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PubMed1995

Injected liquid silicone, chronic mastitis, and undetected breast cancer.

Although the use of injected liquid silicone for breast augmentation has all but ceased since its widespread use in the 1960s, patients with injected silicone are still seen with a multitude of symptoms. Silicone mastitis is a well-documented phenomenon; however, there has been a paucity of information regarding cancer detection in this group of patients. We report 2 patients who presented with chronic mastitis but on further workup were found to have breast cancer. In both patients, early cancer detection was adversely affected by the presence of free liquid silicone. In view of this and other similar case reports, we advise that simple mastectomy be recommended to those patients with breasts inspissated with liquid silicone who not only have suspicious masses but present with recurrent mastitis or a family history of breast cancer.

Adenocarcinoma↗

PubMed2002

Epidemiology of silicone-gel breast implants.

Silicone breast implants have been marketed in the United States since 1963. Questions remain unanswered on the safety of these medical devices despite their popularity and availability. In 1992, the Food and Drug Administration restricted the availability of silicone-gel breast implants to women requiring them for reconstruction after breast cancer or for other medical indications. Inflatable saline breast implants have remained available for either reconstruction or for cosmetic augmentation while manufacturers completed studies addressing issues of safety and effectiveness. The Food and Drug Administration (FDA) has less concern today regarding a putative association between breast implants and autoimmune disease because of epidemiologic studies that have indicated that there is not a large increase in risk for connective tissue disease in women with breast implants. These studies have not ruled out a small increase in risk of connective tissue disease to these women nor have they addressed the issue of an atypical syndrome related to silicone. The FDA has continuing concerns over local complications that are related to breast implants. The current review provides a brief discussion of the regulatory history of silicone implants and of FDA concerns over breast implants, implant prevalence, studies of systemic and local complications related to breast implants, and a brief description of the FDA study of silicone-gel breast implant rupture.

Autoimmune Diseases↗

PubMed2000

Probing and bicanalicular silicone tube intubation under nasal endoscopy in congenital nasolacrimal duct obstruction.

PURPOSE: To evaluate the beneficial effects of nasal endoscopy on preventing complications during probing and bicanalicular silicone intubation, and to determine the structural nasal abnormalities in congenital nasolacrimal duct obstruction. METHODS: Probing and silicone tube intubation under nasal endoscopy were performed in 37 eyes of 26 patients who ranged in age from 7 to 60 months (mean, 18.8 +/- 13.4 months). RESULTS: By nasal endoscopy, the inferior turbinate and meatus appeared normal in 15 patients (58%), whereas 11 patients (42%) had hypertrophy of the inferior turbinate and/or stricture in the inferior meatus. Twenty-four of 26 eyes (92%) were cured by probing only. We performed silicone tube intubation and cured 11 of 12 eyes (92%) including two failures. Of 14 eyes that had undergone failed probings elsewhere, the success rate was 92.8% (13 of 14 eyes). The overall success rate of probing and silicone tube intubation under nasal endoscopy was 97%. CONCLUSION: Nasal endoscopy during probing and bicanalicular silicone tube intubation is useful especially in selected cases of failed probings. Nasal endoscopy should assist the inexperienced surgeon in preventing trauma to the nasal base and septal mucosa, hemorrhage, and passage of the probe under the mucosa rather than through the ostium.

Child, Preschool↗

PubMed2003

Effects of lacrimal occlusion with collagen and silicone plugs on patients with conjunctivitis associated with dry eye.

