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bioRxiv · 10.1101/2024.06.06.597725

The role of eye movements in the process of silicone oil emulsification after vitreoretinal surgery

Nepita, I.·Brusati, C.·Liggieri, L.·Ravera, F.·Ferrara, M.·Stocchino, A.·Romano, M. R.·Santini, E.·Repetto, R.
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Abstract

BackgroundEmulsification of silicone oil (SO) is a feared and common complication of SO tamponade as potentially associated with significant risks to ocular health, including elevated intraocular pressure (IOP), glaucoma, corneal and retinal changes. The aim of this study was to investigate the role and interplay of major factors on the formation of SO emulsion, such as eye rotations and albumin, a blood serum protein known to affect interfacial properties. MethodsExperiments were conducted in a realistic model of the vitreous chamber, filled with SO and an aqueous solution containing different concentrations of albumin. The model was subjected to harmonic and saccadic rotations, at body temperature. ResultsNo emulsions were detected in the absence of endogenous proteins in the aqueous solution. The presence of albumin significantly influenced emulsion formation, acting as a surfactant. Mechanical energy from eye movements was also found to contribute to emulsification, with higher mechanical energy provided to the system leading to smaller droplet sizes. The emulsions formed were stable over extended times. ConclusionsThis study highlights the complex interplay of factors influencing SO emulsification in the vitreous chamber. A better understanding of the mechanisms underlying SO emulsification is crucial for developing strategies to mitigate SO emulsion and the related complications.

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Nepita, I., Brusati, C., Liggieri, L., Ravera, F., Ferrara, M., Stocchino, A., Romano, M. R., Santini, E., Repetto, R.. 2024-06-09. The role of eye movements in the process of silicone oil emulsification after vitreoretinal surgery. https://doi.org/10.1101/2024.06.06.597725

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