LARGE SILICONE DROPLETS AFTER INTRAVITREAL BEVACIZUMAB (AVASTIN)

[Translated article] Syringes for intraocular administration: A systematic review

OBJECTIVE

The off-label use in clinical practice of non-approved syringes for intravitreal drug administration has resulted in the detection of silicone oil drops in the vitreous of some patients. This situation derives from the lack of approved syringes for intraocular use in the Spanish market. The aim of this work is to review the use of syringes for intraocular administration, as well as to search for alternatives that meet the legal requirements for these unmet needs.

METHOD

A systematic review was performed following the PRISMA 2020 guidelines by searching PubMed with the descriptors: (silicone) AND (syringes) AND ((intraocular) OR (intravitreal)) and filtering all existing publications from January 2006 to December 2023, including all those articles dealing with silicone oil release in intravitreal injections and analysing the possible consequences.

RESULTS

Sixty-eight results were found, 23 of which were excluded because they did not deal with the subject under study, leaving a total of 45 articles for the systematic review. These were classified according to the conclusions obtained in 4 groups: the adverse reactions produced by silicone; the administration technique; the physicochemical aspects of silicone release; and the characteristics of the medical device. After reviewing the current manufacturers and technical data sheets of commercialised syringes, the existing syringes for this use have been collected, finding 2 that will probably be commercialised in Spain at the beginning of 2024: Zero Residual™ 0.2 ml SiO-free and VitreJect® Ophthalmic.

CONCLUSIONS

From the results obtained, it can be interpreted that the use of syringes and needles with silicone for intravitreal use is a concern for health professionals due to the implications and consequences that may arise in patients, the most important being adverse reactions, so it is necessary to have silicone-free syringes on the market that are specific for intraocular use. Safety and legality in the use of intraocular syringes and needles is essential to guarantee ocular integrity and patient health.

Syringes for intraocular administration: Systematic review

OBJECTIVE

The off-label use in clinical practice of non-approved syringes for intravitreal drug administration has resulted in the detection of silicone oil drops in the vitreous of some patients. This situation derives from the lack of approved syringes for intraocular use in the Spanish market. The aim of this work is to review the use of syringes for intraocular administration, as well as to search for alternatives that meet the legal requirements for these unmet needs.

METHOD

A systematic review was performed following the PRISMA 2020 Guidelines by searching PubMed with the descriptors: "silicone" AND "syringes" AND ("intraocular" OR "intravitreal") and filtering all existing publications from January 2006 to December 2023, including all those articles dealing with silicone oil release in intravitreal injections and analysing the possible consequences.

RESULTS

Sixty-eight results were found, 23 of which were excluded because they did not deal with the subject under study, leaving a total of 45 articles for the systematic review. These were classified according to the conclusions obtained in 4 groups: the adverse reactions produced by silicone, the administration technique, the physicochemical aspects of silicone release, and the characteristics of the medical device. After reviewing the current manufacturers and technical data sheets of commercialized syringes, the existing syringes for this use have been collected, finding two that will probably be commercialized in Spain at the beginning of 2024: Zero Residual™ 0.2 ml SiO-free and VitreJect® Ophthalmic.

CONCLUSIONS

From the results obtained, it can be interpreted that the use of syringes and needles with silicone for intravitreal use is a concern for health professionals due to the implications and consequences that may arise in patients, the most important being adverse reactions, so it is necessary to have silicone-free syringes on the market that are specific for intraocular use. Safety and legality in the use of intraocular syringes and needles is essential to guarantee ocular integrity and patient health.

Evidence-Based Use of Bevacizumab in the Management of Neovascular Age-Related Macular Degeneration

Indicated for colorectal cancer for decades, bevacizumab has been widely used off label to treat retinal diseases, and the benefits of its use, specifically in neovascular age-related macular degeneration, have been demonstrated in multiple clinical trials. The intravitreal delivery of bevacizumab requires it to be aseptically repackaged into individual syringes by compounding pharmacies for use in the eye. Although the repackaging process is permitted by the US Food and Drug Administration, the resultant product does not meet the specific standards of products approved for use as ophthalmic injectables nor is the parenteral innovator solution compliant with ophthalmic standards. Studies have also demonstrated variability in the quality and quantity of repackaged bevacizumab. This narrative review summarizes the evidence and discusses the role of off-label bevacizumab in the treatment and management of retinal diseases, its mechanism of action, current challenges and provides a critical appraisal of current evidence, clinical implications, and future directions. [Ophthalmic Surg Lasers Imaging Retina 2024;55:155-162.].

