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BACKGROUND: Cystoid macular edema (CME) can develop following silicone oil placement in complex vitreoretinal surgeries, contributing to poor visual outcomes. In this study, we investigated the clinical and surgical characteristics associated with the development of CME following the use of silicone oil (SO) in pars plana vitrectomy (PPV) surgeries. METHODS: We conducted a retrospective chart review of patients who underwent implantation of SO during PPV from 2010 to 2020 by a single surgeon. Patient demographics, type of oil, duration of oil tamponade, retinectomy size, diabetic status, lens status, prior panretinal photocoagulation, visual acuity, and incidence of CME were reviewed. RESULTS: This study included 43 eyes from 40 patients who underwent SO tamponade for retinal detachment (RD) surgery. The mean duration of SO tamponade was 15.7 ± 12.7 months (range: 1-58 months). The most common indication for surgery was diabetic tractional RD (32.7%), followed by traumatic RD (16.3%) and rhegmatogenous RD with proliferative vitreoretinopathy (11.6%). Of the 43 eyes, 18 (41.9%) developed CME for the first time after PPV with SO placement, with 8 (44%) resolving within a year of oil removal. The mean duration for the development of CME was 9 months. A logistic regression model showed that a scleral buckle procedure and poor initial vision were statistically significant factors for predicting the development of CME (ORs: 11.65 and 16.06, respectively). Overall, 91% of the patients had stable or improved vision after surgery. CONCLUSIONS: The use of a scleral buckle procedure and poor initial vision are significant factors for predicting CME following silicone oil tamponade in PPV surgeries, with 41.9% of patients developing CME with an average duration of 9 months. Recognizing such factors can lead to early monitoring and prompt management of CME. MEETING PRESENTATION: Partial analyses were presented at the ASRS 2020 conference. CLINICAL TRIAL NUMBER: Not applicable.

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Purpose: To determine the physiological status of the retina by electroretinography (ERG) using skin electrodes and the RETevalTM system in eyes that had undergone pars plana vitrectomy (PPV) with silicone oil (SO) tamponade. The vitrectomy was performed for a retinal detachment and proliferative diabetic retinopathy (PDR). Design: Retrospective case series. Methods: ERGs were recorded with the RETevalTM system (LKC Technologies Inc. Gaithersburg, MD; Welch Allyn, Inc. Skaneateles Falls, NY) from eight eyes with PDR before and after the SO removal. The amplitudes and implicit times of the a- and b-waves of the ERGs before the SO removal were compared to that after the SO removal. Results: ERGs were recordable in four eyes before and after the SO removal and the a- and b-amplitudes improved in three eyes and worsened in one eye after the SO removal. In the remaining four eyes, ERGs were non-recordable both before and after the SO removal. Conclusion: These results indicate that ERGs picked up by skin electrodes can be used to assess the physiology of the retina in eyes with a SO tamponade. The flat ERGs in the SO-filled eye indicated the presence of diffuse retinal damage which was confirmed by the flat ERGs after the SO removal.

There has been an increasing number of reports on evaluating the retinal function using electroretinography (ERG) with skin electrodes. The main advantage of this system is the ability to record ERGs with a skin electrode that does not touch the cornea and ocular surface. This reduces the risk of infection especially in the postoperative period and in clinical situations where infection is suspected. In addition, there have been only a few reports evaluating the function of the retina by ERG in SO-filled eyes. We recorded ERGs with the RETeval (LKC Technologies Inc. Gaithersburg, MD; Welch Allyn Inc. Skaneateles Falls, NY) device, a relatively new ERG recording system that uses skin electrodes and is less invasive. We recorded ERGs from eight SO-filled eyes with proliferative diabetic retinopathy (PDR). In 4 SO filled eyes, the amplitudes increased in three eyes after the SO removal. In the other four eyes, ERGs were non-recordable before and after the SO removal. These results suggest that the RETeval system that uses skin electrodes can be used to assess the retinal function in PDR eyes with a SO tamponade. We suggest that the absence of ERGs in the SO filled eyes was not due to the electrical non-conductive effects of SO but may indicate the presence of diffuse retinal damage which was confirmed after the SO removal.