PURPOSE: To determine whether canalicular occlusion with collagen and silicone plugs reduces the severity of symptoms in patients with conjunctivitis secondary to dry eye. METHODS: This was a prospective, randomized, double-masked study conducted at a single center in Mexico, in which 61 patients with dry eye/conjunctivitis were assigned to progressive lacrimal occlusion with collagen and silicone plugs or a sham procedural group. Outcome variables included total and individual dry eye and conjunctivitis symptom scores, moisturizing agent usage, best-corrected visual acuity, ocular comfort level, visual performance, corneal/conjunctival fluorescein staining, and incidence of adverse events. RESULTS: Total dry eye and conjunctival symptom scores were reduced by 43.7 and 33.7%, respectively 2 weeks after occlusion of all four lacrimal canaliculi with collagen plugs, increasing to 77.4 and 72.1% 2 weeks later following superior canalicular occlusion of both eyes with silicone plugs and inferior placement of collagen plugs. At the 8-week visit (4 weeks after silicone plug implantation of the inferior canaliculi of both eyes), the reduction in total dry eye and conjunctival symptom scores further increased to 94.2 and 93.0%, respectively, accompanied by a marked decline in each of the seven individual symptom scores (dryness, watery eyes, itching, burning, foreign body, fluctuating vision, and light sensitivity). In concert with these changes, moisturizing agent usage and corneal/conjunctival fluorescein staining decreased in a progressive fashion over the 8-week study period, and best-corrected visual acuity, ocular comfort, and visual performance improved in the absence of any treatment-related adverse events except for one case of epiphora. The response of patients to lacrimal occlusion can be sharply contrasted with the sham procedure group, which remained relatively unchanged from baseline at each of the study visits. CONCLUSIONS: Progressive lacrimal occlusion with collagen and silicone plugs was of clinical benefit to patients with dry eye and conjunctivitis.

Adult↗

PubMed1999

Colored silicone injection for use in neurosurgical dissections: anatomic technical note.

OBJECTIVE: The dissection of cadaveric specimens is very important for a more sophisticated understanding of neurosurgical anatomic features and approaches. Teaching known approaches to residents or learning new approaches is best performed in a cadaveric laboratory. The utility of neurosurgical cadaveric dissections can be improved by injecting the intracranial vascular tree with colored silicone. The vascular anatomic features, which are integral to neurosurgical procedures, are much more clearly defined in injected specimens. METHODS: Self-curing colored silicone rubber is used to inject the arteries and veins (red and blue, respectively) of the head. This process is described in a step-by-step format. Six steps are required and can be summarized as follows: 1) exposure of the great vessels, 2) cannulation of the great vessels, 3) irrigation of the head, 4) preparation of the colored silicone, 5) injection of the colored silicone, and 6) evaluation of the final specimen. CONCLUSION: Injection of colored silicone into the vascular tree can enhance the educational value of cadaveric head dissections. This report describes the technique of vascular injection that is used in the Goodyear Microsurgical Laboratory, the University of Cincinnati, and the Mayfield Clinic.

Brain↗

PubMed1994

Health risks of failed silicone gel breast implants: a 30-year clinical experience.

The purpose of this paper is an assessment of clinically evident systemic health problems associated with failed silicone gel breast implants. A computer search of the medical records of 2033 patients receiving implants in the years 1962-1992 revealed that between 1970 and 1992, 200 women 14 to 75 years of age underwent secondary silicone gel breast implant procedures by a single surgeon. This allowed determination of the exact integrity status of 681 implants collectively placed in these 200 patients between 1962 and 1992 and followed clinically for a median of 49 months. The common indications for surgical reexploration in these 200 patients were capsulectomy, open capsulotomy, or implant exchange/removal. All patients had a minimum clinical follow-up of 6 months. Surgical findings revealed that 577 (85 percent) implants were intact in 135 (67.5 percent) patients and that in 65 (32.5 percent) patients, 104 (15 percent) implant failures were found. The patients' medical records were reviewed with specific attention to diagnoses suggesting immune-related disorders, siliconoma, acquired non-breast malignancies, metachronous breast cancer, and recurrent breast carcinomas. In this very select subgroup of 65 patients with silicone gel breast implants which had failed or were deteriorating, no excess of expected immune-related disorders or malignancies was identified. Our 30-year clinical experience with silicone gel breast implants for augmentation mammaplasty or breast reconstruction failed to demonstrate that clinically evident adverse health problems are incurred by those women who subsequently experience a silicone gel breast implant failure.