Application of Formulation Principles to Stability Issues Encountered During Processing, Manufacturing, and Storage of Drug Substance and Drug Product Protein Therapeutics

The field of formulation and stabilization of protein therapeutics has become rather extensive. However, most of the focus has been on stabilization of the final drug product. Yet, proteins experience stress and degradation through the manufacturing process, starting with fermentaition. This review describes how formulation principles can be applied to stabilize biopharmaceutical proteins during bioprocessing and manufacturing, considering each unit operation involved in prepration of the drug substance. In addition, the impact of the container on stabilty is discussed as well.

Presumed Silicone Oil Droplets After Intravitreal Pegcetacoplan Injections

Importance

Recently, intravitreal pegcetacoplan became the first drug to gain US Food and Drug Administration approval for the treatment of geographic atrophy associated with nonexudative age-related macular degeneration, but the administration of this medication may be associated with unanticipated posttreatment complications.

Objective

To assess the prevalence of presumed silicone oil droplets in the vitreous cavity after intravitreal injection of pegcetacoplan.

Design, Setting, and Participants

This case series study involved a retrospective record review of all 55 patients treated with intravitreal pegcetacoplan, 0.1 mL in 150-mg/mL solution, between March 24 and June 5, 2023, at a single specialty retina practice. All injections were done using needles from the kit supplied by Apellis Pharmaceuticals on a 1-mL McKesson Luer lock syringe.

Main Outcomes and Measures

The presence or absence of presumed silicone bubbles detected during dilated biomicroscopic fundus examination and/or on color fundus photographs, the presence or absence of symptoms, change in visual acuity, and/or increase in intraocular pressure.

Results

A total of 62 intravitreal pegcetacoplan injections were given to 55 patients (mean [SD] age, 83.8 [7.8] years; 33 women [60%]) from March 24 to June 5, 2023. Of the 55 patients, 16 (29%; mean [SD] age, 83.8 [7.4] years; 9 women [56%]) had presumed intravitreal silicone droplets discovered 2 to 4 weeks after treatment, 3 of which were documented on color fundus photographs. Of the 16 patients, 14 (88%) were symptomatic for new floaters that they described as persistent, while 2 (13%) were asymptomatic. There were no signs of inflammation or infection, no increases in intraocular pressure, and no changes in visual acuity for all 16 patients.

Conclusions and Relevance

A substantial percentage of patients had symptomatic floaters from presumed intravitreal silicone oil droplets after injections of pegcetacoplan using a McKesson 1-mL Luer lock syringe. These findings support consideration of informing patients of this potential adverse effect, avoiding use of the McKesson syringe, and considering use of silicone-free syringes for pegcetacoplan injections.

Silicone Oil Droplet Over the Optic Nerve Head After Intravitreal Injections

This case report discusses the finding of a silicone oil droplet over the optic nerve head of a patient with a history of multiple intravitreal injections.

Ocular inflammation after agitation of siliconized and silicone oil-free syringes: a randomized, double-blind, controlled clinical trial

Background

Noninfectious endophthalmitis may be misdiagnosed, leading to serious clinical implications. So far, its causative factors remain unknown. Therefore, this study assessed the role of silicone oil and syringe agitation in the development of inflammation after intravitreal injection of aflibercept.

Methods

A randomized, double-blind, controlled clinical trial included subjects with an indication of intravitreal antiangiogenic therapy prior to vitrectomy for proliferative diabetic retinopathy. Aflibercept was injected 48 h before surgery. The control group received the injection without agitation, while the intervention group was injected with a previously agitated syringe by flicking with either a siliconized or silicone oil-free syringe. The primary endpoint was the presence of anterior chamber reaction (ACR) at 48 h. Aqueous samples were collected and underwent cytometric bead array analysis for quantification of interleukins and chemokines.

Results

Forty-one individuals were included (21 in the agitation group and 20 in the no-agitation group). None of the included eyes showed baseline signs of AC cells, hyperemia or pain complaint, while 10% of control group and 80% of agitation group showed AC cells 48 h after injection of aflibercept with SR syringe. There were no differences in the mean variations of all cytokines and chemokines by agitation status. However, there was a marginally significant increase between the mean variations of IP-10 (p = 0.057) and IL-8 (p = 0.058) in the siliconized one.

