggest that the lymphocytes of patients with silicone gel-filled breast implants could be sensitized in vivo toward silicone; the re-exposure of these cells to silicone leads to a higher functional response which could be looked for by using quantitative in vitro test methods.

Adult↗
PubMed1999

A new way of removing silicone oil from the surface of silicone intraocular lenses.

PURPOSE: This study was performed to ascertain the efficacy of Perfluorhexyl-octan, C14F13H17 (F6H8), in dissolving silicone oil from the surface of silicone intraocular lenses. So far F6H8 is the only solvent of silicone oil that is tolerated by intraocular tissues. MATERIALS AND METHODS: Intraocular silicone lenses (Domilens) were examined after application of small droplets of silicone oil of two different viscosities (AdatoSIL-OL 1000 and 5000) followed by rinsing with F6H8. To allow distinction between silicone oil and F6H8 the silicone oil was stained. Microscopic examination was carried out under video control. RESULTS: One hundred microliters of AdatoSIL-OL 1000 could be easily removed with about 800 microl of F6H8; 50 microl of AdatoSIL-OL 5000 also disappeared after 800 microl of F6H8. A larger drop of the latter oil could not be removed even after application of 2 ml of F6H8. CONCLUSION: Silicone oil 1000 can be easily dissolved by F6H8, whereas silicone oil 5000 is more difficult to remove because of its higher viscosity.

Equipment Contamination↗
PubMed1996

Silicone deposition in reconstruction scars of women with silicone breast implants.

BACKGROUND: The possible association of silicone breast implants and disease is a subject of continuous debate and concern. OBJECTIVE: Our purpose was to examine microscopically and ultrastructurally the periprosthetic fibrous capsules and reconstruction scars of women with silicone breast implants. METHODS: Representative samples from the periprosthetic capsules and reconstruction scars from six women with silicone breast implants were examined by a variety of light microscopy techniques, transmission electron microscopy, and electron probe microanalysis. RESULTS: Silicone globules of various sizes were identified in every periprosthetic capsule and reconstruction scar. CONCLUSION: Extrusion and seeding of the incision tract during surgery most likely accounts for the presence of silicone in the reconstruction scar specimens. This observation suggests that the identification of silicone in the reconstruction scars of women with silicone breast implants does not necessarily implicate rupture of the silicone breast implant with systemic dissemination of silicone gel.

Breast Implants↗
PubMed2000

Analysis of silicon in human tissues with special reference to silicone breast implants.

The increase, in the last two decades, in the application of silicones (polysiloxanes) and inorganic silicon compounds in medicine and the food industry, has exposed the human body to extensive contacts with these substances. Most silicone breast implants contain a gel consisting of a crosslinked silicone elastomer swollen by silicone oil (PDMS). Diffusion of PDMS through the silicone elastomer envelope and rupture of the envelope with release of the gel contents both occur clinically. The amount and distribution of silicone compounds in various tissues are key issues in the assessment of health problems connected with silicone implants. We have measured by GFAAS the Si content of tissues from normal and implant patients and the organic solvent extractable Si levels (assumed to be silicone), using careful control of sample collection and preparation. Whole blood levels were: implant patients mean 38.8 (SD 25.6) (microg/kg), controls mean 24.2 (SD 26.7) (microg/kg) in one study and subsequently 103.8 (SD 112.1) and 74.3 (SD 86.5) (microg/kg) in another study. Capsular tissue levels were: gel implants 25047 (SD 39313) (mg/kg of dry tissue), saline implants 20.0 (SD 27.3) (mg/kg of dry tissue) and controls 0.24 (SD 0.39) (mg/kg of dry tissue). Breast milk levels were: implant patients mean 58.7 (SD 33.8) (microg/kg), controls mean 51.1 (SD 31.0) (microg/kg); infant formula mean was 4.40 (mg/kg). Various precautions were undertaken to avoid Si contamination in this work, the most important being a) the use of a Class 100 laboratory for sample preparation and b) application of strict and elaborate washing procedure for specimen collection tools and laboratory plasticware. This data demonstrated that to properly interpret the importance of these numbers for human health, a larger study of "normal" levels of Si in human tissues should be undertaken and factors such as diet, water, race and geographical location should be considered.

Breast Implants↗
PubMed1954

Silicon metabolism in diatoms. I. Evidence for the role of reduced sulfur compounds in silicon utilization.