Adolescent↗

PubMed1996

Factors contributing to patient satisfaction with breast reconstruction using silicone gel implants.

Recently, concerns have been raised about risks and benefits of silicone gel implants for breast reconstruction. Using a survey conducted during the silicone controversy that began in 1990, this study examines patient satisfaction in 174 women with silicone breast implants. Overall satisfaction was high; 43 percent indicated complete satisfaction, and only 3 percent stated they were "not at all" satisfied. Satisfaction was correlated with each woman's assessment of how reconstruction met her expectations, particularly expectations about clothes fitting better, feeling whole, looking normal, and having similar-appearing breasts. Higher levels of satisfaction also were associated with lower body mass index and absence of medical problems. While patients appeared satisfied with their reconstructions, 34 percent said they would be completely unlikely to choose silicone implants today. Further research is needed to understand the impact of the silicone breast implant debate on women who have had or may consider breast reconstruction.

Adult↗

PubMed1998

Silicone in nasal augmentation rhinoplasty: a decade of clinical experience.

A number of materials, both biologic and alloplastic, have been used for nasal augmentation. Although biologic bone and cartilage grafts are associated with lower infection rates, they are also associated with long-term resorption and donor-site morbidity. Alloplastic materials, in particular silicone, have been associated in the literature with extrusion and infection but have the advantages of being affordable and easy to reshape with no requirement for harvesting autografts. A 10-year experience with silicone nasal augmentation documenting clinical experience, acute and long-term complications, and patient satisfaction was reviewed. All patients undergoing silicone augmentation rhinoplasty between July of 1985 and December of 1995 were reviewed. Preoperative nasal phenotype, operative data, and postoperative outcome were recorded. Long-term follow-up was undertaken using a telephone survey. There were 422 patients who underwent silicone nasal augmentation from July of 1985 to December of 1995. Only nine were men. The indications were for aesthetic nasal augmentation in 98 percent, and the majority (98 percent) were of South East Asian origin. Mean age was 26 (range 17 to 36), and 41 of the 422 patients had had previous nasal augmentation performed before presentation. Twenty-three patients (5.5 percent) had complications requiring removal of the implant within 30 days of surgery. These included displacement, prominence, hemorrhage, and excessive pressure in addition to obvious supratip deformity. On late follow-up, a further 18 patients (4.3 percent) had subsequent removal of the prosthesis. The most common reason for this was either displacement or over-prominence, more often judged by the surgeon than the patient. There were only two patients (0.5 percent) who had extrusion of the prosthesis. A total of 266 patients (63 percent) were contacted for a telephone interview. The majority of patients (84.2 percent) were satisfied with their nasal shape. Of the 42 patients (15.8 percent) who were not satisfied, 21 patients still wanted further augmentation of their nose. Photographic analysis of 198 patients showed a mean augmentation of 16.5 percent (range 4.0 to 27.5). Amount of augmentation correlated with preoperative nasal phenotype. Silicone nasal augmentation is a safe and effective procedure when used for moderate increases in nasal height. Contrary to previous reports, this series showed no associated infection. If the implant is shaped appropriately to the patient's nasal phenotype, the risk of extrusion may be reduced.

Adolescent↗

PubMed1993

Silicone oil as a delivery vehicle for BCNU in rabbit proliferative vitreoretinopathy.

The antiproliferative properties of a single intravitreous injection of BCNU [carmustine; 1,3-bis(2 chloroethyl)-1-nitrosourea] dissolved in 1 ml of medical grade, 1,000-centistoke silicone oil were evaluated in a rabbit model of proliferative vitreoretinopathy (PVR). 10 micrograms and 15 micrograms of BCNU in 1 ml silicone oil resulted in a 46% and 27% reduction in the incidence of retinal detachments, respectively. Chi-square tests showed a significant statistical difference (P < 0.05) between the control and treated groups. However, histopathologic examination of the eyes injected with BCNU and silicone oil indicated some retinal disorganization even at the lower therapeutic levels. With a therapeutic index of < 1.0, BCNU in silicone oil has a low margin of safety for treatment of PVR. Nevertheless, this study demonstrates that silicone oil when used for retinal tamponade in PVR may be the vehicle for delivery of a lipophilic antiproliferative agent.