Conclusion

This clinical trial discloses a potential role of agitation and siliconized syringes in the development of inflammation after an intravitreal injection of aflibercept. These findings have important clinical implications for all healthcare practitioners who perform intravitreal injections.

Trial Registration: Brazilian Registry of Clinical Trials, RBR-95ddhp. Registered 12 May 2019, http://www.ensaiosclinicos.gov.br/rg/RBR-95ddhp/

Frequency and Symptoms of Intravitreal Silicone Oil Droplets Following Becton Dickinson and Norm-Ject Bevacizumab Injections

BACKGROUND AND OBJECTIVE

To determine silicone oil droplet frequency and symptomatic impact in patients injected with Norm-Ject (NJ) and/or Becton Dickinson (BD) intravitreal bevacizumab.

PATIENTS AND METHODS

This was a retrospective cohort study of 426 patients with prior bevacizumab injection(s). Symptomatic floaters questionnaire responses were compiled and statistical analysis was performed using Fisher's exact t test with 95% CI calculated via the modified Wald method.

RESULTS

Patients who received BD intravitreal bevacizumab showed more droplets (67.2%) than those who received NJ intravitreal bevacizumab (7.8%), and droplets increased with injection quantity. However, the symptomatic patients reporting new floaters were similar (NJ: 39.22%, BD: 39.47%). [Ophthalmic Surg Lasers Imaging Retina. 2022;53:108-112.].

Silicone oil-free syringes, siliconized syringes and needles: quantitative assessment of silicone oil release with drugs used for intravitreal injection

PURPOSE

This study aimed to quantify the amount of silicone oil (SO) released across a variety of syringe and needle models routinely used for intravitreal injection.

METHODS

The release of SO was assessed in eight models of syringes, two of which were reported to be 'SO-free', and eleven models of needles with unknown SO content. To evaluate SO release within the context of anti-VEGF therapeutics, syringes were evaluated using aflibercept, bevacizumab, buffer, ziv-aflibercept and formulation buffer. All syringe tests were performed with or without agitation by flicking for syringes. Needles were evaluated without agitation only. Samples were fluorescently labelled to identify SO, and triplicate measurements were collected using imaging flow cytometry.

RESULTS

Seven out of 8 syringe models showed a statistically significant increase in the SO particle count after agitation. The two SO-free syringe models (HSW Norm-Ject, Daikyo Crystal Zenith) released the least SO particles, with or without agitation, whereas the BD Ultra-Fine and Saldanha-Rodrigues syringes released the most. More SO was released when the syringes were prefilled with formulation buffer than with ziv-aflibercept. Syringes filled with aflibercept and bevacizumab had intermediate levels. Agitation increased the release of SO into each of the drug solutions. Silicone oil (SO) was detected in all needles.

CONCLUSIONS

Agitation of the syringe by flicking leads to a substantial increase in the number of SO particles. Silicone oil (SO)-free syringes had the best performance, but physicians must also be aware that needles are siliconized and also contribute to the injection of SO into the vitreous.

Silicone microbubbles after anti-vascular endothelial growth factor injections in patients with wet age-related macular degeneration: incidence, quantification and secondary optical coherence tomography artfacts

PURPOSE

To report the incidence and quantity of silicone oil microbubbles and the relationship with the number of intravitreal anti-vascular endothelial growth factor (VEGF) injections and evaluate if microbubbles induce artefacts on optical coherence tomography (OCT) images.

METHODS

Observational, descriptive, cross-sectional study. Patients with wet age-related macular degeneration were included who had been treated for 1 year minimally with anti-VEGF injections repackaged in the hospital pharmacy. Detection and quantification of silicone microbubbles by mydriatic biomicroscopic examination were conducted 1 month after the last injection. The numbers of microbubbles were quantified on a scale of 0-3: 0, none; 1 scarce (1-10 microbubbles); 2 moderate (10-30); or 3 numerous (>30). Shadowing on OCT images was classified as 0-3: 0, none; 1 obscuring some retinal layers; 2 obscuring all retinal layers; or 3 obscuring the retinal thickness.

RESULTS

The study included 142 eyes of 98 patients (mean age, 82.4 years + 7.3; range, 65-97) treated with 2377 injections. Microbubbles were detected in 127 (89.4%) eyes, 62 (43.6%) with numerous microbubbles and 36 (25.4%) and 29 (20.4%), respectively, with scarce and moderate numbers. A positive correlation was found between the numbers of injections and intravitreal silicone (rho, 0.7). Optical coherence tomography (OCT) artefacts were detected in 11 eyes; the artefacts obscured all retinal layers in three eyes. No significant relationship could be established between the appearance of floaters and the microbubbles.