1. Cells of the fresh water diatom Navicula pelliculosa may be grown in a mineral medium containing a low concentration of silicon. When transferred to a fresh silicate solution and incubated under non-growing conditions such deficient cells rapidly take up silicon from the medium. 2. The utilization of silicon is an aerobic process. 3. When deficient cells are washed with distilled water or saline, their ability to utilize silicon is impaired whereas respiration is unaffected. 4. The ability of washed cells to take up silicon can be partially restored with sulfate or ascorbic acid, and is completely restored by Na(2)S, Na(2)S(2)O(3), glutathione, l-cysteine, dl-methionine, or ascorbic acid plus sulfate. 5. The sulfhydryl reagent, CdCl(2), inhibits silicon utilization of unwashed cells at concentrations which do not affect respiration. This inhibition similarly is reversed by glutathione or cysteine. 6. However, sodium iodoacetate or sodium arsenite inhibits respiration and silicon utilization at the same concentrations. 7. The silicon taken up by deficient cells is deposited at the cell surface as a thickening of the existing silica frustules. 8. Sulfhydryl groups in the cell membrane may be involved in silicon uptake by diatoms.

Cell Membrane↗
PubMed2003

Silicone oil-RMN3 mixture ("heavy silicone oil") as internal tamponade for complicated retinal detachment.

PURPOSE: To evaluate the efficacy and safety of a silicone oil-RMN3 mixture ("heavy silicone oil") as heavier as water internal retinal tamponade after vitrectomy for complicated retinal detachment. The relative density of the heavier-than-water silicone oil was 1.03 g/cm3, and the viscosity was 3,800 cSt. Heavy silicone oil is designed to tamponade the inferior retina in complicated retinal detachment. METHODS: Patients with a complicated retinal detachment involving the inferior part of the retina requiring internal tamponade with silicone oil were recruited for this prospective study. Inclusion criteria were retinal detachment secondary to proliferative vitreoretinopathy (stage > or = C2), inferior or posterior tears, or penetrating trauma. The heavy silicone oil was injected at the end of surgery after peeling of retinal membranes or retinotomy. Follow-up examinations were scheduled at 1, 3, 6 months, and 1 year after the initial surgery. RESULTS: A total of 33 eyes of 33 patients aged from 20 to 84 years (mean, 56 +/- 18 years) were treated with heavy silicone oil. Follow-up ranged from 12 to 16 months. Rhegmatogenous retinal detachment with significant proliferative vitreoretinopathy accounted for 17 cases, inferior holes for three, and trauma with retinal detachment for three. Initial visual acuity ranged from 20/50 to hand motions. Initial retinal reattachment was achieved in all cases. Complications included increased intraocular pressure in six eyes (18%), intraocular inflammation and synechia formation in one eye (3%), a central retinal artery occlusion after heavy oil removal in one eye, and scattered retinal hemorrhages during follow-up in two eyes (6%). Significant emulsification was not observed during intraocular tamponade with heavy silicone oil. At the last follow-up, all eyes had macular attachment, and 24 eyes had a visual acuity better than or equal to 20/400. CONCLUSIONS: The results of this prospective study show the good intraocular tolerance of heavy silicone oil as tamponade in complicated retinal detachment. Its specific gravity allows for sufficient tamponade of inferior retinal tears for at least 3 months without significant side effects.

Adult↗
PubMedDate not supplied

The fate of silicone oil during heat-curing glass siliconization--changes in molecular parameters analyzed by size exclusion and high temperature gas chromatography.

The siliconization of pharmaceutical glass containers, usually for parenteral formulations, is performed in a so-called heat-curing process using diluted aqueous emulsions of medical grade silicone oils. To do this, the emulsion film is spread on the inner container surface, followed by an application of dry heat at temperatures above 300 degrees C. Water and surfactants are removed by degradation and vaporization, while the thermostable poly(dimethylsiloxane) (PDMS) is left on the surface. In the present study, heat-cured siliconized glass containers of two different types were solvent-extracted to obtain material of heat-treated PDMS. These samples were analyzed by size exclusion chromatography (SEC) and high-temperature gas chromatography (GC) with special respect to low molecular-weight siloxanes (LMWS). By comparison with the untreated starting materials, significant changes in the molecular weight distribution (MWD) of the silicone oil were revealed. Almost all of the LMWS present in untreated materials were not detectable in the heat-cured extract of a 100 cSt. Baysilone silicone oil. Small amounts of PDMS-molecules, with chain lengths of 25 up 45 siloxane units, were traceable. The examination of a second product of higher viscosity yielded unexpected results. The heat-treated extract contained none of the siloxanes that were detected in the starting material. Siloxanes of chain lengths of up to 45 units having molecular weights of over 3000 g/mol could not be found after the siliconization process. This led to the conclusion that not only vaporization effects must be responsible for their absence, but also that silicone suffers from a heat-induced degradation. The results of SEC and GC analysis were supported by each other. The whole molecular weight distribution and four distinct fractions were characterized by SEC, while the GC analysis was capable of a high-resolution view into the LMWS fraction below 3500 g/mol. In conclusion, the benefit of the heat treatment is that no LMWS, a source of toxicological concern, remain in the respective containers. On the other hand, an increase in molecular weight and viscosity of the silicone oil, and thus a possible change of the lubricating properties, is likely to happen through removal of LMWS. But these changes probably have no impact on the hydrophobic surface behavior of silicone-treated glass.