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A droplet microfluidic device to capture in real-time protein aggregation at liquid-liquid interfaces is described. In contrast to conventional methods, typically characterized by a lag time between the application of interfacial stress and the measurement of protein aggregation, here protein adsorption, the formation of a viscoelastic protein layer, aggregation, and shedding of protein particles into solution is simultaneously monitored. The device is applied to analyze the stability of antibody formulations over a wide range of concentrations (1-180 mg mL-1) at the silicone oil (SO)-water interface under controlled mechanical deformation. The adsorption onto oil droplets induces the formation of a viscoelastic protein layer on a subsecond timescale, which progressively restricts the relaxation of the droplets within the chip. Upon mechanical rupture, the protein layer releases particles in solution. The rate of particle formation increases strongly with concentration, similar to the bulk viscosity. Concentrations above 120 mg mL-1 lead to aggregation in seconds and drastically decrease the mechanical perturbations required to shed protein particles in solution. These results are important for the development of formulations at high-protein concentrations (>100 mg mL-1) and indicate that particular attention should be given to interface-induced particle formation in this concentration range. In this context, low-volume microfluidic platforms allow the assessment of protein physical instabilities early in development and represent attractive tools to optimize antibody stability and formulation design consuming limited amounts of material.

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Purpose: Unexplained vision loss after silicone oil removal is a well-documented but incompletely understood entity for which there is no effective treatment described in the existing literature. We present a case where intensive oral and periocular steroid treatment resulted in significant subjective and objective clinical improvement. Observations: After successful pars plana vitrectomy with silicone oil endotamponade to repair a macula sparing retinal detachment, the patient's best corrected visual acuity was 20/20 with silicone oil in the operative eye. However, seven weeks after uncomplicated combined silicone oil removal and cataract extraction with intraocular lens insertion, best corrected visual acuity was 20/250 with no new ophthalmic pathology to explain the vision loss. After a four week course of oral prednisone and three periocular triamcinolone injections over a period of nine weeks, visual acuity improved to 20/25 -2 in the operative eye. Serial multifocal electroretinography initially showed severely diminished amplitudes but improved markedly over the course of steroid treatment. Conclusions and Importance: Although no effective treatments are described in the existing literature, improvement in visual acuity, visual field, and electroretinogram in this case suggests that intensive steroid treatment (periocular and systemic) may be efficacious in treating unexplained vision loss after silicone oil removal.

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PURPOSE: To report the rate of retinal redetachment after silicone oil removal following rhegmatogenous retinal detachment surgery and to determine potential risk factors. METHODS: Retrospective observational case series of 161 eyes who underwent rhegmatogenous retinal detachment surgery and subsequent silicone oil removal. Pre- and intraoperative risk factors were evaluated using univariate and multivariate logistic regression. We also evaluated the effect of tamponade duration on anatomical outcomes. RESULTS: The median tamponade duration was 5.9 [4.3;7.6] months. Seventeen (10.6%) eyes underwent silicone oil removal within 3 months of surgery, with a median delay of 2.3 [2.0;2.8] months. The rate of retinal detachment after silicone oil removal was 14.9%. A history of previous unsuccessful surgery was the only significant risk factor for retinal redetachment after silicone oil removal (OR 4.8, 95%CI [1.5;19.0], p = 0.02). The use of 360° laser retinopexy and concomitant air or gas tamponade during silicone oil removal were not found to affect the redetachment rate. Eyes with silicone oil tamponade ≤ 3 months showed an increased, albeit not significant, risk of developing recurrent rhegmatogenous retinal detachment after silicone oil removal (35.3% versus 12.5%, p = 0.06). CONCLUSION: A retinal redetachment occurred in 14.9% of eyes undergoing silicone oil removal following rhegmatogenous retinal detachment surgery. Previous failed surgery was associated with a 4.8-fold increased risk of developing recurrent rhegmatogenous retinal detachment after silicone oil removal. Eyes with silicone oil tamponade ≤ 3 months tended to have a higher redetachment rate. TRIAL REGISTRATION NUMBER: ID NCT05647928 (12th April 2022).