CONCLUSION

The presence and number of silicone microbubbles were correlated with the number of intravitreal injections. Microbubbles can produce OCT artefacts, which can hinder the treatment decision.

Intravitreal Injection Therapy: Current Techniques and Supplemental Services

Purpose:

Intravitreal injection is the most frequently performed eye procedure in the world and is an essential component in the management of sight-threating retinal diseases and conditions. Given the seriousness and range of diseases treated and the risks of the procedure, retina specialists must weigh the pros and cons of each individual treatment. Complexities guiding injection treatment are multifaceted and involve patient-history review, careful examination, diagnostic testing selection and interpretation, customized medical decision-making, and follow-up considerations.

Methods:

This article by the Intravitreal Injection Task Force Committee of the American Society of Retina Specialists documents the intricacies and necessary components of the intravitreal injection procedure.

Results:

By expert consensus, the task force further recommends ancillary services and decision-making that may accompany intravitreal injection visits, when appropriate, to monitor response to treatment, adjust treatment, and manage additional considerations in the same or fellow eye.

Conclusions:

Retina specialists can optimize safety and therapeutic outcomes with individualized consideration and customization of intravitreal injection treatment for each patient.

In-vitro assessment of release of silicone oil droplets with the use of variety of syringes and needles used in intravitreal injections

PURPOSE

To assess the variability of silicone oil (SO) particles released across syringes from the same lot and the role of different needle gauges.

MATERIALS AND METHODS

Four syringe models and six needle models were assessed for SO release. About 50 microliters of a buffer solution were loaded into the syringe, needle or syringe/needle setup. The data were analyzed by imaging flow cytometry with fluorescently labeling for SO.

RESULTS

All syringe models had a high coefficient of variation in SO release across syringes from the same lot. The amount of SO was significantly greater in the syringe when the needle was attached. SO particles with the BD 30G needle attached to the syringe were statistically greater than the 27G counterpart (p = 0.005). None of the other comparisons was statistically different. Finally, the number of SO particles was higher in the syringe/needle setup than in needles only (p = 0.0024).

CONCLUSION

We found a high variability in SO content across syringes from the same lot. Additionally, there was no clear association between needle gauge and the number of SO particles, as well as their coefficient of variation. Finally, the needles accounted for a small number of SO particles in comparison to the combined syringe-needle setup.

Drug-related adverse effects of antivascular endothelial growth factor agents

PURPOSE OF REVIEW

Antivascular endothelial growth factor (VEGF) agents have provided historic therapeutic breakthroughs in the treatment of retinal disease. New anti-VEGF agents are emerging for the treatment of retinal vascular diseases. Both systemic and ocular adverse effect need to be understood in managing patients. This review aims to highlight the adverse effects seen with routine use of bevacizumab, ranibizumab and aflibercept, as well as with new medications such as brolucizumab and abicipar.

RECENT FINDINGS

We review the recent findings of intraocular inflammation (IOI) of brolucizumab and abicipar in the context of the efficacy and safety reported with the routine anti-VEGF agents. Specifically, brolucizumab has been reported to cause occlusive retinal vasculitis in the setting of IOI, which has not been seen in other anti-VEGF medications. In addition, abicipar appears to cause IOI at a higher rate of patients than other anti-VEGF agents have previously.

SUMMARY

Newer anti-VEGF agents pose a significant risk of adverse events not seen with routine anti-VEGF agents.

Observation of Silicone Oil Within the Vitreous and Sclera Following Intravitreal Administration of Biotherapeutics Using Insulin Syringes in Cynomolgus Monkeys

Silicone oil droplets have been reported in the eyes of human patients following intravitreous (IVT) injections with several marketed biotherapeutic products. Intravitreous administration of a novel biotherapeutic in a 14-week cynomolgus monkey study using insulin syringes was associated with 2, non-test-article-related phenomena: "vitreous floater/clear sphere" on indirect ophthalmoscopy and intrascleral "foreign material near injection track" on histopathology. Retrospective analysis of 81 other preclinical studies of IVT administration of novel biotherapeutics found a greater frequency of clear spheres in monkey IVT studies using insulin syringes and formulations containing polysorbate. We were able to correlate microscopic findings of clear circular to oval areas in the sclera near the injection track with an energy-dispersive X-ray spectroscopy (EDS) signal for silicon at the same location in the sclera. These observations provide further evidence that silicone lubricant in insulin syringes/needles is the source of clear spheres noted in the vitreous and foreign material noted near the injection track in the sclera. Although considered inert and toxicologically insignificant, silicone deposition within the eye should form part of the risk-benefit equation in a clinical setting.

