Maximilian Hammer 
Heidelberg, 6.2.2022 We proudly want to share with you that the well-respected journal RETINA – has recently published our report on a new kind of cannula made of polyimide that improves the injectability of silicone oil, the commonly used endotamponade.
The background
High-viscosity silicone oils can be hard to inject using small-gauge cannulas in modern day vitreoretinal surgery. We evaluated the possible benefits of a new cannula made of polyimide over regular cannulas made of metal. The new material, polyimide, allows cannulas to have a thinner wall and that increases the inner diameter of the cannula, which the most important aspect in determining the injection speed.
What we did
In this laboratory study, we compared both types of cannulas in use with a variety of commercially available silicone oils, and a novel super high-viscosity silicone oil. Additionally, the cannulas were tested in a feasibility study in porcine cadaver eyes.
What we found
The polyimide cannula decreased the injection time to a quarter for all silicone oils we tested. While conventional metal cannulas failed to inject the super high-viscosity silicone oil, the polyimide-cannula injected a clinically relevant volume in only 10 minutes. We came across no problems when we used the cannulas in vitrectomized porcine cadaver eyes.
In Summary
Hand in hand with the trend towards small incision surgery, is a desire to achieve a longer-acting intraocular effect with silicone oil. Polyimide-cannulas and the polyimide material itself represent a promising step towards bringing together these goals of introducing sustained long-acting endotamponade and small-incision surgery.
To read our paper
How to cite our paper
Hammer, Maximilian cand. med1; Schickhardt, Sonja K PhD1; Munro, Donald1; Khoramnia, Ramin MD1; Scheuerle, Alexander MD1; Mayer, Christian S MD1; Auffarth, Gerd U MD, PhD1 The novel use of high-flow polyimide cannulas to improve silicone oil injectability in vitreoretinal surgery, Retina: February 07, 2022 - Volume - Issue - doi: 10.1097/IAE.0000000000003432
Pupil dynamics