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Purpose: To present the successful application of fibrin glue as a surgical adjunct in the management of complex rhegmatogenous retinal detachment (RRD). Methods: In this retrospective case series, fibrin glue was used as a surgical adjunct in 5 cases of complex RRD. In each case, standard pars plana vitrectomy and laser retinopexy were performed by the same surgeon. Fibrin glue was used intraoperatively as a tamponade to seal the breaks because the isolated use of conventional tamponade agents was not feasible given the variable nature of the complex RRDs, the anatomy of the eye, or an inability to maintain postoperative positioning. Results: In 1 patient previously treated for a large corneoscleral tear, fibrin glue was used to seal a large iatrogenic retinal break caused by a fragmatome-related surge that led to a quadrantic RD. In 2 patients treated for combined RRD, fibrin glue was used with silicone oil to manage recurrent RRD with incompletely drained thick subretinal fluid and blood. In 2 other cases, fibrin glue was applied to manage RRD in congenital aniridia with advanced glaucoma and aphakia. In all cases, retinal attachment without serious adverse effects was attained over a follow-up ranging from 4 to 6 months. Conclusions: Fibrin glue is an effective, safe surgical adjunct in complex RRD. It can be used to transiently seal a retinal break when use of a conventional tamponade agent is not possible or not sufficient alone.

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Anti-VEGF agents, e.g., bevacizumab, are used in retinal surgery, while their interaction with silicone oils and novel hydrogels remains unclear. This study examines the in vitro pharmacokinetics of bevacizumab in silicone oil-filled eyes compared to various hydrogel replacements and the porcine vitreous body as well as its impact on the interface tension of silicone oils. An in vitro model filled with light or heavy silicone oil, porcine vitreous bodies, or hydrogels (alginate and polyethylene glycol (PEG)-based) was equilibrated with a balanced salt solution. Monitoring of bevacizumab in the aqueous phase was conducted for up to 24 h, and its effect on interfacial tension was studied. Significant differences in bevacizumab partitioning were observed across endotamponades after 24 h. In silicone oils, bevacizumab was found exclusively in the aqueous phase, while in the other endotamponades, it accumulated in the gel phase (96.1% in porcine vitreous body, 83.5% in alginate, and 27.6% in PEG-based hydrogel). Bevacizumab significantly reduced interfacial tension (40 to 8 mN/m), possibly enhancing silicone oil emulsification. The type of endotamponade heavily influenced the bevacizumab concentration in the aqueous. The vitreous body and replacement hydrogels likely serve as a drug reservoir, highlighting the need for in vivo studies to explore these interactions prior to clinical application.

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This paper presents the fabrication and characterization of plane capacitors utilizing magnetodielectric materials composed of magnetizable microfibers dispersed within a silicone oil matrix. The microfibers, with a mean diameter of about 0.94 µm, comprise hematite (α-Fe2O3), maghemite (γ-Fe2O3), and magnetite (Fe3O4). This study investigates the electrical behavior of these capacitors under the influence of an external magnetic field superimposed on a medium-frequency alternating electric field, across four distinct volume concentrations of microfibers. Electrical capacitance and resistance measurements were conducted every second over a 60-s interval, revealing significant dependencies on both the quantity of magnetizable phase and the applied magnetic flux density. Furthermore, the temporal stability of the capacitors' characteristics is demonstrated. The obtained data are analyzed to determine the electrical conductance and susceptance of the capacitors, elucidating their sensitivity to variations in microfiber concentration and magnetic field strength. To provide theoretical insight into the observed phenomena, a model based on dipolar approximations is proposed. This model effectively explains the underlying physical mechanisms governing the electrical properties of the capacitors. These findings offer valuable insights into the design and optimization of magnetodielectric-based capacitors for diverse applications in microelectronics and sensor technologies.