Animals↗

PubMed1997

Management of endophthalmitis in a silicone oil-filled eye.

PURPOSE: To describe the management of endophthalmitis in an eye filled with silicone oil for prolonged internal retinal tamponade. METHODS: A patient with a silicone oil-filled eye developed endophthalmitis postoperatively. Results of clinical examination, diagnostic procedures, and surgical management are described. RESULTS: Removal of the silicone oil, injection of antibiotics into the fluid-filled vitreous cavity, and reinjection of silicone oil resulted in resolution of the endophthalmitis and improvement in vision. CONCLUSIONS: Aggressive management of endophthalmitis in an eye requiring silicone oil tamponade may salvage useful vision.

Anti-Bacterial Agents↗

PubMed1997

Severe ocular trauma managed with primary pars plana vitrectomy and silicone oil.

PURPOSE: This study evaluated the outcome of severely injured eyes treated with early primary vitrectomy with silicone oil filling. METHODS: A total of 435 eye injuries, which required surgical intervention, were reviewed retrospectively. In 13 eyes (3%) pars plana vitrectomy and silicone oil filling were performed as primary surgical repair. Silicone oil filling was restricted to cases with laceration of the retina larger than 4 disc diameters (nine eyes), primary retinal detachment larger than two quadrants (two eyes) and/or persistent intrasurgical hemorrhage (12 eyes). All patients underwent surgery within 24 hours. RESULTS: After a mean follow-up period of 28.7 months (range, 9-70 months), 11 eyes achieved a visual acuity ranging from 20/25 to 20/200. Silicone oil was removed in 11 of 13 eyes after 5.8 +/- 4.6 months. Recurrent proliferative vitreoretinopathy developed in two eyes. CONCLUSIONS: Silicone oil tamponade after early primary pars plana vitrectomy may be an alternative for primary repair after trauma, especially in severely injured eyes with retinal lacerations larger than 4 disc diameters, persistent intrasurgical bleeding, and/or primary retinal detachments.

Adolescent↗

PubMed1997

Effect of head position on refraction in aphakic and phakic silicone-filled eyes.

BACKGROUND: The refraction of the eye is altered significantly after the instillation of silicone oil into the vitreous cavity because of the silicone oil's high refractive index. The degree of the refractive change shows diurnal variation and depends on the patient's head position. PATIENTS AND METHODS: To analyze the degree and time course of refractive changes with respect to head position, the authors performed objective refraction in five aphakic and five phakic silicone oil-instilled eyes with attached maculae using an automatic hand-held refractometer. In each patient, 25 measurements were taken at short intervals using a hand-held autorefractometer with the patient in different positions (supine, head tilted down, and primary eye position). RESULTS: The highest shift of refraction was +5.95 +/- 2.63 diopters spherical equivalent in aphakic eyes and +2.45 +/- 0.71 diopters in the phakic eyes after the patient's position was changed from supine to head tilted down. Three minutes after the position change the refractive shift was stable in almost all eyes. Only slight changes in cylinder and the respective corresponding axis with a mean cylinder shift of 10.1 +/- 5.1 degrees were noted. CONCLUSIONS: Immediately after the head position was changed, aphakic eyes demonstrated more pronounced refractive shifts than phakic eyes. The results of this study explain patients' reports of diurnal changes in visual acuity after intraocular silicone oil instillation. Refractive changes caused by silicone oil stabilized a few minutes after a change in head position.

Aphakia, Postcataract↗

PubMed2000

Efficacy of the ganciclovir implant in the setting of silicone oil vitreous substitute.