RETAINED, NONDISSOLVING, TUBULAR FOREIGN BODIES IN THE VITREOUS CAVITY AFTER INTRAVITREAL DEXAMETHASONE (OZURDEX) IMPLANTATION

PURPOSE

To describe the retention of large, tubular, nondissolving foreign bodies because of a complication of the intravitreal dexamethasone implant (Ozurdex).

METHODS

This is a single-center, retrospective chart review of patients who were found to have retained, nondissolvable tubular foreign bodies in the vitreous cavity for more than 6 months (the expected dissolution time of the implants) after Ozurdex injections. Ocular symptomatology and multimodal imaging were reviewed.

RESULTS

Five patients had retained, nondissolvable tubular foreign bodies in the vitreous that persisted for months (mean 28.2 months, range 9-67 months) after intravitreal injection of Ozurdex. Two patients were symptomatic due to the foreign bodies and chose alternate local therapy, but none of the patients opted for surgical explantation.

CONCLUSION

Persistent, nondissolving, tubular foreign bodies can be seen in the vitreous cavity for years after injection of the Ozurdex implant. Clinicians should be aware of this complication that has the potential to cause visual symptoms and ocular morbidity.

Critical analysis of techniques and materials used in devices, syringes, and needles used for intravitreal injections

Intravitreal injections have become the most commonly performed intraocular treatments worldwide. Because intravitreal injections may induce severe adverse events, such as infectious and noninfectious endophthalmitis, cataract, ocular hypertension, vitreous hemorrhage, or retinal detachment, appropriate awareness of the materials and techniques used are essential to reduce these sight-threatening complications. This review provides insights into the needles, syringes, silicone oil coating, sterilization methods, devices to assist intravitreal injections, scleral piercing techniques using needles, syringe handling, anesthesia, and safety issues related to materials and techniques. It is paramount that physicians be aware of every step involved in intravitreal injections and consider the roles and implications of all materials and techniques used. The ability to understand the theoretical and practical circumstances may definitely lead to state-of-the-art treatments delivered to patients. The most important practical recommendations are: choosing syringes with as little silicone oil as possible, or, preferably, none; avoiding agitation of syringes; awareness that most biologics (e.g., antiangiogenic proteins) are susceptible to changes in molecular properties under some conditions, such as agitation and temperature variation; understanding that improper materials and techniques may lead to complications after intravitreal injections, e.g., inflammation; and recognizing that some devices may contribute to an enhanced, safer, and faster intravitreal injection technique.

Agitation of the syringe and release of silicone oil

BACKGROUND/OBJECTIVES

To investigate whether agitation promotes the release of silicone oil by different models of syringe used for intravitreal injection.

METHODS

This lab study analyzed eight syringe models by light microscopy for the release of silicone oil under agitation (flick), without agitation, and positive controls. Fourier-Transform Infrared Spectroscopy (FTIR) was performed to identify the molecular compounds inside the syringes.

RESULTS

A total of 240 syringes were analyzed. The presence of silicone oil droplets was observed in all positive controls. When agitated by flicking, 100% of the samples of the syringes disclosed silicone oil, except the BD Plastipak syringe, which presented 40% of positivity. Without agitation, a smaller percentage of samples with silicone oil was observed. Agitation by flicking had a 265-fold greater chance of presenting oil droplets when compared with the syringes without agitation. There was a statistically significant difference between the three conditions (P < 0.05). Analysis of the tip of the plunger rubber by FTIR indicated the presence of polysiloxane (silicone oil) in all models of syringe.

CONCLUSIONS

Agitation of the syringe promotes the release of silicone oil. It is recommended to improve the technique of injection and the manufacture of specific syringes for ophthalmological use.