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PURPOSE: This study aimed to assess and compare the retinal toxicity associated with silicone oil (SO) and perfluoropropane (C3F8) tamponade following vitreoretinal surgery for fresh rhegmatogenous retinal detachment (RRD), utilizing the office-based Diopsys® NOVA™ system for evaluation. METHODS: Patients who underwent vitreoretinal surgery for fresh RRD and had SO (group 1) or C3F8 (group 2) tamponade were included in a prospective analysis. Flicker full field electroretinography (ffERG) and pattern electroretinography (PERG) tests were performed at 6 months postoperatively. RESULTS: Postoperative best corrected visual acuity (logMAR) was significantly different in group 1 and group 2 patients, 0.48 ± 0.3 and 0.30 ± 0.2, respectively. No significant disparities were found in demographic variables. Flicker ffERG and PERG recordings revealed notable alterations in retinal function parameters in the group 1 compared to the group 2. CONCLUSION: Our findings suggest a correlation between SO tamponade and retinal dysfunction, evidenced by office-based ERG measurements. The Diopsys® NOVA™ protocol offers clinical ease in assessing retinal function. Further controlled studies are essential to validate these findings and guide clinical practice effectively.

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In this study, the loss of quality from the oxidative thermal decomposition of jute fiber was explored during the production of reinforced composite materials. Amino silicone oil was used to modify jute fiber, which was then subjected to thermogravimetric analysis. The modified fiber's thermal decomposition temperature was found to be 271 °C, enhancing the composite's thermal stability. The study also investigated how different jute fiber content affected the mechanical and sound absorption properties of composite materials. Results showed that jute fiber composites had better mechanical properties than pure polypropylene materials, and the average sound absorption coefficient of jute polypropylene composites increased with fiber content. Adding jute fiber to polypropylene effectively improved the sound absorption and noise reduction performance of the material. The average sound absorption coefficient of the composite material at a mass content of 20 wt% was 120 % higher than that of the polypropylene matrix material.

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This paper reviews the latest trends and applications of silicone in ophthalmology, especially related to intraocular lenses (IOLs). Silicone, or siloxane elastomer, as a synthetic polymer, has excellent biocompatibility, high chemical inertness, and hydrophobicity, enabling wide biomedical applications. The physicochemical properties of silicone are reviewed. A review of methods for mechanical and in vivo characterization of IOLs is presented as a prospective research area, since there are only a few available technologies, even though these properties are vital to ensure medical safety and suitability for clinical use, especially if long-term function is considered. IOLs represent permanent implants to replace the natural lens or for correcting vision, with the first commercial foldable lens made of silicone. Biological aspects of posterior capsular opacification have been reviewed, including the effects of the implanted silicone IOL. However, certain issues with silicone IOLs are still challenging and some conditions can prevent its application in all patients. The latest trends in nanotechnology solutions have been reviewed. Surface modifications of silicone IOLs are an efficient approach to further improve biocompatibility or to enable drug-eluting function. Different surface modifications, including coatings, can provide long-term treatments for various medical conditions or medical diagnoses through the incorporation of sensory functions. It is essential that IOL optical characteristics remain unchanged in case of drug incorporation and the application of nanoparticles can enable it. However, clinical trials related to these advanced technologies are still missing, thus preventing their clinical applications at this moment.

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Silicone oil (SO) emulsification is a significant concern in vitreoretinal surgery, leading to various complications. Despite the high prevalence of SO emulsification within the eye, there is currently no standardized method for its early detection. The recent introduction of widefield (WF) imaging and ultra-WF (UWF) imaging with navigated central and peripheral optical coherence tomography (OCT) techniques have shown promising results in providing high-resolution images of the peripheral vitreous, vitreoretinal interface, retina, and choroid. This enhanced visualization capability enables the early identification of emulsified SO droplets, facilitating a proactive therapeutic approach, and mitigating associated adverse events. This comprehensive literature review aims to provide an updated overview of the topic, focusing on the role of WFimaging and UWF imaging and navigated central and peripheral swept-source OCT (SS-OCT) in the early detection and management of SO emulsification. The review discusses the current understanding of SO emulsification, its associated complications, and the limitations of existing detection methods. In addition, it highlights the potential of WF and UWF imaging and peripheral OCT as advanced imaging modalities for improved visualization of SO emulsification. This review serves as a valuable resource for clinicians and researchers, providing insights into the latest advancements in the field of vitreoretinal surgery and the promising role of WF imaging and UWF imaging and navigated central and peripheral SS-OCT in the management of SO.