Chromatography, Gas↗
PubMed1994

Silicone-specific blood lymphocyte response in women with silicone breast implants.

A blinded cross-sectional study was carried out with 99 women, 44 of whom had silicone breast implants. Group I consisted of 55 healthy volunteer women without breast implants; group II comprised 13 volunteer women with breast implants or explants who felt healthy; group III comprised 21 volunteer women with breast implants who had chronic fatigue, musculoskeletal symptoms, and skin disorders; and group IV comprised 10 women who had their prostheses explanted but still presented with clinical symptoms similar to those of the women in group III. Proliferative responses of peripheral blood mononuclear cells from all 99 women were measured by [3H]thymidine uptake after exposure to SiO2 silicon, or silicone gel. The levels of proliferative responses were expressed as stimulation indices, which were obtained by dividing the counts per minute of stimulated cells by the counts per minute of unstimulated cells. Abnormal responses to SiO2, silicon, or silicone gel were defined as a stimulation index of > 2.8, > 2.1, or > 2.4, respectively. Abnormal responses were observed in 0% of group I, 15% of group II, 29% of group III, and 30% of group IV (P < 0.0005 for group I versus groups II and IV). Thirty-one percent of symptomatic women with silicone gel breast implants had elevated serum silicon levels ( > 0.18 mg/liter); however, there was no significant correlation between abnormal cellular responses and silicon levels in blood serum, type of implant, time since first implantation, prosthesis explantation, number of implants, or report of implant leakage or rupture.(ABSTRACT TRUNCATED AT 250 WORDS)

Breast Implants↗
PubMed2006

Planar tetracoordinated silicon in silicon carbonyl complexes: a DFT approach.

Recently, some works have focused attention on the reactivity of the silicon atom with closed-shell molecules. With CO, silicon may form a few relatively stable compounds, i.e., Si(CO), Si(CO)(2), and Si[C(2)O(2)], while the existence of polycarbonyl (n > 2) silicon complexes has been rejected by current literature. In this paper, the reaction of silicon with carbonyl has been reinvestigated by density functional calculations. It has been found that the tetracoordinated planar Si(CO)(4) complex is thermodynamically stable. In Si(CO), silicon carbonyl, and Si(CO)(2), silicon dicarbonyl, the CO moieties are datively bonded to Si, and Si[C(2)O(2)], c-silicodiketone, is similar to the compounds formed by silicon and ethylene; Si(CO)(4), silicon tetracarbonyl, may be viewed as a resonance between the extreme configurations (CO)(2)Si + 2CO and 2CO + Si(CO)(2). A detailed orbital analysis has shown that the Si bonding with four CO is consistent with the use of sp(2)d-hybridized orbitals on silicon, giving rise to a planar structure about Si.

Journal Article↗
PubMed1996

Intraocular silicone lenses in silicone oil: an experimental study.

BACKGROUND: To evaluate a potential effect of silicone oil on flexible silicone intraocular lenses, four lenses (STAAR AA-4203) were stored in silicone oil under sterile conditions for periods between 1 month and 3 years. METHOD: The edge and surface of the lenses were examined by scanning electron micrography and the findings compared with a lens of the same model which had been stored in Ringer's solution for 2 years. RESULTS: After 1 year of silicone oil exposure, droplets of different sizes adherent to the surface of the lens were found. These changes proceeded to a wave-like appearance of the surface after 2 and 3 years of storage, so that a continuous layer of silicone oil polymers is probably covering the intraocular lens. CONCLUSION: Optical interference has to be considered a possibility if it turns out that the droplets cannot be removed during silicone oil evacuation. Consequently silicone intraocular lenses without hydrophilic preparation of the surface should not be implanted in eyes undergoing combined anterior and posterior segment surgery with silicone oil tamponade or in eyes with high risk for vitreoretinal complications.

Lenses, Intraocular↗