Release of silicone oil droplets from syringes

Abstract

BackgroundIntravitreal 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.MethodsThree 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.ResultsAll 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.ConclusionsSyringes 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.

Prevalence of silicone oil droplets in eyes treated with intravitreal injection

“…In fact, although it is not possible to state which syringe was used for each patient, the syringe models available in the last 5 years at the clinical setting where these patients were treated were Becton–Dickinson (BD) Plastipak 1 mL (Becton, Dickinson [BD] and Co., Curitiba, Brazil), SR 1 mL and BD SafetyGlide 1 mL (BD and Co., Holdrege, NE). Both the SR and the BD SafetyGlide syringes have been shown to release silicone oil droplets, especially after agitation [16]. Coincidently, the retina specialist responsible for those injections in this study used to flick the syringe until a few months prior to the data collection, which we believe promotes a greater detachment of oil from the inner surface of the syringes.…”

“…A case–control analysis reinforced the suspicion that a new syringe introduced at the injection facility had an association with the cases with inflammation [14]. Thereafter, our group carried out experimental studies that showed that silicone oil might be released by syringes under steady-state conditions, but more commonly with agitation by flicking [16–18]. Additionally, needles have been shown to be coated with silicone oil [19].…”

Quantitative Differentiation of Protein Aggregates From Other Subvisible Particles in Viscous Mixtures Through Holographic Characterization

“…The syringes used for this study (Beckton-Dickinson, BD Safety-Glide™ 1 mL insulin syringe with BD Ultra-Fine™ needle) are lubricated with silicone oil and are known to release oil droplets. 36 …”

<p>Issues with Intravitreal Administration of Anti-VEGF Drugs</p>

“…49 Several studies have shown that flicking or agitation of the syringes results in a high amount of silicone oil droplets inside the syringes. 37,50 The authors carried out further investigations on the particle count in two bevacizumab syringes filled by different compounding pharmacies (University and External), as well as the aflibercept vial and the ranibizumab ready-to -use syringe available in Germany. The transport route was also taken into account.…”