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Silicone oil (SO) migration into the drug product of combination products for biopharmaceuticals during storage is a common challenge. As the inner barrel surface is depleted of SO the extrusion forces can increase compromising the container functionality. In this context we investigated the impact of different formulations on the increase in gliding forces in a spray-on siliconized pre-filled syringe upon storage at 2-8 °C, 25 °C and 40 °C for up to 6 months. We tested the formulation factors such as surfactant type, pH, and ionic strength in the presence of one monoclonal antibody (mAb) as well as compared three mAbs in one formulation. After 1 month at 40 °C, the extrusion forces were significantly increased due to SO detachment dependent on the fill medium. The storage at 40 °C enhanced the SO migration process but it could also be observed at lower storage temperatures. Regarding the formulation factors the tendency for SO migration was predominantly dependent on the presence and type of surfactant. Interestingly, when varying the mAb molecules, one of the proteins showed a rather stabilizing effect on the SO layer resulting into higher container stability. In contrast to the formulation factors, those different stability outcomes could not be explained by interfacial tension (IFT) measurements at the SO interface. Further characterization of the mAb molecules regarding interfacial rheology and conformational stability were not adequately able to explain the observed difference. Solely a hydrophobicity ranking of the molecules correlated to the stability outcome. Further investigations are needed to clarify the role of the protein in the SO detachment process and to understand the cause for the stabilization. However, the study clearly demonstrated that the protein itself plays a critical role in the SO detachment process and underlined the importance to include verum for container stability.

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Background: Silicone oil is used as endotamponade following vitreoretinal surgery to maintain the retina reattached when indicated. This study investigates the hypothesis that silicone oil causes insulation effects on the retina by affecting its response to light. Methods: Electrophysiological responses to a flash stimulus were recorded using full-field electroretinography (ERG) and visual evoked potentials (VEP). Recordings were performed in 9 patients who underwent surgery for retinal detachment, before (1–2 days) and after (2–3 weeks) silicone oil removal (SOR) in both the study and the control eye. Flash ERG and VEP recordings were performed according to the ISCEV standard protocol. Results: Statistically significant differences were found in the study eye in the amplitudes of the ERG responses and their corresponding ratios, i.e. the amplitude after SOR over the amplitude before SOR, in all conditions tested. No differences were observed in the control eye. The mean ratio of photopic ERG response was 3.4 ± 2.4 for the study and 1.0 ± 0.3 for the control eye (p<0.001). The mean ratio of ERG flicker response was 3.1 ± 2.4 and 1.0 ± 0.3, respectively (p = 0.003). Scotopic flash ERG ratio was 5.0 ± 4.4 for the study and 1.3 ± 0.6 for the control eye (p = 0.012). No differences were observed for the amplitude and latency of flash VEP response after SOR. Conclusions: Silicone oil causes a reduction in flash ERG responses; no effect was found on flash VEP responses. ERGs in eyes filled with silicone oil should not be considered representative of retinal functionality, in contrast to VEPs, which are not affected by silicone oil presence.(AU)

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The hydrophilic and porous structure of cement-based concrete materials makes it vulnerable to various harmful ions dissolved in water in the environment or during the freeze-thaw cycle, resulting in a significant decline in durability. Therefore, the introduction of hydrophobic hydroxyl silicone oil with good chemical stability and excellent hydrophobic properties during the process of concrete preparation to achieve the hydrophobic modification of its internal holes has very positive significance in terms of improving its durability. In order to disperse the hydrophobic hydroxyl silicone oil evenly in the internal pores of the concrete, synthetic non-ionic polyether-modified silicone oil was used as an emulsifier to make it a water-soluble emulsion. The influences of the composition of the emulsifier on the dispersion, water contact angle, water absorption, porosity, and compressive strength of cement mortar were investigated. The results show that when the emulsion content is 0.5%, the pore volume of the cement mortar decreases by 15%, and the maximum contact angle reaches 128°, which is conducive to improving the anti-erosion and anti-freezing properties of concrete and provides a new solution for the preparation of high-durability concrete. However, the introduction of polyether-modified silicone oil increases the number of large holes in the cement mortar, and leads to an increase in water absorption and a decrease in compressive strength. It is necessary to further optimize the composition of emulsifier in future work.