OBJECTIVE: To evaluate the efficacy of the ganciclovir implant in the setting of silicone oil vitreous substitute. MATERIALS AND METHODS: The authors retrospectively reviewed the charts of 19 patients with cytomegalovirus retinitis who had both a ganciclovir implant and silicone oil vitreous substitute. None of the patients was receiving highly active antiretroviral therapy during the study period. Kaplan-Meier analysis was used to evaluate time to progression in eyes with the ganciclovir implant and silicone oil. RESULTS: In all eyes, the ganciclovir device implantation preceded or coincided with silicone injection. Kaplan-Meier analysis revealed that time to 25% failure from the date of the presence of both the implant and oil was 129 days. Time to 25% failure from the date of ganciclovir device implantation was 179 days. CONCLUSIONS: These results compare favorably with conventional treatment. The ganciclovir implant can be a useful treatment modality in eyes with silicone oil.

Antiviral Agents↗

PubMed2001

Results and complications of temporary silicone oil tamponade in patients with complicated retinal detachments.

BACKGROUND: To assess the results and complications of temporary silicone oil tamponade in the treatment of complicated retinal detachments. METHODS: Fifty-eight consecutive eyes undergoing silicone oil removal were studied in a retrospective fashion. Forty-two eyes with proliferative vitreoretinopathy, nine eyes with giant tears, and seven traumatized eyes were included. In addition to anatomic and visual results, the following complications and their associated preoperative and intraoperative variables were assessed: glaucoma, hypotony, and keratopathy. RESULTS: Anatomic success was achieved in 81% of the eyes. Postoperative glaucoma was found in 12%, hypotony in 9%, and keratopathy in 7% of the eyes. Twenty-six (45%) of the 58 eyes had an increase in visual acuity of at least two Snellen lines after silicone oil removal. After multivariate logistic regression analysis for all variables versus the visual and anatomic results and versus the complications of glaucoma, hypotony, and keratopathy successively, a total of three or more operations (P < 0.05; odds ratio, 14.7) and the absence of an encircling band (P < 0.05; odds ratio, 29.9) were associated with redetachment, and a retinectomy size of more than 180 degrees was associated with hypotonia (P < 0.05; odds ratio, 67.5). CONCLUSIONS: Temporary silicone oil tamponade may be associated with a lower incidence of complications than recent studies have reported. Despite the acceptable risk of recurrent retinal detachment, the early removal of silicone oil may yield a lower rate of anterior segment complications and an increase in visual acuity in approximately half the eyes.

Adolescent↗

PubMed2003

Cataract surgery and silicone oil removal: visual outcome and complications in a combined vs. two step surgical approach.

PURPOSE: To compare visual outcome and complications of two surgical strategies for patients who needed cataract surgery and silicone oil removal. METHODS: A prospective, nonrandomized study was performed to compare two groups of patients who had cataract surgery and silicone oil removal from April 1998 to January 2002. From April 1998 to November 1999, patients had two surgical sessions with cataract surgery before silicone oil removal (Group 1), and from December 1999 to January 2002, patients underwent combined cataract surgery and silicone oil removal in a single session (Group 2). RESULTS: Thirty-five patients were included in each group. The postoperative visual acuity improved by at least two lines of Snellen in 13 patients (37.1%) in Group 1 and 15 (42.8%) patients in Group 2 (P=0.63). The mean visual improvement was 0.12 lines and 0.13 lines in groups 1 and 2 (P=0.62). Complications in groups 1 and 2 included transient intraocular pressure rise (25.7% versus 28.5%), retinal detachment (14.2% versus 11.4%), fibrin reaction (5.7% in both groups), and persistent intraocular pressure rise (2.8% in both groups). CONCLUSION: The visual outcome and complication rates were similar in both groups. Combined surgery offers the advantages of a single surgical event and a faster visual rehabilitation. We therefore suggest a surgical approach with combined cataract surgery and silicone oil removal in selected patients with a stable retinal situation.

Capsulorhexis↗

PubMed2004

Preparation and processing of vitreoretinal instrumentation and equipment as a risk factor for silicone oil emulsification.

