Abstract
Purpose :
To investigate whether agitation promotes the release of silicone oil by different models of syringe used for intravitreal injection and identify the molecular compounds present inside these syringes
Methods :
This lab study analyzed eight syringe models by light microscopy for the release of silicone oil under agitation (flicks, that is usually performed to dislodge and expel air bubbles prior to the injection), 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 syringes plus two other compounds in smaller amounts: ester carbonyl (Descarpack and BD Plastipak syringes) and carboxylic acid salt carbonyl (SR insulin, both fixed and attachable needle syringes and BD Plastipak 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 (especially silicone oil free)
This is a 2020 ARVO Annual Meeting abstract.