A new method for pharmaceutical compounding and storage of anti-VEGF biologics for intravitreal use in silicone oil-free prefilled plastic syringes

Intravitreal injections of antibody-based biologics targeting vascular endothelial growth factor (VEGF) are highly effective and have markedly decreased the risk of visual impairment associated with prevalent retinal diseases, such as neovascular age-related macular degeneration and diabetes macular oedema. The diseases are chronic in their nature, and most patients need long-term therapy to suppress disease activity. We previously reported a compounding method for repackaging and storage of aflibercept (Eylea), a commonly used anti-VEGF biologic, in silicone oil-coated plastic syringes without compromising drug stability or activity. In addition to improving safety and time spent per patient, compounding of anti-VEGF biologics enables single-dose vials to be split into multiple syringes, thereby considerably reducing waste and drug expenses. However, symptomatic silicone oil droplets may deposit in the eye’s vitreous body after repetitive injections. To fully avoid this complication, we here report on a novel pharmaceutical compounding method using silicone oil-free syringes and a 33 G × 9 mm Low Dead Space Needle hub injection needle. We evaluate the method for three anti-VEGF biologics commonly used in ophthalmology: aflibercept, ranibizumab (Lucentis) and bevacizumab (Avastin). Our results show that compounding and storage for one week does not compromise the functional activity of the biologics and allows for safe and cost-effective compounding of anti-VEGF biologics for intravitreal injections in prefilled silicone oil-free syringes.

Prevalence of silicone oil droplets in eyes treated with intravitreal injection

Objective

To assess the number of eyes with silicone oil in the vitreous after intravitreal injection.

Methods

This cross-sectional, comparative study was divided into 2 groups: (1) treatment—eyes subjected to antiangiogenic therapy; (2) control—no history of intravitreal injection. Subjects were assessed regarding age, gender, clinical diagnosis, lens status, visual acuity and number of previous intravitreal injections. All eyes underwent a meticulous slit-lamp and ultrasound examination for the identification of silicone oil. ImageJ software was used to quantify the index of silicone oil (IOS) by ultrasonography.

Results

Sixty-seven eyes (30 controls, 37 treated) were included. Slit-lamp examination found silicone oil droplets in 25 out of 37 (67.57%) treated eyes and in none of the control group. Ultrasonography identified silicone oil in 28 out of 37 (75.68%) treated eyes and in 1 out of 30 (3.33%) controls. An observed agreement of 85.07% and a Cohen’s Kappa coefficient of 69.10% (p < 0.0001) between ultrasonography and biomicroscopy were found. Wilcoxon test showed a statistically significant difference (p = 0.0006) in IOS between controls (0.41 ± 0.43%) and treated eyes (2.69 ± 2.55%). Spearman’s correlation test (0.61; p < 0.0001) showed that the greater the number of injections, the higher the IOS.

Conclusions

Silicone oil droplets were found in the majority of the eyes previously treated with antiangiogenic intravitreal injection. The greater the number of injections, the higher the likelihood of finding silicone oil. An improvement in the technique of injection and better-quality syringes post-injection silicone oil droplets.

Release of silicone oil and the off-label use of syringes in ophthalmology

BACKGROUND/AIMS

To assess silicone oil (SO) release by different brands of syringes used for intravitreal injection under different handling conditions.

METHODS

Eight syringes were analysed: from the USA, Terumo 0.5 mL, Becton-Dickinson (BD) Tuberculin 1 mL, BD Luer-lok 1 mL, BD Ultra-Fine 0.3 mL and Exel Insulin 0.3 mL; from Germany, Braun Omnifix-F 1 mL and Braun Injekt-F 1 mL and from Spain, BD Plastipak 1 mL. The impact of air, priming the plunger, agitation by flicking and fluid temperature on SO release were assessed by light microscopy. Fourier transform infrared spectroscopy (FTIR) was performed to identify the molecular compound in each syringe.

RESULTS

Five hundred and sixty syringes were analysed. Terumo 0.5 mL and BD Ultra-Fine 0.3 mL released more SO than all others. BD Luer-lok 1 mL, BD Plastipak and Braun Omnifix-F 1 mL released little SO; BD Tuberculin 1 mL, Exel 0.3 mL and Braun Injekt-F 1 mL released the least SO. Priming the syringe and different temperatures did not significantly affect SO release. Agitation by flicking caused a significantly higher proportion of samples to have SO droplets and an increased number of oil droplets. Air had an additive effect on the release of oil in the agitation groups. FTIR identified polysiloxane in all syringes but Injekt-F.