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OBJECTIVE: To study the safety and efficacy of intravitreal infliximab administered at the conclusion of pars plana vitrectomy (PPV) in the treatment of proliferative vitreoretinopathy (PVR) associated with rhegmatogenous retinal detachment (RRD). DESIGN: Randomized controlled phase II clinical trial. SUBJECTS: Patients with primary RRD and grade C PVR, according to the updated Retina Society Classification. METHODS: Sixty-six patients were randomized in a 1:1 ratio to undergo PPV and silicone oil (SO) injection with or without intravitreal injection of 1 mg/0.05 mL of infliximab in the air-filled globe before SO injection at PPV conclusion. Surgeons were masked to treatment allocation until PPV conclusion. MAIN OUTCOME MEASURES: The primary outcome measure was anatomic success (defined as complete retinal reattachment without a tamponade at 6 months post SO removal). Secondary outcome measures were final best-corrected visual acuity (BCVA), single-operation success rate (SOSR), rate of recurrent detachment, central macular thickness (CMT) by macular OCT, macular function by multifocal electroretinogram, and macular vascular density (VD) by OCT angiography. RESULTS: Sixty eyes of 60 patients, 30 eyes in each group, completed the study. At baseline, there were no differences regarding age, gender, history of trauma, lens status, duration of RRD, BCVA, intraocular pressure (IOP), intraocular inflammation (IOI), detachment extent in clock hours, number/size of breaks, presence of vitreous hemorrhage, axial length, or grade/extent of PVR between both groups. For the outcome measures, 30 eyes in the infliximab group achieved anatomic success vs. 29 eyes in the control group. The SOSR was higher in the infliximab group (26) vs. the control (23), but this was not statistically significant (P = 0.317). Final logarithm of the minimum angle of resolution BCVA was better in the infliximab group (mean, 0.96; standard deviation [SD], 0.4; Snellen equivalent ≈ 20/180) vs. the control (mean, 1.14; SD, 0.4); Snellen equivalent ≈ 20/280; P = 0.044). There were no differences regarding IOP, IOI, time of SO removal, macular function, CMT, or VD. CONCLUSIONS: Pars plana vitrectomy with SO tamponade with or without intravitreal infliximab is effective in treating PVR-associated RRD. Infliximab may be associated with modest improvement in final visual outcomes but not anatomic outcomes. FINANCIAL DISCLOSURE(S): The authors have no proprietary or commercial interest in any materials discussed in this article.

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BACKGROUND: The long-term safety and efficacy of repeated applications of subliminal transscleral cyclophotocoagulation (SL-TSCPC) with a focus on cumulative energy was evaluated in glaucoma patients. METHODS: In this retrospective, multicentric study the data of a total of 82 eyes with various causes of glaucoma that were treated with a single or multiple applications of SL-TSCPC were collected. Treatments were performed under general or local anesthesia with an 810 nm diode laser. Power was 2000 mW; duty cycle, 31.3%; total treatment duration, 80-320 s; equaling a total energy of 50-200 J per treatment session. Fifty-five eyes (55 patients) presented for all follow-ups, and these eyes were selected for further statistical analysis. The mean age was 60.0 ± 17.1 years, and 22 (40%) of the patients were female. Intraocular pressure (IOP) and dependence on further glaucoma medication were evaluated at 12 months following the initial treatment. RESULTS: Eyes underwent 1 or 2 consecutive SL-TSCPC treatments. Median (min-max) baseline IOP of 34 (13-69) decreased to 21.5 (7-61), 22 (8-68), 20 (9-68), and 19.5 (3-60) mmHg at the 1, 3, 6, and 12-month postoperative timepoints respectively. The mean (± SD) IOP decrease at 12 months was 26 ± 27%, 39 ± 32%, and 49 ± 33% in the low (below 120 J, n = 18), medium (120-200 J, n = 24), and high (above 200 J, n = 13) cumulative energy groups respectively. At the 12-month timepoint, oral carbonic anhydrase use was discontinued in ¾ of the cases. CONCLUSIONS: It was found that the repeated application of SL-TSCPC safely and efficiently decreases IOP in a Caucasian population with heterogenous causes of glaucoma, eyes with silicone oil responded to a greater extent. Inclusion of cumulative energy scales may contribute to better addressing repeated procedures in a standardized fashion.

