Title

AGITATION OF THE SYRINGE AND RELEASE OF SILICONE OIL

Introduction

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 to the syringes without agitation. There was a statistically significant difference between the 3 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.

Discussion

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.

Keywords

intravitreal injection; silicone oil; syringe.

Area

CLINICAL CASE

Authors

Celso de Souza Dias Júnior, Alexandre Lima Cardoso, Ana Galrão de Almeida Figueiredo, Shoko Ota, Gustavo Barreto Melo