CONCLUSION

Syringes commonly used for intravitreal injections frequently release SO droplets, especially when agitated by flicking. To avoid unnecessary ocular risks, syringes should not be agitated before intravitreal injection. It is desirable that syringes be manufactured specifically for ophthalmic use.

Silicone oil droplets in repackaged anti–vascular endothelial growth factors for intravitreal injections: In search of the main source of contamination

Introduction:

Repackaging of anti–vascular endothelial growth factors in polypropylene syringes lubricated with silicone oil for intravitreal use is associated with the presence of intravitreal silicone oil droplets. The objective of this study is to assess how the use of silicone-free syringes (for storage and/or administration) would reduce the amount of silicone oil droplets in the product to be administered.

Methods:

Two 16 mL vials of bevacizumab were repackaged at the compounding pharmacy to obtain four sets of product, each consisting of three 1.2 mL tubes of the drug repackaged in different ways. Set A was repackaged according to routine practice, that is, the drug was placed into 1 mL siliconized syringes and 60 µL aliquots were extracted with 0.5 mL insulin siliconized syringes until reaching 1.2 mL. In set B, a 1-mL silicone-free syringe was used, followed by a 0.5 mL siliconized syringe. In set C, only 0.5 mL siliconized syringes were used. In set D, only the 1-mL silicone-free syringe was used. Micro-Flow Imaging technology was used for quantifying silicone oil droplet–like particles below 25 µm.

Results:

Silicone oil droplet–like particles were absent in set D. Set C had the highest average frequency of these particles, which was much lower in sets A and B. Set B had the lowest frequency.

Conclusion:

0.5 mL insulin syringes with staked-in needles used for supplying the product seem to be the main source of silicone oil contamination in repackaged anti–vascular endothelial growth factors. Silicone-free insulin syringes with staked-in needles would be strongly recommended for supplying anti–vascular endothelial growth factor intravitreal injections from compounding pharmacies.

Release of silicone oil droplets from syringes

BACKGROUND

Intravitreal silicone oil droplets have been found in the vitreous. The aim of this study is to compare the rates of silicone oil released by different brands of commonly used syringes for intravitreal injection after agitation by flicking.

METHODS

Three models of two brands of syringes were analyzed for their rates of silicone oil release: Saldanha Rodrigues (SR) 1 mL insulin syringe (SR, Brazil, syringe 1), Becton-Dickinson (BD) Plastipak 1 mL insulin syringe (Brazil, syringe 2), and BD Safety-Glide 1 mL insulin syringe (USA, syringe 3). All syringes were tested under four different conditions: positive control (fluid with addition of silicone oil) without agitation (group 1, n = 5); positive control with agitation (group 2, n = 3); fluid only without agitation (group 3, n = 5); and fluid only with agitation (group 4, n = 5). Masked graders performed all analyses using light microscopy.

RESULTS

All syringes (1, 2, and 3) released silicone oil droplets in the positive control group regardless of the agitation status (groups 1 and 2). When no oil was added and the syringes were not agitated, only syringe 1 released silicone oil droplets (40% of samples). After agitation, syringes 1 and 3 released silicone oil droplets in all samples. Quantitative analysis showed a significantly (P = 0.011; 11.2 ± 2.9 vs. 0.6 ± 0.9, respectively) higher mean number of silicone oil droplets released by syringe 1 after agitation compared to no agitation. Syringe 1 also had significantly (P = 0.002, 11.2 ± 2.9 vs. 0.0 ± 0.0 vs. 2.2 ± 0.8, respectively) more droplets than syringes 2 and 3 after agitation.

CONCLUSIONS

Syringes commonly used for intravitreal injections frequently release silicone oil droplets when agitated by flicking, especially the SR insulin ones. We recommend that they not be agitated at the time of intravitreal injection and that the manufacturers consider producing syringes adapted for intraocular use.

Complications of Intravitreous Injections in Patients with Diabetes

Intravitreous injections are presently the second most frequently performed ophthalmic procedure and the most common vitreoretinal procedure. In diabetic patients, intravitreous injections are frequently performed for the treatment of center-involved diabetic macular edema, proliferative diabetic retinopathy, or other co-existing retinal vascular disease. Diabetic patients may be at higher risk of adverse events compared to non-diabetic individuals, given frequent systemic comorbidities, such as cardiovascular and renal disease and increased susceptibility to infection. This review highlights the potential complications and safety considerations in intravitreous injections in patients with diabetes.