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PURPOSE: To clarify the definition, prevalence and classification of different types of unexplained vision loss associated with silicone oil (SO) endotamponades (SO in situ (SOIS) or after removal of SO (ROSO)) in vitreoretinal surgery and identifying the most specific clinical findings and suggesting possible causes. METHODS: Review of the literature regarding randomized clinical trials (RCTs), retrospective case-control, cohort studies and case series evaluating the risk of using SO, published in English between 1994 and 2023, conducting a computer-based search of the following databases: PubMed, Web of Science, Scopus and Embase. The search was supplemented using the Medline option 'Related Articles' and consulting review articles on the topic. RESULTS: Findings from reported clinical examinations in SOIS and ROSO are analyzed and finally different theories regarding the underlying pathophysiology are described. From the clinical point of view, findings have been found in OCT, OCTA, microperimetry and electrophysiological studies. Other clearly identifiable causes of vision loss related to the use of SO are listed and commented as differential diagnosis. Finally, the different physiopathological theories of the two types of causes of unexplained vision have been analyzed. CONCLUSION: Unexpected vision loss under or after SO tamponade (SOIS and ROSO) is a significant concern which is probably underestimated because it is not a clearly defined and known entity. The most frequently described changes were in the ganglion cell complex but this unexpected vision loss remains a serious and unexplained concern for vitreoretinal surgeons and should be identified by clinicians, addressed by manufacturers and reported to Health Authorities as a serious incident according to the new regulation.

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BACKGROUND: The main purpose of this paper is to introduce a method that can accurately locate the posterior capsule of the lens to facilitate a relatively complete resection of the anterior vitreous body. METHODS: A total of 51 patients in the experimental group and control group were enrolled in this study. Phacoemulsification combined with vitrectomy was performed in all cases. After the cataract procedure was completed in the control group, the surgeon performed a conventional anterior vitrectomy with the operative eye. In the experimental group, anterior vitrectomy was performed according to the threadiness corrugation of the posterior capsule of the lens. During the operation, with the help of triamcinolone, two surgeons confirmed the resection of the anterior vitreous cortex; the best corrected visual acuity and intraocular pressure of all patients were recorded at 1 week, 1 month and 3 months after surgery. RESULTS: Fifty patients underwent phacoemulsification combined with vitrectomy, except one patient in the experimental group who was lost to follow-up. After surgery, no significant complications were observed in all patients except two patients in the control group with temporary increases in intraocular pressure. There was no significant difference in preoperative visual acuity between the two groups (t = 0.83, P = 0.25). Both groups had varying degrees of improvement in best corrected visual acuity at 1 week, 1 month and 3 months after surgery. Moreover, there was no significant difference in BCVA between the two groups at the three follow-up time points (t=-1.15, -1.65, -1.09, P = 0.53, 0.21, 0.23). After surgery, no significant complications were observed in all patients except two patients in the control group with temporary increases in intraocular pressure. Incomplete resection of the anterior vitreous cortex was observed in 2 patients in each group, but there was no significant difference (χ2 = 7.81, P > 0.05). CONCLUSION: In the process of cataract surgery combined with vitrectomy, thready corrugation appears in the posterior capsule of the lens and is an important sign of its localization. Anterior vitrectomy can be accomplished safely and effectively with the help of thread-like corrugation, and the surgical effect is almost the same as that of traditional surgery. Especially suitable for beginners in vitreous surgery.

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