PURPOSE: To investigate possible sources for the induction of silicone oil emulsification in patients' eyes. METHODS: The contaminants on a ready-to-use standard set of vitreoretinal instruments cleaned and sterilized in an eye clinic were determined. The determination of detergents was carried out according to a standardized procedure, which uses ultrapurified water to rinse the equipment in question, followed by a measurement of the conductivity. Silicone oil remnants were determined using Fourier transformed infrared spectroscopy. RESULTS: Ionic components of detergents and remnants of silicone oil could be detected on instrumentation deemed sterile, clean, and ready-to-use. CONCLUSION: During routine cleaning and sterilization of vitreoretinal instruments and accessories, remnants of silicone oil and detergents can persist and trigger emulsification of silicone oil, which came into contact with these contaminated devices during instillation of the endotamponade.

Detergents↗

PubMedDate not supplied

Persistence of indentation with bioabsorbable poly-L/D-lactide versus silicone sponge scleral buckling implants.

PURPOSE: To measure the amount and duration of indentation depth achieved with biodegradable poly-L/D-lactide 96/4 (PLA96) and silicone sponge implants. METHODS: Thirty rabbits underwent a scleral buckling procedure. A PLA96 buckling implant was used in 15 rabbits and a silicone sponge buckling implant was in 15 rabbits. A circumferential scleral buckling implant was sutured episclerally on the left eye of each rabbit, just temporal to the superior rectus muscle and 7 mm posterior to the limbus. Computed tomography was performed at 1 week, 3 months, and 5 months after surgery. RESULTS: The PLA96 buckling implant (implant diameter, 3-3.5 mm) used in this study created lower indentation than the silicone sponge implant (implant diameter, 4 mm). The indentation created by the PLA96 implant decreased over time compared with that created by the silicone implant. There were no complications related to either kind of implant. CONCLUSION: Both the silicone sponge implant and the PLA96 implant caused indentation that decreased in a comparable manner over the follow-up period (5 months).

Absorbable Implants↗

PubMed2005

Incidence and management of elevated intraocular pressure after silicone oil injection.

PURPOSE: To determine the incidence and clinical features of chronic elevated intraocular pressure after pars plana vitrectomy and silicone oil injection for complicated retinal detachments, and to evaluate the clinical management of eyes with secondary glaucoma. METHODS: This was an observational consecutive case series of 450 eyes in 447 patients who were treated with pars plana vitrectomy and silicone oil injection. Patients who developed secondary glaucoma were treated medically with antiglaucoma medications and surgically with glaucoma drainage implants placed in an inferior quadrant. Main outcome measures were intraocular pressure, number of glaucoma medications, surgical success, and complications. RESULTS: Fifty-one of 450 eyes (11%) developed elevated intraocular pressure after pars plana vitrectomy and silicone oil injection whereas 399 eyes (89%) did not have a rise in intraocular pressure. Of the 51 eyes that developed elevated intraocular pressure, 40 (78%) were treated only with glaucoma medicines. Medical therapy reduced the intraocular pressure from a mean +/- SD of 26 +/- 13.4 mm Hg before treatment to 18 +/- 9.1 mm Hg after medical treatment (P = 0.002). The 11 of 51 eyes (22%) with elevated intraocular pressure that failed medical therapy were treated surgically with Ahmed Glaucoma Valve implantation within 12 months of silicone oil injection. In the surgical group, intraocular pressure was reduced from a mean +/- SD of 44 +/- 11.8 mm Hg before surgery to 14 +/- 4.2 mm Hg at the most recent follow-up after surgery (P < 0.001). The number of antiglaucoma medications was reduced from 3.5 +/- 0.7 before surgery to 1.2 +/- 0.5 at the most recent follow-up after surgery (P < 0.001). CONCLUSION: Chronic intraocular pressure elevation occurs in a minority (11%) of patients who are treated with silicone oil. Most of these eyes are effectively treated with antiglaucoma medications. Eyes that do not respond to medical therapy may be effectively managed with glaucoma drainage implant placement in an inferior quadrant.

Adolescent↗